The E-cadherin gene (CDH1) is associated with poor prognosis and metastasis in patients with breast cancer, and methylation of its promoter is correlated with decreased gene expression. However, there is currently no direct evidence that CDH1 promoter methylation indicates poor prognosis in patients with breast cancer. In the present study, methylation-specific polymerase chain reaction (PCR) was applied to detect the methylation status of the CDH1 promoter in 137 primary breast cancer, 85 matched normal breast tissue and 13 lung metastasis specimens. Reverse transcription-quantitative PCR was used to assess the relative expression levels of CDH1 mRNA, and correlation analysis between CDH1 methylation status, and gene expression, clinicopathological characteristics and patient survival was performed. Methylation of CDH1 was identified in 40.9% (56/137) of primary breast cancer specimens, 61.5% (8/13) of lung metastasis specimens and none of the matched normal breast specimens. The downregulation of CDH1 mRNA and E-cadherin protein expression were identified to be significantly correlated with CDH1 methylation (P<0.05). In addition, CDH1 methylation was significantly associated with lymph node metastasis and estrogen receptor status of patients (P<0.05). In univariate analyses, patients with CDH1 methylation exhibited poor overall survival (OS) and disease-free survival (DFS; P<0.05). Furthermore, multivariate analyses revealed that CDH1 methylation was an independent prognostic factor predicting poor OS (HR, 1.737; 95% CI, 0.957–3.766; P=0.041) and DFS (HR, 2.018; 95% CI, 2.057–3.845; P=0.033) in patients with breast cancer. Therefore, the present study suggests that CDH1 promoter methylation may be correlated with breast carcinogenesis and indicates poor prognosis in patients with breast cancer.
16 October 2018 in Journal of Cellular and Molecular Medicine
Triple‐negative breast cancer (TNBC) is the most aggressive breast cancer subtype with a poor prognosis. The microRNA‐200 (miR‐200) family has been associated with breast cancer metastasis. However, the epigenetic mechanisms underlying miR‐200b repression in TNBC are not fully elucidated. In this study, we found that MYC proto‐oncogene, bHLH transcription factor (MYC) and DNA methyltransferase 3A (DNMT3A) were highly expressed in TNBC tissues compared with other breast cancer subtypes, while miR‐200b expression was inhibited significantly. We demonstrated that MYC physically interacted with DNMT3A in MDA‐MB‐231 cells. Furthermore, we demonstrated that MYC recruited DNMT3A to the miR‐200b promoter, resulting in proximal CpG island hypermethylation and subsequent miR‐200b repression. MiR‐200b directly inhibited DNMT3A expression and formed a feedback loop in TNBC cells. MiR‐200b overexpression synergistically repressed target genes including zinc‐finger E‐box‐binding homeobox factor 1, Sex determining region Y‐box 2 (SOX2), and CD133, and inhibited the migration, invasion and mammosphere formation of TNBC cells. Our findings reveal that MYC can collaborate with DNMT3A on inducing promoter methylation and miR‐200b silencing, and thereby promotes the epithelial to mesenchymal transition and mammosphere formation of TNBC cells.
13 October 2021 in Journal of Experimental & Clinical Cancer Research
Background: SETD1A, a member of SET1/MLL family H3K4 methyltransferases, is involved in the tumorigenesis of numerous cancers. However, the biological role and mechanism of SETD1A in non-small cell lung cancer (NSCLC) remain to be elucidated.Methods: The expression of SETD1A, NEAT1, EZH2, and β-catenin in NSCLC tissues and cell lines was detected by qRT-PCR, immunohistochemistry and western blotting. The regulatory mechanisms were validated by chromatin immunoprecipitation, co-immunoprepitation and luciferase reporter assay. The self-renewal, cisplatin sensitivity and tumorigenesis of NSCLC cells were analyzed using sphere formation, CCK-8, colony formation assays and xenograft tumor models.Results: SETD1A expression was significantly increased in NSCLC and its overexpression predicted a poor prognosis of patients with NSCLC. Functional experiments showed that SETD1A positively regulated cancer stem cell property and negatively regulated cisplatin sensitivity in NSCLC cells via the Wnt/β-catenin pathway. Next, we found that SETD1A positively regulated the Wnt/β-catenin pathway via interacting with and stabilizing β-catenin. The SET domain is dispensable for the interaction between SETD1A and β-catenin. Furthermore, we identified that SETD1A bound to the promoters of NEAT1 and EZH2 to activate gene transcription by inducing H3K4me3 enrichment. Rescue experiments showed that SETD1A promoted the Wnt/β-catenin pathway and exerted its oncogenic functions in NSCLC, at least, partly through NEAT1 and EZH2 upregulation. In addition, SETD1A was proven to be a direct target of the Wnt/β-catenin pathway, thus forming a positive feedback loop in NSCLC cells.Conclusion: SETD1A and Wnt/β-catenin pathway form a positive feedback loop and coordinately contribute to NSCLC progression.
Lung cancer remains one of the most common cancer-associated mortalities worldwide, and platinum-based doublet chemotherapies are recommended as the first‑line treatment for advanced non‑small cell lung cancer (NSCLC). However, the frequent development of multidrug resistance, to cisplatin regimens in particular, is a major cause of chemotherapy failure in patients with aggressive NSCLC. Wnt/β‑catenin signaling and sex‑determining region Y box 2 (Sox2) have been implicated in the development and progression and resistance to epidermal growth factor receptor‑targeting therapy in lung cancer. The present study aimed to explore the effects of Wnt/β‑catenin and Sox2 signaling on the chemoresistance of cisplatin‑resistant lung cancer cells by assessing the effects of Sox2 on Wnt/β‑catenin signaling activity, cell migration, invasion and clonogenicity, and susceptibility to cisplatin in lung adenocarcinoma A549 cells and cisplatin-resistant A549/DDP cells. The results demonstrated that an enforced expression of Sox2 led to inhibition of Wnt/β-catenin signaling activity, potentially by upregulating glycogen synthase kinase 3 β in A549 and A549/DDP cells. An overexpression of Sox2 promoted cell migration and invasion, in addition to enhancing the clonogenic capacity in A549 cells. Notably, knockdown Sox2 using short hairpin RNA led to an enhanced susceptibility of A549 and A549/DDP cells to cisplatin, along with increased cell apoptosis. The present study thus suggests that Sox2 may be an important regulator in development of chemoresistance of lung cancer cells and may be a novel therapeutic target for treatment chemoresistant lung cancer.
Background. Sepsis-related acute kidney injury (S-AKI) is a frequent complication of hospitalized patients and is linked to increased morbidity and mortality. Early prediction and detection remain conducive to optimizing treatment strategies and limiting further insults. This study was aimed at evaluating the potential predictive value of the combined prognostic nutrition index (PNI) and neutrophil-to-lymphocyte ratio (NLR) to predict the risk of AKI in septic patients. Methods. In this retrospective study, 1238 adult patients with sepsis who were admitted to the First Affiliated Hospital of Xi’an Jiaotong University from January 2015 to June 2021 were enrolled. Patients were divided into two groups: the non-AKI group ( ) and the S-AKI group ( ). Univariate and multivariate logistic regression analyses were performed to screen the independent predictive factors of S-AKI. A receiver operating characteristic (ROC) curve was used to evaluate the predictive value of PNI and NLR. Results. Multivariate logistic regression analysis indicated that age, chronic liver disease, cardiovascular disease, respiratory rate (RR), white blood cells (WBC), blood urea nitrogen (BUN), creatinine (CRE), international normalized ratio (INR), neutrophil-to-lymphocyte ratio (NLR), and prognostic nutrition index (PNI) were independent prognostic factors of S-AKI. In the three models, the adjusted OR of PNI for S-AKI was 0.802 (0.776-0.829), 0.801 (0.775-0.829), and 0.717 (0.666-0.772), while that of NLR was 1.094 (1.078-1.111), 1.097 (1.080-1.114), and 1.044 (1.016-1.072), respectively. In addition, the area under the ROC curve of the PNI plus NLR group was significantly greater than that of the CRE plus BUN group (0.801, 95% CI: 0.775-0.827 vs. 0.750, 95% CI: 0.722-0.778, respectively; ). Conclusions. PNI and NLR have been identified as readily available and independent predictors in septic patients with S-AKI. PNI, in combination with NLR, is of vital significance for early warning and efficient intervention of S-AKI and is superior to combined BUN and CRE.
MiR-146a could stimulate tumor growth or block tumor proliferation in systemic malignancies, referring to the specific downstream targeted gene. However, its roles in breast cancer stem-like cells (BrCSCs) are barely known. To dig out its mechanistic functions, we explored the indicative roles of miR-146 in preclinical study, regardless of the hormone receptor status, and the positive correlation between miR-146 and better prognosis was proved, as its correlation to Let-7c was. To uncover the implicated mechanisms, we first identified the suppressive role of miR-146a in stem cells’ renewal, which was achieved by promoting the asymmetric division of BrCSCs. Let-7c was previously revealed with its suppressive functions in stem-like cells expansion, and miR-146 was predicated and successfully proved to bind to and degrade the 3’UTR of LIN28, a maturation blocker of Let-7 family. Results further showed that miR-146a increased the Let-7c level through degrading LIN28, and LIN28 inhibition is required for miR-146a induction of asymmetric stem cells’ division. Moreover, Let-7 controlled Wnt signaling pathway activity could be strengthened due to the miR146 inhibition of H19, later of which was often activated in stem cells group with functional existence of Wnt signaling. H19 itself in turn formed the positive feedback regulation with Let-7. Our results suggested the miR-146a/LIN28/Wnt signaling circle in restraining the symmetric cells division, which was specifically referred to the controlling of the small circle of Let-7c and H19, and together, this dual axis could help to prohibit the stem cells expansion.