The anti-neoplastic impact of thymoquinone from Nigella sativa on small cell lung cancer : in vitro and in vivo investigations

Abstract

Approximating up to 15% of all lung cancer diagnoses, small cell lung cancer (SCLC) is an aggressive malignancy. With frontline treatment regimen like chemotherapeutics having debilitating side effects, recent decades have seen surging interest in the therapeutic capabilities of medicinal herbs. Nigella sativa, an age-old herb deep-rooted in Middle Eastern and Mediterranean culture and cuisine, has been implicated for its anti-cancer effects. With the pharmacologically active compound of Nigella sativa, thymoquinone (TQ), directing the herb’s curative activities, much research has been published on its anti-cancer effects in various cancers. However, in SCLC, a daunting neoplasm topping the cancer statistics charts in terms of cancer type occurrence and mortality, a single paper in the entire NCBI database exists that touches upon the application of TQ in SCLC. More research and an in-depth one that too, is needed. The current study looks at in vitro activities of TQ in 5 SCLC cell lines, followed by an in vivo study on nude mice xenografts. This thesis commences with TQ’s demonstration to exert cytotoxic effects in all cell lines. TQ was demonstrated to reduce cell viability, induce apoptosis and S phase arrest, and deplete reactive oxygen species. Protein expressions in the concomitant signaling pathways were altered. In addition, TQ exerted tumor suppressive effect in a H446 SCLC xenograft model. To summarize, TQ exhibited anti-cancer impacts on SCLC. The cytotoxic effects were confirmed, along with elucidation of the anti-cancer mechanisms. Future studies could be designed accordingly.

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