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Associations of transcript levels of oxidative stress-modifying genes SOD2, SOD3, NQO1 and NQO2 and their functional single nucleotide polymorphisms (SNPs) rs4880, rs1799895, rs2536512, rs699473, rs1800566 and rs1143684 with prognosis of breast cancer patients were studied. SNPs were assessed by allelic discrimination in a cohort of 321 breast cancer patients from the Czech Republic. Transcript levels were determined by real-time polymerase chain reaction (PCR) with absolute quantification in tumor and adjacent non-neoplastic control tissues. Both genotypes and transcript levels were then compared with available clinical data on patients. Patients carrying low activity allele Leu in NQO2 rs1143684 had a greater incidence of stage 0 or I disease (i.e., better prognosis) than patients with the Phe/Phe genotype. This association was more evident in patients without expression of progesterone receptors (p 5 0.031). Patients carrying the Thr allele in SOD3 rs2536512 SNP had a significantly greater incidence of tumors expressing estrogen receptors than patients carrying the Ala/Ala genotype (p 5 0.007). SOD3 transcript level was significantly higher in grade 1 or 2 tumors than in grade 3 tumors (p 5 0.006). Patients carrying T allele in SOD3 rs699473 SNP had significantly poorer progression-free survival (PFS) than patients carrying the CC genotype (p 5 0.038). The same applied to the subgroup of patients treated by hormonal regimens (p 5 0.021). Patients carrying the high activity Ala/Ala genotype in SOD2 (rs4880) had significantly poorer PFS than Val allele carriers in the group treated by cyclophosphamide but not hormonal regimens (p 5 0.004). Our results suggest that NQO2, SOD2 and SOD3 may significantly modify prognosis of breast cancer patients and that their significance should be further characterized.Breast cancer is the most common cancer in women. In 2008, about 1,383,523 new cases of invasive breast cancer were diagnosed worldwide. 1 The necessity of treating such a large number of patients calls for efficient tools that can be used for subgrouping patients according to estimated prognosis. A different spectrum of treatment modalities with diverse mechanisms of action and adverse effects could then be offered to various prognostic groups. Besides well-established classical prognostic factors such as tumor size, nodal status, grading and expression of hormonal receptors, numerous biological molecules are under investigation as potential prognostic biomarkers in breast carcinomas.Excess of oxidative stress, mediated by reactive oxygen species, may cause cellular deregulation leading to cell apoptosis, 2 proliferation or tumor promotion. 3 Alkylation and topoisomerase poisoning present the major mechanisms of action of cyclophosphamide and anthracyclines, respectively. Oxidative stress represents an additional cytotoxic mechanism. 4,5 One of the initial molecules of oxidative stress, superoxide anion radical, is formed by the univalent reduction of triplet-state molecular oxygen. This process is mediated by e...

Taxane and platinum-based chemotherapy regimens are standard treatment for advanced ovarian carcinoma. Expression levels of putative markers of taxane resistance in carcinoma tissues and paired peritoneal samples (n=55) and in 16 samples of ovaries without signs of carcinoma were compared with clinical data and the patients' time to progression. KIF14, PRC1, CIT and ABCC1 genes were significantly overexpressed in carcinomas when compared with normal ovarian tissues, while ABCB1 and CASP9 expression was decreased. Associations of protein expression of the proliferation marker Ki-67 with KIF14, PRC1, ABCB1 and CASP2 were found. Lastly, it was discovered that ABCB1 and CASP2 levels associated with FIGO stage and that the CIT level associated with the time to progression of ovarian carcinoma patients (P<0.0001). In conclusion, ABCB1, CASP2, KIF14, PRC1 and CIT genes seem to associate with surrogate markers of ovarian carcinoma progression and CIT gene associates with therapy outcome.

We aimed at determining whether any association exists between genetic polymorphisms in epoxide hydrolase (EPHX1), NADPH-quinone oxidoreductase (NQO1), glutathione S-transferases (GSTM1/P1/T1) and individual susceptibility to breast cancer. Polymerase chain reaction-restriction fragment length polymorphism-based genotyping assays were used to determine the frequency of polymorphisms in EPHX1 (exons 3 and 4), NQO1 (exon 6), GSTM1 (deletion), GSTP1 (exon 5), and GSTT1 (deletion) in a case -control study comprised of 238 patients with breast cancer and 313 healthy individuals. The distribution of genotypes in exon 6 of NQO1 was significantly different between the control group and breast cancer cases. Age-adjusted odds ratio (OR) for variant genotype NQO1*2/*2 was 3.68 (confidence interval (CI) ¼ 1.41 -9.62, P ¼ 0.008). Association of GSTP1*2/*2 genotype as well as that of low EPHX1 activity deduced by combinations of genotypes in exons 3 and 4 with breast cancer was suggestive, but nonsignificant. Individuals simultaneously lacking GSTM1 and carrying at least one GSTP1 variant allele were at significantly higher risk of breast cancer (OR ¼ 2.03, CI ¼ 1.18 -3.50, P ¼ 0.010). Combinations of either GSTM1null or GSTP1*2 with low activity of EPHX1 presented significant risk of breast cancer (OR ¼ 1.88, CI ¼ 1.00 -3.52, P ¼ 0.049 and OR ¼ 2.40, CI ¼ 1.15 -5.00, P ¼ 0.019, respectively) as well. In conclusion, the results suggest that genetic polymorphisms in biotransformation enzymes may play a significant role in the development of breast cancer.

A clinical course of patients with mantle cell lymphoma (MCL) is aggressive, and the disease is rarely curable. Proliferation rate is the most important prognostic factor. We developed a novel, reliable, rapid, and routinely applicable approach allowing a precise quantitative assessment of three proliferation markers, Ki-67, topoisomerase IIalpha, and TPX2. A total of 95 lymphoma specimens were measured in the study by real-time reverse transcription PCR (RQ-RT-PCR). We tested the reproducibility and accuracy of the assay and correlated the results with the immunohistochemical staining of the corresponding proteins. The results obtained indicated individual variability of the mRNA expression levels, reflecting heterogeneity of the proliferation rate in individual patients. In general, we observed the highest mRNA expression in the group of Burkitt lymphomas and the lowest in patients with reactive lymphadenopathies. We found increased proliferation rate in MCLs with high cyclin D1 mRNA, indicating a quantitative control of the cell cycle. We observed a correlation between mRNA expression level and the immunohistochemical staining of corresponding proteins, which significantly argues for the prognostic significance of the mRNA expression measuring. We confirmed the accuracy of the current assay for a precise quantitative examination of the proliferation activity. Real-time RT-PCR provides a novel approach applicable for clinical trials, and it represents a potent approach allowing to stratify MCL patients for entry into clinical trials according to the expression of the proliferation signature genes in their tumors. This approach may contribute to improved and individualized therapeutic options respecting the individual progression risk of patients with MCL.