Anti-Cancer Agents in Medicinal Chemistry (Formerly Current Medicinal Chemistry - Anti-Cancer Agents) - Volume 23, Issue 17, 2023

Background: Intermittent fasting (IF) diets have been popular since the last few decades because of their provable clinical efficiency on weight control of the subjects. These diet types are generally safe, resulting in health promoting effects against several human diseases like cardiovascular diseases, diabetes mellitus, neurogenerative disorders and cancer. Objective: To review whether IF can act against cancer development and progression, highlighting potential anticancer molecular mechanisms in clinical studies. Methods: Applied summarization of the available clinical studies investigating the effectiveness of IF against cancer development and progression and cancer-induced indicators. Scientific databases, e.g., PubMed, and Scopus, were comprehensively searched using relative words to identify in vivo and in vitro data, as well as clinical studies. Results: IF seems to exert health-promoting effects in cancer patients through induction of autophagy, which enhances the in vivo suppression of tumor development, by chemotherapy. IF provokes tumors to chemotherapy and defends the normal cells from its adverse side effects, increasing the immune response. In addition, it enhances the cytotoxic CD8(+) tumor-infiltrating lymphocytes and the bone marrow lymphoid progenitor cells, delaying the cancer progression. IF reduces oxidative stress via repression of translation and induces cellular apoptosis. Fasting exerts anti-aging properties modulating the secretion of IGF-1, IGFBP-1, glucose, and insulin while, at the same time, it integrates cell adaptive responses and activates cell signaling pathways which stimulates antioxidant defenses, DNA repairment, control of protein quality, mitochondrial synthesis while decreasing inflammation. Conclusion: IF appears to exert health promoting effects against cancer development and progression, suppressing several kinds of cancer. There are well-recognized and not well-recognized molecular processes accentuating its anticancer outcomes; however, well-designed clinical trials and further molecular studies are strongly recommended.

The proper course and reproducibility of diagnostic techniques depend on narrowly defined reaction conditions, including the reaction pH. Nevertheless, numerous assays are affected by an inaccurately defined reaction pH. Buffers are sometimes suggested for use outside their useful pH ranges, which complicates the reproducibility of results because the buffering capacity is insufficient to retain the disclosed pH. Here, we focus on the comet assay lysis buffer. Comet assay is broadly used for quantifying DNA breaks in eukaryotic cells. The most widespread comet assay protocols employ lysis of the cells before electrophoresis in a buffer containing Triton X-100, a high concentration of NaCl, sodium sarcosinate, EDTA, and Tris, with some modifications. However, nearly all researchers report that they use Tris buffer at pH 10, and some report the pH of the Tris additive alone. Alternatively, others report the pH of the final lysis buffer. However, the lysis solution used in the comet assay is buffered at a pH outside the useful range of Tris. Tris-based buffers have a useful pH range of 7.0 - 9.0. The buffer composed of 10 mM Tris has pKa 8.10 at 25°C and 8.69 at 4°C. The cell lysis conditions used in nearly all modifications of comet assay protocols remain imprecise and uncritically employed. Despite the pH of the lysis buffer likely has negligible effect on the detection of DNA breaks, precise lysis conditions are highly important for the use of comet assay in the detection of base modifications, which are often unstable and sensitive to pH.

Background: As a chemoprevention agent, crocin effectively decreases the risk of human cancers, including colorectal cancer (CRC). However, the mechanism underlying the anti-cancer effects of crocin is not entirely explained. Considering that in this study, we investigated the crocin effect on miR-143/145 and related signaling pathways in CRC cells. Methods: HCT-116 and HT-29 CRC cells were treated with different concentrations of crocin and then were subjected to MTT and qRT-PCR assays to investigate cell viability and miR-143/miR-145, KRAS, and RREB1 expression, respectively. Also, western blotting was performed to evaluate gene expression at protein levels. Results: Our results showed that treating CRC cells with crocin decreases cell viability by upregulating miR-143/145 expression and reducing KRAS and RREB1 expression dose-dependently. These effects on gene expression in CRC cells were reversed by removing crocin from the media after 48 h. Furthermore, western blotting results exhibited that crocin significantly reduced the protein expression of KRAS and RREB1. Also, it was found that treatment of CRC cells by crocin led to the inactivation of AKT by decreasing its phosphorylation. Conclusions: This study suggests that crocin may inhibit CRC cell proliferation by modulating KRAS, REEB1, and AKT signaling pathways mediated through miR-143/145 upregulation.

Background: Indazoles are known for their anti-cancer properties. Objective: The current investigation was on the synthesis and evaluation of novel indazole derivatives for their anticancer properties. Methods: A series of novel indazoles were synthesized and characterized by IR, NMR and LCMS. We performed cytotoxic studies for all synthesized compounds on different cell lines such as HeLa, MCF-7 and EAC using MTT assay. The lead compound was tested further for its anti-tumor and anti-angiogenic effect on EAT tumor model. Results: Amongst the series of compounds synthesized, compound KA8 showed potent antiproliferative effect against Hela, MCF-7 and EAC cell lines with IC50 values 10.4 to 11.5 and 13.5 μM respectively. In addition, our compound KA8 significantly decreased the cell viability, body weight, ascites volume and it also showed superior survival ability of mice compared to control groups. Furthermore, it suppressed the formation of neovasculature in the peritoneum of EAT-bearing mice. Conclusion: The findings reveal that the lead compound KA8 possesses potent anti-tumor and anti-angiogenic properties thereby promising it to be developed as a novel anticancer agent with further mechanistic studies.

Background: Quinazolinone scaffolds have drawn international attention due to their potent anticancer activity and therapeutic applications. Furthermore, Chalcone and Oxime are special chemical templates with a wide range of biological activities, including anti-cancer activity. As a result, the purpose of this research is to synthesize and develop a new series of 2-thioxo-3-substituted quinazolin-4-one/chalcone analogues and 2-thioxo-3-substituted quinazolin-4-one/oximes analogues in order to obtain a new cytotoxic agent that can target epidermal growth factor (EGFR) and/or V-Raf Murine Sarcoma Viral Oncogene Homolog B (BRAF^V600E) oncogene. Objective: All synthesised compounds were tested for anticancer activity against four human cancer cell lines. The new hybrids' potential anti-cancer mechanism was evaluated using EGFR and BRAF enzymatic tests. The most active molecules within the target enzyme's active site were studied using molecular docking. Apoptosis and cell cycle analysis were also investigated. Methods: The target compounds 7a-j (series I) are obtained in high yields by alkylation of 2-mercapto-3-ethyl-(3H)- quinazolin-4-one 3a with acylated chalcones 6a-j. Alkylation of compounds 3b-c with N-(4-acetylphenyl)-2- bromoacetamide 8, the corresponding ketones intermediates 9b-c was produced in high yields. Compounds 7a-j, 9b-c, and 10b-c were tested for their antiproliferative activity against four human cancer cell lines using the MTT assay and doxorubicin as a control drug. The EGFR and BRAF assay tests were used to assess the inhibitory potency against EGFR and BRAF. Results: Compounds 7c, 7d, 7f and 10c exhibited high proliferative activity and inhibited EGFR, which could serve as a potential target for antiproliferative activity. The most active hybrid, 7c, primarily caused cell cycle arrest in G0/G1 phase and S phase as well as cell apoptosis. Finally, the most active hybrids were docked well to the EGFR active site. Conclusion: 2-thioxo-3-substituted quinazolin-4-one/chalcone derivatives have significant apoptotic and antiproliferative properties.

Background: Glutaminase (GLS), the key enzyme involved in glutamine metabolism, has been identified as a critical player in tumor growth and progression. The GLS inhibitor CB-839 has entered several clinical trials against a variety of tumors. Objective: Our study aimed to investigate the role and underlying mechanism of GLS and its inhibitor CB-839 in nasopharyngeal carcinoma (NPC). Methods: The expression, downstream genes, and signaling pathways of GLS in NPC were determined by real-time polymerase chain reaction (RT-PCR), PCR array, western blotting (WB), and immunohistochemical staining (IHC), and the phenotype of GLS was confirmed by in vivo experiments of subcutaneous tumor formation in mice and in vitro experiments of functional biology, including Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, transwell migration, and Boyden invasion assay. Finally, it was also verified whether the treatment of NPC cells by GLS inhibitor CB-839 can change various biological functions and protein expression to achieve the purpose of blocking tumor progression. Results: GLS was remarkably overexpressed in NPC cells and tissues, predicting a poor overall survival of NPC patients. GLS promoted cell cycle, proliferation, colony formation, migratory, and invasive capacities by regulating Cyclin D2 (CCND2) via PI3K/AKT/mTOR pathway in NPC in vitro and in vivo. Notably, CB-839 showed an effective anti-NPC tumor effect by blocking the biological functions of the tumor. Conclusion: The first innovative proof is that GLS promotes cell proliferation by regulating CCND2 via PI3K/AKT/mTOR pathway in NPC, and GLS inhibitor CB-839 may serve as a new potential therapeutic target for NPC treatment.

Background: The development of chemotherapy resistance in prostate cancer (PCa) patients poses a significant obstacle to disease progression. Ribonucleotide reductase is a crucial enzyme for cell division and tumor growth. Triapine, an inhibitor of ribonucleotide reductase, has shown strong anti-tumor activity in various types of cancers. However, the effect of triapine on docetaxel-resistant (DR) human PCa cells has not been explored previously. Aim: This study aimed to examine the potential anti-proliferative effects of triapine in PC3-DR (docetaxel-resistant) cells. Methods: Cell viability was determined by the MTT test, and apoptosis and cell cycle progression were analyzed by image-based cytometer. mRNA and protein expression were assessed by RT-qPCR and western blot, respectively. Results: Triapine administration significantly reduced PC3 and PC3-DR cells' survival, while the cytotoxic effect was higher in PC3-DR cells. Cell death resulting from inhibition of ribonucleotide reductase was mediated by endoplasmic reticulum stress, induction of apoptosis, and cell cycle arrest. The findings were supported by the upregulation of caspases, Bax, Bak, P21, P27, P53, TNF-α, FAS, and FASL, and downregulation of Bcl2, Bcl-XL, cyclin-dependent kinase 2 (CDK2), CDK4, cyclins, and heat shock proteins expression. According to the data, the reduction of ABC transporter proteins and NF-ĸB expression may play a role in triapine-mediated cytotoxicity in docetaxel-resistant cells. Conclusion: Based on our findings, triapine emerges as a promising chemotherapeutic approach for combating docetaxel- resistant prostate cancer.

Background: Sintilimab (Sin) helps the body to restore the anti-tumor response of T lymphocytes. However, in clinical use, the treatment process is more complicated due to adverse effects and different dosing regimens. It is not clear whether prebiotics (PREB) have a potentiating effect on Sin for lung adenocarcinoma, and this study intends to investigate the inhibitory effect, safety and possible mechanism of Sin combined with PREB on lung adenocarcinoma from animal experiments. Methods: Lewis lung adenocarcinoma cells were inoculated into the right axilla of mice subcutaneously to prepare the Lewis lung cancer mouse model and treated in groups. The volume of transplanted tumors was measured, the histopathology of the liver and kidney of mice was observed by H staining, the levels of ALT, AST, UREA, CREA, WBC, RBC, and HGB in blood were analyzed biochemically; the ratio of T-cell subpopulations in blood, spleen, and bone marrow was detected by flow cytometry, the expression of PD-L1 in tumor tissue was detected by immunofluorescence staining, and 16S rRNA to analyze the diversity of fecal flora. Results: Sin inhibited tumor growth and regulated immune cell homeostasis in lung adenocarcinoma mice, but liver and kidney histopathology showed different degrees of damage after Sin treatment, while the addition of PREB reduced liver and kidney damage in lung adenocarcinoma mice and promoted Sin's regulation of immune cells. In addition, the beneficial effects of Sin were associated with changes in intestinal flora diversity. Conclusion: The mechanism by which Sintilimab combined with prebiotics inhibits tumor volume and regulates immune cell subpopulation balance in lung adenocarcinoma mice may be related to gut microbes.

Introduction: The marine environment is a rich source of biodiversity, with several of its inhabitants producing unique and physiologically active substances. The use of marine bacterial-derived chemicals over traditional pharmaceuticals is gaining traction due to their larger variety of targets and modes of action. To circumvent the drawbacks of current therapy options, researchers have looked to marine microbes for novel and effective anti-cancer compounds. In this study, we examine one of India's least-examined coastal areas in search of novel bacterial sources of anti-cancer chemicals. Method: Soil sediments from the Indian south coast region were collected and microbes were isolated using standard methods. The microorganisms were identified using 16s rRNA sequencing, and cytotoxic extracts were further examined using GC-MS. MTT, clonogenic, and spheroid tests assessed the extract's cytotoxicity and anti-tumor efficacy. Results: Our results indicated that the bacterial isolates with potent cytotoxic activity were Bacillus drentensis and Bacillus haikouensis and had 10 and 12 potent anti-cancer and other bioactive compounds. The extracts had an IC50 of 30.08 and 109.4 μg/ml in the HCT116 cell line, respectively, and strongly inhibited colony formation. The cell cycle analysis indicated that the extract induced cell death as indicated by the subG0 peak. We also showed that these methanolic extracts induced toxicity in a 3D spheroid model indicating a strong anti-tumor activity. Furthermore, we performed molecular docking for the compounds present in the extracts to VEGFR and nucleolin and found that ergostane had favorable binding energy only to VEGFR. Conclusion: The results indicate that the ME of B. drentensis and B. haikouensis contains potent anti-cancer compounds to exhibit cytotoxic and anti-tumor activity in colorectal cancer cells.