Purification of a polysaccharide from Boschniakia rossica and its synergistic antitumor effect combined with 5-Fluorouracil

Current study we purified a polysaccharide (BRP) from Boschniakia rossica and the antitumor effects of BRP alone or combined with 5-Fluorouracil (5-FU) was examined in S180 tumor bearing mice by intragastric administration. The high performance size-exclusion chromatography (HPGEC) analysis showed that BRP was a homogeneous polysaccharide and had a molecular weight of 2.2 × 104 Da. Total carbohydrate content in BRP was determined to be 96.9%, without the presence of protein and nucleic acid. BRP alone or combined with 5-FU could significantly inhibit Sarcoma-180 (S180) tumor growth and increase the spleen index in a dose-dependent manner. Meanwhile a synergistic effect was observed in boosting various immunity functions when the tumor bearing mice receiving BRP plus 5-FU administration, such as stimulating lymphocytes proliferation, increasing NK cell cytotoxicity, enhancing serum interleukin-2 (IL-2) and interferon-gamma (TNF-γ) secretion, as well as augmenting CD4+ and CD8+ spleen T lymphocytes subsets. The results showed that BRP combined with 5-FU presented synergistic effects on antitumor activity in tumor bearing mice. In conclusion, the combination of BRP may boost the suppressed immunity in tumor bearing mice subject to 5-FU chemotherapy, and could serve as a new, promising approach for cancer treatment.