Molecular docking analysis of compounds from Andrographis paniculata with EGFR

EGFR is linked with oral cancer. Therefore, it is of interest document the molecular docking analysis of compounds from Andrographis paniculata with EGFR. Data shows the binding features of five compounds 14- acetylandrographolide, andrograpanin, andrographolide, isoandrographolide and neoandrographolide from Andrographis paniculata with EGFR for further consideration.     

Molecular docking and in vitro analysis of phytoextracts from B. serrata for antibacterial activities

The bioactives of Boswellia serrata have a role in ulcer healing therapies. Eleven bioactive compounds were obtained by GC-MS among which Cholan-24-oic acid, 3,12-bis (acetyl oxy) has a high molecular weight of 490.6719 with a retention time of 26.729. Twenty wound samples were collected aseptically from the labs and hospitals in and around the Namakkal districts of Tamilnadu, India. The antibacterial potential of E.coli showed a maximum inhibition of 27 mm against Tetracycline at 30µg. The ethanolic extract of the B. serrata shows a susceptibility of 19mm towards E. coli at 60µg concentration in MIC. Molecular docking results show the binding energy of Cholan-24-oic acid, 3,12-bis(acetyloxy) -8.6 (kcal/mol) followed by Pyrene, hexadecahydro- -6.7 (kcal/mol), and 5(1H)- Azulenone, 2,4,6,7,8,8a-hexahydro-3,8-dimethyl-4-(1-methylethylidene)-, (8S-cis)- 6.4 (kcal/mol) for further consideration.     

Insights from the molecular docking aided interaction analysis of HfQ with small RNAs

Hfq, RNA binding protein, is widely found in most of the prokaryotes. It plays a key role in gene regulation by binding with small RNA and facilitates mRNA pairing there by suppress or boost translation according to RNA structures. Interaction between sRNAs and HfQ in Salmonella SL1344 were screened using Co-Immuno Precipitation (HfQ-CoIP) studies earlier. We have formulated an In silico approach, to model the 3D structures of 155 sRNA and studied their interactions with HfQ proteins. We have reported the key interacting PHE42, LEU7, VAL27, PHE39 and PRO21 residues of HfQ binds with many small RNAs. Further mutation of PHE42 in to ALA42 in HfQ leads to loss of sRNA binding efficiency. We have differentiated the interactions in to HfQ binding and non-binding sRNAs, based on Atomic Contact Energy and area. This methodology may be applied generically for functional grouping of small RNAs in any organism.     

Insights from the molecular docking analysis of colistin with the PmrA protein model from Acinetobacter baumannii

Acinetobacter baumannii (AB) is one of the most common causes of nosocomial infections. Therefore, it is of interest to design and develop drugs against Acinetobacter baumannii. A strain of AB showing MIC 32 µg/ml against colistin was isolated from a hospital environment in Iran. Hence, we document data to glean insights from the molecular docking analysis of colistin with the PmrA protein from this bacterium.     

Click chemistry based synthesis,cytotoxic activity and molecular docking of novel triazole-thienopyrimidine hybrid glycosides targeting EGFR

In the current study, new thienopyrimidine conjugates bearing 1,2,3-triazole core and different sugar moieties have been designed and synthesized by Cu(I)-catalysed click dipolar cycloaddition. The cytotoxic activity of the synthesised conjugates 2, 5, 7, and 13–18 was studied against HCT-116 and MCF-7 cell lines by the MTT assay. The triazole glycosides 16 and 18 provided significant cytotoxic activities against HCT-116 cell lines comparable to that of doxorubicin and other studied compounds. The cytotoxic behaviour against MCF-7 exhibited that all the investigated compounds were more potent than doxorubicin. Moreover, all screened targets were evaluated against mutant EGFR kinase type L858R and the results revealed that the acetylated 1,2,3-triazole glycosides 13–18 exhibited excellent EGFR inhibitory activity in comparison with gefitinib. Furthermore, molecular modelling studies were performed to investigate the binding affinity of the most active compounds to EGFR enzyme.     

Synthesis, molecular docking and evaluation of thiazolyl-pyrazoline derivatives as EGFR TK inhibitors and potential anticancer agents

Fourty-two thiazolyl-pyrazoline derivatives were synthesized to screen for their EGFR kinase inhibitory activity. Compound 4-(4-chlorophenyl)-2-(3-(3,4-dimethylphenyl)-5-p-tolyl-4,5-dihydro-1H-pyrazol-1-yl)thiazole (11) displayed the most potent EGFR TK inhibitory activity with IC(50) of 0.06 μM, which was comparable to the positive control. Molecular docking results indicated that compound 11 was nicely bound to the EGFR kinase. Compound 11 also showed significant antiproliferative activity against MCF-7 with IC(50) of 0.07 μM, which would be a potential anticancer agent.     

Synthesis and biological evaluation of 2-styrylquinolines as antitumour agents and EGFR kinase inhibitors: molecular docking study

A new series of 4,6-disubstituted 2-(4-(dimethylamino)styryl)quinoline 4a,b–9a,b was synthesized by the reaction of 2-(4-(dimethylamino)styryl)-6-substituted quinoline-4-carboxylic acids 3a,b with thiosemicarbazide, p-hydroxybenzaldehyde, ethylcyanoacetate, and 2,4-pentandione. In addition, the antitumour activity of all synthesized compounds 3a,b–9a,b was studied via MTT assay against two cancer cell lines (HepG2 and HCT116). Furthermore, epidermal growth factor receptor (EGFR) inhibition, using the most potent antitumour compounds, 3a, 3b, 4a, 4b, and 8a, was evaluated. The interpretation of the results showed clearly that the derivatives 3a, 4a, and 4b exhibited the highest antitumour activities against the tested cell lines HepG2 and HCT116 with IC₅₀ range of 7.7–14.2?µg/ml, in comparison with the reference drugs 5-fluorouracil (IC₅₀?=?7.9 and 5.3?µg/ml, respectively) and afatinib (IC₅₀?=?5.4 and 11.4?µg/ml, respectively). In vitro EGFR screening showed that compounds 3a, 3b, 4a, 4b, and 8a exhibited moderate inhibition towards EGFR with IC₅₀ values at micromolar levels (IC₅₀ range of 16.01–1.11?µM) compared with the reference drugs sorafenib (IC₅₀ =?1.14?µM) and erlotinib (IC₅₀ =?0.1?µM). Molecular docking was performed to study the mode of interaction of compounds 3a and 4b with EGFR kinase.     

Design and synthesis of quinazolinones as EGFR inhibitors to overcome EGFR resistance obstacle

The epidermal growth factor receptor (EGFR) T790M mutant is found in about 50% of clinically acquired resistance to gefitinib among patients with non-small cell lung cancer (NSCLC). New derivatives of 4(3H)-quinazolinones were synthesized and evaluated for their inhibitory activity against NSCLC. The results of the study demonstrated that compound 79, 7-chloro-3-(5-(4-methoxyphenyl)-1,3,4-thiadiazol-2-yl)-2-phenylquinazolin-4(3H)-one was found to be the most potent compounds of the series with IC₅₀ value of 0.031 μM against mutant T790M/L858R EGFR. Compounds 15, 51, 73, 75, 78, 79 and 96 were less potent against A549 (WT EGFR and k-Ras mutation) and HT-29 (non-special gene type) cells, showing a high safety index. The obtained results showed that compounds 15, 51, 73, 75, 78, 79 and 96 could be the promising template to overcome drug resistance mediated by the EGFR T790 Mutant.     

Insights from the molecular docking of curcumin to the virulent factors of Helicobacter pylori

The domains of virulent (Ureα/β, VacA-p55, and CagA) factors of Helicobacter pylori play a pivotal role in developmentalprocesses of numerous diseases including gastric cancer. The pharmacological role of curcumin indicates that it could regulate thesignaling of virulent factors by interacting with active domains. However, the controlling mechanism of the curcumin interactionsand the binding diversity on structural basis of virulent (Ureα/β, VacA-p55, and CagA) factors are unknown. Curcumin astherapeutic agent was filtered by using Lipinski rule׳s five and the druglikeness property for assessment of pharmacologicalproperties. Here outcome of molecular docking presented the 3-D structure of curcumin complex, that interacted with especiallyconserved residues of target domains. The structure revealed that the curcumin complexation with domains of these proteinsprovided structural insight into the diverse nature of proteins (Ureα/β, VacA-p55, and CagA) recognition. In silico studyelucidated that the broad specificity of curcumin was achieved by multiple binding mode mechanisms such as distinct hydrogenand hydrophobic interactions with involvement of binding energy. The higher score of curcumin in complexation with bothsubunits Ureα/β showed the stable binding, and less stability with VacA-p55 complexation with lower score. Curcumin exhibitedgood interaction with these targeted virulent factors, although extensive interactions of curcumin with Ureα/β subunits could havean important implication to prevent survival and colonisation of H. pylori in stomach.     

Computational analysis of EGFR inhibition by Argos

Argos, a secreted inhibitor of the Drosophila epidermal growth factor receptor, and the only known secreted receptor tyrosine kinase inhibitor, acts by sequestering the EGFR ligand Spitz. We use computational modeling to show that this biochemically-determined mechanism of Argos action can explain available genetic data for EGFR/Spitz/Argos interactions in vivo. We find that efficient Spitz sequestration by Argos is key for explaining the existing data and for providing a robust feedback loop that modulates the Spitz gradient in embryonic ventral ectoderm patterning. Computational analysis of the EGFR/Spitz/Argos module in the ventral ectoderm shows that Argos need not be long-ranged to account for genetic data, and can actually have very short range. In our models, Argos with long or short length scale functions to limit the range and action of secreted Spitz. Thus, the spatial range of Argos does not have to be tightly regulated or may act at different ranges in distinct developmental contexts.     

Insights from the molecular docking of withanolide derivatives to the target protein PknG from Mycobacterium tuberculosis

A crucial virulence factor for intracellular Mycobacterium tuberculosis survival is Protein kinase G (PknG), a eukaryotic-like serinethreonine protein kinase expressed by pathogenic mycobacteria that blocks the intracellular degradation of mycobacteria in lysosomes. Inhibition of PknG results in mycobacterial transfer to lysosomes. Withania somnifera, a reputed herb in ayurvedic medicine, comprises a large number of steroidal lactones known as withanolides which show various pharmacological activities. We describe the docking of 26 withanferin and 14 withanolides from Withania somnifera into the three dimensional structure of PknG of M. tuberculosis using GLIDE. The inhibitor binding positions and affinity were evaluated using scoring functions- Glidescore. The withanolide E, F and D and Withaferin - diacetate 2 phenoxy ethyl carbonate were identified as potential inhibitors of PknG. The available drug molecules and the ligand AX20017 showed hydrogen bond interaction with the aminoacid residues Glu233 and Val235. In addition to Val235 the other amino acids, Gly237, Gln238 and Ser239 are important for withanolide inhibitor recognition via hydrogen bonding mechanisms.     

Novel irreversible EGFR tyrosine kinase inhibitor 324674 sensitizes human colon carcinoma HT29 and SW480 cells to apoptosis by blocking the EGFR pathway

Background

Epidermal growth factor receptor (EGFR) is widely expressed in multiple solid tumors including colorectal cancer by promoting cancer cell growth and proliferation. Therefore, the inhibition of EGFR activity may establish a clinical strategy of cancer therapy.

Methods

In this study, using human colon adenocarcinoma HT29 and SW480 cells as research models, we compared the efficacy of four EGFR inhibitors in of EGFR-mediated pathways, including the novel irreversible inhibitor 324674, conventional reversible inhibitor AG1478, dual EGFR/HER2 inhibitor GW583340 and the pan-EGFR/ErbB2/ErbB4 inhibitor. Cell proliferation was assessed by MTT analysis, and apoptosis was evaluated by the Annexin-V binding assay. EGFR and its downstream signaling effectors were examined by western blotting analysis.

Results

Among the four inhibitors, the irreversible EGFR inhibitor 324674 was more potent at inhibiting HT29 and SW480 cell proliferation and was able to efficiently induce apoptosis at lower concentrations. Western blotting analysis revealed that AG1478, GW583340 and pan-EGFR/ErbB2/ErbB4 inhibitors failed to suppress EGFR activation as well as the downstream mitogen-activated protein kinase (MAPK) and PI3K/AKT/mTOR (AKT) pathways. In contrast, 324674 inhibited EGFR activation and the downstream AKT signaling pathway in a dose-dependent manner.

Conclusion

Our studies indicated that the novel irreversible EGFR inhibitor 324674 may have a therapeutic application in colon cancer therapy.     

Disruptin,a cell-penetrating peptide degrader of EGFR: Cell-Penetrating Peptide in Cancer Therapy

Disruptin is a cell-permeable decoy peptide designed to destabilize activated EGFR, both by inhibiting Hsp90 chaperoning and dissociating the active asymmetric EGFR dimer, which leads to an increase in engagement of activated EGFR with the proteolytic degradation machinery and subsequent loss from the cells. Disruptin is an N-terminally biotinylated nonadecapeptide, with 8 amino acids from the αC-helix-β4 sheet loop of EGFR (S⁷⁶⁷-C⁷⁷⁴) fused to a TAT undecapeptide. The S⁷⁶⁷-R⁷⁷⁵ loop is at the interface with juxtamembrane domains in the active EGFR dimers and is a binding site for Hsp90. Cellular studies in EGFR-activated tumor cells demonstrated that Disruptin causes the disappearance of EGFR protein from cells over a few hours, a growth inhibitory effect, similar but more effective than the EGFR kinase inhibition. Interestingly, cells without activated EGFR remained unaffected. In vivo studies showed that Disruptin slowed the growth of small tumors. Larger tumors responded to intratumoral injections but did not respond to systemic administration at tolerated doses. Investigation of these results revealed that systemic administration of Disruptin has acute toxicities, mainly related to its TAT peptide moiety. Therefore, we conclude that although the efficacy of both in vitro and in vivo intratumoral injection of Disruptin supports the therapeutic strategy of blocking activated EGFR dimerization, Disruptin is not suitable for further development. These studies also highlight the importance of the chosen models and drug-delivery methods for such investigations.     

Destabilization of the Epidermal Growth Factor Receptor (EGFR) by a Peptide That Inhibits EGFR Binding to Heat Shock Protein 90 and Receptor Dimerization

An eight-amino acid segment is known to be responsible for the marked difference in the rates of degradation of the EGF receptor (ErbB1) and ErbB2 upon treatment of cells with the Hsp90 inhibitor geldanamycin. We have scrambled the first six amino acids of this segment of the EGF receptor (EGFR), which lies in close association with the ATP binding cleft and the dimerization face. Scrambling these six amino acids markedly reduces EGFR stability, EGF-stimulated receptor dimerization, and autophosphorylation activity. Two peptides were synthesized as follows: one containing the wild-type sequence of the eight-amino acid segment, which we call Disruptin; and one with the scrambled sequence. Disruptin inhibits Hsp90 binding to the EGFR and causes slow degradation of the EGFR in two EGFR-dependent cancer cell lines, whereas the scrambled peptide is inactive. This effect is specific for EGFR versus other Hsp90 client proteins. In the presence of EGF, Disruptin, but not the scrambled peptide, inhibits EGFR dimerization and causes rapid degradation of the EGFR. In contrast to the Hsp90 inhibitor geldanamycin, Disruptin inhibits cancer cell growth by a nonapoptotic mechanism. Disruptin provides proof of concept for the development of a new class of anti-tumor drugs that specifically cause EGFR degradation.     

同时提取光果甘草中光甘草定和甘草酸的工艺研究

本文主要对光果甘草中光甘草定、甘草酸两种重要活性成分的同时提取工艺进行了研究。通过单因素试验确定了影响提取的主要因素及适宜水平范围,通过正交试验确定了其最佳提取条件为:用含0.6%氨水的60%乙醇溶液作为提取剂,料液比为1∶20(w:v),在75℃条件下提取2 h。最佳提取条件下光甘草定的得率为0.238%±0.002%,甘草酸的得率为5.08%±0.03%。该工艺操作简单,投入一批原料,即可同时提取其中的光甘草定和甘草酸,为实现甘草资源高附加值的综合加工利用奠定了基础。     

整合素与EGFR 受体家族相互作用在乳腺癌中的作用研究进展

整合素与表皮生长因子受体（epithelial growth factor receptor,EGFR）在乳腺癌的发生、进展、侵袭与转移过程中发挥着重要的作用。在乳腺癌中,多种整合素的功能都与细胞的粘附相关,而EGFR 与细胞增殖、转移密切相关,过表达的整合素和EGFR 受体家族预示着预后不良。通过与受体结合,形成同源或异源二聚体,被活化的受体激活下游的信号蛋白,调节由细胞外至细胞内的信号途径,由此将刺激信号传入细胞内,从而控制细胞的增殖、转移等细胞生命事件,实现促进肿瘤进展与转移的作用。本文就整合素与EGFR 之间的相互作用在乳腺癌中的作用、对乳腺癌治疗策略及新药研发方向的影响进行综述。     

Design,synthesis, biological evaluation,QSAR analysis and molecular modelling of new thiazol-benzimidazoles as EGFR inhibitors

Heterocyclic rings such as thiazole and benzimidazole are considered as privileged structures, since they constitute several FDA-approved drugs for cancer treatment. In this work, a new set of 2-(2-(substituted) hydrazinyl)-4-(1-methyl-1H-benzo[d]imidazol-2-yl) thiazoles 4a-q were designed as epidermal growth factor receptor (EGFR) inhibitors and synthesized using concise synthetic methods. The new target compounds have been evaluated in vitro for their suppression activity against EGFR TK. Compounds 4n, 4h, 4i, 4a and 4d exhibited significant potency in comparison with erlotinib which served as a reference drug (IC50, 71.67–152.59 nM; IC50 erlotinib, 152.59 nM). Furthermore, MTT assay revealed that compounds 4j, 4a, 4f, 4h, 4n produced the most promising cytotoxic potency against the human breast cancer cell line (MCF-7) (IC50; 5.96–11.91 µM; IC50 erlotinib; 4.15 µM). Compound 4a showed promising activity as EGFR TK inhibitor as well as anti-breast cancer agent. In addition, 4a induced apoptotic effect and cell cycle arrest at G2/M phase preventing the mitotic cycle in MCF-7 cells. Moreover, 4a upregulated the oncogenic parameters; caspase-3, p53, Bax/Bcl-2 as well as it inhibited the level of PARP-1 enzyme. QSAR study was carried out for the new derivatives and it revealed the goodness of the models. Furthermore, molecular docking studies represented the binding modes of the promising compounds in the active pocket of EGFR.     

Effect of simvastatin on the resistance to EGFR tyrosine kinase inhibitors in a non-small cell lung cancer with the T790M mutation of EGFR

Although non-small cell lung cancer (NSCLC) tumors with activating mutations in the epidermal growth factor receptor (EGFR) are highly responsive to EGFR tyrosine kinase inhibitors (TKIs) including gefitinib and erlotinib, development of acquired resistance is almost inevitable. Statins show antitumor activity, but it is unknown whether they can reverse EGFR-TKIs resistance in NSCLC with the T790M mutation of EGFR. This study investigated overcoming resistance to EGFR-TKI using simvastatin. We demonstrated that addition of simvastatin to gefitinib enhanced caspase-dependent apoptosis in T790M mutant NSCLC cells. Simvastatin also strongly inhibited AKT activation, leading to suppression of β-catenin activity and the expression of its targets, survivin and cyclin D1. Both insulin treatment and AKT overexpression markedly increased p-β-catenin and survivin levels, even in the presence of gefitinib and simvastatin. However, inhibition of AKT by siRNA or LY294002 treatment decreased p-β-catenin and survivin levels. To determine the role of survivin in simvastatin-induced apoptosis of gefitinib-resistant NSCLC, we showed that the proportion of apoptotic cells following treatment with survivin siRNA and the gefitinib–simvastatin combination was greater than the theoretical additive effects, whereas survivin up-regulation could confer protection against gefitinib and simvastatin-induced apoptosis. Similar results were obtained in erlotinib and simvastatin-treated HCC827/ER cells. These findings suggest that survivin is a key molecule that renders T790M mutant NSCLC cells resistant to apoptosis induced by EGFR-TKIs and simvastatin. Overall, these data indicate that simvastatin may overcome EGFR-TKI resistance in T790M mutant NSCLCs via an AKT/β-catenin signaling-dependent down-regulation of survivin and apoptosis induction.