CAJ | 학술논문

目的：探讨丙戊酸(VPA)对乳腺癌细胞 MCF7放射敏感性的影响。方法 MCF7细胞用 VPA临床安全剂量0.5 mmol??L-1和临界剂量1 mmol??L-1分别预处理0,24,48和72 h,8Gy 电离辐射后6 h,免疫荧光染色法观察磷酸化组蛋白 H2 AX(γ-H2 AX)焦点形成。对数生长期的 MCF7细胞分别以 VPA 0.5和1 mmol??L-1预处理72 h,4 Gy 电离辐射后48 h,MTT 法检测细胞存活率。 MCF7细胞用 VPA 0.5 mmol??L-1预处理24 h 后,按照每皿接种细胞数分别给予电离辐射2 Gy(每皿500和1000),4 Gy(每皿2000和4000)和6 Gy(每皿8000和16000),计算克隆形成率。 MCF7细胞分别用 VPA 0.5和1 mmol??L-1预处理0,24,48和72 h,流式细胞仪检测细胞周期。结果与正常对照组相比,单独 VPA 0.5 mmol??L-1处理0,24,48和72 h 后,γ-H2 AX 焦点阳性率分别为(5.3±0.6)%,(10.8±1.0)%,(12.6±0.9)%和(17.8±1.1)%( r ＝0.985, P<0.05)；VPA 1 mmol??L-1对γ-H2 AX 焦点形成有相同的影响趋势。单独照射组细胞核内γ-H2 AX焦点阳性率为100%,其中表示 DNA 损伤较重的焦点较大且明亮的 B 类细胞所占比例为(16.5±1.8)%；与单独照射组相比,VPA 0.5 mmol??L-1预处理0,24,48和72 h 后,B 类细胞所占比例分别为(16.5±1.8)%,(28.9±1.0)%,(58.0±2.0)%和(70.8±0.9)%(r＝0.986, P<0.05)；VPA 1 mmol??L-1对辐射诱导的γ-H2 AX焦点形成的影响有相同趋势。 MTT 和细胞克隆形成实验结果显示,与正常对照组相比,单独给予 VPA 0.5 mmol??L-1可显著降低细胞克隆形成率(P<0.05)；与单独照射组相比,VPA 预处理后接受电离辐射能显著降低细胞存活率(P<0.05)和细胞克隆形成率(P<0.05)；VPA 0.5和1 mmol??L-1对细胞周期影响均无统计学差异。结论临床安全剂量和临界剂量 VPA 对肿瘤细胞具有放射增敏作用,且对肿瘤细胞生长具有抑制作用,其机制与增加电离辐射所致的 DNA 双链断裂损伤的蓄积有关。
목적：탐토병무산(VPA)대유선암세포 MCF7방사민감성적영향。방법 MCF7세포용 VPA림상안전제량0.5 mmol??L-1화림계제량1 mmol??L-1분별예처리0,24,48화72 h,8Gy 전리복사후6 h,면역형광염색법관찰린산화조단백 H2 AX(γ-H2 AX)초점형성。대수생장기적 MCF7세포분별이 VPA 0.5화1 mmol??L-1예처리72 h,4 Gy 전리복사후48 h,MTT 법검측세포존활솔。 MCF7세포용 VPA 0.5 mmol??L-1예처리24 h 후,안조매명접충세포수분별급여전리복사2 Gy(매명500화1000),4 Gy(매명2000화4000)화6 Gy(매명8000화16000),계산극륭형성솔。 MCF7세포분별용 VPA 0.5화1 mmol??L-1예처리0,24,48화72 h,류식세포의검측세포주기。결과여정상대조조상비,단독 VPA 0.5 mmol??L-1처리0,24,48화72 h 후,γ-H2 AX 초점양성솔분별위(5.3±0.6)%,(10.8±1.0)%,(12.6±0.9)%화(17.8±1.1)%( r ＝0.985, P<0.05)；VPA 1 mmol??L-1대γ-H2 AX 초점형성유상동적영향추세。단독조사조세포핵내γ-H2 AX초점양성솔위100%,기중표시 DNA 손상교중적초점교대차명량적 B 류세포소점비례위(16.5±1.8)%；여단독조사조상비,VPA 0.5 mmol??L-1예처리0,24,48화72 h 후,B 류세포소점비례분별위(16.5±1.8)%,(28.9±1.0)%,(58.0±2.0)%화(70.8±0.9)%(r＝0.986, P<0.05)；VPA 1 mmol??L-1대복사유도적γ-H2 AX초점형성적영향유상동추세。 MTT 화세포극륭형성실험결과현시,여정상대조조상비,단독급여 VPA 0.5 mmol??L-1가현저강저세포극륭형성솔(P<0.05)；여단독조사조상비,VPA 예처리후접수전리복사능현저강저세포존활솔(P<0.05)화세포극륭형성솔(P<0.05)；VPA 0.5화1 mmol??L-1대세포주기영향균무통계학차이。결론림상안전제량화림계제량 VPA 대종류세포구유방사증민작용,차대종류세포생장구유억제작용,기궤제여증가전리복사소치적 DNA 쌍련단렬손상적축적유관。
OBJECTIVE To study the effect of valproic acid ( VPA) on radiosensitivity to MCF7 breast cancer cells. METHODS MCF7 cells were pretreated with VPA 0.5 and 1 mmol.L-1 for 0, 24, 48 and 72 h respectively, irradiated with 8 Gy lR, and at 6 h post-lR, the γ-H2 AX foci formation in MCF7 cells was tested by immunofluorescence assay. MCF7 cells were pretreated with VPA 0.5 and 1 mmol.L-1 for 72 h, irradiated with 4 Gy lR, and at 48 h post-lR, the cell survival rate was detected by MTT assay. MCF7 cells were pretreated with VPA 0.5 mmol.L-1 for 24 h, and then irradiated according to the amount of cells: 2 Gy (500 and 1000 cells per plate), 4 Gy (2000 and 4000 cells per plate), 6 Gy (8000 and 16000 cells per plate), and the cloning efficiency was calculated. MCF7 cells were pretreated with VPA 0.5 and 1 mmol.L-1 for 0, 24, 48 and 72 h respectively and the cell cycle profile was analyzed via flow cytometry. RESULTS After treatment with VPA alone for 24 h, MCF7 cells showed a significant increase in the amount of γ-H2 AX foci formation ( P < 0. 01). lt was also found that VPA increased lR-induced γ-H2 AX foci formation, which obviously prolonged the pretreatment time of VPA(P<0.01) in a time-dependent manner(r=0.98, P<0.05). VPA 0.5 and 1 mmol.L-1 had the same effect on γ-H2 AX foci formation. Furthermore, VPA was able to cause a significant decrease in lR-induced clonogenic survival but an increase in lR-induced cytotoxicity by MTT assay. Also, VPA alone decreased the plating efficiency of MCF7 cells. However, the cycle profile of MCF7 cells treated with both VPA 0.5 and 1 mmol.L-1 was not changed. CONCLUSION Without affecting the cell cycle profile, both the safe and critical dose of VPA used in clinical epilepsy treatment can significantly increase the accumulation of DNA double strand breaks in the cells and sensitize the cells to lR treatment, suggesting that VPA can induce radio-sensitization of breast cancer cells.