[Detection of apoptosis genes differentially expressed in patients with different degrees of benzene poisoning by cDNA microarray].

OBJECTIVE: To investigate the differential expression of apoptosis genes in patients with different degrees of benzene poisoning by cDNA microarray. METHODS: Peripheral mononuclear cells were isolated from seven patients with benzene poisoning of different degrees (suspected 1 case, moderate 2, severe 2), and seven age and sex matched normal control subjects. Total RNA was extracted and purified, followed by reverse transcription to cDNAs with concomitant incorporation of fluorescent dCTP (Cy3 or Cy5). Then 177 genes associated with cell apoptosis were hybridized against the cDNAs probes in microarray. Fluorescent signals were scanned to detect apoptosis genes differentially expressed in patients and normal subjects. RESULTS: Forty one genes were found to be differentially expressed between benzene-poisoned patients and normal controls; among the 41 genes, three were up-regulated among patients with mild to moderate degrees of benzene poisoning and one up-regulated among all patients. The total amount of differentially expressed genes of apoptosis decreased with the aggravation of benzene poisoning. CONCLUSIONS: Differential expression of apoptosis genes was found in patients with benzene poisoning, suggesting a role of altered apoptosis in benzene-induced hematotoxicity.

[Analysis on tumor related gene expression profiles in benzene poisoning using cDNA microarray].

OBJECTIVE: To detect target genes for further study by way of analyzing the gene expression profiles of benzene poisoning by using cDNA microarray. METHODS: Peripheral mononuclear cells were isolated from seven patients with benzene poisoning of different degrees, and sevene age-and sex-matched normal subjects. Total RNA was extracted and purified, followed by revese transcription to cDNAs with concomitant incorporation of fluorescent dCTP (Cy3 or Cy5). The cDNAs were used as probes in microarray of 2780 cloned cDNA. Fluorescent signals were scanned to detect genes differentially expressed in patients and normal subjects. RESULTS: Among 7 pieces of cDNA microarray of 2780 tumour related genes, the expression of 16 genes, such as GRO1, TGFBR3, LYN ctc was upregulated, whereas the expression of 28 genes, such as FOSB, DJ-1, MCT-1 etc was down-regulated. CONCLUSION: Abnormal expression of tumour related genes of patients exposed to benzene suggests that they may be the key genes, which play important role in benzene-induced leucocythemia. cDNA microarray technique is useful to indicate the expression mode of benzene poisoning tumour related genes, and to find rapidly and effectively new research object and the way of gene therapy.

[Association of p53, PCNA expression and trace element content in esophageal mucosa].

BACKGROUND & OBJECTIVE: There were abnormal changes of trace element in esophageal cancer patient's hair and serum in the high risk area. But it was still unknown that the relationship between p53 and proliferating cell nuclear antigen(PCNA) expression and the trace element content in varied esophageal mucosa. This study was designed to probe the relationship of trace element content and p53 mutation, PCNA expression in esophgeal mucosa. METHODS: Esophageal biopsy specimen of 151 cases were divided into four groups (normal, esophagitis, dysplasia, and early carcinoma). The quantitative determination of trace element was performed was performed by using X-ray energy spectrometry and the detection of PCNA expression and p53 mutation was performed by using S-P immunohistochemistry method. RESULTS: The contents of Zn, Se, Mo, were 1.74 +/- 0.32, 1.53 +/- 0.64, 0.58 +/- 0.21, 0.20 +/- 0.08; 0.15 +/- 0.06, 0.10 +/- 0.03, 0.04 +/- 0.02, 0; 4.73 +/- 1.31, 3.45 +/- 1.19, 3.51 +/- 1.32, 2.51 +/- 1.04; respectively in four groups. There was a significant difference in varied histological typies(P < 0.05). The contents of Cu/Zn, Ni were 0.57 +/- 0.17, 0.89 +/- 0.18, 2.45 +/- 0.48, 2.92 +/- 1.08; 0.45 +/- 0.05, 1.27 +/- 0.11, 2.46 +/- 0.24, 2.58 +/- 0.33; respectively, which increased gradually in pace with upgrade of esophageal lesions, with significant difference (P < 0.05). The postive rates of p53 and PCNA were 0, 46.15%, 100%; 31.19%, 84.62%, 100% respectively in normal esophageal epithelium, dysplasia, and early carcinoma, with significant difference (P < 0.01), and had significant correlation to trace element. CONCLUSION: The content variation of Zn, Se, Mo, Cu, Ni could be possessed of certain effect on p53 mutation and PCNA overexpression of esophageal epithelium in the high risk area.

Effect of manganese on heat stress protein synthesis of new-born rats.

AIM: To study the effect of manganese (Mn) on heat stress protein 70 (HSP70) synthesis in the brain and liver of new-born rats whose mother-rats were exposed to Mn. METHODS: 32 female rats were randomly divided into four groups. One group was administrated with physiological saline only as control group, the other three groups were administrated with 7.5, 15 and 30 mg x kg(-1) manganese chloride (MnCl2) by intraperitioneal injection every two days for two weeks. After delivery, the mother-rats received MnCl2 unceasingly for a week with the same method. Then the contents of Mn Zn Cu and Fe in the livers of the new-born rats were determined by atomic absorption spectroscopy; The level of HSP70 in the brains and the livers of the new-born rats as detected by Western-dot-blotting, and the SOD activities were measured simultaneously. RESULTS: The contents of Mn in the livers of new-born rats of the experimental groups(respective 1.38+/-0.18, 2.73+/-0.65,3.44+/-0.89 microg x g(-1)) were significantly increased compared with the control group(0.88+/-0.18 microg x g(-1); P<0.01); The contents of Fe in the livers of new-born rats of 15 and 30 mg x kg(-1) experimental groups (426+/-125, 572+/-175 microg x g(-1), respectively) were significantly increased compared with the control group(286+/-42 microg x g(-1); P<0.05); the levels of Zn in the livers of the new-born rats of three experimental groups(254+/-49, 263+/-47, 213+/-28 microg x g(-1), respectively) were lower than those of the control group(335+/-50 microg x g(-1); respective P<0.05, P<0.01); and the levels of Cu showed no significant difference among the four groups(three experimental groups: 75+/-21, 68+/-241 and 78+/-18 microg x g(-1); control group: 83+/-9 microg x g(-1); P<0.05). There was a significant increase in the levels of HSP70 in the brains of new-born rats of the 30 mg x kg(-1) group (19.5 x 10(3)+/- 1.3 x 10(3)A;control group:14.3 x 10(3)+/-1.4 x 10(3)A; P<0.01) and the levels of HSP70 in the livers of new-born rats of three experimental groups(respective 19.6 x 10(3)+/- 3.9 x 10(3)A,18.5 x 10(3)+/-3.8 x 10(3)A, 22.4 x 10(3)+/-1.9 x 10(3)A) also increased than control group(13.3 x 10(3)+/-1.0 x 10(3)A;P<0.01), but the SOD activities showed no significant difference among brains of the four groups (experimental groups: 5.04+/-0.43, 4.83+/-0.48, 4.60+/-0.84 ku x g(-1); control group: 4.91+/-0.37 ku x g(-1); P<0.05). The SOD activities in the livers of 15 mg x kgP< group(5.41+/-0.44 ku x gP<) was lower than the control group(5.95+/-0.36 ku x gP<; P<0.05). CONCLUSION: While mother-rats were exposed to manganese, the metabolisms of Mn Zn and Fe of new-born rats in the livers were influenced and were situated in a stress status, thus HSP70 syntheses is induced in the brains and livers of new-born rats, but the mechanism of this effect in the developmental toxicity of Mn remains to be further studied.