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Success in cancer chemotherapy relies on efficient delivery of anti-neoplastic drugs, with minimal side-effects on non-cancerous cells. Nanoparticulation of prospective anti-cancer drugs, that were deemed unsuitable due to short biological half life, poor water solubility and low cellular permeability, has been hypothesized to generate superior chemotherapeutic agents, leading to reduced non-specific action and fewer side-effects. In lieu of the above, different synthetic modulations on the putative anti-cancer compound andrographolide (AG) were explored to improve its therapeutic efficiency. Our results indicated that PLGA-nanoparticulation of andrographolide diterpenoid enhanced its anti-cancer properties three fold. Chitosan coating of AG nanoparticles further accentuated cellular localization, induced G1 cell cycle arrest and increased cellular toxicity and apoptosis in MCF-7 cells. The charge modulated nanoparticles were seen to traverse more efficiently through the cytoplasm and accumulate in the nucleus, thus enhancing their anti-proliferative efficacy. In vivo studies confirm that the nanoparticles reduced tumor weight by 68.21% as compared to 24.7% by AG, and increased the life span of mice infected with Ehrlich ascites carcinoma (EAC) by 78.08% as compared to 23.5% for AG alone. This was achieved through development of slow release-type nanoparticle cargo delivery devices, and enhanced the efficiency of AGnps for targeting cancer cells. AG nanoparticles also showed sufficient promise as safe anti-cancer drugs since they had minimal impact on animal hematology. Hence, we successfully prepared non-toxic and delivery-efficient andrographolide nanoparticles, and established for the first time that PLGA-nanoparticulation of andrographolide and additional chitosan coating increased its anti-cancer efficacy in human breast cancer cells and mouse EAC model.

Artemisinin, a plant-derived antimalarial drug with relatively low toxicity on normal cells in humans, has selective anticancer activities in various types of cancers, both in vitro and in vivo. In the present study, we have investigated the anticancer effects of artemisinin in human cervical cancer cells, with special emphasis on its role in inducing apoptosis and repressing cell proliferation by inhibiting the telomerase subunits, ERα which is essential for maintenance of the cervix, and downstream components like VEGF, which is known to activate angiogenesis. Effects of artemisinin on apoptosis of ME-180 cells were measured by flow cytometry, DAPI, and annexin V staining. Expression of genes and proteins related to cell proliferation and apoptosis was quantified both at the transcriptional and translational levels by semi-quantitative RT-PCR and western blot analysis, respectively. Our findings demonstrated that artemisinin significantly downregulated the expression of ERα and its downstream component, VEGF. Antiproliferative activity was also supported by decreased telomerase activity and reduced expression of hTR and hTERT subunits. Additionally, artemisinin reduced the expression of the HPV-39 viral E6 and E7 components. Artemisinin-induced apoptosis was confirmed by FACS, nuclear chromatin condensation, annexin V staining. Increased expression of p53 with concomitant decrease in expression of the p53 inhibitor Mdm2 further supported that artemisinin-induced apoptosis was p53-dependent. The results clearly indicate that artemisinin induces antiproliferative and proapoptotic effects in HPV-39-infected ME-180 cells, and warrants further trial as an effective anticancer drug.

Hormone-induced breeding of fish has been effectively achieved with ovaprim, a salmon GnRH analog, in several teleost fish but not quite successfully in the Indian catfish. In order to analyze the rationale behind ovaprim ineffectiveness in this species, we investigated the effect of ovaprim injection on the GnRH receptors of the ovary and other extra-pituitary organs, since GnRH receptors are known to be over-expressed during spawning. RT-PCR analysis revealed that the GnRH receptor-II is present not only in the ovary, but also in the testis, liver and heart tissues of the catfish. However, the expression of the receptor declined in a time-dependent manner in response to ovaprim injection in all the above tissues. Concomitant changes were observed in the histology of the ovary, which indicated a decrease in the number of the immature ovarian follicles, thus elucidating the rationale behind partial success of ovaprim-induced spawning in the Indian catfish, as compared to other teleosts.

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