Chromosomal aberrations in lymphocytes of lung cancer patients treated with carbon ions

The purpose of this study is to investigate the normal tissue damage caused by carbon-ion therapy. We measured chromosomal aberrations in peripheral blood lymphocytes before, during, and after radiotherapy, using the techniques of fluorescence in situ hybridization (FISH) and chemically induced premature chromosome condensation (PCC). Twenty-two lung cancer patients treated at HIMAC (Heavy Ion Medical Accelerator in Chiba) entered the study and signed an informed consent. Frequencies of lymphocytes with chromosomal aberrations at the end of carbon-ion therapy varied among the patients. This frequency was significantly correlated to the radiation field size and weakly correlated to the counts of white blood cells and lymphocytes during the treatment. As a result, we have found that chromosomal aberrations in peripheral blood lymphocytes from patients treated for lung cancer by carbon-ions were dependent on target volume, possibly reflecting the increased involvement of lymph nodes in the target field.     

Chromosomal aberrations in lymphocytes of pharmaceutical factory workers

Chromosomes were analyzed in peripheral lymphocytes of 31 male workers who were exposed to sulfonamide drugs in a pharmaceutical factory. The number of cells with structural chromosomal aberrations was significantly increased as compared to 15 unexposed individuals (controls). The chromosomal damage observed was mainly gaps and breaks.     

某金矿井下作业人员淋巴细胞染色体畸变分析

目的 分析某金矿井下作业人员外周血淋巴细胞染色体畸变情况,为进一步控制职业危害提供科学依据.方法 采用现况调查的流行病学研究方法,用常规染色体畸变分析法检测58例金矿井下作业人员(暴露组)和62例对照组人员的染色体畸变情况.用LD-P-R-T型氡射气探测器,内置固体径迹探测器CB-39测量井下累积~(222)Rn浓度和γ空气比释动能率.结果 井下作业人员染色体型畸变率为0.72%,染色单体型畸变率为0.41%,总畸变率为1.16%,对照组的染色体型畸变率为0.14%,染色单体型畸变率为0.18%,总畸变率为0.32%,两组比较,差异有统计学意义(P<0.01);井下工作人员各工龄组染色体型畸变率和总畸变率均明显高于对照组,差异有统计学意义(P<0.05),21～年工龄组染色体犁畸变率(1.20%)明显高于1～年工龄组(0.14%),差异有统计学意义(P<0.05).染色体畸变类型主要是以无着丝粒断片为主.金矿井下累积~(222)Rn浓度平均值为1200 Bq/m~3,井下γ空气比释动能率与地面辐射水平接近.结论 金矿井下作业人员存在不同程度的细胞遗传学损伤效应,应进一步采取预防措施,加强职业危害控制.     

Chromosomal aberrations and cancer risk: results of a cohort study from Central Europe

A high level of chromosomal aberrations in peripheral blood lymphocytes may be an early marker of cancer risk, but data on risk of specific cancers and types of chromosomal aberrations (chromosome type and chromatid type) are limited. A total of 6,430 healthy individuals from nine laboratories in Croatia, Hungary, Lithuania, Poland, and Slovakia, included in chromosomal aberration surveys performed during 1978-2002, were followed up for cancer incidence or mortality for an average of 8.5 years; 200 cancer cases were observed. Compared with that for the low-tertile level of chromosomal aberrations, the relative risks of cancer for the medium and high tertiles were 1.78 (95% confidence interval: 1.19, 2.67) and 1.81 (95% confidence interval: 1.20, 2.73), respectively. The relative risk for chromosome-type aberrations above versus below the median was 1.50 (95% confidence interval: 1.12, 2.01), while that for chromatid-type aberrations was 0.97 (95% confidence interval: 0.72, 1.31). The analyses of risk of specific cancers were limited by small numbers, but the association was stronger for stomach cancer. This study confirms the previously reported association between level of chromosomal aberrations and cancer risk and provides novel information on the type of aberrations more strongly predictive of cancer risk and on the types of cancer more strongly predicted by chromosomal aberrations.     

Chromosomal aberrations in peripheral lymphocytes of cotton field workers exposed to pesticides

Fifty-two pesticide sprayers in cotton fields were selected for the analysis of chromosomal aberrations in peripheral lymphocytes. Twenty-five samples were collected from healthy males who were not exposed to pesticides. Statistical analysis revealed that there was a significant increase in chromosomal aberrations in the exposed population compared to controls. Total chromosomal aberrations increased irrespective of duration of exposure.     

Incidence of somatic mutations of the lymphocytes in subjects working in an environment with cancer risk

A total of 417 individuals were examined by the Strauss-Albertini method, which is useful to detect the lack of hypoxanthin-guanine-phosphoribosil-transferase (HPRT) located on the X-chromosome. The damage of this locus leads to the loss of the sensitivity of the T-lymphocytes to 6-thioguanine (TG) therefore in the presence of this antimetabolite (TG) the cells will respond to the lectin's (phytohaemagglitinine: PHA) growth stimulatory effect. This defect in the cells can cause mutation, making the cells to be resistant against TG-treatment and during their blastogenesis they will be able to incorporate 3 (H)-thymidine. The number of these labeled cells will give the frequency of the mutant (TG-resistant) cells. The results showed a significant elevation in the number of TG-resistant lymphocytes among uranium miners and among industrial workers exposed to different mutagenic or carcinogenic chemicals when compared to the negative controls. The mutation frequency was elevated also among primary lung cancer patients (positive controls) up to the level measured among industrial workers.     

Selenium status and cardiovascular risk factors in healthy Dutch subjects

To provide further insight into the possible role of selenium in cardiovascular disease, we examined the relationship between cardiovascular risk factors, some nutritional parameters, and short- and long-term selenium status. A total of 82 healthy Dutch volunteers, 59 men and 23 women, aged 40-75 years, were studied. Means and standard deviations of selenium parameters were: plasma selenium 106.4 +/- 23.7 micrograms/L, erythrocyte selenium 0.59 +/- 0.19 microgram/g Hb, toenail selenium 0.78 +/- 0.17 ppm, and erythrocyte glutathione peroxidase activity 28.0 +/- 8.1 U/g Hb. No association was found between selenium status and gender, age, serum total-, LDL-, and HDL-cholesterol, systolic and diastolic blood pressure, alcohol intake, and body mass index. A significantly lower plasma selenium level was observed among smokers compared to nonsmokers (101.0 micrograms/L, SE = 3.9 vs 112.0 micrograms/L, SE = 3.6, p = 0.04). A significant negative association was found between erythrocyte selenium and serum levels of vitamin A and ferritin. No relevant relationship was observed between selenium status and serum fatty acid composition, vitamin E, vitamin B6, and iron. Apart from an association between smoking and short-term selenium status, we found no indications that a possible effect of selenium on cardiovascular disease may operate through the known risk factors.     

Selenium status and cardiovascular risk factors in healthy Dutch subjects.

To provide further insight into the possible role of selenium in cardiovascular disease, we examined the relationship between cardiovascular risk factors, some nutritional parameters, and short- and long-term selenium status. A total of 82 healthy Dutch volunteers, 59 men and 23 women, aged 40-75 years, were studied. Means and standard deviations of selenium parameters were: plasma selenium 106.4 +/? 23.7 micrograms/L, erythrocyte selenium 0.59 +/? 0.19 microgram/g Hb, toenail selenium 0.78 +/? 0.17 ppm, and erythrocyte glutathione peroxidase activity 28.0 +/? 8.1 U/g Hb. No association was found between selenium status and gender, age, serum total-, LDL-, and HDL-cholesterol, systolic and diastolic blood pressure, alcohol intake, and body mass index. A significantly lower plasma selenium level was observed among smokers compared to nonsmokers (101.0 micrograms/L, SE = 3.9 vs 112.0 micrograms/L, SE = 3.6, p = 0.04). A significant negative association was found between erythrocyte selenium and serum levels of vitamin A and ferritin. No relevant relationship was observed between selenium status and serum fatty acid composition, vitamin E, vitamin B6, and iron. Apart from an association between smoking and short-term selenium status, we found no indications that a possible effect of selenium on cardiovascular disease may operate through the known risk factors.     

肿瘤患者及健康人血清硒水平研究

对２０３例肿瘤患者和４０例健康对照组血清硒研究表明，肿瘤患者血清硒显著低于健康组（Ｐ＜０．０１～０．００１），而不同肿瘤患者之间无差异，肺癌患者不同分期之间也无统计学意义，结果认为低硒水平可能是肿瘤患者的固有特性。     

阜阳市医用X线工作者染色体畸变分析

低剂量电离辐射可引起细胞遗传学等方面的改变[1]。为了解本地区放射工作人员的健康状况，我们对阜阳市445名放射工作人员作健康体检，并进行了染色体畸变(Chromosomal aberration)分析。     

Effect of low-fat, high-fat, and fiber-supplemented high-fat diets on colon cancer risk factors in feces of healthy subjects.

Normal healthy volunteers (n = 8) received low- and high-fat (14% and 53% energy/day, respectively) and dietary fiber-supplemented high-fat diets (fiber 25 g/day, fat 52% energy/day) for 10 days each. Colon cancer risk factors in feces were measured by colonic nuclear aberration assay, the Ames Salmonella test using strain TA100, and measurement of bile acids and calcium soaps. Nuclear aberrations in colonic epithelium increased during the high-fat diet period and then decreased during the fiber-supplemented high-fat diet period. There were no significant differences in the mutagenicity on Salmonella TA100 or in the concentration of bile acids during the high-fat diet period. Bile acids decreased during the fiber supplementation period. The marked increase in calcium soaps during the high-fat diet period indicates an increase in long-chain fatty acids in the fecal lipid component and conversion of these fatty acids to insoluble calcium soaps when enough calcium is present.     

Chromosome aberrations in lymphocytes of nurses handling cytostatic agents

In an evaluation of the possible chromosome damage caused by cytostatic agents 11 nurses with long-term exposure to such agents were studied. Five laboratory workers and 11 hospital clerks served as referents. The number of chromosomally aberrant lymphocytes was significantly higher in the group of nurses than in the group of laboratory workers or hospital clerks. The number of chromosome-type breaks was increased significantly among the nurses as compared to the reference groups. There was no significant difference in the number of chromatid-type breaks between the groups. The observed increase in chromosome-type aberrations may have been due to long-term occupational exposure to cytostatic agents.     

Intra- and interindividual variability in lymphocyte chromosomal aberrations: implications for cancer risk assessment

Chromosomal aberration frequency in peripheral lymphocytes of healthy individuals has been found to be predictive of future cancer risk. The variability of chromosomal aberrations over time, which is largely unknown, should be clarified to interpret the strength of this association and to determine its use in cancer prediction. Intra- and interindividual variability in chromosomal aberration frequency was therefore determined. From a pooled database comprising 11 national cohorts (1965-2002), the authors included 9,433 blood samples from 3,550 subjects with at least one repeated chromosomal aberration measurement. The generalized concordance correlation coefficient of 0.19 was low, indicating high intraindividual variability compared with interindividual variability, resulting in a high likelihood of misclassification. The relation between chromosomal aberration frequency and future cancer risk has probably been underestimated in previous studies. A single chromosomal aberration measurement seems not to be representative of the whole lifespan level of chromosome instability and greatly limits the use of chromosomal aberration frequency-as measured with Giemsa staining-for individual risk assessment.     

Smoking intervention in subjects at risk of asbestos-related lung cancer

A smoking intervention counseling program was applied among asbestos-exposed male smokers younger than 65 years of age to examine the effect of an intervention based on risk communication. Intervention subjects (n = 431) were invited to a health status checkup combined with physician-delivered smoking intervention counseling. Control subjects (n = 141) received no intervention. After 1 year, 5% of the responders in the intervention group, versus 3.4% in the control group, had stopped smoking. Corresponding conservative estimates were 3.5% and 2.6%, respectively. The quitters had been exposed to a higher “dose” of asbestos but had smoked less, and for a shorter period, than had the continuing smokers. Counseling by a general physician increased successful quitting threefold, compared to counseling by a physician in a specialized institution. These results suggest a potential for smoking cessation among subjects at high risk of lung cancer due to asbestos exposure. General practice care may be an appropriate setting both for identification of such subjects and for intervention. Am. J. Ind. Med. 31:705–712, 1997. © 1997 Wiley-Liss, Inc.     

Drinking beer reduces radiation-induced chromosome aberrations in human lymphocytes

We here investigated and reported the effects of beer drinking on radiation-induced chromosome aberrations in blood lymphocytes. Human blood that was collected either before or after drinking a 700 ml beer was in vitro irradiated with 200 kVp X rays or 50 keV/microm carbon ions. The relation between the radiation dose and the aberration frequencies (fragments and dicentrics) was significantly (p < 0.05) lower for lymphocytes collected 3 h after beer drinking than those before drinking. Fitting the dose response to a linear quadratic model showed that the alpha term of carbon ions was significantly (p < 0.05) decreased by beer drinking. A decrease of dicentric formation was detected as early as 0.5 h after beer drinking, and lasted not shorter than 4.5 h. The mitotic index of lymphocytes was higher after beer drinking than before, indicating that a division delay would not be responsible for the low aberrations induced by beer drinking. An in vitro treatment of normal lymphocytes with 0.1 M ethanol, which corresponded to a concentration of 6-times higher than the maximum ethanol concentration in the blood after beer drinking, reduced the dicentric formation caused by X-ray irradiation, but not by carbonion irradiation. The beer-induced reduction of dicentric formation was not affected by serum. It is concluded that beer could contain non-ethanol elements that reduce the chromosome damage of lymphocytes induced by high-LET radiation.