Colorectal cancer (CRC) is the third‐most common cancer around the world, accounting for approximately 10% of cancer‐related mortality. Deeper molecular understanding of colorectal carcinogenesis will provide evidences for identification of early diagnostic indicators and novel therapeutic strategies for CRC treatment. The p21cdc42/rac1‐activated kinase 5 (PAK5) has been reported to be involved in a variety of tumor‐promoting behaviors, whereas the underlying mechanisms of PAK5 in CRC progression are still obscure. Our current study revealed an upregulated expression of PAK5 in human CRC tissues as compared with normal adjacent biopsies, which was associated with tumor progression and metastasis. We further unraveled that inhibition of PAK5 was correlated with restrained proliferation, migration, and invasion of CRC cells in vitro and in vivo. Moreover, we showed an indispensable role of PAK5 in interacting with Cdc42 and Integrin β1, β3, thus, to facilitate the migration and invasion of CRC cells. Collectively, we pointed out a potential of PAK5 to serve as a novel therapeutic target in restricting CRC proliferation and metastasis. The uncovered mechanisms will deepen the comprehension with regard to the mechanisms of CRC progression, as well as providing new insights for therapeutic intervention in colorectal cancer.

Tubeimoside I (TBMS) is a natural compound with antitumor properties. However, the detailed mechanism underlying the function of TBMS in liver cancer has not been fully elucidated. In the present study, TBMS was shown to suppress cell proliferation and induce S phase cell cycle arrest in HepG2 cells. Furthermore, TBMS treatment induced autophagy, evidenced by autophagosome accumulation, and increased the mRNA expression of Beclin 1 and microtubule-associated protein 1 light chain 3 (LC3)-I. However, flow cytometry analysis demonstrated that TBMS exerted no effect on cell apoptosis. Moreover, TBMS increased the phosphorylation of AMP-activated protein kinase (AMPK) in a concentration-dependent manner, thereby activating the AMPK signaling pathway. A specific AMPK inhibitor, compound C (CC), caused markedly suppressed TBMS-induced accumulation of LC3-II. In addition, the mRNA expression of LC3-Ι and Beclin 1 was also suppressed in cells treated with TBMS and CC in combination. The results of the present study provide new insights into the role of TBMS in inducing autophagy and support the potential application of TBMS for liver cancer treatment in the clinical setting.