School Of Basic And Applied Sciences
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Item Genomic alterations associated with HER2+ breast cancer risk and clinical outcome in response to trastuzumab(Springer, 2019) Singla, H; Kaur, R.P; Shafi, G; Vashistha, R; Banipal, R.P.S; Kumar, Vinod; Munshi, AnjanaHuman epidermal growth factor receptor 2 positive (HER2+) breast cancer (BC) is an aggressive BC subtype characterized by HER2 overexpression/amplification. Genomic alterations of HER2 and others have been reported to be associated with, HER2 overexpression and prediction of trastuzumab-response. Here, we aimed at identifying germline and somatic alterations associated with HER2+ BC and evaluating their association with clinical outcome in response to trastuzumab therapy given to HER2+ BC patients. Global Sequencing Array (GSA) and polymerase chain reaction-restriction length polymorphism (PCR-RFLP) techniques were used to determine alterations in HER2 and other HER2-interacting as well as signaling-related genes in HER2+ BC. In addition, 20 formalin fixed paraffin-embedded tissue samples were also evaluated by GSA for identifying significant variations associated with HER + BC as well as response to trastuzumab therapy. A germline variant in HER2 (I655V) was found to be significantly associated with the risk of the disease (p < 0.01). A nonsense mutation in PTPN11 (K99X), a pathogenic CCND1 splice site variant (P241P), a hotspot missense mutation in PIK3CA (E542K) and a hotspot missense mutation in TP53 (R249S); were observed in 25%, 75%, 30% and 40% of the HER2+ BC tissue samples, respectively. Mutant CCND1 (P241P) and PIK3CA (E542K) were found to be significantly associated with reduced disease-free survival (DFS) in patients treated with trastuzumab (p: 0.018 and 0.005, respectively). These results indicate that HER2, PTPN11, CCND1 and PIK3CA genes are important biomarkers in HER2+ BC. Moreover, the patients harboring mutant CCND1 and PIK3CA exhibit a poorer clinical outcome as compared to those carrying wild-type CCND1 and PIK3CA. © 2018, Springer Nature B.V.Item 4,6-Diphenylpyrimidine Derivatives as Dual Inhibitors of Monoamine Oxidase and Acetylcholinesterase for the Treatment of Alzheimer's Disease(American Chemical Society, 2019) Kumar, B; Dwivedi, A.R; Sarkar, B; Gupta, S.K; Krishnamurthy, S; Mantha, Anil K; Parkash, Jyoti; Kumar, VinodAlzheimer's disease (AD) is a neurodegenerative disorder with multifactorial pathogenesis. Monoamine oxidase (MAO) and acetylcholinesterase enzymes (AChE) are potential targets for the treatment of AD. A total of 15 new propargyl containing 4,6-diphenylpyrimidine derivatives were synthesized and screened for the MAO and AChE inhibition activities along with ROS production inhibition and metal-chelation potential. All the synthesized compounds were found to be selective and potent inhibitors of MAO-A and AChE enzymes at nanomolar concentrations. VB1 was found to be the most potent MAO-A and BuChE inhibitor with IC 50 values of 18.34 ± 0.38 nM and 0.666 ± 0.03 μM, respectively. It also showed potent AChE inhibition with an IC 50 value of 30.46 ± 0.23 nM. Compound VB8 was found to be the most potent AChE inhibitor with an IC 50 value of 9.54 ± 0.07 nM and displayed an IC 50 value of 1010 ± 70.42 nM against the MAO-A isoform. In the cytotoxic studies, these compounds were found to be nontoxic to the human neuroblastoma SH-SY5Y cells even at 25 μM concentration. All the compounds were found to be reversible inhibitors of MAO-A and AChE enzymes. In addition, these compounds also showed good neuroprotective properties against 6-OHDA- and H 2 O 2 -induced neurotoxicity in SH-SY5Y cells. All the compounds accommodate nicely to the hydrophobic cavity of MAO-A and AChE enzymes. In the molecular dynamics simulation studies, both VB1 and VB8 were found to be stable in the respective cavities for 30 ns. Thus, 4,6-diphenylpyrimidine derivatives can act as promising leads in the development of dual-acting inhibitors targeting MAO-A and AChE enzymes for the treatment of Alzheimer's disease. © 2018 American Chemical Society.Item Dipropargyl substituted diphenylpyrimidines as dual inhibitors of monoamine oxidase and acetylcholinesterase(Elsevier, 2019) Kumar, Bhupinder; Kumar, V; Prashar, V; Saini, S; Dwivedi, A.R; Bajaj, B; Mehta, D; Parkash, Jyoti; Kumar, VinodAlzheimer's disease (AD) is a multifactorial neurological disorder involving complex pathogenesis. Single target directed drugs proved ineffective and since last few years' different pharmacological strategies including multi-targeting agents are being explored for the effective drug development for AD. A total of 19 dipropargyl substituted diphenylpyrimidines have been synthesized and evaluated for the monoamine oxidase (MAO) and acetylcholinesterase (AChE) inhibition potential. All the compounds were found to be selective and reversible inhibitors of MAO-B isoform. These compounds also displayed good AChE inhibition potential with IC50 values in low micromolar range. AVB4 was found to be the most potent MAO-B inhibitor with IC50 value of 1.49 ± 0.09 μM and AVB1 was found to be the most potent AChE inhibitor with IC50 value of 1.35 ± 0.03 μM. In the ROS protection inhibition studies, AVB1 and AVB4 displayed weak but interesting activity in SH-SY5Y cells. In the cytotoxicity studies involving SH-SY5Y cells, both AVB1 and AVB4 were found to be non-toxic to the tissue cells. In the molecular dynamic simulation studies of 30 ns, the potent compounds were found to be quite stable in the active site of MAO-B and AChE. The results suggested that AVB1 and AVB4 are promising dual inhibitors and have the potential to be developed as anti-Alzheimer's drug. © 2019Item Synthesis, biological evaluation and molecular modeling studies of phenyl-/benzhydrylpiperazine derivatives as potential MAO inhibitors.(Elsevier, 2018) Kumar, Bhupinder; Sheetal; Mantha, Anil K.; Kumar, VinodMonoamine oxidase inhibitors (MAOIs) are potential drug candidates for the treatment of various neurological disorders like Parkinson's disease, Alzheimer's disease and depression. In the present study, two series of 4-substituted phenylpiperazine and 1-benzhydrylpiperazine (1-21) derivatives were synthesized and screened for their MAO-A and MAO-B inhibitory activity using Amplex Red assay. Most of the synthesized compounds were found selective for MAO-B isoform except compounds 3, 7, 8, 9 and 13 (MAO-A selective) while compound 11 was non-selective. In the current series, compound 12 showed most potent MAO-B inhibitor activity with IC50 value of 80 nM and compound 7 was found to be most potent MAO-A inhibitor with IC50 value of 120 nM and both the compounds were found reversible inhibitors. Compound 8 was found most selective MAO-A inhibitor while compound 20 was found most selective inhibitor for MAO-B isoform. In the cytotoxicity evaluation, all the compounds were found non-toxic to SH-SY5Y and IMR-32 cells at 25 µM concentration. In the ROS studies, compound 8 (MAO-A inhibitor) reduced the ROS level by 51.2% while compound 13 reduced the ROS level by 61.81%. In the molecular dynamic simulation studies for 30 ns, compound 12 was found quite stable in the active cavity of MAO-B. Thus, it can be concluded that phenyl- and 1-benzhydrylpiperazine derivatives are promising MAO inhibitors and can act as a lead to design potent, and selective MAO inhibitors for the treatment of various neurological disorders.Item 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, VinodA 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.Item Recent trends in anticancer drug development: Challenges and opportunities(Bentham Science Publishers B.V., 2017) Skvortsova, Ira-Ida; Kumar, Vinod[No abstract available]Item Chitosan-supported copper as an efficient and recyclable heterogeneous catalyst for A3/decarboxylative A3-coupling reaction(Elsevier Ltd, 2018) Kaur, Pavneet; Kumar, Bhupinder; Kumar, Vinod; Kumar, RakeshChitosan-supported copper (chit@copper) based heterogeneous catalysts have been explored for A3-coupling and decarboxylative A3-coupling. The developed protocol employs low catalyst loading, solventless condition and easy work-up for the synthesis of diversely substituted propargylamines. More importantly, the catalyst could be recovered and reused without any significant loss in the activity. This offer huge advantages as recyclability issues are rarely addressed in decarboxylative A3-coupling. Leaching studies were carried out using AAS and ICPMS analysis. It is envisaged that chit@copper catalysts can have potential applications in terms of efficiency and recyclability in the emerging area of decarboxylative C?H bond activation/functionalization strategies. ? 2018 Elsevier LtdItem Synthesis, Biological Evaluation and Molecular Modeling Studies of Propargyl‐Containing 2,4,6‐Trisubstituted Pyrimidine Derivatives as Potential Anti‐Parkinson Agents(Wiley, 2018) Kumar, Bhupinder; Kumar, Mohit; Dwivedi, Ashish Ranjan; Kumar, VinodMonoamine oxidase B (MAO‐B) inhibitors are potential drug candidates for the treatment of various neurological disorders including Parkinson's disease. A total of 20 new propargyl‐containing 2,4,6‐trisubstituted pyrimidine derivatives were synthesized and screened for MAO inhibition using Amplex Red assays. All the synthesized compounds were found to be reversible and selective inhibitors of the MAO‐B isoform at sub‐micromolar concentrations. MVB3 was the most potent MAO‐B inhibitor with an IC50 value of 0.38±0.02 μμ, whereas MVB6 (IC50=0.51±0.04 μμ) and MVB16 (IC50=0.48±0.06 μμ) were the most selective for MAO‐B with a selectivity index of more than 100‐fold. In cytotoxic studies, these compounds were found to be nontoxic to human neuroblastoma SH‐SY5Y cells at concentrations of 25 μm. MVB6 was found to decrease the intracellular level of reactive oxygen species to 68 % at 10 μm concentration, whereas other compounds did not produce significant changes in reactive oxygen species levels. In molecular modeling studies, MVB3 displayed strong binding affinity for the MAO‐B isoform with a dock score of −10.45, in agreement with the observed activity. All the compounds fitted well in the hydrophobic cavity of MAO‐B. Thus, propargyl‐substituted pyrimidine derivatives can be promising leads in the development of potent, selective and reversible MAO‐B inhibitors for the treatment of Parkinson's disease.Item Synthesis, biological evaluation and molecular modeling studies of phenyl-/benzhydrylpiperazine derivatives as potential MAO inhibitors(Academic Press Inc., 2018) Kumar, Bhupinder; Sheetal; Mantha, Anil K.; Kumar, VinodMonoamine oxidase inhibitors (MAOIs) are potential drug candidates for the treatment of various neurological disorders like Parkinson's disease, Alzheimer's disease and depression. In the present study, two series of 4-substituted phenylpiperazine and 1-benzhydrylpiperazine (1?21) derivatives were synthesized and screened for their MAO-A and MAO-B inhibitory activity using Amplex Red assay. Most of the synthesized compounds were found selective for MAO-B isoform except compounds 3, 7, 8, 9 and 13 (MAO-A selective) while compound 11 was non-selective. In the current series, compound 12 showed most potent MAO-B inhibitor activity with IC50 value of 80 nM and compound 7 was found to be most potent MAO-A inhibitor with IC50 value of 120 nM and both the compounds were found reversible inhibitors. Compound 8 was found most selective MAO-A inhibitor while compound 20 was found most selective inhibitor for MAO-B isoform. In the cytotoxicity evaluation, all the compounds were found non-toxic to SH-SY5Y and IMR-32 cells at 25 ?M concentration. In the ROS studies, compound 8 (MAO-A inhibitor) reduced the ROS level by 51.2% while compound 13 reduced the ROS level by 61.81%. In the molecular dynamic simulation studies for 30 ns, compound 12 was found quite stable in the active cavity of MAO-B. Thus, it can be concluded that phenyl- and 1-benzhydrylpiperazine derivatives are promising MAO inhibitors and can act as a lead to design potent, and selective MAO inhibitors for the treatment of various neurological disorders. ? 2018 Elsevier Inc.Item Recent synthetic strategies for monocyclic azole nucleus and its role in drug discovery and development(Bentham Science Publishers B.V., 2018) Neha; Dwivedi, Ashish Ranjan; Kumar, Rakesh; Kumar, VinodBackground: In recent years, the development and diversification of heterocyclic compounds has become central to the discovery of bioactive compounds with novel or improved pharmacological properties. In particular, N-containing heterocycles are proved to be promising leads and drug candidates, and received huge attention of the medicinal chemists. Objective: Many drugs especially antibiotics are becoming obsolete due to the development of multidrug resistance. Moreover, toxicity and other side effects of some drugs necessitated the quest for safer and more potent drug candidates. The current review article described biological potential of various monocyclic azoles. Recent developments in the synthesis of azole derivatives have been also reviewed. Conclusion: The presence of N-heterocyclic rings can influence the pharmacokinetics, pharmacodynamics, pKa and bioavailability profile of the drug molecules. Compounds containing monocyclic azole rings showed various biological activities and number of molecules are in clinical practice. A number of important leads and potential drug candidates containing azole nucleus are in advance stages of drug developments. Thus, simple, atom economic and more efficient synthetic strategies are desired for the synthesis of new libraries of the compounds. ? 2018 Bentham Science Publishers.