ABSTRACT
The tadpole extract without large molecular protein(T-871) was prepared from dry tadpoles. This extract and RPMI1640 medium were mixed in the ratio of 1:50(V/V) to form T-871 medium. HeLa cells were cultured in the T-871 medium in order to study the possible mechanism of HeLa cell differentiation induced by tadpole extract. We found that there was a decreased acitivity of LDH which may be released through HeLa cell membrane in the 2 day's cultured T-871 medium. After 3 day's culture in the T-871 medium we found that on the HeLa cell membranes, Na-K-ATPase activity reduced and the content of Con A receptors increased. When these cells were analyzed by flow cytometry(FACS-420), the results indicated that HeLa cells accumulated in G_2 and M phases of the cell cycle and the influence on DNA and RNA content of the HeLa cells was insignificant. HeLa cells cultured by RPMI 1640 medium or T-871 medium for 3 days were inoculated into the dorsal hypodermis of 12 nude mice, respectively. Then after 24 hours this extract was injected to each nude mouse at dose of 0.3 ml each day. Our study showed that T-871 could result in decrease of tumor formation such as delay of tumor nodule appearance and reduce of tumor weight. This study suggested that the changes of the cell membrane may be caused by the tadpole extract. It may also reduce malignancy of the HeLa cells.