ABSTRACT
<p><b>OBJECTIVE</b>To study the effects of c9,t11-conjugated linoleic acid on the killing ability of macrophage to B16-MB cells in C57 mice and explore its possible mechanism.</p><p><b>METHODS</b>The five levels of CLA was designed as 0, 25, 50, 75, 100 micro mol/L. After macrophage was treated with CLA for 24 h, the killing ability of macrophage on B16-MB cells was evaluated by MTT, The expression of C57 mice macrophage cytokine IL-6, TNF-alpha and iNOS mRNA was detected by RT-PCR. The expression of Erk protein was examined by Western Blot assay.</p><p><b>RESULTS</b>The inhibitory effect of macrophage on tumor cell depend on the treatment of the increased c9,t11-CLA level, at the same time, the expression of IL-6, TNF-alpha and iNOS mRNA increased, the expression of Erk decreased with the elevating dose of CLA.</p><p><b>CONCLUSIONS</b>c9,t11-CLA could increase the killing ability of macrophage in mice to B16-MB cells, and it was associated with induction of IL-6, TNF-alpha and iNOS mRNA expression. We speculate that antitumor ability of CLA may be associated with taking part in body immune regulation action, and the effects of CLA on the killing ability of murine macrophage to B16-MB cells was not associated with the MAPKErk pathway.</p>
Subject(s)
Animals , Mice , Blotting, Western , Cell Division , Cell Line, Tumor , Coculture Techniques , Dose-Response Relationship, Drug , Interleukin-6 , Genetics , Linoleic Acids, Conjugated , Pharmacology , Macrophages , Physiology , Melanoma, Experimental , Pathology , Mice, Inbred C57BL , Mitogen-Activated Protein Kinases , Metabolism , Nitric Oxide Synthase , Genetics , RNA, Messenger , Genetics , Metabolism , Reverse Transcriptase Polymerase Chain Reaction , Tumor Necrosis Factor-alpha , GeneticsABSTRACT
<p><b>OBJECTIVES</b>To study the effects of c9,t11-conjugated linoleic acid (c9,t11-CLA) on invasive ability of human gastric carcinoma cell line (SGC-7901) and to explore its possible mechanism.</p><p><b>METHODS</b>Reconstituted basement membrane invasion assay was used to evaluate invasive ability of cancer cells. Expression of TIMP-1, TIMP-2 and nm23-H(1) mRNA was measured by reverse transcription polymerase chain reaction (RT-PCR) in SGC-7901 cells.</p><p><b>RESULTS</b>At the concentrations of 200 micromol/L, 100 micromol/L and 50 micromol/L, c9,t11-CLA suppressed their reconstituted basement membrane invasion of SGC-7901 by 53.7%, 40.9% and 29.3%, respectively. c9,t11-CLA could induce the expression of TIMP-1, TIMP-2 and nm23-H(1) mRNA in SGC-7901 cells.</p><p><b>CONCLUSIONS</b>The invasion of SGC-7901 cells could be inhibited by c9,t11-CLA through reconstituted basement membrane. Anti-invasion action of c9,t11-CLA might be associated with induction of expression of TIMP-1, TIMP-2 and nm23-H(1) mRNA in tumor cells.</p>
Subject(s)
Humans , Adenocarcinoma , Pathology , Gene Expression , Linoleic Acid , Pharmacology , Therapeutic Uses , Monomeric GTP-Binding Proteins , Genetics , NM23 Nucleoside Diphosphate Kinases , Neoplasm Invasiveness , Nucleoside-Diphosphate Kinase , RNA, Messenger , Stomach Neoplasms , Pathology , Tissue Inhibitor of Metalloproteinase-1 , Genetics , Tissue Inhibitor of Metalloproteinase-2 , Genetics , Transcription Factors , Genetics , Tumor Cells, CulturedABSTRACT
<p><b>OBJECTIVES</b>To determine the effect of cis-9, trans-11-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and its possible mechanism of inhibition cancer growth.</p><p><b>METHODS</b>Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B(1), D(1), p16(ink4a) and p21(cip/wafl) of MCF-7 cells which were treated with various c9, t11-CLA concentrations (25 mM, 50 mM, 100 mM and 200 mM) of c9, t11-CLA for 24 and 48 h, with negative controls (0.1% ethanol).</p><p><b>RESULTS</b>The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9, t11-CLA. MCF-7 cells, after treatment with various c9, t11-CLA doses mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively and the inhibitory effect of c9, t11-CLA on DNA synthesis (except for 25 mM, 24 h) incorporated significantly less(3)H-TdR than did the negative control (P<0.05 andP<0.01). To further investigate the influence on the cell cycle progression, we found that c9, t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that MCF-7 cells preincubated in media supplemented with different c9, t11-CLA concentrations at various times significantly decreased the expressions of PCNA, and Cyclin, A, B(1), D(1) compared with the negative controls (P<0.01), whereas the expressions of p16(ink4a) and p21(cip/wafl), cyclin-dependent kinases inhibitors (CDKI), were increased.</p><p><b>CONCLUSIONS</b>The cell growth and proliferation of MCF-7 cells is inhibited by c9, t11-CLA by blocking the cell cycle, which reduces expressions of cyclin A, B(1), D(1) and enhances expressions of CDKI (p16(ink4a) and p21(cip/wafl)).</p>