Aqueous extract of Solanum nigrum inhibit growth of cervical carcinoma (U14) via modulating immune response of tumor bearing mice and inducing apoptosis of tumor cells

To explore the antitumor activity of aqueous extract of Solanum nigrum (SNL-AE) and its possible inechanism, we examined the effects of SNL-AE on the tumor growth in vivo, the number of CD4+, CD8+ T lymphocyte subsets of peripheral blood in tumor-bearing mice by means of FACScan flow cytometer, the expression of PCNA in U14 cervical carcinoma section by means of immunohistochemistry SP method, the cell cycle of transplanted tumor by means of FACScan flow cytometer and DNA fragmentation by means of agarose gel electrophoresis. Our results showed that SNL-AE could inhibit U14 cervical carcinoma growth and increased the number of CD4+ T lymphocyte subsets as well as the ratio of CD4+/CD8+ T lymphocyte, decreased the number of CD8+ T lymphocyte subsets of tumor-bearing mice and PCNA positive cells. Furthermore, it had the abilities to cause cell cycle arrest in G0/G1 phase and to induce apoptosis of more transplanted tumor cells in a dose-dependent manner. These results indicated that SNL-AE could suppress the cervical carcinoma via modulating immune response of the tumor-bearing mice and causing tumor cell cycle at-rest in G0/G1 phase, as well as inducing apoptosis with little toxicity to the animals. (C) 2009 Elsevier B.V. All rights reserved.