Calcarea carbonica induces apoptosis in cancer cells in p53-dependent manner via an immuno-modulatory circuit Shilpi Saha, Dewan Md Hossain, Shravanti Mukherjee, Suchismita Mohanty, Minakshi Mazumdar, Sanhita Mukherjee, Uttam K Ghosh, Chaturbhuj Nayek, Chinta Raveendar, Anil Khurana, Rathin Chakrabarty, Gaurisankar Sa and Tanya Das
Abstract
Background Complementary medicines, including homeopathy, are used by many patients with cancer, usually alongside with conventional treatment. However, the molecular mechanisms underneath the anti-cancer effect, if any, of these medicines have still remained unexplored. To this end we attempted to evaluate the efficacy of calcarea carbonica, a homeopathic medicine, as an anti-cancer agent and to delineate the detail molecular mechanism(s) underlying calcerea carbonica-induced tumor regression.
Methods To investigate and delineate the underlying mechanisms of calcarea carbonica-induced tumor regression, Trypan blue dye-exclusion test, flow cytometric, Western blot and reverse transcriptase-PCR techniques were employed. Further, siRNA transfections and inhibitor studies were used to validate the involvement of p53 pathway in calcarea carbonica-induced apoptosis in cancer cells.
Results Interestingly, although calcarea carbonica administration to Ehrlich’s ascites carcinoma (EAC)- and Sarcoma-180 (S-180)-bearing Swiss albino mice resulted in 30-35% tumor cell apoptosis, it failed to induce any significant cell death in ex vivo conditions. These results prompted us to examine whether calcarea carbonica employs the immuno-modulatory circuit in asserting its anti-tumor effects. In tumor-bearing mice, there was profound depletion of CD4+ and CD8+ cells in peripheral blood, dominance of type-2 T helper cells and inhibition of T cell proliferation. Calcarea carbonica in turn prevented such loss of effector T cell repertoire, reversed type-2 cytokine bias and attenuated tumor-induced inhibition of T cell proliferation in tumor-bearing host. To confirm the role of immune system in calcarea carbonica-induced cancer cell death, a battery of cancer cells were co-cultured with calcarea carbonica-primed T cells. Our results indicated a “two-step” mechanism of the induction of apoptosis in tumor cells by calcarea carbonica i.e., (1) activation of the immune system of the host; and (2) induction of cancer cell apoptosis via immuno-modulatory circuit in p53-dependent manner by down-regulating Bcl-2:Bax ratio. Bax up-regulation resulted in mitochondrial transmembrane potential loss and cytochrome c release followed by activation of caspase cascade. Knocking out of p53 by RNA-interference inhibited calcarea carbonica-induced apoptosis thereby confirming the contribution of p53.
Conclusion These observations delineate the significance of immuno-modulatory circuit during calcarea carbonica-mediated tumor apoptosis. The molecular mechanism identified may serve as a platform for involving calcarea carbonica into immunotherapeutic strategies for effective tumor regression.
Effect of Homeopathic Medicines on Transplanted Tumors in Mice ES Sunila, Girija Kuttan, Preethi KC, Ramadasan Kuttan*
Amala Cancer Research Centre, Amala Nagar, Thrissur, Kerala State, India. 680555.
Abstract Ultra low doses used in homeopathic medicines are reported to have healing potential for various diseases but their action remains controversial. In this study we have investigated the antitumour and antimetastatic activity of selected homeopathic medicines against transplanted tumours in mice. It was found that Ruta graveolens 200c and Hydrastis canadensis 200c significantly increased the lifespan of Ehrlich Ascites Carcinoma and Dalton’s Lymphoma Ascites induced tumour-bearing animals by 49.7%, and 69.4% respectively. Moreover there was 95.6% and 95.8% reduction of solid tumour volume in Ruta 200c and Hydrastis 200c treated animals on the 31st day after tumour inoculation. Hydrastis 1M given orally significantly inhibited the growth of developed solid tumours produced by DLA cells and increased the lifespan of tumour bearing animals. Some 9 out of 15 animals with developed tumors were completely tumour free after treatment with Hydrastis 1M. Significant anti-metastatic activity was also found in B16F-10 melanoma-bearing animals treated with Thuja1M, Hydrastis 1M and Lycopodium1M. This was evident from the inhibition of lung tumour nodule formation, morphological and histopathological analysis of lung and decreased levels of γ-GT in serum, a cellular marker of proliferation. These findings support that homeopathic preparations of Ruta and Hydrastis have significant antitumour activity. The mechanism of action of these medicines is not known at present.