Studies Of Paclitaxel On Morphology Of Apoptosis And Effect Of Antioxide Function Of Canine Breast Tumor Cell In Vitro Culture

Apoptosis which occurred in all the tumor tissues was closely related to the occurrence, development and metastasis of tumor. Chemotherapeutic drug achieved the therapeutic effect mainly by inducing apoptosis of cancer cells. Therefore, inducing apoptosis of tumor cells became a hotspot for tumor treatment research. Natural medicines which had extensive selectivity, little toxic side effect and low drug resistance were important tendency of studying on anti-tumor with Chinese medicines. Paclitaxel was a new natural broad-spectrum anti-tumor drug, by which the mechanism of apoptosis induced was to lead to cell cycle arrest in G2/M phase mainly by restraining mitosis of cells, thus the normal mitosis of cells and cell multiplication were interrupted. Canine breast tumor was a kind of tumor disease which was clinically common for veterinary. The study of effect on canine breast tumor with paclitaxel hasn't been reported yet Home and Abroad, and dog had a close relation with human, also there was similar aspect in environment and cause of cancer between dog and human, so dogs were used as tumor model and studied., the mechanism of anti-cancer of animal tumor cells induced by paclitaxel was approached, which played a very important role in treating animal tumor and treatment scheme for human cancer.This subject took the Canine breast tumor cells lines CHMm strain cultured in vitro as a model. The CHMm was treated with different concentrations of paclitaxel, cell multiplication, cytotoxic effect, change of cell morphology and antioxygen function factor such as SOD, CAT, MDA were detected at 24h, 48h and 72h after cultured, the treatment time-concentration effect relationship was analyzed and the change of cell morphology and Oxy-free Radicals of apoptosis induced by paclitaxel were approached, which could provide more reliable experimental data for further study on the mechanism of apoptosis of canine breast tumor cells induced by paclitaxel as well as the clinical application of paclitaxel for the treatment of cancer. The experimental result indicated that:1. Change of canine breast tumor cells growth effected by Pacilitaxel with MTT chromatometry and trypan blue exclusion experiments was detected ,The results indicated inhibition radio gradually increased with increase of paclitaxel concentration and culture time, but cells activity decreased gradually, which was in time-dose dependent manner; By detecting the lactic acid dehydrogenase (LDH) activity, the result showed that there were significant difference between paclitaxel groups with different concentrations at the same tim(eP<0.01), There were no significant differences among 1μmol/L paclitaxel group at 24h, 0.1μmol/L paclitaxel group at 48h and 0.01μmol/L paclitaxel group at 72h at different time(P>0.05), other groups had significant difference compared with each othe(rP<0.01), which indicated that paclitaxel could destroy the cell membrane integrity, affected DNA and RNA synthesis and increased LDH leakage rate of canine breast tumor cells, and the LDH activity increased, exerting cytotoxic effect, which was in time-concentration dependent manner.2. Observing the growth of canine breast tumor cells under reverse microscope; morphological change of apoptosis of canine breast tumor cells was observed with AO/EB double fluorescence staining dyeing under fluorescent microscope and transmission electron microscope. Marked cells in control group integrity, with cells distribution even, more nuclei in a cell, nuclei large and prominent, plenty of microvillus and endoplasmic reticulum, chromatin distribution even; In experimental group, cytoplasm condensation, chromatin condensation, with microvillus on the surface of cell membrane disappearance, much vacuolar degeneration in cytoplasm, apoptotic body formation, mitochondrial membrane incompleteness and swelling. The result indicated that paclitaxel could induce the apoptosis of canine breast tumor cells, and apoptosis aggravated with time and increase of drug concentration.3. Different concentrations of paclitaxel effected on the Canine breast tumor cells at different time was marked as follows: MDA content gradually increased in cells, there was significant difference between control group and each experimental group (P<0.01); SOD activity decreased and the change of CAT activity was similar to the change of SOD, which was in time-concentration dependent manner.