Skip to main content

Home/ Cancer/ Group items tagged down-regulation

Rss Feed Group items tagged

Matti Narkia

Induction of Ovarian Cancer Cell Apoptosis by 1,25-Dihydroxyvitamin D3 through the Down... - 0 views

  •  
    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
Matti Narkia

Cannabinoids inhibit glioma cell invasion by down-regulating matrix metalloproteinase-2... - 0 views

  •  
    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
Matti Narkia

Modulatory effects of EPA and DHA on proliferation and apoptosis of pancreatic cancer c... - 0 views

  •  
    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
Matti Narkia

Berberine suppresses in vitro migration and invasion of human SCC-4 tongue sq... - 0 views

  •  
    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.
Matti Narkia

Docosahexaenoic acid suppresses arachidonic acid-induced proliferation of LS-174T human... - 0 views

  •  
    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
1 - 5 of 5
Showing 20 items per page