OBJECTIVE  Aimed to examine the effect of Euryale ferox petioles and pedicels polysaccharide (EFPP) on LLC cell allograft model of lung cancer.

  METHODS  Forty male C57BL/6 rats were randomly divided into 4 groups (n=10/group), namely control group, EFPP low dose group (100 mg·kg^-1 EFPP), EFPP high dose group (200 mg·kg^-1 EFPP), 5-Fu(20 mg·kg^-15-Fu). Different doses of EFPP were orally administered once daily for fifteen consecutive days, and the positive drug was injected once every 3 days after the ectopic xenograft tumor model was established. Rats in control group received PBS treatment by gavage. All mice were sacrificed on the second day of the last administration. Tumor samples were taken from each group, and the volume and tumor weight were weighed. Hematoxylin and eosin staining, flow cytometry, TUNEL apoptosis staining and Western blot were used to detect the pharmacodynamics of EFPP.

  RESULTS  The data showed that EFPP could inhibit the proliferation of LLC cells in vivo. In addition, EFPP increased the levels of CD3⁺CD4⁺T, CD3⁺CD8⁺T and CD3^-NK1.1⁺cells. At the same time, EFPP up-regulated the expression of proteins related to the Caspase3 apoptosis pathway.

  CONCLUSION  EFPP can promote LLC cell apoptosis by increasing the infiltration of lymphocyte subsets, up-regulating the expression of cleaved-caspase3 and Bax, and down-regulating the expression of Bcl2. This study provided the scientific basis for the anti-tumor application of EFPP and utilization of euryale ferox stem resources.