Fisetin Deters Cell Proliferation, Induces Apoptosis, Alleviates Oxidative Stress and Inflammation in Human Cancer Cells, HeLa

Background: Fisetin, a flavonol profusely found in vegetables and fruits, exhibited a myriad of properties in preclinical studies to impede cancer growth. Purpose: This study was proposed to delineate molecular mechanisms through analysing the modulated expression of various molecular targets in HeLa cells involved in proliferation, apoptosis and inflammation. Methods: MTT assay, flow cytometry, nuclear morphology, DNA fragmentation and Annexin–Pi were performed to evaluate the anti-cancer potential of fisetin. Furthermore, qPCR and proteome profiler were performed to analyse the expression of variety of gene related to cell death, cell proliferation, oxidative stress and inflammation and cancer pathways. Results: Fisetin demonstrated apoptotic inducing ability in HeLa cells, which was quite evident through nuclear morphology, DNA ladder pattern, decreased TMRE fluorescent intensity, cell cycle arrest at G₂ /M and increased early and late apoptosis. Furthermore, fisetin treatment modulated pro-apoptotic genes such as APAF1, Bad, Bax, Bid and BIK at both transcript and protein levels and anti-apoptotic gene Bcl-2, BIRC8, MCL-1, XIAP/BIRC4, Livin/BIRC7, clap-2/BIRC3, etc. at protein levels to mitigate cell proliferation and induce apoptosis. Interestingly, the aforementioned alterations consequently led to an elevated level of Caspase-3, Caspase-8 and Caspase-9, which was found to be consistent with the transcript and protein level expression. Moreover, fisetin downregulated the expression of AKT and MAPK pathways to avert proliferation and enhance apoptosis of cancer cells. Fisetin treatment also improves oxidative stress and alleviates inflammation by regulating JAK-STAT/NF-kB pathways. Conclusion: Together, these studies established that fisetin deters human cervical cancer cell proliferation, enhances apoptosis and ameliorates inflammation through regulating various signalling pathways that may be used as a therapeutic regime for better cancer management.