Design, synthesis and antitumor activity of novel thiophene- triazine derivatives bearing arylurea unit as potent PI3K/mTOR inhibitorss

Current scenario of pyrazole hybrids with anti-breast cancer therapeutic applications

Breast cancer stands as the leading cause of cancer-related deaths among women globally, but current therapy is restricted to the serious adverse effects and multidrug resistance, necessitating the exploration of novel, safe, and efficient anti-breast cancer chemotherapeutic agents. Pyrazoles exhibit excellent potential for utilization as effective anti-breast cancer agents due to their ability to act on various biological targets. Particularly, pyrazole hybrids demonstrated the advantage of targeting multiple pathways, and some of them, which are exemplified by larotrectinib (pyrazolo[1,5-a]pyrimidine hybrid), can be applied for breast cancer therapy. Thus, pyrazole hybrids hold great promise as useful therapeutic interventions for breast cancer. The aim of this review is to summarize the current scenario of pyrazole hybrids with in vitro and/or in vivo anti-breast cancer potential, along with the modes of action and structure-activity relationships, covering articles published from 2020 to the present, to streamline the development of rational, effective and safe anti-breast cancer candidates.

Thiazolation of phenylthiosemicarbazone to access new thiazoles: anticancer activity and molecular docking

Aim: Novel thiazole hybrids were synthesized via thiazolation of 4-phenylthiosemicarbazone (4). Materials & methods: The anticancer activity against the NCI 60 cancer cell line panel. Results: Methyl 2-(2-((1-(naphthalen-2-yl)ethylidene)hydrazineylidene)-4-oxo-3-phenylthiazolidin-5-ylidene)acetate (6a) showed significant anticancer activity at 10 μM with a mean growth inhibition (GI) of 51.18%. It showed the highest cytotoxic activity against the ovarian cancer OVCAR-4 with an IC50 of 1.569 ± 0.06 μM. Compound 6a inhibited PI3Kα with IC50 = 0.225 ± 0.01 μM. Moreover, compound 6a revealed a decrease of Akt and mTOR phosphorylation in OVCAR-4 cells. In addition, antibacterial activity showed that compounds 11 and 12 were the most active against Staphylococcus aureus. Conclusion: Compound 6a is a promising molecule that could be a lead candidate for further studies.

Design, synthesis and biological evaluation of novel morpholinopyrimidine-5-carbonitrile derivatives as dual PI3K/mTOR inhibitors

In this study, novel morpholinopyrimidine-5-carbonitriles were designed and synthesized as dual PI3K/mTOR inhibitors and apoptosis inducers. The integration of a heterocycle at position 2, with or without spacers, of the new key intermediate 2-hydrazinyl-6-morpholinopyrimidine-5-carbonitrile (5) yielded compounds 6-10, 11a-c and 12a-h. The National Cancer Institute (USA) tested all compounds for antiproliferative activity. Schiff bases, 12a-h analogs, were the most active ones. The most promising compounds 12b and 12d exhibited excellent antitumor activity against the leukemia SR cell line, which is the most sensitive cell line, with IC50 0.10 ± 0.01 and 0.09 ± 0.01 μM, respectively, along with significant effects on PI3Kα/PI3Kβ/PI3Kδ with IC50 values of 0.17 ± 0.01, 0.13 ± 0.01 and 0.76 ± 0.04 μM, respectively, for 12b and 1.27 ± 0.07, 3.20 ± 0.16 and 1.98 ± 0.11, respectively, for 12d compared to LY294002. Compared to Afinitor, these compounds inhibited mTOR with IC50 values of 0.83 ± 0.05 and 2.85 ± 0.17 μM, respectively. Annexin-V and propidium iodide (PI) double labeling showed that compounds 12b and 12d promote cytotoxic leukemia SR apoptosis. Compounds 12b and 12d also caused a G2/M cell cycle arrest in the leukaemia SR cell line. The findings of this study indicate that the highest effect was observed for 12b, which was supported by western blot and docking analysis.

Development of new thieno[2,3-d]pyrimidines as dual EGFR and STAT3 inhibitors endowed with anticancer and pro-apoptotic activities

In part due to the resilience of cellular feedback pathways that develop therapeutic resistance to targeting the EGFR alone, using EGFR inhibitors alone was demonstrated to be unsuccessful in clinical trials. The over-activation of the signal transducer/activator of transcription 3 (STAT3) during the administration of an EGFR inhibitor is expected to play a substantial part in the failure and resistance of EGFR inhibitor treatment. Therein, we proposed a hypothesis that induced STAT3-mediated resistance to EGFR inhibition therapy could be addressed by a dual inhibition of EGFR and STAT3 method. To this end, we tried to discover new thieno[2,3-d]pyrimidine derivatives "5a-o". Results from the screening on A549 and MCF7 cancer cell lines revealed that compounds 5j and 5k showed two-digit nanomolar with appropriate safety towards the WI-38 cell line. The best molecules, 5j and 5k, were subjected to γ-radiation, and their cytotoxic efficacy didn't change after irradiation, demonstrating that not having to use it avoided its side effects. Compounds 5j and 5k demonstrated the highest inhibition when their potency was tested as dual inhibitors on EGFR 67 and 41 nM, respectively, and STAT3 5.52 and 3.34 nM, respectively, proved with in silico molecular docking and dynamic simulation. In light of the results presented above, the capacity of both powerful compounds to alter the cell cycle and initiate the apoptotic process in breast cancer MCF7 cells was investigated. Caspase-8, Bcl-2, Bax and Caspase-9 apoptotic indicators were studied.

Recent drug design strategies and identification of key heterocyclic scaffolds for promising anticancer targets

Cancer, a noncommunicable disease, is the leading cause of mortality worldwide and is anticipated to rise by 75% in the next two decades, reaching approximately 25 million cases. Traditional cancer treatments, such as radiotherapy and surgery, have shown limited success in reducing cancer incidence. As a result, the focus of cancer chemotherapy has switched to the development of novel small molecule antitumor agents as an alternate strategy for combating and managing cancer rates. Heterocyclic compounds are such agents that bind to specific residues in target proteins, inhibiting their function and potentially providing cancer treatment. This review focuses on privileged heterocyclic pharmacophores with potent activity against carbonic anhydrases and kinases, which are important anticancer targets. Evaluation of ongoing pre-clinical and clinical research of heterocyclic compounds with potential therapeutic value against a variety of malignancies as well as the provision of a concise summary of the role of heterocyclic scaffolds in various chemotherapy protocols have also been discussed. The main objective of the article is to highlight key heterocyclic scaffolds involved in recent anticancer drug design that demands further attention from the drug development community to find more effective and safer targeted small-molecule anticancer agents.

A comprehensive review of small molecules targeting PI3K pathway: Exploring the structural development for the treatment of breast cancer

Cancer stands as one of the deadliest diseases, ranking second in terms of its global impact. Despite the presence of numerous compelling theories concerning its origins, none have succeeded in fully elucidating the intricate nature of this ailment. Among the prevailing concerns in today's world, breast cancer proliferation remains a significant issue, particularly affecting females. The abnormal proliferation of the PI3K pathway emerges as a prominent driver of breast cancer, underscoring its role in cellular survival and proliferation. Consequently, targeting this pathway has emerged as a leading strategy in breast cancer therapeutics. Within this context, the present article explores the current landscape of anti-tumour drug development, focusing on structural activity relationships (SAR) in PI3K targeting breast cancer treatment. Notably, certain moieties like triazines, pyrimidine, quinazoline, quinoline, and pyridoxine have been explored as potential PI3K inhibitors for combating breast cancer. Various heterocyclic small molecules are undergoing clinical trials, such as Alpelisib, the first orally available FDA-approved drug targeting PI3K; others include buparlisib, pictilisib, and taselisib, which inhibit class I PI3K. These drugs are used for the treatment of breast cancer but still have various side effects with their high cost. Therefore, the primary goal of this review is to include all current advances in the development of anticancer medicines that target PI3K over-activation in the treatment of breast cancer.

Design, synthesis, and anticancer evaluation of alkynylated pyrrole derivatives

A series of alkynylated pyrrole derivatives were meticulously designed, drawing inspiration from the structure of 3-alkynylpyrrole-2,4-dicarboxylates, which were synthesized via a cyclization process involving methylene isocyanides and propiolaldehydes under mild conditions. These derivatives were subsequently subjected to evaluation for their anticancer properties against a panel of cell lines, including U251, A549, 769-P, HepG2, and HCT-116. According to the detailed analysis of structure-activity relationship, compound 12l emerged as the most promising molecule, with IC50 values of 2.29 ± 0.18 and 3.49 ± 0.30 μM toward U251 and A549 cells, respectively. Subsequent mechanistic investigations revealed that compound 12l exerts its effects by arresting the cell cycle in the G0/G1 phase and inducing apoptosis specifically in A549 cells. These innovative alkynylated pyrrole derivatives hold the potential to serve as a valuable template for the discovery of novel anticancer molecules.

Identification of 3-(5-cyano-6-oxo-pyridin-2-yl)benzenesulfonamides as novel anticancer agents endowed with EGFR inhibitory activity

New 5-cyano-6-oxo-pyridine-based sulfonamides (6a-m and 8a-d) were designed and synthesized to potentially inhibit both the epidermal growth factor receptor (EGFR) and carbonic anhydrase (CA), with anticancer properties. First, the in vitro anticancer activity of each target substance was tested using Henrietta Lacks cancer cell line and M.D. anderson metastasis breast cancer cell line cells. Then, the possible CA inhibition against the human CA isoforms I, II, and IX was investigated, together with the EGFR inhibitory activity, with the most powerful derivatives. The neighboring methoxy group may have had a steric effect on the target sulfonamides, which prevented them from effectively inhibiting the CA isoforms while effectively inhibiting the EGFR. The effects of the 5-cyanopyridine derivatives 6e and 6l on cell-cycle disruption and the apoptotic potential were then investigated. To investigate the binding mechanism and stability of the target molecules, thorough molecular modeling assessments, including docking and dynamic simulation, were performed.

Discovery of novel potent PI3K/mTOR dual-target inhibitors based on scaffold hopping: Design, synthesis, and antiproliferative activity

The PI3K/AKT/mTOR pathway is one of the most common dysregulated signaling cascade responses in human cancers, playing a crucial role in cell proliferation and angiogenesis. Therefore, the development of anticancer drugs targeting the PI3K and mTOR pathways has become a research hotspot in cancer treatment. In this study, the PI3K selective inhibitor GDC-0941 was selected as a lead compound, and 28 thiophenyl-triazine derivatives with aromatic urea structures were synthesized based on scaffold hopping, serving as a novel class of PI3K/mTOR dual inhibitors. The most promising compound Y-2 was obtained through antiproliferative activity evaluation, kinase inhibition, and toxicity assays. The results showed that Y-2 demonstrated potential inhibitory effects on both PI3K kinase and mTOR kinase, with IC50 values of 171.4 and 10.2 nM, respectively. The inhibitory effect of Y-2 on mTOR kinase was 52 times greater than that of the positive drug GDC-0941. Subsequently, the antitumor activity of Y-2 was verified through pharmacological experiments such as AO staining, cell apoptosis, scratch assays, and cell colony formation. The antitumor mechanism of Y-2 was further investigated through JC-1 experiments, real-time quantitative PCR, and Western blot analysis. Based on the above experiments, Y-2 can be identified as a potent PI3K/mTOR dual inhibitor for cancer treatment.

Recent biological applications of heterocyclic hybrids containing s-triazine scaffold

s-Triazine possesses an auspicious status in the field of drug discovery and development owing to its presence in many naturally occurring compounds as well as commercially available drugs like enasidenib, gedatolisib, bimiralisib, atrazine, indaziflam, and triaziflam. Easy, cost-effective, and efficient access to its derivatives in addition to their splendid biological activities such as anticancer, anti-inflammatory, antiviral, anticonvulsant, anti-tubercular, antidiabetic, antimicrobial, makes it an attractive heterocyclic nucleus in the field of medicinal chemistry. Other than the direct access of its derivatives from simple commercially available starting materials like amidine, the s-triazine derivatives have also been obtained starting from an inexpensive commercially available 2,4,6-trichloro-1,3,5-triazine (TCT) commonly known as cyanuric chloride. Owing to the high reactivity and the possibility of sequential substitution of TCT, a variety of biologically active heterocyclic scaffolds have been installed on this nucleus in order to have more potent compounds. These s-triazine-based heterocyclic hybrids have been reported to show enhanced biological activities in recent years. Therefore, it is important to summarize and highlight recent examples of these hybrids which is imperative to attract the attention of the drug development community.

Antitumor Activity of s-Triazine Derivatives: A Systematic Review

1,3,5-triazine derivatives, also called s-triazines, are a series of containing-nitrogen heterocyclic compounds that play an important role in anticancer drug design and development. To date, three s-triazine derivatives, including altretamine, gedatolisib, and enasidenib, have already been approved for refractory ovarian cancer, metastatic breast cancer, and leukemia therapy, respectively, demonstrating that the s-triazine core is a useful scaffold for the discovery of novel anticancer drugs. In this review, we mainly focus on s-triazines targeting topoisomerases, tyrosine kinases, phosphoinositide 3-kinases, NADP+-dependent isocitrate dehydrogenases, and cyclin-dependent kinases in diverse signaling pathways, which have been extensively studied. The medicinal chemistry of s-triazine derivatives as anticancer agents was summarized, including discovery, structure optimization, and biological applications. This review will provide a reference to inspire new and original discoveries.