The introduction of microarray techniques to cancer research brought great expectations for finding biomarkers that would improve patients’ treatment; however, the results of such studies are poorly reproducible and critical analyses of these methods are rare. In this study, we examined global gene expression in 97 ovarian cancer samples. Also, validation of results by quantitative RT-PCR was performed on 30 additional ovarian cancer samples. We carried out a number of systematic analyses in relation to several defined clinicopathological features. The main goal of our study was to delineate the molecular background of ovarian cancer chemoresistance and find biomarkers suitable for prediction of patients’ prognosis. We found that histological tumor type was the major source of variability in genes expression, except for serous and undifferentiated tumors that showed nearly identical profiles. Analysis of clinical endpoints [tumor response to chemotherapy, overall survival, disease-free survival (DFS)] brought results that were not confirmed by validation either on the same group or on the independent group of patients. CLASP1 was the only gene that was found to be important for DFS in the independent group, whereas in the preceding experiments it showed associations with other clinical endpoints and with BRCA1 gene mutation; thus, it may be worthy of further testing. Our results confirm that histological tumor type may be a strong confounding factor and we conclude that gene expression studies of ovarian carcinomas should be performed on histologically homogeneous groups. Among the reasons of poor reproducibility of statistical results may be the fact that despite relatively large patients’ group, in some analyses one has to compare small and unequal classes of samples. In addition, arbitrarily performed division of samples into classes compared may not always reflect their true biological diversity. And finally, we think that clinical endpoints of the tumor probably depend on subtle changes in many and, possibly, alternative molecular pathways, and such changes may be difficult to demonstrate.

Tumor-associated macrophages (TAMs) play a significant role in at least two key processes underlying neoplastic progression: angiogenesis and immune surveillance. TAMs phenotypic changes play important role in tumor vessel abnormalization/ normalization. M2-like TAMs stimulate immunosuppression and formation of defective tumor blood vessels leading to tumor progression. In contrast M1-like TAMs trigger immune response and normalize irregular tumor vascular network which should sensitize cancer cells to chemo- and radiotherapy and lead to tumor growth regression. Here, we demonstrated that combination of endoglin-based DNA vaccine with interleukin 12 repolarizes TAMs from tumor growth-promoting M2-like phenotype to tumor growth-inhibiting M1-like phenotype. Combined therapy enhances tumor infiltration by CD4+, CD8+ lymphocytes and NK cells. Depletion of TAMs as well as CD8+ lymphocytes and NK cells, but not CD4+ lymphocytes, reduces the effect of combined therapy. Furthermore, combined therapy improves tumor vessel maturation, perfusion and reduces hypoxia. It caused that suboptimal doses of doxorubicin reduced the growth of tumors in mice treated with combined therapy. To summarize, combination of antiangiogenic drug and immunostimulatory agent repolarizes TAMs phenotype from M2-like (pro-tumor) into M1-like (anti-tumor) which affects the structure of tumor blood vessels, improves the effect of chemotherapy and leads to tumor growth regression.

The differences in patients’ response to the same medication, toxicity included, are one of the major problems in breast cancer treatment. Chemotherapy toxicity makes a significant clinical problem due to decreased quality of life, prolongation of treatment and reinforcement of negative emotions associated with therapy.In this study we evaluated the genetic and clinical risk factors of FAC chemotherapy-related toxicities in the group of 324 breast cancer patients. Selected genes and their polymorphisms were involved in FAC drugs transport (ABCB1, ABCC2, ABCG2,SLC22A16), metabolism (ALDH3A1, CBR1, CYP1B1, CYP2C19, DPYD, GSTM1, GSTP1, GSTT1, MTHFR,TYMS), DNA damage recognition, repair and cell cycle control (ATM, ERCC1, ERCC2, TP53, XRCC1).The multifactorial risk models that combine genetic risk modifiers and clinical characteristics were constructed for 12 toxic symptoms. The majority of toxicities was dependent on the modifications in components of more than one pathway of FAC drugs, while the impact level of clinical factors was comparable to the genetic ones. For the carriers of multiple high risk factors the chance of developing given symptom was significantly elevated which proved the factor-dosage effect. We found the strongest associations between concurrent presence of clinical factors - overall and recurrent anemia, nephrotoxicity and early nausea and genetic polymorphisms in genes responsible for DNA repair, drugs metabolism and transport pathways. These results indicate the possibility of selection of the patients with expected high tolerance to FAC treatment and consequently with high chance of chemotherapy completion without the dose reduction, treatment delays and decline in the quality of life.

The CRNDE gene seems to play an oncogenic role in cancers, though its exact function remains unknown. Here, we tried to assess its usefulness as a molecular prognostic marker in ovarian cancer. Based on results of our microarray studies, CRNDE transcripts were further analyzed by Real-Time qPCR-based profiling of their expression. The qPCR study was conducted with the use of personally designed TaqMan assays on 135 frozen tissue sections of ovarian carcinomas from patients treated with platinum compounds and either cyclophosphamide (PC, N = 32) or taxanes (TP, N = 103). Elevated levels of two different CRNDE transcripts were a negative prognostic factor; they increased the risk of death and recurrence in the group of patients treated with TP, but not PC (DNA-damaging agents only). Higher associations were found for overexpression of the short CRNDE splice variant (FJ466686): HR 6.072, 95% CI 1.814–20.32, p = 0.003 (the risk of death); HR 15.53, 95% CI 3.812–63.28, p < 0.001 (the risk of recurrence). Additionally, accumulation of the TP53 protein correlated with decreased expression of both CRNDE transcripts in tumor cells. Our results depict CRNDE as a potential marker of poor prognosis in women with ovarian carcinomas, and suggest that its significance depends on the therapeutic regimen used.

The purpose of our study was to establish the frequency and distribution of the four most common BRCA1 mutations in Polish general population and in a series of breast cancer patients. Analysis of the population frequency of 5382insC (c.5266dupC), 300T >G (p.181T >G), 185delAG (c.68_69delAG) and 3819del5 (c.3700_3704del5) mutations of the BRCA1 gene were performed on a group of respectively 16,849, 13,462, 12,485 and 3923 anonymous samples collected at birth in seven Polish provinces. The patient group consisted of 1845 consecutive female breast cancer cases. The most frequent BRCA1 mutation in the general population was 5382insC found in 29 out of 16,849 samples (0.17%). 300T >G and 3819del5 mutations were found in respectively 11 of 13,462 (0.08%) and four of 3923 (0.1%) samples. The population prevalence for combined Polish founder 5382insC and 300T >G mutations was 0.25% (1/400). The frequencies of 5382insC and 300T >G carriers among consecutive breast cancer cases were, respectively, 1.9% (35/1845) and 1.2% (18/1486). Comparing these data with the population frequency, we calculated the relative risk of breast cancer for 5382insC mutation at OR = 17 and for 300T >G mutation at OR = 26. Our results, based on large population studies, show high frequencies of founder 5382insC and 300T >G BRCA1 mutations in Polish general population. Carriage of one of these mutations is connected with a very high relative risk of breast cancer.

No abstract

Chromosomal instability is a known hallmark of many cancers. DNA polymerases represent a group of enzymes that are involved in the mechanism of chromosomal instability as they have a central function in DNA metabolism. We hypothesized that genetic variation in the polymerase genes may affect gene expression or protein configuration and by that cancer risk and clinical outcome. We selected four genes encoding for the catalytic subunits of the polymerases β, δ, θ and ζ (POLB, POLD1, POLQ and REV3L, respectively) and two associated proteins (MAD2L2 and REV1) because of their previously reported association with chromosomal instability and/or tumorigenesis. We selected potentially functional and most informative tagging single nucleotide polymorphisms (SNPs) for genotyping in a population-based series of 783 Swedish breast cancer (BC) cases and 1562 controls. SNPs that showed a significant association in the Swedish population were additionally genotyped in a Polish population consisting of 506 familial/early onset BC cases and 568 controls. SNPs in all three polymerase ζ subunit genes associated either with BC risk or prognosis. Two SNPs in REV3L and one SNP in MAD2L2 associated with BC risk: rs462779 (multiplicative model: OR 0.79, 95% CI 0.68-0.92), rs3204953 (dominant model: OR 1.28, 95% CI 1.05-1.56) and rs2233004 (recessive model: OR 0.49, 95% CI 0.28-0.86). Homozygous carriers of the minor allele C of the third SNP in REV3L, rs11153292, had significantly worse survival compared to the TT genotype carriers (HR 2.93, 95% CI 1.34-6.44). Minor allele carriers of two REV1 SNPs (rs6761391 and rs3792142) had significantly more often large tumours and tumours with high histological grade and stage. No association was observed for SNPs in POLB, POLQ and POLD1. Altogether, our data suggest a significant role of genetic variation in the polymerase ζ subunit genes regarding the development and progression of BC.

The 20q13 region is frequently amplified/overexpressed in breast tumours. However, the nature of this amplification/overexpression is unknown. Here, we investigated genetic variation in five 20q13 amplicon genes (MYBL2, AURKA, ZNF217, STK4 and PTPN1) and its impact on breast cancer (BC) susceptibility and clinical outcome. As a novel finding, four polymorphisms in STK4 (rs6017452, rs7271519) and AURKA (rs2273535, rs8173) associated with steroid hormone receptor status both in a Swedish population-based cohort of 783 BC cases and in a Polish familial/early onset cohort of 506 BC cases. In the joint analysis, the minor allele carriers of rs6017452 had more often hormone receptor positive tumours (OR 0.57, 95% CI 0.40-0.81), while homozygotes for the minor allele of rs7271519, rs2273535 and rs8173 had more often hormone receptor negative tumours (2.26, 1.30-3.39; 2.39, 1.14-5.01; 2.39, 1.19-4.80, respectively) than homozygotes for the common allele. BC-specific survival analysis of AURKA suggested that the Swedish carriers of the minor allele of rs16979877, rs2273535 and rs8173 might have a worse survival compared with the major homozygotes. The survival probabilities associated with the AURKA genotypes depended on the tumour phenotype. In the Swedish case-control study, associations with BC susceptibility were observed in a dominant model for three MYBL2 promoter polymorphisms (rs619289, P = 0.02; rs826943, P = 0.03 and rs826944, P = 0.02), two AURKA promoter polymorphisms (rs6064389, P = 0.04 and rs16979877, P = 0.02) and one 3'UTR polymorphism in ZNF217 (rs1056948, P = 0.01). In conclusion, our data confirmed the impact of the previously identified susceptibility locus and provided preliminary evidence for novel susceptibility variants in BC. We provided evidence for the first time that genetic variants at 20q13 may affect hormone receptor status in breast tumours and influence tumour aggressiveness and survival of the patients. Future studies are needed to confirm the prognostic value of our findings in the clinic.