ascorbic-acid and Carcinoma--Lewis-Lung

Topics: Animals; Antineoplastic Agents; Antioxidants; Ascorbic Acid; Carcinoma, Lewis Lung; Drug Administration Schedule; Female; Gene Expression Regulation, Neoplastic; Hypoxia-Inducible Factor 1, alpha Subunit; Injections, Intraperitoneal; Isoenzymes; Mice; Mice, Knockout; Signal Transduction; Sodium-Coupled Vitamin C Transporters; Vascular Endothelial Growth Factor A

Hypoxia-inducible factor-1 (HIF-1) governs cellular adaption to the hypoxic microenvironment and is associated with a proliferative, metastatic, and treatment-resistant tumor phenotype. HIF-1 levels and transcriptional activity are regulated by proline and asparagine hydroxylases, which require ascorbate as cofactor. Ascorbate supplementation reduced HIF-1 activation in vitro, but only limited data are available in relevant animal models. There is no information of the effect of physiological levels of ascorbate on HIF activity and tumor growth, which was measured in this study. C57BL/6 Gulo(-/-) mice (a model of the human ascorbate dependency condition) were supplemented with 3300 mg/L, 330 mg/L, or 33 mg/L of ascorbate in their drinking water before and during subcutaneous tumor growth of B16-F10 melanoma or Lewis lung carcinoma (LL/2). Ascorbate levels in tumors increased significantly with elevated ascorbate intake and restoration of wild-type ascorbate levels led to a reduction in growth of B16-F10 (log phase P < 0.001) and LL/2 tumors (lag growth P < 0.001, log phase P < 0.05). Levels of HIF-1α protein in tumors decreased as dietary ascorbate supplementation increased for both tumor models (P < 0.001). Similarly, tumor ascorbate was inversely correlated with levels of the HIF-1 target proteins CA-IX, GLUT-1, and VEGF in both B16-F10 and LL/2 tumors (P < 0.05). The extent of necrosis was similar between ascorbate groups but varied between models (30% for B16-F10 and 21% for LL/2), indicating that ascorbate did not affect tumor hypoxia. Our data support the hypothesis that restoration of optimal intracellular ascorbate levels reduces tumor growth via moderation of HIF-1 pathway activity.

Topics: Animals; Ascorbic Acid; Carcinoma, Lewis Lung; Cell Proliferation; Disease Models, Animal; Dose-Response Relationship, Drug; Gene Expression Regulation, Neoplastic; Glucose Transporter Type 1; Hypoxia-Inducible Factor 1, alpha Subunit; Melanoma, Experimental; Mice; Mice, Inbred C57BL; Mice, Transgenic; Signal Transduction; Vitamins

Vitamin C (vit C) has been shown to diminish cisplatin (CP)-induced nephrotoxicity and oxidative damage in healthy rats and mice. However, little is known whether vit C has similar actions and enhances the anticancer effect of CP in tumor-bearing mice. Herein, C57BL/6 mice were implanted (s.c.) with Lewis lung carcinoma (LLC) for 9 days before intraperitoneal administration with CP (5 mg/kg) in the presence or absence of low- (200 mg/kg) and high- (1000 mg/kg) dose vit C twice a week for an additional 28 days. Results reveal that vit C or CP treatment alone significantly inhibited tumor growth, although vit C in combination with CP did not further inhibit tumor growth, as compared to CP treatment alone. In addition, CP significantly induced nephrotoxicity and oxidative damage, as evidenced by increased plasma levels of blood urea nitrogen and creatinine as well as levels of lipid peroxidation and carbonyls, decreased ratios of GSH/GSSG in liver and kidney. Vit C significantly reversed these undesirable side effects induced by CP, and most of these actions of vit C were dose-dependent. Overall, we conclude that vit C can protect against CP-induced nephrotoxicity and damage without reducing CP's effectiveness in LLC-bearing mice.

Topics: Animals; Antineoplastic Agents; Ascorbic Acid; Blood Urea Nitrogen; Carcinoma, Lewis Lung; Cell Line, Tumor; Cisplatin; Creatinine; Glutathione; Kidney; Kidney Diseases; Lipid Peroxidation; Liver; Male; Mice; Mice, Inbred C57BL; Oxidative Stress; Protein Carbonylation; Xenograft Model Antitumor Assays

Indoleamine 2,3-dioxygenase (IDO-1) is emerging as an important new therapeutic target for the treatment of cancer, neurological disorders, and other diseases that are characterized by pathological tryptophan metabolism. However, only a few structural classes are known to be IDO-1 inhibitors. In this study, a natural compound tryptanthrin was discovered to be a novel potent IDO-1 inhibitor by screening of indole-based structures. Three series of 13 tryptanthrin derivatives were synthesized, and the structure-activity analysis was undertaken. The optimization led to the identification of 5c, which exhibited the inhibitory activity at a nanomolar level. In vitro 5c dramatically augmented the proliferation of T cells. When administered to Lewis lung cancer (LLC) tumor-bearing mice, 5c significantly inhibited IDO-1 activity and suppressed tumor growth. In addition, 5c reduced the numbers of Foxp3(+) regulatory T cells (Tregs), which are known to prevent the development of efficient antitumor immune responses.

Topics: Animals; Antineoplastic Agents; Carcinoma, Lewis Lung; Dose-Response Relationship, Drug; Drug Discovery; Enzyme Inhibitors; Humans; Indoleamine-Pyrrole 2,3,-Dioxygenase; Lung Neoplasms; Mice; Molecular Structure; Quinazolines; Structure-Activity Relationship; Xenograft Model Antitumor Assays

β-Glucans are naturally occurring carbohydrates found in plants, fungi and some bacterial species, and currently are well-established and powerful immunomodulators with beneficial properties in cancer therapy. Recent studies suggested that some additional bioactive molecules have synergistic effects when combined with glucan. In the current study, we evaluated the anticancer properties of glucan, resveratrol, vitamin C combination. We found that compared to the individual components, the combination was the strongest activator of phagocytosis and antibody formation. Using two different models of cancer treatment, our results demonstrated that the combination strongly suppressed the growth of breast and lung tumors, most likely due to the stimulation of apoptosis.

Topics: Animals; Antibody Formation; Antioxidants; Ascorbic Acid; beta-Glucans; Carcinoma, Lewis Lung; Drug Therapy, Combination; Female; Granulocytes; Immunologic Factors; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Ovalbumin; Phagocytosis; Resveratrol; Stilbenes

Vitamin C in combination with vitamin K3 (vit CK3) has been shown to inhibit tumor growth and lung metastasis in vivo, but the mechanism of action is poorly understood. Herein, C57BL/6 mice were implanted (s.c.) with Lewis lung carcinoma (LLC) for 9 days before injection (i.p.) with low-dose (100 mg vit C/kg + 1 mg vit K3/kg), high-dose (1,000 mg vit C/kg + 10 mg vit K3/kg) vit CK3 twice a week for an additional 28 days. As expected, vit CK3 or cisplatin (6 mg/kg, as a positive control) significantly and dose-dependently inhibited tumor growth and lung metastasis in LLC-bearing mice. Vit CK3 restored the body weight of tumor-bearing mice to the level of tumor-free mice. Vit CK3 significantly decreased activities of plasma metalloproteinase (MMP)-2, -9, and urokinase plasminogen activator (uPA). In lung tissues, vit CK3 1) increased protein expression of tissue inhibitor of metalloproteinase-1 (TIMP-1), TIMP-2, nonmetastatic protein 23 homolog 1 and plasminogen activator inhibitor-1; 2) reduced protein expression of MMP-2 and MMP-9; and 3) inhibited the proliferating cell nuclear antigen (PCNA). These results demonstrate that vit CK3 inhibits primary tumor growth and exhibits antimetastastic potential in vivo through attenuated tumor invasion and proliferation.

Topics: Animals; Ascorbic Acid; Blotting, Western; Carcinoma, Lewis Lung; Cell Line; Cell Line, Tumor; Cell Proliferation; Cisplatin; Dose-Response Relationship, Drug; Lung Neoplasms; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mice; Mice, Inbred C57BL; Neoplasm Invasiveness; Plasminogen Activator Inhibitor 1; Tissue Inhibitor of Metalloproteinase-1; Tissue Inhibitor of Metalloproteinase-2; Transplantation, Heterologous; Urokinase-Type Plasminogen Activator; Vitamin K 3

Angiogenesis requires the deposition of type IV collagen by endothelial cells into the basement membrane of new blood vessels. Stabilization of type IV collagen triple helix depends on the hydroxylation of proline, which is catalyzed by the iron-containing enzyme prolyl hydroxylase. This enzyme, in turn, requires ascorbic acid to maintain the enzyme-bound iron in its reduced state. We hypothesized that dietary ascorbic acid might be required for tumor angiogenesis and, therefore, tumor growth. Here, we show that, not surprisingly, ascorbic acid is necessary for the synthesis of collagen type IV by human endothelial cells and for their effective migration and tube formation on a basement membrane matrix. Furthermore, ascorbic acid depletion in mice incapable of synthesizing ascorbic acid (Gulo(-/-)) dramatically restricts the in vivo growth of implanted Lewis lung carcinoma tumors. Histopathological analyses of these tumors reveal poorly formed blood vessels, extensive hemorrhagic foci, and decreased collagen and von Willebrand factor expression. Our data indicate that ascorbic acid plays an essential role in tumor angiogenesis and growth, and that restriction of ascorbic acid or pharmacological inhibition of prolyl hydroxylase may prove to be novel therapeutic approaches to the treatment of cancer.

Topics: Animals; Ascorbic Acid; Carcinoma, Lewis Lung; Cell Movement; Cells, Cultured; Collagen Type IV; Disease Models, Animal; Endothelial Cells; Humans; L-Gulonolactone Oxidase; Mice; Mice, Inbred C57BL; Neovascularization, Pathologic; Procollagen-Proline Dioxygenase

The anticancer activity of omega-3 polyunsaturated fatty acids (omega-3 PUFA) has been shown in a large number of studies. This study was undertaken to analyze the combined effect of omega-3 PUFA and antioxidative vitamins on the level of spontaneous metastatic dissemination. The supportive effect of this dietary combination on chemotherapy with cisplatin (CP) was determined in parallel.. C57BL/6J mice bearing the Lewis lung carcinoma 3LL were fed ad libitum one of three isocaloric diets containing 5% soybean oil supplemented with 40 mg/kg alpha-tocopherol acetate (SO diet), or 4% fish oil plus 1% corn oil, and basal amounts of vitamin E (FO diet) or FO diet supplemented with vitamins E and C (FO+E+C diet). These diets were tested in combination with the conventional cytotoxic agent CP in a series of regimens. Tumor growth, feed consumption, body weight, lung metastasis and lung histology were followed.. Both the FO dietary groups showed significantly lower tumor development than the SO group in all examined parameters, indicating that omega-3 PUFA have anticancer activity. However, the FO diet, in comparison with the FO+E+C diet induced a significantly slower rate of tumor growth, and lower metastatic load, as reflected in lung weight. The decrease in the anticancer activity of FO by the addition of vitamins E and C suggests that in situ oxidation of omega-3 PUFA underlies their anticancer action. It is thus proposed that oxidized omega-3 PUFA accumulates in the membranes and the cytosol of tumor cells, reducing their vitality and eventually leading to their death. No signs of anorexia or cachexia were observed in either FO group, in contrast to the SO group. CP treatment with the SO diet had no apparent therapeutic effect, while with the FO diets it reduced the metastatic load. The best regimen of this combined treatment was FO diet followed by CP treatment with FO diet supplemented with vitamins E and C after resection of the primary growth. This regimen could be translated to a combined therapy for human cancer.. Diets enriched with omega-3 PUFA may have beneficial anticancer effects in particular when containing only basal amounts of antioxidants such as vitamin E or C. Furthermore, the addition of drugs which promote oxidation of omega-3 PUFA, such as ferrous salts (e.g. as prescribed for the treatment of anemia), may further increase these effects. However, the supportive effect of omega-3 PUFA in chemotherapy (e.g. with CP) increases when vitamins E and C are also included.

Topics: Analysis of Variance; Animals; Antineoplastic Agents; Ascorbic Acid; Carcinoma, Lewis Lung; Cisplatin; Combined Modality Therapy; Drug Screening Assays, Antitumor; Fatty Acids, Omega-3; Female; Mice; Mice, Inbred C57BL; Soybean Oil; Vitamin E