Ginsenoside Rg3 as a Potential Treatment for Metastatic Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a subtype of breast cancer for which no approved targeted therapy is available, and chemotherapy is the mainstay of the treatment for these patients. Administration of various chemotherapies can be limited by toxicities and the development of tumour resistance and the median overall survival of these patients is low. This research aimed at studying the efficacy of epimers of ginsenoside Rg3 (Rg3), 20(S)-Rg3 (SRg3) and 20(R)-Rg3 (RRg3), in inhibition of cancer growth and angiogenesis for the potential treatment of this disease. The preliminary molecular docking studies predicted that Rg3 interacted well with aquaporin 1 (AQP1), which plays important roles in cancer progression. First, stereoselectivity of Rg3 epimers was shown in inhibition of proliferation, migration and invasion of TNBC cell lines and blocking AQP1 water channel. Due to this stereoselectivity, the combination of both epimers was optimised for inhibition of loop formation in endothelial cells, using response surface methodology (RSM). It was shown that this optimised combination, referred to as C3, significantly inhibited the proliferation and migration of human and murine endothelial cells. Rg3 epimers worked as allosteric modulators of vascular endothelial growth factor receptor 2 (VEGFR2). C3 decreased the expression of VEGF and significantly decreased the expression of AQP1 and the phosphorylation of proteins downstream of AKT signalling in hypoxic and normoxic conditions. In TNBC monolayer cultures, C3 significantly decreased cell migration but did not inhibit cell proliferation. In TNBC mammospheres, C3 decreased mammosphere formation efficiency, with no significant reduction in cell viability. C3 decreased the expression of CD44 and the ratio of CD44/24. C3 also decreased the function of cells via affecting the proteins downstream of activation of the mammalian target of rapamycin (mTOR). In molecular docking, Rg3 epimers showed good binding scores with VEGFR2 and insulin growth factor-1 receptor amongst the tested tyrosine kinase receptors. Rg3 epimers also showed a good binding score with rapamycin-binding site of mTOR and activator of mTOR, Rheb. In a mouse model of metastatic TNBC, when an extrapolated dose of C3 (23 mg/kg SRg3 + 11 mg/kg RRg3) or an escalated dose (46 mg/kg SRg3 + 23 mg/kg RRg3) was injected into mice, a significant reduction in the primary tumour volume and decreased load of metastasis in the lungs was noticed. Furthermore, the number of affected axillary lymph nodes was significantly reduced. Since Rg3 is prone to extensive metabolism in vivo, the efficacy of deglycosylated metabolites of Rg3 epimers was also studied. It was shown that these metabolites were inhibitors of cell proliferation in TNBC and endothelial cells. The mechanism for this action was induction of necroptosis/necrosis in TNBC cell lines and apoptosis in endothelial cells. Among the tested metabolites, 20(S)-ginsenoside Rh2 (S-Rh2) showed the best inhibition of loop formation, and allosteric modulatory action on VEGFR2. It was also predicted to be a good blocker of the AQP1 water channel. Altogether, the findings of this project show the possibilities of Rg3, as a potential inhibitor of mTOR signalling for the treatment of TNBC patients.Thesis (Ph.D.) -- University of Adelaide, Adelaide Medical School, 202

Prevalence of vitamin D deficiency in healthy Iranian children : A systematic review and meta-analysis

Peer reviewedPublisher PD

Stereoselective Anti-Cancer Activities of Ginsenoside Rg3 on Triple Negative Breast Cancer Cell Models

Ginsenoside Rg3 (Rg3) has two epimers, 20(S)-ginsenoside Rg3 (SRg3) and 20(R)-ginsenoside Rg3 (RRg3), and while Rg3 itself has been reported to have anti-cancer properties, few studies have been reported on the anti-cancer effects of the different epimers. The aim was to investigate the stereoselective effects of the Rg3 epimers on triple negative breast cancer (TNBC) cell lines, tested using cell-based assays for proliferation, apoptosis, cell cycle arrest, migration and invasion. Molecular docking showed that Rg3 interacted with the aquaporin 1 (AQP1) water channel (binding score −9.4 kJ mol−1). The Xenopus laevis oocyte expression system was used to study the effect of Rg3 epimers on the AQP1 water permeability. The AQP1 expression in TNBC cell lines was compared with quantitative-polymerase chain reaction (PCR). The results showed that only SRg3 inhibited the AQP1 water flux and inhibited the proliferation of MDA-MB-231 (100 μM), due to cell cycle arrest at G0/G1. SRg3 inhibited the chemoattractant-induced migration of MDA-MB-231. The AQP1 expression in MDA-MB-231 was higher than in HCC1143 or DU4475 cell lines. These results suggest a role for AQP1 in the proliferation and chemoattractant-induced migration of this cell line. Compared to SRg3, RRg3 had more potency and efficacy, inhibiting the migration and invasion of MDA-MB-231. Rg3 has stereoselective anti-cancer effects in the AQP1 high-expressing cell line MDA-MB-231

Anti-Cancer Effects of an Optimised Combination of Ginsenoside Rg3 Epimers on Triple Negative Breast Cancer Models

Key problems of chemotherapies, as the mainstay of treatment for triple-negative breast cancer (TNBC), are toxicity and development of tumour resistance. Using response surface methodology, we previously optimised the combination of epimers of ginsenoside Rg3 (Rg3) for anti-angiogenic action. Here, we show that the optimised combination of 50 µM SRg3 and 25 µM RRg3 (C3), derived from an RSM model of migration of TNBC cell line MDA-MB-231, inhibited migration of MDA-MB-231 and HCC1143, in 2D and 3D migration assays (p < 0.0001). C3 inhibited mammosphere formation efficiency in both cell lines and decreased the CD44+ stem cell marker in the mammospheres. Molecular docking predicted that Rg3 epimers had a better binding score with IGF-1R than with EGFR, HER-2 or PDGFR, and predicted an mTOR inhibitory function of Rg3. C3 affected the signalling of AKT in MDA-MB-231 and HCC1143 mammospheres. In a mouse model of metastatic TNBC, an equivalent dose of C3 (23 mg/kg SRg3 + 11 mg/kg RRg3) or an escalated dose of 46 mg/kg SRg3 + 23 mg/kg RRg3 was administered to NSG mice bearing MDA-MB-231-Luc cells. Calliper and IVIS spectrum measurement of the primary and secondary tumour showed that the treatment shrunk the primary tumour and decreased the load of metastasis in mice. In conclusion, this combination of Rg3 epimers showed promising results as a potential treatment option for TNBC patients

Natural Blockers of PD-1/PD-L1 Interaction for the Immunotherapy of Triple-Negative Breast Cancer-Brain Metastasis

The limited treatment options for triple-negative breast cancer with brain metastasis (TNBC-BM) have left the door of further drug development for these patients wide open. Although immunotherapy via monoclonal antibodies has shown some promising results in several cancers including TNBC, it cannot be considered the most effective treatment for brain metastasis. This is due to the protective role of the blood–brain barrier (BBB) which limits the entrance of most drugs, especially the bulky ones such as antibodies, to the brain. For a drug to traverse the BBB via passive diffusion, various physicochemical properties should be considered. Since natural medicine has been a key inspiration for the development of the majority of current medicines, in this paper, we review several naturally-derived molecules which have the potential for immunotherapy via blocking the interaction of programmed cell death protein-1 (PD-1) and its ligand, PD-L1. The mechanism of action, physicochemical properties and pharmacokinetics of these molecules and their theoretical potential to be used for the treatment of TNBC-BM are discussed

Survey of Availability, Use and Knowledge about Toxicity of Diphenhydramine for Children among Iranian Mothers: Mothers Knowledge about Toxicity of Diphenhydramine for Infants

Diphenhydramine, as an antihistamine drug is widely used for the treatment of allergies. However, being classified as an over the counter medication and the general belief on the low adverse effect profile of this drug has made it widely accessible to the families. Recent reports of diphenhydramine intoxication and mortality, noticeably in children and infants have raised some serious concerns. In the present study, 241 mothers who referred to four different regional locations of mother and child health care service centers were asked to fill up a questionnaire on diphenhydramine. The results of our study showed that besides the lack of adequate information on the indications and safety of the drug, 97% of the mothers used this medication for different illness conditions of the children, with more than 20% misindications on respiratory infections, fever and pain conditions. More than 40% of mothers did not have specific idea about the age related restrictions of the medication and 81% had no information on the proper dose indication. Furthermore 86% of mothers had no information about its adverse effects and the rest of them knew only about drug induced drowsiness. The results of this study show that diphenhydramine usage should be more closely observed, the pharmacists should make consult families before providing them with diphenhydramine, the pharmaceutical companies should be obliged to provide a drug information sheet in the packaging, and the public media and various health care providers should also feel responsibility to forewarn mothers about the results of self-prescribed medication