Jujuboside B inhibits proliferation and induces apoptosis and ferroptosis in colorectal cancer cells with potential involvement of the MAPK signaling pathway

Colorectal cancer (CRC) is one of the most prevalent and life-threatening malignancies worldwide. Jujuboside B (JUB) is a bioactive compound derived from the seeds of <i>Ziziphus jujuba</i>, known for its potential anticancer properties. The present study aimed to investigate the association of JUB with inhibiting the proliferation, apoptosis and ferroptosis of human CRC cells with mitogen-activated protein kinase (MAPK) pathway regulation. First, the human CRC HCT116 cell line was treated with different concentrations of JUB. Subsequently, cell viability was evaluated using MTT assay and colony formation was assessed using a colony formation assay. Flow cytometry was used to detect cell apoptosis and the levels of reactive oxygen species. Western blotting was utilized to assess the expression levels of apoptosis-related proteins, ferroptosis regulators and MAPK pathway-related proteins. In addition, biochemical assay kits were used to evaluate the levels of malondialdehyde, glutathione, total iron and ferrous iron. The results demonstrated that cell viability and colony formation were markedly decreased after JUB treatment, whilst the level of apoptosis was notably increased in a concentration-dependent manner. Using electron microscopy, cells treated with JUB exhibited typical apoptotic bodies, as well as mitochondrial swelling and cristae disruption, further demonstrating JUB-induced cell apoptosis. Western blot analysis indicated that JUB treatment markedly reduced the expression of B-cell lymphoma-2 (Bcl-2) but notably increased the expression of Bcl-2 associated X-protein and cleaved caspase-3. Additionally, JUB induced ferroptosis and inhibited the MAPK signaling pathway in CRC cells. Collectively, the findings of the present study suggest that JUB has the potential to inhibit CRC cell proliferation and induce apoptosis through regulating the MAPK pathway. Therefore, JUB may be a promising therapeutic agent for the treatment of CRC.