To Study The Inhibition Of Proliferation And Metastasis Of The Small Cell Lung Cancer With Transfection Of The Suppressor Gene KAI1 And Treated By ATRA

PART ONEOBJECTIVE TO study the differentiation and proliferation of the Small Cell Lung Cancer that were treated by all-trans-retinoic acid(ATRA). METHODS the cells were treated by ATRA with different concentration. After that,the proliferation and differentiation of NCI-H446 cells were examined by the methods of MTT , the electron microscope,and cytometry analysis.The expression of cornifin protein was tested by IHC, The primers of were designed based on the sequence of gene bank and the express of RARS and RXRS were detected with RT-PCR .RESULT ATRA could obviously inhibit the growth and the differentiation of NCI-H446 cells. When the ATRA concentration were 20μmol/L,10μmol/L,5μmol/L, 2.5μmol/L after 24h, the results of OD were 0.498,0.502,0.503,0.507,0.510. the difference is not significant(P>0.05).the results of OD were0.292, 0.342, 0.467,0.498,0.521 after 48h. the difference is significant(P<0.01) between ATRA20μmol/L group and 5μmol/L group; the results of OD were 0.206,0.312,0.415,0.482,0.509 after 72h, the difference is significant(P<0.05) between ATRA20μmol/L group and 10μmol/L group; the results of OD were 0.189,0.251,0.380,0.487,0.506 after 96h. Therefor the higher ATRA concentration was, the plus the rate of growth inhibition was. ATRA10μmol/L is the best concentration of treatment. The apoptosis of the cells treated by ATRA after 24h,48h,72h were 4.9%, 8.8%, 11.45%; the balance were 4.08%, 4.10%, 4.18%。the difference is significant(P<0.05) after 72h. There were more ATRA-NCI cell arrested in G1/G0 phase. The electron microscope observes that the ATRA cell nuclears diminish, the rates of nuclear/plasma reduce, and the apoptosis cells increase. The expression of cornifin protein decreased in ATRA group, the difference is significant(P<0.05); RT-PCR Electrophoresis graydegree of RARβ and RXRαin ATRA group after 72h treatment were 143.58,78.89; the balance were 105.33,45.37。The positive rate of RARS and RXRS was higher in ATRA cell than non-ATRA cell,the difference is significant (P<0.05).CONCLUSIONS ATRA could inhibit the proliferation and induce differention of the Small Cell Lung Cancer.