{'fraction_non_alphanumeric': 0.03640897755610972, 'fraction_numerical': 0.0199501246882793, 'mean_word_length': 5.024024024024024, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Encapsulation in PLGA-PEG enhances 9- nitro-camptothecin cytotoxicity to human ovarian carcinoma cell line through apoptosis pathway

Ovarian cancer is the fifth leading cause of the cancer-related death among women. 9-nitrocamptothecin (9-NC) is a water-insoluble derivative of camptothecin used for the treatment of patients with advanced ovarian cancer. Previous studies showed that the encapsulation of 9-NC in poly (lactic-co-glycolic acid, PLGA) nanoparticles increased the cytotoxic effect of the drug on different cancer cell lines. In the present study, the cytotoxic effects of 9-NC, 9-NC-loaded PLGA and PLGA-polyethylene glycol (PLGA-PEG) nanoparticles with varying degree of PEG (5, 10, and 15%) were evaluated on human ovarian carcinoma cell line. Furthermore, the mode of cell death induced by 9-NC and the optimized 9-NC-loaded PLGA-PEG nanoparticles on A2780 cell line were investigated. 9-NC incorporating nanoparticles were prepared by nanopercipitation method and their physicochemical characteristics were evaluated using standard methods. The results showed that activation of caspase-3 and -9 significantly increased by free 9-NC and PLGA-PEG loaded nanoparticles in A2780 cells. In contrast to the free drug which increased the activation of caspase-8, 9-NC-loaded PLGA-PEG nanoparticles did not alter the activation of caspase-8. Collectively, it appears that apoptosis induced by 9-NC incorporated in PLGA-PEG 5% occurred through the activation of caspase-9 rather than activation of caspase-8 which is the mediator of extrinsic pathway. Moreover, our results confirmed that 9-NC in nanoparticles at the level of gene expression potentiated down-regulation of Bcl-2, up regulation of Bax, and Smac/DIABLO leading to a decrease in mitochondrial membrane potential. Taken together, our results showed that 9-NC incorporated in PLGA-PEG 5% nanoparticles is able to induce apoptosis in A2780 human ovarian carcinoma cells and has the potential for the treatment of ovarian carcinoma.