Anna Maria Tokes

Identification of a claudin-4 and E-cadherin score to predict prognosis in breast cancer

The elevated expression of claudins (CLDN) and E‐cadherin (CDH‐1) was found to correlate with poor prognostic features. Our aim was to perform a comprehensive analysis to assess their potential to predict prognosis in breast cancer. The expression of CLDN‐1, ‐3–5, ‐7, ‐8, ‐10, ‐15, ‐18, and E‐cadherin at the mRNA level was evaluated in correlation with survival in datasets containing expression measurements of 1809 breast cancer patients. The breast cancer tissues of 197 patients were evaluated with tissue microarray technique and immunohistochemical method for CLDN‐1–5, ‐7, and E‐cadherin protein expression. An additional validation set of 387 patients was used to test the accuracy of the resulting prognostic score. Based on the bioinformatic screening of publicly‐available datasets, the metagene of CLDN‐3, ‐4, ‐7, and E‐cadherin was shown to have the most powerful predictive power in the survival analyses. An immunohistochemical protein profile consisting of CLDN‐2, ‐4, and E‐cadherin was able to predict outcome in the most effective manner in the training set. Combining the overlapping members of the above two methods resulted in the claudin‐4 and E‐cadherin score (CURIO), which was able to accurately predict relapse‐free survival in the validation cohort (P = 0.029). The multivariate analysis, including clinicopathological variables and the CURIO, showed that the latter kept its predictive power (P = 0.040). Furthermore, the CURIO was able to further refine prognosis, separating good versus poor prognosis subgroups in luminal A, luminal B, and triple‐negative breast cancer intrinsic subtypes. In breast cancer, the CURIO provides additional prognostic information besides the routinely utilized diagnostic approaches and factors. (Cancer Sci 2011; 102: 2248–2254)

β-catenin expression and claudin expression pattern as prognostic factors of prostatic cancer progression

To investigate the patterns of expression of the junctional proteins β‐catenin and claudins in different prognostic groups of patients with prostatic cancer, to determine their value as prognostic markers.

Stromal Matrix Protein Expression Following Preoperative Systemic Therapy in Breast Cancer

Purpose: Stromal alterations are observed following preoperative systemic therapy in breast cancer. The aim of the present study was to analyze the qualitative and quantitative changes of representative tumor stroma proteins in the context of neoadjuvant therapy and the response of patients undergoing preoperative systemic therapy. Experimental Design: Fifty women receiving preoperative systemic therapy were evaluated for clinical and pathologic parameters. Clinical response was defined according to International Union against Cancer (UICC) criteria, whereas pathologic responses to preoperative systemic therapy were defined according to the Chevallier and Sataloff classifications. The expression of tenascin-C, syndecan-1, collagen IV, and smooth muscle actin proteins was investigated using morphometric analysis of immunohistochemical reactions. Quantitative reverse transcription-PCR was done to evaluate the mRNA expression level of syndecan-1 and tenascin-C. The data were compared with 20 breast cancer samples of patients not treated with preoperative systemic therapy. Results: According to UICC criteria, the expression levels of collagen IV were up-regulated in all preoperative systemic therapy–treated patients (P = 0.002). Collagen IV was up-regulated in the preoperative systemic therapy group in both Chevallier and Sataloff classifications compared with the control cases (P = 0.025 and P = 001, respectively). There were no significant differences in the expression of smooth muscle actin between the treated and nontreated groups. The syndecan-1 proteoglycan level was significantly down-regulated in the preoperative systemic therapy group (Chevallier classes P = 0.015, Sataloff classes P = 0.015). Tenascin-C was up-regulated in women with progressive disease (P = 0.005). Conclusion: We have observed that the stromal component of breast carcinomas following preoperative systemic therapy differs from the nontreated tumors, which can be evaluated with the analysis of the above mentioned proteins.

Effect of ovariectomy and hormone replacement therapy on small artery biomechanics in angiotensin-induced hypertension in rats.

Objectives To test the effects of chronic angiotensin II administration on blood pressure and small artery biomechanics in the female sex hormone-depleted state (proposed to increase cardiovascular vulnerability) and with hormone replacement. Design Biomechanical properties of saphenous artery segments from ovariectomized (n = 10), ovariectomized + chronically angiotensin II infused-(n = 10), and ovariectomized + chronically angiotensin II-infused + sex hormone-replaced (n = 10) rats were studied. Methods Surgical ovariectomy was performed. Osmotic minipumps were used for chronic angiotensin II infusion (100 ng/min per kg). For hormone replacement therapy, oestradiol-propionate, 450 μg/kg for 7 days + medroxyprogesterone-acetate, 15 mg/kg for 14 days were given, intramuscularly. After 4 weeks, cylindrical segments of the saphenous artery were prepared and subjected to in-vitro microarteriographic measurements. Pressure – diameter curves (0–200 mmHg) were recorded in Krebs–Ringer solution, with smooth muscle contracted (norepinephrine, 16 μmol/l) and with relaxed (papaverine, 28 μmol/l). Results Chronic angiotensin II infusion significantly reduced the inner radius (at 100 mmHg: 298 ± 17 μm versus 347 ± 7 μm, P < 0.001), while wall-thickness did not change. Hormone replacement restored the morphological radius (333 ± 7 μm). Angiotensin II infusion slightly increased the full contraction range of the segments (defined as the percentage difference between fully contracted and fully relaxed diameters), which was further significantly increased by hormone replacement (39 ± 4%, 46 ± 8%, 62 ± 7% at 100 mmHg, in the three groups, respectively; P < 0.05). Despite unaltered stiffness in relaxed state, elastic moduli computed for the contracted segments decreased after hormone replacement. Conclusions These observations give further experimental support to the hypothesis that sex hormone replacement might be useful in preventing the development and/or stabilization of postmenopausal hypertension, as well as in treating existing disease.

Expression of proliferation markers Ki67, cyclin A, geminin and aurora-kinase A in primary breast carcinomas and corresponding distant metastases

Aims To assess the expression of the following cell cycle regulatory proteins in primary metastatic breast carcinomas (MBCs) and on availability in matched distant metastases (DMs): Ki67, cyclin A, geminin and aurora-kinase A (aurkA); and to compare the expression of these markers in early MBC (EMBC) and late MBC separated into groups according to median time point on metastatic event occurred (28 months). Methods The expression of the above mentioned markers was analysed in a total of 47 primary MBCs and 59 DMs (out of which 37 were pairs) by immunohistochemistry. Fourteen breast carcinomas with no relapse over a 10-year follow-up period were utilised as control cases (CBC). Results Among the MBCs, 22 metastasised to the bone, 4 to the lung and 21 to the central nervous system (CNS). Geminin (p<0.001) and Ki67 (p=0.001) were increased in the MBCs while aurkA and cyclin A showed no difference when compared with CBCs. There were no differences between aurkA, cyclin A and geminin expression in MBCs and DMs in general. Expression of Ki67 was, however, elevated (p=0.027) in DMs. In CNS metastases all markers showed elevated expression as compared to MBCs. In bone metastases, geminin was lower (p<0.001) compared with primary MBCs. In the metastases of the lung, the evaluated markers did not show different expression. According to the median follow-up until the metastatic event, Ki67 was found to be significantly elevated in EMBC (p=0.018). Conclusions Ki67 index and geminin distinguish a fraction of MBC with worse prognosis, showing increased levels in the latter in comparison to CBC being tumour-free over a 10-year follow-up period. Ki67 could possibly identify a group of MBCs that develop early DMs.

Reduced estradiol-induced vasodilation and poly-(ADP-ribose) polymerase (PARP) activity in the aortas of rats with experimental polycystic ovary syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder characterized by hyperandrogenism and insulin resistance, both of which have been connected to atherosclerosis. Indeed, an increased risk of clinical manifestations of arterial vascular diseases has been described in PCOS. On the other hand endothelial dysfunction can be detected early on, before atherosclerosis develops. Thus we assumed that vascular dysfunction is also related directly to the hormonal imbalance rather than to its metabolic consequences. To detect early functional changes, we applied a novel rodent model of PCOS: rats were either sham operated or hyperandrogenism was achieved by implanting subcutaneous pellets of dihydrotestosterone (DHT). After ten weeks, myograph measurements were performed on isolated aortic rings. Previously we described an increased contractility to norepinephrine (NE). Here we found a reduced immediate relaxation to estradiol treatment in pre-contracted aortic rings from hyperandrogenic rats. Although the administration of vitamin D3 along with DHT reduced responsiveness to NE, it did not restore relaxation to estradiol. Poly-(ADP-ribose) polymerase (PARP) activity was assessed by poly-ADP-ribose immunostaining. Increased PAR staining in ovaries and circulating leukocytes from DHT rats showed enhanced DNA damage, which was reduced by concomitant vitamin D3 treatment. Surprisingly, PAR staining was reduced in both the endothelium and vascular smooth muscle cells of the aorta rings from hyperandrogenic rats. Thus in the early phase of PCOS, vascular tone is already shifted towards vasoconstriction, characterized by reduced vasorelaxation and vascular dysfunction is concomitant with altered PARP activity. Based on our findings, PARP inhibitors might have a future perspective in restoring metabolic disorders in PCOS.

Endothelial relaxation mechanisms and nitrative stress are partly restored by Vitamin D3 therapy in a rat model of polycystic ovary syndrome

AIMS In polycystic ovary syndrome (PCOS), metabolic and cardiovascular dysfunction is related to hyperandrogenic status and insulin resistance, however, Vitamin D3 has a beneficial effect partly due to its anti-oxidant capacity. Nitrative stress is a major factor in the development of cardiovascular dysfunction and insulin resistance in various diseases. Our aim was to determine the effects of vitamin D3 in a rat model of PCOS, particularly the pathogenic role of nitrative stress. MAIN METHODS Female Wistar rats weighing 100-140g were administered vehicle (C), dihydrotestosterone (DHT) or dihydrotestosterone plus vitamin D3 (DHT+D) (n=10 per group). On the 10th week, acetylcholine (Ach) induced relaxation ability of the isolated thoracic aorta rings was determined. In order to examine the possible role of endothelial nitric oxide synthase (eNOS) and cyclooxygenase-2 (COX-2) pathways in the impaired endothelial function, immunohistochemical labeling of aortas with anti-eNOS and anti-COX-2 antibodies was performed. Leukocyte smears, aorta and ovary tissue sections were also immunostained with anti-nitrotyrosine antibody to determine nitrative stress. KEY FINDINGS Relaxation ability of aorta was reduced in group DHT, and vitamin D3 partly restored Ach induced relaxation. eNOS labeling was significantly lower in DHT rats compared to the other two groups, however COX-2 staining showed an increment. Nitrative stress showed a significant increase in response to dihydrotestosterone, while vitamin D3 treatment, in case of the ovaries, was able to reverse this effect. SIGNIFICANCE Nitrative stress may play a role in the pathogenesis of PCOS and in the development of the therapeutic effect of vitamin D3.

Effects of vitamin D3 derivative – calcitriol on pharmacological reactivity of aortic rings in a rodent PCOS model

BACKGROUND The aim of this study was to examine the effects of the hyperandrogenic state in dihydrotestosterone (DHT)-induced polycystic ovary syndrome (PCOS), the vascular responses to different vasoactive agents, and the modulatory role of vitamin D3. METHODS APCOS model was induced by DHT application in 20 female Wistar rats. Ten of the DHT treated rats simultaneously received calcitriol treatment. After 10 weeks, myographs were used to test the reactivity of isolated thoracic aortic rings to norepinephrine and acetylcholine. Thereafter, the vascular rings were incubated with the NO-synthase blocker (nitro-L-arginine methyl ester) or the cyclooxygenase inhibitor (indomethacin) for 20 min, and the effects of norepinephrine and acetylcholine were re-evaluated. RESULTS Norepinephrine-induced vasoconstriction was enhanced after DHT treatment, but this effect was attenuated by calcitriol administration. Vasorelaxation of DHT-treated thoracic aortic rings was impaired, but this could be partly reversed by calcitriol application. Impaired NO-dependent vasorelaxation in DHT-treated animals was mostly reversed by concomitant calcitriol administration, but this effect was diminished by prostanoid-dependent vasoconstriction. CONCLUSIONS These studies show that the enhanced sensitivity to vasoconstrictors and impaired NO-dependent vasorelaxation in hyperandrogenic PCOS rats could be partially reversed by calcitriol treatment.

Immunohistochemical phenotype of breast carcinomas predicts the effectiveness of primary systemic therapy

The purpose of the study was to identify breast cancer subtypes by immunohistochemistry likely to respond to neoadjuvant chemotherapy and to analyze the used chemotherapy regimen and the range of response rates. Analysis of a collected database was performed. Ninety-two patients were identified in our files who received neoadjuvant chemotherapy between 1998 and 2009. We used immunohistochemical profiles (ER, PgR, HER2, Ki-67 and p53) of NCB, FNAB and surgical breast specimens to subclassify the tumors. Pathological response rates were assessed following surgical removal of tumors by using the Chevallier classification. DFS and OS was measured in 88 cases from the date of definitive surgery to the date of last follow-up or death. Pathological complete or near-complete remission (pCR = Chevallier I and II) was observed in 13 of 92 cases (14.1%). According to the preoperative characteristics of the 13 tumors achieving pCR, 9 of the cases were triple negative, one of 13 was ER-/HER2+ and three of 13 ER+/HER2+. Twenty-four of 92 patients received taxane based neoadjuvant chemotherapy, 30 of 92 anthracycline based neoadjuvant chemotherapy, 33 of 92 taxane + anthracycline regimen and 2 of 92 CMF regimen. In the taxane treated group of patients the pCR rate was 29.1%, in the anthracycline group 6.6% and in the taxane + anthracycline treated group 12.1%. Concerning DFS, significant difference was observed between the Chevallier III and IV groups (p=0.006), and less events were observed in the pCR group (not significant). pCR was associated with significantly better OS (p=0.050). It seems that even limited, routinely used immunohistochemical profiling of tumors is able to predict the likelihood of pCR to neoadjuvant chemotherapy. Patients with triple negative and HER2-positive cancers are likely to achieve pCR after neoadjuvant chemotherapy.

Connexin 43 expression in rat aortic smooth muscle after ovariectomy and hormonal replacement.

The purpose of this study was to determine the effects of ovariectomy and long-term combined sexual hormone replacement on the gap junctional protein, connexin 43 (Cx43) of aortic medial smooth muscle cells in rats. Twenty non-pregnant mature Wistar female rats were divided into five groups (four animals in each group). Group A underwent ovariectomy, Group B underwent ovariectomy and received estradiol propionate, Group C underwent ovariectomy and received medroxyprogesterone acetate and Group D underwent ovariectomy and received both hormones. Group E was sham-operated and used as control. After 15 weeks of treatment, thoracic aortas were removed and immunohistochemistry was carried out using a specific fluorescent antibody against Cx43. Tissue sections were examined by confocal laser scanning microscopy and analysed by the Scion Image program. All five different groups had the same distribution and extent of Cx43 in the aorta. Neither the ovariectomy nor the hormone replacement had any effect on the Cx43 expression of aortic smooth muscle cells in rats as compared to control animals. These results indicate that sexual steroids do not influence the gap junctional protein Cx43 of the medial layer of aorta in rats. They may suggest that the beneficial effects of estrogen are not mediated via gap junctions in the human aorta either.