Anti-Cancer Agents in Medicinal Chemistry (Formerly Current Medicinal Chemistry - Anti-Cancer Agents) - Volume 21, Issue 17, 2021

Background: Tumors are still among the major challenges to human health. Tumor-targeted therapy is an effective way to treat tumors based on precise medical models. Sialic acid (SA) is overexpressed on the surface of tumor cells, and Phenyl Boric Acid (PBA) can specifically bind to SA. However, studies on the use of PBA in tumor-targeted therapy are few. Objective: To summarize and analyze the characteristics and influencing factors of tumor targeted therapy in recent years, and the influencing factors of phenyl boric acid modified polymers in tumor targeted therapy, such as hydrogen ion concentration (pH), Adenosine Triphosphate (ATP), and sugars. This paper describes the application of phenyl boric acid partially functionalized nano-polymers in various types of targeted tumors, such as breast cancer, lung adenocarcinoma, liver cancer, and so forth. In order to further improve the basic research and clinical workers' understanding of nano-preparations and tumor targeted therapy. At the same time, it is also expected to promote the development value of phenyl boric acid. Methods: The findings on tumor-targeted therapy and the role of partially functionalized polymers with PBA in different tumors at home and abroad has been analyzed and summarized in recent years. Results: Tumor-targeted therapy is a promising treatment for tumors. PBA promotes the treatment of tumors using SA, which is highly expressed on the surface of tumor cells. Conclusion: Tumor-targeted therapy has shown great prospects for clinical application in recent years. PBA is beneficial as a member of the drug loading system. Further studies are still needed to promote its development and application.

Background: The antimetabolite, 5-Fluorouracil (5-FU), is the only chemotherapeutic drug to significantly improve 12-month survival rates of patients with Colorectal Cancer (CRC). However, resistance to 5-FU is a major obstacle to effective treatment. The mechanism of 5-FU resistance has been discovered but is not fully known. Nuclear factor-erythroid 2-related factor 2 (Nrf2), a master regulator of cellular defense against oxidative and electrophilic stresses, is considered a major factor in 5-FU resistance. Objective: The current study was conducted to discuss the role and mechanisms of Nrf2 in 5-FU resistance and to search for medicines or compounds that can reverse Nrf2-mediated 5-FU resistance. Methods: Literature was obtained by defining specific search terms and searching several databases. Results: Previous study suggested that overactivation of Nrf2 contributed to 5-FU resistance by regulating many cytoprotective genes. Interestingly, several medicines and compounds can repress 5-FU resistance mediated of Nrf2. Conclusion: This review describes the major 5-FU-resistance mechanisms of Nrf2 and summarizes the medicines/ compounds that can overcome them.

MiRNAs that are characterized by small non-coding RNAs orchestrate the expression of important genes involved in cancer cell development processes, including apoptosis, proliferation, angiogenesis, metastasis, and drug resistance at the post-transcriptional level. Dysregulation of miR-9 in various cancers has been reported. Recently, miR-9 has been considered as a key miRNA in various malignancies. However, its importance in the pathogenesis of different neoplasms is not yet well defined. Accordingly, this study was conducted in order to clarify the potential roles of miR-9 in the development of various cancers, prognosis, and treatment approaches. We have shown that a large number of miR-9 targets play fundamental roles in carcinogenesis, and that is dysregulated in various cancer cells. Our findings werefound aberrant miR-9 expression in a majority of cancers. This review article generally emphasizesthe critical roles of miR-9 in cancer cell progression. Additionally, we intended to investigate the effects of down-regulation or up-regulation of miR-9 in different types of cancers. It is hoped that a good understanding of the regulatory roles of miR-9 in various cancers ishelpful for using miR-9 in clinical settings, including prognosis, diagnosis, and miRNA-based target therapy.

Hypoxia pathway and aberrant miRNA expression profile play crucial roles in the development of various cancers. Recent studies have emphasized that there are many collaborations in this cases because both of them are involved in cancer cell processes, including differentiation, metastasis, and cell proliferation and signaling pathways. Further studies have elucidated that miRNAs affect the hypoxia route, and more interestingly, the hypoxia pathway also affects miRNAs expression profile. The literature review summarizes the fundamental roles of hypoxia-related miRNAs in different cancers. The mutual interactions between miRNAs and hypoxia are a new layer of complexity in cancer hypoxia, which might be helpful in controlling cancer progression. It is also possible that the hypoxia pathway is initiated by miRNAs. In contrast, the hypoxia pathway regulates the expression of a large group of miRNAs. In this review for the first time, we discussed the significant interactions between hypoxia and miRNAs in order to determine new perspectives for new therapeutic aims in the field of cancer.

The resistance to therapy of cancer cells is a challenge for achieving an appropriate therapeutic outcome. Cancer (stem) cells possess several mechanisms for increasing their survival following exposure to toxic agents such as chemotherapy drugs, radiation, as well as immunotherapy. Evidences show that apoptosis plays a key role in the response of cancer (stem) cells and their multi-drug resistance. Modulation of both intrinsic and extrinsic pathways of apoptosis can increase the efficiency of tumor response and amplify the therapeutic effects of radiotherapy, chemotherapy, targeted therapy, and also immunotherapy. To date, several agents, as adjuvant, have been proposed to overcome the resistance of cancer cells to apoptosis. Natural products are interesting because of the low toxicity on normal tissues. Resveratrol is a natural herbal agent that has shown interesting anti-cancer properties. It has been shown to kill cancer cells selectively while protecting normal cells. Resveratrol can augment reduction/oxidation (redox) reactions, thus increases the production of ceramide and the expression of apoptosis receptors, such as Fas Ligand (FasL). Resveratrol also triggers some pathways which induce the mitochondrial pathway of apoptosis. On the other hand, resveratrol has an inhibitory effect on antiapoptotic mediators, such as Nuclear Factor Κ B (NF-ΚB), Cyclooxygenase-2 (COX-2), Phosphatidylinositol 3– Kinase (PI3K), and mTOR. In this review, we explain the modulatory effects of resveratrol on apoptosis, which can augment the therapeutic efficiency of anti-cancer drugs or radiotherapy.

Background: Prostate cancer is the most common visceral neoplasia in men and frequently presents chemotherapy resistance. In this context, lemongrass (Cymbopogon citratus (D.C.) Stapf) has been studied since it presents many important biological activities, such as anticancer. Objective: We investigated the antitumor effect of lemongrass and in chemotherapy activity using prostate cancer cells line (DU-145). Methods: DU-145 cells were exposed to different concentrations of aqueous extract of lemongrass (30; 100; 300; 500 and 1000 μg/mL), isolated and in combination with docetaxel, during 24 and 72 hours. After, cell viability and proliferation, oxidative metabolism, colony formation and cell cycle analyses were performed. Also, we exposed the African green monkey kidney cell line (VERO) to the same lemongrass concentrations to investigate a possible toxicity of this extract. Results: Our findings suggested that lemongrass presented an antitumor effect and improved docetaxel chemotherapy activity by decreasing cell viability and proliferation as well as colony formation. Moreover, we found an oxidative stress increased and cell cycle arresting in G0 /G1 phase. In addition, this extract presented selectivity action for cancer cells, since it did not cause cytotoxicity in normal cells, ensuring non-toxic therapeutic concentrations. Conclusion: Lemongrass is a promising medicinal plant that could be used during chemotherapeutic treatment, in order to potentiate the antitumor response and decrease the resistance of prostate cancer.

Background: Coumarin structures were widely employed in anti-cancer drug design. Herein we focused on the modifications of C4 and C6 positions on coumarin scaffold to get novel anti-cancer agents. Objective: The objective of the current work was the synthesis and biological evaluation of a series of 4, 6-coumarin derivatives to get novel anticancer agents. Methods: Thirty-seven coumarin derivatives were designed and synthesized, the antiproliferative activity of the compounds was evaluated against human cancer cell lines and non-cancerous cells by MTT assay. The bioactivities and underlying mechanisms of active molecules were studied and the ADMET characters were predicted. Results: Among the compounds, 4-p-hydroxy phenol-6-pinacol borane coumarin (25) exhibited a promising anti- cancer activity to cancer cell lines in a dose-dependent manner and the toxicity to normal cells was low. The mechanism of action was observed by inducing G2/M phase arrest and apoptosis which was further confirmed via western blot. In silico ADMET prediction revealed that compound 25 is a drug-like small molecule with a favorable safety profile. Conclusion: The findings in this work may give vital information for further development of 6-pinacol borane coumarin derivatives as novel anti-cancer agents.

Background: The Androgen Receptor (AR) signaling functionis a critical driving force for the progression of Prostate Cancer (PCa) to bring about anti-prostate cancer agents, and AR has been proved to be an effective therapeutic target even for Castration-Resistant Prostate Cancer (CRPC). Objective: In order to discover novel anti-prostate cancer agents, we performed structural modifications based on the lead compounds T3 and 10e. Methods: A set of 1-methyl- 1H-pyrazole-5-carboxamide derivatives were synthesized and evaluated for their inhibitory activities against both expressions of Prostate-Specific Antigen (PSA) and growth of PCa cell lines. Results: Compound H24 was found to be able to completely block PSA expression at 10μM, and showed prominent antiproliferative activity in both the LNCaP cell line (GI50 = 7.73μM) and PC-3 cell line (GI50 = 7.07μM). Conclusion: These preliminary data supported a further evaluation of compound H24 as a potential agent to treat prostate cancer.

Background: Pyrvinium Pamoate (PP) is an old drug approved by the FDA for the treatment of pinworm infections. Recently, it has been introduced as an anti-tumor agent, however, low aqueous solubility severely limits its potential effects. In this study, we developed a liposomal formulation of pyrvinium pamoate to investigate its in vitro cytotoxicity and in vivo efficacy against melanoma cells. Materials & Methods: As drug carriers, liposomes were fabricated using the thin-film method. PP was encapsulated within the liposomes using a remote loading method. We evaluated the morphology, particle size, and Zeta potential of the liposomes. Additionally, High-Performance Liquid Chromatography (HPLC) was employed for qualitative and quantitative analysis. Then we investigated our liposomal PP for its in vitro cytotoxicity as well as the tumor growth inhibition in C57BL/6 mice bearing B16F0 melanoma tumors. Results: Based on the analytical result, the liposomal drug delivery system is a homogeneous and stable colloidal suspension of PP particles. The images of Atomic force microscopy and particle size data showed that all the prepared nanocarriers were spherical with a diameter of approximately 101 nm. According to both in vitro and in vivo studies, nanoliposomal PP exhibited an improved anti-proliferative potential against B16F10 melanoma tumor compared to free PP. Conclusion: Liposomal encapsulation improves the water solubility of PP and enhances its anti-cancer activity.

Background: In previous studies, we provided evidence suggesting the involvement of γ-synuclein in growth, invasion, and metastasis of colon cancer cells in vitro and in vivo. Among γ-synuclein downstream genes, the microtubule-associated protein 1 Light Chain 3 (LC3), an autophagy gene, was screened by gene expression profile chip analysis. Objective: We planned to investigate the functional effects of γ-synuclein on autophagy induced by ER stress in colon cancer cells. Methods: We investigated the functional effects of γ-synuclein on autophagy and apoptosis induced by Thapsigargin (TG), ER stress-inducing agent, in colon cancer cell lines using immunofluorescence staining, RT-PCR, western blot, CCK8 test, flow cytometry analysis, and transmission electron microscopy. To further determine how γ-synuclein regulated autophagy and apoptosis, PD98059 (ERK inhibitor), SP600125 (ERK inhibitor), anisomycin (JNK activator), and c-Jun siRNA were used respectively in γ-synuclein siRNA transfected HCT116 cells. Then, autophagy proteins, apoptosis proteins, and pathway proteins were detected by western blot analysis. The expression of autophagy genes was assessed by RT-PCR. Results: Our data showed that ER stress-induced colon cancer cells autophagy mainly in the early stage (0-24h) and apoptosis mainly in the late stage (24-48h). ER stress up-regulated γ-synuclein gene and protein expression in colon cancer cells, accompanied by autophagy. γ-synuclein protected HCT116 cells by enhancing autophagy in the early stage (0-24h) through activation of ERK and JNK pathway and inhibiting apoptosis in the late stage (24-48h) through inhibition of the JNK pathway. γ-synuclein could promote autophagy via the JNK pathway activation of ATG genes, LC3, Beclin 1, and ATG7. γ-synuclein may play a role in the transition between autophagy and apoptosis in our model. Conclusion: Overall, we provided the first experimental evidence to show that γ-synuclein may play an important role in autophagy that protects colon cancer cells from ER stress. Therefore, our data suggest a new molecular mechanism for γ-synuclein-mediated CRC progression.

Background: Thiazolidine-4-one is a promising class of heterocyclic compounds with interesting pharmacological and biological activities, such as anticancer and antibacterial. Therefore, many researchers have synthesized thiazolidine-4-ones and evaluated their biological potential for developing new drugs. Objective: In this study, two novel thiazolidine-4-one derivatives (T1 and T2) were synthesized and evaluated for their antibacterial activity toward Staphylococcus aureus, Escherichia coli, and Proteus mirabilis. Also, the cytotoxic activities of compounds T1 and T2 were estimated against MCF-7 (HER2+, ER+, and ER+) and MDAMB- 231 (triple-negative) human breast cancer cell lines. The chemical structures of the compounds T1 and T2 were proven using spectral techniques (FT-IR, ¹HNMR, and ¹³CNMR) and CHN elemental analysis. Methods: The synthesis of thiazolidine-4-one compounds was performed in two steps. The first step consisted of the formation of Schiff bases S1 and S2. In the second step, the synthesized Schiff bases were reacted with thioglycolic acid to prepare thiazolidine-4-one compounds. Hemolysis assay, molecular docking, cytotoxicity activity (MTT assay), and antibacterial activity (disc diffusion assay) were studied. Results: The hemolysis study demonstrated that the hemolytic ratio of compounds T1 and T2 at (1, 2, and 3) mg/ml was less than 4%. MTT assay showed that 100 μg/ml of compounds T1 and T2 diminish the MCF-7 cell growth up to 80.05 ± 1.72 and 69.85 ± 3.26 respectively after 72hr., while the same concentration of compounds T1 and T2 reduces the MDA-MB-231 cell growth up 70.28 ± 2.31 and 57.15 ± 1.49, respectively. The inhibition zones of T1 and T2 were 12 mm at 50 mg/ml and 10 mm at 5 mg/ml in E. coli bacteria. Furthermore, a docking study was carried out to investigate the affinity and binding mode of compounds T1 and T2 towards the ERα, VEGF, and HER2 protein receptors in breast cancer cells. Data obtained from the docking study were exactly identical to that obtained from in vitro cytotoxicity assay. Conclusion: The results proved that T1 is an optimal anticancer agent toward breast cancer cells and the hemolysis study indicates the use of safety inside the body for compound T1. Synthesized compound T1 was most effective against MCF-7 cells compared to MDA-MB-231 cells and more effective than the reference drug tamoxifen in breast cell lines. The high cytotoxicity of T1 on the growth of MCF128;7 cells because T1 binds with a high degree of affinity to the estrogen and HER2 receptors, which in turn inhibits cell proliferation and induces apoptosis.

Background: The benzimidazole and their derivatives have rich biological relevance with respect to available natural amino acids and their role in protein folding and quaternary conformations. Thus the ligand trizbenzim and their Cu(II) and Zn(II) metal complexes were prepared to induce G-quadruplex conformation even under no-salt conditions with remarkable anticancer activities. Methods: The ligand N,N',N''-Tris-(1H-benzoimidazol-2-ylmethyl)-[1,3,5]triazine-2,4,6-triamine ( trizbenzim) and its Cu and Zn complexes (Cu-trizbenzim, Zn-trizbenzim) were synthesized and characterized by IR, NMR, and MALDI-TOF techniques. The pure ligand and its complexes interacted with human telomere DNA sequence d(TTAGGG), HTelo8and HTelo20and the interactions were followed by circular dichroism spectroscopy, FID assay, and molecular docking techniques. The compounds were tested for anticancer activity towards selected cell lines. Results: All the three compounds stabilized the HTelo8 and HTelo20 in parallel and antiparallel G-quadruplex conformations with salt conditions. Under no-salt conditions, the compounds induce and stabilize the G-quadruplex conformation in antiparallel topology selectively. The pure ligand, Cu-trizbenzim, and Zn-trizbenzim were involved in partial or classical intercalation and some backbone interactions on the strand. The FID assay using thiazole orange intercalator supports the proposed intercalation mode of binding for the three compounds, especially for the pure ligand and the Cu-complex. The MOE docking experiments using X-ray and NMR derived G-quadruplex models with the title compounds extensively support the G-quadruplex induction and stabilization of the telomere sequence by these compounds. The guanines bases involved in the G-tetrad formation interact well with the triazine and the benzimidazole part of the ligand through strong π-π interactions. The primary mode of binding is described as end stacking and intercalation of the compounds to the G-quadruplex structures. The Cu-trizbenzim exhibited more anticancer property in comparison to the pure ligand and the Zntrizbenzim complex. The IC50 values were in the nanomolar range from 50 to 150nM in concentration. Conclusion: This novel self-induction of G-quadruplex is novel without the presence of alkali metal ions.

Background: We previously synthesized two DNA intercalative Pyrimido[4’,5’:4,5]thieno(2,3-b) quinolines (PTQ), 9-hydroxy-4-(3-diethylaminopropylamino)pyrimido[4’,5’:4,5]thieno(2,3-b) quinolines (Hydroxy- DPTQ) and 8-methoxy-4-(3-diethylaminopropylamino) pyrimido[4’,5’:4,5]thieno(2,3-b) quinolines (Methoxy-DPTQ), and reported their cytotoxicity against cancer cell lines. Methods: In the present study, we sought to analyze the antitumor activity of Hydroxy-DPTQ and Methoxy-DPTQ on Ehrlich’s ascites carcinoma in vivo models, along with other pharmacological activities and toxicity. Results: In this study, both the test molecules studied possess potent in vivo antitumor activity without any hematological, biochemical or nephrotoxicity. Significant tumor regression was observed after treatment with both the test molecules, which is suggested by the decrease in the bodyweight of tumour-bearing mice. Mean survival time of mice with tumor was increased from 16 days to 25 and 29 days after 40 and 80 mg/kg Hydroxy- DPTQ treatment, respectively, with a similar result for Methoxy-DPTQ. A dose-dependent increase in lifespan up to 80-85% was also displayed by both Hydroxy-DPTQ and Methoxy-DPTQ. Reduction in the tumor volume of mice, upon treatment with molecules also confirmed their antitumor activity. These molecules also exhibited pharmacological activities such as antioxidant, anti-inflammatory and analgesic activities. Administration of Hydroxy-DPTQ and Methoxy-DPTQ not only reduced the level of lipid peroxidation in tumor bearing mice but also restored the superoxide dismutase, glutathione, and catalase levels to normal, substantiating the antioxidant property. Also, treatment of Hydroxy-DPTQ and Methoxy-DPTQ inhibited the pain to approximately 60-80% and 19-33%, respectively. Further, the treatment with Hydroxy-DPTQ and Methoxy-DPTQ reversed the abnormality in the RBC, WBC and haemoglobin levels, and gentamicin induced nephrotoxicity. Conclusion: Hydroxy-DPTQ and Methoxy-DPTQ are good antitumor molecules with pharmacological properties.

Background: Recent advances in nanotechnology have led to the use of nanomaterials in the diagnosis of cancer by imaging techniques. Objective: This study aimed to synthesize fluorescein-conjugated gold nanoparticles and study the parameters affecting the loading of fluorescein on synthesized coated gold nanoparticles with the ability to be used in medical diagnostic methods. Methods: The synthesized gold nanoparticles were functionalized with polyethylene glycol. Then, these particles were conjugated with fluorescein under different conditions. To investigate the optical and structural features as well as the factors affecting the loading, the nanoparticles were evaluated by ultraviolet-visible, fluorescence and FT-IR spectrophotometer, fluorescence spectrophotometer, transmission electron microscopy, dynamic light scattering, and zeta potential measuring device. Also, the use of these particles in cancer diagnosis on the skin melanoma cell (B16F10) was examined using a fluorescence microscope. Results: PEG-coated spherical gold nanoparticles were synthesized as a carrier for the fluorescein dye detector. The coating agent concentration, incubation time, temperature, and pH of the medium affected the loading efficiency of fluorescein on the nanoparticles. Also, optimal conditions for use in the diagnostic applications were investigated. Ten micromolar of the sample were selected for cell imaging studies. The fluorescence signal of B16F10 cells containing nanoparticles was relatively strong, indicating the amount of nanoparticles uptaken by the cells. Conclusion: The results showed that by designing fluorescent gold nanoparticles with fluorescein as fluorescent detectors and considering their diagnostic importance, an efficient way to diagnose incurable diseases can be found.

Background: Recently, products of Multi-Component Reactions (MCR’s) acquired special attention due to their wide range of pharmacological activities especially therapeutic activities. In the market it was found that many pharmacological drugs containing the pyran and pyridine nucleus that were produced through MCR’s were found. Objective: This work aims to synthesize target molecules not only possess anti-tumour activities but also c-Met and prostate cancer inhibitors. The target molecules were obtained starting from cyclohexan-1,3-dione through its multi-component reactions to produce anticancer target molecules. Methods: Cyclohexane-1,3-dione underwent different multi-component reactions to produce fused pyran, pyridine and thiophene derivatives. The anti-proliferative activity of the newly synthesized compounds among the synthesized compounds toward the six cancer cell lines, namely A549, H460, HT-29, MKN-45, U87MG, and SMMC-7721 was studied. In addition, inhibitions toward c-Met kinase and prostate cancer cell line were studied. Antitumor evaluations toward seventeen cancer cell lines subpanel, for certain compounds, were also demonstrated according to the diseases. Pim-1 kinase inhibitions of the most active compounds were also measured. Results: Anti-proliferative evaluations, c-Met and Pim-1 kinase inhibitions were performed for most of the synthesized compounds where the varieties of substituent through the aryl ring and the heterocyclic ring afforded compounds with high activities. Conclusion: Compounds 4b, 6b, 8b, 9a, 11b, 12b, 17b, 18b, 19, 22c, 23b, 25b and 26b were the most cytotoxic compounds toward the six cancer cell lines. Inhibitions toward c-Met kinase and prostate cancer cells showed that the presence of the electronegative Cl group within the molecule were responsible for its high activity. In addition, inhibitions toward Pim-1 kinase exhibited that most of tested compounds showed high inhibitions.

Minor changes are required in the Funding information and the acknowledgement for the article entitled “Organosulphur Compounds Induce Apoptosis and Cell Cycle Arrest in Cervical Cancer Cells via Downregulation of HPV E6 and E7 Oncogenes” in “Anti-Cancer Agents in Medicinal Chemistry, 2021, Vol. 21, No. 3, pp. 393-405.” The correct Funding information and Acknowledgement is given below: FUNDING: This project was funded by the Council of Science and Technology (CST), Lucknow, Uttar Pradesh, India (Sanction No. CST/374). The financial support during this research was also provided by the Deanship of Scientific Research, King Khalid University, Abha, Saudia Arabia through the General Research Project under grant number R.G.P. 01/48/42. ACKNOWLEDGEMENT: IAA is greatly thankful to the Council of Science and Technology (CST), Uttar Pradesh, India, for providing him project as a Principal Investigator. Authors would also like to acknowledge the support of the King Khalid University through the General Research Project under grant number R.G.P. 01/48/42. under the Deanship of Scientific Research, King Khalid University, Abha, Saudia Arabia