Knockdown of the M2 Isoform of Pyruvate Kinase (PKM2) with shRNA Enhances the Effect of Docetaxel in Human NSCLC Cell LinesIn Vitro

Abstract

PurposeThe aim of our study was to explore the relationships between the M2 isoform of pyruvate kinase (PKM2) and the sensitivity of human non-small cell lung cancer (NSCLC) cells to docetaxel in vitro.Materials and MethodsWith the method of plasmid transfection, we silenced the expression of PKM2 successfully in A549 and H460 cells. Western blotting and real-time PCR were applied to detect PKM2 expression at protein and gene levels. Cell viability was examined by CCK8 assay. Cell cycle distribution and apoptosis were examined by flow cytometry. P21 and Bax were detected.ResultsExpression of PKM2 mRNA and protein were significantly decreased by shRNA targeting PKM2. Silencing of PKM2 increased docetaxel sensitivity of human NSCLC A549 and H460 cells in a collaborative manner, resulting in strong suppression of cell viability. The results of flow cytometric assays suggested that knockdown of PKM2 or docetaxel treatment, whether used singly or in combination, blocked the cells in the G2/M phase, which is in consistent with the effect of the two on the expression of p21. Cells with PKM2 silencing were more likely to be induced into apoptosis by docetaxel although knockdown of PKM2 alone can't induce apoptosis significantly, which is in consistent with the effect of the two on Bax expression.ConclusionThe results suggest that PKM2 knockdown could serve as a chemosensitizer to docetaxel in non-small lung cancer cells through targeting PKM2, leading to inhibition of cell viability, increase of cell arrest of G2/M phase and apoptosis.

Role of metabolism in cancer cell radioresistance and radiosensitization methods

“…The M2 isoform (PKM2) is a key regulator of glycolysis, expressed only in cancer cells [ 165 ], and targeting this molecule can inhibit cell viability, induce G2/M arrest, and promote apoptosis. Additionally, this can increase the radiosensitivity of NSCLCs and the IR-induced apoptosis and autophagy rates, which are associated with the inhibition of AKT and PDK1 phosphorylation [ 166 ]. PKM2 is targeted by miR-133 as well, and this miRNA is downregulated in radioresistant lung cancer cells.…”

Upregulated expression of pyruvate kinase M2 mRNA predicts poor prognosis in lung adenocarcinoma

“…Moreover, elevated expression of PKM2 is involved in cell proliferation and tumourigenesis, as well as the regulation of immune and inflammatory responses. More importantly, accumulating evidence has suggested that enhanced PKM2 expression correlates with therapeutic resistance in LUAC (Meng et al, 2015;Yuan et al, 2016). Furthermore, selective inhibition or knockdown of PKM2 with RNAi leads to suppression of cell proliferation, induction of apoptosis and increase of the sensitivity of tumor cells to chemotherapy in LUAC, suggesting that selective targeting of PKM2 may serve as a potential therapeutic target for LUAD, especially for patients with chemotherapeutic resistance (Chu et al, 2015;Sun et al, 2015;Suzuki et al, 2019;Wang et al, 2019;Yuan et al, 2016).…”

Metabolic Remodelling: An Accomplice for New Therapeutic Strategies to Fight Lung Cancer

“…In NSCLC, Yuan et al, suggested that PKM2 knockdown could serve as a chemosensitizer to docetaxel, leading to the inhibition of cell viability, cell cycle arrest at G2/M phase and apoptosis [221]. These results further suggest that application of targeting the PKM2 has the potential to be a therapeutic strategy for NSCLC and provides one possible way to improve the chemotherapy effect of docetaxel.…”