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Neoplasias , Neoplasias Gástricas , Humanos , Seguimentos , Estômago/diagnóstico por imagem , Estômago/cirurgia , Estômago/patologia , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Mucosa Gástrica/diagnóstico por imagem , Mucosa Gástrica/patologia , Estudos RetrospectivosRESUMO
BACKGROUND: Colorectal cancer remains one of the most common malignant tumors worldwide. Colorectal cancer initiating cells (CCICs) are a small subpopulation responsible for malignant behaviors of colorectal cancer. Aberrant activation of the Wnt pathways regulates the self-renewal of CCIC. However, the underlying mechanism(s) remain poorly understood. METHODS: Via retroviral library screening, we identified Nuclear Receptor-Interacting Protein 2 (NRIP2) as a novel interactor of the Wnt pathway from enriched colorectal cancer colosphere cells. The expression levels of NRIP2 and retinoic acid-related orphan receptor ß (RORß) were further examined by FISH, qRT-PCR, IHC and Western blot. NRIP2 overexpressed and knockdown colorectal cancer cells were produced to study the role of NRIP2 in Wnt pathway. We also verified the binding between NRIP2 and RORß and investigated the effect of RORß on CCICs both in vitro and in vivo. Genechip-scanning speculated downstream target HBP1. Western blot, ChIP and luciferase reporter were carried to investigate the interaction between NRIP2, RORß, and HBP1. RESULTS: NRIP2 was significantly up-regulated in CCICs from both cell lines and primary colorectal cancer tissues. Reinforced expression of NRIP2 increased Wnt activity, while silencing of NRIP2 attenuated Wnt activity. The transcription factor RORß was a key target through which NRIP2 regulated Wnt pathway activity. RORß was a transcriptional enhancer of inhibitor HBP1 of the Wnt pathway. NRIP2 prevented RORß to bind with downstream HBP1 promoter regions and reduced the transcription of HBP1. This, in turn, attenuated the HBP1-dependent inhibition of TCF4-mediated transcription. CONCLUSIONS: NRIP2 is a novel interactor of the Wnt pathway in colorectal cancer initiating cells. interactions between NRIP2, RORß, and HBP1 mediate a new mechanism for CCIC self-renewal via the Wnt activity.
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Neoplasias Colorretais/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Grupo de Alta Mobilidade/genética , Células-Tronco Neoplásicas/metabolismo , Proteínas do Tecido Nervoso/genética , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Proteínas Repressoras/genética , Regulação para Cima , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HT29 , Proteínas de Grupo de Alta Mobilidade/metabolismo , Humanos , Camundongos , Transplante de Neoplasias , Proteínas do Tecido Nervoso/metabolismo , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas Repressoras/metabolismo , Via de Sinalização WntRESUMO
OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) is becoming the most common chronic liver disease worldwide while still lacks drugs for treatment or prevention. We aimed to investigate the causal role of glucose-dependent insulinotropic polypeptide receptor agonists (GIPRAs) on NAFLD and identify the mediated risk factors by which GIPRAs exert their therapeutic effects. METHODS: Genetic proxies of GIPRAs were identified as cis-SNPs of GIPR associated with both the gene expression level and HbA1c and analyses including colocalization and linkage disequilibrium (LD) were performed for validation. We then performed two-sample two-step mendelian randomization to determine the causal effect of GIPRAs on NAFLD. RESULTS: The MR analysis suggested genetic proxies of GIPRAs were causally associated with reduced risk of NAFLD (Odds ratio (OR): 0.46, 95 % confidence interval (95 % CI): 0.24-0.88, P = 0.02) and T2DM (OR: 0.10, 95 % CI: 0.07-0.13, P < 0.01). In addition, Mediation analysis showed evidence of indirect effect of GIPRAs on NAFLD via TRIG (0.88, [0.85-0.92], P < 0.01) and HDL-C (0.85, [0.80-0.90], P < 0.01). CONCLUSIONS: Our study provided strong evidence to support the causal role of GIPRAs on reducing the risk of NAFLD probably through improving lipid metabolism, especially TG and HDL-C, providing guidance for future clinical trials.
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Hepatopatia Gordurosa não Alcoólica , Receptores dos Hormônios Gastrointestinais , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Desequilíbrio de Ligação , Análise de Mediação , Análise da Randomização Mendeliana , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Polimorfismo de Nucleotídeo Único , Receptores dos Hormônios Gastrointestinais/genéticaRESUMO
BACKGROUND: Minute gastric cancers (MGCs) have a favorable prognosis, but they are too small to be detected by endoscopy, with a maximum diameter ≤ 5 mm. AIM: To explore endoscopic detection and diagnostic strategies for MGCs. METHODS: This was a real-world observational study. The endoscopic and clinicopathological parameters of 191 MGCs between January 2015 and December 2022 were retrospectively analyzed. Endoscopic discoverable opportunity and typical neoplastic features were emphatically reviewed. RESULTS: All MGCs in our study were of a single pathological type, 97.38% (186/191) of which were differentiated-type tumors. White light endoscopy (WLE) detected 84.29% (161/191) of MGCs, and the most common morphology of MGCs found by WLE was protruding. Narrow-band imaging (NBI) secondary observation detected 14.14% (27/191) of MGCs, and the most common morphology of MGCs found by NBI was flat. Another three MGCs were detected by indigo carmine third observation. If a well-demarcated border lesion exhibited a typical neoplastic color, such as yellowish-red or whitish under WLE and brownish under NBI, MGCs should be diagnosed. The proportion with high diagnostic confidence by magnifying endoscopy with NBI (ME-NBI) was significantly higher than the proportion with low diagnostic confidence and the only visible groups (94.19% > 56.92% > 32.50%, P < 0.001). CONCLUSION: WLE combined with NBI and indigo carmine are helpful for detection of MGCs. A clear demarcation line combined with a typical neoplastic color using nonmagnifying observation is sufficient for diagnosis of MGCs. ME-NBI improves the endoscopic diagnostic confidence of MGCs.
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BACKGROUND: Observational studies have suggested an association between inflammatory bowel disease [IBD] and psoriasis. However, the detailed genetic basis, causality, and direction of this association remain unclear. METHODS: Bidirectional two-sample Mendelian Randomization [MR] analysis was conducted using summary statistics from published genome-wide association studies. Bayesian Colocalization and multivariable MR [MVMR] analyses were performed to identify candidate variants and risk genes involved in the shared genetic basis between IBD, psoriasis, and their subtypes. RESULTS: Genetically predicted IBD and Crohn's disease [CD] were associated with an increased risk of psoriasis, psoriasis vulgaris [PsV], and psoriatic arthritis [PsA] (IBD on psoriasis: pooled odds ratio [OR] 1.09, 95% confidence interval [CI] 1.04-1.14, p = .0001; CD on psoriasis: pooled OR 1.10, 95% CI 1.06-1.15, p < .0001) and vice versa (psoriasis on IBD: pooled OR 1.11, 95%CI 1.02-1.21), whereas CD only exhibited a unidirectional association with psoriasis. Colocalization analysis revealed eight candidate genetic variants and risk genes (including LINC00824, CDKAL1, IL10, IL23R, DNAJC27, LPP, RUNX3, and RGS14) associated with a shared genetic basis. Among these, IL23R, DNAJC27, LPP, and RGS14 were further validated by MVMR analysis. CONCLUSION: Our findings indicated bidirectional causal associations between IBD and psoriasis (including PsV and PsA), which were attributed primarily to CD rather than Ulcerative colitis [UC]. Furthermore, we identified several candidate variants and risk genes involved in the shared genetic basis of IBD and psoriasis. Acquiring a better understanding of the shared genetic architecture underlying IBD and psoriasis would help improve clinical strategies.
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Artrite Psoriásica , Doença de Crohn , Doenças Inflamatórias Intestinais , Psoríase , Humanos , Teorema de Bayes , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Doenças Inflamatórias Intestinais/genética , Psoríase/epidemiologia , Psoríase/genética , Doença de Crohn/genéticaRESUMO
Introduction: Colorectal cancer (CRC) ranks second for mortality and third for morbidity among the most commonly diagnosed cancers worldwide. We aimed to investigate the heterogeneity and convergence of tumor microenvironment (TME) in CRC. Methods: We analyzed the single-cell RNA sequencing data obtained from the Gene Expression Omnibus (GEO) database and identified 8 major cell types and 25 subgroups derived from tumor, para-tumor and peripheral blood. Results: In this study, we found that there were significant differences in metabolic patterns, immunophenotypes and transcription factor (TF) regulatory patterns among different subgroups of each major cell type. However, subgroups manifested similar lipid metabolic patterns, immunosuppressive functions and TFs module at the end of the differentiation trajectory in CD8+ T cells, myeloid cells and Fibroblasts. Meanwhile, TFs regulated lipid metabolism and immunosuppressive ligand-receptor pairs were detected by tracing the differentiation trajectory. Based on the cell subgroup fractions calculated by CIBERSORTx and bulk RNA-sequencing data from The Cancer Genome Atlas (TCGA), we constructed an immune risk model and clinical risk model of CRC which presented excellent prognostic value. Conclusion: This study identified that the differentiation was accompanied by remodeling of lipid metabolism and suppression of immune function, which suggest that lipid remodeling may be an important trigger of immunosuppression. More importantly, our work provides a new perspective for understanding the heterogeneity and convergence of the TME and will aid the development of prognosis and immunotherapies of CRC patients.
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Neoplasias Colorretais , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Análise da Expressão Gênica de Célula Única , Terapia de Imunossupressão , Imunossupressores , Neoplasias Colorretais/genética , LipídeosRESUMO
BACKGROUND: Colonic neuroendocrine carcinomas (co-NECs) are heterogeneous and aggressive, especially with regard to metastasis. Whether co-NECs on the right and left sides of the colon have different characteristics from colon adenocarcinoma is unknown. METHODS: The co-NEC patients were selected from the 2010-2017 Surveillance, Epidemiology, and End Results Program (SEER) database. The right and left sides of the colon were separated by the splenic flexure. Coarsened exact matching (CEM) was performed to adjust for relevant factors before regression models were constructed. RESULTS: A total of 669 pathologically diagnosed co-NEC patients with sufficient baseline data were identified from the SEER database. A total of 80.72% of the patients had co-NEC that originated from the right side of the colon, and their mean overall survival (mOS) was similar to that of the patients with left-sided co-NECs (right versus left: 22.30 m versus 22.55 m). A total of 44.84% of the patients were diagnosed with liver metastasis (46.68% right side versus 37.98% left side). In patients with liver metastasis, those with right-sided co-NECs had better survival than those with left-sided co-NECs (mOS right versus left: 15.37 m versus 9.62 m; adjusted hazard ratio (HR) = 0.69, 95% confidence interval (CI): 0.49-0.98, p = 0.035). To further investigate the survival benefits of primary site resection, we separated the patients who had liver metastasis according to the primary site and performed CEM to balance the groups (no patients underwent liver metastasis resection or intervention). The results suggested that primary surgery could benefit patients with both left- and right-sided co-NECs (adjusted HR = 0.50, 95% CI: 0.33-0.77, p = 0.001 on the right side; HR = 0.38, 95% CI: 0.16-0.89, p = 0.026 on the left side). CONCLUSIONS: Co-NECs frequently originate on the right side and commonly develop liver metastasis. Right-sided co-NECs are associated with better survival than left-sided co-NECs after liver metastasis has occurred. Primary site resection is associated with prolonged survival in co-NEC patients with liver metastasis, regardless of the side from which the co-NEC has originated.
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POLE mutations, which lead to an ultramutated phenotype in colorectal cancer (CRC), have been reported as a promising marker in immunotherapy. We performed sequencing of CRC cases in Zhejiang University (ZJU) and extracted obtainable data from recently published results, including The Cancer Genome Atlas (TCGA), Japanese studies and clinical trials, to present clinical patterns of POLE driver-mutated CRC and reveal its heterogeneity. The rate of somatic POLE driver mutations has been reported as 2.60% (ZJU cohort), 1.50% (TCGA cohort), 1.00% (Japan cohort), and 1.00% (Lancet cohort). POLE driver mutations show a clearly increased mutation burden (mean TMB: 217.98 mut/Mb in ZJU; 203.13 mut/Mb in TCGA). Based on pooled data, more than 70.00% of patients with POLE driver mutations were diagnosed before they were 55 years old and at an early disease stage (Stage 0-II >70.00%), and more than 70.00% were male. Among Asian patients, 68.40% developed POLE driver mutations in the left-side colon, whereas 64.00% of non-Asian patients developed them in the right-side colon (p < 0.01). The top three amino acid changes due to POLE driver mutations are P286R, V411L, and S459F. Investigators and physicians should ascertain the heterogeneity and clinical patterns of POLE driver mutations to be better equipped to design clinical trials and analyze the data.
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Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , DNA Polimerase II/genética , Heterogeneidade Genética , Mutação , Proteínas de Ligação a Poli-ADP-Ribose/genética , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Fatores de Risco , Fatores Sexuais , Adulto JovemRESUMO
Neuroendocrine tumors (NETs) are heterogeneous, and the incidence of NETs is rapidly increasing. We observed different survival in patients with rectal NETs and rectosigmoid junction NETs, which are treated similarly. We included patients with rectal and rectosigmoid junction NETs from the SEER database. The 5-year survival was set as the end-point. 6675 patients with rectal NETs and 329 patients with rectosigmoid junction NETs, were eligible for the analysis. Initially, the survival analyses suggested that the 5-year survival significantly differed between the patients with rectal and rectosigmoid junction NETs (HR = 0.82, 95% CI 0.70-0.95; P = .01). Tumor differentiation, an invasion deeper than T2, and lymph node and distant metastases were still important risk factors affecting survival for both location. While, the males showed better survival (HR = 0.69, 95% CI 0.55-0.88; P < .01) and primary tumor surgery had no benefits (P = .56) for patients with rectosigmoid junction NETs. The factors that predict regional lymph node metastases varied by location. In rectal NETs, invasion deeper than T1 and a tumor larger than 1 cm could significantly increase the risk of regional lymph node metastases (all OR > 5, P < .01). In rectosigmoid junction NETs, the risk of regional lymph node metastases was considered significantly higher with invasion deeper than T1 (all OR > 5, P < .01) and a tumor larger than 2 cm (OR = 31.32, 95% CI 2.53-387.57; P < .01). We advocate a clear and consistent definition of the rectosigmoid junction for future studies, and more studies are needed to determine the reason underlying differences between rectum and rectosigmoid junction.
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Colo Sigmoide/patologia , Tumores Neuroendócrinos/terapia , Neoplasias Retais/terapia , Reto/patologia , Neoplasias do Colo Sigmoide/terapia , Adulto , Idoso , Quimiorradioterapia Adjuvante/normas , Colectomia/normas , Colo Sigmoide/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfonodos , Metástase Linfática/diagnóstico , Metástase Linfática/terapia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Terapia Neoadjuvante/normas , Invasividade Neoplásica , Estadiamento de Neoplasias , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/patologia , Guias de Prática Clínica como Assunto , Protectomia/normas , Neoplasias Retais/diagnóstico , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Reto/cirurgia , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Programa de SEER/estatística & dados numéricos , Fatores Sexuais , Neoplasias do Colo Sigmoide/diagnóstico , Neoplasias do Colo Sigmoide/mortalidade , Neoplasias do Colo Sigmoide/patologia , Taxa de SobrevidaRESUMO
Tumor-infiltrating lymphocytes (TILs) in gastric cancer are closely related to clinical prognosis; however, little is known regarding the immune microenvironment in this disease. Thus, RNA-sequencing data from gastric cancer patients were downloaded from the Gene Expression Omnibus (GEO). The proportion of immune cells was determined based on a deconvolution algorithm (CIBERSORT), and gene expression profiles were analyzed in the context of clinical outcomes to construct an immune risk score. Data were analyzed using least absolute shrinkage and selection operator (LASSO) and multivariable Cox regression, to identify prognostic markers of gastric cancer survival. The model included four immune cell types: neutrophils, plasma cells, activated CD4+ memory T cells, and T follicular helper cells. Patients were classified into two subgroups based on risk score, and a significant difference in overall survival (OS) was seen between the subgroups in both the training and testing cohorts, particularly in patients with tumor stages ≥T3. Multivariable analysis revealed that both T-stage and risk score were independent prognostic factors for gastric cancer survival [hazard ratio (HR) 1.505; 95% confidence interval (CI) 1.043-2.173, HR 1.686; 95% CI 1.367-2.080]. Risk scores and clinical factors were then integrated into a nomogram to build a model with both good discriminatory power and accuracy in predicting clinical outcomes. Further analysis using gene set enrichment analysis (GSEA) identified strong associations of immune risk with TGF-ß and tumor metastasis-related pathways, which could inform research on the molecular mechanisms of gastric cancer. Collectively, the data presented here suggest that an immune risk model can make an important contribution to predictions prognosis in gastric cancer patients.
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OBJECTIVE: Although N6-methyladenosine (m6A) RNA methylation is the most common mRNA modification process, few studies have examined the role of m6A in stomach adenocarcinomas (STADs). METHODS: In this retrospective study, we analyzed 293 STAD samples from The Cancer Genome Atlas with complete clinicopathological feature profiles. The m6A methylation risk signature was derived from LASSO-Cox regression analyses with 15 m6A regulators. Statistical analysis was performed and figures were prepared using R software (https://www.R-project.org/). RESULTS: The m6A signature was established as follows: risk score = FTO × 0.127 + YTHDF1 × 0.004 + KIAA1429 × 0.044 + YTHDC2 × 0.112 - RBM15 × 0.135 - ALKBH5 × 0.019 - YTHDF2 × 0.028, which was confirmed as an independent prognostic indicator to predict overall survival of patients with STAD. Risk scores and tumor grades were closely associated. Cell cycle, p53 signaling pathways, DNA mismatch repair, and RNA degradation were enriched in the low-risk subgroup. This subgroup showed significantly higher expression of immune checkpoint molecules including PD-1 (programmed death 1), PD-L1 (programmed death-ligand 1), and CTLA-4 (cytotoxic T-lymphocyte-associated antigen 4), suggesting that the signature may be a useful immunotherapy predictor. CONCLUSIONS: We established an m6A methylation signature as an independent prognostic tool to predict overall survival, which may also be useful as an immunotherapy predictor.
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Adenocarcinoma , Proteínas de Checkpoint Imunológico , Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Adenosina/análogos & derivados , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Humanos , Metilação , RNA , RNA Helicases , Estudos Retrospectivos , EstômagoRESUMO
Overexpression of multidrug resistance proteins (Mdrs) and enhanced antiapoptotic capability are two of the main mechanisms by which Bcr/Abl(+) chronic myeloid leukemia cells acquire drug resistance; however, it has been shown that Mdr-1 expression provides minimal protection against cell apoptosis induced by chemotherapeutic drugs. The mechanism by which cells acquire an enhanced antiapoptosis capacity in the drug-resistant process needs to be further understood. Here, we identified human brain expressed X-linked 1 (hBex1) as a downstream target of the p75 neurotrophin receptor pathway in imatinib-resistant K562 cells by comparing the gene expression profiles with the parent K562 cells. Silencing hBex1 inhibited imatinib-induced cell apoptosis and overexpression of hBex1-sensitized cells to imatinib-induced apoptosis. Further investigation revealed that hBex1 associates with protocadherin 10 (PCDH10). Silencing of pcdh10 attenuated apoptosis induced by imatinib in hBex1 transfected cells, suggesting that, in addition to Mdr and Bcl-2 family members, reduced expression of hBex1 can also inhibit imatinib-induced apoptosis. These data provide evidence that expression of hBex1 in leukemic cells is a novel mechanism by which chemoresistance is achieved and suggests that hBex1 is a potential molecular target for the development of novel leukemia treatments.
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Apoptose/fisiologia , Regulação para Baixo , Genes abl , Leucemia/patologia , Proteínas do Tecido Nervoso/fisiologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Inativação Gênica , Humanos , Leucemia/genética , Leucemia/fisiopatologia , Proteínas do Tecido Nervoso/genética , RNA Interferente PequenoRESUMO
Hepatoma-derived growth factor (HDGF) is related to tumorigenesis and the development of cancer; it is an independent factor associated with the prognosis of liver cancer, non-small cell lung cancer and pancreatic cancer. However, the molecular mechanism by which HDGF participates in gastric carcinogenesis and development as well as its functional regulation during the development of gastric precancerous lesions needs to be further analyzed. In the present study, we analyzed the effect of HDGF transfection on the proliferation and on the changes of mitogen-activated protein kinase (MAPK), Akt, and nuclear factor-kB (NF-kB) pathways in gastric cancer AGS cells. HDGF transfection significantly activated Erk1/2 in AGS cells and promoted anchorage-independent growth. Further studies showed that HDGF expression gradually increased in the gastric carcinogenesis process and HDGF showed a high expression in poorly differentiated adenocarcinoma prone to lymphoid metastasis; these findings suggest that HDGF is involved in the gastric carcinogenesis process and promotes proliferation and metastasis via Erk1/2 activation.
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Transformação Celular Neoplásica/metabolismo , Mucosa Gástrica/enzimologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neoplasias Gástricas/enzimologia , Adenocarcinoma/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Mucosa Gástrica/patologia , Humanos , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , TransfecçãoRESUMO
Cancer Stem-like Cells (CSCs) are a subpopulation of cancer cells with self-renewal capacity and are important for the initiation, progression and recurrence of cancer diseases. The metabolic profile of CSCs is consistent with their stem-like properties. Studies have indicated that enzymes, the main regulators of cellular metabolism, dictate functionalities of CSCs in both catalysis-dependent and catalysis-independent manners. This paper reviews diverse studies of metabolic enzymes, and describes the effects of these enzymes on metabolic adaptation, gene transcription and signal transduction, in CSCs.
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Células-Tronco Neoplásicas/metabolismo , Animais , Humanos , Transdução de Sinais/fisiologiaRESUMO
Colorectal cancer (CRC) is one of the most common types of malignant tumor in the world and occurs through a multi-step process resulting from the accumulation of genetic and epigenetic alterations of the genome. Although the molecular mechanisms of the pathogenesis of CRC remain unclear, the inactivation of tumor suppressor genes (TSGs) through promoter methylation serves an important role. Aberrant methylation is a well-defined marker of CRC. At present, the epigenetic silencing of protocadherin 10 (PCDH10) has been identified as an important TSG with key roles in colorectal carcinogenesis, invasion and metastasis as a frequent and early event. Advances in gene methylation detection in tumor tissues and body fluids have led to the development of non-invasive screening methods for CRC. The present study aimed to review the epigenetic alteration of PCDH10 in CRC development, and the potential of PCDH10 to be a non-invasive biomarker for CRC.
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OBJECTIVE: To investigate the effects of novel triterpene (12-oleanene-3beta, 6alpha-diol) from Celastrus hypoleucus on the proliferation and apoptosis of human colorectal cancer cell line RKO. METHOD: The inhibitory effect of the novel triterpene on RKO cell proliferation was assayed by MTT dye reduction. The morphology of apoptotic cells was observed with AO/EB double fluorescence staining and HE staining, DNA fragment with electrophoresis on agarose gels, sub-diploid peak and cell cycle with flow cytometer (FCM). RESULT: Novel triterpene (12-oleanene-3beta, 6alpha-diol) from C. hypoleucus significantly inhibited proliferation of RKO cells in dose-dependent and time-dependent manner, the IC50 was (12.20 +/- 0.79) microg x mL(-1) at 48 h. Typical apoptotic changes were observed in RKO cells under the fluorescence microscope and the light microscope. DNA ladder was detected on agarose gels at concentrations from 10 microg x mL(-1) to 20 microg x mL(-1) at 48 h. With FCM methods, dose-dependent apoptosis-induced effect was observed in RKO cell line after treatment of triterpene for 48 h, and the apoptotic rates were increased from(2.93 +/- 0.84) % to (50.79 +/- 6.61) % at concentrations from 2.5 microg x mL(-1) to 20 microg x mL(-1). DNA histograms data from FCM analysis showed that the number of cells was obviously reduced during G0-G1 phase and G2-M phase, but not during S phase for RKO cell line after treatment with various concentrations of the triterpene for 48 hours. CONCLUSION: Novel triterpene (12-oleanene-3beta, 6alpha-diol) from C. hypoleucus can induce apoptosis and has inhibition effect on the proliferation in RKO cell line.
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Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Celastrus/química , Neoplasias Colorretais/patologia , Ácido Oleanólico/análogos & derivados , Antineoplásicos Fitogênicos/isolamento & purificação , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Concentração Inibidora 50 , Ácido Oleanólico/administração & dosagem , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Caules de Planta/química , Plantas Medicinais/químicaRESUMO
Pancreatic cancer is one of the more common cancers with a poor prognosis. Some varieties of cancer are related to virus infection. As a virus-induced protein, APOBEC3G (A3G) presents extensive anti-virus ability, but the role of A3G in pancreatic cancer was previously unknown. The expression of A3G in pancreatic cancer was examined using TaqMan real-time qPCR, immunohistochemical and immunofluorescent staining. Subsequently, the role of A3G in pancreatic cancer was evaluated in vivo using the tumor xenograft model. Anoikis was detected by colony formation assay and flow cytometry in vitro. The Akt kinase activity and target protein PTEN were examined by co-immunoprecipitation and immunoblot. The virus-induced protein A3G was significantly up-regulated in pancreatic cancer, and the up-regulation of A3G promoted xenograft tumor formation. A3G inactivated PTEN by binding to the C2 tensin-type and PDZ domains, thereby inducing anoikis resistance through Akt activation. Our results demonstrate that the up-regulation of A3G in pancreatic cancer cells induces anoikis resistance, and they provide novel insight into the mechanism by which A3G affects the malignant behavior of pancreatic cancer cells.