Biogenic selenium nanoparticles encapsulated Lactobacillus probiotics targeting colon tumorigenesis: A promising drug delivery system

Selenium nanoparticles are less toxic compared to other selenium forms, and their biogenic production leads to improve bioavailability. However, Lactobacillus probiotics previously exhibited anticancer activity. The current study was evaluated to investigate the therapeutic potential of biogenic selenium nanoparticles that was synthesized via Lactbacillus plantarum ( L. plantarum) and Lactbacillus casei ( L. casei) against colorectal cancer. The induction of colorectal cancer was carried out via a single dose (5 mg/kg) of 3-methyl-1, 2-dyhydrobenzo(j)aceanthrylene [3-MBA]. After that, animals were treated using 200 µl (from stock concentration 1.0 × 10 9 CFUs per ml) of selenium nanoparticles derived from L. casei (SeNPs-Ca) or selenium nanoparticles derived from L. plantarum (SeNPs-P) as two separate treated groups for two weeks. Colorectal tumor induction declared a significant increment in total antioxidant capacity. Meanwhile, malondialdehyde level decreased upon 3-MBA intoxication. Molecular analysis of Beclin1 as an autophagy signaling pathway revealed a remarkable reduction upon 3-MBA intoxication. Meanwhile, a significant overexpression was declared in both EGFR and MMP-9 genes post 3-MBA-induced colorectal tumor. Furthermore, a remarkable alteration was recorded in the protein expression of both p53 and TNF-α post 3-MBA injection. Both two treated groups of biogenic selenium nanoparticles declared a significant improvement in the measured parameters, with the superiority of SeNPs-Ca in modulating the altered biomarkers. Histopathological examination of colon tissue confirmed the obtained results. In conclusion, biogenic selenium nanoparticles derived from Lactobacillus probiotics could be a promising candidate as a safe and effective antitumor agent in colorectal tumor therapy and could be a promising drug delivery system targeting tumors.