Nordamnacanthal potentiates the cytotoxic effects of tamoxifen in human breast cancer cells

Combination of tamoxifen and D-limonene enhances therapeutic efficacy in breast cancer cells

Breast cancer one of the most common diseases in women, has a high death and morbidity rate. Tamoxifen being very much effective in the chemoprevention of breast cancer has been shown to develop resistance during the course of treatment making it difficult for patient's survival. By combining tamoxifen with naturally occurring substances having similar activities, might control the toxicity and increase the susceptibility towards the treatment. As a natural compound, D-limonene has been reported to inhibit the growth of certain malignancies significantly. The main goal of our work is to investigate the combinatorial antitumor effects of D-limonene and tamoxifen in MCF-7 cells, as well as understand the potential underlying anticancer mechanism. MTT assays, colony formation assays, DAPI and Annexin V-FITC labeling, flow cytometer analysis, and western blot analysis were used to explore the details of anticancer mechanism. The combined effects of tamoxifen with D-limonene have shown significant decrease in the cell viability of MCF 7 cells. According to flow cytometer analyses and Annexin V/PI staining, D-limonene has been found to increase tamoxifen-mediated apoptosis as compared to the treatment alone in these cells. Additionally, cell growth has been found to be arrested at G1 phase by regulating cyclin D1 and cyclin B1. Our research consequently provided the first evidence that combining D-limonene and tamoxifen might increase the anticancer efficacy by inducing apoptosis in MCF 7 breast cancer cells. This combinatorial treatment strategy demands more research which might fulfill the need for improved treatment efficacy in controlling breast cancer.

Anticancer Potential of Damnacanthal and Nordamnacanthal from Morinda elliptica Roots on T-lymphoblastic Leukemia Cells

Background: This study reports on the cytotoxic properties of nordamnacanthal and damnacanthal, isolated from roots of Morinda elliptica on T-lymphoblastic leukaemia (CEM-SS) cell lines. Methods: MTT assay, DNA fragmentation, ELISA and cell cycle analysis were carried out. Results: Nordamnacanthal and damnacanthal at IC₅₀ values of 1.7 μg/mL and10 μg/mL, respectively. At the molecular level, these compounds caused internucleosomal DNA cleavage producing multiple 180–200 bp fragments that are visible as a “ladder” on the agarose gel. This was due to the activation of the Mg²⁺/Ca²⁺-dependent endonuclease. The induction of apoptosis by nordamnacanthal was different from the one induced by damnacanthal, in a way that it occurs independently of ongoing transcription process. Nevertheless, in both cases, the process of dephosphorylation of protein phosphates 1 and 2A, the ongoing protein synthesis and the elevations of the cytosolic Ca²⁺ concentration were not needed for apoptosis to take place. Nordamnacanthal was found to have a cytotoxic effect by inducing apoptosis, while damnacanthal caused arrest at the G0/G1 phase of the cell cycle. Conclusion: Damnacanthal and nordamnacanthal have anticancer properties, and could act as potential treatment for T-lymphoblastic leukemia.

Cytotoxic potential of Artemisia absinthium extract loaded polymeric nanoparticles against breast cancer cells: Insight into the protein targets

Targeted drug delivery system in the form of herbal based nano-formulations is the new ray of hope for minimizing the side effects related to the anti-cancer drugs as well as conventional drug delivery system. In view of this, the present study was designed to evaluate the cytotoxic potential of A. absinthium extract loaded polymeric nanoparticles (NVA-AA) against the breast cancer cell lines (MCF-7 and MDA MB-231) and to identify the protein targets for the caused cytotoxicity. The polymeric nanoparticles (PNPs) were prepared by free radical mechanism and loaded with the whole plant extract. The cytotoxicity of these NVA-AA were evaluated on the breast cancer cell lines via different cytotoxic parameters viz. MTT assay, CFSE proliferation assay, apoptosis assay, cell cycle study. The protein targets and the interaction among them were identified by nano-LCMS/MS analysis and STRING online tool respectively, which were further validated by qPCR and BLI. The LCMS/MS analysis suggests that the caused cytotoxicity was due to the alteration of proteins involved in vesicular trafficking, apoptosis, proliferation and metastasis. Further, interactome analysis identified UBA52 in MCF-7 and TIAL1, PPP1CC in MDA MB-231 cells as the central molecule in the vesicular trafficking and apoptosis networking connection.

Subchronic toxicity, immunoregulation and anti-breast tumor effect of Nordamnacantal, an anthraquinone extracted from the stems of Morinda citrifolia L

BACKGROUND

Morinda citrifolia L. that was reported with immunomodulating and cytotoxic effects has been traditionally used to treat multiple illnesses including cancer. An anthraquinone derived from fruits of Morinda citrifolia L., nordamnacanthal, is a promising agent possessing several in vitro biological activities. However, the in vivo anti-tumor effects and the safety profile of nordamnacanthal are yet to be evaluated.

METHODS

In vitro cytotoxicity of nordamnacanthal was tested using MTT, cell cycle and Annexin V/PI assays on human MCF-7 and MDA-MB231 breast cancer cells. Mice were orally fed with nordamnacanthal daily for 28 days for oral subchronic toxicity study. Then, the in vivo anti-tumor effect was evaluated on 4T1 murine cancer cells-challenged mice. Changes of tumor size and immune parameters were evaluated on the untreated and nordamnacanthal treated mice.

RESULTS

Nordamnacanthal was found to possess cytotoxic effects on MDA-MB231, MCF-7 and 4T1 cells in vitro. Moreover, based on the cell cycle and Annexin V results, nordamnacanthal managed to induce cell death in both MDA-MB231 and MCF-7 cells. Additionally, no mortality, signs of toxicity and changes of serum liver profile were observed in nordamnacanthal treated mice in the subchronic toxicity study. Furthermore, 50 mg/kg body weight of nordamncanthal successfully delayed the progression of 4T1 tumors in Balb/C mice after 28 days of treatment. Treatment with nordamnacanthal was also able to increase tumor immunity as evidenced by the immunophenotyping of the spleen and YAC-1 cytotoxicity assays.

CONCLUSION

Nordamnacanthal managed to inhibit the growth and induce cell death in MDA-MB231 and MCF-7 cell lines in vitro and cease the tumor progression of 4T1 cells in vivo. Overall, nordamnacanthal holds interesting anti-cancer properties that can be further explored.

A REVIEW ON THE CHEMISTRY AND PHARMACOLOGY OF Rennellia elliptica Korth

Rennellia elliptica, popularly dubbed as Malaysian Ginseng, is widely used in traditional medicine among the local Jakun community in Endau-Rompin State Park, Pahang, Malaysia. The decoction of the roots is traditionally taken for treatment of body aches, as postpartum tonic, as aphrodisiac and for the treatment of jaundice. In the effort of searching new botanical drugs and drug candidates from tropical rainforest, the team from this laboratory had conducted a sizeable phytochemical and biological screening program of tropical plant at Endau Rompin State Park, Pahang with the help from the indigenous people. R. elliptica showed strong antiplasmodial activity in vitro with the IC50 value of 4.04µg/mL. The comprehensive study on the root extract of R. elliptica in this laboratory yielded seventeen compounds from four different classes, including 2 new pyranoanthraquinones, one new anthraquinone, eleven known anthraquinones, one lactone triterpenoid, one coumarin and one phenolic acid. The chemical profile of the root extract was established using HPLC and the selected marker compounds were used as external standards and quantified using standard calibration curve. Nordamnacanthal 5, damnacanthal 7, 2-formyl-3-hydroxy-9,10-anthraquinone 6, 2-methyl-3-hydroxy-9,10-anthraquinone 11 and 1,2-dimethoxy-6-methyl-9,10-anthraquinone 3 were determined at 3.57, 10.32, 4.47, 12.18 and 4.09 µg/g, respectively. Owing to the toxicity of dichloromethane, the extraction of the desired marker compounds was attempted using accelerated solvent extraction and soxhlet extraction using ethanol and water at different compositions. R. elliptica root extract and the isolated anthraquinones showed potential antiplasmodial activity, and the active compounds were probed for their mode of action. In addition, the dichloromethane root extract of R. elliptica and the selected anthraquinones were screened for anticancer, antioxidant, and α-glucosidase inhibitory activities as well as toxicity study in vitro.  The review summarizes the findings on Rennellia elliptica which includes phytochemistry, toxicity and its biological activities. The chemotaxonomic significance of Rennellia elliptica is also discussed

Artonin E induces p53-independent G1 cell cycle arrest and apoptosis through ROS-mediated mitochondrial pathway and livin suppression in MCF-7 cells

Artonin E is a prenylated flavonoid compound isolated from the stem bark of Artocarpus elasticus. This phytochemical has been previously reported to be drug-like with full compliance to Lipinski's rule of five and good physicochemical properties when compared with 95% of orally available drugs. It has also been shown to possess unique medicinal properties that can be utilized in view of alleviating most human disease conditions. In this study, we investigated the cytotoxic mechanism of Artonin E in MCF-7 breast cancer cells, which has so far not been reported. In this context, Artonin E significantly suppressed the breast cancer cell's viability while inducing apoptosis in a dose-dependent manner. This apoptosis induction was caspase dependent, and it is mediated mainly through the intrinsic pathway with the elevation of total reactive oxygen species. Gene and protein expression studies revealed significant upregulation of cytochrome c, Bax, caspases 7 and 9, and p21 in Artonin E-treated MCF-7 cells, while MAPK and cyclin D were downregulated. Livin, a member of the inhibitors of apoptosis, whose upregulation has been noted to precede chemotherapeutic resistance and apoptosis evasion was remarkably repressed. In all, Artonin E stood high as a potential agent in the treatment of breast cancer.

Roles for miRNAs in endocrine resistance in breast cancer

Therapies targeting estrogen receptor alpha (ERα), including selective ER modulators such as tamoxifen, selective ER downregulators such as fulvestrant (ICI 182 780), and aromatase inhibitors such as letrozole, are successfully used in treating breast cancer patients whose initial tumor expresses ERα. Unfortunately, the effectiveness of endocrine therapies is limited by acquired resistance. The role of microRNAs (miRNAs) in the progression of endocrine-resistant breast cancer is of keen interest in developing biomarkers and therapies to counter metastatic disease. This review focuses on miRNAs implicated as disruptors of antiestrogen therapies, their bona fide gene targets and associated pathways promoting endocrine resistance.