https://www.selleckchem.com/products/PLX-4032.html Renal cell carcinoma (RCC) comprises a variety of pathological entities. Many RCCs are aggressive, demanding efficient targeted and immunetherapeutic strategies. Programmed cell death ligand-1 (PD-L1) is expressed mainly in hematopoietic cells and also in epithelial cells. The aim of this study was to correlate PD-L1 protein expression in a series of RCC tissues with their histo-pathological features. One hundred (n=100) archival, formalin-fixed and paraffin-embedded RCC tissue specimens were analysed by immunohistochemistry. Conventional tumor proportion score (TPS) qualitative assay was applied for evaluating protein expression levels. Based on the TPS evaluation, 8 (8%) cases were characterized as positive, and the rest of them (n=92; 92%) as negative. A progressive increase in PD-L1 positivity was significantly associated with the differentiation grade of the examined malignancies (p=0.001). Although PD-L1 over-expression is detected in low rates in RCCs, its correlation with differentiation grade should be considered as a factor for discriminating sub-groups of patients with specific histo-pathological features eligible for targeted anti-PD-L1 immunotherapy strategies. Although PD-L1 over-expression is detected in low rates in RCCs, its correlation with differentiation grade should be considered as a factor for discriminating sub-groups of patients with specific histo-pathological features eligible for targeted anti-PD-L1 immunotherapy strategies. Colorectal adenocarcinoma has a poor prognosis due to its propensity for metastasis. It has been experimentally demonstrated that the microRNA (miRNA) let-7a can effectively inhibit tumor proliferation and metastasis by regulating the transforming growth factor (TGF)-β signaling pathway; however, limited research has been conducted in the area of on colorectal cancer. Herein, we aimed to clarify the role and regulation of let-7a in a colorectal adenocarcinoma cell lin