Samia Shouman

Melilotus indicus, is a traditional medicine used as analgesic and emollient. Although Melilotus indicus extract (MIE) has recently been shown to suppress growth of several tumor cell lines, information regarding its antitumor mechanism is completely unknown. Here, we report the mechanism underlying the effects of MIE on human hepatocellular carcinoma cells, specifically HepG2, and SNU-182 cells. Methanolic MIE impaired the proliferation, and induced cell death in both HepG2 and SNU-182 cells but not in normal hepatic L-02 cells. Mechanistically, flow cytometric analysis revealed that MIE induces apoptosis in HepG2, and SNU-182 cells. However, MIE-induced apoptosis were not affected by a pan caspase inhibitor z-VAD-fmk as well as MIE did not stimulate caspase activation. Furthermore we found that MIE-induced apoptosis could be attributed to a mechanism involving mitochondria-mediated pathways evidenced by decrease in the mitochondrial membrane potential (ΔΨm), increase in the Bax/Bcl-2 ratio, and translocation of apoptosis inducing factor (AIF) from the mitochondria to the nucleus. Suppression in AIF expression by siRNA reduced MIE-induced apoptosis which suggested the dependency of MIE on AIF to induce apoptosis in hepatocellular carcinoma cells. To the best of our knowledge this is the first report elucidating the anticancer mechanism of MIE. Our findings suggested that MIE might be a good extract for developing anticancer drugs for human hepatocellular carcinoma treatment.

The objective of our study is to highlight the therapeutic effect and mechanism of action by which purified Flaxseed hydrolysate (PFH) which is a lignan rich fraction exerts its anticancer activity on a human breast cancer cell line (T47D) and in mice bearing tumor. HPLC analysis of PFH of six flaxseed cultivars had shown that PFH of the cultivar Giza 9 (PFH-G9) contains the highest concentration of SDG (81.64 mg/g). The in vitro cytotoxic potentiality of PFH's of six flaxseed cultivars was screened against a panel of human cancer cell lines. PFH -G9 showed the most significant cytotoxic activity against ER-receptor positive breast cell lines MCF7 and T47D with IC 13.8 and 15.8 µg/ml, respectively. Moreover, PFH-G9 reduced the expression of the metastasis marker, 1-α, metalloproteinases and vascular endothelial growth factor (VEGF), one of the most potent stimulators of angiogenesis, while it increased the caspase-3 dependent apoptosis. Our study also showed that dietary intake of 10% of Giza 9 Flaxseeds (FS), fixed oil (FSO) or Flax meal (FSM) twice daily for 3 weeks in mice-bearing solid Ehrlich ascites carcinoma (EAC) resulted in reducing the tumor volume, the expression of estrogen, insulin growth factor, progesterone, VEGF and MMP-2, but enhanced expression of caspase-3.

The development of checkpoint kinase 2 (Chk2) inhibitors for the treatment of cancer has been an ongoing and attractive objective in drug discovery. In this study, twenty-one feasible pyrazole-benzimidazole conjugates were synthesized to study their effect against Chk2 activity using Checkpoint Kinase Assay. The antitumor activity of these compounds was investigated using SRB assay. A potentiation effect of the synthesized Chk2 inhibitors was also investigated using the genotoxic anticancer drugs cisplatin and doxorubicin on breast carcinoma, (ER+) cell line (MCF-7). In vivo Chk2 and antitumor activities of 8d as a single-agent, and in combination with doxorubicin, were evaluated in breast cancer bearing animals induced by N-methylnitrosourea. The effect of 8d alone and in combination with doxorubicin was also studied on cell-cycle phases of MCF-7 cells using flow cytometry analysis. The results revealed their potencies as Chk2 inhibitors with IC ranges from 9.95 to 65.07 nM. Generally the effect of cisplatin or doxorubicin was potentiated by the effect of most of the compounds that were studied. The in vivo results indicated that the combination of 8d and doxorubicin inhibited checkpoint kinase activity more than either doxorubicin or 8d alone. There was a positive correlation between checkpoint kinase inhibition and the improvement observed in histopathological features. Single dose treatment with doxorubicin or 8d produced S phase cell cycle arrest whereas their combination created cell cycle arrest at G2/M from 8% in case of doxorubicin to 51% in combination. Gold molecular modelling studies displayed a high correlation to the biological results.

Activated checkpoint kinase 2 (Chk2) is a tumor suppressor as one of the main enzymes that affect the cell cycle. 2-Biarylbenzimidazoles are potent selective class of Chk2 inhibitors; the structure-based design was applied to synthesize a new series of this class with replacing the lateral aryl group by substituted pyrazoles. Ten pyrazole-benzimidazole conjugates from the best fifty candidates according to docking programs have been subjected to chemical synthesis in this study. The activities of the conjugates 5-14 as checkpoint kinase inhibitors and as antitumor alone and in combination with genotoxic drugs were evaluated. The effect of compounds 7 and 12 on cell-cycle phases was analyzed by flow cytometry analysis. Antitumor activity of compounds 7 and 12 as single-agents and in combinations with doxorubicin was assessed in breast cancer bearing animals induced by MNU. The Results indicated that compounds 5-14 inhibited Chk2 activity with high potency (IC 52.8 nM-5.5 nM). The cytotoxicity of both cisplatin and doxorubicin were significantly potentiated by the most of the conjugates against MCF-7 cell lines. Compounds 7 and 12 and their combinations with doxorubicin induced the cell cycle arrest in MCF-7 cells. Moreover, compound 7 exhibited marked higher antitumor activity as a single agent in animals than it's combination with doxorubicin or doxorubicin alone. The combination of compound 12 with doxorubicin was greatly effective on animal than their single-dose treatment. In conclusion, pyrazole-benzimidazole conjugates are highly active Chk2 inhibitors that have anticancer activity and potentiate activity of genotoxic anticancer therapies and deserve further evaluations.

Recently a dramatic development of the cancer drug discovery has been shown in the field of targeted cancer therapy. Checkpoint kinase 2 (Chk2) inhibitors offer a promising approach to enhance the effectiveness of cancer chemotherapy. Accordingly, in this study many pyrimidine-benzimidazole conjugates were designed and twelve feasible derivatives were selected to be synthesized to investigate their activity against Chk2 and subjected to study their antitumor activity alone and in combination with the genotoxic anticancer drugs cisplatin and doxorubicin on breast carcinoma, (ER+) cell line (MCF-7). The results indicated that the studied compounds inhibited Chk2 activity with high potency (IC = 5.56 nM - 46.20 nM). The studied candidates exhibited remarkable antitumor activity against MCF-7 (IG = 6.6  μM - 24.9 μM). Compounds 10a-c, 14 and 15 significantly potentiated the activity of the studied genotoxic drugs, whereas, compounds 9b and 20-23 antagonized their activity. Moreover, the combination of compound 10b with cisplatin revealed the best apoptotic effect as well as combination of compound 10b with doxorubicin led to complete arrest of the cell cycle at S phase where more than 40% of cells are in the S phase with no cells at G2/M. Structure-activity relationship was discussed on the basis of molecular modeling study using Molecular modeling Environment program (MOE).

AIMS: Novel series of N-(4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl) cyanoacetamide derivatives are synthesized.

METHOD: The structure of these compounds was elucidated using different spectral tools. Compounds were evaluated for their cytotoxic activities against different types of human cancer cell lines including, breast (MCF-7, T47D, MDA MB231); liver (HEPG-2); colon (HCT116); prostate (PC3); and cervix (HELA) cells. In this study, we used compounds 11 and 12 that showed the highest cytotoxicity on PC3 and HEPG2 cells, to explore their effects on apoptosis, metastasis and angiogenesis of cancer cells.

RESULTS: Results revealed that the growth inhibition produced by the two selected compounds was due to cytocidal and not due to cytostatic effect in both cell lines. This cytocidal effect was due to up-regulation of caspases-3, and- 9. In addition, the two compounds inhibited the expression of metalloproteinases-2 and 9 (MMP 2&9). Moreover, HIF-1alpha and VEGF expressions were inhibited by both compounds.

CONCLUSION: In conclusion, N-(4, 5, 6, 7-tetrahydrobenzo[b]thiophen-2-yl) cyanoacetamide derivatives showed different anticancer potential against different cancer cell lines. Compounds 11 and 12 showed the most active cytotoxicity against PC3 and HepG2 cells. Both compounds have apoptotic, anti- metastatic and anti-angiogenic effects.

BACKGROUND: Colorectal cancer (CRC) remains a leading cause of death worldwide. Utilizing cisplatin in CRC is correlated with severe adverse effects and drug-resistance. Combined anticancer drug-treatment, along with, their enhanced delivery, can effectively kill cancer through multiple pathways. Nano-cubosomes are emerging as nanocarriers for anticancer therapies, hence, we constructed nano-cubosomes bearing cisplatin and cisplatin-metformin combination for investigation on HCT-116 cells.

METHODS: Nano-cubosomes bearing either cisplatin alone or cisplatin-metformin combination were formulated using emulsification technique. The loaded nano-cubosomes were characterized in vitro and the optimized formulation was selected. Their cytotoxic effects were investigated by Sulphorhodamine-B (SRB) assay. The AMPK/mTOR metabolic pathway as well as the Akt/mTOR pathway were analyzed using ELISA technique. Colorimetry was used in NADPH oxidase, LDH and caspase-3 activity determination.

RESULTS: nano-cubosomal formulations exhibited superior cytotoxic effect compared to unformulated cisplatin. This cytotoxic effect was profound upon incorporation of metformin, an indirect mTOR inhibitor, in cisplatin nano-cubosomes. The induced CRC cell apoptosis was through inhibition of several metabolic pathways, namely, AMPK/mTOR and Akt/mTOR. Drug-loaded nano-cubosomes ensued depletion in glucose and energy levels that led to AMPK activation and thus mTOR inhibition. mTOR was additionally inhibited via suppression of p-Akt (Ser473) levels after nano-cubosomal treatment. Moreover, drug-loaded nano-cubosomes produced a notable escalation in ROS levels, evident as an increase in NADPH oxidase, inhibition of LDH and a consequential upsurge in caspase-3.

CONCLUSION: These results demonstrated the influence exerted by cisplatin-loaded nano-cubosomes on CRC cell survival and enhancement of their cytotoxicity upon metformin addition.

A green method was used for producing gold nanoparticles (Au NPs) using chitosan as a natural cationic, biodegradable and biocompatible polymer. In this method, chitosan acts as a reducing and stabilizing agent for the synthesis of Au NPs. Different concentrations of chitosan solutions (0.01%, 0.05%, 0.1%, 0.2%, 0.5% and 1%) were applied. In an attempt to mitigate the side effects of anti-cancer drug, 5-fluorouracil (5-FU), through reducing drug doses in photothermal therapy, the formed positively-charged chitosan-wrapped Au NPs were used as a drug delivery system for negatively charged 5-FU to hepatocellular carcinoma cells (HepG2). Au NPs as well as 5-FU@Au nanocomposites were characterized with UV-VIS spectroscopy, particle size, zeta potential, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and High-Performance Liquid Chromatography (HPLC). The chitosan concentration was shown to be an important parameter for optimizing the dispersion of Au NPs and 5-FU@Au nanocomposites over long time. This stability offers the 5-FU@Au nanocomposites as good candidate for cancer treatment with reduced drug doses in photothermal therapy. A 72% loading-efficiency of 5-FU was obtained. Cytotoxic assay was carried out on HepG2 cell line and it reveals the effectiveness of 5-FU@Au nanocomposites in the presence and absence of laser irradiation compared with the free 5-FU. The cytotoxicity effect of free 5-FU and 5-FU@AuNPs nanocomposites was studied, and it was found that the concentration of 5-FU@Au nanocomposites required to attain 50% of inhibition growth rate was lower than that of free 5-FU in absence of laser radiation and was much lower in presence of laser radiation.

Selenium and its derivatives including sodium selenite (sod sel) belong to the group of essential trace elements needed for proper health and nutrition. They are fairly safe and possess antioxidant and anti-inflammatory properties. The aim of present investigation was to elucidate the effect of sod sel on experimental colitis model in rats. Colitis was induced by intrarectal instillation of 4% (v/v) acetic acid. Two hours later, sod sel was given to rats on a daily basis for 15 consecutive days. Clinical symptoms, colon mass index, spleen weight inflammatory markers, hematological, biochemical, macroscopic, and histological changes were determined. Sod sel markedly ameliorated colitis as evidenced by a significant decrease in macroscopic and microscopic score, disease activity index, colon mass index, and spleen weight. Treatment with sod sel attenuated oxidative stress in the colon by normalizing the colonic content of nitric oxide, malondialdehyde, and reduced glutathione, as well as the activities of catalase, superoxide dismutase, and junctional adhesion molecule (JAM-a). In addition, it significantly reduced colonic myeloperoxidase content, the intercellular adhesion molecule (ICAM-1), and the proinflammatory cytokines; TNF-α, IL-1β. Moreover, sod sel normalized hematological parameters, serum transaminases, and kidney and liver function enzymes. The current study indicates that sod sel was effective in ameliorating the intestinal and extra-intestinal manifestation in acetic acid-induced colitis through its antioxidant, anti-inflammatory, and immunomodulatory effects.