粪肠球菌通过下调MOB3B促进结直肠癌的化疗耐药性OA

AIM:To investigate the contribution of Enterococcus faecalis(E.faecalis)to chemoresistance in colorectal cancer(CRC)and uncover the underlying mechanisms.METHODS:Bioinformatics analyses were performed to evaluate the expression of MOB3B,an Mps-one binder coactivator(MOB)protein family member,and its clinical impli-cations in CRC patients.E.faecalis was co-cultured with CRC cells to assess its effect on MOB3B expression.MOB3B was overexpressed or silenced in CRC cells to determine its effects on cell viability and chemosensitivity.The LRRC19-de-pendent mechanism was investigated through additional bioinformatics analyses.Immunohistochemical staining of clinical CRC tissues was performed to correlate MOB3B expression with Tumour Regression Grade.RESULTS:MOB3B down-regulation was associated with adverse clinicopathological characteristics and poor prognosis in CRC patients.Co-culture with E.faecalis down-regulated MOB3B expression in CRC cells.MOB3B overexpression decreased cell viability,while its silencing increased viability.MOB3B overexpression also reversed chemoresistance in CRC cells.Bioinformatics analy-ses revealed that MOB3B modulated resistance to oxaliplatin and 5-fluorouracil in an LRRC19-dependent manner.Low MOB3B expression correlated with high Tumour Regression Grade in clinical tissues.CONCLUSION:These findings in-dicate that Enterococcus faecalis promotes chemotherapy resistance by down-regulating MOB3B in colorectal cancer,and that MOB3B may serve as a potential marker for evaluating chemosensitivity and prognosis in CRC patients.The role of E.faecalis abundance as a clinical biomarker requires further validation in prospective cohorts.