Browsing by Author "Dogra, Nilambra"

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    Design, synthesis and anticancer activity of 2-arylimidazo[1,2-a]pyridinyl-3-amines
    (Academic Press Inc., 2021-11-01T00:00:00) Yadav, Umesh Prasad; Ansari, Arshad J.; Arora, Sahil; Joshi, Gaurav; Singh, Tashvinder; Kaur, Harsimrat; Dogra, Nilambra; Kumar, Raj; Kumar, Santosh; Sawant, Devesh M.; Singh, Sandeep
    A series of imido-heterocycle compounds were designed, synthesized, characterized, and evaluated for the anticancer potential using breast (MCF-7 and MDA-MB-231), pancreatic (PANC-1), and colon (HCT-116 and HT-29) cancer cell lines and normal cells, while normal cells showed no toxicity. Among the screened compounds, 4h exhibited the best anticancer potential with IC50 values ranging from 1 to 5.5 ?M. Compound 4h caused G2/M phase arrest and apoptosis in all the cell lines except MDA-MB-231 mammosphere formation was inhibited. In-vitro enzyme assay showed selective topoisomerase II? inhibition by compound 4h, leading to DNA damage as observed by fluorescent staining. Cell signalling studies showed decreased expression of cell cycle promoting related proteins while apoptotic proteins were upregulated. Interestingly MDA-MB-231 cells showed only cytostatic effects upon treatment with compound 4h due to defective p53 status. Toxicity study using overexpression of dominant-negative mutant p53 in MCF-7 cells (which have wild type functional p53) showed that anticancer potential of compound 4h is positively correlated with p53 expression. � 2021 Elsevier Inc.
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    Eradicating Cancer Stem Cells: Concepts, Issues, and Challenges
    (Springer New York LLC, 2018) Kaur, Gurpreet; Sharma, Praveen; Dogra, Nilambra; Singh, Sandeep
    The cells of malignant cancers result in the evolution of cells with stem-like characteristics, commonly known as cancer stem cells (CSCs). Progress of anticancer therapies is severely hampered because of disease relapse mostly in a more aggressive form due to CSCs. These CSCs are more or less like embryonic or tissue stem cells, known for their capacity of self-renewal, exactly recapitulate of the original tumor. Deregulation of key stem cell pathways like Wnt, Hedgehog (Hh), and Notch is attributed towards the rise of CSCs. Recent breakthroughs offer better insights into CSC signaling. Scientists have developed several combinatorial therapies like targeting one/multiple of these CSC pathways. The article summarized various markers used to identify CSCs and discuss major signaling pathways in them. The futuristic probabilities to use CSC therapeutics in clinical development have been discussed. Our views have been highlighted on the future directions for targeting advances in the clinical development. ? 2018, Springer Science+Business Media, LLC, part of Springer Nature.
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    Let-7a induces metabolic reprogramming in breast cancer cells via targeting mitochondrial encoded ND4
    (BioMed Central Ltd, 2021-11-27T00:00:00) Sharma, Praveen; Sharma, Vibhuti; Ahluwalia, Tarunveer Singh; Dogra, Nilambra; Kumar, Santosh; Singh, Sandeep
    Background and objectives: MicroRNA (miRNA) that translocate from the nucleus to mitochondria are referred to as mitochondrial microRNA (mitomiR). Albeit mitomiRs have been shown to modulate gene expression, their functional impact within mitochondria is unknown. The main objective of this study is to investigate whether the mitochondrial genome is regulated by miR present inside the mitochondria. Methods and results: Here, we report mitomiR let-7a regulates mitochondrial transcription in breast cancer cells and reprogram the metabolism accordingly. These effects were mediated through the interaction of let-7a with mtDNA, as studied by RNA pull-down assays, altering the activity of Complex I in a cell line-specific manner. Our study, for the first time, identifies the role of mitomiR (let-7a) in regulating the mitochondrial genome by transcriptional repression and its contribution to regulating mitochondrial metabolism of breast cancer cells. Conclusion: These findings uncover a novel mechanism by which mitomiR regulates mitochondrial transcription. � 2021, The Author(s).
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    miR-30c and miR-181a synergistically modulate p53?p21 pathway in diabetes induced cardiac hypertrophy
    (Springer New York LLC, 2016) Raut, Satish K.; Singh, Gurinder B.; Rastogi, Bhawna; Saikia, Uma Nahar; Mittal, Anupam; Dogra, Nilambra; Singh, Sandeep; Prasad, Rishikesh; Khullar, Madhu
    p53?p21 pathway mediates cardiomyocyte hypertrophy and apoptosis and is upregulated in diabetic cardiomyopathy (DbCM). We investigated role of microRNAs in regulating p53?p21 pathway in high glucose (HG)-induced cardiomyocyte hypertrophy and apoptosis. miR-30c and miR-181a were identified to target p53. Cardiac expression of microRNAs was measured in diabetic patients, diabetic rats, and in HG-treated cardiomyocytes. Effect of microRNAs over-expression and inhibition on HG-induced cardiomyocyte hypertrophy and apoptosis was examined. Myocardial expression of p53 and p21 genes was increased and expression of miR-30c and miR-181a was significantly decreased in diabetic patients, DbCM rats, and in HG-treated cardiomyocytes. Luciferase assay confirmed p53 as target of miR-30c and miR-181a. Over-expression of miR-30c or miR-181a decreased expression of p53, p21, ANP, cardiomyocyte cell size, and apoptosis in HG-treated cardiomyocytes. Concurrent over-expression of these microRNAs resulted in greater decrease in cardiomyocyte hypertrophy and apoptosis, suggesting a synergistic effect of these microRNAs. Our results suggest that dysregulation of miR-30c and miR-181a may be involved in upregulation of p53?p21 pathway in DbCM. ? 2016, Springer Science+Business Media New York.
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    Synthesis and biological evaluation of pyrimidine bridged combretastatin derivatives as potential anticancer agents and mechanistic studies
    (Academic Press Inc., 2018) Kumar, Bhupinder; Sharma, Praveen; Gupta, Vivek Prakash; Khullar, Madhu; Singh, Sandeep; Dogra, Nilambra; Kumar, Vinod
    A number of pyrimidine bridged combretastatin derivatives were designed, synthesized and evaluated for anticancer activities against breast cancer (MCF-7) and lung cancer (A549) cell lines using MTT assays. Most of the synthesized compounds displayed good anticancer activity with IC50 values in low micro-molar range. Compounds 4a and 4p were found most potent in the series with IC50 values of 4.67 ?M & 3.38 ?M and 4.63 ?M & 3.71 ?M against MCF7 and A549 cancer cell lines, respectively. Biological evaluation of these compounds showed that selective cancer cell toxicity (in vitro using human lung and breast cancer cell lines) might be due to the inhibition of antioxidant enzymes instigating elevated ROS levels which triggers intrinsic apoptotic pathways. These compounds were found nontoxic to the normal human primary cells. Compound 4a, was found to be competitive inhibitor of colchicine and in the tubulin binding assay it showed tubulin polymerization inhibition potential comparable to colchicine. The molecular modeling studies also showed that the synthesized compounds fit well in the colchicine-binding pocket. ? 2018 Elsevier Inc.