Anti-Cancer Agents in Medicinal Chemistry (Formerly Current Medicinal Chemistry - Anti-Cancer Agents) - Volume 23, Issue 9, 2023

CYP1B1 plays an essential role in cancer's pathogenesis since it activates procarcinogens. Significantly, this enzyme catalyzes the hydroxylation of 17β-estradiol, leading to carcinogenic metabolites involved in carcinogenesis and cancer progression. Therefore, the inhibition of CYP1B1 activity is considered a therapeutic target for chemotherapy. In addition, CYP1B1 is overexpressed in hormone-dependent cancer cells and could be related to resistance to anticancer drugs. However, the activity of CYP1B1 in the tumor microenvironment can metabolize and activate prodrugs in cancer cells, providing more selectivity and being useful for chemoprevention or chemotherapy strategies. Furthermore, due to its importance in anticancer drug design, recent studies have reported using computational methods to understand the intermolecular interactions between possible ligands and CYP1B1. Therefore, in this perspective, we highlight recent findings in developing CYP1B1 inhibitors (flavonoids, trans-stilbenes, estradiol derivatives, and carbazoles) and CYP1B1-activated prodrugs (a chalcone DMU-135 and an oxime DMAKO-20). Finally, we have analyzed their possible molecular interactions with this enzymatic target by molecular docking, which can help to design new active substances.

Background: Bakuchiol is a monoterpene phenol isolated from the seeds of Psoralea corylifolia Linn. It is used traditionally in Indian and Chinese medicine and has been reported to possess extensive pharmacological potential against a variety of ailments. A recent study enumerates the anticancer potential of bakuchiol. Objective: The objective of the present review study is to explore the anticancer potential of bakuchiol which provides insight into the design and develop novel molecular entities against various disorders. Methods: Current prose and patents emphasizing the anticancer potential of bakuchiol have been identified and reviewed with particular emphasis on their scientific impact and novelty. An extensive literature survey was performed and compiled via the search engine, PubMed, Science Direct, and from many reputed foundations. Results: The study's findings suggested and verified the anticancer potential that Psoralea and bakuchiol against a variety of cancer. Both Psoralea and bakuchiol also portrayed synergistic or potentiating effects when given in combination with other anticancer drugs or natural compounds. Conclusion: Altogether, the promising anticancer potential of bakuchiol may open new probes for therapeutic invention in various types of tumors. Thus, the present review gives the erudition of bakuchiol and Psoralea as anticancer which paves the way for further work in exploring their potential.

Cancer drug resistance has always been a serious issue regarding cancer research and therapy. Different cancers undergo different mutations, which may cause suppression of tumor suppressor genes, inhibition of apoptosis, stimulation of drug resistance mediators, and exhaustion of the immune system. The modulation of pro-death and survival-related mediators is an intriguing strategy for cancer therapy. Several nature-derived molecules, e.g., quercetin, have shown interesting properties against cancer through the modulation of apoptosis and autophagy mediators. Such molecules, e.g., quercetin, have been shown to stimulate apoptosis and other types of cell death pathways in cancers via the modulation of ROS metabolism. Quercetin may affect immune system function and trigger the expression and activity of tumor suppressor genes. Furthermore, it may suppress certain multidrug resistance mechanisms in cancer cells. This paper aims to review the effects of quercetin on various cell death mechanisms such as apoptosis, autophagic cell death, senescence, ferroptosis, and others.

PI3K is an important anticancer target as it controls cellular functions such as growth, transformation, proliferation, motility and differentiation. Plasma cell cancer (multiple myeloma) occurs more than 10% among all haematological malignancies and accounts for 2% of all cancer-related deaths each year, it is mainly regulated by PI3K/AKT signaling cascade. Quinazoline derivatives have been reported as promising PI3K inhibitors. Lapatinib, afatinib, gefitinib, erlotinib, idelalisib and copanlisib are quinazoline-based, FDA-approved PI3K inhibitors, while compounds like NVPBYL719, GDC-0032, AZD8186, AZD-6482, etc. are under different stages of clinical trials. In light of the above-mentioned facts, in the present study, we have reported different synthetic approaches, mechanisms of anticancer action, and structure-activity relationship analysis of reported quinazoline derivatives as PI3K inhibitors to help researchers working in the field in designing better and isoform-selective PI3K inhibitors.

Background: Somatostatin analogs (SSTAs) are versatile drugs that target a group of proteins known as somatostatin receptors. SSTAs are used for the treatment and PET-molecular imaging of Neuro Endocrine Tumors (NET), for they are labeled with the radionuclide ¹⁸F, a positron emitter radionuclide. Objective: The aim of this work was to theoretically study the binding interactions of SSTA labeled with ¹⁸F (half-life of 109.7 min) and somatostatin receptor subtype 2. As the labeling of SSTA with ¹⁸F required the use of a prosthetic group, a hydrophilicity enhancer, and a linker, the influence of these traits on the interactions of ¹⁸F-SSTA with the SSTR-2 binding site was studied. Methods: The binding modes of ¹⁸F-labeled analogues with SSTR-2 were studied by using protein homology modelling, non-equilibrium molecular dynamics, and molecular docking calculations, by means of three docking software: MVD, MOE, and VINA. Results: The results showed the main role of Asp122, Asn276, Phe272 and Phe294 from the SSTR-2 binding site, which form interactions with residues Lys, Trp, Tyr, and Thr from ¹⁸F-labeled somatostatin analogues. Conclusion: The interaction between Lys (from 18F-SSTA) and Asp122 (from SSTR-2) was identified as the most energetic and considered the one that drives the binding between ¹⁸F-SSTA and SSTR-2 (the anchor interaction). Despite the presence of prosthetic groups, linkers, and hydrophilicity enhancers, all the studied ¹⁸F-SSTA formed the anchor interaction. The trend in the results agreed with the experimental reports, identifying the main role of Asp122 in the binding of somatostatin-14 to SSTR-2.

Background: Colorectal cancer (CRC) is the third most common cancer worldwide. Current treatments, including surgery, radiotherapy, and chemotherapy, are limited by severe side effects and the development of resistance. Objective: Therefore, it is important to find additional therapies to combat the problem. Ginsenoside Rb1 is the main active ingredient of ginseng, which is a well-known herb in traditional Chinese medicine. Ginsenoside is reported to play an important role in the prevention and treatment of cancer. Methods: We established Azoxymethane (AOM)/Dextran sodium sulfate (DSS) colon cancer model based on inflammation, observed the beneficial effect of ginsenoside Rb1, and detected the changes in gut microbiota. Results: Our experimental results showed that ginsenoside Rb1 significantly reduced the levels of TNF-α, IL-6, IL- 17A, IL-33, IL-1β, and IL-22, increased the level of IL-10, and also changed the gut microbiota composition. These results suggested that ginsenoside Rb1 can be used to prevent inflammation-associated CRC development and may provide an effective therapeutic strategy for CRC by relieving chronic inflammation and restoring the gut microenvironment in the AOM/DSS-induced model of colitis-associated colorectal cancer in mice. Conclusion: Ginsenoside Rb1 significantly attenuated AOM/DSS-induced colon carcinogenesis.

Background and Objective: All-trans retinoic acid (ATRA) is only effective in acute promyelocytic leukemia (APL), but not in other subtype of acute myeloid leukemia (AML). Salinomycin targets tumor cells rather than non-tumorigenic cells, and WNT/β-catenin pathway inhibition is one of the mechanisms of its anti-tumor activity. There is a crosstalk between RA and WNT/β-catenin pathway. Here, we investigate the effect of the combination of salinomycin and ATRA (S+RA) in non-APL AML cells. Methods: Apoptosis was evaluated by cell viability and Annexin-V assay. Cell differentiation was analyzed by CD11c expression and morphology. To explore the underlying mechanisms, Western blot analysis and mitochondrial transmembrane potentials (ΔΨm) were used. Results & Discussion: S+RA induced differentiation and apoptosis in AML cell lines and AML primary cells. S+RA inhibited the β-catenin signal pathway as determined by the decreased protein levels of β-catenin, the low-density lipoprotein receptor-related proteins 6 (LRP6), and its downstream proteins such as survivin, c-Myc, caspase-3/7, cdc25A and cyclinD1 and reduced phosphorylation level of GSK3β S9. S+RA also increased the protein levels of CCAAT/enhancer-binding proteins (C/EBPs) and PU.1 and collapsed Δψm. The above molecular and cellular changes induced by S+RA were inhibited by β-catenin specific activator and promoted by β-catenin specific inhibitor. Conclusion: S+RA induced differentiation by β-catenin-inhibition-mediated up-regulation of C/EBPs and PU.1 and suppression of c-Myc. S+RA triggered apoptosis through β-catenin-inhibition-regulated ΔΨm collapse and caspase-3/7 activation. Taken together, our findings may provide novel therapeutic strategies for AML patients by targeting the WNT/β-catenin pathway.

Background: Targeting mutated isocitrate dehydrogenase 1 (mIDH1) is one of the key therapeutic strategies for the treatment of glioma. Few inhibitors, such as ivosidenib and vorasidenib, have been identified as selective inhibitors of mIDH1. However, dose-dependent toxicity and limited brain penetration of the blood-brain barrier remain the major limitations of the treatment procedures using these inhibitors. Objective: In the present study, computational drug repurposing strategies were employed to identify potent mIDH1- specific inhibitors from the 11,808 small molecules listed in the DrugBank repository. Methods: Tanimoto coefficient (Tc) calculations were initially used to retrieve compounds with structurally similar scaffolds to ivosidenib. The resultant compounds were then subjected to molecular docking to discriminate the binders from the non-binders. The binding affinities and pharmacokinetic properties of the screened compounds were examined using prime Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) and QikProp algorithm, respectively. The conformational stability of these molecules was validated using 100 ns molecular dynamics simulation. Results: Together, these processes led to the identification of three-hit molecules, namely DB12001, DB08026, and DB03346, as potential inhibitors of the mIDH1 protein. Of note, the binding free energy calculations and MD simulation studies emphasized the greater binding affinity and structural stability of the hit compounds towards the mIDH1 protein. Conclusion: The collective evidence from our study indicates the activity of DB12001 against recurrent glioblastoma, which, in turn, highlights the accuracy of our adapted strategy. Hence, we hypothesize that the identified lead molecules could be translated for the development of mIDH1 inhibitors in the near future.