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1.
Cell ; 148(5): 958-72, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22385961

RESUMO

Like many asymmetrically dividing cells, budding yeast segregates mitotic spindle poles nonrandomly between mother and daughter cells. During metaphase, the spindle positioning protein Kar9 accumulates asymmetrically, localizing specifically to astral microtubules emanating from the old spindle pole body (SPB) and driving its segregation to the bud. Here, we show that the SPB component Nud1/centriolin acts through the mitotic exit network (MEN) to specify asymmetric SPB inheritance. In the absence of MEN signaling, Kar9 asymmetry is unstable and its preference for the old SPB is disrupted. Consistent with this, phosphorylation of Kar9 by the MEN kinases Dbf2 and Dbf20 is not required to break Kar9 symmetry but is instead required to maintain stable association of Kar9 with the old SPB throughout metaphase. We propose that MEN signaling links Kar9 regulation to SPB identity through biasing and stabilizing the age-insensitive, cyclin-B-dependent mechanism of symmetry breaking.


Assuntos
Saccharomyces cerevisiae/citologia , Fuso Acromático/metabolismo , Proteínas de Ciclo Celular/metabolismo , Desoxirribonucleases/metabolismo , Metáfase , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , tRNA Metiltransferases/metabolismo
2.
J Pathol ; 259(2): 180-193, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36373877

RESUMO

Radiation enteritis (RE) is a prevalent complication of radiotherapy for pelvic malignant tumors, characterized by severe intestinal epithelial destruction and progressive submucosal fibrosis. However, little is known about the pathogenesis of this disease, and so far, there is no specific targeted therapy. Here, we report that CXCL16 is upregulated in the injured intestinal tissues of RE patients and in a mouse model. Genetic deletion of Cxcl16 mitigates fibrosis and promotes intestinal stem cell-mediated epithelial regeneration after radiation injury in mice. Mechanistically, CXCL16 functions on myofibroblasts through its receptor CXCR6 and activates JAK3/STAT3 signaling to promote fibrosis and, at the same time, to transcriptionally modulate the levels of BMP4 and hepatocyte growth factor (HGF) in myofibroblasts. Moreover, we find that CXCL16 and CXCR6 auto- and cross-regulate themselves in positive feedback loops. Treatment with CXCL16 neutralizing monoclonal antibody attenuates fibrosis and improves the epithelial repair in RE mouse model. Our findings emphasize the important role of CXCL16 in the progression of RE and suggest that CXCL16 signaling could be a potential therapeutic target for RE. © 2022 The Pathological Society of Great Britain and Ireland.


Assuntos
Quimiocina CXCL16 , Enterite , Lesões por Radiação , Animais , Camundongos , Quimiocina CXCL16/metabolismo , Enterite/etiologia , Enterite/metabolismo , Fibrose , Lesões por Radiação/genética , Receptores CXCR6 , Regeneração
3.
Cell Mol Biol Lett ; 28(1): 80, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828426

RESUMO

BACKGROUND: The mitochondrial gene MCCC2, a subunit of the heterodimer of 3-methylcrotonyl-CoA carboxylase, plays a pivotal role in catabolism of leucine and isovaleric acid. The molecular mechanisms and prognostic value still need to be explored in the context of specific cancers, including colorectal cancer (CRC). METHODS: In vitro and in vivo cell-based assays were performed to explore the role of MCCC2 in CRC cell proliferation, invasion, and migration. Mitochondrial morphology, membrane potential, intracellular reactive oxygen species (ROS), telomerase activity, and telomere length were examined and analyzed accordingly. Protein complex formation was detected by co-immunoprecipitation (CO-IP). Mitochondrial morphology was observed by transmission electron microscopy (TEM). The Cancer Genome Atlas (TCGA) CRC cohort analysis, qRT-PCR, and immunohistochemistry (IHC) were used to examine the MCCC2 expression level. The association between MCCC2 expression and various clinical characteristics was analyzed by chi-square tests. CRC patients' overall survival (OS) was analyzed by Kaplan-Meier analysis. RESULTS: Ectopic overexpression of MCCC2 promoted cell proliferation, invasion, and migration, while MCCC2 knockdown (KD) or knockout (KO) inhibited cell proliferation, invasion, and migration. MCCC2 KD or KO resulted in reduced mitochondria numbers, but did not affect the gross ATP production in the cells. Mitochondrial fusion markers MFN1, MFN2, and OPA1 were all upregulated in MCCC2 KD or KO cells, which is in line with a phenomenon of more prominent mitochondrial fusion. Interestingly, telomere lengths of MCCC2 KD or KO cells were reduced more than control cells. Furthermore, we found that MCCC2 could specifically form a complex with telomere binding protein TRF2, and MCCC2 KD or KO did not affect the expression or activity of telomerase reverse transcriptase (TERT). Finally, MCCC2 expression was heightened in CRC, and patients with higher MCCC2 expression had favorable prognosis. CONCLUSIONS: Together, we identified MCCC2 as a novel mediator between mitochondria and telomeres, and provided an additional biomarker for CRC stratification.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Telômero/genética , Telômero/metabolismo , Oncogenes , Mitocôndrias/metabolismo , Estimativa de Kaplan-Meier , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética
4.
Cell Commun Signal ; 20(1): 111, 2022 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-35870943

RESUMO

BACKGROUND: The screening biomarkers for early detection of colorectal cancer (CRC) is lacking. The aim is to identify epigenetic silenced genes and clarify its roles and underlying mechanism in CRC. We conducted integrative analyses of epigenome-wide Human Methylation 450 K arrays and transcriptome to screen out candidate epigenetic driver genes with transcription silencing. Methylated silencing HAND2 were identified and verified in large CRC cohort. The mechanism of HAND2 expression by promoter inhibition were clarified both in vitro and vivo assays. Cell biofunctional roles of HAND2 methylation was investigated in CRC cells. HAND2 reconstitution were constructed by lentivirus plasmid and tumor xenograft model of HAND2 were built subcutaneously. Genomic mRNA analysis by RNA-sequencing and subsequent GSEA analysis were performed to identify potential target of HAND2 and qPCR/WB was conducted to identify the results. RESULTS: We firstly reported high frequency of HAND2 methylation in promoter in CRC and hypermethylation was negatively correlated with expression silencing and leaded to poor survival in several CRC cohort patients. 5-Aza treatment to demethylated HAND2 could revert its expression in CRC cells. Functionally, HAND2 reconstitution can inhibit cell proliferation, invasion and migration in vitro. In tumor xenograft, HAND2 reconstruction significantly repressed tumor growth when compared to control vector. Thousands of aberrant expressed genes were observed in the heatmap of RNA-sequencing data. HAND2 reconstitution could bind to ERK and reduce its phosphorylation by CoIP assay. These above results showed HAND2 reconstitution perturbed the activation of MAPK/ERK signaling by reduction of ERK phosphorylation. CONCLUSIONS: HAND2 is one tumor suppressor by targeting ERK signaling and one potential epigenetic driver gene in CRC. Video Abstract.


Assuntos
Neoplasias Colorretais , Inativação Gênica , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Metilação de DNA/genética , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Humanos , RNA/metabolismo , Fatores de Transcrição/metabolismo
5.
Dig Dis Sci ; 63(1): 113-125, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29080145

RESUMO

BACKGROUND: Chronic radiation proctitis (CRP), a common complication after radiotherapy for pelvic malignancies, compromises patient quality of life. Vascular damage and aberrant angiogenesis in the mucosal layer are essential histological features, but changes to the submucosal layer are unclear. Thus, we evaluated the histological characteristics and distribution changes of key angiogenic factors in full-layered human CRP samples. METHODS: Thirty paraffin-embedded CRP and twenty-nine non-CRP tissues were used to evaluate histopathological changes. Immunohistochemistry with anti-CD34 antibody was performed to calculate microvascular density (MVD). Frozen tissues from eight CRP patients and five non-CRP controls were collected and analyzed by antibody array, which contained sixty human angiogenesis-related factors. Quality controls with positive and negative controls were performed during antibody array analysis. Two differentially expressed factors were confirmed by ELISA. RESULTS: CRP lesions showed vasculopathy, fibrosis, mucosal ulceration, edema, and inflammatory cell infiltration. Human angiogenesis antibody array and ELISA confirmed the increased angiostatin in CRP lesions. Immunohistochemical staining showed dispersed distribution of angiostatin throughout the mucosal and submucosal layers in CRP lesions, while angiostatin accumulated within the vessel lumens in non-CRP tissues. MVD significantly decreased in the submucosal layer of CRP, suggesting a potential association with increased angiostatin. CONCLUSIONS: Angiostatin increased and had a distinct distribution in CRP lesions. Compensatory telangiectasia in the mucosa, vessel stenosis, and reduced MVD might attenuate blood flow in the submucosa and contribute to CRP progression. Restoration of vascular functionality by promoting angiogenesis in the submucosal layer may help alleviate CRP in clinical practice.


Assuntos
Angiostatinas , Adulto , Idoso , Inibidores da Angiogênese/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica , Proctite/etiologia , Lesões por Radiação , Transcriptoma
7.
Future Oncol ; 13(17): 1473-1492, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28685592

RESUMO

AIM: To investigate the relationship between mutations of key genes in the EGFR signaling pathway and the prognosis of stage II colorectal cancer patients without chemotherapy. MATERIALS & METHODS: The incidence of KRAS, NRAS, BRAF, PIK3CA mutations and deficient DNA mismatch repair were assessed in 160 stage II colorectal cancer patients who had been treated by radical operation without adjuvant chemotherapy. RESULTS: Mutations in KRAS, BRAF or PIK3CA were associated with poor prognosis, while the deficient DNA mismatch repair status was not associated with the prognosis. Combining these three markers, the sensitivity of the predicted value for poor progression-free survival and overall survival reached 0.645 (p = 0.002) and 0.709 (p = 0.001), respectively. CONCLUSION: Knowing the mutation status of KRAS, BRAF or PIK3CA in stage II colorectal cancer can significantly improve the accuracy of prognoses.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Receptores ErbB/genética , Feminino , GTP Fosfo-Hidrolases/genética , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Prognóstico , Transdução de Sinais/genética
8.
Nucleic Acids Res ; 43(Database issue): D470-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25428363

RESUMO

The Biological General Repository for Interaction Datasets (BioGRID: http://thebiogrid.org) is an open access database that houses genetic and protein interactions curated from the primary biomedical literature for all major model organism species and humans. As of September 2014, the BioGRID contains 749,912 interactions as drawn from 43,149 publications that represent 30 model organisms. This interaction count represents a 50% increase compared to our previous 2013 BioGRID update. BioGRID data are freely distributed through partner model organism databases and meta-databases and are directly downloadable in a variety of formats. In addition to general curation of the published literature for the major model species, BioGRID undertakes themed curation projects in areas of particular relevance for biomedical sciences, such as the ubiquitin-proteasome system and various human disease-associated interaction networks. BioGRID curation is coordinated through an Interaction Management System (IMS) that facilitates the compilation interaction records through structured evidence codes, phenotype ontologies, and gene annotation. The BioGRID architecture has been improved in order to support a broader range of interaction and post-translational modification types, to allow the representation of more complex multi-gene/protein interactions, to account for cellular phenotypes through structured ontologies, to expedite curation through semi-automated text-mining approaches, and to enhance curation quality control.


Assuntos
Bases de Dados Genéticas , Redes Reguladoras de Genes , Mapeamento de Interação de Proteínas , Ácido Araquidônico/metabolismo , Doença/genética , Humanos , Internet
9.
Proc Natl Acad Sci U S A ; 110(39): 15716-21, 2013 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-24019491

RESUMO

Cyclin-dependent kinases (Cdks) are regulatory enzymes with temporal and spatial selectivity for their protein substrates that are governed by cell cycle-regulated cyclin subunits. Specific cyclin-Cdk complexes bind to and phosphorylate target proteins, coupling their activity to cell cycle states. The identification of specific cyclin-Cdk substrates is challenging and so far, has largely been achieved through indirect correlation or use of in vitro techniques. Here, we use a protein-fragment complementation assay based on the optimized yeast cytosine deaminase to systematically identify candidate substrates of budding yeast Saccharomyces cerevisiae Cdk1 and show dependency on one or more regulatory cyclins. We identified known and candidate cyclin dependencies for many predicted protein kinase Cdk1 targets and showed elusory Clb3-Cdk1-specific phosphorylation of γ-tubulin, thus establishing the timing of this event in controlling assembly of the mitotic spindle. Our strategy can be generally applied to identify substrates and accessory subunits of multisubunit protein complexes.


Assuntos
Ciclinas/metabolismo , DNA Polimerase III/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Modelos Biológicos , Ligação Proteica , Especificidade por Substrato , Tubulina (Proteína)/metabolismo
10.
Nucleic Acids Res ; 41(Database issue): D816-23, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23203989

RESUMO

The Biological General Repository for Interaction Datasets (BioGRID: http//thebiogrid.org) is an open access archive of genetic and protein interactions that are curated from the primary biomedical literature for all major model organism species. As of September 2012, BioGRID houses more than 500 000 manually annotated interactions from more than 30 model organisms. BioGRID maintains complete curation coverage of the literature for the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe and the model plant Arabidopsis thaliana. A number of themed curation projects in areas of biomedical importance are also supported. BioGRID has established collaborations and/or shares data records for the annotation of interactions and phenotypes with most major model organism databases, including Saccharomyces Genome Database, PomBase, WormBase, FlyBase and The Arabidopsis Information Resource. BioGRID also actively engages with the text-mining community to benchmark and deploy automated tools to expedite curation workflows. BioGRID data are freely accessible through both a user-defined interactive interface and in batch downloads in a wide variety of formats, including PSI-MI2.5 and tab-delimited files. BioGRID records can also be interrogated and analyzed with a series of new bioinformatics tools, which include a post-translational modification viewer, a graphical viewer, a REST service and a Cytoscape plugin.


Assuntos
Bases de Dados Genéticas , Redes Reguladoras de Genes , Mapeamento de Interação de Proteínas , Arabidopsis/genética , Arabidopsis/metabolismo , Humanos , Internet , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Interface Usuário-Computador
11.
Gastroenterol Rep (Oxf) ; 11: goad033, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37360194

RESUMO

Background: Aquaporin 9 (AQP9) is permeable to water or other small molecules, and plays an important role in various cancers. We previously found that AQP9 was related to the efficacy of chemotherapy in patients with colorectal cancer (CRC). This study aimed to identify the role and regulatory mechanism of AQP9 in CRC metastasis. Methods: The clinical significance of AQP9 was analysed by using bioinformatics and tissue microarray. Transcriptome sequencing, Dual-Luciferase Reporter Assay, Biacore, and co-immunoprecipitation were employed to demonstrate the regulatory mechanism of AQP9 in CRC. The relationship between AQP9 and CRC metastasis was verified in vitro and in vivo by using real-time cell analysis assay, high content screening, and liver metastasis models of nude mice. Results: We found that AQP9 was highly expressed in metastatic CRC. AQP9 overexpression reduced cell roundness and enhanced cell motility in CRC. We further showed that AQP9 interacted with Dishevelled 2 (DVL2) via the C-terminal SVIM motif, resulting in DVL2 stabilization and the Wnt/ß-catenin pathway activation. Additionally, we identified the E3 ligase neural precursor cell expressed developmentally downregulated 4-like (NEDD4L) as a modulator regulating the ubiquitination and degradation of AQP9. Conclusions: Collectively, our study revealed the important role of AQP9 in regulating DVL2 stabilization and Wnt/ß-catenin signaling to promote CRC metastasis. Targeting the NEDD4L-AQP9-DVL2 axis might have therapeutic usefulness in metastatic CRC treatment.

12.
Int J Biol Sci ; 18(4): 1677-1694, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35280699

RESUMO

Tumor necrosis factor α stimulated gene 6 (TSG-6), a 30-KD secretory protein, plays an essential role in modulating inflammatory responses and extracellular matrix remodeling. However, little is known regarding the role of TSG-6 in human cancers. Here, we investigated the mechanism of action and the role of TSG-6 in colorectal cancer (CRC) metastasis. We found that TSG-6 was highly expressed in tumor tissues and was associated with poor prognosis and metastasis in CRC. Mechanistically, TSG-6 overexpression in CRC cells resulted in ERK activation and epithelial-mesenchymal transition by means of stabilizing CD44 and facilitating the CD44-EGFR complex formation on the cell membrane. Consequently, this resulted in the promotion of tumor migration and invasion both in vitro and in vivo. Notably, our data showed that CRC cells secreted TSG-6 could trigger a paracrine activation of JAK2-STAT3 signaling and reprogram normal fibroblasts into cancer-associated fibroblasts, which exhibited upregulation of pro-metastatic cytokines (CCL5 and MMP3) and higher movement ability. In animal models, the co-injection of cancer cells and TSG6-reprogrammed fibroblasts led to a significant increase in tumor metastasis. Our findings indicated that TSG-6 overexpression in CRC cells could promote cancer metastasis in both an autocrine and paracrine manner. Therefore, targeting TSG-6 might be a potential therapeutic strategy for the treatment of metastatic CRC.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Colorretais , Animais , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Neoplasias Colorretais/metabolismo , Transição Epitelial-Mesenquimal/genética , Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Transdução de Sinais/genética , Microambiente Tumoral/genética
13.
Front Surg ; 9: 845148, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35548188

RESUMO

Background: Chronic radiation proctopathy (CRP) is a common complication after radiation therapy for pelvic malignancies. Compared with diversion surgery, resection surgery removes the damaged tissue completely to avoid the risks of recurrence and improve patients' outcome. Hence, resection surgery could be an optimal surgical approach when CRP is complicated by late complications. This study aimed to describe a modified surgical procedure of resection surgery and report its preliminary efficacy and safety in treating patients with CRP with late complications. Methods: We retrospectively reviewed the patients who were diagnosed with CRP with late complications and underwent the modified surgical procedure of laparoscopic proximally extended colorectal resection with two-Stage Turnbull-Cutait pull-through coloanal anastomosis (PE-Bacon) between November 2019 and October 2020 in the Sixth Affiliated Hospital of Sun Yat-sen University. Results: A total of 15 patients were performed the modified laparoscopic procedure of PE-Bacon, of which 1 patient underwent conversion from laparoscopic to open operation for intraoperative massive hemorrhage. Overall, the major (Clavien-Dindo III-V) postoperative complications occurred in 1 patient, anastomotic leakage was observed in 2 (13.3%) patients, and anastomotic stricture was observed in 4 (26.7%) patients. No patient had to be reoperated and died. Up to now, at the average follow-up of (524.40 ± 108.39) days, the preoperative symptoms of 93.3% (14/15) patients were relieved, with nine patients achieved complete remission, five patients only suffered minor symptoms. Because of the progression of radiation uropathy, one patient still had a vesicovaginal fistula as pre-operative complication. Colostomy reversal has been performed on 8 (53.3%) patients at an average postoperative duration of 299.5 ± 92.68 days, among whom only 2 patients suffered from major Low Anterior Resection Syndrome (LARS) until now. Conclusions: Laparoscopic PE-Bacon surgery is a safe and feasible surgical procedure for late complications of CRP with low morbidity and high symptom remission rate.

14.
Int J Biol Sci ; 18(5): 1912-1932, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342344

RESUMO

Patients with peritoneal metastasis (PM) of colorectal cancer (CRC) have poorer overall survival outcomes than those without PM. Cancer-associated fibroblasts (CAFs) are a major component of the tumor microenvironment and mediate CRC progression and PM. It is imperative to identify and develop novel therapeutic targets for PM-CRC driven by CAFs. Using lipidomics, we reveal that the abundance of phosphatidylcholine (PC) with unsaturated acyl chains was increased in clinical PM-CRC specimens. Additionally, we found that CAFs were present at a higher relative abundance in primary PM-CRC tumors and that membrane fluidity in CRC cells was increased after incubation with CAF-conditioned medium (CM) through three independent methods: lipidomics, fluorescence recovery after photobleaching (FRAP), and generalized polarization. Then, we found that increased membrane fluidity can enhance glucose uptake and metabolism, as supported by real-time bioenergetics analysis and U-13C glucose labeling. Interestingly, stearoyl-CoA desaturase 1 (SCD), the rate-limiting enzyme in the biosynthesis of unsaturated fatty acids (uS-FAs), was expressed at low levels in PM and associated with poor prognosis in CRC patients. Importantly, by untargeted metabolomics analysis and fatty acid ([U-13C]-stearic acid) tracing analyses, we found that CRC cells take up lipids and lipid-like metabolites secreted from CAFs, which may compensate for low SCD expression. Both in vitro and in vivo experiments demonstrated that sodium palmitate (C16:0) treatment could decrease the CAF-induced change in cell membrane fluidity, limit glucose metabolism, suppress cell invasiveness, and impair tumor growth and intraperitoneal dissemination. An increased C16:0 concentration was shown to induce apoptosis linked to lipotoxicity. Furthermore, C16:0 effectively enhanced the antitumor activity of 5-fluorouracil (5-FU) in vitro and was well tolerated in vivo. Taken together, these findings suggest that adding the saturated fatty acid (S-FA) C16:0 to neoadjuvant chemotherapy may open new opportunities for treating PM-CRC in the future.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Peritoneais , Fibroblastos Associados a Câncer/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias Colorretais/metabolismo , Humanos , Lipídeos , Fluidez de Membrana , Metabolômica , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/patologia , Microambiente Tumoral
15.
Heliyon ; 8(12): e12518, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36590511

RESUMO

Patient-derived xenograft (PDX) models are more faithful in maintaining the characteristics of human tumors than cell lines and are widely used in drug development, although they have some disadvantages, including their relative low success rate, long turn-around time, and high costs. The collagen gel droplet embedded culture drug sensitivity test (CD-DST) has been used as an in-vitro drug sensitivity test for patients with cancer because of its high success rate of primary cell culture, high sensitivity, and good clinical relevance, but it is based on an in-vitro cell culture and may not simulate the tumor microenvironment accurately. This study aims to combine a PDX model with CD-DST to evaluate the efficiency of antitumor agents. KRpep-2d, a small peptide targeting KRAS (G12D), and oxaliplatin were used to verify the feasibility of this approach. Whole-exome sequencing and Sanger sequencing were first applied to test and validate the KRAS mutation status of a panel of colorectal cancer PDX tissues. One PDX model was verified to carry KRAS (G12D) mutation and was used for in-vivo and the CD-DST drug tests. We then established the PDX mouse model from the patient with the KRAS (G12D) mutation and obtained viable cancer cells derived from the same PDX model. Next, the antitumor abilities of KRpep-2d and oxaliplatin were estimated in the PDX model and the CD-DST. We found that KRpep-2d showed no significant antitumor effect on the xenograft model or on cancer cells derived from the same PDX model. In contrast, oxaliplatin showed significant inhibitory effects in both tests. In conclusion, the PDX model in combination with the CD-DST assay is a comprehensive and feasible method of evaluating the antitumor properties of compounds and could be applied for new drug discovery.

16.
Transl Oncol ; 14(10): 101171, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34243012

RESUMO

BACKGROUND: The ORMDL1 gene is known as a crucial negative regulator of sphingolipid biogenesis. However, the ORMDL1 gene has rarely been studied in a tumor-related context. Therefore, its prognostic value and functional significance in colorectal cancer (CRC) remain to be explored. METHODS: TCGA CRC cohort analysis, qRT-PCR, and immunohistochemistry (IHC) were used to examine the ORMDL1 expression level. The association between ORMDL1 expression and various clinical characteristics was analyzed by chi-square tests. The overall survival (OS) of CRC patients was analyzed by Kaplan-Meier analysis. In vitro and in vivo cell-based assays were performed to explore the role of ORMDL1 in cell proliferation, invasion and migration. Transcriptional changes in cells with either ORMDL1 knockdown or overexpression were compared and analyzed. RESULTS: ORMDL1 was upregulated in CRC tissues in both the TCGA and our cohort. Interestingly, its expression was significantly lower in patients with metastasis than in patients without metastasis, and the high expression group had longer OS than the low expression group. Knockdown of ORMDL1 expression can promote proliferation, colony formation and invasion, while attenuating migration in CRC cell lines. In contrast, forced overexpression of ORMDL1 reduced cell proliferation, colony formation and invasion, while enhancing cell migration. Stable knockdown of ORMDL1 can promote cancer cell proliferation in vivo to some extent. Finally, Rho GTPase activity was influenced by ORMDL1, and the expression of ORMDL1 was enhanced by DTT treatment. CONCLUSION: ORMDL1 is upregulated and may serve as a biomarker to predict favourable outcomes in colorectal cancer.

17.
EClinicalMedicine ; 40: 101128, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34522874

RESUMO

BACKGROUND: The incidence of cardiovascular events in perioperative period of gastrointestinal tumor surgery cannot be ignored, and studies have shown that level of postoperative troponin is related to the postoperative risk of non-cardiac surgery. However, the relationship between pre-operative troponin levels and perioperative risk of gastrointestinal tumor surgery is unclear. Thus, we aimed to evaluate the value of high-sensitive cardiac troponin I (hs-cTnI) prior to gastrointestinal tumor surgery for perioperative risk assessment. METHODS: In this retrospective cohort study, 1259 patients who underwent gastrointestinal tumor surgery and had been tested for hs-cTnI on admission within 7 days prior to surgery were retrospectively recruited from January 2018 to June 2020. The primary combined endpoint including in-hospital all-cause mortality, acute myocardial infarction, cardiac arrest or ventricular fibrillation and acute decompensated heart failure. The secondary endpoint included total hospital stay and requirement of intensive care treatment. FINDINGS: Compared with patients with normal hs-cTnI, those with elevated hs-cTnI (> 0·028 ng/ml) were more likely to experience the combined endpoint (28·2% versus 2·7%, P < 0·001) and there was also an increasing rate of in mortality in elevated hs-cTnI group (2·4% versus 0·3%, P = 0·057). The length of total hospital stay was significantly longer in patients with elevated hs-cTnI (24·8 ± 16·3 versus 19·5 ± 7·9, P = 0·003) and the number of patients requiring intensive care treatment was also higher (22·6% versus 4·2%, P < 0·001). The area under the ROC curve assessing hs-cTnI in predicting in-hospital mortality was 0·787 [95% confidence interval (CI) 0·612-0·963, P = 0·015] and for combined endpoint was 0·822 [95% CI 0·766-0·879, P < 0·001]. Hs-cTnI > 0·028 ng/ml was associated with significantly higher cardiovascular event rate in patients with the revised cardiac index ≤ 1. The positive likelihood ratio of hs-cTnI (> 0·028 ng/ml) for predicting combined endpoint reaches 10.5 in patients with Lee index = 0. In multivariate logistic analyses, hs-cTnI was one of the best predictors for the combined endpoint [odds ratio (OR) 5·924 (95%CI: 2·869-12·233), P < 0·001]. INTERPRETATION: Hs-cTnI provides powerful prognostic information for patients undergoing gastrointestinal tumor surgery, and therefore provides reliable prognostic information incremental to revised cardiac index.

18.
Mol Oncol ; 15(5): 1391-1411, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33528867

RESUMO

Most cancer-related deaths result from the progressive growth of metastases. Patients with peritoneal metastatic (PM) colorectal cancer have reduced overall survival. Currently, it is still unclear why colorectal cancer (CRC) cells home to and proliferate inside the peritoneal cavity, and there is no effective consolidation therapy for improved survival. Using a proteomic approach, we found that key enzymes of fatty acid oxidation (FAO) were decreased in patients with PM colorectal cancer. Furthermore, we confirmed that carnitine palmitoyltransferase IA (CPT1A), a rate-limiting enzyme of FAO, was expressed at significantly low levels in patients with PM colorectal cancer, as determined by RT-qPCR, IHC, and GEO dataset analysis. However, lipidomics revealed no difference in FFA levels between PM and non-PM primary tumors. Here, we showed that cancer-associated fibroblasts (CAFs) promote the proliferation, migration, and invasion of colon cancer cells via upregulating CPT1A to actively oxidize FAs and conduct minimal glycolysis. In addition, coculture-induced glycolysis increased in cancer cells while fatty acid catabolism decreased with lower adiponectin levels. Importantly, inhibition of glycolysis significantly reduced the survival of CRC cells after incubation with conditioned medium from CAFsCPT1A-OE in vitro and impaired the survival and growth of organoids derived from CRC-PM. Finally, we found that directly blocking FAO in CAFsCPT1A-OE with etomoxir inhibits migration and invasion in vitro and decreases tumor growth and intraperitoneal dissemination in vivo, revealing a role for CAF CPT1A in promoting tumor growth and invasion. In conclusion, our results suggest the possibility of testing FAO inhibition as a novel approach and clinical strategy against CAF-induced colorectal cancer with peritoneal dissemination/metastases.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Neoplasias do Colo/patologia , Ácidos Graxos/metabolismo , Neoplasias Peritoneais/secundário , Microambiente Tumoral/fisiologia , Adolescente , Adulto , Idoso , Animais , Movimento Celular , Proliferação de Células , Células Cultivadas , Neoplasias do Colo/metabolismo , Feminino , Glicólise/fisiologia , Células HCT116 , Humanos , Metabolismo dos Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Oxirredução , Neoplasias Peritoneais/metabolismo , Regulação para Cima , Adulto Jovem
19.
Transl Oncol ; 13(12): 100874, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32947236

RESUMO

STUDY RATIONALE: The coexistence of KRAS and PIK3CA mutations in cells implies potential synergistic hyperactivation of the Ras/MAPK and PI3K/Akt oncogenic pathways. Therefore, it is desirable to investigate the concomitant mutations of KRAS and PIK3CA in colorectal cancer (CRC) samples and whether the concomitant mutations are associated with a poor prognosis in CRC patients. AIM: To investigate the clinicpathological characteristics and prognostic value of concomitant mutations of KRAS and PIK3CA in CRC samples. METHODS: In this study, a total of 655 CRC patients from the Sixth Affiliated Hospital of Sun Yat-sen University were enrolled from January to December 2015. Sanger sequencing was applied to survey the mutational status of hotspot regions in the open reading frames (ORFs) of the KRAS and PIK3CA genes. Clinicpathological parameters were collected and analyzed. The Kaplan-Meier method and Cox regression model were applied to determine the correlation between the KRAS and PIK3CA mutation statuses and survival. RESULTS: We found that KRAS and PIK3CA bi-mutations were significantly associated with aggressive clinicpathological features. Among the studied CRC patients, those with either KRAS mutations (P = 0.004) or KRAS and PIK3CA bi-mutations (P = 0.033) had poor overall survival (OS). In the multivariable analysis, KRAS mutations in exons 3 and 4 but not exon 2 with concomitant PIK3CA mutations were associated with a high risk of death (univariate HR = 8.05; 95% CI, 1.926-33.64, P = 0.004; multivariate HR = 10.505; 95% CI, 2.304-47.905, P = 0.002). CONCLUSION: The concomitant mutation statuses of KRAS and PIK3CA should be considered when the prognostic value of gene mutations is consulted in CRC patients.

20.
Gastroenterol Rep (Oxf) ; 8(4): 277-285, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32843974

RESUMO

BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) is associated with post-operative anastomotic complications in rectal-cancer patients. Anastomosis involving at least one non-irradiated margin reportedly significantly reduces the risk of post-operative anastomotic complications in radiation enteritis. However, the exact scope of radiotherapy on the remaining sigmoid colon remains unknown. METHODS: We evaluated the radiation damage of proximally resected colorectal segments in 44 patients with rectal cancer, who received nCRT followed by conventional resection (nCRT-C, n = 21) or proximally extended resection (nCRT-E, n = 23). The segments from another 13 patients undergoing neoadjuvant chemotherapy (nCT) were used as control. We dissected these samples at a distance of 2 cm between the two adjacent sections. Radiation damage in proximally resected colorectal segments was evaluated using the radiation injury score (RIS) and the concentration and distribution patterns of angiostatin. RESULTS: Compared to those in the nCT group, the nCRT group showed higher RIS, levels of angiostatin, and proportion of diffuse pattern of angiostatin. With increasing distance from the tumor site, these parameters all gradually decreased; and the differences came to be not significant at the site that is over 20 cm from the tumor. The nCRT-E group showed lower RIS (median: 2 vs 4, P = 0.002) and a greater proportion of non-diffuse angiostatin (87% vs 55%, P = 0.039) at the proximal margins compared with the nCRT-C group. CONCLUSIONS: The severity of the radiation damage of the proximal colon is inversely proportional to the proximal-resection margin length. Little damage was left on the proximal margin that was over 20 cm from the tumor. Removal of an initial length of ≥20 cm from the tumor may be beneficial for rectal-cancer patients after nCRT.

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