Acidic Exo-polysaccharide produced from marine Bacillus sp. NRC5 to treat and protect chemical-induced mammary carcinomas in rats

Abstract Background: Cancer is a leading cause of death worldwide, causing approximately ten million deaths in 2020. This investigation motivated us to study the prophylactic and therapeutic effect of acidic exopolysaccharide obtained from marine Bacillus sp. NRC5 (BEPS) in breast cancer. Methods: The anti-breast cancer efficacy of BEPS was proceeded in female Sprague-Dawley rats in the chemical-induction route. Mammary carcinoma was developed after five months using 7,12-Dimethylebenz-(a)-anthracene (DMBA in a single dose, 65 mg/ kg in an intragastric route). Results: BEPS (200 mg/ kg orally) exhibited remarked protective and therapeutic effect, where it significantly reduced i) cancer growth rate-limiting enzymes; aromatase (51.14 and 77.31%) and Na+/K+ ATPase (78.25 and 73.51%) activities, ii) cyclooxygenase-2 (31.67 and 50.10%) activity, iii) oxidative stress biomarker; malondialdehyde (88.26 and 88.18%) level, iv) estrogen level (51.91 and 60.67%), and carcinoembryonic antigen, CEA (36.7 and 35.14%) compared to DMBA-group that elevated all determined parameters significantly (P≤ 0.05). Conclusion: BEPS showed a promising anti-breast cancer impact with a reasonable safety margin. The result of BEPS may be related to its antioxidant & anti-inflammatory characters and its inhibitory effect on aromatase and Na+/ K+ATPase activities, which is attributed to its unique composition containing sulfated groups and uronic acids.