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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

Glucose restriction can extend normal cell lifespan and impair precancerous cell growth through epigenetic control of hTERT and p16 expression. Li Y, Liu L, Tollefsbol TO. FASEB J. 2009 Dec 17. [Epub ahead of print] PMID: 20019239 doi: 10.1096/fj.09-149328 Cancer cells metabolize glucose at elevated rates and have a higher sensitivity to glucose reduction. However, the precise molecular mechanisms leading to different responses to glucose restriction between normal and cancer cells are not fully understood. We analyzed normal WI-38 and immortalized WI-38/S fetal lung fibroblasts and found that glucose restriction resulted in growth inhibition and apoptosis in WI-38/S cells, whereas it induced lifespan extension in WI-38 cells. Moreover, in WI-38/S cells glucose restriction decreased expression of hTERT (human telomerase reverse transcriptase) and increased expression of p16(INK4a). Opposite effects were found in the gene expression of hTERT and p16 in WI-38 cells in response to glucose restriction. The altered gene expression was partly due to glucose restriction-induced DNA methylation changes and chromatin remodeling of the hTERT and p16 promoters in normal and immortalized WI-38 cells. Furthermore, glucose restriction resulted in altered hTERT and p16 expression in response to epigenetic regulators in WI-38 rather than WI-38/S cells, suggesting that energy stress-induced differential epigenetic regulation may lead to different cellular fates in normal and precancerous cells. Collectively, these results provide new insights into the epigenetic mechanisms of a nutrient control strategy that may contribute to cancer therapy as well as antiaging approaches.

T-helper/T-regulator lymphocyte ratio as a new immunobiological index to quantify the anticancer immune status in cancer patients. Brivio F, Fumagalli L, Parolini D, Messina G, Rovelli F, Rescaldani R, Vigore L, Vezzo R, Vaghi M, Di Bella S, Lissoni P. In Vivo. 2008 Sep-Oct;22(5):647-50. PMID: 18853761 RESULTS: The mean TH/TR ratio observed in patients with metasytases was significantly lower with respect to that found in both patients without metastases and controls. On the contrary, the absolute mean number of T-reg cells was higher in patients with metastases than in those without, but the difference was not statistically significant. CONCLUSION: The evaluation of T-reg cells in terms of their proportion with respect to T-helper cell total number seems to be more appropriate than the simple measurement of their absolute count, in order to quantify cancer-related immunosuppression. Thus, the TH/TR ratio could represent a useful biological marker to explore the immune status of cancer patients.

Cannabinoids inhibit glioma cell invasion by down-regulating matrix metalloproteinase-2 expression. Blázquez C, Salazar M, Carracedo A, Lorente M, Egia A, González-Feria L, Haro A, Velasco G, Guzmán M. Cancer Res. 2008 Mar 15;68(6):1945-52. PMID: 18339876 doi: 10.1158/0008-5472.CAN-07-5176

Berberine inhibits growth, induces G1 arrest and apoptosis in human epidermoid carcinoma A431 cells by regulating Cdki-Cdk-cyclin cascade, disruption of mitochondrial membrane potential and cleavage of caspase 3 and PARP. Mantena SK, Sharma SD, Katiyar SK. Carcinogenesis. 2006 Oct;27(10):2018-27. Epub 2006 Apr 18. PMID: 16621886 doi:10.1093/carcin/bgl043 In the present investigation, we show that berberine, which is present abundantly in Berberis plant species, significantly inhibits the viability, proliferation and induces cell death in human epidermoid carcinoma A431 cells (Figure 1), but this effect was not found in normal human epidermal keratinocytes under the identical conditions, except for a non-significant reduction in cell viability at higher concentrations of berberine (50 and 75 µM) and treatment of cells for a longer period of time (72 h). These data suggested that berberine may be examined as an effective chemotherapeutic agent against non-melanoma skin cancers. In conclusion, our study indicates that berberine inhibits growth, induces G1 arrest and apoptotic cell death of human epidermoid carcinoma A431 cells. We also provide mechanistic evidences that berberine-induced apoptosis in human epidermoid carcinoma cells is mediated through disruption of mitochondrial membrane potential and activation of caspase 3 pathway, although other pathways may have a role and that require further investigation. Moreover, further in vivo studies are required to determine whether berberine could be an effective chemotherapeutic agent for the prevention of non-melanoma skin cancers.

"Worcester, MA - Current research suggests that TNF-receptor associated protein-1 (TRAP-1) may prevent cancer cell death. The related report by Leav et al, "Cytoprotective Mitochondrial Chaperone TRAP-1 as a Novel Molecular Target in Localized and Metastatic Prostate Cancer," appears in the January 2010 issue of the American Journal of Pathology. Prostate cancer cells are often resistant to cell death. Researchers led by Dr. Dario C. Altieri of the University of Massachusetts Medical School, therefore, explored the role of TRAP-1, a protein thought to regulate cell death, in prostate cancer survival. TRAP-1 was highly expressed in both high-grade human prostate cancer lesions and mouse models of prostate cancer, but not in benign or normal prostate tissue. In addition, TRAP-1 overexpression in non-cancer prostate cells inhibited cell death, whereas TRAP-1-deficient prostate cancer cells had enhanced levels of cell death. Moreover, treatment with Gamitrinib, which inhibits TRAP-1, resulted in prostate cancer cell death, but not death of non-cancerous prostate cells. Therefore, targeting TRAP-1 via Gamitrinib treatment may be a viable therapeutic strategy for patients with advanced prostate cancer."

The inflammatory Th 17 subset in immunity against self and non-self antigens. Jin D, Zhang L, Zheng J, Zhao Y. Autoimmunity. 2008 Mar;41(2):154-62. Review. PMID: 18324485 DOI: 10.1080/08916930701776605

It was concluded that omega-3 fatty acid could inhibit the proliferation of pancreatic cancer cell line SW1990 cells and promote their apoptosis. The down-regulation of the cyclin E expression by omega-3 fatty acid might be one of the mechanisms for its anti-tumor effect on pancreatic cancer. Modulatory effects of EPA and DHA on proliferation and apoptosis of pancreatic cancer cells. Zhang W, Long Y, Zhang J, Wang C. J Huazhong Univ Sci Technolog Med Sci. 2007 Oct;27(5):547-50. PMID: 18060632

What if we didn't try to cure cancer, but simply kept tumors from growing too big? That's what radiologist Robert Gatenby of the Moffitt Cancer Center proposes this week in the journal Nature. Gatenby argues that high doses of powerful chemotherapies wreak havoc on a patient's immune system and foster the rapid regrowth of chemoresistant cancers that doctors have no hope of fighting.  So instead of curing cancer, he suggests doctors aim to stabilize the tumor at a tolerable size. In practice, this would mean that doctors identify a target size for an individual tumor that gives the patient the best quality of life.  Then, they will regularly monitor the tumor's growth with medical imaging equipment like a PET/CT scanner (see photo), and regulate doses of anticancer drugs to maintain it at a precise volume.

Berberine suppresses in vitro migration and invasion of human SCC-4 tongue squamous cancer cells through the inhibitions of FAK, IKK, NF-kappaB, u-PA and MMP-2 and -9. Ho YT, Yang JS, Li TC, Lin JJ, Lin JG, Lai KC, Ma CY, Wood WG, Chung JG. Cancer Lett. 2009 Jul 8;279(2):155-62. Epub 2009 Feb 28. PMID: 19251361 doi:10.1016/j.canlet.2009.01.033 There is increasing evidence that urokinase-type plasminogen activator (u-PA) and matrix metalloproteinases (MMPs) play an important role in cancer metastasis and angiogenesis. Inhibition of u-PA and MMPs could suppress migration and invasion of cancer cells. Berberine, one of the main constituents of the plant Rhizoma coptidis, is a type of isoquinoline alkaloid, reported to have anti-cancer effects in different human cancer cell lines. There is however, no available information on effects of berberine on migration and invasion of human tongue cancer cells. Here, we report that berberine inhibited migration and invasion of human SCC-4 tongue squamous carcinoma cells. This action was mediated by the p-JNK, p-ERK, p-p38, IκK and NF-κB signaling pathways resulting in inhibition of MMP-2 and -9 in human SCC-4 tongue squamous carcinoma cells. Our Western blowing analysis also showed that berberine inhibited the levels of urokinase-plasminogen activator (u-PA). These results suggest that berberine down-regulates u-PA, MMP-2 and -9 expressions in SCC-4 cells through the FAK, IKK and NF-κB mediated pathways and a novel function of berberine is to inhibit the invasive capacity of malignant cells.

"Berberine is a quaternary ammonium salt from the group of isoquinoline alkaloids. It is found in such plants as Berberis, goldenseal (Hydrastis canadensis), and Coptis chinensis, usually in the roots, rhizomes, stems, and bark. Berberine is strongly yellow colored, which is why in earlier times berberis species were used to dye wool, leather and wood. Wool is still today dyed with berberine in Northern India Berberine (BBR) is a natural compound with up-regulating activity on both low-density-lipoprotein receptor (LDLR) and insulin receptor (InsR). This one-drug-multiple-target characteristic might be suitable for the treatment of metabolic syndrome.[12] Berberine has been tested and used successfully in experimental[13] and human diabetes mellitus.[14][15][16] Berberine has been shown to lower elevated blood glucose as effectively as metformin.[17] The mechanisms include inhibition of aldose reductase,[18] inducing glycolysis,[19] preventing insulin resistance[20] through increasing insulin receptor expression[14] and acting like incretins. Berberine has drawn extensive attention towards its antineoplastic effects.[43][44] It seems to suppress the growth of a wide variety of tumor cells including breast cancer,[45] leukemia, melanoma,[46] epidermoid carcinoma, hepatoma, oral carcinoma, tongue carcinoma,[47] glioblastoma, prostate carcinoma, gastric carcinoma.[48][49] Animal studies have shown that berberine can suppress chemical-induced carcinogenesis, tumor promotion, tumor invasion,[50][51][52][53][54] prostate cancer,[55][56][57][58] neuroblastoma,[59][60] and leukemia.[34][61] It is a radiosensitzer of tumor cells but not of normal cells

CD40L - a multipotent molecule for tumor therapy. Loskog A, Tötterman TH. Endocr Metab Immune Disord Drug Targets. 2007 Mar;7(1):23-8. Review. PMID: 17346201

Preoperative treatment with a non-steroidal anti-inflammatory drug (NSAID) increases tumor tissue infiltration of seemingly activated immune cells in colorectal cancer. Lönnroth C, Andersson M, Arvidsson A, Nordgren S, Brevinge H, Lagerstedt K, Lundholm K. Cancer Immun. 2008 Feb 29;8:5. PMID: 18307280 MHC II protein (HLA-DP, -DQ, -DR) levels and infiltration by CD4+ T-helper cells of tumor stroma increased upon NSAID treatment, while CD8+ cytotoxic T-lymphocytes increased in both tumor stroma and epithelium. Molecules associated with immunosuppressive T regulatory cells (FOXP3, IL-10) were significantly decreased in indomethacin-exposed tumors. Standard oral administration of NSAID three days preoperatively was enough to increase tumor infiltration by seemingly activated immune cells. These findings agree with previous information that high pr

Multiple roles for CD4+ T cells in anti-tumor immune responses. Kennedy R, Celis E. Immunol Rev. 2008 Apr;222:129-44. Review. PMID: 18363998 DOI: 10.1111/j.1600-065X.2008.00616.x

Interleukin 2-mediated conversion of ovarian cancer-associated CD4+ regulatory T cells into proinflammatory interleukin 17-producing helper T cells. Leveque L, Deknuydt F, Bioley G, Old LJ, Matsuzaki J, Odunsi K, Ayyoub M, Valmori D. J Immunother. 2009 Feb-Mar;32(2):101-8. PMID: 19238008 doi: 10.1097/CJI.0b013e318195b59e Thus, although the impact of TH17 cells on the evolution of EOC remains to be established, our data suggest that local IL-2 treatment in ovarian cancer may result in the conversion of tumor-associated Treg into TH17 cells, relieve Treg-mediated suppression, and contribute to enhance antitumor immunity.

Docosahexaenoic acid suppresses arachidonic acid-induced proliferation of LS-174T human colon carcinoma cells. Habbel P, Weylandt KH, Lichopoj K, Nowak J, Purschke M, Wang JD, He CW, Baumgart DC, Kang JX. World J Gastroenterol. 2009 Mar 7;15(9):1079-84. PMID: 19266600