C-X-C ligand 10 and C-X-C receptor 3 status can predict tamoxifen treatment response in breast cancer patients.

To investigate the expression levels of CXCL10 and CXCR3 in tumors from breast cancer patients randomized to adjuvant tamoxifen treatment or no endocrine treatment, in order to further study the connection to prognosis and prediction of tamoxifen treatment outcome. Immunohistochemistry on tissue microarrays from 912 breast cancer patients randomized to tamoxifen or no endocrine treatment. CXCR3 status was found to be a prognostic tool in predicting distant recurrence, as well as reduced breast cancer-specific survival. In patients with estrogen receptor (ER)-positive tumors, tumors with strong CXCL10 levels had improved effect of tamoxifen treatment in terms of local recurrence-free survival [risk ratio (RR) 0.46 (95 % CI 0.25-0.85, P = 0.01)] compared with patients with tumors expressing weak CXCL10 expression. Further, patients with ER-positive tumors with strong CXCR3 expression had an improved effect of tamoxifen in terms of breast cancer-specific survival [RR 0.34 (95 % CI 0.19-0.62, P < 0.001)] compared with the group with weak CXCR3 levels [RR 1.33 (95 % CI 0.38-4.79, P = 0.65)]. We show here for the first time that CXCL10 and CXCR3 expression are both predictors of favorable outcome in patients treated with tamoxifen.

17ß-Hydroxysteroid dehydrogenase type 14 is a predictive marker for tamoxifen response in oestrogen receptor positive breast cancer.

INTRODUCTION: 17ß-Hydroxysteroid dehydrogenases (17ßHSDs) are important enzymes regulating the pool of bioactive steroids in the breast. The current study was undertaken in order to evaluate implications of 17ßHSD14 in breast cancer, measuring 17ßHSD14 protein expression in breast tumours. METHODS: An antibody targeting the 17ßHSD14 antigen was generated and validated using HSD17B14-transfected cells and a peptide-neutralising assay. Tissue microarrays with tumours from 912 post-menopausal women diagnosed with lymph node-negative breast cancer, and randomised to adjuvant tamoxifen or no endocrine treatment, were analysed for 17ßHSD14 protein expression with immunohistochemistry. RESULTS: Results were obtained from 847 tumours. Patients with oestrogen positive tumours with high 17ßHSD14 expression had fewer local recurrences when treated with tamoxifen (HR 0.38; 95% C.I. 0.19-0.77, p = 0.007) compared to patients with lower tumoural 17ßHSD14 expression, for whom tamoxifen did not reduce the number of local recurrences (HR 1.19; 95% C.I. 0.54-2.59; p = 0.66). No prognostic importance of 17ßHSD14 was seen for systemically untreated patients. CONCLUSIONS: Using a highly specific validated antibody for immunohistochemical analysis of a large number of breast tumours, we have shown that tumoural expression levels of 17ßHSD14 can predict the outcome of adjuvant tamoxifen treatment in terms of local recurrence-free survival in patients with lymph node-negative ER+ breast cancer. The results need be verified to confirm any clinical relevance.

Progesterone and levonorgestrel regulate expression of 17ßHSD-enzymes in progesterone receptor positive breast cancer cell line T47D.

The use of combined hormone replacement therapy (HRT) with oestrogens and progestins in postmenopausal women has been associated with an increased risk for developing breast cancer. The reasons are not fully understood, but influence of HRT on endogenous conversion of female sex hormones may be involved. The expression of 17ß hydroxysteroid dehydrogenases (17ßHSD), which are enzymes catalysing the conversion between more or less potent oestrogens, may partly be regulated by progestins. The breast cancer cell lines T47D, MCF7 and ZR75-1 were treated with progesterone, medroxyprogesterone acetate (MPA) or levonorgestrel for 48 and 72 h at 10(-7) and 10(-9)M to investigate influence on 17ßHSD1, 17ßHSD2 and 17ßHSD5 mRNA expression measured by real time PCR. The expression of 17ßHSD1 increased in progesterone and levonorgestrel treated T47D cells (48 h 10(-7)M P=0.002; P<0.001) and 17ßHSD5 increased after progesterone treatment (48 h 10(-7)M P=0.003), whereas the expression of 17ßHSD2 decreased after the (48 h 10(-7)M P=0.003; P<0.001). Similar, but less prominent effects were seen in MCF7 and ZR75-1. The progestin effects on 17ßHSD-expression were lost when T47D cells were co-treated with progestins and the progesterone receptor (PgR) inhibitor mifprestone. We show that both reductive (17ßHSD1 and 17ßHSD5) and oxidative (17ßHSD2) members of the 17ßHSD-family are under control of progesterone and progestins in breast cancer cell lines. This is most clear in T47D cells which have high PgR expression. 17ßHSD-enzymes are important players in the regulation of sex steroids locally in breast tumours and tumoural expression of various 17ßHSD-enzymes have prognostic and treatment predictive relevance. We propose a mechanism for increased breast cancer risk after HRT in which hormone replacement affects the expression of 17ßHSD-enzymes, favouring the expression of reductive enzymes, which in turn could increase levels of bioactive and mitogenic estrogens in local tissue, e.g. breast tissue.

A validated and rapid high-performance liquid chromatography method for the quantification of conversion of radio-labelled sex steroids.

The 17ß-hydroxysteroid dehydrogenase enzymes modify the availability of potent sex steroids and have thus attracted interest in the study of several steroid-dependent pathologies including breast, endometrial and prostate cancers. An increased awareness of the importance of steroidogenic enzymes has brought forth a demand for efficient assays to study the effects of individual enzymes on steroid levels. Methods used for assessing steroid conversion are often laborious and frequently involve hazardous sample preparation steps. We developed and validated an optimised simple method for sample preparation of sex steroids using protein precipitation by the addition of zinc sulphate/sodium hydroxide. The interconversion of radio-labelled oestrogens and androgens was quantified using high-performance liquid chromatography separation of oestrone, oestradiol, androstenedione and testosterone followed by online radiometric flow scintillation analysis. The method, which can be applied for assessing, e.g., the efficacy of inhibitors of steroidogenic enzymes, was successfully used for evaluating oestrogenic interconversion in breast cancer cell lines MCF7 and T-47D.

17beta-hydroxysteroid dehydrogenase 14 affects estradiol levels in breast cancer cells and is a prognostic marker in estrogen receptor-positive breast cancer.

Estrogens have an important role in the progression of breast cancer. The 17beta-hydroxysteroid dehydrogenase (17HSD) family has been identified to be of significance in hormone-dependent tissues. 17HSD1 and 17HSD2 are the main 17HSD enzymes involved in breast cancer investigated this far, but it is possible that other hormone-regulating enzymes have a similar role. 17HSD5 and 17HSD12 are associated with sex steroid metabolism, and 17HSD14 is a newly discovered enzyme that may be involved in the estrogen balance. The mRNA expression of 17HSD5, 17HSD12, and 17HSD14 were analyzed in 131 breast cancer specimens by semiquantitative real-time PCR. The results were compared with recurrence-free survival and breast cancer-specific survival of the patients. The breast cancer cell lines MCF7, SKBR3, and ZR75-1 were transiently transfected with 17HSD14 to investigate any possible effect on estradiol levels. We found that high 17HSD5 was related to significantly higher risk of late relapse in estrogen receptor (ER)-positive patients remaining recurrence-free later than 5 years after diagnosis (P = 0.02). No relation to 17HSD12 expression was found, indicating that 17HSD12 is of minor importance in breast cancer. Patients with ER-positive tumors with high expression levels of 17HSD14 showed a significantly better prognosis about recurrence-free survival (P = 0.008) as well as breast cancer-specific survival (P = 0.01), confirmed by multivariate analysis (P = 0.04). Transfection of 17HSD14 in the human breast cancer cells MCF7 and SKBR3 significantly decreased the levels of estradiol, presenting an effect of high expression levels of the enzyme.