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Inhibition of suppressor T lymphocytes (Ts) by cimetidine. Sahasrabudhe DM, McCune CS, O'Donnell RW, Henshaw EC. J Immunol. 1987 May 1;138(9):2760-3. PMID: 2952721 Cyclophosphamide (CY) is the most extensively studied inhibitor of suppressor T lymphocyte (Ts) function. However, repeated administration of CY can abrogate sensitization. Therefore, we were interested in identifying noncytotoxic inhibitors of Ts function as adjuncts in the immunotherapy of Ts-inducing murine tumors. The effect of cimetidine (a histamine type 2 receptor antagonist) and diphenhydramine (a histamine type 1 receptor antagonist) on the Ts mediating tolerance to 2,4-dinitrofluorobenzene was studied. We report our data regarding the specific inhibition of Ts by cimetidine.

Derived from the bulb or clove of the plant. Garlic is used as a spice and to treat hyperlipidemia, hypertension, atherosclerosis, cancer, and infections. Processing can have a substantial effect on the chemical content in garlic; the volatile oil components are sensitive to heat and certain enzymes are acid-labile. Several oral garlic formulations are available, and clinical studies have addressed a variety of the proposed claims. Placebo-controlled trials on the cholesterol lowering effect of garlic yielded mixed results (16) (17) (18) (21) (22) (26). Studies evaluating the antithrombotic effects repeatedly have shown modest reduction in platelet aggregation, but varying levels of fibrinolytic activity. Research shows mixed effects with regard to reductions in blood glucose, blood pressure, or risk of cardiovascular disease (23). Frequently reported adverse events include bad breath, headache, fatigue, GI upset, diarrhea, sweating, and possible hypoglycemia (9). Because garlic is known to decrease platelet aggregation and potentially elevate the INR, it should not be used with anticoagulants or in patients with platelet dysfunction (15). Garlic appears to induce cytochrome p450 3A4 and may enhance metabolism of many medications (e.g. cyclosporin and saquinavir) (12). An analysis of several case-control studies in Europe suggests an inverse association between garlic consumption and risk of common cancers (25).

ScienceDaily (June 11, 2009) - University of Florida researchers have come up with a new gene therapy method to disrupt cancer growth by using a synthetic protein to induce blood clotting that cuts off a tumor's blood and nutrient supply. In mice implanted with human colorectal cancer cells, tumor volume decreased 53 percent and cancer cell growth slowed by 49 percent in those treated with a gene that encodes for the artificial protein, compared with those that were untreated.

Derived from the cap and stem of the mushroom, Reishi mushroom is used as an immune stimulant by patients with HIV or cancer. The active constituents are thought to include both beta-glucan polysaccharides and triterpenes (1). Extracts of Reishi can stimulate macrophages and alter the levels of TNF and interleukins (2) (3) (4) (5). Reishi also inhibited platelet aggregation (11) (12) and improved lower urinary tract symptoms (LUTS) in men (9) (10). Studies done in rats have shown that Reishi extract may alleviate chemotherapy-induced nausea (13). In clinical studies, Reishi increased plasma antioxidant capacity (6) (7)and enhanced immune responses in advance-stage cancer patients (8).

A proprietary extract prepared from co-cultured mycelia of several species of Basidiomycete mushrooms, including shiitake (Lentinus edodes), active hexose correlated compound (AHCC) is extracted from mushrooms using hot water following an enzyme pretreatment, but specific mushroom source and preparation details have not been fully disclosed. Patients use this to prevent and treat cancer. Animal studies suggest that AHCC has antioxidant effects and may protect against disorders induced by oxidative stress (1) and may also enhance resistance against bacterial (2) (7)and viral infections (3). In healthy humans, AHCC increased dendritic cell number and function (4) In vitro and animal studies show that AHCC exhibits some anticancer activities, but the results of these studies are vague

Induction of ovarian cancer cell apoptosis by 1,25-dihydroxyvitamin D3 through the down-regulation of telomerase. Jiang F, Bao J, Li P, Nicosia SV, Bai W. J Biol Chem. 2004 Dec 17;279(51):53213-21. Epub 2004 Oct 12. PMID: 15485861 doi: 10.1074/jbc.M410395200 Overall, the study suggests that the down-regulation of telomerase activity by 1,25(OH)2VD3 and the resulting cell death are important components of the response of OCa cells to 1,25(OH)2VD3-induced growth suppression. Progressive shortening of telomere associated with cell divisions limits the life span of normal cells and eventually leads to senescence. To become immortal, human cancers including OCa are invariably associated with activation of mechanism that maintains telomere length. Approximately 85-90% of cancers show reactivation of telomerase. The present study shows that telomerase in OCa cells is down-regulated by 1,25(OH)2VD3. Down-regulation of telomerase is due to decreased stability of hTERT mRNA rather than VDRE-mediated transcriptional repression through the putative VDRE present in the regulatory region of the hTERT gene. It is known that the inhibition of telomerase may lead to a phenotypic lag during which cells would continue to divide until the point at which the telomeres became critically short. This phenomenon may explain why the apoptotic induction by 1,25(OH)2VD3 needs the treatment for more than 6 days. As mentioned in the results, no detectable shortening of telomeric repeats was observed in parental OVCAR3 cells after 9 days of treatment with 1,25(OH)2VD3 (Fig. 4D). This is likely due to the fact that the short telomere (about 3 kb) in OVCAR3 cells is very close to the minimal length required for survival and that cells with detectably shorter telomere may have been selected against apoptosis. It has been shown that transformed human cells enter crisis once the terminal restriction fragment of the telomere reaches a length of about 4 kb. This is insufficient to protect chro