1.To compare the efficacy and incidence of severe hematological adverse events of flumatinib and imatinib in patients newly diagnosed with chronic phase chronic myeloid leukemia.
Xiao Shuai ZHANG ; Bing Cheng LIU ; Xin DU ; Yan Li ZHANG ; Na XU ; Xiao Li LIU ; Wei Ming LI ; Hai LIN ; Rong LIANG ; Chun Yan CHEN ; Jian HUANG ; Yun Fan YANG ; Huan Ling ZHU ; Ling PAN ; Xiao Dong WANG ; Gui Hui LI ; Zhuo Gang LIU ; Yan Qing ZHANG ; Zhen Fang LIU ; Jian Da HU ; Chun Shui LIU ; Fei LI ; Wei YANG ; Li MENG ; Yan Qiu HAN ; Li E LIN ; Zhen Yu ZHAO ; Chuan Qing TU ; Cai Feng ZHENG ; Yan Liang BAI ; Ze Ping ZHOU ; Su Ning CHEN ; Hui Ying QIU ; Li Jie YANG ; Xiu Li SUN ; Hui SUN ; Li ZHOU ; Ze Lin LIU ; Dan Yu WANG ; Jian Xin GUO ; Li Ping PANG ; Qing Shu ZENG ; Xiao Hui SUO ; Wei Hua ZHANG ; Yuan Jun ZHENG ; Qian JIANG
Chinese Journal of Hematology 2023;44(9):728-736
Objective: To analyze and compare therapy responses, outcomes, and incidence of severe hematologic adverse events of flumatinib and imatinib in patients newly diagnosed with chronic phase chronic myeloid leukemia (CML) . Methods: Data of patients with chronic phase CML diagnosed between January 2006 and November 2022 from 76 centers, aged ≥18 years, and received initial flumatinib or imatinib therapy within 6 months after diagnosis in China were retrospectively interrogated. Propensity score matching (PSM) analysis was performed to reduce the bias of the initial TKI selection, and the therapy responses and outcomes of patients receiving initial flumatinib or imatinib therapy were compared. Results: A total of 4 833 adult patients with CML receiving initial imatinib (n=4 380) or flumatinib (n=453) therapy were included in the study. In the imatinib cohort, the median follow-up time was 54 [interquartile range (IQR), 31-85] months, and the 7-year cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) were 95.2%, 88.4%, 78.3%, and 63.0%, respectively. The 7-year FFS, PFS, and OS rates were 71.8%, 93.0%, and 96.9%, respectively. With the median follow-up of 18 (IQR, 13-25) months in the flumatinib cohort, the 2-year cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) were 95.4%, 86.5%, 58.4%, and 46.6%, respectively. The 2-year FFS, PFS, and OS rates were 80.1%, 95.0%, and 99.5%, respectively. The PSM analysis indicated that patients receiving initial flumatinib therapy had significantly higher cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) and higher probabilities of FFS than those receiving the initial imatinib therapy (all P<0.001), whereas the PFS (P=0.230) and OS (P=0.268) were comparable between the two cohorts. The incidence of severe hematologic adverse events (grade≥Ⅲ) was comparable in the two cohorts. Conclusion: Patients receiving initial flumatinib therapy had higher cumulative incidences of therapy responses and higher probability of FFS than those receiving initial imatinib therapy, whereas the incidence of severe hematologic adverse events was comparable between the two cohorts.
Adult
;
Humans
;
Adolescent
;
Imatinib Mesylate/adverse effects*
;
Incidence
;
Antineoplastic Agents/adverse effects*
;
Retrospective Studies
;
Pyrimidines/adverse effects*
;
Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy*
;
Treatment Outcome
;
Benzamides/adverse effects*
;
Leukemia, Myeloid, Chronic-Phase/drug therapy*
;
Aminopyridines/therapeutic use*
;
Protein Kinase Inhibitors/therapeutic use*
2.Impact of KIT D816 mutation on salvage therapy in relapsed acute myeloid leukemia with t(8;21) translocation.
Ben Fa GONG ; Ye Hui TAN ; Ai Jun LIAO ; Jian LI ; Yue Ying MAO ; Ning LU ; Yi DING ; Er Lie JIANG ; Tie Jun GONG ; Zhi Lin JIA ; Yu SUN ; Bing Zong LI ; Shu Chuan LIU ; Juan DU ; Wen Rong HUANG ; Hui WEI ; Jian Xiang WANG
Chinese Journal of Hematology 2018;39(6):460-464
Objective: To evaluate the impact of KIT D816 mutation on the salvage therapy in relapsed acute myeloid leukemia (AML) with t(8;21) translocation. Method: The characteristics of the first relapsed AML with t(8;21) translocation from 10 hospitals were retrospectively collected, complete remission (CR(2)) rate after one course salvage chemotherapy and the relationship between KIT mutation and CR(2) rate was analyzed. Results: 68 cases were enrolled in this study, and 30 cases (44.1%) achieved CR(2). All patients received KIT mutation detection, and KIT D816 mutation was identified in 26 cases. The KIT D816 positive group had significantly lower CR(2) compared with non-KIT D816 group (23.1% vs 57.1%, χ(2)=7.559, P=0.006), and patients with longer CR(1) duration achieved significantly higher CR(2) than those with CR(1) duration less than 12 months (74.1% vs 31.9%, χ(2)=9.192, P=0.002). KIT D816 mutation was tightly related to shorter CR(1) duration. No significant difference of 2 years post relapse survival was observed between KIT D816 mutation and non-KIT D816 mutation group. Conclusion: KIT D816 mutation at diagnosis was an adverse factor on the salvage therapy in relapsed AML with t(8;21) translocation, significantly related to shorter CR1 duration, and can be used for prediction of salvage therapy response. KIT D816 mutation could guide the decision-making of salvage therapy in relapsed AML with t(8;21) translocation.
Antineoplastic Combined Chemotherapy Protocols
;
Cytarabine
;
Humans
;
Leukemia, Myeloid, Acute/therapy*
;
Prognosis
;
Retrospective Studies
;
Salvage Therapy
3.Value of Kidney Disease Improving Global Outcomes Urine Output Criteria in Critically Ill Patients: A Secondary Analysis of a Multicenter Prospective Cohort Study.
Jun-Ping QIN ; Xiang-You YU ; Chuan-Yun QIAN ; Shu-Sheng LI ; Tie-He QIN ; Er-Zhen CHEN ; Jian-Dong LIN ; Yu-Hang AI ; Da-Wei WU ; De-Xin LIU ; Ren-Hua SUN ; Zhen-Jie HU ; Xiang-Yuan CAO ; Fa-Chun ZHOU ; Zhen-Yang HE ; Li-Hua ZHOU ; You-Zhong AN ; Yan KANG ; Xiao-Chun MA ; Ming-Yan ZHAO ; Li JIANG ; Yuan XU ; Bin DU ; null
Chinese Medical Journal 2016;129(17):2050-2057
BACKGROUNDUrine output (UO) is an essential criterion of the Kidney Disease Improving Global Outcomes (KDIGO) definition and classification system for acute kidney injury (AKI), of which the diagnostic value has not been extensively studied. We aimed to determine whether AKI based on KDIGO UO criteria (KDIGOUO) could improve the diagnostic and prognostic accuracy, compared with KDIGO serum creatinine criteria (KDIGOSCr).
METHODSWe conducted a secondary analysis of the database of a previous study conducted by China Critical Care Clinical Trial Group (CCCCTG), which was a 2-month prospective cohort study (July 1, 2009 to August 31, 2009) involving 3063 patients in 22 tertiary Intensive Care Units in Mainland of China. AKI was diagnosed and classified separately based on KDIGOUOand KDIGOSCr. Hospital mortality of patients with more severe AKI classification based on KDIGOUOwas compared with other patients by univariate and multivariate regression analyses.
RESULTSThe prevalence of AKI increased from 52.4% based on KDIGOSCrto 55.4% based on KDIGOSCrcombined with KDIGOUO. KDIGOUOalso resulted in an upgrade of AKI classification in 7.3% of patients, representing those with more severe AKI classification based on KDIGOUO. Compared with non-AKI patients or those with maximum AKI classification by KDIGOSCr, those with maximum AKI classification by KDIGOUOhad a significantly higher hospital mortality of 58.4% (odds ratio [OR]: 7.580, 95% confidence interval [CI]: 4.141-13.873, P< 0.001). In a multivariate logistic regression analysis, AKI based on KDIGOUO (OR: 2.891, 95% CI: 1.964-4.254, P< 0.001), but not based on KDIGOSCr (OR: 1.322, 95% CI: 0.902-1.939, P = 0.152), was an independent risk factor for hospital mortality.
CONCLUSIONUO was a criterion with additional value beyond creatinine criterion for AKI diagnosis and classification, which can help identify a group of patients with high risk of death.
Acute Disease ; mortality ; Aged ; Creatinine ; blood ; Critical Illness ; mortality ; Female ; Hospital Mortality ; Humans ; Kaplan-Meier Estimate ; Kidney Diseases ; blood ; mortality ; pathology ; urine ; Logistic Models ; Male ; Middle Aged ; Prognosis ; Prospective Studies ; Risk Factors
4.Effects of nasal intermittent positive pressure ventilation compared with continuous positive airway pressure for respiratory distress syndrome in low birth weight preterm infants
Jia CHEN ; Weiwei GAO ; Chuan NIE ; Fang XU ; Lanlan DU ; Shu LIANG ; Jie YANG
Chinese Journal of Perinatal Medicine 2015;18(2):111-116
Objective To investigate the effects of early nasal intermittent positive pressure ventilation (NIPPV) compared with early continuous positive airway pressure (NCPAP) in low birth weight preterm infants with respiratory distress syndrome (RDS).Methods We performed a prospective,randomized controlled trial involving 364 low birth weight preterm infants with respiratory distress syndrome within 6 hours of birth.The infants were randomly assigned to NIPPV (n=188) or NCPAP (n=176) groups.Non invasive ventilation was initiated in the neonatal intensive care unit (NICU).The rate of mechanical intubation (within 3 days or 7 days),the use of pulmonary surfactant (PS),the rate of complications and mortality were compared between the two groups.Mann Whitney U,t and Chi-square tests were used for statistical analysis.Results The average time of invasive mechanical ventilation in NIPPV group were lower than that in NCPAP group[2.0 (1.0-4.0) d vs 7.0 (3.0-8.5) d,U=-3.457,P=0.001].The need for intubation and mechanical ventilation by day 3 and day 7 in the NIPPV group were less than those in the NCPAP group [day 3:4.8% (9/188) vs 10.8% (19/176),x2=4.621,P=0.032; day 7:9.0% (17/188) vs 16.5% (29/176),x2=4.551,P=0.033].In the NIPPV group,infants who got PS therapy was less than that in the NCPAP group [3.2% (6/188) vs 8.5% (15/176),x2=4.752,P=0.029].There was no significant difference in the fatality rate between the NIPPV and the NCPAP group [12.8% (24/188) vs 10.8% (19/176),P > 0.05].There were no significant difference in the incidence of air leak,intracranial hemorrhage,periventricular leukomalacia,retinopathy of prematurity,necrotizing enterocolitis,patent ductus arteriosus,and bronchopulmonary dysplasia between the NIPPV group and the NCPAP group.Conclusion Among low birth weight prcterm infants with RDS,the early use of NIPPV reduces the need for PS,intubation and invasive ventilation compared with NCPAP.
5.Prevalence, risk factors, clinical course, and outcome of acute kidney injury in Chinese intensive care units: a prospective cohort study.
Ying WEN ; Li JIANG ; Yuan XU ; Chuan-yun QIAN ; Shu-sheng LI ; Tie-he QIN ; Er-zhen CHEN ; Jian-dong LIN ; Yu-hang AI ; Da-wei WU ; Yu-shan WANG ; Ren-hua SUN ; Zhen-jie HU ; Xiang-yuan CAO ; Fa-chun ZHOU ; Zhen-yang HE ; Li-hua ZHOU ; You-zhong AN ; Yan KANG ; Xiao-chun MA ; Xiang-you YU ; Ming-yan ZHAO ; Xiu-ming XI ; Bin DU ; null
Chinese Medical Journal 2013;126(23):4409-4416
BACKGROUNDAcute kidney injury (AKI) has been recognized as a major healthcare problem affecting millions of patients worldwide. However, epidemiologic data concerning AKI in China are still lacking. The objectives of this study were to characterize AKI defined by RIFLE criteria, assess the association with hospital mortality, and evaluate the impact of AKI in the context of other risk factors.
METHODSThis prospective multicenter observational study enrolled 3,063 consecutive patients from 1 July 2009 to 31 August 2009 in 22 ICUs across mainland China. We excluded patients who were admitted for less than 24 hours (n = 1623), younger than 18 years (n = 127), receiving chronic hemodialysis (n = 29), receiving renal transplantation (n = 1) and unknown reasons (n = 28). There were 1255 patients in the final analysis. AKI was diagnosed and classified according to RIFLE criteria.
RESULTSThere were 396 patients (31.6%) who had AKI, with RIFLE maximum class R, I, and F in 126 (10.0%), 91 (7.3%), and 179 (14.3%) patients, respectively. Renal function deteriorated in 206 patients (16.4%). In comparison with non AKI patients, patients in the risk class on ICU admission were more likely to progress to the injury class (odds ratio (OR) 3.564, 95% confidence interval (CI) 1.706 - 7.443, P = 0.001], while patients in the risk class (OR 5.215, 95% CI 2.798-9.719, P < 0.001) and injury class (OR 13.316, 95% CI 7.507-23.622, P < 0.001) had a significantly higher probability of deteriorating into failure class. The adjusted hazard ratios for 90-day mortality were 1.884 for the risk group, 3.401 for the injury group, and 5.306 for the failure group.
CONCLUSIONSThe prevalence of AKI was high among critically ill patients in Chinese ICUs. In comparison with non-AKI patients, patients with RIFLE class R or class I on ICU admission were more susceptibility to progression to class I or class F. The RIFLE criteria were robust and correlated well with clinical deterioration and mortality.
Acute Kidney Injury ; epidemiology ; etiology ; pathology ; Adult ; Aged ; China ; epidemiology ; Female ; Humans ; Intensive Care Units ; statistics & numerical data ; Male ; Middle Aged ; Prospective Studies ; Risk Factors
6.Differential gene expressions in the stromal cells of the human prostate peripheral zone in males of different ages.
Yong-Chuan WANG ; Jing DU ; Hai-Zhen ZUO ; Hong-Kai LU ; Hai-Tao LIU ; Bang-Min HAN ; Shu-Jie XIA
National Journal of Andrology 2012;18(12):1078-1082
OBJECTIVETo study the gene expressions in the stromal cells of the human prostate peripheral zone (PZ) in men of different ages.
METHODSWe primarily cultured stromal cells from the normal prostate PZ of men aged 23 -32 (young group) and 56 -75 years (old group), profiled the gene signature of the PZ cells by cDNA microarray, and defined the differential gene expression patterns by hierarchical cluster analysis. Among the differential genes, we selected and confirmed up-regulated genes by quantitative real time PCR (Q-PCR), and identified their protein coding by Western blotting.
RESULTSThere were significant differences in the gene expressions of the PZ cells between the old and young groups. Based on the fold change ratio of > or = 2 or < or = 0.5, 509 up-regulated and 188 down-regulated genes were selected in the PZ cells. A subset of significantly differential genes influencing the growth of adjacent epithelial cells were identified, including HGF, IGF2, IGFBP5 and MMP1 in the old males.
CONCLUSIONStromal cells in the prostate PZ were more active in older males in promoting the malignant progression of adjacent prostate epithelial cells, which might be due to the increased expression of extracellular paracrining mediators.
Adult ; Age Factors ; Aged ; Cell Proliferation ; Cells, Cultured ; Gene Expression ; Gene Expression Profiling ; Humans ; Male ; Middle Aged ; Prostate ; metabolism ; Stromal Cells ; metabolism ; Young Adult
7.Benzo (a) pyrene-induced human embryo lung cell cycle alterations through positive regulation of mitogen-activated protein kinase signal pathways.
Hong-ju DU ; Ning TANG ; Bing-ci LIU ; Xiang-lin SHI ; Chuan-shu HUANG ; Ai GAO ; Fu-hai SHEN ; Meng YE ; Bao-rong YOU
Chinese Journal of Preventive Medicine 2007;41(4):277-280
OBJECTIVETo study the effects of benzo(a)pyrene (BaP) on the cell cycle distribution and activities of mitogen-activated protein kinase (MAPK) signal molecules (ERK1/2, JNK1/2 and p38) in human embryo lung cells (HELF), and to investigate the relationship between alterations of MAPK protein phosphorylation and the cell cycle distributions.
METHODSThe phosphorylation of MAPK were induced by exposing HELF cells to BaP at 0.1, 0.5, 2.5 and 12.5 micromol/L. The phosphorylation and protein expression levels of ERK1/2, JNK1/2 and p38 were determined through western-blotting assay. And the flow cytometry assay was used to measure the cell cycle effects in HELF cells after treatment with 2.5 micromol/L BaP for 24 h.
RESULTSThe phosphorylation levels of ERK1/2, JNK1/2 and p38 were significantly increased through BaP exposure. In addition, the phosphorylation of these three MAPKs has similar alteration pattern. We found that exposure of cells to 2.5 microM of BaP for 24 h resulted in a decrease of G(0) and G(1) population by 11.9% (F = 41.38, P < 0.01) and an increase of S population by 17.2% (F = 68.13, P < 0.01). Three chemical inhibitors of MAPK (AG126, SP600125 and SB203580) could significantly inhibit the cell cycle alteration because of BaP treatment.
CONCLUSIONERK1/2, JNK1/2 and p38 could positively regulate the BaP independently induced cell cycle alterations.
Benzo(a)pyrene ; toxicity ; Cell Cycle ; drug effects ; Cells, Cultured ; Fibroblasts ; drug effects ; metabolism ; Humans ; JNK Mitogen-Activated Protein Kinases ; metabolism ; Lung ; cytology ; embryology ; MAP Kinase Kinase 4 ; metabolism ; MAP Kinase Signaling System ; drug effects ; Mitogen-Activated Protein Kinase 1 ; metabolism ; Mitogen-Activated Protein Kinase 3 ; metabolism ; Mitogen-Activated Protein Kinase 8 ; metabolism ; Mitogen-Activated Protein Kinase 9 ; metabolism ; Signal Transduction ; drug effects ; p38 Mitogen-Activated Protein Kinases ; metabolism
8.The activation of MAPK/cyclin D1-CDK4 signaling pathway caused by quartz.
Fu-Hai SHEN ; Xue-Yun FAN ; Bing-Ci LIU ; Xiao-Wei JIA ; Ai GAO ; Bao-Rong YOU ; Meng YE ; Hong-Ju DU ; Chuan-Shu HUANG ; Xiang-Lin SHI
Chinese Journal of Industrial Hygiene and Occupational Diseases 2007;25(1):5-10
OBJECTIVESTo study the phosphorylation level of mitogen activated protein kinase (MAPK) in human embryonic lung fibroblasts (HELF), and the expression level of cyclin D1-CDK4 protein in S-HELF and whether the expression level of cyclin D1-CDK4 protein mediated by MAPK/AP-1 signaling pathway in S-HELF.
METHODSTwo kinds of treatment: (1) Cells were harvested after stimulation 2 h for the detection of cytokines. (2) Cells were stimulated by quartz for a long time (2 months) for transformation characters (S-HELF). The MAP kinase was detected by western blot. Cyclin D1 and CDK4 (cyclin dependent kinase 4) proteins was measured by immunocytochemistry. Flow cytometry was used to evaluate the alternation of cell cycle.
RESULTSCrystalline quartz could cause the phosphorylation level of ERKs, p38K, and JNKs in HELF increase. However, activated levels of ERKs and p46 of JNKs increased in S-HELF, and p38K activation decreased, and no effect on activation of p54 of JNKs, as compared with those in parental HELF. Cyclin D1 and CDK4 protein expression levels increased in S-HELF as compared with parental HELF. Inhibition of ERKs activation by AG126, AP-1 by curcumin, and JNKs by SP600125 could reduced the induction of cyclin D1 and CDK4, whereas inhibition of p38K by SB203580 did not show any inhibitory effects on S-HELF.
CONCLUSIONSThe phosphorylation levels of ERK1/2, JNK1/2, and p38 increased in HELF exposed to quartz. The phosphorylation levels of ERK1/2 and JNK1 increased, but the phosphorylation level of p38 decreased in S-HELF. The expression level of cyclin D1-CDK4 protein increased in S-HELF. Overexpression of cyclin D1-CDK4 is due to the activation of ERKs, JNKs/AP-1 signaling pathway in S-HELF.
Cell Line ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 4 ; metabolism ; Fibroblasts ; cytology ; drug effects ; metabolism ; Humans ; Lung ; cytology ; MAP Kinase Signaling System ; drug effects ; Mitogen-Activated Protein Kinases ; metabolism ; Quartz ; toxicity
9.Detection of a new mutation (1343-TT) in the iduronate-2-sulfatase gene from a Chinese patient with mucopolysaccharidosis type II.
Chinese Journal of Pediatrics 2006;44(2):110-113
OBJECTIVEMutations of the iduronate-2-sulfatase (IDS) gene is the ultimate cause of Hunter syndrome. Clarification of the nature of mutations will create a necessary premise for prenatal gene diagnosis. A mucopolysaccharidosis (MPS) type II patient and his parents from an ethnic minority in Yunnan province were studied to identify their possible mutation in IDS gene to establish the basis for prenatal gene diagnosis.
METHODSThe patient was a boy, 6 years and 10 months old. Urine glycosaminoglycans (GAGs) assay was used for preliminary diagnosis of the patient and his parents with the disease. The three related persons' DNA was extracted and the concentration and purity of the DNA were measured after the urine test results confirmed the diagnosis. Polymerase chain reaction-denaturing high performance liquid chromatography (PCR-DHPLC) analysis was performed to detect the position of the mutation around the hot spots of mutation in exon 9, 3, 8 of the IDS gene. DNA bidirectional direct sequencing was applied to analyze the mutation detected by PCR-DHPLC.
RESULTSThe results of GAGs test showed that in the child with MPS, dermatan sulfate (DS) was positive (+++), heparan sulfate (HS) (+++), chondroitin sulfate (CS) and keratan sulfate (KS) were negative (-); while in his parents none of DS, HS, CS and KS was positive. Abnormal peaks in exon 9 of IDS gene shown by PCR-DHPLC were found in the patient. His mother had heterozygotic peaks. A new frame-mutation (1343-TT) in exon 9 of IDS gene of this patient was confirmed by DNA sequencing. The position where mutation occurred was inside codon 407 (TTT), that means two "T" deleted at position 1343 base pair (1343-TT) in cDNA of the IDS gene, caused a new frame-mutation. It caused elongation of the amino acid chain to a terminal codon TGA at position 429. Thus the peptide chain was shortened from 550 to 428 amino acids. The patient is a hemizygote of the mutation and his mother is a heterozygote.
CONCLUSIONA new frame-mutation (1343-TT) on the IDS gene was identified in this study. The patient is a hemizygote and his mother is a heterozygote. The mutation (1343-TT) resulted in loss of 122 amino acids, which probably caused seriously decreased enzyme activity of IDS, and the authors speculate that this mutation may be the pathological basis of the disease. So, if the mother becomes pregnant again, a prenatal gene diagnostic test for the same mutation should be performed. Furthermore, PCR-DHPLC followed by DNA sequencing are effective methods for diagnosis, including prenatal diagnosis of MPS II.
Amino Acid Sequence ; Asian Continental Ancestry Group ; Base Sequence ; Child ; China ; Chromatography, High Pressure Liquid ; Genotype ; Humans ; Iduronate Sulfatase ; genetics ; Male ; Molecular Sequence Data ; Mucopolysaccharidosis II ; diagnosis ; genetics ; Mutation ; Reverse Transcriptase Polymerase Chain Reaction
10.Vitamin C inhibits benzoapyrene-induced cell cycle changes partly via cyclin D1/E2F pathway in human embryo lung fibroblasts.
Ai GAO ; Bing-Ci LIU ; Xiang-Lin SHIT ; Chuan-Shu HUANG ; Xiao-Wei JIA ; Bao-Rong YOU ; Meng YE ; Fu-Hai SHEN ; Hong-Ju DU
Biomedical and Environmental Sciences 2006;19(3):239-244
OBJECTIVETo study the molecular mechanism of the inhibitory effects of vitamin C on benzo[a]pyrene (B[a]P)-induced changes of cell cycle in human embryo lung fibroblast (HELF) cells.
METHODSThe stable transfectants, HELF transfected with antisense cyclin D1 and antisense CDK4, were established. Cells were cultured and pretreated with vitamin C before stimulation with B[a]P for 24 h. The expression levels of cyclin D1, CDK4, E2F1, and E2F4 were determined by Western blot. Flow cytometric analysis was employed to detect the distributions of cell cycle.
RESULTSB[a]P significantly elevated the expression levels of cyclin D1, E2F1, and E2F4 in HELF cells. Vitamin C decreased the expression levels of cyclin D1, E2F1, and E2F4 in B[a]P-stimulated HELF cells. Dose-dependent relationships were not found between the different concentrations of vitamin C (10, 100, 500, 1000, and 5000 micromol/L) and the expression levels of cyclin D1, E2F1, and E2F4 in HELF cells. The expression levels of cyclin D1, E2F1, and E2F4 in B[a]P-treated transfectants were lower than those in B[a]P-treated HELF cells. The expression levels of cyclin D1 and E2F4 treated with vitamin C and antisense cyclin D1 were decreased compared with those treated with antisense cyclin D1 alone. The effects of vitamin C combined with antisense CDK4 on the expression levels of cyclin D1 and E2F1/E2F4 were similar to those of antisense CDK4 alone. B[a]P progressed HELF cells from G1 to S phase. Both vitamin C and antisense cyclin D1 suppressed the changes of cell cycle progressed by B[a]P. However, antisense CDK4 did not attenuate the above changes. Vitamin C combined with antisense CDK4 markedly suppressed B[a]P-induced changes of cell cycle as compared with antisense CDK4. But the inhibitory effects of vitamin C combined with antisense cyclin D1 on B[a]P-induced changes of cell cycle were similar to those of vitamin C alone or antisense cyclin D1 alone.
CONCLUSIONSB[a]P progressed HELF cells from G1 to S phase via intracellular signaling pathway of cyclin D1/E2F. Vitamin C may modulate this signaling pathway to protect cells from injury caused by B[a]P.
Ascorbic Acid ; pharmacology ; Benzo(a)pyrene ; Blotting, Western ; methods ; Cell Cycle ; drug effects ; physiology ; Cells, Cultured ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 4 ; metabolism ; Dose-Response Relationship, Drug ; E2F1 Transcription Factor ; metabolism ; Fibroblasts ; cytology ; drug effects ; metabolism ; G1 Phase ; drug effects ; physiology ; Humans ; Lung ; cytology ; embryology ; RNA, Antisense ; genetics ; S Phase ; drug effects ; physiology ; Transfection ; methods

Result Analysis
Print
Save
E-mail