Effect Of HCPT, PYM Or Their Combination On The Growth And Telomerase's Activity Of Tca8113 Cell Line

The incidence of carcinama of the tongue is about 0.6/105 ,and it is the No.1 in all kinds of tumors in oral cavity. Most of the carcinomas of the tongue can transfer to lymph nodes, and the proportion can reach to 60%-80%. In the late period, the metastasis to distant tissue may happen. Generally, synthetic therapies is adopted to treat patients, obviously chemical therapy has a unsubstituded effect in all these therapies. Hydorxycamptothecin is an alkaloid that is distilled from a special kind of tree's root, skin and fruit. This kind of trees is unique in our country and belongs to Gongtong subject. HCPT directly destroy DNA and inhibit the synthesis of DNA. It is a drug that has peculiar effect on special cell's cycle, especially S period, and has the effect of hindering the G2/M border.Adopting MTT assay.clonogenic assay.flow cytometry, morphologic observation,telomeric repeat amplification protocol (TRAP) and so on.the research study the inhibiting effect on carcinama of the tongue's Tca8113 cell groeth and telomerase's activity by using single or associated HCPT and Pingyangmycin (PYM).the experiment's results is as followed:1.Adopting MTT assay to research the inhibiting effect of HCPT.PYM and4Cisplatin(DDP),by applying one or two of them.the result is that HCPT has obviously inhibiting effect on Tca8113's growth.especially associated with PYM.Applying.single or both of them 96 hours.the best IC30 is PYM 416ng/ml,HCPT 109ng/ml,PYM+HCPT (100+35ng/ml) respectively.The numbers of relative antitumor activity are 2,12 and (60+39) respectively.2.Applying single or both HCPT and PYM's IC30 to the Tca8113,we find that (1) the speed of growth become slow.population doubling time prolong ;(2)the clonogenecity drop;(3)the cell's cycle of HCPT group and associated group change greatly.the proportion of S,G2 period cell increase;(4)the shape and ultrastructure of cell have obviously changed.the number of megakaryocyte and polynuclear cells increase.vacuolar degeneratine increase, retrograde degeneration occur; (5) telomerase's activity drop.Supplying HCPT's ICso to Tca8113 cells 24h,48h,72h and 96h, we find cell's telomerase's activity begin to drop dramatically after 48h,and the result represent that its effect has dependency on concentration and dose to some extent.The upper results represent that:HCPT has a good inhibiting activity to Tca8113 cell strain.especially applied with PYM.HCPT and PYM can drop the telomerase's activity.so this may be one of their inhibiting carcinoma effect targets.Summarizing into a word, HCPT may have a good expectation in clinic;deeper exploration in telomerase make understanding the resistance to carcinoma's theory of drugs used in chemical therapy easier.developing new drugs that inhibit telomerase's activity and developing new inspecting method that is sensible to chemical therapy are needed.