Phthalimide Analogs Enhance Genotoxicity of Cyclophosphamide and Inhibit Its Associated Hypoxia.

Cyclophosphamide (CP) is a mutagen that is used in cancer chemotherapy, due to its genotoxicity and as an immunosuppressive agent. Thalidomide (TH) is another cancer chemotherapeutic drug. In this study, the cytogenotoxicity and hypoxia modulatory activities of two phthalimide analogs of TH have been evaluated with/without CP. Both analogs have increased CP-stimulated chromosomal aberrations than those induced by TH, including gaps, breaks/fragments, deletions, multiple aberrations, and tetraploidy. The analogs have elevated the cytotoxic effect of CP by inhibiting the mitotic activity, in which analog 2 showed higher mitosis inhibition. CP has induced binucleated and polynucleated bone marrow cells (BMCs), while micronuclei (MN) are absent. TH and analogs have elevated the CP-stimulated binucleated BMCs, while only analogs have increased the CP-induced polynucleated BMCs and inhibited the mononucleated BMCs. MN-BMCs were shown together with mononucleated, binucleated, and polynucleated cells in the CP group. Both analogs have elevated mononucleated and polynucleated MN-BMCs, whereas in presence of CP, TH and analogs have enhanced mononucleated and binucleated MN-BMCs. The analogs significantly induce DNA fragmentation in a comet assay, where analog 1 is the strongest inducer. The treatment of mice with CP has resulted in a high hypoxia status as indicated by high pimonidazole adducts and high HIF-1α and HIF-2α concentrations in lymphocytes. Analogs/CP-treated mice showed low pimonidazole adducts. Both analogs have inhibited HIF-1α concentration but not HIF-2α. Taken together, the study findings suggest that both analogs have a higher potential to induce CP-genotoxicity than TH and that both analogs inhibit CP-hypoxia via the HIF-1α-dependent mechanism, in which analog 1 is a more potent anti-hypoxic agent than analog 2. Analog 1 is suggested as an adjacent CP-complementary agent to induce CP-genotoxicity and to inhibit CP-associated hypoxia.

Matrix Metalloproteinase-11 Gene Polymorphisms as a Risk for Hepatocellular Carcinoma Development in Egyptian Patients.

BACKGROUND: Chronic hepatitis C (CHC) virus infection is one of major risk factors of hepatocellular carcinoma (HCC) in Egypt, which is a major cause of cancer mortalityin the world. Matrix metalloproteinase-11 (MMP-11) has an important role in tumor migration and metastasis. Therefore, this study aimed to determine relation between MMP-11 gene polymorphisms and risk of HCC development among Egyptian cirrhotic patients. SUBJECTS AND METHODS: Two hundred and sixty patients were included, 140 of them with HCC on top of CHC and 120 patients with post CHC liver cirrhosis (LC) as well as 140 subjects were enrolled in the study as healthy controls. Two single nucleotide polymorphisms (SNPs) rs738791 and rs738792 for MMP-11 gene were done using real-time PCR. RESULTS: Combination of CT and TT allele of rs738791 genotypes was more significantly frequent in HCC compared to LC patients and controls, however, a higher frequency of T allele was found in HCC patients compared to LC and controls. In spite of lake of significant difference between patient groups regarding the rs738792 genotypes, the CC genotype was considered a risk of developing portal vein thrombosis, and was associated with advanced tumor stage, increased tumor size, higher Cancer of the Liver Italian Program [CLIP] score, more advanced Barcelona stage [D] and with child Pugh class [C]. CONCLUSION: Genetic variations in MMP-11 may be implicated in post HCV-HCC development and might be dependable biomarkers for HCC progression.

Design, synthesis, biological evaluations, molecular docking, and in vivo studies of novel phthalimide analogs.

A series of novel phthalimide analogs containing an indole or brominated indole moiety were synthesized and their antimicrobial activity was evaluated. Compound 8 showed a broad spectrum activity, revealing 53-67% of erythromycin activity on the tested bacteria and 60-70% of miconazole activity on the tested fungi. Anticancer activity was evaluated on the cell lines HepG2, MCF-7, A549, H1299, and Caco2. The results revealed that the new phthalimide analog 8 has broad-spectrum anticancer activity toward all the tested cancer cell lines, followed by compound 11, which showed good activity toward all the tested cell lines except for MCF-7. The ability of the promising analogs 5, 8, and 11 to bind to topoisomerase II DNA gyrase was investigated. Caspase-3 activation and Bcl-2 assay of the best active derivatives 8, 11 in addition to compound 5 were evaluated. The antifibrotic activity was studied in an in vivo model and the histopathological studies revealed that treatment with the new compound 8 improved the fibrotic liver tissues to normality.

Anti-inflammatory effect of thalidomide dithiocarbamate and dithioate analogs.

Thalidomide has anti-inflammatory, immunomodulatory, and anti-angiogenic properties. It has been used to treat a variety of cancers and autoimmune diseases. This study aimed to characterize anti-inflammatory activities of novel thalidomide analogs by exploring their effects on splenocytes proliferation and macrophage functions and their antioxidant activity. MTT assay was used to assess the cytotoxic effect of thalidomide analogs against splenocytes. Tumor necrosis factor (TNF-α) and nuclear factor kappa B (NF-κB-P65) were determined by enzyme-linked immunosorbent assay (ELISA). Nitric oxide (NO) was estimated by colorimetric assay. Antioxidant activity was examined by ORAC assay. Our results demonstrated that thalidomide dithioate analog 2 and thalidomide dithiocarbamate analog 4 produced a slight increase in splenocyte proliferation compared with thalidomide. Thalidomide dithiocarbamate analog 1 is a potent inhibitor of TNF-α production, whereas thalidomide dithiocarbamate analog 5 is a potent inhibitor of both TNF-α and NO. Analog 2 has a pronounced inhibitory effect on NF-κB-P65 production level. All thalidomide analogs showed prooxidant activity against hydroxyl (OH) radical. Analog 1 and thalidomide dithioate analog 3 have prooxidant activity against peroxyl (ROO) radical in relation to thalidomide. On the other hand, analog 4 has a potent scavenging capacity against peroxyl (ROO) radical compared with thalidomide. Taken together, the results of this study suggest that thalidomide analogs might have valuable anti-inflammatory activities with more pronounced effect than thalidomide itself.

Synthesis and evaluation of thalidomide and phthalimide esters as antitumor agents.

A series of thalidomide and phthalimide ester analogs were efficiently synthesized from N-chloromethylthalidomide, N-chloromethylphthalimide, and N-(2-bromoethyl)phthalimide derivatives with various biologically important carboxylic acids. The synthesized compounds were purified and characterized by various chromatographic and spectroscopic techniques. The antitumor activity of all the synthesized compounds was screened against human liver and breast cancer cells, which showed that phthalimide ester 6a was the best cytotoxic compound against MCF7 cells, while all of the tested compounds showed a non-cytotoxic effect against HepG2 cells. Compounds 5a, 6a, and 7a possess immunosuppressant effect, while compounds 5c, 5d, 6c, 6d, 7c, and 7d showed an immunostimmulatory effect. Meanwhile, estimation of the binding affinity for all the synthesized compounds toward the vascular endothelial growth factor receptor (VEGFR) showed that compounds 5a, 5b, and 7d were the most potent inhibitors.

In vitro anti-proliferative and anti-angiogenic activities of thalidomide dithiocarbamate analogs.

Inhibition of angiogenesis is currently perceived as a promising strategy in the treatment of cancer. The anti-angiogenicity of thalidomide has inspired a second wave of research on this teratogenic drug. The present study aimed to investigate the anti-proliferative and anti-angiogenic activities of two thalidomide dithiocarbamate analogs by studying their anti-proliferative effects on human umbilical vein endothelial cells (HUVECs) and MDA-MB-231 human breast cancer cell lines. Their action on the expression levels of IL-6, IL-8, TNF-α, VEGF165, and MMP-2 was also assessed. Furthermore, their effect on angiogenesis was evaluated through wound healing, migration, tube formation, and nitric oxide (NO) assays. Results illustrated that the proliferation of HUVECs and MDA-MB-231 cells was not significantly affected by thalidomide at 6.25-100µM. Thalidomide failed to block angiogenesis at similar concentrations. By contrast, thalidomide dithiocarbamate analogs exhibited significant anti-proliferative action on HUVECs and MDA-MB-231 cells without causing cytotoxicity and also showed powerful anti-angiogenicity in wound healing, migration, tube formation, and NO assays. Thalidomide analogs 1 and 2 demonstrated more potent activity to suppress expression levels of IL-6, IL-8, TNF-α, VEGF165, and MMP-2 than thalidomide. Analog 1 consistently, showed the highest potency and efficacy in all the assays. Taken together, our results support further development and evaluation of novel thalidomide analogs as anti-tumor and anti-angiogenic agents.

Effect of thalidomide dithiocarbamate analogs on the intercellular adhesion molecule-1 expression.

Thalidomide has been reported to have anti-angiogenic and antimetastatic effects. Intercellular adhesion molecule-1 (ICAM-1) was shown to be involved in monocyte adherence to epithelial cells and cancer cell invasion. Novel thalidomide dithiocarbamate analogs (containing 2 sulfur atoms) were designed and synthesized as potential anti-tumor agents. The aim of this work is to investigate their anti-tumor effect against transplantable experimental tumor, Ehrlich ascites carcinoma (EAC), in mice by studying the changes in cell's biochemical profile, the expression of ICAM-1 and nitric oxide (NO) and their association with tumor burden. As shown in our results, treatment of solid tumor-bearing mice with thalidomide 1 resulted in a significant reduction in tumor volume with 75.4% inhibition, a significant decrease in lactate dehydrogenase (LDH), ICAM-1 expression and NO. Thalidomide dithiocarbamate analogs 2 and 3 exhibited a potent effect to reduce the volume of solid tumor with 96.7% and 96.5% inhibition, respectively, a significant ability to increase the albumin, alanine aminotransferase (ALT) and glucose levels and to diminish LDH, ICAM-1 expression and NO. Thalidomide dithiocarbamate analog 3 has more potent anti-tumor activity as compared with thalidomide 1 or its dithiocarbamate analog 2. Taken together, our study improved that the dithiocarbamate analogs 2 and 3 are more potent anti-tumor agents with more pronounced effect than thalidomide 1 itself.

Design, synthesis and antitumor evaluation of novel thalidomide dithiocarbamate and dithioate analogs against Ehrlich ascites carcinoma-induced solid tumor in Swiss albino mice.

A series of 16 novel thalidomide sulfur analogs containing one and two sulfur atoms 2 and 4-18, respectively, were designed and synthesized. These compounds were screened for in vitro antitumor activity against Ehrlich ascites carcinoma (EAC) cell line and exhibited potent cytotoxic activity. On the bases of the obtained results for in vitro cytotoxic activity, thalidomide sulfur analogs containing two sulfur atoms 8, 9, 13 and 14 were selected and tested in vivo against EAC-induced solid tumor in female mice compared to thalidomide 1 as well as its analog 2 and exhibited a highly significant reduction in tumor volume (TV). Results illustrated the antioxidative activity of these compounds as the level of hepatic lipid peroxidation decreased and levels of antioxidant enzymes like superoxide dismutase (SOD) and catalase were elevated. The histopathological investigations revealed that thalidomide sulfur analogs 2, 8, 9, 13 and 14 have antimitotic, apoptotic and necrotic activities against solid tumor. These compounds lead to increase of Fas-L expression. The immunohistochemical studies showed a decrease in Ki67 and vascular endothelial growth factor (VEGF) staining in tumor cells from treated-animals when compared with non-treated groups, which suggests an inhibition of tumor proliferation rate and angiogenic process associated with tumor growth. Compounds 9 and 13 were the most potent compounds in tumor necrosis without liver necrosis. At the same time, treatment with compound 9 resulted in liver degeneration.

Rapid and efficient synthesis of 4-substituted pyrazol-5-one under microwave irradiation in solvent-free conditions.

New heterocyclic compounds containing pyrazol-5-one coupled with benzimidazole, benzothiazole, benzoxazole, quinoline, naphthyridin, and pyrazole were synthesized. Comparative investigations to synthesize these interesting classes of heterocyclic compounds through conventional heating or under microwave-irradiation conditions were presented. Synthesized compounds 1a, 2a, 4k, 3a, c, 5a, b, 6b, 7a, b, d, 8a, and 9a were evaluated for their antitumor activity. Some of these compounds exhibited promising antitumor activity.