Deletions of the YNZ22and Alu-VpA/MycL1Loci and Post-Surgery Prognosis in Human Colorectal Adenocarcinoma

Since deletions of the short arm of chromosome 17 are the most common genetic defects in human colorectal carcinoma (CC), we tested the YNZ22locus (D17S30, 17p13.3) for loss of heterozygosity (LH) in adenocarcinoma and in the normal colonic mucosa of 49 CC patients, and studied the association of LH with clinicomorphological features of the tumor. Allele frequency distribution of YNZ22did not differ for the patients and healthy people. LH in YNZ22in the tumor was found in 33% (13/39) of all informative cases, its frequency being thrice higher in men than in women (²= 5.21, p= 0.022). The defect was associated with moderate or poor histological differentiation (P ₂= 0.0055) and polyploidy >3n(P ₂= 0.0035) of tumor cells and with high incidence of post-surgery relapse or metastasis. Analysis of both YNZ22and Alu-VpA/MycL1(1p34.3) loci in the tumor allowed reliable relapse prognosis in 76% of the CC patients. The probability of post-surgery relapse or metastasis was estimated at no less than 67% for patients with LH in at least one of the two loci in the tumor, and at somewhat more than 20% for patients without LH.     

Deletion of YNZ22 and ALU-VPA/MYCL1 loci in human colonic adenocarcinoma and postoperative prognosis

Since deletions of the short arm of chromosome 17 are the most common genetic defects in human colorectal carcinoma (CC), we tested the YNZ22 locus (D17S30, 17p13.3) for loss of heterozygosity (LH) in adenocarcinoma and in the normal colonic mucosa of 49 CC patients, and studied the association of LH with clinicomorphological features of the tumor. Allele frequency distribution of YNZ22 did not differ for the patients and healthy people. LH in YNZ22 in the tumor was found in 33% (13/39) of all informative cases, its frequency being thrice higher in men than in women (chi 2 = 5.21, p = 0.022). The defect was associated with moderate or poor histological differentiation (P2 = 0.0055) and polyploidy > 3n (P2 = 0.0035) of tumor cells and with high incidence of post-surgery relapse or metastasis. Analysis of both YNZ22 and Alu-VpA/MycL1 (1p34.3) loci in the tumor allowed reliable relapse prognosis in 76% of the CC patients. The probability of post-surgery relapse or metastasis was estimated at no less than 67% for patients with LH in at least one of the two loci in the tumor, and at somewhat more than 20% for patients without LH.     

Detection of chromosomal aneuploidy in endometriosis by multi-color fluorescence in situ hybridization (FISH)

Endometriosis affects 10–15% of women of reproductive age and is a common cause of infertility and pelvic pain. Although endometriosis is characterized by abnormal growth or turn-over of cells, the genetic changes involved remain unclear. We employed a multi-color fluorescence in situ hybridization (FISH) strategy to determine the incidence of somatic chromosomal numeric alterations in severe/late stage endometriosis. Using alpha-satellite sequence-specific DNA probes for chromosomes 7, 8, 11, 12, 16, 17, and 18, simultaneous two- and three-color FISH were performed to evaluate the frequency of monosomic, disomic, and trisomic cells in normal control and endometriotic tissue specimens. In one of four endometriosis samples studied, a significantly higher frequency of monosomy for chromosome 17 (14.8%, χ² ₄ = 53.3, P < 0.0001) and 16 (8.8%, χ² ₄ = 11.4, P < 0.05) was observed. An increased number of cells with chromosome 11 trisomy (14.8%, χ² ₄ = 96.2, P < 0.0001) were detected in a second case. In a third case, a distinct colony of nuclei with chromosome 16 monosomy (14.1%, χ² ₄ = 21.39, P < 0.005) was detected. Acquired chromosome-specific aneuploidy may be involved in endometriosis, reflecting clonal expansion of chromosomally abnormal cells. That candidate tumor suppressor genes and oncogenes have been mapped to chromosomes 11, 16, and 17 suggests that chromosomal loss or gain plays a role in the development and/or progression of endometriosis. Received: 27 December 1997 / Accepted: 14 April 1997     

Genetic polymorphism of <Emphasis Type="Italic">GSTT1</Emphasis> may be under natural selection in a population chronically exposed to natural sour gas

Objective In order to examine whether chronic exposure to natural sour gas containing sulfur compounds act as natural selection force on genetic polymorphisms of glutathione S-transferase M1 (GSTM1) and T1 (GSTT1), the present study was done. Methods The study was performed on two groups of healthy individuals of Masjid-i-Sulaiman (Khozestan province, southwest of Iran) citizens with the mean ages of 47.5 ± 12.4 (36 male and 58 female) and 16.3 ± 2.4 (47 male and 140 female) that were considered as first and second generation, respectively. The GSTT1 and GSTM1 genotypes were determined using a PCR-based method. Results The genotypic frequencies of GSTM1 did not change significantly (χ² = 0.085, df = 1, P = 0.770). The frequency of the GSTT1 null genotype was 52.1% in the first generation and reached to 36.4% in the second generation. There was significant difference between two generations for the GSTT1 polymorphism (χ² = 6.397, df = 1, P = 0.011). Conclusion It was suggested that the GSTT1 polymorphism may be under natural selection because of probably favored ability of GSTT1-active genotype to survival and reproduction.     

Intratumor heterogeneity of chromosome 1, 7, 17, and 18 aneusomies obtained by FISH and association with flow cytometric DNA index in human colorectal adenocarcinomas

BACKGROUND: The origin and evolution of somatic chromosome aberrations in colorectal cancer is still poorly understood. The data in the literature suggest that some specific chromosome aberrations are more common. It is not known, however, if there is a correlation of these with near-diploid and high aneuploidy previously proposed to be a characteristic of the adenoma-carcinoma sequence. METHODS: Chromosome 1, 7, 17 and 18 numerical aberrations and 1p deletions were evaluated by fluorescence in situ hybridization analysis for 20 human sporadic colorectal adenocarcinomas in 70 distinct tumor sectors and correlated with flow cytometric DNA index (DI) values. RESULTS: Aneusomy for at least one of the investigated chromosomes was observed in 60 of 70 tumor sectors corresponding to 19 of 20 adenocarcinomas (95%). Deletions at 1p, observed in 8 of 18 adenocarcinomas (44%), were intratumor homogeneous in 7 of 8 tumors. In contrast, the other aberrations were intratumor heterogeneous. Aneusomies of chromosomes 1, 7, and 17 were strongly associated with DNA high aneuploidy (DI > or = 1.4), whereas aneusomy of chromosome 18 and 1p deletions were equally common among DNA diploid and near-diploid tumors (DI < 1.4 and DI not equal to 1). CONCLUSIONS: Overall, these data suggest the existence of different aneuploidization routes correlated with specific chromosome aberrations. In addition, intratumor homogeneity of 1p deletions appears to be an indication of early occurrence or strong selection. We also suggest that tumors with monosomies and in particular monosomies-trisomies for the same chromosomes support a model of aneuploidization and chromosome instability during the colorectal tumor progression based on loss of symmetry during chromosome segregation (Giaretti: Lab Invest 71:904-910, 1994).     

Methylation of the Putative Tumor Suppressor Gene RASSF1A in Primary Cervical Tumors

Methylation-sensitive restriction endonuclease analysis (MSRA) followed by polymerase chain reaction (PCR) have been used to estimate the methylation level of 13 CpG dinucleotides in the promoter region of the putative suppressor gene RASSF1A (3p21.31) in squamous cell carcinomas of the uterine cervix (SCCs) carrying human papillomavirus (HPV) types 16, 18, and related types. Methylation of 3 to 13 CpG pairs has been found in 64% (25 out of 39) tumor DNA samples, 22% (2 out of 9) DNA samples from morphologically normal tissues adjacent to the tumor (P = 0.0306), and two out of three DNA samples from peripheral blood leukocytes of carcinoma patients. These CpG pairs are not methylated in the DNA of leukocytes of healthy donors (0 out of 10). The methylation level of the RASSF1A promoter region studied in tumors of the patients with regional lymph node metastases is significantly higher than in tumors of the patient that have no metastases (P = 8.5 × 10^–12). The methylation frequency of gene RASSF1A is two times higher than the frequency of hemi- and homozygous deletions in the chromosome 3 region where the gene is located. The data obtained indicate that methylation is one of the main mechanisms of the RASSF1A gene inactivation in HPV-positive human cervical tumors. The methylation of this gene may be an early event in the genesis of cervical tumors, the methylation level increasing with tumor progression.     

Genetic analysis of the X-chromosomal region 1E-2A of Drosophila melanogaster

Reversion mutagenesis of three single P elements located in the cytogenetic interval 1E-2A at the tip of the X chromosome of Drosophila melanogaster was used to recover new deletions in this chromosomal region. The deletions obtained include small aberrations within region 2A and larger lesions extending from 2A into 1E and 1B. All three screens also yielded terminal deficiencies. The new deficiencies, together with previously characterized rearrangements, were analyzed for their complementation behaviour with the maternal effect locus fs(1)Nasrat and lethal loci in the region. These analyses provide an overall genetic map of the interval 1E-2A. In addition, the smaller deletions were physically mapped within cloned genomic DNA of the 2A region.     

Absence ofGABRA1 Ala322Asp mutation in juvenile myoclonic epilepsy families from India

An Ala322Asp mutation in theGABRA1 gene was recently reported to be responsible for causing the autosomal dominant (AD) form of juvenile myoclonic epilepsy (JME) in a French-Canadian family. To study if JME families from India exhibiting the AD mode of inheritance carry the Ala322Asp mutation, we examined 35 unrelated JME-affected individuals from such families for the Ala322Asp mutation inGABRA1. Ala322Asp mutation was not observed in any of these JME-affected individuals, suggesting that this mutation is unlikely to be a predominant mutation involved in causation of epilepsy. To evaluate the possibility of other mutation(s) in and aroundGABRA1 that may predispose to JME, we compared the allele frequencies at two marker loci, D5S2118 and D5S422, flankingGABRA1, in probands and 100 matched population controls. One of the allele frequencies at D5S422 shows a significant difference between the cases and controls (χ² = 11.44, d.f. = 1,P = 0.0007), suggesting genetic association between JME and genes located in the proximity of the DNA marker.     

From Identification of Genomic Polymorphisms to Diagnostic and Prognostic Markers of Human Epithelial Tumors

The review considers the results obtained by several groups in the fields of identification of polymorphic loci in the human genome, localization and analysis of genes associated with epithelial tumors of various origins, and generation of molecular markers of socially important oncological diseases. In the first two cases, work was initiated and supported by the Russian program Human Genome. To find new polymorphic loci in the human genome, di-, tri-, and tetranucleotide repeats were searched for in an ordered cosmid library of chromosome 13, NotI and cosmid clones of chromosome 3, and in brain EST. In total, nine polymorphisms and almost 200 STS were identified. Markers of NotI clones of chromosome 3 were associated with particular genes. Polymorphic loci NL1-024, NL2-007, and EST04896 were employed in analysis of deletions from chromosome 3p in tumor DNA. Deletion mapping of 3p in epithelial tumors of five types revealed six critical regions containing potential tumor suppressor genes. Of these, two were in the distal region of chromosome 3p and four, in region 3p21.3. A significant correlation was observed for the frequency of allelic deletions and the stage and the grade of tumors (P < 0.05). On the strength of these findings, genes of region 3p were associated with both tumor development and progression, and proposed as prognostic markers. Regions LUCA and AP20 (3p21.3) showed a high (90%) frequency of aberrations, including homozygous deletions in almost 20% cases. The peak of allelic deletions from region D3S2409–D3S3667 (600 kb) was statistically valid (P = 10^–3). Regions AP20 and D3S2409–D3S3667 (3p21.3) were for the first time associated with tumorigenesis. Clusters of tumor suppressor genes were identified in regions LUCA, AP20, and D3S2409–D3S3667. Methylation of RASSF1A and RAR-beta2 (3p) was associated with early carcinogenesis, and that of SEMA3B, with tumor progression. These findings are useful for early diagnostics and post-surgery prognosis of tumors.     

Glutathione S-Transferase M1, T1, P1 Genotypes and Risk for Development of Colorectal Cancer

The glutathione S-transferase (GST) supergene family is an important part of cellular enzyme defense against endogenous and exogenous chemicals, many of which have carcinogenic potential. The present investigation was conducted to detect a possible association between polymorphisms at the GSTM1, GSTT1, and GSTP1 genes and the interaction with cigarette smoking and colorectal cancer incidence. We examined 181 patients with colorectal cancer and 204 controls. DNA was extracted from whole blood, and the GSTM1, GSTT1, and GSTP1 polymorphisms were determined using a real-time polymerase chain reaction and fluorescence resonance energy transfer with a Light-Cycler instrument. Associations between specific genotypes and the development of colorectal cancer were examined by use of logistic regression analysis to calculate odds ratios (OR) and 95% confidence intervals (CI). The GSTM1 polymorphism was associated with an increased risk of developing colorectal cancer (OR = 1.62, 95% CI: 1.06–2.46). Also the risk of colorectal cancer associated with the GSTT1 null genotype was 1.64 (95% CI: 1.10–2.59). Statistically no differences were found between patients with colorectal cancer and control groups for the GSTP1 Ile/Ile, Ile/Val and Val/Val genotypes. In addition, the frequencies of the GSTM1 and GSTT1 deletion genotypes differed significantly between the cases and controls for current smokers; the GSTT1 null genotype especially is associated with a greater risk of colorectal cancer (OR = 2.44, 95% CI: 1.24–4.81). The GSTM1 and GSTT1 deletions were associated with an increased risk of developing a transverse or rectal tumor (OR = 1.86, 95% CI: 1.15–3.00; OR = 1.70, 95% CI: 1.02–2.84; respectively). The glutathione S-transferase polymorphisms were not associated with risk in patients stratified by age. The risk of colorectal cancer increased as putative high-risk genotypes increased for the combined genotypes of GSTM1 null, GSTT1 null, and either GSTP1 valine heterozygosity or GSTP1 valine homozygosity (OR = 2.69, 95% CI: 1.02–7.11). In conclusion, the results obtained in this study clearly suggest that those susceptibility factors related to different GST polymorphic enzymes are predisposing for colorectal cancer.     

Gamete composition and chromosome variation in pollen-derived plants from octoploid triticale x common wheat hybrids

Summary Anther culture of secondary octoploid triticale (AABBDDRR) and F₁ hybrids (AABBDDR) of octoploid triticale x common wheat crosses was carried out, and 96 pollen-derived plants were developed and studied cytologically. In addition to the 8 types of pollen-derived plants with the theoretically predicted chromosome number, plants with the chromosome constitutions of 2n = 38, 43, 45, 47, 74, and mixoploids were obtained. The haploids and the diploids had different distributions. The frequencies of plants with one and two (pairs of) rye chromosomes were extremely high, and anther culture may be an expeditious route for creating alien addition lines of distant hybrid F₁s. Chromosome aberrations, including deletions, inversions, translocations, as well as isochromosomes and ring chromosomes, were observed in some plants. Abnormal meioses, such as chromosome non-disjunction, were also found. The reasons for the chromosome aberrations are discussed.     

Opposite effect of ERK1/2 and JNK on p53-independent p21 WAF1/CIP1 activation involved in the arsenic trioxide-induced human epidermoid carcinoma A431 cellular cytotoxicity

Summary While arsenic trioxide (As₂O₃) is an infamous carcinogen, it is also an effective chemotherapeutic agent for acute promyelocytic leukemia and some solid tumors. In human epidermoid carcinoma A431 cells, we found that As₂O₃ induced cell death in time- and dose-dependent manners. Similarly, dependent regulation of the p21 ^WAF1/CIP1 (p21) promoter, mRNA synthesis, and resultant protein expression was also observed. Additionally, transfection of a small interfering RNA of p21 could block the As₂O₃-induced cell growth arrest. The As₂O₃-induced p21 activation was attenuated by inhibitors of EGFR and MEK in a dose-dependent manner. Using a reporter assay, we demonstrated the involvement of the EGFR-Ras-Raf-ERK1/2 pathway in the promoter activation. In contrast, JNK inhibitor enhanced the As₂O₃-induced p21 activation, also in a dose-dependent fashion. Over-expression of a dominant negative JNK plasmid likewise also enhanced this activation. Furthermore, MEK inhibitor attenuated the anti-tumor effect of As₂O₃. In contrast, in combination with JNK inhibitor and As₂O₃ enhanced cellular cytotoxicity. Therefore, we conclude that in A431 cells the ERK1/2 and JNK pathways might differentially contribute to As₂O₃-induced p21 expression and then due to cellular cytotoxicity.     

RB1 and CDKN2A Functional Defects Resulting in Retinoblastoma

Multiplex methylation-sensitive PCR was employed in studying the methylation of the RB1 and CDKN2A/p16 promoter regions in 52 retinoblastomas. Aberrant methylation inactivating RB1 was detected in 14 (27%) tumors. Methylation of p16 was for the first time observed in retinoblastoma (9 tumors, 17%). Both promoters proved to be methylated in two tumors. In four tumors, aberrant methylation was combined with structural defects of both RB1 alleles. Aberrant methylation of the p16 promoter was the second mutation event in two tumors and was not accompanied by RB1 defects in one tumor. Complex testing for RB1 mutations, loss of heterozygosity, and functional inactivation of the two genes revealed molecular defects in at least one allele in 51 (98%) tumors.     

Association of a polymorphism of ABCB1 with obesity in Japanese individuals

The aim of the present study was to identify gene polymorphisms that confer susceptibility to obesity. A total of 5448 unrelated Japanese individuals from two independent populations were examined: subject panel A comprised 4252 individuals who visited participating hospitals; subject panel B comprised 1196 community-dwelling elderly individuals. The genotypes for 95 polymorphisms of 67 candidate genes were determined. The χ² test revealed that six polymorphisms were related (p < 0.05) to the prevalence of obesity in subject panel A; after application of Bonferroni's correction, however, only the 2677G → A/T polymorphism (rs2032582) of the ATP-binding cassette, subfamily B, member 1 gene (ABCB1) was significantly associated (p = 0.0003) with obesity. Subsequent multivariable logistic regression analysis also revealed that the 2677G → A/T polymorphism of ABCB1 was significantly associated with obesity. For validation of this association, the 2677G → A/T polymorphism of ABCB1 was examined in subject panel B and again found to be significantly associated with obesity. Body mass index was significantly (p = 0.01) greater for individuals with the variant T allele of this polymorphism than for those with the GG genotype in the combined subject panels A and B. Our results suggest that the ABCB1 genotype may prove informative for assessment of genetic risk for obesity in Japanese individuals.     

Staphylococcal cassette chromosome mec (SCCmec) characterization and panton-valentine leukocidin gene occurrence for methicillin-resistant Staphylococcus aureus in Turkey, from 2003 to 2006

Methicillin-resistant Staphylococcus aureus (MRSA) cause serious community-acquired and nosocomial diseases all over the world. We determined the SCCmec types and occurrence of the PVL gene by using TaqMan real-time PCR method, and correlated these with phenotypic antibiotic susceptibility patterns for MRSA strains collected from Gulhane Military Medical Academy Hospital (GMMAH) during 4 years study period. To our knowledge, this is the first report from Turkey of molecular SCCmec typing analysis of MRSA stains. A total of 385 clinical MRSA isolates collected in the clinical and Microbiology Laboratory at GMMAH between 2003 and 2006 were included in the study. Overall, SCCmec types-I, II, III, IV, V, nontypeable and PVL occurrence were detected in 11 (2.8%), 3 (0.8%), 316 (82.1%), 20 (5.1%), 20 (5.1%), 15 (3.9%) and 5 (1.3%) isolates, respectively. A total of 330 (85.5%) were SCCmec-I/II/III and 40 (10.3%) were SCCmec IV/V. SCCmec-I/II/III isolates were recovered more from patients with serious infections in surgical departments especially those with intensive care units than the SCCmec-IV/V isolates (χ² = 13.560, P < 0.001). SCCmec-I/II/III MRSA strains were predominantly recovered from blood stream (53.0%, P = 0.014), while SCCmec-IV/V strains were predominately isolated from skin and soft tissue and abscess (55.0%, P < 0.001). The PVL gene was detected in 10.0% of SCCmec-IV/V isolates in contrast to 0.3% in SCCmec-I/II/III (χ² = 25.164, P < 0.001). SCCmec-I/II/III MRSA strains were more resistant to clindamycin (χ² = 5.078, P = 0.024), amoxicillin-clavulanate (χ² = 84.912, P < 0.001), erythromycin (χ² = 4.651, P = 0.031), gentamicin (χ² = 24.869, P < 0.001), and rifampin (χ² = 18.878, P < 0.001) than SCCmec-IV/V MRSA strains. This data indicates that SCCmec-III MRSA strains that do not carry the PVL gene are the predominant MRSA strains in our hospital setting in Ankara, capital of Turkey and that SCCmec-I/II/III MRSA strains may cause serious infections in surgical departments especially those with intensive care units.     

Elevated frequency of an ETS-1 restriction fragment polymorphism in chronic B-cell leukaemia

We studied the frequency of an SstI polymorphism in 70 patients with chronic B-cell leukaemia (CLL) and 100 normal controls. There was a highly significant difference in the distribution of the three genotypes between the CLL patients and the normal controls (²= 13.46, 2 df, P<0.001). The C2 allele was found more frequently in CLL patients and may be a marker for a predisposition to develop CLL.     

Somatic mutagenesis in human lymphocytes depending on genotypes for detoxification and oxidative response loci

Associations of polymorphism of seven detoxification genes and three genes of oxidative response with the frequency of chromosome aberrations in human peripheral blood lymphocytes were studied. The genotyping data were correlated with the frequencies of spontaneous and γ-induced (1 Gy in vitro) chromosome aberrations estimated for a group of healthy donors (97 males under 25 years of age) by analyzing 500–1000 metaphase cells per individual. The spontaneous level of chromosome-type aberrations was reduced in homozygotes for the GSTM1 locus deletion, and especially in double homozygotes for deletions of the GSTM1 and GSTT1 genes. The frequency of γ-induced chromosome-type aberrations was reduced in G/G homozygotes for the minor allele of the poorly studied CYP1A1 T606G site: 0.094 ± 0.006 against 0.112 ± 0.002 for T allele carriers (P = 0.004). Linkage of the T606G site with well known and functionally important sites of the CYP1A1 gene (A4889G, T3801C) was analyzed.     

Flight of the honey bee VII: metabolic power versus flight speed relation

The existing experimental data on metabolic power P _m of honey bees are critically discussed, partly corrected for real flight conditions and plotted as a function of flight speed v. New wind tunnel measurements of tethered flight under near-natural conditions are added in the range 3.3<v<5.1 m·s^-1, derived from exhaustion flight measurements. Within this small sector the latter measurements can be characterised by a linear correlation: P _m(mW)=6.72v (m·s^-1)+13.83, the slope of which is significantly different from zero. The over-all P _m(v) curve is significantly not a straight line of zero slope but a U-shaped minimum curve and may be approximated by a second-order polynom: P _m=49.2-8.9v+1.5v ². The same is true for relative metabolic power, P _{m rel (e)} related to empty body mass of 76.5 mg: P _{m rel(e)}=630.0-114.0v+19.2v ² (P _m in mW: P _{m rel} in mW·g^-1; v in m·s^-1). The data support the existence of a U-shaped power-versus-speed curve in bees.Abbreviations bm body mass (mg) - f full - e empty - mu muscles - P _m (mJ·s^-1=mW) metabolic power (input) - P _{m rel} (mW·g^-1) relative metabolic power - P _mec (mW) mechanical power (output) - efficiency (of the flight musculature) - t(s) flight time - v (m·s^-1) relative speed between bee and air     

Analysis of caprine pituitary specific transcription factor-1 gene polymorphism in indigenous Chinese goats

Since mutations on POU1F1 gene possibly resulted in deficiency of GH, PRL, TSH and POU1F1, this study revealed the polymorphism of goat POU1F1-AluI locus and analyzed the distribution of alleles on 13 indigenous Chinese goat breeds. The PCR-RFLP analysis showed the predominance of TT genotype and the frequencies of allele T varied from 0.757 to 0.976 in the analyzed populations (SBWC, Bo, XH and HM). Further study, distributions of genotypic and allelic frequencies at this locus were found to be significantly different among populations based on a χ²-test (P < 0.001), suggesting that the breed factor significantly affected the molecular genetic character of POU1F1 gene. The genetic diversity analysis revealed that Chinese indigenous populations had a wide spectrum of genetic diversity in goat POU1F1-AluI locus. However, the ANOVA analysis revealed no significant differences for gene homozygosty, gene heterozygosty, effective allele numbers and PIC (polymorphism information content) among meat, dairy and cashmere utility types (P > 0.05), suggesting that goat utility types had no significant effect on the spectrum of genetic diversity. X. Y. Lan and M. J. Li equally contributed to this work.     

Mutagenic and Genotoxic Effects of <Emphasis Type="Italic">cis</Emphasis>-(Dichloro)tetraammineruthenium(III) Chloride on Human Peripheral Blood Lymphocytes

Chemotherapeutic agents play an important role in cancer treatment mostly due their systemic action on human organism allowing access to liquid tumors and even metastases. Among these drugs, ruthenium compounds have been showing promising results to treat tumors and represent an important development of new antitumor therapy. This study presents the evaluation of cis-(dichloro)tetraammineruthenium(III) chloride, cis-[RuCl₂(NH₃)₄]Cl, genotoxic effects using human peripheral blood lymphocytes cultured in vitro. Mitotic index (MI), chromosome aberrations (CA), and DNA damage using the comet assay were analyzed. MI in human peripheral blood lymphocyte cultures treated with 1, 10, 100, and 1,000 μg mL⁻¹ cis-[RuCl₂(NH₃)₄]Cl were 5.9%, 4.6%, 3.9%, and 0%, respectively. Doxorubicin chloridate was used as the positive control. CA derived from 1, 10, and 100 μg mL⁻¹ concentrations were defined as spontaneous when compared with the negative control, and at the concentration of 1,000 μg mL⁻¹, the cell cycle was inhibited (IM = 0%). Results obtained for the comet assay using cis-[RuCl₂(NH₃)₄]Cl suggest that this compound has no genotoxic activity against cultured human peripheral blood lymphocytes.