No abstract

Non-small cell lung cancer (NSCLC) remains one of the most common malignant tumors worldwide. The aim of the present study was to investigate the possibility of microRNA-20a (miR-20a) as a biomarker and therapeutic target for the diagnosis and treatment of NSCLC. Bioinformatics prediction, together with functional validation, confirmed miR-20a bound to programmed death ligand-1 (PD-L1) 3'-untranslated region to upregulate PD-L1 expression. Both miR-20a and PD-L1 could promote the proliferation of NSCLC cells. The expression level of PD-L1 was controlled by PTEN; however, further upstream regulation of PD-L1 expression was largely unknown. The present study showed that miR-20a could not restore the inhibition of PD-L1 expression levels by PTEN. Knockdown of PTEN expression upregulated the expression level of PD-L1 and promoted the proliferation of NSCLC cells. PTEN negatively regulated the Wnt/β-catenin signaling pathway by inhibiting β-catenin and Cyclin D1. Interestingly, PTEN could reverse miR-20a-mediated proliferation of NSCLC cells and the inhibitory effect was similar to that of XAV-939. miR-20a promotes the proliferation of NSCLC cells by inhibiting the expression level of PTEN and upregulating the expression level of PD-L1. It is suggested that miR-20a could be used as a biomarker and therapeutic target for the treatment of NSCLC.

Hydrophilic poly((poly(ethylene glycol) methyl ether methacrylate) (P(PEGMA)) brushes were grafted from chloromethylated polyethersulfone (CMPES) hollow fiber membrane surface by surface-initiated atom transfer radical polymerization(SI-ATRP) to improve the membrane’s hydrophilic property. The CMPES hollow fiber membrane was prepared by phase inversion process. The benzyl chloride groups on the CMPES membrane surface could afford effective macroinitiators for grafting the well-defined polymer brushes. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy confirmed the grafting of P (PEGMA) chains. Field emission scanning electron microscopy (FESEM) was used to characterize the surface morphology of the CMPES membrane and modified membrane. The grafting yield of P (PEGMA) was determined by weight gain measurement. The results showed that the number-average molecular weight (Mn) of P (PEGMA) increased with the polymerization time. It was found that the grafting of P (PEGMA) brought higher pure water flux, improved water uptake ratio and better anti-protein absorption ability to CMPES membrane after modification.