Design and Synthesis of New Thiophene/Thieno[2,3-d]pyrimidines along with Their Cytotoxic Biological Evaluation as Tyrosine Kinase Inhibitors in Addition to Their Apoptotic and Autophagic Induction

This work describes the synthesis and anticancer activity against kinase enzymes of newly designed thiophene and thieno[2,3-d]pyrimidine derivatives, along with their potential to activate autophagic and apoptotic cell death in cancer cells. The designed compounds were scanned for their affinity for kinases. The results were promising with affinity ranges from 46.7% to 13.3%. Molecular docking studies were performed, and the compounds were then screened for their antiproliferative effects. Interestingly, compounds 8 and 5 resulted in higher cytotoxic effects than the reference standard against MCF-7 and HepG-2. The compounds were evaluated for their induction of apoptosis and/or necrosis on HT-29 and HepG-2. Three compounds induced significant early apoptosis compared to untreated control HT-29 cells, and four derivatives were more significant compared to untreated HepG-2 cells. We further investigated the effect of four compounds on the autophagy process within HT-29, HepG-2, and MCF-7 cells with flow cytometry. Similar to the apoptosis results, compound 5 showed the highest autophagic induction among all compounds. The potential inhibitory activity of the synthesized compounds on kinases was assessed. Screened compounds showed inhibition activity ranging from 41.4% to 83.5%. Compounds recorded significant inhibition were further investigated for their specific FLT3 kinase inhibitory activity. Noticeably, Compound 5 exhibited the highest inhibitory activity against FLT3.

Phenylethanoid glycosides as a possible COVID-19 protease inhibitor: a virtual screening approach

From the beginning of pandemic more than 100 million people have been infected with a death rate higher than 2%. Indeed, the current exit strategy involving the spreading of vaccines must be combined with progress in effective treatments development. This scenario is sadly supported by the vaccine’s immune activation time and the inequalities in the global immunization schedule. Bringing the crises under control means providing the world population with accessible and impactful new therapeutics. We screened a natural product library that contains a unique collection of 2370 natural products into the binding site of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease (Mpro). According to the docking score and to the interaction at the active site, three phenylethanoid glycosides (forsythiaside A, isoacteoside and verbascoside) were selected. In order to provide better insight into the atomistic interaction and test the impact of the three selected compounds at the binding site, we resorted to a half microsecond-long molecular dynamics simulation. As a result, we are showing that forsythiaside A is the most stable molecule and it is likely to possess the highest inhibitory effect against SARS-CoV-2 Mpro. Phenylethanoid glycosides also have been reported to have both protease and kinase activity. This kinase inhibitory activity is very beneficial in fighting viruses inside the body as kinases are required for viral entry, metabolism, and/or reproduction. The dual activity (kinase/protease) of phenylethanoid glycosides makes them very promising anit-COVID-19 agents.

Characterization of LDD-2633 as a Novel RET Kinase Inhibitor with Anti-Tumor Effects in Thyroid Cancer

Rearranged during transfection (RET), a receptor tyrosine kinase, is activated by glial cell line-derived neurotrophic factor family ligands. Chromosomal rearrangement or point mutations in RET are observed in patients with papillary thyroid and medullary thyroid carcinomas. Oncogenic alteration of RET results in constitutive activation of RET activity. Therefore, inhibiting RET activity has become a target in thyroid cancer therapy. Here, the anti-tumor activity of a novel RET inhibitor was characterized in medullary thyroid carcinoma cells. The indirubin derivative LDD-2633 was tested for RET kinase inhibitory activity. In vitro, LDD-2633 showed potent inhibition of RET kinase activity, with an IC50 of 4.42 nM. The growth of TT thyroid carcinoma cells harboring an RET mutation was suppressed by LDD-2633 treatment via the proliferation suppression and the induction of apoptosis. The effects of LDD-2633 on the RET signaling pathway were examined; LDD-2633 inhibited the phosphorylation of the RET protein and the downstream molecules Shc and ERK1/2. Oral administration of 20 or 40 mg/kg of LDD-2633 induced dose-dependent suppression of TT cell xenograft tumor growth. The in vivo and in vitro experimental results supported the potential use of LDD-2633 as an anticancer drug for thyroid cancers.

Preclinical evaluation of LX-086, a small molecule as a selective inhibitor of PI3K.

e15662 Background: PI3K/Akt signaling pathway plays a key role in a series of cellular functions related to cell growth, proliferation, survival and differentiation. PI3Kα is ubiquitously expressed, and associates with angiogenesis and glucose homeostasis. Gain of function mutations in PIK3CA, the gene encoding the p110α catalytic subunit of PI3K, are among the most common somatic alterations in solid tumors. The purpose of this study is to investigate the in vitro/ in vivo antitumor activity, and safety of LX-086, a small molecule of PI3Kα selective inhibitor, in preclinical models of solid cancer with PIK3CA mutation or amplification. Methods: Kinase inhibitory activity and selectivity of LX-086 were determined with PI3K kinase assays. Cellular pAktS473 inhibitory activity and selectivity were evaluated in BT-474, MDA-MB-468, RAW264.7 and Jeko-1 cell lines (cell lines PI3Kα/β/γ/δ are specifically highly expressed respectively). The antitumor activity of LX-086 was evaluated in vivo in PIK3CA amplified or mutant breast cancer BT-474, T47D and ovarian cancer SK-OV-3 cell-derived mouse xenograft (CDX) models. Results: LX-086 displayed potent kinase inhibitory activity for WT PI3Kα, PI3KαE545K, PI3KαH1047R with IC50 1.80 nM/1.13 nM/0.69 nM, respectively. LX-086 inhibited cell pAktS473 in BT-474 cells with IC50 35.4 nM. The selectivity of LX-086 in PI3Kα over PI3Kβ/δ/γ is similar with that of alpelisib, which had been approved by FDA in 2019. LX-086 showed antitumor efficacy in HER2+/HR+, PIK3CA amplified breast cancer BT-474 CDX model (TGI = 106% @40 mpk, QD), as well as in the HER2-/HR+, PIK3CA H1047R breast cancer T47D CDX model ( TGI = 84.7%@ 40 mpk, QD) and PIK3CA H1047R ovarian cancer SK-OV-3 CDX model ( TGI = 69.2%@ 40 mpk, QD). The 28-days toxicity study in dog also indicated that LX-086 had similar therapeutic index with alpelisib, with low risk of hyperglycemia. Conclusions: We have identified a novel potent and safe PI3Kα inhibitor LX-086. Preclinical studies show antitumor efficacy of LX-086 in PIK3CA mutant and amplified solid cancer models. LX-086 represents a promising clinical candidate for the treatment of solid cancers with PIK3CA mutation or amplification.

INNO-406 inhibit the growth of chronic myeloid leukemia and promote its apoptosis via targeting PTEN

Background Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm. INNO-406 is a novel tyrosine kinase inhibitor (TKI) that possess specific Lyn kinase inhibitory activity with no or limited activity against other sarcoma (Src) family member kinases. The present study aimed to confirm the anti-tumor effect of INNO-406 on CML cells, and elucidate the molecular mechanism underlying its effect. Methods The cell proliferation and apoptosis were detected by MTT, western blot and flow cytometry respectively. Results As suggested by the findings, INNO-406 significantly inhibited the proliferation and induced apoptosis of CML cells. In addition, INNO-406 promoted the expression level of PETN. Rescue experiment revealed that PTEN knockdown reversed the effect of INNO-406 which indicated the correlation between INNO-406 and PTEN. Further study determined that PTEN inhibited the phosphorylation of AKT and 4EBP1 and subsequently altered the expression of apoptotic protein expressions including bax, cytochrome c (cyto-c), cleaved caspase3 and bcl-2. In vivo study further confirmed that INNO-406 inhibited the growth of CML cells in vivo by targeting PTEN. Conclusion Based on the above findings, this work extended our understanding of INNO-406 in the chemotherapy of CML and its molecular mechanism.