Apoptosis-inducing effect of 131I-K237 on human prostate cancer LNCaP cells
10.3760/cma.j.issn.2095-2848.2014.06.014
- VernacularTitle:131I-K237对人前列腺癌LNCaP细胞的凋亡诱导作用
- Author:
Juan LI
;
Yu ZHANG
;
Qian ZHAO
;
Jun GUO
- Publication Type:Journal Article
- Keywords:
Prostatic neoplasms;
Tumor cells,cultured;
Iodine radioisotopes;
Apoptosis
- From:
Chinese Journal of Nuclear Medicine and Molecular Imaging
2014;34(6):480-483
- CountryChina
- Language:Chinese
-
Abstract:
Objective To assess the in vitro affinity and apoptosis-inducing effect of 131I-K237 peptide (H-His-Thr-Met-Tyr-Tyr-His-His-Tyr-Gln-His-His-Leu-OH) to LNCaP prostate cancer cell line.Methods The K237 peptide was radiolabeled with 131I by the Iodogen method.The radiolabeling efficiency and radiochemical purity after purification were then characterized by TLC in vitro.LNCaP cells were inoculated in 96-well cell plate and divided into following groups (3 duplicate wells for each group):15 kBq 131I-K237was added in the experimental group,different doses of Na131I (5,10,15 kBq) were added in 3 negative control groups,15 kBq 131I-K237 with different doses of unlabeled K237 (1,2,4,8,16 μ g/μl) were added in 3 blocking groups,and PBS was added in blank control group.The cellular binding ratios were calculated after 48 h.LNCaP cells were inoculated in 24-well cell plate and divided into 3 groups:131I-K237group,which including 3 different dose subgroups (5,10,15 kBq) ; unlabeled K237 group,which including 3 different dose subgroups (1,2,4 μg/μl) ; blank control group with 100 μl PBS.All the cells were cultured for 48 h,then optical microscopy (OM) and fluorescence microscopy (FM) were used to observe the cell morphology ; DNA gel electrophoresis was conducted and flow cytometry (FCM) was used to estimate the apoptotic rate of LNCaP cells.One-way analysis of variance and the least significant difference (LSD)-t test were used to analyze the data.Results The labeling efficiency of 131I-K237 was (73.7±3.2) ％ and the radiochemical purity was (96.7±0.6) ％ after purification.The binding ratio of experimental group was (95.8±1.5)％,whereas the ratio of negative groups with 5,10,15 kBq Na131I and PBS group was (8.2±0.4) ％,(8.3±0.6) ％,(8.6±0.5) ％ and 0,respectively.The binding ratio of 131I-K237 and LNCaP significantly declined with the increased dose of unlabeled K237 (t=4.71,P＜0.01).The apoptosis of LNCaP cells cultured with 131I-K237 was observed.Typical DNA ladder was found by DNA gel electrophoresis.The apoptotic rates of 5,10,15 kBq131I-K237 groups were (34.1±2.9)％,(37.3±3.4)％ and (41.7±3.6)％,respectively; whereas those of unlabeled K237 groups and blank control group were (10.8±1.0) ％,(12.5±2.1) ％,(13.1±2.4) ％ and (2.9±0.3) ％,respectively.There were significant differences of apoptotic rate among groups (F=76.31,P＜0.05).The difference among 5,10,15 kBq 131I-K237 groups was statistically significant (t=3.09,3.27,4.52,all P＜0.05).Conclusion 131I-K237 can bind to LNCaP cells with highly affinity and has significant apoptosis-inducing efficacy on the prostate cancer cell line.
