Anti-Cancer Agents in Medicinal Chemistry (Formerly Current Medicinal Chemistry - Anti-Cancer Agents) - Volume 18, Issue 8, 2018

Background: Human cancer cell lines are valuable models for anti-cancer drug development. Although all cancer cells share common biological features, each cancer cell line has unique genotypic/ phenotypic characteristics that affect drug response. Thus, the information obtained with a specific cancer cell line cannot be easily extrapolated to other cancer cells. Consequently, cell line selection during experimental design is critical for providing proper and clinically relevant structure-activity analysis. Methods: Herein, we critically review the use of cancer cell lines as tools for activity analysis by comparing two different scenarios: i) the use of multiple cancer cell lines, with the NCI-60 Program as the most representative example; and, ii) the selection of a single cell line with specific biological characteristics that match the rationale of compound design. Results: Considering that most laboratories evaluate the activity of new compounds using few cell lines, we provide a systematic strategy for selection based on the expression levels and genetic status of the target and the effectiveness of target inhibition or silencing. We exemplify the use of public databases for data retrieval and analysis as well as the critical comparison of such information with published results. Conclusion: This approach refines cell line selection, avoiding the perpetuation of published poor selection and enhancing the relevance of the results.

Background: Tartrate-resistant acid phosphatase 5 (ACP5) is an evolutionarily conserved and multifunctional protein that is involved in generations of reactive oxygen species, normal bone development, osteoblast regulation and macrophage function, affecting a series of pathways, as well as reflecting bone resorption and osteoclast activity. Methods: Literature searches, systematic reviews and assessments about the structure, distribution, regulation and novel functions of ACP5 were performed in this review from PubMed and Medline databases. Results: Studies demonstrate that RANKL can increase the expression of ACP5 through NFATc1 and c-Fos to accelerate osteoclastogenesis, which also can be regulated by many regulators. Based on the aforementioned information, it is shown that ACP5, together with the phosphatase activity, can medicate the progression and development of human genetic diseases and cancer. Conclusion: As a novel target, ACP5 plays a critical role in preventing, monitoring and treating various kinds of tumors, as well as accelerating the development of a promising therapeutic strategy for human genetic diseases. However, the explicit mechanism between ACP5 and cancer is not so clear. It is necessary and significant for us to pay more in-depth attention.

Background: Conventional therapeutic strategies for tumors have had limited success, and innovative and more effective approaches to treatment are urgently required. The ancient idea that various biological, bacterial, yeast, viral, and parasitic agents can be used as cancer therapeutics has gradually attracted considerable interest. Certain parasites have been widely discussed in association with human and animal tumors. The purpose of this review was to examine previous literatures which investigates the relations between Trichinella spiralis (T. spiralis) and tumors. Methods: Using PubMed, articles published before 2018 in the whole world have been searched and comprehensively reviewed. Results: Many researches have provided proofs that T. spiralis possesses antitumor activities. The antitumor effect of T. spiralis was first described in the 1970s. However, its research has been inconsistent, and little progress has been made in this field. Therefore, the mechanisms underlying these inhibitory effects are still unclear, and convincing evidence of the links between T. spiralis and the prevention or treatment of tumors from clinical trials is absent. Meanwhile, some other researches also suggested that T. spiralis may cause or contribute to coinfection with a tumors. Conclusion: The review has highlighted the scientific literature focussing on evidence for T. spiralis to act as a pro- or antitumorigenic agent is summarized and discussed, in hope of contributing to a better understanding of the relations between T. spiralis and tumors.

Pim kinases, also known as Serine/Threonine kinases, are intensively studied protein drug targets in cancer research. They play crucial role in the regulation of signal transduction cascades that promote cell survival, proliferation and drug resistance. Pim kinases are overexpressed in several hematopoietic and solid tumors and support in vitro/in vivo malignant cell growth and survival, through cell cycle regulation and inhibition of apoptosis. Pim kinases do not have an identified regulatory domain, as they are constitutively active. They appear to be critical downstream effectors of a number of oncoproteins. When overexpressed, they mediate drug resistance to agents such as Rapamycin. X-ray crystallographic studies reveal that unlike other kinases, Pim kinases have a hinge region, which forms a unique binding pocket for ATP, offering a target for a large number of potent small-molecule Pim kinase inhibitors. Combination therapy of Pim kinase inhibitors with chemotherapeutic and other kinase modulators seems to produce an additive cytotoxic effect in cancer cells. Though clinical trials have been carried out on the first Pim inhibitory agent, SGI-1776, no concept data could be generated due to its early withdrawal. However, it has helped in accelerating the discovery of several novel Pim inhibitors in recent years. Current research on Pim kinase is expected to lead to a new generation of potent Pim kinase inhibitors with appropriate pharmacological profiles suitable for human cancer therapy in the near future. Herein, we review the synthetic route and mechanistical studies of Pim kinase inhibitors which are currently in human trials.

Background: Thiazole ring is an outstanding structure found in many biologically active compounds and clinically available drugs. Because of synthesis simplicity of its derivatives and having a wide range of biological aspects along with high effectiveness, new thiazole derivatives have been studied by medicinal chemists since many years. Objective: Some thiazole compounds combined with different heterocyclic rings were acquired in this study. Novel 5-(4-substituted benzylidene)-2-[(4,5-dimethylthiazol-2-yl)amino]thiazol-4(5H)-one derivatives (4a-g) and 2-(heteroaryl-2/3/5-yl)thio-N-(4,5-dimethylthiazol-2-yl)acetamide (4h-p) derivatives were synthesized starting from 2-amino-4,5-dimethylthiazole. The obtained compounds were evaluated to determine their antiproliferative activity. Method: Final compounds (4a-g) were obtained with a ring closure reaction; other final compounds (4h-p) were acquired via the reaction of mercapto heterocycles with Hantzsch thiazole synthesis intermediate. To evaluate antiproliferative activity of them, the compounds were tested on A549 adenocarcinomic human alveolar basal epithelial cells line, C6 rat glioma cell line and NIH/3T3 mouse embryo fibroblast cell line according to the conventional MTT method. Besides, the selected compounds were studied to find out which pathway cell deaths caused via Annexin V/PI staining. Results: Compounds 4f, 4j and 4p exhibited the highest cytotoxicity on A549 with a non-toxic profile. Also, 4f, 4h, 4j and 4p were determined as the most antiproliferative compounds on C6 cell line. Furthermore, compound 4p induced apoptosis of A549 cell with a level of 23.5% and compound 4h induced C6 cell with a level of 37.5%. Conclusion: Considering the structure of the compounds, although thiazolidine containing compounds 4a-g exhibited higher activity in general, compounds 4p containing 5-chlorobenzothiazole moiety showed the highest cytotoxicity. It could be expressed with the conspicuous antitumor efficiency of benzothiazole ring.

Background: Quinoline is a privileged scaffold especially known with antimalarial and antibacterial drugs before, presently followed anticancer efficiency with a new group of protein kinase inhibitors. Objective: In this work, combining quinoline ring, hydrazone and sulphonamide groups, we have synthesized N'-arylidene-2-[4-(quinolin-8-ylsulfonyl)piperazin-1-yl]acetohydrazide derivatives (3a-o) and evaluated their in vitro anticancer activity against cancerous cell lines PANC-1, CAPAN-1, and healthy cell line hTERT-HPNE. Method: Fifteen compounds were synthesized a simple, well-known three-step synthetic procedure starting from 8-quinolinesulfonylchloride. Cytotoxicity studies were performed according to the conventional MTT method. As a second stage, flow cytometric analysis was done to the nine most cytotoxic compounds for determining the mechanism of action which could be apoptosis and/or necrosis. Results/Conclusion: According to anticancer activity evaluation, compound 3b bearing 4-methyl phenyl moiety exhibited significant cytotoxicity which has an IC50 value nearly four-fold lower than cisplatin displayed, whereas compound 3f bearing 4-trifluoromethyl phenyl moiety showed two-fold potency of the standard drug against PANC-1 cell line. Compounds 3h, 3k and 3n against CAPAN-1 also showed significant cytotoxicity, selectively. The most active compounds 3b, 3c, 3d, 3f, 3g, 3h, 3k and 3n against PANC-1 and compounds 3f, 3g, 3h, 3k and 3n against CAPAN-1 were selected to be studied in flow cytometry. Compound 3b induced apoptosis of PANC-1 cells with a percentage of 16.0%, whereas compound 3h induced apoptosis of CAPAN-1 cells with a value of 20.6%.

Background: Curcumin is a potent anticancer agent and has great potential efficacy against different types of cancers. A major disadvantage of curcumin, however, is its poor solubility and bioavailability. Objective: The aim of the present work is to synthesize chitosan and curcumin-loaded chitosan nanoparticles and their characterization through various physicochemical methods and cellular uptake in cervical cancer cell line SiHa. Method: Chitosan nanoparticles were synthesized through the method of ionic gelation of chitosan with sodium Tripolyphosphate (TPP). In addition, the internal structure of chitosan nanoparticles and curcumin loaded chitosan nanoparticles were characterized by DLS, UV-Visible spectrophotometer, DSC, LCMS and LDH assay. Results: The studies presented demonstrate that curcumin-loaded chitosan nanoparticles showed increased uptake in the SiHa cells as compared to free curcumin and chitosan nanoparticles did not show any significant uptake in SiHa cell line. The curcumin-loaded chitosan nanoparticles released more lactate and lower ATP as compared to native curcumin in cervical cancer lines such as SiHa, CaSki and HeLa. Conclusion: Thus, chitosan based curcumin nanoparticles could be used as a potent vector / delivery agent for drug targeting in the treatment of cervical cancer.

Background: Although conventional chemotherapy is the most common method for cancer treatment, it has several side effects such as neuropathy, alopecia and cardiotoxicity. Since the drugs are given to body systemically, normal cells are also affected, just like cancer cells. However, in recent years, targeted drug delivery has been developed to overcome these drawbacks. Objective: The aim of this study was targeted co-delivery of doxorubicin (Dox) which is an anticancer agent and D-α-Tocopherol polyethylene glycol 1000 succinate (vitamin E TPGS or simply TPGS) to breast cancer cells. For this purpose, Magnetic Nanoparticles (MNPs) were synthesized and coated with Oleic Acid (OA). Coated nanoparticles were encapsulated in Poly Lactic-co-Glycolic Acid (PLGA) and TPGS polymers and loaded with Dox. The Nanoparticles (NPs) were characterized by Fourier Transform Infrared (FTIR) spectroscopy, zetapotential analysis, Dynamic Light Scattering (DLS) analysis, Thermal Gravimetric Analysis (TGA) and Scanning Electron Microscope (SEM) analysis. Results: The results showed that NPs were spherical, superparamagnetic and in the desired range for use in drug targeting. The targetability of NPs was confirmed. Moreover, TPGS and Dox loading was shown by TGA and FTIR analyses. NPs were internalized by cells and the cytotoxic effect of drug loaded NPs on sensitive (MCF-7) and drug-resistant (MCF-7/Dox) cells were examined. It was seen that the presence of TPGS increased cytotoxicity significantly. TPGS also enhanced drug loading efficiency, release rate, cellular internalization. In MCF- 7/Dox cells, the drug resistance seems to be decreased when Dox is loaded onto TPGS containing NPs. Conclusion: This magnetic PLGA nanoparticle system is important for new generation targeted chemotherapy and could be used for breast cancer treatment after in vivo tests.

Background: Despite the development of conventional therapies including surgery, radiotherapy, chemotherapy and hyperthermia, the prognosis remains very poor. Recently, integration of conventional therapy and multifunctional nanoparticles have attracted a lot of attention because it produces a synergistic effect and better diagnostic and therapeutic efficiency. Objective: This study aimed to investigate the uptake and cytotoxic effects of Polycaprolactone (PCL)/chitosan (CHI)-coated Superparamagnetic Iron Oxide Nano-Graphene Oxide (SPION-NGO) as a carrier of 5-fluorouracil (5-Fu) and Radiofrequency (RF) hyperthermia using an Alternate Magnetic Field (AMF) with 13.56 MHz frequency on the proliferation capacity level of CT26 colon cancer cell line in a monolayer culture. Method: The release of the newly synthesised 5-Fu-loaded PCL/CHI-SPION-NGO was measured in Phosphate Buffered Saline (PBS) using the dialysis bag method. The cellular uptake of 5-Fu-loaded PCL/CHI-SPIONNGO was measured using Atomic Absorption Spectroscopy (AAS). The cytotoxic effects of 5-Fu, 5-Fu- PCL/CHI-SPION-NGO and PCL/CHI-SPION-NGO with and without RF hyperthermia were determined using the colony formation assay. Results: Particle size and zeta potential of 5-Fu-PCL/CHI-SPION-NGO and PCL/CHI-SPION-NGO were 61.2 nm and -1.87 mV and 43.4 nm and -10.19 mV, respectively. Spectroscopy results demonstrated that the cellular uptake of 5-Fu-PCL/CHI-SPION-NGO increased with elevated nanostructure concentrations. The results revealed that the proliferation capacity of the cells decreased with 5-Fu or 5-Fu-PCL/CHI-SPION-NGO in combination with RF hyperthermia. Furthermore, extent of reduction in colony number following treatment with 5-Fu-PCL/CHI-SPION-NGO in combination with AMF was significantly more than 5-Fu + hyperthermia. Conclusion: Therefore, PCL/CHI-SPION-NGO can deliver 5-Fu more efficiently into the CT26 cells.

Background: The heptaprotective flavonolignan silibinin and dehydrosilibinin have exhibited moderate antiproliferative activities toward many cancer cell lines. Considering of the nontoxic profile of these natural products, chemical modification to enhance the anticancer potentials is promising. Method: A series of 7-O-aminoalkyl-2,3-dehydrosilibinin derivatives were synthesized and evaluated for their antiproliferative activities against several cancer cell lines. Results: A number of the synthesized dehydrosilibinin derivatives exhibited greatly enhanced potency with 50% growth inhibition at low micromolar concentrations. Structure activity study indicated that the distance between N and 7-O on the side chain has a limited influence on the antiproliferative activity, while the presence of a morpholino group decreases the antiproliferative activities dramatically. Flow cytometry based assays on human colon cancer HCT116 cells revealed that 6a and 6c, two of the most potent derivatives, effectively arrested the cell cycle in the G2 phase and stimulated cell apoptosis. Conclusion: Our findings suggest that attaching an appropriate tertiary amino alkyl side chain through 7-Oalkylation on 2,3-dehydrosilibinin, would be a viable strategy for the development of silibinin derivatives as anticancer agents.

Background: The network interactions link human disease proteins to regulatory cellular pathways leading to better understanding of protein functions and cellular processes. Revealing the network of signaling pathways in cancer through protein-protein interactions at molecular level enhances our understanding of Hepatocellular Carcinoma (HCC). Objective: A rodent model for study of HCC was developed to identify differentially expressed proteins at very early stage of cancer initiation and throughout its progression. Methodology: HCC was induced by administrating N-Nitrosodiethylamine (DEN) and 2-aminoacetylfluorine (2-AAF) to male Wistar rats. Proteomic approaches such as 2D-Electrophoresis, PD-Quest, MALDI-TOF-MS and Western blot analyses have been used to identify, characterize and validate the differentially expressed proteins in HCC-bearing animals vis-a-vis controls. Results: The step-wise analysis of morphological and histological parameters revealed HCC induction and tumorigenesis at 1 and 4 months after carcinogen treatment, respectively. We report a novel protein network of 735 different proteins out of which eight proteins are characterized by MALDI-TOF-MS analysis soon after HCC was chemically induced in rats. We have analyzed four different novel routes representing the association of experimentally identified proteins with HCC progression. Conclusion: The study suggests that A-Raf, transthyretin and epidermal growth factor receptor play major role in HCC progression by regulating MAPK signaling pathway and lipid metabolism leading to continuous proliferation, neoplastic transformation and tumorigenesis.

Background: The meadowsweet (Filipendula ulmaria (L.) Maxim.) may have a cancer prophylactic activity, since its extracts exhibit antioxidant, anti-inflammatory and other effects. We investigated the ability of a meadowsweet decoction to inhibit mammary carcinogenesis induced by intramammary injections of Methylnitrosourea (MNU) to the target organ in rats. Materials and Methods: The chemical composition of meadowsweet extracts was studied by traditional methods. In animal experiments, adult outbred female rats received single injections of MNU at a dose 1mg directly into the tissue of each mammary gland. After carcinogenic exposure one group (MNU) of rats continued to receive standard feed and tap water throughout life. In another group (MNU+meadowsweet), rats were given daily a decoction of the meadowsweet instead of drinking water and standard feed. Results: Meadowsweet extracts showed a sufficiently high content of flavonoids and tannins and also some individual phenolic compounds. In rats after injections of MNU the overall incidence of tumors was 90% with tumor multiplicity of 3.1. The majority of rats (86%) developed multiple malignant tumors of the mammary gland (most often adenocarcinomas). In rats from the group MNU+meadowsweet, there was a statistically significant decrease of the overall tumor multiplicity-by 1.5 times, and the incidence and multiplicity of breast tumors-by 1.6 and 2.2 times, respectively. Conclusions: Meadowsweet extract can be considered an effective inhibitor of breast carcinogenesis.

Background: Extensive studies were reported in the synthesis of several phthalazine derivatives as promising anticancer agents as potent VEGFR-2 inhibitors. Vatalanib (PTK787) was the first anilinophthalazine published derivative as a potent inhibitor of VEGFR. The discovery of vatalanib as a clinical candidate led to the design and synthesis of different anilinophthalazine derivatives as potent inhibitors for VEGFR-2. The objective of present research work is the synthesis of new agents with the same essential pharmacophoric features of the reported and clinically used VEGFR-2 inhibitors (e.g vatalanib and sorafenib). The main core of our molecular design rationale comprised bioisosteric modification strategies of VEGFR-2 inhibitors at four different positions. Material and Methods: A correlation between structure and biological activity of our designed phthalazines was established using molecular docking and VEGFR-2 kinase assay. Results and Discussion: In view of their expected anticancer activity, novel triazolo[3,4-a]phthalazine derivatives 5-6a-o and 3-substituted-bis([1,2,4]triazolo)[3,4-a:4',3'-c]phthalazines 9a-b were designed, synthesized and evaluated for their anti-proliferative activity against two human tumor cell lines HCT-116 human colon adenocarcinoma and MCF-7 breast cancer. It was found that, compound 6o the most potent derivative against both HCT116 and MCF-7 cancer cell lines. Compounds 6o, 6m, 6d and 9b showed the highest anticancer activities against HCT116 human colon adenocarcinoma with IC50 of 7±0.06, 13±0.11, 15±0.14 and 23±0.22 μM respectively while compounds 6o, 6d, 6a and 6n showed the highest anticancer activities against MCF-7 breast cancer with IC50 of 16.98±0.15, 18.2±0.17, 57.54±0.53 and 66.45±0.67 μM respectively. Sorafenib as a highly potent VEGFR-2 inhibitor was used as a reference drug with IC50 of 5.47±0.3 and 7.26±0.3 μM respectively. Nine compounds were further evaluated for their VEGFR-2 inhibitory activity. Compounds 6o, 6m, 6d and 9b emerged as the most active counterparts against VEGFR-2 with IC50 values of 0.1±0.01, 0.15±0.02, 0.28±0.03 and 0.38±0.04 μM, respectively comparable to that of sorafenib (IC50 = 0.1±0.02) μM. Furthermore, molecular docking studies were carried out for all synthesized compounds to investigate their binding pattern and predict their binding affinities towards VEGFR-2 active site. In silico ADMET studies were calculated for the tested compounds. Most of our designed compounds exhibited good ADMET profile. Conclusion: The obtained results showed that, the most active compounds could be useful as a template for future design, optimization, adaptation and investigation to produce more potent and selective VEGFR-2 inhibitors with higher anticancer analogs.

Objective: The aim of this study was to investigate the mechanism of oxaliplatin in the induction of neuropathic pain as a symptom of Chemotherapy-Induced Peripheral Neuropathy (CIPN). Methods: The CIPN rat model was induced with a one-time injection of oxaliplatin, and the paw withdrawal response was determined using von Frey filaments. The Paw Withdrawal Threshold (PWT) value was recorded and the Dorsal Horn (DH) and Dorsal Root Ganglion (DRG) tissues were collected. The mRNA and protein levels of Calcineurin (CaN), Nuclear Factor of Activated T cells (NFAT), and other relevant cytokines were determined. CaN and NFAT inhibition reagents, FK506 and 11R-VIVIT, were applied in order to investigate the functions of the CaN/NFAT pathway in the neuropathic pain processes. The levels of the downstream inflammatory cytokines, TNF-α and IL-1β, were assessed by ELISA. Results: The application of oxaliplatin reduced the value of PWT by 4 times on days 7#136;4±1.33#137;and 14#136;5.13±3.07#137;compared with the control group(14±0.91; 13.67±0.76). After treatment, the CaN mRNA level decreased and that of NFAT increased in DH and DRG tissues (P<0.05). However, treatment with FK506 and 11R-VIVIT decreased the value of PWT that had increased after oxaliplatin treatment. The expression of downstream cytokines related to the CaN/NFAT pathway increased, including CCR2, COX2, p-ERK, and p-P38 (all p<0.05). In addition, when the CaN/NFAT pathway was activated, the concentration of TNFα increased to 40pg/mg in DH tissues and 60pg/mg in DRG tissues compared with the control group, while the concentration of IL-1β increased to over 60pg/mg in DH and DRG tissues. Conclusion: It was the first time to prove that oxaliplatin-induced neuropathic pain was correlated to the activation of the CaN/NFAT pathway in our rat model. This finding can provide a new direction to explore the mechanism of oxaliplatin-induced neuropathic pain.

Aims: Tyrosine kinases and topoisomerase I are common target enzymes for the majority of the anticancer agents. In contrast to quinazolines and quinolines, kinase inhibitors and topoisomerase inhibitors incorporating cinnoline scaffold are relatively infrequent. Thus the aim of this work was to replace the former scaffolds with the latter one. Eighteen novel cinnoline derivatives were designed, synthesized and characterized using both microanalytical and spectral data. Methods: The cytotoxic activity of the new compounds was screened in vitro against both human breast cancer cells and normal breast cells. Results: The enzymatic inhibition activity of promising candidates against both epidermal growth factor receptor tyrosine kinase and topoisomerase I was accomplished. Conclusions: Cell cycle profiles were observed at IC50 doses of representative biologically active compounds. Compound 7 represented a new scaffold incorporating triazepinocinnoline ring system and showed outstanding cytotoxic activity against MCF-7 (0.049 μM), tyrosine kinase inhibition (0.22 μM), apoptosis percentage and the highest selectivity index.

Due to an oversight one of the author’s name was published wrong in the article entitled “Design, Synthesis and Biological Evaluation of a Phenyl Butyric Acid Derivative, N-(4-chlorophenyl)-4- phenylbutanamide: A HDAC6 Inhibitor with Anti-proliferative Activity on Cervix Cancer and Leukemia Cells” in “Anti-Cancer Agents in Medicinal Chemistry, 2017, Vol. 17, No. 10. pp. 1441.” The correct names of all authors are given below: Rodríguez-Fonseca RA, Sixto-López Y, Fragoso-Vázquez MJ, Flores-Mejía R, Cabrera-Pérez LC, Vázquez-Moctezuma I, Rosales-Hernández MC, Bello M, Martínez-Archundia M, Trujillo-Ferrara JG, Becerra-Martínez E, Correa-Basurto J.