Anti-Cancer Agents in Medicinal Chemistry (Formerly Current Medicinal Chemistry - Anti-Cancer Agents) - Volume 20, Issue 8, 2020

Cancer management and/or treatment require a comprehensive understanding of the molecular and signaling pathways involved. Recently, much attention has been directed to these molecular and signaling pathways, and it has been suggested that a number of biomolecules/players involved in such pathways, such as PI3K/Akt, NF-ΚB, STAT, and Nrf2 contribute to the progression, invasion, proliferation, and metastasis of malignant cells. Synthetic anti-tumor agents and chemotherapeutic drugs have been a mainstay in cancer therapy and are widely used to suppress the progression and, hopefully, halt the proliferation of malignant cells. However, these agents have some undesirable side-effects and, therefore, naturally-occurring compounds with high potency and fewer side-effects are now of great interest. Osthole is a plant-derived chemical compound that can inhibit the proliferation of malignant cells and provide potent anti-cancer effects in various tissues. Therefore, in this review, we presented the main findings concerning the potential anti-tumor effects of osthole and its derivatives and described possible molecular mechanisms by which osthole may suppress malignant cell proliferation in different tissues.

Background: Compounds containing furo[3,2-b]pyridine framework have shown interesting pharmacological properties, including anticancer activities. Though these compounds are generally synthesized via the heteroannulation processes involving acetylenic derivatives, some of them are complex. Objective: The study aimed to explore a series of 2-substituted furo[3,2-b]pyridines for their cytotoxic properties against cancer cell lines in vitro. Methods: We developed a convenient synthesis of 2-substituted furo[3,2-b]pyridines via sequential (i) C-C coupling followed by (ii) C-O bond-forming reactions in a single pot. The reactions were performed under ultrasound irradiation in the presence of Pd/C as an inexpensive, stable and widely used catalyst. A range of 2- substituted furo[3,2-b]pyridines were synthesized via coupling of 3-chloro-2-hydroxy pyridine with terminal alkynes in the presence of 10% Pd/C-CuI-PPh3-Et3N in EtOH. The in vitro evaluation of all these compounds was carried out against MDA-MB-231 and MCF-7 cell lines and subsequently against SIRT1. Results: The furo[3,2-b]pyridine derivative 3b showed encouraging growth inhibition of both MDAMB-231 and MCF-7 cell lines and inhibition of SIRT1. The compound 3b also showed apoptosis-inducing potential when tested against MCF-7 cells. Conclusion: The Pd/C-Cu catalysis under ultrasound accomplished a one-pot and direct access to 2-substituted furo[3,2-b]pyridine derivatives, some of which showed anticancer properties.

Background: Colorectal Cancer (CRC) is one of the most common fatal diseases with high morbidity. Alteration of glucose metabolism is one of the hallmarks in the development of CRC. Glucose Transporter 1 (GLUT1) is a key rate-limiting protein in hyperactive glucose metabolism and up-regulated in CRC, however, the underlying mechanism of the altered metabolism in CRC is still unknown. Methods: In this study, immunohistochemical staining was used to evaluate the expression of GLUT1 and FOXM1 in 135 paired CRC and adjacent normal tissues. The association between the expression of GLUT1/FOXM1 and clinicopathological factors was determined and the correlation between GLUT1 and FOXM1 in CRC was investigated. Results: Our results revealed that regardless of tumor location, GLUT1 and FOXM1 were overexpressed in CRC tissues, especially in patients with positive lymph node metastasis and TNM stage III-IV. Furthermore, GLUT1 showed a significantly strong link with FOXM1 in CRC tissue. Conclusion: Overexpression of GLUT1 and FOXM1 may play critical roles in CRC leading to a poor prognosis.

Background & Purpose: In evaluating new drugs for the treatment of various types of cancer, investigations have been made to discover a variety of anti-tumor compounds with less side effects on normal cells. Investigations have shown that the heterodimers S100A8 and S100A9 inhibit the enzyme casein kinase 2 and then prevent the activation of the E7 oncoprotein. Therefore, the aim of this study was to evaluate the effect of calprotectin as an antitumor compound on the Nalm6 (B cell precursor leukemia cell line). Materials & Methods: Transformation of genes encoding S100A8 and S100A9 human, designed in the pQE32 plasmid, was performed by the thermal shock method into E. coli M15 bacteria. After bacterial growth in LB medium, the expression of two S100A8 and S100A9 subunits, the solubility of the protein by SDS-PAGE method was determined. Finally, the S100A8 / A9 complex was equally placed in the microtube. In the next step, the cytotoxic effects of calprotectin produced on the Nalm6 cell line were evaluated using the wst1 test. Then, the apoptosis in these cells was measured using flow cytometry methods with Annexin-V coloration. Results: In the current study, the results showed that the cytotoxic effects of Calprotectin are time and concentration- dependent. Therefore, it can reduce the tumor expression and had a beneficial effect by induced apoptosis in Nalm6 cell line. Conclusion: Calprotectin has an anti-tumor effect on the Nalm6 cell line by increasing apoptosis.

Background: Nowadays the use of plant-derived products has been extensively examined in the treatment of many types of gastrointestinal cancers such as hepatocarcinoma and colon cancer. Urtica dioica is a traditional herb that has many pharmacological effects and wildly used as a therapeutic agent in cancer. Herein, we have evaluated the effects of the different concentrations of Methanolic Extract of Urtica dioica (MEUD) on viability, death pattern, and expression of the apoptosis-related gene in normal Human Dermal Fibroblast (HDF), hepatocarcinoma cell lines (HepG2) and colon-cancer cell line (HCT116). Methods: A high-performance liquid chromatography method was developed to simultaneously separate 3 phenolic acids in MEUD. HepG2 and HCT116 cell lines as well as HDF normal cell line were cultured in suitable media. After 24 and 48h, in the cultured cell with different concentrations of MEUD, cells viability was assessed by MTT assay, and apoptosis was also evaluated at the cellular level by Annexin V/PI flow cytometry analyzing and AO/EB staining. BCL2 and BAX gene expressions were assessed by TaqMan real-time PCR assay. Results: MEUD showed antiproliferative effects on HepG2 and HTC116 cells after 48h with an IC50 value of about 410 and 420μg/ml, respectively (P < 0.001). Apoptotic cells were observed in HepG2 and HTC116 cells but not in HDF. Furthermore, the increased level of BAX/BCL-2 ratio was observed in HepG2 and HTC116 cells under the treatment of different concentrations of MEUD. Conclusion: The MEUD may influence hepatocarcinoma and colon-cancer cell lines at specific doses and change their proliferation rate by changing the expression of BAX and BCL2.

Background: Juniperus procera and Majra honey are well-known as a folk medicine in many countries. Objectives: This work aimed to study the immunomodulatory effects after mixing Majra honey, J. procera water leaves extract and silver Nanoparticles (AgNPs) on immune or cancer cells. Methods: Juniperus procera water leaves extract and 20% Majra honey were prepared. Both the extract and honey were used separately to synthesize AgNPs. AgNPs were characterized using UV/Vis spectrophotometry and electron microscopy. Bioactive molecules in honey and the extract were explored using Fourier Transform Infrared (FT-IR) spectroscopy. Protein profile of honey was explored using Sodium Dodecyl Sulfate- Polyacrylamide Gel Electrophoresis (SDS-PAGE) and honey sugar content was determined using High- Performance Liquid Chromatography (HPLC). Biological activities of honey and the extract were tested. Results: The results demonstrated the ability of the extract/honey to produce AgNPs in a spherical shape. The extract/honey contained many functional groups. SDS-PAGE of Majra honey showed many protein bands. HPLC revealed honey is of good quality and no external additives are added to it. The extract and extract+ AgNPs inhibited the growth of normal rat splenic cells while honey stimulated it. The extract+honey turned stimulatory to the splenic cells’ growth and significantly diminished the inhibitory potential of the extract containing AgNPs. Both the extract and honey have antimicrobial activities, this potential increased in the presence of AgNPs. Honey and Honey+AgNPs inhibited HepG2 cancer cell proliferation while Hela cell growth inhibited only with honey+AgNPs. Conclusion: Both honey and the extract have antibacterial and immunomodulatory potentials as well as the power to produce AgNPs. Majra honey alone showed anticancer activity against HepGe2 cells, but not against Hela cells, and when contained AgNPs had anticancer activity on both cell lines. Mixing of Majra honey with J. procera extract showed characterized immunomodulatory potentials that can be described as immunostimulant.

Background: Cassane-type diterpenoids are widely distributed in the medical plants of genus Caesalpinia. To date, plenty of cassane diterpenoids have been isolated from the genus Caesalpinia, and some of them were documented to exhibit multiple biological activities. However, the effects of these compounds on autophagy have never been reported. Objective: To investigate the effects and mechanisms of the cassane diterpenoids including Phanginin R (PR) on autophagy in Non-Small Cell Lung Cancer (NSCLC) A549 cells. Methods: Western blot analysis and immunofluorescence assay were performed to investigate the effects of the compounds on autophagic flux in A549 cells. The pathway inhibitor and siRNA interference were used to investigate the mechanism of PR. MTT assay was performed to detect cell viability. Results: PR treatment upregulated the expression of phosphatidylethanolamine-modified microtubule-associated protein Light-Chain 3 (LC3-II) in A549 cells. Immunofluorescence assay showed that PR treatment increased the production of red-fluorescent puncta in mRFP-GFP-LC3 plasmid-transfected cells, indicating PR promoted autophagic flux in A549 cells. PR treatment activated the c-Jun N-terminal Kinase (JNK) signaling pathway while it did not affect the classical Akt/mammalian Target of Rapamycin (mTOR) pathway. Pretreatment with the JNK inhibitor SP600125 or siRNA targeting JNK or c-Jun suppressed PR-induced autophagy. In addition, cotreatment with the autophagy inhibitor Chloroquine (CQ) or inhibition of the JNK/c-Jun signaling pathway increased PR-induced cytotoxicity. Conclusion: PR induced cytoprotective autophagy in NSCLC A549 cells via the JNK/c-Jun signaling pathway, and autophagy inhibition could further improve the anti-cancer potential of PR.

Background: Numerous studies suggest that non-steroidal anti-inflammatory drugs reduce cancer cell proliferation, progression, angiogenesis, apoptosis, and invasiveness. Objective: The current study focuses on the evaluation of novel mefenamic acid derivatives for the treatment of hepatocellular carcinoma. Methods: Derivatives were subjected to molecular modeling for prediction of pharmacological activity using software, followed by synthesis and in vitro assay. In in vivo study, disease was induced with N-Nitrosodiethylamine followed by 2-acetylaminofluorene orally for 2 weeks. After 12 weeks of induction, treatment was given for a period of one week. At the end of the treatment, determination of liver weight, a number of nodules, biochemical parameters, immunohistochemistry, histopathology, and gene expression studies, were carried out. Results: Based on molecular docking score for PDGF-α (Platelet-Derived Growth Factor) and IC50 values in HepG2 cell line study, JS-PFA was selected for the in vivo study where JS-PFA showed a statistically significant reduction in a number of nodules and liver weight. Protective role of JS-PFA has been observed in tumorspecific markers like α-fetoprotein, carcinoembryonic antigen, and lactate dehydrogenase levels. The JS-PFA has shown a significant reduction in PDGF-α levels as well as liver markers and total bilirubin levels. Histopathological analysis also showed a protective effect. The results of immunohistochemical analysis of P53 and down-regulation of vascular endothelial growth factor and matrix metalloproteinases-9 genes suggest that derivative inhibits PDGF mediated tumor growth and leads to apoptosis, inhibition of angiogenesis, and metastasis. Conclusion: The effectiveness of JS-PFA in our studies suggests targeting PDGF by COX 2 inhibitor can serve as a novel treatment strategy for the treatment of HCC.

Background: In cancer cells, re-activation of Epithelial-Mesenchymal Transition (EMT) program through Discoidin Domain Receptor1 (DDR1) leads to metastasis. DDR1-targeted therapy with siRNA might be a promising strategy for EMT inhibition. Therefore, the aim of this study was to investigate the effect of DDR1 knockdown in the EMT, migration, and apoptosis of prostate cancer cells. For this purpose, the expression of DDR1 was down regulated by the siRNA approach in LNcap-FGC and DU-145 prostate cancer cells. Methods: Immunocytochemistry was carried out for the assessment of EMT. E-cadherin, N-cadherin, Bax, Bcl2, and the phosphorylation level of Proline-rich tyrosine kinase 2 (Pyk2) and Map Kinase Kinase 7 (MKK7) was determined using the western blot. Wound healing assay was used to evaluate cell migration. Flow cytometry was employed to determine the apoptosis rate in siRNA-transfected cancer cells. Results: Our findings showed that the stimulation of DDR1 with collagen-I caused increased phosphorylation of Pyk2 and MKK7 signaling molecules that led to the induction of EMT and migration in DU-145 and LNcap- FGC cells. In contrast, DDR1 knockdown led to significant attenuation of EMT, migration, and phosphorylation levels of Pyk2 and MKK7. Moreover, DDR1 knockdown via induction of Bax expression and suppression of Bcl-2 expression induces apoptosis. Conclusion: Collectively, our results indicate that the DDR1 targeting with siRNA may be beneficial for the inhibition of EMT and the induction of apoptosis in prostate cancer.

Background: Targeting evolutionarily conserved proteins in malignant cells and the adapter proteins involved in signalling that generates from such proteins may play a cardinal role in the selection of anti-cancer drugs. Drugs targeting these proteins could be of importance in developing anti-cancer drugs. Objectives: We inferred that drugs like loperamide and promethazine that act as antagonists of proteins conserved in cancer cells like voltage-gated Calcium channels (Cav), Calmodulin (CaM) and drug efflux (ABCB1) pump may have the potential to be re-purposed as an anti-cancer agent in Prostate Cancer (PCa). Methods: Growth and cytotoxic assays were performed by selecting loperamide and promethazine to target Cav, CaM and drug efflux (ABCB1) pumps to elucidate their effects on androgen-independent PC3 and DU145 PCa cell lines. Result: We show that loperamide and promethazine in doses of 80-100μg/ml exert oncocidal effects when tested in DU145 and PC3 cell lines. Diphenhydramine, which shares its targets with promethazine, except the CaM, failed to exhibit oncocidal effects. Conclusion: Anti-cancer effects can be of significance if structural analogues of loperamide and promethazine that specifically target Cav, CaM and ABCB1 drug efflux pumps can be synthesized, or these two drugs could be re-purposed after human trials in PCa.

Background: Rosin (Colophony) is a natural resin derived from species of the pine family Pinaceae. It has wide industrial applications including printing inks, photocopying paper, adhesives and varnishes, soap and soda. Rosin and its derivatives are employed as ingredients in various pharmaceutical products such as ointments and plasters. Rosin-based products contain allergens that may exert some occupational health problems such as asthma and contact dermatitis. Objective: Our knowledge of the pharmaceutical and medicinal properties of rosin is limited. The current study aims at investigating the cytotoxic potential of Rosin-Derived Crude Methanolic Extract (RD-CME) and elucidation of its mode-of-action against breast cancer cells (MCF-7 and MDA-MB231). Methods: Crude methanol extract was prepared from rosin. Its phenolic contents were analyzed by Reversed- Phase High-Performance Liquid Chromatography (RP-HPLC). Antioxidant activity was evaluated by DPPH radical-scavenging assay. Antiproliferation activity against MCF-7 and MDA-MB231 cancerous cells was investigated by MTT assay; its potency compared with doxorubicin as positive control and specificity were assessed compared to two non-cancerous cell lines (BJ-1 and MCF-12F). Selected apoptosis protein markers were assayed by western blotting. Cell cycle analysis was performed by Annexin V-FITC/PI FACS assay. Results: RD-CME exhibited significant and selective cytotoxicity against the two tested breast cancer cells (MCF-7 and MDA-MB231) compared to normal cells as revealed by MTT assay. ELISA and western blotting indicated that the observed antiproliferative activity of RD-CME is mediated via the engagement of an intrinsic apoptosis signaling pathway, as judged by enhanced expression of key pro-apoptotic protein markers (p53, Bax and Casp 3) relative to vehicle solvent-treated MCF-7 control cells. Conclusion: To our knowledge, this is the first report to investigate the medicinal anticancer and antioxidant potential of crude methanolic extract derived from colophony rosin. We provided evidence that RD-CME exhibits strong antioxidant and anticancer effects. The observed cytotoxic activity against MCF-7 is proposed to take place via G2/M cell cycle arrest and apoptosis. Colophony resin has a great potential to join the arsenal of plantderived natural anticancer drugs. Further thorough investigation of the potential cytotoxicity of RD-CME against various cancerous cell lines is required to assess the spectrum and potency of its novel activity.