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Objective To investigate the expressions of histone lysine-specific demethylase 1 (LSD1),O6-methylguanine DNA methyltransferase (MGMT) and cell proliferation-associated antigen Ki-67 in high-grade glioma and their influences on prognosis.Methods Sixty-five cases of grade Ⅲ and Ⅳ glioma confirmed by pathology from January 2011 to June 2017 in the First Affiliated Hospital of Xinjiang Medical University were selected.Immunohistochemistry (SP method) was used to detect the expressions of LSD1,MGMT and Ki-67 in pathological specimens.The therapeutic effect was evaluated by long-term follow-up.The relationships between the three markers and pathological grade,progression-free survival (PFS) and overall survival (OS) were analyzed.Results The overall positive rates of LSD1,MGMT and Ki-67 in the 65 high-grade glioma specimens were 70.8％ (46/65),60.0％ (39/65) and 100.0％ (65/65),respectively.There were no significant differences in the expressions of LSD1 and MGMT in grade Ⅲ and Ⅳ glioma (x2 =1.588,P =0.208,x2 =0.013,P=0.908).Ki-67 expression (+),(++),(+++) in grade Ⅳ glioma were observed in 18,19 and 11 cases,respectively.Ki-67 expression (+),(++) in grade Ⅲ glioma were observed in 11,5 cases,and 1 case was (+++),and the difference in expression intensity between the two groups was statistically significant (Z =-2.083,P =0.037).Log-rank test showed that the positive expressions of LSD1,MGMT and Ki-67 were negatively correlated with the PFS of patients with high-grade glioma (x2 =12.217,P =0.007;x2=4.446,P =0.035;x2=12.536,P =0.002),also were negatively correlated with OS (x2 =11.708,P =O.008;x2 =6.637,P =0.010;x2 =11.807,P =0.003).Grade Ⅳ patients were more likely to have relapse progression than grade Ⅲ patients (x2 =6.573,P =0.010),and OS was shorter (x2 =3.974,P=0.046).Cox proportional hazards model analysis showed that the expressions of LSD1 (HR =1.361,95％CI:1.094-1.694,P=0.006;HR=1.406,95％CI:1.117-1.771,P =0.004) and Ki-67 (HR=1.703,95％ CI:1.175-2.468,P =0.005;HR =1.778,95％ CI:1.209-2.616,P =0.003) were the independent prognostic risk factors for PFS and OS of patients with high-grade glioma.Correlation analysis results showed that the expression of MGMT was positively correlated with the expression of LSD1 (r =0.406,P =0.001).Conclusion LSD1,MGMT and Ki-67 have higher positive expression rates in high-grade glioma.MGMT is a prognostic factor for high-grade glioma,and LSD1 and Ki-67 can be used as independent predictors of prognosis for high-grade gliomas.
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Objective@#To investigate the expressions of histone lysine-specific demethylase 1 (LSD1), O6-methylguanine DNA methyltransferase (MGMT) and cell proliferation-associated antigen Ki-67 in high-grade glioma and their influences on prognosis.@*Methods@#Sixty-five cases of grade Ⅲ and Ⅳ glioma confirmed by pathology from January 2011 to June 2017 in the First Affiliated Hospital of Xinjiang Medical University were selected. Immunohistochemistry (SP method) was used to detect the expressions of LSD1, MGMT and Ki-67 in pathological specimens. The therapeutic effect was evaluated by long-term follow-up. The relationships between the three markers and pathological grade, progression-free survival (PFS) and overall survival (OS) were analyzed.@*Results@#The overall positive rates of LSD1, MGMT and Ki-67 in the 65 high-grade glioma specimens were 70.8% (46/65), 60.0% (39/65) and 100.0% (65/65), respectively. There were no significant differences in the expressions of LSD1 and MGMT in grade Ⅲ and Ⅳ glioma (χ2=1.588, P=0.208, χ2=0.013, P=0.908). Ki-67 expression (+ ), (+ + ), (+ + + ) in grade Ⅳ glioma were observed in 18, 19 and 11 cases, respectively. Ki-67 expression (+ ), (+ + ) in grade Ⅲ glioma were observed in 11, 5 cases, and 1 case was (+ + + ), and the difference in expression intensity between the two groups was statistically significant (Z=-2.083, P=0.037). Log-rank test showed that the positive expressions of LSD1, MGMT and Ki-67 were negatively correlated with the PFS of patients with high-grade glioma (χ2=12.217, P=0.007; χ2=4.446, P=0.035; χ2=12.536, P=0.002), also were negatively correlated with OS (χ2=11.708, P=0.008; χ2=6.637, P=0.010; χ2=11.807, P=0.003). Grade Ⅳ patients were more likely to have relapse progression than grade Ⅲ patients (χ2=6.573, P=0.010), and OS was shorter (χ2=3.974, P=0.046). Cox proportional hazards model analysis showed that the expressions of LSD1 (HR=1.361, 95%CI: 1.094-1.694, P=0.006; HR=1.406, 95%CI: 1.117-1.771, P=0.004) and Ki-67 (HR=1.703, 95%CI: 1.175-2.468, P=0.005; HR=1.778, 95%CI: 1.209-2.616, P=0.003) were the independent prognostic risk factors for PFS and OS of patients with high-grade glioma. Correlation analysis results showed that the expression of MGMT was positively correlated with the expression of LSD1 (r=0.406, P=0.001).@*Conclusion@#LSD1, MGMT and Ki-67 have higher positive expression rates in high-grade glioma. MGMT is a prognostic factor for high-grade glioma, and LSD1 and Ki-67 can be used as independent predictors of prognosis for high-grade gliomas.
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Objective Lysine-specific demethylase 1 (LSD1) is a flavin adenine dinucleotide-dependent oxidase, which participates in many biological processes , such as cell proliferation and differentiation and gene activation and repression .The aim of this study was to investigate LSD1 acetylation by histone deacetylase inhib -itor trichostatin A ( TSA) and its effect on TSA-induced apoptosis of ovarian cancer cells . Methods LSD1 shRNA was synthesized and implanted into the pLKO-Tet-On lentiviral vector , which was transfected into HO8910 and SKOV3 ovarian cancer cell lines , and then the transfected cells were screened with 1.5μg/mL puromycin for one week until stable clones were established .The cells were treated for 48 hours with methanol (2 mg/mL, control), TSA (200 nmol/L), TCP (100μmol/L), or TSA+TCP.And in the experiment of RNA interfering the LSD1 expression, the cells were also treated for 48 hours with methanol (2 mg/mL, control), TSA (200 nmol/L), Dox (100 ng/mL), or TSA +Dox.The levels of LSD1 acetylation and its substrate histone H3 lysine 4 dimethylation (H3K4me2) were de-tected by immunoprecipitation (IP) and Western blot.The apoptosis of the cells was determined by Annexin Ⅴ/PI staining and flow cytometry, the transcription levels of the Bax and p21 genes detected by real-time quantitative PCR, and the H3K4me2levels in the promoter regions of Bax and p21 measured by chromatin immunoprecipitation ( ChIP ) .Results In comparison with the methanol control, the TSA group showed significantly increased levels of LSD 1 acetylation in the HO8910(1.00±0.29 vs 5.83±0.46, P<0.01) and SKOV3 cells ( 1.00±0.24 vs 5.07±0.35, P<0.01) as well as that of H3K4me2 ( P<0.01);the total apoptosis rates of HO 8910 and SKOV3 cells were remarkably increased in the TSA, TCP, and TSA+TCP groups (P<0.05), even more significantly in the TSA+TCP than in the TSA and TCP groups ( P<0.05) .The mRNA expressions of Bax and p21 in the HO8910 cells were markedly upregulated in the TSA, Dox, and TSA+Dox groups (P<0.05), even more significantly in the latter than in the former two groups (P<0.05).The TSA group exhibited a higher level of H 3K4me2 than the methanol control in the promoters of Bax(2 .92±0.26 vs 0.68±0.19, P<0.01) and p21 (3.07±0.29 vs 0.93±0.17, P<0.01). Conclusion TSA induces the LSD1 acetylation, while suppression of LSD1 expres-sion and activity may enhance the antitumor activity of TSA .
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Objective Lysine-specific demethylase 1 (LSD1) is a flavin adenine dinucleotide-dependent oxidase, which participates in many biological processes , such as cell proliferation and differentiation and gene activation and repression .The aim of this study was to investigate LSD1 acetylation by histone deacetylase inhib -itor trichostatin A ( TSA) and its effect on TSA-induced apoptosis of ovarian cancer cells . Methods LSD1 shRNA was synthesized and implanted into the pLKO-Tet-On lentiviral vector , which was transfected into HO8910 and SKOV3 ovarian cancer cell lines , and then the transfected cells were screened with 1.5μg/mL puromycin for one week until stable clones were established .The cells were treated for 48 hours with methanol (2 mg/mL, control), TSA (200 nmol/L), TCP (100μmol/L), or TSA+TCP.And in the experiment of RNA interfering the LSD1 expression, the cells were also treated for 48 hours with methanol (2 mg/mL, control), TSA (200 nmol/L), Dox (100 ng/mL), or TSA +Dox.The levels of LSD1 acetylation and its substrate histone H3 lysine 4 dimethylation (H3K4me2) were de-tected by immunoprecipitation (IP) and Western blot.The apoptosis of the cells was determined by Annexin Ⅴ/PI staining and flow cytometry, the transcription levels of the Bax and p21 genes detected by real-time quantitative PCR, and the H3K4me2levels in the promoter regions of Bax and p21 measured by chromatin immunoprecipitation ( ChIP ) .Results In comparison with the methanol control, the TSA group showed significantly increased levels of LSD 1 acetylation in the HO8910(1.00±0.29 vs 5.83±0.46, P<0.01) and SKOV3 cells ( 1.00±0.24 vs 5.07±0.35, P<0.01) as well as that of H3K4me2 ( P<0.01);the total apoptosis rates of HO 8910 and SKOV3 cells were remarkably increased in the TSA, TCP, and TSA+TCP groups (P<0.05), even more significantly in the TSA+TCP than in the TSA and TCP groups ( P<0.05) .The mRNA expressions of Bax and p21 in the HO8910 cells were markedly upregulated in the TSA, Dox, and TSA+Dox groups (P<0.05), even more significantly in the latter than in the former two groups (P<0.05).The TSA group exhibited a higher level of H 3K4me2 than the methanol control in the promoters of Bax(2 .92±0.26 vs 0.68±0.19, P<0.01) and p21 (3.07±0.29 vs 0.93±0.17, P<0.01). Conclusion TSA induces the LSD1 acetylation, while suppression of LSD1 expres-sion and activity may enhance the antitumor activity of TSA .
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Objective To investigate the effects of shRNA interference (RNAi) targeting the histone lysine specific demethylase 1 (LSD1) on the proliferation and apoptosis in acute leukemia (AL) cells. Methods LSD1 shRNA vectors were constructed and transduced into HL-60 and SHI-1 AL cell lines. Inhibitory efficiency of LSD1 was detected by real-time quantitative PCR (RT-qPCR) and Western blot respectively. Cell proliferation was assessed by methyl thiazolyl tetrazolium (MTT), and cell apoptosis was measured by flow cytometry. Results After interference of LSD1, the expression levels of LSD1 mRNA and protein in HL-60 and SHI-1 cells (mRNA: 0.242 ±0.023, 0.207 ±0.006; Protein: 0.256 ±0.015, 0.486 ±0.042) were decreased compared with blank control group without transfection process (mRNA: 1.021 ±0.178, 1.039 ±0.395; Protein:0.552 ±0.026, 0.754 ±0.060) and empty vector negative control group (shNC group) (mRNA: 0.935 ±0.136, 1.016±0.203;Protein: 0.500±0.026, 0.750±0.049) (P<0.05). The levels of their cell proliferation (absorbance value: 0.712±0.010, 0.549±0.007) were inhibited compared with blank control group (absorbance value:0.823±0.010, 0.625±0.005) and shNC group(absorbance value: 0.818±0.019, 0.621±0.003) (P< 0.05). While cell apoptosis rates were increased [(32.80 ±1.35) %, (23.49 ±1.40) %] compared with blank control group [(8.08 ±0.62) %, (7.28 ±1.17) %] and shNC group [(8.08 ±0.62) %, (7.28 ±1.17) %] (P< 0.05). Conclusions Lentivirus-mediated shRNA interferencing LSD1 can inhibit cells ' proliferation and promote apoptosis of HL-60 and SHI-1 AL cell lines, indicating that LSD1 may be a potential biological molecular marker and a new treatment target for AL.
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Objective To investigate the expressions and relationship between lysine-specific demethylase 1 (LSD1) and E-cadherin protein in gastric cancer tissues and adjacent normal tissues,and the correlation with the clinicopathological features and prognosis of patients with gastric cancer.Methods The case-control study was adopted.The gastric cancer tissues and adjacent normal tissues were collected by surgical resection from 80 patients with gastric cancer who were admitted to the Xiangya Hospital of Central South University from June 2008 to June 2009.Expressions of LSD1 and E-cadherin protein were detected by immunohistochemistry (IHC).The follow-up of telephone interview was performed to detect survival of patients till June 2015.Relationships between the expressions of LSD1 and E-cadherin protein and clinicopathological features or prognosis of patients were analyzed.Comparison of count data and correlation were analyzed by the chi-square test and Spearman rank correlation analysis.Survival curve was drawn using the Kaplan-Meier method,and survival analysis was done using the Log-rank test.Results Expressions of LSD1 in cancer tissues and adjacent normal tissues were located at the cell nucleus.The positive expression rate of LSD1 was 67.5％ (54/80) and 43.8％ (35/80) in cancer tissues and adjacent normal tissues,respectively,with a significant difference (x2=9.141,P ＜ 0.05).Expressions of E-cadherin protein in cancer tissues and adjacent normal tissues were located at the cell membrane and cytoplasm.The positive expression rate of E-cadherin was 63.8％ (51/80) and 81.3％ (65/80) in cancer tissues and adjacent normal tissues,respectively,with a significant difference (x2 =6.140,P ＜ 0.05).The positive expression rate of LSD1 was 83.3％ (25/30),76.0％ (19/25) and 40.0％ (10/25) in the low-,moderate-and high-differentiated tumors,37.5％ (6/16),72.7％ (16/22),71.9％ (23/32) and 90.0％ (9/10) in the Ⅰ,Ⅱ,Ⅲ and Ⅳ stages of TNM stage,36.4％ (4/11) and 72.5 ％ (50/69) in patients without and with lymph node metastasis,respectively,showing significant differences (x2=12.870,9.425,4.111,P ＜ 0.05).The positive expression rate of E-cadherin protein was 53.3％ (16/30),56.0％ (14/25) and 84.0％ (21/25) in the low-,moderate-and high-differentiated tumors,75.0％ (12/16),63.6％ (14/22),71.9％ (23/32) and 20.0％ (2/10) in the Ⅰ,Ⅱ,Ⅲ and Ⅳ stages of TNM stage,100.0％ (11/11) and 58.0％ (40/69) in patients without and with lymph node metastasis,70.0％ (49/70) and 20.0％ (2/10) in patients without and with distant metastasis,respectively,showing significant differences (/x2 =6.494,10.073,5.547,7.426,P ＜ 0.05).There was a negative correlation in expressions between LSD1 and E-cadherin protein (r =-0.355,P ＜ 0.05).The survival time and 5-year overall survival rate of patients with positive and negative expressions of LSD1 were (36.9 ± 2.5) months and 31.1％,(47.4 ± 3.4) months and 56.0％,respectively,showing a significant difference (x2=4.550,P ＜0.05).The survival time and 5-year overall survival rate of the patients with positive and negative expressions of E-cadherin protein were (44.0 ± 2.5) months and 46.7％,(32.6 ± 3.5) months and 24.9％,respectively,showing a significant difference (x2 =7.306,P ＜ 0.05).Conclusions Positive expression of LSD1 in gastric cancer tissues is higher than that in adjacent normal tissues.There are increased expression of LSD1 and reduced expression of E-cadherin protein in low-differentiated gastric cancer tissues and high TNM stage,showing a negative correlation between them.Positive expression of LSD1 and negative expression of E-cadherin protein may indicate a poor prognosis.