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Tumor resistance is typically blamed for the failure of radiotherapy and chemotherapy to treat cancer in clinic patients. To improve the cytotoxicity of tumor cells using radiation in conjunction with specific tumor-selective cytotoxic drugs is crucial. Pomegranate has received overwhelmingly positive feedback as a highly nutritious food for enhancing health and treating a variety of ailments. In the present study, we aimed to examine the effects as well as mechanism of action of pomegranate peel extract (PPE) and/or γ-radiation (6-Gy) on hepatocellular carcinoma (HCC) cell lines HepG2. The findings of this study showed that PPE treatment of HepG2 cells considerably slowed the proliferation of cancer cells, and its combination with γ-irradiation potentiated this action. As a key player in tumor proliferation, and inflammatory cascade induction, the down-regulation of STAT3 following treatment of irradiated and non-irradiated HepG2 cells with PPE as recorded in the present work resulted in reduction of tumor growth, via modulating inflammatory response manifested by (down-regulation of TLR4 expression and NFKB level), suppressing survival markers expressed by reduction of JAK, NOTCH1, ß-catenin, SOCS3, and enhancing apoptosis (induction of tumor PPAR-γ and caspase-3) followed by changes in redox tone (expressed by increase in Nrf-2, SOD and catalase activities, and decrease in MDA concentration). In conclusion, PPE might possess a considerable therapeutic potential against HCC in addition to its capability to enhance response of HepG2 cells to gamma radiation.

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BACKGROUND: Colorectal cancer (CRC) is one of the most common types of cancer worldwide and the second cause of cancer-related deaths. It usually starts as an inflammation that progresses to adenocarcinoma. The goal of the present study was to investigate the antitumor efficacy of a new thiophene derivative against CRC in mice and explore the possible associated molecular pathways. The potential of this thiophene derivative to sensitize the CRC tumor tissue to a low dose of gamma irradiation was also investigated. METHODS: Adult male mice were divided into seven groups; control, group treated with dimethylhydrazine (DMH) for the induction of CRC. The DMH-group was further divided into six groups and treated with either cisplatin, thiophene derivative, γ-irradiation, cisplatin + γ-irradiation, thiophene derivative + γ-irradiation, or left untreated. RESULTS: DMH induced CRC as evidenced by the macroscopic examination of colon tissues and histopathology, and elevated the activities of cyclooxygenase2 (COX2) and nitric oxide synthase (iNOS). DMH also elevated kirsten rat sarcoma (KRAS) and downregulated the peroxisome proliferator activated receptor (PPARγ) as shown by RT-PCR and Western blotting. DMH exerted anti-apoptotic activity by reducing the expression of phosphorylated p53 and cleaved caspase3 at the gene and protein levels. The flow cytometry analysis showed that DMH elevated the necrosis and reduced the apoptosis compared to the other groups. The colon tissue from DMH-treated mice showed hyperplasia, aberrant crypt foci, loss of cell polarity, typical CRC of grade 4 with lymphocytes and macrophages infiltrating mucosa, muscularis mucosa, and submucosa score 3. Treatment with thiophene derivative or γ-irradiation ameliorated most of these deleterious effects of DMH. The concomitant action of thiophene derivative + γ-irradiation was typified by the better amelioration of tumor incidence and multiplicity, iNOS, PPARγ, p53, caspase 3, and histopathology of colon. CONCLUSION: Taken together, the new thiophene derivative is a promising therapeutic candidate for treatment of colorectal cancer in mice. It also sensitizes the CRC tumor to the ionizing radiation through anti-inflammatory and pro-apoptotic pathways.

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Background: MicroRNAs (miRs) are small (19-25 nucleotides), non-protein coding RNAs that regulate gene expression, and thus play essential roles in cell cycle progression. The evidence has demonstrated that the expression of several miRs is dysregulated in human cancer. Methods: The study includes 179 female patients and 58 healthy women Patients were identified as luminal A, B, Her-2/neu, and basal-like, as well as classified into I, II, and III stages. Analysis of the expression fold change of miR-21 and miR-34a with molecular markers, including the oncogene Bcl-2 (B-cell lymphoma 2) and the tumor suppressor genes BRCA1 (breast cancer susceptibility gene 1), BRCA2 (breast cancer susceptibility gene 2), and the tumor suppressor protein p53, was carried out for all patients, pre- and post-chemotherapy, and for all healthy women. Results: At diagnosis (pre-chemotherapy), miR-21 was up-regulated (p < 0.001), while miR-34a was down-regulated (p < 0.001). Post-chemotherapy, the expression of miR-21 decreased significantly (p < 0.001), while the expression of miR-34a increased significantly (p < 0.001). Conclusion: miR-21 and miR-34a may be helpful to non-invasive biomarkers to evaluate the response of breast cancer to chemotherapy.

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PURPOSE: Pathological angiogenesis and apoptosis evasions are common hallmarks of cancer. A different approach to the antitumor effect of parasitic diseases caused by certain protozoans and helminthes had been adopted in recent years as they can affect many cancer characteristics. The present work is an attempt to assess the effect of gamma radiation-attenuated Toxoplasma gondii ME49 as an antiapoptotic and angiogenic regulator modifier on tumor growth aimed at improving cancer protective protocols. METHODS: Attenuated Toxoplasma gondii ME49 was administered orally to mice 2 weeks before inoculation with Ehrlich ascites carcinoma to allow stimulation of the immune response. Hepatic histopathology and immune responses were determined for each group. RESULTS: Marked suppression of the tumor proliferation with induction of long-lasting immunity by stimulating interferon γ and downregulating transforming growth factor ß. The level of tumor promoting inflammatory markers (STAT-3 and tumor necrosis factor α), the angiogenic factors (vascular endothelial growth factor A, integrin, and matrix metallopeptidase 2 and matrix metallopeptidase 9), as well as nitric oxide concentration were significantly decreased. This was collimated with an improvement in apoptotic regulators (cytochrome-c, Bax, Bak, and caspase 3) in liver tissues of vaccinated mice group compared to Ehrlich ascites carcinoma-bearing one. Moreover, the histopathological investigations confirmed this improvement. CONCLUSION: Hence, there is an evidence of potency of radiation attenuated Toxoplasma vaccine in immune activation and targeting tumor cell that can be used as a prophylactic or an adjuvant in combination with chemotherapeutic drugs.

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