Prognostic and predictable value of COX2 expression in Russian women with stage I breast cancer

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Background: Some previous studies found worse prognosis among cyclooxygenase-2 (COX2)-expressing breast cancers; we study prognostic and predictiable value of COX2 expression in breast cancer stage I. Methods: our study included Russian women with breast cancer stage I (n=315) treated in RCRC, RMAPE (1985-2009). A Tissue Micro Array (TMA) with triplicate 1 mm tumor tissue punches taken from tumor blocks was constructed in LUMC; sections were immunohistochemically stained for ER, PR, HER2-status, Ki67 (by standard morphological criteria); COX2-expression were evaluated as positive (>median; 31/309 cases, 10%) or negative (≤median; 278/209 cases, 90%). Also the histological type, grade, age and adjuvant endocrine therapy were examined. We analyzed the clinic and morphological data of COX2-positive tumors, prognostic value for survival (relapses free- RFS, overall- OS and cancer specific- CSS) and predictable value for endocrine therapy. Results: COX2-positive tumor were associated with ductal histological type (p=0,018), PR-negative status (p=0,027) and high Ki67 (p<0,0001), but not correlated (p>0,05) with age, grade, ER, HER2 status or biological subtype. In women with ER-negative tumors (104 patients, 34,1%) COX2-expression did not associate with worse survival (p>0,05). In contrast to this, in patients with ER-positive tumors (201 women, 65,9%) COX2-expression strongly correlated with worse RFS in univariate (HR 2,829, 95% CI 1,366-5,860, p=0,005) and multivariate analyses (HR=2,972, 95% CI 1,190-7,423, p=0,02). The same value of COX2-expression in women with ER-positive tumors was found for CSS (univariate: HR 3,421, 95% CI 1,436-8,149, p=0,005; multivariate: HR 4,260, 95% CI 1,344-13,504, p=0,014), but not for OS (p>0,05). In women who did not receive adjuvant endocrine therapy (145 patients, 46%) COX2 expression did not have any prognostic value for RFS, OS and CSS (p>0,05) but in patients that used adjuvant endocrine therapy (170 women, 54%) COX2-expression strongly associated with worse cancer-specific survival (HR 5,614 95% CI 1,165-27,059, p=0,032), but not with RFS and OS (p>0,05). Conclusions: COX2 expression plays a role in hormonal pathways and sensitivity for endocrine therapy.

Tumor suppressor activity of glucocorticoid receptor in the prostate

Glucocorticoids are extensively used in combination chemotherapy of advanced prostate cancer (PC). Little is known, however, about the status of the glucocorticoid receptor (GR) in PC. We evaluated over 200 prostate samples and determined that GR expression was strongly decreased or absent in 70-85% of PC. Similar to PC tumors, some PC cell lines, including LNCaP, also lack GR. To understand the role of GR, we reconstituted its expression in LNCaP cells using lentiviral approach. Treatment of LNCaP-GR cells with the glucocorticoids strongly inhibited proliferation in the monolayer cultures and blocked anchorage-independent growth. This was accompanied by upregulation of p21 and p27, down-regulation of cyclin D1 expression and c-Myc phosphorylation. Importantly, the activation of GR resulted in normalized expression of PC markers hepsin, AMACR, and maspin. On the signaling level, GR decreased expression and inhibited activity of the MAP-kinases (MAPKs) including p38, JNK/SAPK, Mek1/2 and Erk1/2. We also found that activation of GR inhibited activity of numerous transcription factors (TF) including AP-1, SRF, NF-kappaB, p53, ATF-2, CEBPalpha, Ets-1, Elk-1, STAT1 and others, many of which are regulated via MAPK cascade. The structural analysis of hepsin and AMACR promoters provided the mechanistic rationale for PC marker downregulation by glucocorticoids via inhibition of specific TFs. Our data suggest that GR functions as a tumor suppressor in prostate, and inhibits multiple signaling pathways and transcriptional factors involved in proliferation and transformation.

Effects of IKK inhibitor PS1145 on NF-κB function, proliferation, apoptosis and invasion activity in prostate carcinoma cells

A key antiapoptotic transcription factor, nuclear factor kappa-B (NF-kappaB), is known to be critically important for tumor cell growth, angiogenesis and development of metastatic lesions. We and others showed previously that NF-kappaB transcription factor was constitutively activated in androgen-independent prostate carcinoma (PC) cell lines due to the upregulated activity of inhibitor of NF-kappaB kinases (IKK). In this work, using luciferase assay, electrophoretic mobility shift assay and Northern blot analysis of expression of endogenous kappaB-responsive genes, we demonstrate that a novel highly specific small-molecule IKK inhibitor, PS1145, efficiently inhibited both basal and induced NF-kappaB activity in PC cells. We found that PS1145 induced caspase 3/7-dependent apoptosis in PC cells and significantly sensitized PC cells to apoptosis induced by tumor necrosis factor alpha. We also showed that PS1145 inhibited PC cell proliferation. Effects of PS1145 on proliferation and apoptosis correlated with inhibition of interleukin (IL)-6, cyclin D1, D2, inhibitor of apoptosis (IAP)-1 and IAP-2 gene expression and decreased IL-6 protein level. In addition, we found that incubation with PS1145 inhibited the invasion activity of highly invasive PC3-S cells in invasion chamber assay in a dose-dependent manner. Overall, this study provides the framework for development of a novel therapeutic approach targeting NF-kappaB transcription factor to treat advanced PC.

Neuroectodermal immunophenotype in uterine malignant mullerian tumors (MMT): comparative immunohistochemical analysis with embryonal uterine development

Multidirectional differentiation of neoplastic cells in uterine MMT is still a subject of controversy. The present study was designed to assess the immunophenotype of 15 uterine MMT paying special attention to the markers of neural (neuroendocrine) differentiation. In addition, the same immunohistochemical study was performed on 20 human fetal specimens in order to establish possible relationships between the immunophenotype of MMT and the expression of the corresponding antigens in the fetal tissues of the embryonal female genital tract. Besides the typical immunohistochemical patterns in three cases the epithelial component showed simultaneous coexpression of vimentin and desmin. EMA and cytokeratin, whereas epithelial markers were coexpressed with vimentin in the sarcomatous component of one adenosarcoma. Moreover, both components were immunoreactive to the markers of neural differentiation (PGP 9.5, GFAP, HNK-1, N-CAM, HBA71). This aberrant expression was not correlated with morphological signs of neural differentiation at either light microscopy or ultrastructural levels. Regarding the analysis of fetal tissues, both epithelial and mesenchymal elements in the fetal genital tract expressed the above-mentioned neural markers at different dates of gestation. The intensity of this expression diminishes as the fetus matures and at the end of antenatal life the immunophenotype characteristic for adult life is established. Taking into consideration the capacity of uterine tissue to reproduce embryonal phenotype during neoplastic transformation, we studied this abnormal immunoprofile and its hypothetic value for the diagnosis and prognosis of MMT.

Somatic genetic alterations (LOH) in benign, borderline and invasive ovarian tumours: intratumoral molecular heterogeneity

Loss of heterozygosity (LOH) affects a number of chromosome regions in ovarian cancer, pointing to the possible involvement of tumour-suppressor genes in ovarian tumorigenesis. We performed comparative analysis of allelic loss at 6 frequently affected chromosome regions in a panel of 53 benign, borderline and malignant ovarian tumours. Precursor lesions could provide evidence that an accumulation of genetic events is required for normal ovarian epithelium to generate malignant tumours. LOH on chromosome 1p was relatively common in benign, borderline and malignant tumours, while at 11p and 7q it was observed not only in invasive but also in borderline tumours. Moreover, 17q and 18q were affected mainly in advanced malignant tumours and revealed a high frequency of clonal intratumoral heterogeneity. We encountered different spectra of genetic alterations in primary tumours and their metastasis, which may be the results of intratumoral heterogeneity leading to dissemination in only some sub-clones.