Mangosteen Inhibits Growth and Survival of Cervical Cancer Cells.

BACKGROUND: Cervical cancer is the most common cancer of the female reproductive system. Late-stage cervical cancer treatment has been largely unsuccessful, and urgent anti-cancer therapy is needed. Mangosteen, a tropical fruit, has been studied and found to be rich in xanthones, known anti-cancer compounds. This study was designed to investigate the effect of mangosteen extract (ME) on SiHa cervical cancer cells and to explore the underlying molecular mechanisms. MATERIALS AND METHODS: Clonogenic survival assay, Quick Cell Proliferation Assay, terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) staining, and caspase-3 activity kits were used to investigate the in vitro role of ME treatment in SiHa cervical cancer cell growth. We further investigated the possible molecular mechanisms using RT-PCR. Statistical analysis was done with unpaired two-tailed Student's t-test and significance at p-value <0.05; each experiment was repeated three times. RESULTS: Our study found that the growth and proliferation of SiHa cervical cancer cells was inhibited by ME. ME also induced apoptosis in SiHa cervical cancer cells. The anti-proliferative effect of ME on cervical cancer cells was associated with statistically significant (p<0.05) down-regulation of the pro-proliferative molecules cyclin B, cyclin D and cyclin E. The pro-apoptotic effect of ME was associated with statistically significant (p<0.05) down-regulation of the anti-apoptotic molecules flice-like inhibitory protein (FLIP) and survivin. CONCLUSION: ME impedes the growth and survival of SiHa cervical cancer cells by down-regulating cyclin B, cyclin D, cyclin E as well as FLIP and survivin. ME may be a promising strategy for targeted cancer immunotherapy development.

SARS-CoV-2 spike protein inhibits growth of prostate cancer: a potential role of the COVID-19 vaccine killing two birds with one stone.

To investigate the effects of isolated SARS-CoV-2 spike protein on prostate cancer cell survival. The effects of SARS-CoV-2 spike protein on LNCaP prostate cancer cell survival were assessed using clonogenic cell survival assay, quick cell proliferation assay, and caspase-3 activity kits. RT-PCR and immunohistochemistry were performed to investigate underlying molecular mechanisms. SARS-CoV-2 spike protein was found to inhibit prostate cancer cell proliferation as well as promote apoptosis. Further investigation revealed that anti-proliferative effects were associated with downregulation of the pro-proliferative molecule cyclin-dependent kinase 4 (CDK4). The increased rate of apoptosis was associated with the upregulation of pro-apoptotic molecule Fas ligand (FasL). SARS-CoV-2 spike protein inhibits the growth of LNCaP prostate cancer cells in vitro by a two-pronged approach of downregulating the expression of CDK4 and upregulating FasL. The introduction of SARS-CoV-2 spike protein into the body via COVID-19 vaccination may have the potential to inhibit prostate cancer in patients. This potential beneficial association between COVID-19 vaccines and prostate cancer inhibition will require more extensive studies before any conclusions can be drawn about any in vivo effects in a human model.