Targeting miR-21 decreases expression of multi-drug resistant genes and promotes chemosensitivity of renal carcinoma.

Renal cell carcinoma, the most common neoplasm of adult kidney, accounts for about 3% of adult malignancies and is usually highly resistant to conventional therapy. MicroRNAs are a class of small non-coding RNAs, which have been previously shown to promote malignant initiation and progression. In this study, we focused our attention on miR-21, a well described oncomiR commonly upregulated in cancer.

Dual role of MUC1 mucin in kidney ischemia-reperfusion injury: Nephroprotector in early phase, but pro-fibrotic in late phase.

Acute kidney injury (AKI) is characterized by acute tubular necrosis (ATN) which involves mainly proximal tubules. Past AKI is associated with higher risk of chronic kidney disease (CKD). The MUC1 mucin is a large glycoprotein responsible for epithelial protection and locates to convoluted distal tubules and collecting ducts.

MUC1-C nuclear localization drives invasiveness of renal cancer cells through a sheddase/gamma secretase dependent pathway.

MUC1 is a membrane-anchored mucin and its cytoplasmic tail (CT) can interact with many signaling pathways and act as a co-transcription factor to activate genes involved in tumor progression and metastasis. MUC1 is overexpressed in renal cell carcinoma with correlation to prognosis and has been implicated in the hypoxic pathway, the main renal carcinogenetic pathway. In this context, we assessed the effects of MUC1 overexpression on renal cancer cells properties.

MUC1 drives epithelial-mesenchymal transition in renal carcinoma through Wnt/β-catenin pathway and interaction with SNAIL promoter.

MUC1 is overexpressed in human carcinomas. The transcription factor SNAIL can activate epithelial-mesenchymal transition (EMT) in cancer cells. In this study, in renal carcinoma, we demonstrate that (i) MUC1 and SNAIL were overexpressed in human sarcomatoid carcinomas, (ii) SNAIL increased indirectly MUC1 expression, (iii) MUC1 overexpression induced EMT, (iv) MUC1 C-terminal domain (MUC1-C) and β-catenin increased SNAIL transcriptional activity by interaction with its promoter and (v) blocking MUC1-C nuclear localization decreased Wnt/β-catenin signaling pathway activation and SNAIL expression.