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1.
Int J Mol Sci ; 25(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38791534

RESUMO

C-type lectins play a crucial role as pathogen-recognition receptors for the dengue virus, which is responsible for causing both dengue fever (DF) and dengue hemorrhagic fever (DHF). DHF is a serious illness caused by the dengue virus, which exists in four different serotypes: DEN-1, DEN-2, DEN-3, and DEN-4. We conducted a genetic association study, during a significant DEN-2 outbreak in southern Taiwan, to explore how variations in the neck-region length of L-SIGN (also known as CD209L, CD299, or CLEC4M) impact the severity of dengue infection. PCR genotyping was utilized to identify polymorphisms in variable-number tandem repeats. We constructed L-SIGN variants containing either 7- or 9-tandem repeats and transfected these constructs into K562 and U937 cells, and cytokine and chemokine levels were evaluated using enzyme-linked immunosorbent assays (ELISAs) following DEN-2 virus infection. The L-SIGN allele 9 was observed to correlate with a heightened risk of developing DHF. Subsequent results revealed that the 9-tandem repeat was linked to elevated viral load alongside predominant T-helper 2 (Th2) cell responses (IL-4 and IL-10) in K562 and U937 cells. Transfecting K562 cells in vitro with L-SIGN variants containing 7- and 9-tandem repeats confirmed that the 9-tandem repeat transfectants facilitated a higher dengue viral load accompanied by increased cytokine production (MCP-1, IL-6, and IL-8). Considering the higher prevalence of DHF and an increased frequency of the L-SIGN neck's 9-tandem repeat in the Taiwanese population, individuals with the 9-tandem repeat may necessitate more stringent protection against mosquito bites during dengue outbreaks in Taiwan.


Assuntos
Vírus da Dengue , Lectinas Tipo C , Receptores de Superfície Celular , Dengue Grave , Replicação Viral , Humanos , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Dengue Grave/imunologia , Dengue Grave/virologia , Dengue Grave/genética , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Replicação Viral/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Masculino , Células K562 , Feminino , Células U937 , Taiwan/epidemiologia , Repetições Minissatélites/genética , Adulto , Citocinas/metabolismo , Citocinas/genética , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Pessoa de Meia-Idade , Carga Viral
2.
Int J Mol Sci ; 24(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36768349

RESUMO

Ovarian cancer has the highest mortality rate among gynecological cancers, often diagnosed at the late stage and lacking an effective targeted therapy. Although the study of malignant features of cancer, considered to be cancer stem cells (CSCs), is emerging, the aim of this study was to predict and explore the possible mechanism and clinical value of genetic markers in the development of ovarian cancer from a combined database with CSCs features. The common differentially expressed genes (DEGs) were selected in GSE185833 and GSE176246 datasets from the Gene Expression Omnibus (GEO). The GSE185833 dataset was created to reveal gene expression profiles of peritoneal metastasis tissues using single-cell sequencing, and the GSE176246 dataset was determined from gene expression profiles of chemotherapy-refractory ovarian cancer cell lines compared with ovarian cancer cell lines by RNA-seq analysis. By analyzing the correlation between common DEGs and prognosis of ovarian cancer and its possible pathways and functions were predicted by The Cancer Genome Atlas (TCGA) database. The expression levels of 11 genetic markers were significantly elevated in highly invasive and chemoresistant ovarian cancer. The expression of Actin-like protein 6A (ACTL6A) was found to be correlated with survival prognosis, and the total survival time of the patients with high expression of ACTL6A was shorter than those with low expression. Gene set enrichment analysis (GSEA) showed that ACTL6A positively enriched the gene set of 'Cell cycle' and ACTL6A negatively enriched the gene set of focal adhesion. CP724714, a human epidermal growth factor receptor 2 (HER2) inhibitor, could serve as a therapeutic option when ACTL6A levels are high in ovarian cancer cells. The high expression of ACTL6A is a poor prognostic factor in ovarian cancer and may serve as an effective biomarker for predicting treatment-refractory, metastasis, and prognosis of patients with ovarian cancer. The use of HER2 inhibitors is a promising therapeutic strategy against chemoresistant ovarian cancer.


Assuntos
Actinas , Neoplasias Ovarianas , Feminino , Humanos , Actinas/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/metabolismo , Marcadores Genéticos , Células-Tronco Neoplásicas/metabolismo , Neoplasias Ovarianas/metabolismo , Fatores de Transcrição/genética , Prognóstico
3.
Int J Mol Sci ; 24(10)2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37240447

RESUMO

Methionine adenosyl transferases (MATs) catalyze the synthesis of the biological methyl donor adenosylmethionine (SAM). Dysregulation of MATs has been associated with carcinogenesis in humans. We previously found that downregulation of the MAT1A gene enriches the protein-associated translation process and worsens liver hepatocellular carcinoma (LIHC) prognosis. We also discovered that subcellular localization of the MAT2A protein has independently prognostic relevance in breast cancer patients. The present study aimed to examined the clinical relevance of MAT2A translocation in human LIHC. Essential methionine cycle gene expressions in TCGA LIHC datasets were analyzed using Gene Expression Profiling Interactive Analysis 2 (GEPIA2). The protein expression pattern of MAT2A was determined in the tissue array of our own LIHC cohort (n = 261) using immuno-histochemistry, and the prognostic relevance of MAT2A protein's subcellular localization expression was examined using Kaplan-Meier survival curves. LIHC patients with higher MAT2A mRNA expression had a worse survival rate (p = 0.0083). MAT2A protein immunoreactivity was observed in both cytoplasm and nucleus fractions in the tissue array. Tumor tissues had elevated MAT2A protein expression in both cytoplasm and nucleus compared to their adjacent normal tissues. A higher cytoplasmic to nuclear MAT2A protein expression ratio (C/N) was found in female LIHC patients compared to that of male patients (p = 0.047). Kaplan-Meier survival curves showed that a lower MAT2A C/N correlated with poor overall survival in female LIHC patients (10-year survival rate: 29.2% vs. 68.8%, C/N ≤ 1.0 vs. C/N > 1.0, log-rank p = 0.004). Moreover, we found that specificity protein 1 (SP1) may have a potential interaction with nuclear MAT2A protein, using protein-protein interaction; this we found using the GeneMANIA algorithm. We explored the possible protective effects of the estrogen axis in LIHC using the Human Protein Atlas (HPA), and found evidence supporting a possible protective effect of estrogen-related protein ESSRG in LIHC. The localization of SP1 and MAT2 appeared to be inversely associated with ESRRG expression in LIHC. The present study demonstrated the translocation of MAT2A and its prognostic relevance in female LIHC patients. Our findings suggest the potential of estrogen in SP1 regulation and localization of MAT2A, as therapeutic modalities against in female LIHC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Masculino , Feminino , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Prognóstico , S-Adenosilmetionina/metabolismo , Transferases , Metionina Adenosiltransferase/metabolismo
4.
J Biomed Sci ; 29(1): 42, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35706019

RESUMO

BACKGROUND: The development of drug resistance in oral squamous cell carcinoma (OSCC) that frequently leads to recurrence and metastasis after initial treatment remains an unresolved challenge. Presence of cancer stem cells (CSCs) has been increasingly reported to be a critical contributing factor in drug resistance, tumor recurrence and metastasis. Thus, unveiling of mechanisms regulating CSCs and potential targets for developing their inhibitors will be instrumental for improving OSCC therapy. METHODS: siRNA, shRNA and miRNA that specifically target keratin 17 (KRT17) were used for modulation of gene expression and functional analyses. Sphere-formation and invasion/migration assays were utilized to assess cancer cell stemness and epithelial mesenchymal transition (EMT) properties, respectively. Duolink proximity ligation assay (PLA) was used to examine molecular proximity between KRT17 and plectin, which is a large protein that binds cytoskeleton components. Cell proliferation assay was employed to evaluate growth rates and viability of oral cancer cells treated with cisplatin, carboplatin or dasatinib. Xenograft mouse tumor model was used to evaluate the effect of KRT17- knockdown in OSCC cells on tumor growth and drug sensitization. RESULTS: Significantly elevated expression of KRT17 in highly invasive OSCC cell lines and advanced tumor specimens were observed and high KRT17 expression was correlated with poor overall survival. KRT17 gene silencing in OSCC cells attenuated their stemness properties including markedly reduced sphere forming ability and expression of stemness and EMT markers. We identified a novel signaling cascade orchestrated by KRT17 where its association with plectin resulted in activation of integrin ß4/α6, increased phosphorylation of FAK, Src and ERK, as well as stabilization and nuclear translocation of ß-catenin. The activation of this signaling cascade was correlated with enhanced OSCC cancer stemness and elevated expression of CD44 and epidermal growth factor receptor (EGFR). We identified and demonstrated KRT17 to be a direct target of miRNA-485-5p. Ectopic expression of miRNA-485-5p inhibited OSCC sphere formation and caused sensitization of cancer cells towards cisplatin and carboplatin, which could be significantly rescued by KRT17 overexpression. Dasatinib treatment that inhibited KRT17-mediated Src activation also resulted in OSCC drug sensitization. In OSCC xenograft mouse model, KRT17 knockdown significantly inhibited tumor growth, and combinatorial treatment with cisplatin elicited a greater tumor inhibitory effect. Consistently, markedly reduced levels of integrin ß4, active ß-catenin, CD44 and EGFR were observed in the tumors induced by KRT17 knockdown OSCC cells. CONCLUSIONS: A novel miRNA-485-5p/KRT17/integrin/FAK/Src/ERK/ß-catenin signaling pathway is unveiled to modulate OSCC cancer stemness and drug resistance to the common first-line chemotherapeutics. This provides a potential new therapeutic strategy to inhibit OSCC stem cells and counter chemoresistance.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Queratina-17/metabolismo , MicroRNAs , Neoplasias Bucais , Animais , Carboplatina/farmacologia , Carboplatina/uso terapêutico , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Humanos , Integrina beta4/genética , Integrina beta4/metabolismo , Integrinas/genética , Integrinas/metabolismo , Integrinas/uso terapêutico , Queratina-17/genética , Queratina-17/farmacologia , Camundongos , MicroRNAs/farmacologia , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Plectina/genética , Plectina/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , beta Catenina/genética
5.
J Biomed Sci ; 29(1): 109, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550569

RESUMO

BACKGROUND: Ovarian cancer has the highest mortality among gynecological cancers due to late diagnosis and lack of effective targeted therapy. Although the study of interplay between cancer cells with their microenvironment is emerging, how ovarian cancer triggers signaling that coordinates with immune cells to promote metastasis is still elusive. METHODS: Microarray and bioinformatics analysis of low and highly invasive ovarian cancer cell lines were used to reveal periostin (POSTN), a matrix protein with multifunctions in cancer, with elevated expression in the highly invasive cells. Anchorage independent assay, Western blot, RNA interference, confocal analysis and neutralizing antibody treatment were performed to analyze the effects of POSTN on tumor promotion and to explore the underlying mechanism. Chemotaxis, flow cytometry and cytokine array analyses were undertaken to analyze the involvement of POSTN in cancer-associated fibroblast (CAF) and macrophage modulation. Correlations between POSTN expression levels and clinical characteristics were analyzed using the Oncomine, commercial ovarian cancer cDNA and China Medical University Hospital patient cohort. In vivo effect of POSTN on metastasis was studied using a mouse xenograft model. RESULTS: Expression of POSTN was found to be elevated in highly invasive ovarian cancer cells. We observed that POSTN was co-localized with integrin ß3 and integrin ß5, which was important for POSTN-mediated activation of ERK and NF-κB. Ectopic expression of POSTN enhanced whereas knockdown of POSTN decreased cancer cell migration and invasion in vitro, as well as tumor growth and metastasis in vivo. POSTN enhanced integrin/ERK/NF-κB signaling through an autocrine effect on cancer cells to produce macrophage attracting and mobilizing cytokines including MIP-1ß, MCP-1, TNFα and RANTES resulting in increased chemotaxis of THP-1 monocytes and their polarization to M2 macrophages in vitro. In agreement, tumors derived from POSTN-overexpressing SKOV3 harbored more tumor-associated macrophages than the control tumors. POSTN induced TGF-ß2 expression from ovarian cancer cells to promote activation of adipose-derived stromal cells to become CAF-like cells expressing alpha smooth muscle actin and fibroblast activation protein alpha. Consistently, increased CAFs were observed in POSTN overexpressing SKOV3 cells-derived metastatic tumors. In clinical relevance, we found that expression of POSTN was positively correlated with advanced-stage diseases and poor overall survival of patients. CONCLUSIONS: Our study revealed a POSTN-integrin-NF-κB-mediated signaling and its involvement in enhancing M2 macrophages and CAFs, which could potentially participate in promoting tumor growth. Our results suggest that POSTN could be a useful prognosis marker and potential therapeutic target.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Ovarianas , Feminino , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Integrinas/metabolismo , Fator de Crescimento Transformador beta2/metabolismo , Linhagem Celular Tumoral , Neoplasias Ovarianas/genética , Citocinas/metabolismo , Macrófagos/metabolismo , Microambiente Tumoral/genética
6.
Int J Mol Sci ; 23(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35008908

RESUMO

The major biological methyl donor, S-adenosylmethionine (adoMet) synthesis occurs mainly in the liver. Methionine adenosyltransferase 1A (MAT1A) and glycine N-methyltransferase (GNMT) are two key enzymes involved in the functional implications of that variation. We collected 42 RNA-seq data from paired hepatocellular carcinoma (HCC) and its adjacent normal liver tissue from the Cancer Genome Atlas (TCGA). There was no mutation found in MAT1A or GNMT RNA in the 42 HCC patients. The 11,799 genes were annotated in the RNA-Seq data, and their expression levels were used to investigate the phenotypes of low MAT1A and low GNMT by Gene Set Enrichment Analysis (GSEA). The REACTOME_TRANSLATION gene set was enriched and visualized in a heatmap along with corresponding differences in gene expression between low MAT1A versus high MAT1A and low GNMT versus high GNMT. We identified 43 genes of the REACTOME_TRANSLATION gene set that are powerful prognosis factors in HCC. The significantly predicted genes were referred into eukaryotic translation initiation (EIF3B, EIF3K), eukaryotic translation elongation (EEF1D), and ribosomal proteins (RPs). Cell models expressing various MAT1A and GNMT proved that simultaneous restoring the expression of MAT1A and GNMT decreased cell proliferation, invasion, as well as the REACTOME_TRANSLATION gene EEF1D, consistent with a better prognosis in human HCC. We demonstrated new findings that downregulation or defect in MAT1A and GNMT genes can enrich the protein-associated translation process that may account for poor HCC prognosis. This is the first study demonstrated that MAT1A and GNMT, the 2 key enzymes involved in methionine cycle, could attenuate the function of ribosome translation. We propose a potential novel mechanism by which the diminished GNMT and MAT1A expression may confer poor prognosis for HCC.


Assuntos
Carcinoma Hepatocelular/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Glicina N-Metiltransferase/genética , Neoplasias Hepáticas/genética , Metionina Adenosiltransferase/genética , Metionina/metabolismo , Biossíntese de Proteínas , Sequência de Bases , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Metilação de DNA/genética , Fator de Iniciação 3 em Eucariotos/metabolismo , Glicina N-Metiltransferase/metabolismo , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Metionina Adenosiltransferase/metabolismo , Invasividade Neoplásica , Fator 1 de Elongação de Peptídeos/metabolismo , Regiões Promotoras Genéticas/genética , Biossíntese de Proteínas/genética , Análise de Sobrevida
7.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065390

RESUMO

(1) Background: methionine cycle is not only essential for cancer cell proliferation but is also critical for metabolic reprogramming, a cancer hallmark. Hepatic and extrahepatic tissues methionine adenosyltransferases (MATs) are products of two genes, MAT1A and MAT2A that catalyze the formation of S-adenosylmethionine (SAM), the principal biological methyl donor. Glycine N-methyltransferase (GNMT) further utilizes SAM for sarcosine formation, thus it regulates the ratio of SAM:S-adenosylhomocysteine (SAH). (2) Methods: by analyzing the TCGA/GTEx datasets available within GEPIA2, we discovered that breast cancer patients with higher MAT2A had worse survival rate (p = 0.0057). Protein expression pattern of MAT1AA, MAT2A and GNMT were investigated in the tissue microarray in our own cohort (n = 252) by immunohistochemistry. MAT2A C/N expression ratio and cell invasion activity were further investigated in a panel of breast cancer cell lines. (3) Results: GNMT and MAT1A were detected in the cytoplasm, whereas MAT2A showed both cytoplasmic and nuclear immunoreactivity. Neither GNMT nor MAT1A protein expression was associated with patient survival rate in our cohort. Kaplan-Meier survival curves showed that a higher cytoplasmic/nuclear (C/N) MAT2A protein expression ratio correlated with poor overall survival (5 year survival rate: 93.7% vs. 83.3%, C/N ratio ≥ 1.0 vs. C/N ratio < 1.0, log-rank p = 0.004). Accordingly, a MAT2A C/N expression ratio ≥ 1.0 was determined as an independent risk factor by Cox regression analysis (hazard ratio = 2.771, p = 0.018, n = 252). In vitro studies found that breast cancer cell lines with a higher MAT2A C/N ratio were more invasive. (4) Conclusions: the subcellular localization of MAT2A may affect its functions, and elevated MAT2A C/N ratio in breast cancer cells is associated with increased invasiveness. MAT2A C/N expression ratio determined by IHC staining could serve as a novel independent prognostic marker for breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Metionina Adenosiltransferase/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Proliferação de Células/fisiologia , Feminino , Humanos , Linfonodos/metabolismo , Linfonodos/patologia , Metionina/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica/patologia , Prognóstico
8.
Int J Mol Sci ; 22(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34502300

RESUMO

Folate depletion causes chromosomal instability by increasing DNA strand breakage, uracil misincorporation, and defective repair. Folate mediated one-carbon metabolism has been suggested to play a key role in the carcinogenesis and progression of hepatocellular carcinoma (HCC) through influencing DNA integrity. Methylenetetrahydrofolate reductase (MTHFR) is the enzyme catalyzing the irreversible conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate that can control folate cofactor distributions and modulate the partitioning of intracellular one-carbon moieties. The association between MTHFR polymorphisms and HCC risk is inconsistent and remains controversial in populational studies. We aimed to establish an in vitro cell model of liver origin to elucidate the interactions between MTHFR function, folate status, and chromosome stability. In the present study, we (1) examined MTHFR expression in HCC patients; (2) established cell models of liver origin with stabilized inhibition of MTHFR using small hairpin RNA delivered by a lentiviral vector, and (3) investigated the impacts of reduced MTHFR and folate status on cell cycle, methyl group homeostasis, nucleotide biosynthesis, and DNA stability, all of which are pathways involved in DNA integrity and repair and are critical in human tumorigenesis. By analyzing the TCGA/GTEx datasets available within GEPIA2, we discovered that HCC cancer patients with higher MTHFR had a worse survival rate. The shRNA of MTHFR (shMTHFR) resulted in decreased MTHFR gene expression, MTHFR protein, and enzymatic activity in human hepatoma cell HepG2. shMTHFR tended to decrease intracellular S-adenosylmethionine (SAM) contents but folate depletion similarly decreased SAM in wildtype (WT), negative control (Neg), and shMTHFR cells, indicating that in cells of liver origin, shMTHFR does not exacerbate the methyl group supply in folate depletion. shMTHFR caused cell accumulations in the G2/M, and cell population in the G2/M was inversely correlated with MTHFR gene level (r = -0.81, p < 0.0001), MTHFR protein expression (r = -0.8; p = 0.01), and MTHFR enzyme activity (r = -0.842; p = 0.005). Folate depletion resulted in G2/M cell cycle arrest in WT and Neg but not in shMTHFR cells, indicating that shMTHFR does not exacerbate folate depletion-induced G2/M cell cycle arrest. In addition, shMTHFR promoted the expression and translocation of nuclei thymidine synthetic enzyme complex SHMT1/DHFR/TYMS and assisted folate-dependent de novo nucleotide biosynthesis under folate restriction. Finally, shMTHFR promoted nuclear MLH1/p53 expression under folate deficiency and further reduced micronuclei formation and DNA uracil misincorporation under folate deficiency. In conclusion, shMTHFR in HepG2 induces cell cycle arrest in G2/M that may promote nucleotide supply and assist cell defense against folate depletion-induced chromosome segregation and uracil misincorporation in the DNA. This study provided insight into the significant impact of MTHFR function on chromosome stability of hepatic tissues. Data from the present study may shed light on the potential regulatory mechanism by which MTHFR modulates the risk for hepatic malignancies.


Assuntos
Carcinoma Hepatocelular/patologia , Segregação de Cromossomos , DNA de Neoplasias/genética , Ácido Fólico/metabolismo , Metilenotetra-Hidrofolato Redutase (NADPH2)/antagonistas & inibidores , Uracila/metabolismo , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Instabilidade Cromossômica , DNA de Neoplasias/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Polimorfismo Genético , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas
9.
Hematol Oncol ; 38(3): 390-398, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32011024

RESUMO

BCR-ABL mutations are associated with resistance to tyrosine kinase inhibitors (TKIs) in Philadelphia chromosome-positive leukaemia. The emergence of these mutations in the era of second-generation TKIs, such as dasatinib and nilotinib, remains an evolving field. We conducted a retrospective study to quantitatively characterize the BCR-ABL transcript and mutation status during treatment with first-generation and second-generation TKI therapies. BCR-ABL mutations were detected by direct sequencing for patients with Philadelphia chromosome-positive leukaemia receiving TKI therapies. The efficacy of TKI therapy was quantitatively assessed by calculating the log reduction of BCR-ABL transcripts, which was measured using real-time quantitative polymerase chain reaction. Fisher's exact test was performed to analyse the associations of log reduction <3 and mutation status. We found 35 patients harbouring 55 mutations of 43 different types, of which 30% occurred in patients receiving imatinib, 27% in nilotinib, and 43% in dasatinib. We found a novel germline mutation, N336 N (AAC➔AAT), and two novel frameshift mutations, Asn358Thr fs*14 and Gly251Ala fs*16. T315I was the most common missense mutation, followed by V299L and F317L. Intron 8 35-bp insertion was the most frequent frameshift mutation. Both missense and multiple BCR-ABL mutations were significantly associated with worse molecular response compared with the molecular response of patients without mutation. Missense mutations, rather than frameshift, were associated with less log reduction, while the T315I, F317L, and T315A mutations were significantly correlated with poor log reduction. Collectively, amino acid substitutions at T315I, F317L, and T315A accounted for the majority of missense mutations and the loss of major molecular response. Mutation analysis is essential for patients receiving TKI therapy who exhibit an unfavourable response. The present study provided a landscape of BCR-ABL mutations in the era of second-generation TKIs.


Assuntos
Biomarcadores Tumorais/antagonistas & inibidores , Proteínas de Fusão bcr-abl/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Mutação , Cromossomo Filadélfia , Inibidores de Proteínas Quinases/uso terapêutico , Biomarcadores Tumorais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Seguimentos , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
10.
Cell Physiol Biochem ; 48(5): 2205-2218, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30110679

RESUMO

Background /Aims: Recent studies of microRNA (miRNA) involvement in tumorigenesis have indicated the critical role of these non-coding small RNAs in malignant transformation, but the prognostic role, if any, of miRNAs in breast cancer remains undetermined. Therefore, we assessed the prognostic significance of microRNA-9 (miR-9) and miR-221 in breast cancer toward the goal of understanding the contribution(s) of these miRNAs to cancer cell stemness. METHODS: The level of each of miR-9 and miR-221 in 206 paired laser capture microdissected tumor cells and non-tumor cells was determined by quantitative reverse transcription-PCR (qRT-PCR). The relationship between the miRNA signature and clinicopathological data and prognosis of breast cancer was assessed. Identification of a stem cell-enriched side population was achieved with fluorescence-activated cell sorting and a sphere-forming assay. Wound healing, Boyden chamber assays, and western blotting were used to study the contribution of each miRNA to tumor cell migration and invasion. RESULTS: We found that induction of miR-9 and miR-221 mimics conferred side-population cells to form spheroidal tumor colonies in suspension culture that maintained the mesenchymal stem-cell potential in non-invasive MCF-7 breast cancer cells. In contrast, knockdown of both miR-9 and miR-221 in invasive MDA-MB-231 breast cancer cells dramatically decreased the number of side-population colonies with stem cell-like potency, which reduced the capacity for tumor-cell renewal, invasion, and migration. Clinically, the mean proportion of miR-9- or miR-221-overexpressing cells was significantly greater in tumor cells compared with non-tumor cells (P < 0.05). Increased levels of miR-9 and miR-221 in breast tissue portended a significantly elevated risk of progression to malignancy with respect to larger tumor size, poor differentiation, late-stage evolution, lymph-node metastasis (P < 0.05), and lower overall survival (Ptrend = 0.017; eight-year follow-up). CONCLUSION: Our findings provide strong evidence that miR-9 and miR-221 can enhance the generation of cancer stem cells to yield an invasive phenotype and that overexpression of these miRNAs predicts a poor outcome for breast cancer patients.


Assuntos
Neoplasias da Mama/diagnóstico , MicroRNAs/metabolismo , Antígeno AC133/metabolismo , Adulto , Antagomirs/metabolismo , Área Sob a Curva , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Feminino , Humanos , Metástase Linfática , Células MCF-7 , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Pessoa de Meia-Idade , Proteína Homeobox Nanog/metabolismo , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Taxa de Sobrevida
11.
BMC Cancer ; 18(1): 219, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29471794

RESUMO

BACKGROUND: Cancer stem cells (CSCs) are believed to promote the malignant transformation of breast cancer via multiple signaling pathways, including the Wnt/ß-catenin pathway. Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) has been identified as a CSC-associated Wnt-regulated target gene, but its clinical significance in the context of breast cancer remains elusive. Therefore, the purpose of this study was to investigate the clinical significance of the LGR5-ß-catenin axis in breast cancer. METHODS: Breast cancer tissue blocks from 126 patients were used to construct a tissue microarray (TMA). Histopathological and clinical data including age; tumor size; estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) level; tumor grade; lymph node (LN) status; and survival were obtained from the cancer registry database and patients' medical records. Tissue on the breast TMA was scored for LGR5 and ß-catenin expression using semi-quantitative immunohistochemical (IHC) staining. We also analyzed LGR5 expression in cellular datasets available through ONCOMINE, a web-based cancer microarray database. RESULTS: Immunohistochemical staining revealed that 58 tumors (46%) exhibited high LGR5 expression, whereas 56 tumors (47%) displayed high ß-catenin expression. High levels of LGR5 expression were significantly associated with tumor size (p = 0.002), LN metastasis status (p = 0.044), and triple-negative breast cancer (p = 0.029), consistent with our findings from the ONCOMINE database. In addition, we also found that ß-catenin -expressing breast cancers were positive correlated with HER2 overexpression. Finally, with respect to clinical outcomes, patients with high levels of LGR5-ß-catenin axis expression exhibited poorer relapse-free survival (RFS) compared to patients with low levels of LGR5-ß-catenin axis expression (p = 0.027). CONCLUSION: LGR5 overexpression was significantly associated with high T stage and LN metastasis status. High LGR5 expression was also associated with reduced RFS, indicating that LGR5 may represent a promising prognostic marker for breast cancer patients.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Recidiva Local de Neoplasia , Receptores Acoplados a Proteínas G/genética , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/fisiologia , Prognóstico , Receptor ErbB-2/genética , Receptores Acoplados a Proteínas G/metabolismo , Regulação para Cima , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
12.
BMC Cancer ; 18(1): 609, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848298

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. The disease recurrent rate is relatively high resulted in poor 5-year survival in advanced HCC. Cancer stem cells (CSCs) have been considered to be one of the main mechanisms for chemoresistance, metastasis, and recurrent disease. Interferon-induced protein 44-like (IFI44L) gene is a type I interferon-stimulated gene (ISG) and belongs to the IFI44 family. Previous reports indicated antiviral activity against HCV in IFI44L, however, its precise role and function in HCC has not been unveiled. METHODS: To explore the characteristics of hepatic CSCs, we successfully enriched hepatic cancer stem-like cells from three established liver cancer cell lines (Hep3B, HepG2, and PLC lines). Parental Hep3B and HepG2 cells and their sphere cells were treated with doxorubicin for 48 h and cell viability was measured by MTT assay. HCC tissue blocks from 217 patients were sampled for tissue microarray (TMA). Follow-up information and histopathological and clinical data including age, gender, tumor grade, advanced stages, HBV, HCV, tumor number, tumor size, relapse-free survival, and overall survival were obtained from the cancer registry and medical charts. The liver TMA was evaluated for IFI44L expression using immunohistochemical staining and scores. RESULTS: These hepatic cancer stem-like cells possess important cancer stemness characteristics including sphere-forming abilities, expressing important HCC cancer stem cell markers, and more chemoresistant. Interestingly, we found that overexpression of IFI44L decreased chemoresistance towards doxorubicin and knockdown of IFI44L restored chemoresistance as well as promoted sphere formation. Furthermore, we found that depletion of IFI44L enhanced migration, invasion, and pulmonary metastasis through activating Met/Src signaling pathway. Clinically, the expression level of IFI44L significantly reduced in HCC tumor tissues. Low expression of IFI44L levels also correlated with larger tumor size, disease relapse, advanced stages, and poor clinical survival in HCC patients. CONCLUSION: Taken together, we first demonstrated that IFI44L is a novel tumor suppressor to affect cancer stemness, metastasis, and drug resistance via regulating Met/Src signaling pathway in HCC and can be serve as an important prognostic marker.


Assuntos
Carcinoma Hepatocelular/patologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidade , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Feminino , Técnicas de Silenciamento de Genes , Humanos , Fígado/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Masculino , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais/genética , Análise de Sobrevida , Análise Serial de Tecidos , Proteínas Supressoras de Tumor/genética , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases da Família src/metabolismo
14.
J Musculoskelet Neuronal Interact ; 18(1): 47-54, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29504578

RESUMO

OBJECTIVES: Extracorporeal shockwave therapy (ESWT) and corticosteroid injection (CSI) are treatment options for plantar fasciitis. Their clinical outcome comparison remains a debate. Also, the thickness changes of the plantar fascia on objective evaluation under the medium energy ESWT and CSI therapy are elusive. METHODS: A total of 97 patients with chronic plantar fasciitis were enrolled in the randomized prospective trial. Forty-seven patients received extracorporeal shock wave therapy (ESWT), and fifty patients received corticosteroid injection (CSI). The thickness of the plantar fascia was evaluated respectively before ESWT and CSI, and at the 4th and 12th week after ESWT and CSI by ultrasonography. Pain level and clinical outcomes were recorded using visual analogue scale (VAS) and 100-points scoring systems. Correlation analysis was performed between the thickness change and clinical outcome. RESULTS: Under ultrasonography, we observed more increase of plantar fascia thickness of ESWT group than CSI group at 4th week (p=0.048). VAS of plantar fasciitis patients receiving ESWT was lower than those who received corticosteroid injection (0.001 and p⟨0.001, at 4th and 12th week). On the assessment of 100-points scoring systems, the pain level of patients with ESWT was lower than those with CSI at the 12th week (p⟨0.001). On the other hand, the increase of plantar fascia thickness at 4th week was positively correlated with the decrease of VAS score at 12th week follow-up (R=0.302, P=0.039). CONCLUSIONS: At 4th week after treatment, the thickness of plantar fascia increased. Then it decreased gradually, but not to the baseline at 12th week. On the pain level outcome at 12th week, extracorporeal shockwave therapy (ESWT) was more efficient than corticosteroid injection (CSI) on chronic plantar fasciitis. The more change of plantar fascia after ESWT, the more efficient on clinical outcome.


Assuntos
Corticosteroides/uso terapêutico , Fáscia/diagnóstico por imagem , Fasciíte Plantar/diagnóstico por imagem , Fasciíte Plantar/terapia , Tratamento por Ondas de Choque Extracorpóreas , Fasciíte Plantar/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Ultrassonografia
15.
BMC Cancer ; 17(1): 474, 2017 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-28687090

RESUMO

BACKGROUND: CD133 (prominin-1) is widely believed to be a cancer stem cell marker in various solid tumor types, and CD133 has been correlated with tumor-initiating capacity. Recently, the nuclear location of CD133 expression in tumors has been discussed, but hepatocellular carcinoma (HCC) has not been included in these discussions. The goal of this study was to investigate the location of CD133 expression in HCC and this location's potential value as a prognostic indicator of survival in patients with HCC. METHODS: We enrolled 119 cancerous tissues and pair-matched adjacent normal liver tissue from HCC patients. These tissues were obtained immediately after operation, and tissue microarrays were subsequently constructed. The expression of CD133 was measured by immunohistochemistry (IHC), and the correlations between this expression and clinical characteristics and prognosis was estimated using statistical analysis. RESULTS: The results showed that the CD133 protein expression levels of HCC in both the cytoplasm and nucleus were significantly higher than adjacent normal liver tissue. Kaplan-Meier survival and Cox regression analyses revealed that high CD133 expression in the cytoplasm was an independent predictor of poor prognosis for the overall survival (OS) and relapse-free survival (RFS) rates of HCC patients (P = 0.028 and P = 0.046, respectively). Surprisingly, high nuclear CD133 expression of HCC was an independent predictor of the good prognosis of the OS and RFS rates of HCC patients (P = 0.023 and P = 0.012, respectively). CONCLUSIONS: The clinical evidence that revealed cytoplasmic CD133 expression was correlated with poor prognosis, while nuclear CD133 expression was significantly correlated with favorable prognosis.


Assuntos
Antígeno AC133/metabolismo , Biomarcadores Tumorais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Células-Tronco Neoplásicas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Células-Tronco Neoplásicas/patologia , Prognóstico , Modelos de Riscos Proporcionais , Transporte Proteico
16.
Pak J Pharm Sci ; 29(3 Suppl): 1071-5, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27383485

RESUMO

The epidemiological hip fracture leads to a high death rate in the elderly with osteoporosis worldwide. However, the appropriate surgical styles or anti-osteoporotic therapy could prevent these patients with hip fractures from suffering refracture, but the efficacy of such treatment remains elusive for first hip fractured patients. Our retrospective analysis was conducted on 508 hip fracture patients who were enrolled from Show Chwan Memorial Hospital from January 2005 through December 2011 and followed up until the end of 2012. However, bipolar hemiarthroplasty replacement and open reduction internal fixation (ORIF) are treatment options for femoral neck and intertrochanic hip fracture in our study population. Among these patients, 82 suffered 2nd hip fracture (refracture) with femoral neck or intertrochanteric fracture and 39 died after surgical intervention accompanied complications. Kaplan-Meier analysis revealed a better outcome in patients with bipolar hemiarthroplasty replacement or fosamax therapy of hip fractured patients than those with femoral neck/ORIF and intertrochanteric/ORIF or without fosamax therapy. Multivariate cox regression analysis revealed the lowest incidence of refracture and mortality in hip fracture patients with received bipolar hemiarthroplasty replacement surgical intervention (OR=0.732, CI=0.587-0.912; P=0.006). It is therefore concluded that fosamax therapy may improve bone density and increase bone tissue repair to prevent patients with hip fracture from refracture, and bipolar hemiarthroplasty replacement may promote patients who undertake outdoor activities to produce more vitamin D than those who have received ORIF.


Assuntos
Alendronato/uso terapêutico , Artroplastia de Quadril , Conservadores da Densidade Óssea/uso terapêutico , Fraturas do Colo Femoral/terapia , Fixação de Fratura , Hemiartroplastia , Fraturas por Osteoporose/terapia , Idoso , Alendronato/efeitos adversos , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/mortalidade , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/efeitos adversos , Distribuição de Qui-Quadrado , Feminino , Fraturas do Colo Femoral/diagnóstico , Fraturas do Colo Femoral/mortalidade , Fixação de Fratura/efeitos adversos , Fixação de Fratura/mortalidade , Hemiartroplastia/efeitos adversos , Hemiartroplastia/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/diagnóstico , Fraturas por Osteoporose/mortalidade , Modelos de Riscos Proporcionais , Recidiva , Estudos Retrospectivos , Fatores de Risco , Taiwan , Fatores de Tempo , Resultado do Tratamento
17.
Sensors (Basel) ; 14(8): 13361-88, 2014 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-25061837

RESUMO

Electroencephalogram-based emotion recognition (EEG-ER) has received increasing attention in the fields of health care, affective computing, and brain-computer interface (BCI). However, satisfactory ER performance within a bi-dimensional and non-discrete emotional space using single-trial EEG data remains a challenging task. To address this issue, we propose a three-layer scheme for single-trial EEG-ER. In the first layer, a set of spectral powers of different EEG frequency bands are extracted from multi-channel single-trial EEG signals. In the second layer, the kernel Fisher's discriminant analysis method is applied to further extract features with better discrimination ability from the EEG spectral powers. The feature vector produced by layer 2 is called a kernel Fisher's emotion pattern (KFEP), and is sent into layer 3 for further classification where the proposed imbalanced quasiconformal kernel support vector machine (IQK-SVM) serves as the emotion classifier. The outputs of the three layer EEG-ER system include labels of emotional valence and arousal. Furthermore, to collect effective training and testing datasets for the current EEG-ER system, we also use an emotion-induction paradigm in which a set of pictures selected from the International Affective Picture System (IAPS) are employed as emotion induction stimuli. The performance of the proposed three-layer solution is compared with that of other EEG spectral power-based features and emotion classifiers. Results on 10 healthy participants indicate that the proposed KFEP feature performs better than other spectral power features, and IQK-SVM outperforms traditional SVM in terms of the EEG-ER accuracy. Our findings also show that the proposed EEG-ER scheme achieves the highest classification accuracies of valence (82.68%) and arousal (84.79%) among all testing methods.


Assuntos
Eletroencefalografia/instrumentação , Eletroencefalografia/métodos , Emoções/fisiologia , Máquina de Vetores de Suporte , Interfaces Cérebro-Computador , Análise Discriminante , Humanos , Software
18.
Anticancer Res ; 44(1): 287-300, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38159982

RESUMO

BACKGROUND/AIM: Lung adenocarcinoma (LUAD) is the deadliest cancer, and approximately 20% of stage I LUAD cases recur after surgical resection due to its high intratumor heterogeneity. Reactive oxygen species (ROS) have been detected in LUAD and are involved in carcinogenesis and tumor progression. Here, a comprehensive analysis was performed to evaluate the effects of antioxidants on the prognosis of LUAD. MATERIALS AND METHODS: The Cancer Genome Atlas (TCGA) database was used to study the relationship of gene expression of different ROS-scavenging enzymes with the progression and prognosis of LUAD. RESULTS: Using TCGA LUAD datasets, we found that catalase (CAT) expression was significantly down-regulated in LUAD tissues compared to normal tissues, CAT down-regulation differed significantly between different grades of LUAD, low CAT expression was independently correlated with a worse prognosis in LUAD, and the expression of the CAT gene was associated with an inhibition of the "cell cycle". A panel of LUAD cells (CL1-0, CL1-1, CL1-3, and CL1-5), which harbored mutated p53 (R248W), with gradually increasing invasiveness showed a gradual decrease in CAT expression. Silencing of CAT upregulated cell growth in A549 cells, which harbor wild-type p53 and show high CAT expression and was associated with an increase in the expression of BUB1B, PLK1, and PKMYT1. Finally, over 38% (186/490) of LUAD cases with a p53 mutation exhibited significantly lower CAT expression than those with wild-type p53. CONCLUSION: CAT expression is a potent favorable prognostic marker for LUAD and may represent a drug target.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Prognóstico , Catalase/genética , Catalase/metabolismo , Proteína Supressora de Tumor p53 , Espécies Reativas de Oxigênio/metabolismo , Recidiva Local de Neoplasia , Adenocarcinoma de Pulmão/patologia , Proteínas de Membrana/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo
19.
Cancers (Basel) ; 16(3)2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38339408

RESUMO

Hypoxia-inducible factor 1α (HIF-1α) plays a pivotal role in the survival, metastasis, and response to treatment of solid tumors. Autophagy serves as a mechanism for tumor cells to eliminate misfolded proteins and damaged organelles, thus promoting invasiveness, metastasis, and resistance to treatment under hypoxic conditions. MicroRNA (miRNA) research underscores the significance of these non-coding molecules in regulating cancer-related protein synthesis across diverse contexts. However, there is limited reporting on miRNA-mediated gene expression studies, especially with respect to epithelial-mesenchymal transition (EMT) and autophagy in the context of hypoxic breast cancer. Our study reveals decreased levels of miRNA-622 (miR-622) and miRNA-30a (miR-30a) in invasive breast cancer cells compared to their non-invasive counterparts. Inducing miR-622 suppresses HIF-1α protein expression, subsequently activating miR-30a transcription. This cascade results in reduced invasiveness and migration of breast cancer cells by inhibiting EMT markers, such as Snail, Slug, and vimentin. Furthermore, miR-30a negatively regulates beclin 1, ATG5, and LC3-II and inhibits Akt protein phosphorylation. Consequently, this improves the sensitivity of invasive MDA-MB-231 cells to docetaxel treatment. In conclusion, our study highlights the therapeutic potential of inducing miR-622 to promote miR-30a expression and thus disrupt HIF-1α-associated EMT and autophagy pathways. This innovative strategy presents a promising approach to the treatment of aggressive breast cancer.

20.
Carcinogenesis ; 34(11): 2655-63, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23784082

RESUMO

Magnesium superoxide dismutase (SOD2) has been shown to cause dysfunction of p53 transcriptional activity, whereas, in turn, SOD2 expression is regulated by p53 to modulate lung tumorigenesis. In this study, we found that the level of SOD2 expression in a panel of lung cancer cells was negatively correlated with that of NK2 homeobox 1 (NKX2-1) but was not associated with p53 status. Mechanistic studies indicated that a decrease in NKX2-1 caused by SOD2-activated IKKß transcription was achieved by derepression of binding of Sp1 to the IKKß promoter. Immunoprecipitation, glutathione S-transferase pull-down experiments and electrophoretic mobility shift assays demonstrated a direct interaction between NKX2-1 and Sp1, blocking Sp1-mediated IKKß transcription. SOD2-mediated nuclear factor-kappaB activation, via elevation of IKKß transcription, promoted anchorage-independent soft-agar growth, invasion and xenograft tumor formation, because of development of the epithelial-to-mesenchymal transition. The expression level of NKX2-1 messenger RNA was negatively associated with the extent of SOD immunostaining and the IKKß messenger RNA expression level in lung tumors. The extent of SOD2 immunostaining and IKKß messenger RNA levels may independently predict overall survival and relapse-free survival in lung adenocarcinoma patients. In summary, we found that SOD2 activates nuclear factor-kappaB signaling by increasing IKKß transcription, which results in progression of lung adenocarcinoma and poorer patient outcomes. We suggest that IKKß may potentially be targeted to improve outcomes in patients with SOD2-positive tumors.


Assuntos
Adenocarcinoma/patologia , Quinase I-kappa B/genética , Neoplasias Pulmonares/patologia , NF-kappa B/metabolismo , Proteínas Nucleares/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Transcrição/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Animais , Western Blotting , Adesão Celular , Movimento Celular , Proliferação de Células , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Transição Epitelial-Mesenquimal , Feminino , Humanos , Quinase I-kappa B/metabolismo , Técnicas Imunoenzimáticas , Luciferases/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , NF-kappa B/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Superóxido Dismutase/genética , Fator Nuclear 1 de Tireoide , Fatores de Transcrição/genética , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53
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