Tanshinone IIA inhibits cell growth by suppressing SIX1-induced aerobic glycolysis in non-small cell lung cancer cells.

Aerobic glycolysis plays a key role in cancer cell metabolism and contributes to tumorigenesis, including that of non-small cell lung cancer (NSCLC). Tanshinone IIA (Tan IIA), an active compound of Salvia miltiorrhiza, exhibits antitumor properties. Multiple mechanisms are involved in the antitumor action of Tan IIA in lung cancer, such as inhibiting cell growth, promoting cell apoptosis and influencing cellular metabolism. However, the effects of Tan IIA on NSCLC cells and its mechanisms of action remain unclear. The present study shows Tan IIA dose-dependently attenuated the growth of NSCLC cells and in vitro in a dose-dependent manner. Moreover, Tan IIA markedly decreased the ATP level, glucose uptake and lactate production in the NSCLC cells in vitro. Tan IIA also inhibited tumor growth in a xenograft model in vivo. Mechanically, Tan IIA treatment decreased sine oculis homeobox homolog 1 (SIX1) mRNA and protein levels, thus leading to the downregulation of pyruvate kinase isozyme M2, hexokinase 2 and lactate dehydrogenase A (LDHA) expression in A549 cells. SIX1 knockdown with small interfering-RNA inhibited glycolysis in NSCLC cells, suggesting that SIX1 plays a role in the antitumor effect of Tan IIA on NSCLC cells. More importantly, it was demonstrated that SIX1 expression was stimulated in patients with NSCLC and was positively correlated with the LDH serum level. Finally, SIX1 low expression levels predicted the poor prognosis of patients with NSCLC. In conclusion, the present study showed that Tan IIA functioned as an anti-glycolysis agent in NSCLC cells by downregulating SIX1 expression and inhibiting cell proliferation.

Curcumin ameliorates H2O2-induced inflammatory response in chondrocytes by inducing autophagy activation.

Relapsing polychondritis (RP) is a clinical disease characterized by inflammation of cartilage tissue and chondrocytes. The principal curcuminoid curcumin is the most active component in turmeric and has been reported to have a chondroprotective effect, including anti-inflammatory activity, which is vitally important for mitigating RP symptoms and prognosis. However, the mechanisms underlying these actions have remained to be fully elucidated. In the present study, the chondroprotective mechanisms of curcumin on hydrogen peroxide (H2O2)-treated primary chondrocytes were examined in vitro. The viability of chondrocytes treated with H2O2 was significantly reduced in a dose- and time-dependent manner. Cotreatment of curcumin with H2O2 significantly decreased growth inhibition. It was observed that curcumin inhibited the expression levels of the inflammatory mediators interleukin (IL)-1ß, IL-6 and inducible nitric oxide synthase and induced autophagy activation. Curcumin increased the protein levels of the autophagy marker beclin-1 and light chain 3-II and decreased the expression levels of P62 in H2O2-treated chondrocytes. The curcumin-induced anti-inflammatory effects were markedly abrogated by the autophagy inhibitor 3-methyladenine. In conclusion, the present study suggested that curcumin regulates inflammatory factors by activating autophagy in chondrocytes. The protective role of curcumin in chondrocytes was demonstrated, suggesting that it should be explored for the prophylactic treatment of RP in the clinic in the future.