Prognostic molecular markers and neoadjuvant therapy response in anthracycline-treated breast cancer patients.

BACKGROUND: Identifying biomarkers that can predict the prognosis and treatment response is helpful for individualizing breast cancer (BC) therapy. A neoadjuvant treatment setting is ideal for testing biomarkers capable of predicting the treatment response. This study analyzed the value of immunohistochemical biomarkers for predicting pathological complete response (pCR) and prognosis in a group of BC patients receiving standardized treatment. PATIENTS AND METHODS: A total of 100 BC patients were treated with neoadjuvant chemotherapy (four cycles of epirubicin and cyclophosphamide) between 2000 and 2005. Formalin-fixed and paraffin-embedded core biopsies were taken before chemotherapy for immunohistochemical staining of ER, PgR, HER2, Bcl-2, p53, cyclin D1, CK5/6, CK8, CK18, and TOP2A. Patient and tumor characteristics and biomarker scores were used to predict pCR and prognosis, using logistic regression and Cox proportional hazard models. RESULTS: pCR was achieved in 11 patients and was predicted by the established marker Ki-67. In addition, CK5/6 and CK18 improved the prediction model and were associated with lower pCR rates. For the prognosis, only the established markers nodal status, Ki-67, and PgR predicted overall survival and nodal status; Ki-67 and PgR predicted distant disease-free survival. CONCLUSIONS: In this small retrospective study, CK5/6 and CK18 appeared to improve prediction of pCR in addition to the established markers. CK5/6 may indicate a tumor type resembling a basal phenotype that is more resistant to anthracycline-based therapy, and CK18 may indicate a luminal subtype that is more resistant to chemotherapy. However, these results need to be replicated in larger studies.

Proliferation and cell-cell fusion of endometrial carcinoma are induced by the human endogenous retroviral Syncytin-1 and regulated by TGF-beta.

Endometrial carcinomas (EnCa) predominantly represent a steroid hormone-driven tumor initiated from prestages. The human endogenous retrovirus HERV-W envelope gene Syncytin-1 was significantly increased at the mRNA and protein levels in EnCa and prestages compared to controls. Steroid hormone treatment of primary EnCa cells and cell lines induced Syncytin-1 due to a new HERV-W estrogen response element and resulted in increased proliferation. Activation of the cAMP-pathway also resulted in Syncytin-1 upregulation, but in contrast to proliferation, classic cell-cell fusions similar to placental syncytiotrophoblasts occurred. Cell-cell fusions were also histologically identified in endometrioid EnCa tumors in vivo. Clonogenic soft agar experiments showed that Syncytin-1 is also involved in anchorage-independent colony growth as well as in colony fusions depending on steroid hormones or cAMP-activation. The posttranscriptional silencing of Syncytin-1 gene expression and a concomitant functional block of induced cell proliferation and cell-cell fusion with siRNAs proved the essential role of Syncytin-1 in these cellular processes. TGF-beta1 and TGF-beta3 were identified as main regulative factors, due to the finding that steroid hormone inducible TGF-beta1 and TGF-beta3 inhibited cell-cell fusion, whereas antibody-mediated TGF-beta neutralization induced cell-cell fusions. These results showed that induced TGF-beta could override Syncytin-1-mediated cell-cell fusions. Interactions between Syncytin-1 and TGF-beta may contribute to the etiology of EnCa progression and also help to clarify the regulation of cell-cell fusions occurring in development and in other syncytial cell tumors.

Influence of mammographic density on the diagnostic accuracy of tumor size assessment and association with breast cancer tumor characteristics.

PURPOSE: The accuracy of breast cancer staging involves the estimation of the tumor size for the initial decision-making in the treatment. We investigated the accuracy of tumor size estimation and the association between tumor characteristics and breast density (BD). MATERIALS AND METHODS: A total of 434 women with a primary diagnosis of breast cancer were included in this prospective study at a specialist breast unit. Estimated tumor characteristics included tumor size, nodal status, estrogen/progesterone receptor status, Ki-67, HER2/neu, vascular invasion. Radiomorphological data included tumor size as assessed by mammography, breast ultrasonography, and clinical examination, and American College of Radiology (ACR) categories for BD. RESULTS: BD did not have a significant impact on the assessment of tumor size using breast ultrasound (deviation from ACR categories 1-4: 0.55-0.68 cm; P=0.331). The deviation in mammography was significantly different dependent on BD (0.42-0.9 cm; P<0.001). The clinical examination was not affected by BD. Age and tumor size were the only parameters associated with a denser breast in the multivariate analysis. Older women were less likely to have dense breasts (odds ratio 0.157 for women aged >or=70 years), and patients with larger tumors were less likely to have dense breasts (adjusted OR 0.36 for tumors>2 cm). CONCLUSION: Breast ultrasonography is more accurate than mammography for assessing tumor size in breasts with a higher BD. The difference in tumor size assessment needs to be taken into consideration in the design of clinical trials and treatment decisions.