Studies Of The Effects Of The Tachyplesin On The Human Lung Adenocarcinoma SPC-A-1 Cells

In the study, we used the tachyplesin which is isolated and purified from the acidextracts of horseshoe crab (Tachypleus tridematus) hemocytes, to treat the human lung adenocarcinoma SPC-A-l cells and the human normal diploid cell line WI-38 , and investigated the biological effects of tachyplesin on SPC-A-l cells and functional characteristics, and fuither study the ftinctional mechanism of tachyplesin on SW-A-I cells.The results showed that the proliferation of SPC-A-l cells were effectively inhibited after being treated x~ith 6.0 ~i g/ml tachyplesin, the rate of cell growth inhibitory was 78.64%, the mitotic index decreased to 27%~, the cell cycle was apparently changed . With flow cytometxy , it has been found that G&G1 phase markedly increased, whereas S and G2+M phases decreased . The results showed that SPC-A-l cells had undergone restorationally morphological changes which were similar to homologously normal diploid cell after being treated by opotical microscope observation, the volume of cells increased and the morphology tended to be consistent, the nucleo-cytoplasmic ratio decreased. It also showed that microvill and filopodia of cell surface reduced while sheed pseudopodia increased ; the volume of nuclear decreased and the shape became regular , the number and volume of nucleolus decreased , heterochromatin decreased whereas euchromatin increased by scanning electron microscope and transmission electron microscope observation; In the cytoplasm, the number of mitochondrion increased and the structure became consistent, Golgi complex turned to be relatively typical, endoplasmic reticulum increased and polyribosome decreased , but the morphology and ultrastructure of human normal diploid cell line Wl-38 had not been apparently changed after being treated ; It has also showed that the activity of AKPase was apparently decreased and the distribution was changed by cytochemical observation. In addition, the immunocytocheinical assay revealed that the expression of CEA decreased in SPC-A-l cells surface , the expression activities of proto-oncogene which included c-erbB-2,2c-myc, NF- K B, PCNA and tumor suppressor genes which included p53, p21 , Rb, p16 related with cell proliferation and differentiation were differently regulated after being treated with tachyplesin . Furthennore, tachyplesin had the abilities to markedly decrease the expression of CDK4 and Cyclin Dl which played a important role in the cell cycle control On the other hand, the expression of CEA, c-erbB-2 , p53 and c-myc genes in Wl-38 cells had not apparently changed after being treated with tachyplesin.These results showed that tachyplesin could not only effectively inhibit the proliferation of human lung adenocarcinoma SPC-A-l cells , but reverse malignant phenotypes of SPC-A-1 cells from the biological , cell cycle dynamical and morphological levels , and could regulated and intervened the expression of the genes related with the cell cycle contol , but had no effects on the morphology , ultrastructure and the expression of some genes of human embryonic diploid lung fibroblast WI-38 cells It could be concluded that tachylesin has the induced-differentiation effects on the human lung adenocacinoma SPC-A-l cells.