Epidermal growth factor receptor (EGFR) pathway is overexpressed in head and neck cancer (HNC). Lupeol, a natural triterpene (phytosterol found in fruits, vegetables, etc.), has been reported to be effective against multiple cancer indications. Here we investigate the antitumor effects of Lupeol and underlying mechanism in oral cancer. Lupeol-induced antitumor response was evaluated in two oral squamous cell carcinoma (OSCC) cell lines (UPCI:SCC131 and UPCI:SCC084) by viability (MTT), proliferation, and colony formation assays. Lupeol-mediated induction of apoptosis was examined by caspase 3/7 assay and flow cytometry. Effect of Lupeol on EGFR in the presence or absence of EGF was delineated by Western blot. The mRNA stability assay was performed to check the role of Lupeol on COX-2 mRNA regulation. Lupeol inhibited proliferation of OSCC cells in vitro by inducing apoptosis 48 h post treatment. Ligand-induced phosphorylation of EGFR and subsequent activation of its downstream molecules such as protein kinase B (PKB or AKT), I kappa B (IκB), and nuclear factor kappa B (NF-κB) was also found to be, in part, suppressed. Interestingly, Lupeol suppressed expression of COX-2 at mRNA and protein level in a time-dependent manner. Primary explants from oral squamous cell carcinoma tissues further confirmed significant inhibition of proliferation (Ki67) in Lupeol-treated explants as compared to untreated control at 48 h. Together these data suggest that Lupeol may act as a potent inhibitor of the EGFR signaling in OSCC and therefore imply its role in triggering antitumor efficacy.

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Nowadays, exposure to heavy metals and their detrimental effects in humans are grave health concerns. In this study, we investigated the protective effect of resveratrol (RES) against CdCl2 (cadmium chloride)-induced impairment of spermatogenesis, histopathological alterations, and the up-regulation of epidermal growth factor receptor (EGFR) signaling cascade in Swiss albino mice. Two different doses of CdCl2 were injected intraperitoneally into two groups of mice, and in the third group RES was administered orally before injecting CdCl2 (3 times/wk) for 14 days. Sperm motility, count, vitality, and morphology were analyzed. Hematoxylin and eosin (H&E) staining, immunohistochemistry (IHC), and western blot analyses were performed on testis tissue. In CdCl2-administered animals, significant perturbations of spermatogenesis and histoarchitecture of seminiferous tubules were observed. p-EGFR, p-AKT, AKT1/2/3, NF-κβ (p50), and COX-2 of the EGFR cascade were up-regulated. Although there was significant negative correlation between percentage of motile cells and protein expression, we found positive correlation between morphologically abnormal cells and overexpression of proteins in CdCl2-only treated groups. Marked improvement of sperm parameters and histopathological damages as well as down-regulation of the EGFR signaling cascade were observed in the RES-pretreated mice. Hence, the present study elucidates that RES protects against CdCl2-induced perturbation of spermatogenesis and overexpression of EGFR and its downstream signaling proteins.