Altered levels of plasma chemokines in breast cancer and their association with clinical and pathological characteristics.

Chemokines are a family of small, structurally related cytokines with chemoattractant and activation properties. In breast cancer, both epithelial cancer cells and cells within the microenvironment secrete chemokines with either tumor-promoting or anti-malignant potential. The equilibrium between these two chemokine activities plays a key role in the biology of the developing tumor, including its ability to metastasize. Here we evaluated the expression of chemokines in breast tumors and the plasma of breast cancer patients before treatment in order to identify a blood-based signature that could distinguish between malignant and non-malignant processes. We screened the mRNA expression of chemokine genes using cDNA microarray on homogenous, laser-capture microdissected breast cancer specimens. Further, using a protein array approach, we determined the levels of selected chemokines in the plasma of patients with breast cancer, benign breast tumors and healthy women. Finally, we analyzed the association between the levels of chemokines in breast and blood samples with the pathological characteristics of the disease. At mRNA level, 27 chemokines and 11 chemokine receptors were differentially expressed in cancers when compared with normal breast tissue. When compared to benign tumors, the only chemokine significantly upregulated in cancers was CXCL10. At protein level, with the exception of CXCL13, nine out of the ten selected chemokines (CCL2, CCL7, CCL18, CCL22, CXCL8, CXCL9, CXCL10, CXCL11 and osteoprotegerin) were significantly overexpressed in the plasma of breast cancers patients compared to healthy controls. After grouping, CXCL8, CXCL9 and CCL22 proved to be significant predictors for breast cancers as compared to healthy controls in a model of logistic regression. We found upregulation of CXCL8, CXCL11 and CXCL9 in triple negative carcinomas, CXCL9 in low proliferative carcinomas, and CXCL10, CCL7 and osteoprotegerin in poorly differentiated carcinomas. Furthermore, CXCL9 was overexpressed in lymph node negative tumors, whereas CXCL8 and CCL18 were higher in advanced stage carcinomas. We identified a panel of chemokines dysregulated in breast cancer that could be further investigated as prospective novel diagnostic markers or for therapeutic and prognostic applications.

Interaction between estrogens and androgen receptor genes microsatellites, prostate-specific antigen and androgen receptor expressions in breast cancer.

The role of estrogen and androgen receptors signaling in breast cancer is widely accepted, but the interrelations between them are not well understood. It was suggested that PSA could be a marker of endogenous balance between androgens and estrogens. In this context, we intended to investigate the potential of relationship between polymorphic tandem repeats (CAG, TA and CA) in AR (androgen receptor), ERalpha (estrogen receptor alpha) and ERbeta (estrogen receptor beta) genes and the immunoexpression of PSA and AR proteins. We assessed also the possible influences of CAG, TA, and CA variables and other available prognostic factors (ER, PR, AR, HER2/neu, PSA expression, and nodal status) on disease-free survival. We assessed the polymorphic tandem repeats lengths by genotyping, followed by high-resolution denaturing polyacrylamide gel electrophoresis in 163 breast cancers. Immunohistochemistry was performed to assess the expressions of AR, PSA, ER, PR and HER2/neu proteins. Our results showed that PSA was correlated with the length of CA repeats in the 3'-untranslated region of ERbeta, shorter CA repeats being correlated with PSA expression (p=0.03). AR immunoexpression was correlated with CAG repeats on AR gene, higher number of repeats being linked to a higher AR immunoexpression (p=0.04). Performing logistic regression to investigate relationships with prognosis, we observed that PSA immunoexpression (p=0.004), the nodal status (p-<0.001) and marginally, longer TA repeats (p=0.05) were correlated with increased disease-free survival. AR expression presented a low statistical value (p=0.054) in predicting evolution and was not entered into the multivariate regression analysis. Altogether, our findings supports the hypothesis that estrogens, through both alpha and beta-receptors variants are mediating the AR signaling pathway.

Estrogen receptor alpha polymorphisms: correlation with clinicopathological parameters in breast cancer.

Polymorphisms in estrogen receptor alpha gene (ESR1) have been previously associated with breast cancer risk; however, the results were not fully consistent. Our purpose was to study interactions between common genotypes in ESR1, breast cancer risk and tumor phenotypes. 6 ESR1 single nucleotide polymorphisms (SNPs) were genotyped in 103 breast cancer patients and 90 controls using hybridization probes; the genotypes were correlated with known prognostic factors for breast cancer and 5 years-follow up data. To assess estrogen and progesterone receptors (ER, PR) and HER2/neu expressions, immunohistochemistry was performed. Our results showed that rs3798577 was significantly associated with the risk of breast cancer, the common allele C conferring susceptibility (p-trend=4 x 10(-5)); rs3798577 was also correlated with PR expression (p=0.01), but not with ER expression; rs2228480 (p=0.047) and rs1801132 (p=0.02) were associated with the age at diagnosis; rs1801132 was correlated with hypercholesterolemia (p=0.003) and increased BMI (body mass index) (p=0.01); rs2234693 showed a low significant association (p=0.042) with the tumor grade; rs3798577 was correlated with disease-free survival (p=0.05), allele C conferring increased risk for relapses, but it reached not statistical significance after adjustments. In conclusions, we identified four genotypes significantly correlated with either the risk or some tumor characteristics, suggesting that the main selection criteria of the investigated SNPs (frequency and the position in modulating domains of the gene) are pertinent instruments for establish correlations between the gene structure and the tumor phenotype.

Prostate-specific antigen value as a marker in breast cancer.

The immunoexpression of prostate-specific antigen in breast cancers has been well established, but the role of this extra-prostate PSA appears to be a complex, poorly understood and of doubtful prognostic value. In this context, our aim was to evaluate PSA in breast carcinomas and to compare the results with several established prognostic markers of breast cancer: estrogen and progesterone receptors status, HER2/neu status, histological type of tumor, grade of differentiation, stage, tumor size, nodal and menopausal status. We have immunohistochemically assessed 53 breast carcinomas for PSA, ER, PR and oncoprotein HER2/neu status. The relationship between the clinical and histopathological markers was analyzed by chi-square test. In the present study PSA was expressed in 60.3% of cases, and we have found a significant correlation with the histological type and HER2/neu negative status in premenopausal women. No statistically significant difference was found between PSA positivity and menopausal status of the patients, nodal status, estrogen and progesterone receptors, HER2/neu status in postmenopausal patients, tumor size or histological grade. We conclude that in our study PSA can not be considered as a valuable independent prognostic factor in breast carcinoma. As long as the majorities of PSA positive carcinomas were small in size, early stage, better and moderately differentiated, HER2/neu negative and 70% of ER/PR positive carcinomas expressed PSA, it might be useful as a marker for a subset of breast cancers with better prognosis, which could respond to endocrine therapy, in correlation with other prognostic markers.