1.Expression of Caspase-3 and P-gp in hepatocellular carcinoma and their relationship
Lei JIN ; Feng ZHU ; Xihu QIN ; Yan TAN ; Tianping LUO
Journal of International Oncology 2010;37(9):715-718
Objective To measure the expression of Caspase-3 and P-gp in hepatocellular carcinoma (HCC) and adjacent tissues, and to examine these two proteins' relationships with HCC clinical and pathological characteristics and the associations between the two proteins. Methods The expression of Caspase-3 and P-gp were measured in 50 HCC tissues and adjacent tissues by EnvisionTM immunohistochemistry. HCC clinic and pathological characteristics and follow-up data were also collected and analyzed. Results The expression of Caspase-3 in HCC tissues was significantly lower than that in adjacent tissues(P <0.05). The expression of Caspase-3 in HCC tissues was significantly associated with HCC's Edmonson grade and the presence of hepatitis envelope(P <0.05). On the other hand, the expression of P-gp in HCC tissues was significantly higher than that in adjacent tissues( P <0.05 ). P-gp expression in HCC tissues was significantly correlated with HCC's Edmonson grade and the presence of cirrhosis(P < 0.05 ). The expression of Caspase-3 and P-gp was negatively correlated ( r = - 0. 600,P = 0.000). A better prognosis was observed among HCC patients with either positive Caspase-3 expression or negative P-gp expression(P < 0.05). Conclusion Caspase-3 may promote apoptosis and inhibit the development of HCC, while P-gp may have an anti-apoptosis function and play a role in HCC's drug resistance. P-gp can inhibit the function of Caspase-3 and an absence or low expression of Caspase-3 may be related to apoptosis resistance and multidrug resistance.
2.The lipid-associated membrane proteins derived from Mycoplasma pneumoniae strains induced the expression of HO-1 in THP-1 cells
Tianping TAN ; Guangli OU ; Yan LIU ; Jun HE ; Xiaoxing YOU ; Yanhua ZENG ; Minjun YU ; Cuiming ZHU
Chinese Journal of Microbiology and Immunology 2015;(2):112-116
Objective To investigate the effects of lipid-associated membrane proteins ( LAMPs) derived from Mycoplasma pneumoniae ( M.pneumoniae) strains on the expression of heme oxygenase 1 ( HO-1) in a human monocyte cell line (THP-1).Methods THP-1 cells were in vitro cultured with different concentrations of LAMPs for different times.The cytotoxicity of LAMPs to THP-1 cells was analyzed by using lactate dehydrogenase ( LDH) releasing test.The expression of HO-1 at protein and mRNA levels were de-tected by Western blot and real-time RT-PCR, respectively.The enzymatic activity of HO-1 protein was ex-amined by colorimetric assay.THP-1 cells stimulated with PBS and LPS were set up as the negative and pos-itive controls, respectively.Results A significantly enhanced LDH releasing rate was observed in THP-1 cells treated with 10 μg/ml of LAMPs.The expression of HO-1 at protein and mRNA levels in THP-1 cells were induced by LAMPs in a dose-dependent and time-dependent manner.The highest level of HO-1 protein was detected in THP-1 cells treated with 5.0 μg/ml of LAMPs.The transcriptional levels of HO-1 induced by LAMPs were significantly elevated at 3 h, peaked at 9 h and were decreased at 12 h.The expression of HO-1 protein in THP-1 cells was enhanced after 8 h of treatment with LAMPs and a significant decrease was observed at 20 h after reaching peaks at 12 h and 16 h.The activity of HO-1 protein was significantly en-hanced along with the increased expression of HO-1 protein.Conclusion The LAMPs derived from M.pneumoniae strains induced the expression of HO-1 at mRNA and protein levels.Moreover, the enzyme activity of HO-1 protein was enhanced in LAMPs treated THP-1 cells.
3.Quinine oxidoreductase 1 inhibits the secretion of IL-8 in Mycoplasma pneumoniae lipid-associated membrane proteins stimulated the THP-1 monocyte line
Weiyan DING ; Tianping TAN ; Nan DING ; Tingting LI ; Lijun HUANG ; Shuihong LI ; Cuiming ZHU
Chinese Journal of Microbiology and Immunology 2021;41(6):460-465
Objective:To investigate the effects and regulation mechanism of lipid-associated membrane proteins (LAMPs) derived from Mycoplasma pneumoniae( Mp) on the expression of quinine oxidoreductase 1 (NQO-1) in human monocyte cell line THP-1 cells, and to know the effect of NQO-1 to interleukin 8 secretion in LAMPs stimulated cells, so as to better understand the regulation mechanism upon Mp infection. Methods:Mp were cultivated and the precipitate was collected to extract LAMPs. The cytotoxicity of LAMPs to THP-1 cells was analyzed by using CCK8 test. THP-1 cells were cultured in vitro with different concentrations of LAMPs for different times, and the expression of NQO-1 protein was detected by Western blot. Nrf2 siRNA was used to investigate the role of Nrf2 in NQO-1 expression in LAMPs induced cells, and NQO-1 inhibitor Diminutol was performed to test whether they blocked interleukin 8 (IL-8) secretion when treated with LAMPs in THP-1 cells. Results:LAMPs extracted from Mp had no cytotoxicity to THP-1 cells. The expression of NQO-1 protein in LAMPs-stimulated THP-1 cells showed a dose-dependent and time-dependent manner. The production of NQO-1 protein reached peaks when treated with 5.0 μg/ml or 7.5 μg/ml of LAMPs for 12 h. Silencing of Nrf2 by siRNA significantly decreased NQO-1 production, and blocking NQO-1 by Dim increased the level of IL-8 in LAMPs-stimulated cells. Conclusions:LAMPs derived from Mp induced the expression of NQO-1 protein in THP-1 cells via Nrf2, and NQO-1 can inhibit IL-8 secretion in LAMPs stimulated monocytes.