Comparison of caspase-3 activation in tumor cells upon treatment of chemotherapeutic drugs using capillary electrophoresis

Crystal structure and chemotherapeutic efficacy of the novel compound, gallium tetrachloride betaine, against breast cancer using nanotechnology

The objective of this study was to investigate the antitumor efficacy of a novel synthesized compound, betaine gallium-tetrachloride (BTG), alone or combined with ZnO-nanoparticles (BTG + ZnO-NPs) on the incidence of 7, 12-dimethylbenz-anthrathene-induced mammary tumor in female rats. Crystal and molecular structure of the prepared BTG were identified using X-ray crystallography. In vitro study revealed BTG more cytotoxic than BTG + ZnO-NPs on human breast cancer (MCF-7) cell line. In vivo study demonstrated that the blood antioxidant status of tumor-bearing rats (DMBA group) was significantly lower than normal noticeable by a significant decrease in GSH content, GPx, SOD, and CAT activities associated with a significantly high MDA content. Both treatments have significantly elevated SOD and CAT activities with a concomitant decrease of MDA level compared to DMBA group. However, BTG + ZnO-NPs accentuated the decrease of GSH regarding DMBA group. The results showed also that both treatments significantly activate caspase-3 enzyme and apoptosis in mammary glands. Their administration to tumor-bearing rats was found to significantly reduce plasma iron and iron-binding capacity (TIBC) compared to DMBA group. Regarding liver function, both treatments significantly reduced the increase of ALT and AST activities compared to DMBA group. However, BTG + ZnO-NPs decreased albumin below normal level. Histopathological studies showed that normalization of tissue structures was higher in BTG than BTG + ZnO-NPs treatment. According to the results obtained, it is observed that the antitumor effect of BTG alone was as strong as BTG + ZnO-NPs and even more efficient in some aspects accordingly, a combination is not needed. Thus, the novel synthetic gallium derivatives may potentially present a new hope for the development of breast cancer therapeutics, which should attract further scientific and pharmaceutical interest.

Synergistic efficacy of γ-radiation together with gallium trichloride and/or doxorubicin against Ehrlich carcinoma in female mice

Combining chemotherapy with radiotherapy represents a key oncology strategy for a more comprehensive attack toward cancers and improves treatment outcome for various solid tumor malignancies. The present study aims to evaluate the synergistic antitumor effect of γ-radiation together with gallium trichloride (GaCl3) and/or doxorubicin (DOX) against solid Ehrlich carcinoma (EC) in female mice. GaCl3 (300 mg/kg body weight (b.w.)) was administered by gavages daily on the seventh day after tumor inoculation, while the cytotoxic drug DOX (4 mg/kg b.w.) was administered intraperitoneally once a week. Whole-body γ-radiation was carried out at a dose 2 Gy once a week. Biochemical analysis showed that solid EC induced a significant increase in malondialdehyde (MDA) content with a significant decrease in the antioxidant state (glutathione peroxidase (GPx) and catalase (CAT) activities) and depleted serum iron concentration compared to normal control. Moreover, a significant increase was observed in calcium level and caspase-3 concentrations in both serum and tumor homogenate respectively associated with a significant alteration in heart, liver, and kidney functions, as compared to control. Treatment of EC-bearing mice with GaCl3and/or DOX combined with γ-radiation exposure significantly reduced tumor volume and displayed a significant improvement in most studied markers which may indicate a synergistic effect of this combination against organ dysfunction and cellular injury. The histopathologically investigation showed that treatment of animals bearing EC with GaCl3and/or DOX with γ-radiation exposure showed shrinkage in tumor lesions and wide zones of apoptotic cells with signs of regenerations. It was concluded that the combination of GaCl3and/or DOX with γ-radiation exposure resulted in super-additive cytotoxic effects on treatment of cancer cells.

TNFR-1 on tumor cells contributes to the sensitivity of fibrosarcoma to chemotherapy

Impaired tumor necrosis factor receptor-1 (TNFR-1) signaling has been found in some malignant tumors with poor prognosis. However, the exact role of TNFR-1 signaling in fibrosarcoma remains unclear. Here, we explored the question by comparing the growth of TNFR-1 deficient (Tnfr1 (-)) and TNFR-1 competent (Tnfr1 (+)) fibrosarcoma FB61 cells (FB61-m and FB61-R1) in mice. TNFR-1 expression on fibrosarcoma cells delayed their growth in vivo but not in vitro. Moreover, reduced FB61-R1 tumor growth was also obtained in TNFR-1 knockout mice. The mechanism relies mainly on the TNFR-1-mediated downregulation of vascular endothelial growth factor (VEGF) production by tumor cells. Importantly, treatment of FB61-m tumors with melphalan resulted in a short delay of tumor growth, followed by a quick remission. However, when FB61-R1 tumors were treated with melphalan, tumor growth was similarly delayed at first and then completely rejected. Our results reveal evidence for TNFR-1 on tumor cells as a prerequisite in chemotherapy for fibrosarcoma, and provide novel insight into the therapeutic approach against some types of tumors using TNFR-1 angonist.