CRC (colorectal cancer) is one of the most malignant tumours in both developing and developed countries. It is estimated that 60% of CRC patients have liver metastasis. In the present study, we show that miR-30b is an important regulator in human CRC migration and invasion, which are vital steps in CRC liver metastasis. miR-30b was significantly down-regulated in primary CRC specimens compared with normal tissues. Furthermore, miR-30b was much lower in liver metastasis tissues than in CRCs. We validated SIX1 (SIX homeobox 1), a member of the SIX homeodomain family of transcription factors and an EMT (epithelial-mesenchymal transition)-promoting gene, as the direct target of miR-30b. Forced expression of miR-30b inhibited CRC cell migration and invasion in vitro via its target gene SIX1. Furthermore, an inverse correlation between expression of SIX1 and miR-30b has been observed both in primary CRC specimens and liver metastasis. Taken together, miR-30b plays an important role in mediating metastatic related behaviour in CRC. miR-30b may serve as a potential diagnostic marker and therapeutic target for patients with CRC in the future.

Previous studies have indicated that high expression of lactate dehydrogenase A (LDHA) exists in many human cancers. Recently, several reports showed that silencing or inhibition of LDHA could suppress metastasis of human cancer including renal cell carcinoma (RCC). However, the mechanism remains unknown. The role of LDHA in RCC migration and invasion was investigated using immunohistochemistry, western blotting, Transwell and scratch assays, and in vivo experiment. The influence of LDHA on the Warburg effect was also investigated by LDHA activity and lactate production assay. LDHA was overexpressed in RCC tissues and predicted a worse survival following renal resection. Correlation analysis demonstrated that LDHA was negatively correlated with E‑cadherin and positively with N‑cadherin. Experimentally, both in vivo and in vitro experiments found downregulation of LDHA suppressed RCC cells migration and invasion by inhibiting EMT. In addition, results indicated LDHA could promote the Warburg effect. Further research presented that the LDHA inhibitor, oxamate, suppressed tumor metastasis by inhibiting LDHA activity and EMT. These results demonstrated that LDHA mediates tumor metastasis by promoting EMT in RCC, suggesting that LDHA could be a promising therapeutic target for RCC therapy.

Recent studies have found that propofol may protect brain from cerebral ischemic-reperfusion injury. However, the underlying mechanism remains unclear. The effects of propofol were evaluated in HBVSMC after hypoxia/reoxygenation (H/R). Cell viability and levels of SOD, LDH, and MDA were measured. Apoptosis was detected by flow cytometry. The levels of Bax, Bcl-2, Caspase3, Sur2b, Kir6.1, JNK, p-JNK, mTOR, and p-mTOR proteins were measured by western blotting. H/R decreased cell viability and SOD activity and increased LDH leakage and MDA content in HBVSMC, all of which were significantly reversed by propofol. Propofol suppressed the levels of H/R-induced apoptosis. The expression of Bcl-2 and p-mTOR was significantly downregulated and the expression levels of Bax, Caspase3, Kir6.1, and p-JNK were upregulated following H/R injury. The ratio of p-JNK/JNK was increased; however, that of p-mTOR/mTOR decreased correspondingly. The effects on the expression of these proteins were reversed by propofol treatment. SP600125 enhanced and Everolimus attenuated the effect of propofol. These findings suggested that the protective effect of propofol against H/R injury in the HBVSMC was through the inhibition of apoptosis by inducing the expression of Bcl-2 and p-mTOR as well as inhibiting the expression levels of Bax, Caspase3, Kir6.1, and p-JNK.