Aim: This study was designed to investigate the anticancer efficacy of the organic leaf extracts of the plant, Plectranthus vettiveroides (P. vettiveroides), and to analyze the molecular mechanism of the anticancer activity. Methods: The leaf extracts were prepared by polarity-graded serial extraction of the dried leaf powder. The cytotoxic effect of the extracts was analyzed by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The most active ethyl acetate extract was subjected to bioactivity-guided fractionation by column chromatography, which yielded a cytotoxic fraction designated as the P. vettiveroides fraction (PVF). The anticancer property of PVF was confirmed further by clonogenic assay. The mechanism of PVF-induced cell death was analyzed by flow cytometry and fluorescence microscopy. Additionally, the effects of PVF on apoptotic and cell survival pathways were analyzed using western immunoblot analysis. Results: A bioactive fraction PVF, was isolated from the ethyl acetate leaf extract. PVF showed significant anticancer activity against colon cancer cells, whilst normal cells were comparatively less affected. PVF induced strong apoptotic stimuli in colorectal carcinoma cell line HCT116, involving both extrinsic and intrinsic pathways. Investigation into the molecular mechanism of anticancer activity of PVF in HCT116 cells revealed that the fraction activates the pro-apoptotic pathway via tumor suppressor protein 53 (p53) and inhibits the anti-apoptotic pathway by regulating phosphatidylinositol 3-kinase (PI3K) signaling. Conclusions: The findings of this study demonstrate, with mechanism-based evidence, the chemotherapeutic potential of a bioactive fraction PVF, derived from the leaves of the medicinal plant P. vettiveroides against colon cancer.

The review discusses, how the COVID-19 virus evolved to the present form, genome organization and genetic variation of SARS- CoV-2 prevalent globally with special emphasis on Indian strains, a comparison of the first vs. second wave in terms of infectivity and transmission patterns. The population impacted, importance of surveillance, study of genetic variants of COVID-19 virus, development of diagnostics developed in First and second waves of infection and preventive measures like physical means, vaccine administration and treatment strategies using different classes of anti-viral, anti-inflammatory, antibiotic and corticosteroid drugs. The study used the detailed and qualitative online research. The literature studies were conducted to explore the havoc of the COVID-19 Pandemic from the very beginning era to current and future repercussions in worldwide with special context to India. The idea of our work is to be on a high alert and vigilant in the constant studying of the varying characteristics of the pandemic and to produce resources and be able to modify treatment methodologies quickly, if needed, and disseminate our work to the scientific world and community as soon as possible for coordinating a global action to cut off the inevitable future waves of this pandemic. Securing vaccine is the most concern, along with the strategies that could be forward to strengthen the health care system. This paper gives insight by warning the third wave, unless taken utmost care by each individual, national as well international organization could be catastrophic to the entire World.