Design and synthesis of novel pyrazolopyrimidine candidates as promising EGFR-T790M inhibitors and apoptosis inducers

An innovative approach to development of new pyrazolylquinolin-2-one hybrids as dual EGFR and BRAFV600E inhibitors

Novel quinoline-based derivatives 2a-e and 4a-j have been designed and synthesized as potential antiproliferative agents. The designed compounds were screened for their antiproliferative activity against sixty cell lines according to NCI protocol. The promising hybrids 4d-g are screened by MTT assays on three cancer cell lines: leukemia (MOLT-4), lung cancer (HOP-92), and breast cancer (T47D), with IC50 values ranging from 4.982 ± 0.2 to 36.52 ± 1.46 µM compared to Staurosporine, with compound 4e being the most effective. Derivatives 4d-g were evaluated for their inhibitory activity on EGFR and BRAFV600E. Compound 4e exhibited the highest inhibitory activities, with IC50 values of 0.055 ± 0.002 μM for EGFR and 0.068 ± 0.003 μM for BRAFV600E, compared to the reference drugs erlotinib (IC50 0.06 ± 0.002 μM) and vemurafenib (IC50 0.035 ± 0.001 μM), respectively. Cell cycle analysis of the HOP-92 manifested that pre-G1 apoptosis signaling took place after 4e treatment. Docking simulations were employed to analyze the modes and scores of compounds 4d-g with respect to EGFR and BRAFV600E. The results revealed that compound 4e exhibited strong affinity for both EGFR and BRAFV600E compared to the reference drugs with values of - 3.226 and - 3.474 kcal/mol, respectively.

Integrative approaches to atrial fibrillation prevention and management: Leveraging gut health for improved cardiovascular outcomes in the aging population

Atrial fibrillation (AF) is a prevalent clinical arrhythmia associated with a high incidence and severe complications such as cerebral embolism and heart failure. While the etiology and pathogenesis of AF involve numerous factors, recent research emphasizes the significant role of intestinal microbiota imbalance in the emergence and progression of AF, particularly among older adults. This review investigates the mechanisms by which intestinal flora and their metabolites contribute to the onset of AF in the elderly, highlighting novel interactions between gut health and cardiac function. Current literature often overlooks these critical connections, indicating a substantial research gap in understanding how dysbiosis may exacerbate AF and hinder recovery. Furthermore, exploring the bidirectional relationship between the gut microbiome and systemic inflammation in the context of AF provides a unique perspective that has yet to be thoroughly investigated. Future research should focus on longitudinal studies assessing gut microbiota composition and function in AF patients and consider probiotics or prebiotics as potential adjunctive therapies for mitigating AF. This comprehensive approach may pave the way for innovative treatments integrating cardiology with gastroenterology, enhancing patient outcomes through a holistic understanding of health.

Dual EGFR and telomerase inhibitory potential of new triazole tethered Schiff bases endowed with apoptosis: design, synthesis, and biological assessments

Many cancers have displayed resistance to chemotherapeutic drugs over the past few decades. EGFR has emerged as a leading target for cancer therapy via inhibiting tumor angiogenesis. Besides, studies strongly suggest that blocking telomerase activity could be an effective way to control the growth of certain cancer cells. Based on the fact that multi-target design rationale can afford candidates with greater treatment effectiveness. Besides, it was evidenced that inhibition of human telomerase enhances the effect of some tyrosine kinase inhibitors. So, in the current work, we aimed to design and synthesize novel 1,2,3-triazole-tethered Schiff bases (5a-l) to act as dual EGFR and telomerase inhibitors. Growth inhibition (GI)% was conducted for the synthesized compounds using a panel of eleven cancer cell lines as well as two normal cell lines. Interestingly, compound 5e displayed the highest mean GI% (76.78%) among the investigated compounds surpassing the mean GI% of the reference drug doxorubicin (65.79%). In addition, compound 5g displayed notably the lowest IC50 values (13.31, 13.31, 12.62, and 31.19 μM) for the four utilized cancer cell lines HNO97, HCT116, A375, and HEPG2, respectively. Interestingly, the investigated compounds exhibited significant inhibitory potential to EGFR and telomerase protein expression; in particular, compound 5g recorded inhibitory potentials of 3.45 and 1.31 ng mL-1, respectively. Hence, protein expression of the apoptosis-related proteins was carried out for compound 5g. Pro-apoptotic proteins (caspases 3, 8, and 9) were upregulated by 1.35, 1.55, and 1.51-fold change, respectively. Meanwhile, the anti-apoptotic proteins (CDK-2, CDK-4, and CDK-6) were downregulated by 2.91, 2.01, and 9.15-fold change, respectively, ensuring the apoptotic potential of compound 5g. Accordingly, compound 5g was selected for further investigation of its effects on cell cycle progression in A375 cancer cells. Obviously, compound 5g prompted cell cycle arrest at the G0-G1 phase. Additionally, the investigated compounds showed eligible pharmacokinetic profiles with feasible oral bioavailability. Consequently, the synthesized compounds can be treated as lead multi-target anticancer ligands for future optimization.

Muti-target rationale design of novel substituted N-phenyl-2-((6-phenylpyridazin-3-yl)thio)acetamide candidates as telomerase/JAK1/STAT3/TLR4 inhibitors: In vitro and in vivo investigations

In this work, additional effort was applied to design new BIBR1532-based analogues with potential inhibitory activity against telomerase and acting as multitarget antitumor candidates to overcome the resistance problem. Therefore, novel substituted N-phenyl-2-((6-phenylpyridazin-3-yl)thio)acetamide candidates (4a-n) were synthesized. Applying the lead optimization strategy of the previously designed compound 8e; compound 4l showed an improved telomerase inhibition of 64.95 % and a superior growth inhibition of 79 % suggesting its potential use as a successful "multitarget-directed drug" for cancer therapy. Accordingly, compound 4l was further selected to evaluate its additional JAK1/STAT3/TLR4 inhibitory potentials. Compound 4l represented a very promising JAK1 inhibitory potential with a 0.46-fold change, compared to that of pacritinib reference standard (0.33-fold change). Besides, it showed a superior STAT3-inhibitory potential with a 0.22-fold change compared to sorafenib (0.33-fold change). Additionally, compound 4l downregulated TLR4 protein expression by 0.81-fold change compared to that of resatorvid (0.29-fold change). Also, molecular docking was performed to investigate the binding mode and affinity of the superior candidate 4l towards the four target receptors (telomerase, JAK1, STAT3, and TLR4). Furthermore, the therapeutic potential of compound 4l as an antitumor agent was additionally explored through in vivo studies involving female mice implanted with Solid Ehrlich Carcinoma (SEC). Remarkably, compound 4l led to prominent reductions in tumor size and mass. Concurrent enhancements in biochemical, hematologic, histopathologic, and immunohistochemical parameters further confirmed the suppression of angiogenesis and inflammation, elucidating additional mechanisms by which compound 4l exerts its anticancer effects.

Pyrazole, Pyrazoline, and Fused Pyrazole Derivatives: New Horizons in EGFR-Targeted Anticancer Agents

Pyrazole and its derivatives remain popular heterocycles in drug research, design, and development. Several drugs include the pyrazole scaffold, such as ramifenazone, ibipinabant, antipyrine, and axitinib, etc. They have been extensively studied by the scientific community and are said to have a wide range of biological activity, especially anticancer agents targeting EGFR. Overexpression of EGFR signalling promotes tumor growth by inhibiting apoptosis. EGFR dysfunction has been described in multiple cancers, including colon, head and neck, NSCLC, colon, liver, breast, and ovarian cancer. As a result, EGFR represents a prospective target for cancer treatment. Several anti-EGFR drugs are thriving, notably dacomitinib, afatinib, erlotinib, gefitinib, and osimertinib. However, almost all currently available anti-EGFR drugs have limited therapeutic effectiveness due to a lack of selectivity as well as substantial side effects. Furthermore, aberrant EGFR signalling across numerous human malignancies/carcinomas is impeded by gene amplification, protein overexpression, mutations, or in-frame deletions, making EGFR-induced cancer treatment challenging. To overcome such, novel therapeutic anti-EGFR drugs with high efficacy and minimal toxicity are required. To battle cancer and therapeutic resistance to EGFR inhibitors, pyrazole, pyrazoline, and their derivatives have been investigated as a viable pharmacophore for the development of new drugs with better potency, lesser toxicity, and favourable pharmacokinetic characteristics. The present investigation covers the examination of progress toward anti-cancer therapies targeting EGFR via pyrazole, pyrazoline, and fused pyrazole-based compounds. The current study also represents inclusive data on pyrazole-based marketed drugs as well as therapeutic candidates undergoing preclinical and clinical development. Lastly, we have discussed recent advances in the medicinal chemistry of pyrazole-based derivatives with their anti-EGFR significance for the eradication of various cancers and provide the direction toward structure-activity relationship (SAR), including mechanistic studies.

Multi-target rational design and synthesis of novel diphenyl-tethered pyrazolopyrimidines targeting EGFR and topoisomerase II with potential DNA intercalation and apoptosis induction

Herein, we envisioned the design and synthesis of novel pyrazolopyrimidines (confirmed by elemental analysis, 1H and 13C NMR, and mass spectra) as multitarget-directed drug candidates acting as EGFR/TOPO II inhibitors, DNA intercalators, and apoptosis inducers. The target diphenyl-tethered pyrazolopyrimidines were synthesized starting from the reaction of phenyl hydrazine and ethoxymethylenemalononitrile to give aminopyrazole-carbonitrile 2. The latter hydrolysis with NaOH and subsequent reaction with 4-chlorobenzaldhyde afforded the corresponding pyrazolo[3,4-d]pyrimidin-4-ol 4. Chlorination of 4 with POCl3 and sequential reaction with different amines afforded the target compounds in good yields (up to 73 %). The growth inhibition % of the new derivatives (6a-m) was investigated against different cancer and normal cells and the IC50 values of the most promising candidates were estimated for HNO97, MDA-MB-468, FaDu, and HeLa cancer cells. The frontier derivatives (6a, 6i, 6k, 6l, and 6m) were pursued for their EGFR inhibitory activity. Compound 6l decreased EGFR protein concentration by a 6.10-fold change, compared to imatinib as a reference standard. On the other side, compounds (6a, 6i, 6k, 6l, and 6m) underwent topoisomerase II (TOPO II) inhibitory assay. In particular, compounds 6a and 6l exhibited IC50s of 17.89 and 19.39 μM, respectively, surpassing etoposide with IC50 of 20.82 μM. Besides, the DNA fragmentation images described the great potential of both candidates 6a and 6l in inducing DNA degradation at lower concentrations compared to etoposide and doxorubicin. Moreover, compound 6l, with the most promising EGFR/TOPO II inhibition and DNA intercalation, was selected for further investigation for its apoptosis induction ability by measuring caspases 3, 7, 8, and 9, Bax, p53, MMP2, MMP9, and BCL-2 proteins. Additionally, molecular docking was used to explain the SAR results based on the differences in the molecular features of the investigated congeners and the target receptors' topology.

Investigating the Promising Anticancer Activity of Cetuximab and Fenbendazole Combination as Dual CBS and VEGFR-2 Inhibitors and Endowed with Apoptotic Potential

In this work, the cytotoxicity of monoclonal antibody (Cetuximab, Ce) and Fenbendazole (Fen), as well as their combination therapy were tested with the MTT assay. On the other side, Ce, Fen, and a combination between them were subjected to a colchicine-tubulin binding test, which was conducted and compared to Colchicine as a reference standard. Besides, Ce, Fen, and the combination of them were tested against the VEGFR-2 target receptor, compared to Sorafenib as the standard medication. Moreover, the qRT-PCR technique was used to investigate the levels of apoptotic genes (p53 and Bax) and anti-apoptotic gene (Bcl-2) as well. Also, the effect of Ce, Fen, and the combination of them on the level of ROS was studied. Furthermore, the cell cycle analysis and Annexin V apoptosis assay were carried out for Ce, Fen, and a combination of them. In addition, the molecular docking studies were used to describe the molecular levels of interactions for both (Fen and colchicine) or (Fen and sorafenib) within the binding pockets of the colchicine binding site (CBS) and vascular endothelial growth factor-2 receptor (VEGFR-2), respectively.