Qizhen capsule inhibits colorectal cancer by inducing NAG-1/GDF15 expression that mediated via MAPK/ERK activation.

ETHNOPHARMACOLOGICAL RELEVANCE: Qizhen capsule (QZC) is a traditional Chinese medicine (TCM) preparation that has been widely used in clinical practice and exerts promising therapeutic effects against breast, lung, and gastric cancers. However, studies have not reported whether QZC inhibits colorectal cancer (CRC) development and progression. Meanwhile, the underlying molecular mechanisms of its anticancer activity have not been studied. AIM OF THE STUDY: To investigate the anticancer effects of QZC on CRC and the possible underlying molecular mechanisms of QZC in vitro and in vivo. MATERIALS AND METHODS: The MTT assay and flow cytometry were used to determine the viability and apoptosis of HCT116 and HT-29 cancer cells. A xenograft nude mouse model was used to study the antitumor effects of QZC in vivo. Western blotting was performed to determine the expression of key proteins responsible for the molecular mechanisms elicited by QZC. Immunofluorescence staining was performed to detect the expression of nonsteroidal anti-inflammatory drug (NSAID)-activated gene-1 or growth differentiation factor-15 (NAG-1/GDF15). Small interfering RNAs (siRNAs) were used to silence NAG-1/GDF15 in cells. RESULTS: In this study, QZC significantly reduced the viability of HCT116 and HT-29 cells and induced apoptosis in dose- and time-dependent manners, but displayed much less toxicity toward normal cells. QZC-induced apoptosis in HCT116 cells was accompanied by the deregulation of the expression of the Bcl-2, Bax, PARP, caspase-3, and caspase-9 proteins. Furthermore, QZC induced NAG-1/GDF15 expression in HCT116 cells, while silencing of NAG-1/GDF15 attenuated QZC-induced apoptosis and cell death. Next, QZC increased the phosphorylation of mTOR, AMPK, p38, and MAPK/ERK in HCT116 cells. We then demonstrated that QZC-induced apoptosis and NAG-1/GDF15 upregulation were mediated by MAPK/ERK activation. Moreover, QZC significantly inhibited HCT116 xenograft tumor growth in nude mice, which was accompanied by NAG/GDF15 upregulation and MAPK/ERK activation. QZC also prevented 5-FU-induced weight loss or cachexia in tumor-bearing mice. The expression of Ki67 and PCNA was suppressed, while cleaved caspase-3 level and TUNEL staining were increased in the tumor sections from QZC-treated mice compared to the control. CONCLUSION: QZC is a novel anticancer agent for CRC that targets NAG-1/GDF15 via the MAPK/ERK signaling pathway.

Anticarcinogenic effects of water extract of sporoderm-broken spores of Ganoderma lucidum on colorectal cancer in vitro and in vivo.

Ganoderma lucidum (G. lucidum) polysaccharides (GLPs) have been used as traditional Chinese medicine for cancer prevention for many years. However, the mechanism by which GLP exerts its chemopreventive activities remains elusive. In addition, it is unclear whether sporoderm-broken spores of G. lucidum water extract (BSGLWE), which contains mainly GLPs, has anticancer effects on colorectal cancer. The present study investigated the anticancer effects and potential mechanisms of BSGLWE on colorectal cancer in vivo and in vitro. Our results showed that BSGLWE significantly inhibited colorectal cancer HCT116 cell viability in a time- and dose-dependent manner. Flow cytometry analysis indicated that BSGLWE disrupted cell cycle progression at G2/M phase via downregulation of cyclin B1 and cyclin A2, and upregulation of P21 at mRNA levels. Moreover, BSGLWE induced apoptosis by decreasing Bcl-2 and survivin at mRNA levels, and reduced Bcl-2, PARP, pro-caspase-3 and pro-caspase-9 at protein levels. Furthermore, BSGLWE suppressed tumor growth in vivo by regulating the expression of genes and proteins associated with cell cycle and apoptosis, which was further confirmed by a reduction of Ki67, PCNA, and Bcl-2 expression as determined by immunohistochemistry staining. NSAID activated gene-1 (NAG-1), a pro-apoptotic gene, was significantly upregulated in vivo and in vitro upon BSGLWE treatment at both mRNA and protein levels. In addition, the relative amounts of secreted NAG-1 in cell culture medium or serum of nude mice were all upregulated upon BSGLWE treatments, suggesting a role of NAG-1 in BSGLWE-induced anticolorectal cancer activity. This is the first study to show that BSGLWE inhibits colorectal cancer carcinogenesis through regulating genes responsible for cell proliferation, cell cycle and apoptosis cascades. These findings indicate that BSGLWE possesses chemopreventive potential in colorectal cancer which may serve as a promising anticancer agent for clinical applications.