MYC and DNMT3A-mediated DNA methylation represses microRNA-200b in triple negative breast cancer.

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.

A miR-26a/E2F7 feedback loop contributes to tamoxifen resistance in ER-positive breast cancer.

Tamoxifen (TAM) resistance is a substantial challenge in the treatment of estrogen receptor (ER)-positive breast cancer. Previous studies have revealed an important role of microRNA (miRNA/miR)-26a in TAM resistance in breast cancer. However, the mechanism underlying the regulatory effects of miR-26a on TAM resistance remains to be elucidated.

LCL161 increases paclitaxel-induced apoptosis by degrading cIAP1 and cIAP2 in NSCLC.

Background: LCL161, a novel Smac mimetic, is known to have anti-tumor activity and improve chemosensitivity in various cancers. However, the function and mechanisms of the combination of LCL161 and paclitaxel in non-small cell lung cancer (NSCLC) remain unknown.

Methods: Cellular inhibitor of apoptotic protein 1 and 2 (cIAP1&2) expression in NSCLC tissues and adjacent non-tumor tissues were assessed by immunohistochemistry.

OTUD7B and NIK expression in non-small cell lung cancer: Association with clinicopathological features and prognostic implications.

Purpose: To investigate the correlation among OTUD7B and NIK expression and the clinicopathological characteristics in NSCLC patients.

Methods: One hundred and twenty patients were involved in this study. We detected OTUD7B and NIK expression by immunohistochemistry and analyzed their correlation with clinicopathological data.

Fibronectin protects lung cancer cells against docetaxel-induced apoptosis by promoting Src and caspase-8 phosphorylation.

Fibronectin is involved in orchestrating many diverse cellular behaviors, including adhesion, invasion, differentiation, and proliferation and recently has also been shown to participate in the development of chemoresistance. In this study, we found that fibronectin expression was inversely correlated with clinical responses to docetaxel treatment in non-small cell lung cancer patients. Subsequently, we showed that fibronectin pretreatment could enhance cell viability and reduce apoptosis in docetaxel-treated lung cancer cells because fibronectin induced phosphorylated Src and caspase-8, rendering the later inactive, thus inhibiting docetaxel-induced apoptosis.

CDH1 promoter methylation correlates with decreased gene expression and poor prognosis in patients with breast cancer.

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.

[miR-101 inhibits the proliferation and migration of breast cancer cells via downregulating the expression of DNA methyltransferase 3a].

Objective: To investigate the effect of microRNA-101 (miR-101) on the proliferation and migration of breast cancer cells and its possible mechanism.

Methods: The expressions of miR-101 and DNA methyltransferase 3a (DNMT3a) in breast cancer tissues, corresponding normal breast tissues, breast cancer cells and normal breast cells were detected by real-time quantitative PCR. The lentiviral vectors containing miR-101 and shRNA-DNMT3a sequences were transfected into MDA-MB-231 cells to regulate the expressions of miR-101 and DNMT3a.

MiR-208a stimulates the cocktail of SOX2 and β-catenin to inhibit the let-7 induction of self-renewal repression of breast cancer stem cells and formed miR208a/let-7 feedback loop via LIN28 and DICER1.

MiR-208a stimulates cardiomyocyte hypertrophy, fibrosis and β-MHC (β-myosin heavy chain) expression, being involved in cardiovascular diseases. Although miR-208a is known to play a role in cardiovascular diseases, its role in cancer and cancer stem cells (CSCs) remains uncertain. We identified an inverse relationship between miR-208a and let-7a in breast cancer specimens, and found that SOX2, β-catenin and LIN28 are highly expressed in patients with advanced breast cancer opposed to lesser grades.

Let-7a regulates mammosphere formation capacity through Ras/NF-κB and Ras/MAPK/ERK pathway in breast cancer stem cells.

Breast cancer stem cells (BCSCs) have the greatest potential to maintain tumorigenesis in all subtypes of tumor cells and were regarded as the key drivers of tumor. Recent evidence has demonstrated that BCSCs contributed to a high degree of resistance to therapy. However, how BCSCs self renewal and tumorigenicity are maintained remains obscure.