Radiosensitization Effects Of 4-HPR,C-DDP On Cervical Carcinoma Cell Line HeLa

OBJECTIVE: N-4-hydroxyphenyl retinode (4-HPR) is a syntheticamide analogue of all trans retinoic acid (ATRA). It was indicated that4-HPR could inhibit the growth, promote the apotosis of HeLa in lots ofin vitro experiments; Some clinical researches discovered that 4-HPRcould prevent the recurrence of some kinds of tumor. Cis-platinum(C-DDP) commonly used in cervical cancer chemotherapy, which couldenhance the sensitivity of radiotherapy on a lot of turner cell. But theadverse reaction and its drug resistance limit its clinical application. Thepurposes of this study are:1,To investigate the growth suppression andapoptosis inducing effect of N-4-hydroxyphenyl retinode (4-HPR) onhuman Hela cell lines; 2,And to investigate the influence of the apoptosisrate and changes in cell cycle of HeLa cells treated with 4-HPR, C-DDP,or/andγ-ray.METHODS: 1, MTT assay was employed to examine theproliferation Effects of 4-HPR ,C-DDP and radiation on HeLa bydifferent time and different concentration. 2, TEM was used to observethe ultrastructural change of HeLa cells treated with 4-HPR ,C-DDP andγ-ray. 3,The apoptosis rate and change in cell cycle of HeLa cells treated with 4-HPR ,C-DDP or/andγ-ray were examined by flow cytometer.RESULTS: 4-HPR ,C-DDP andγ-ray both could induce pristineapoptosis of Hela cells as monotherapy or in combination; while therearen't significant difference between apoptosis rate of simple use of4-HPR ( 1μmol.L^-1 , C-DDP and apoptosis rate of control group(p＞0.05), while the difference are significant when the concentration of4-HPR are 2μmol.L^-1, 4μmol.L^-1 (p＜0.01) and simply useγ-rayCombined use of 4-HPR (2μmol.L^-1, 4μmol.L^-1 and C-DDP orγ-raycould increase the apoptosis rate significantly. It is significantly differentbetween the apoptosis rates of each concentration of 4-HPR+C-DDP+γ-ray and C-DDP+γ-ray .There is no statistical difference between theinfluences of cell circle of each group.CONCLUSION: 1.4-HPR ,C-DDP can inhibit the growth of HeLacells, and the inhibition is time and concentration dependent ; 2.4-HPR ,C-DDP andγ-ray can induce apoptosis of HeLa ; 3. Low dose4-HPR, C-DDP can enhance the sensitivity of radiotherapy., combineduse 4-HPR, C-DDP andγ-ray can increase the apoptosis rate of HeLaevidently; 4. 4-HPR, C-DDP, or/and radiation can induce the changes ofthe generation cycle.