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Beta-catenin accumulation is suppressed by TGF-beta1 (transforming growth factor beta1) in intestinal epithelium suggesting negative feedback between these two factors. Besides that, beta-catenin interacts with HIF-1alpha (hypoxia-inducible factor-1alpha) at the promoter region of HIF-1 target genes. Our study was aimed at comparison of beta-catenin with HIF-1alpha, TGF-beta1, Ki67 and survival of sporadic colorectal cancer patients. Expressions of beta-catenin, TGF-beta1, HIF-1alpha, Ki67 were evaluated in triads of specimens of each primary tumor of 72 sporadic colorectal cancers with immunohistochemistry due to limited availability of tissue material. Disease-free survival was analyzed in case of all 100 beta-catenin stained tumors, in 85 cancers stained for HIF-1 and in 72 neoplasms with TGFbeta1 staining. Beta-catenin, TGF-beta1 and HIF-1alpha accumulated in 72 colorectal cancer cells. Beta-catenin correlated both with HIF-1alpha and TGF-beta1 in all colorectal cancers (p < 0.009, r = 0.307 and p = 0.003, r = 0.342, respectively) and in subgroups of different clinico-pathological profile. Beta-catenin failed to correlate with Ki67. In case of beta-catenin, TGF-beta1 and HIF-1alpha, disease-free survival curves failed to show any statistically significant differences between groups of marker negative tumors, cancers with low expression and neoplasms with higher protein expression. Positive correlations between beta-catenin and TGF-beta1 may indicate ineffective attempts of TGF-beta1 to reduce intracellular level of beta-catenin in colorectal cancer. Associations between beta-catenin and HIF-1alpha reflect previously detected interactions between HIF-1alpha with beta-catenin and are confirmative for presence of such reactions in human colorectal cancer.

Background: Tumor hypoxia is marked by enhanced expression of hypoxia-inducible factor-alpha (HIF-1alpha) and glucose transporter-1 (Glut-1). Hypoxic conditions have also been associated with overexpression of angiogenic factors, such as leptin. The aim of our study was to analyze the relationships between hypoxia markers HIF-1alpha, Glut-1, leptin, leptin receptor (ObR) and other breast cancer biomarkers in primary and metastatic breast cancer in patients treated or untreated with preoperative chemotherapy., Methods: The expression of different biomarkers was examined by immunohistochemistry in 116 primary breast cancers and 65 lymph node metastases. Forty five of these samples were obtained form patients who received preoperative chemotherapy and 71 from untreated patients., Results: In primary tumors without preoperative chemotherapy, HIF-1alpha and Glut-1 were positively correlated (p = 0.02, r = 0.437). HIF-1alpha in primary and metastatic tumors without preoperative therapy positively correlated with leptin (p < 0.0001, r = 0.532; p = 0.013, r = 0.533, respectively) and ObR (p = 0.002, r = 0.319; p = 0.083, r = 0.387, respectively). Hypoxia markers HIF-1alpha and Glut-1 were negatively associated with estrogen receptor alpha (ERalpha) and positively correlated with estrogen receptor beta (ERbeta). In this group of tumors, a positive correlation between Glut-1 and proliferation marker Ki-67 (p = 0.017, r = 0.433) was noted. The associations between HIF-1alpha and Glut-1, HIF-1alpha and leptin, HIF-1alpha and ERalpha as well as Glut-1 and ERbeta were lost following preoperative chemotherapy., Conclusions: Intratumoral hypoxia in breast cancer is marked by coordinated expression of such markers as HIF-1alpha, Glut-1, leptin and ObR. The relationships among these proteins can be altered by preoperative chemotherapy.

It was shown the functional crosstalk between ERRalpha and ERalpha in breast cancer, however, the biological significance of estrogen-related receptor alpha (ERRalpha) remains largely unclear. Therefore, we examined the expression of ERRalpha in 39 primary human breast cancer tissues and 19 matched normal tissues using RT-PCR and immunohistochemistry in the context of the aromatase, ERalpha and proliferation markers (c-myc, Ki-67) expression. Compared to the normal breast tissue, breast cancer tissues showed a slightly higher expression level of ERRalpha mRNA (mean 46.2+/-S.D.42.0, 57.7+/-S.D.58.7, respectively). However, ERRalpha mRNA levels in breast cancer tissues showed greater diversity than in normal tissues. Immunohistochemical analysis of breast cancers revealed perinuclear and cytoplasmic localization of ERRalpha. Our study shows that there is no correlation between ERRalpha and ERalpha expression. We demonstrated a positive correlation between ERRalpha and c-myc at the transcriptional level and statistically significant positive correlation between aromatase and the ERRalpha at protein level. It seems that ERRalpha could play an important role in the alternative pathway to classical estrogen receptors-dependent pathway in cell signaling. Development and use of ERRs modulators might lead in the future to design new well-tolerated and individualized therapeutic agents.

Background: Insulin-like growth factor-I (IGF-I) and vascular endothelial growth factor (VEGF) belong to a group of hypoxia related proteins. IGF-I induces expression of VEGF and decomposes wild type p53 in cancer cell lines. The goal of our study was to evaluate serum IGF-I, VEGF and p53 with respect to overall and disease free survival of patients with colorectal cancer (CRC) patients compared with healthy volunteers., Methods: Preoperative blood samples from 125 patients with CRC and 16 healthy volunteers were examined using ELISA for serum IGF-I, p53 and VEGF concentrations., Results: Concentrations of p53 and VEGF were significantly higher in CRC patients than in controls (p<0.0006 and p<0.0001, respectively). IGF-I was not statistically different between both groups. Serum IGF-I showed negative correlation with p53 in CRC patients (p<0.04, r=-0.193). IGF-I and VEGF showed negative correlation in poorly differentiated cancers (G3) (p<0.03, r=-0.339). Patients with VEGF concentrations that were above average for the cancer population survived for a shorter period of time (p=0.065 in evaluation of overall survival and 0.071 in estimation of disease-free survival during a 3-year follow-up) compared with patients with serum VEGF lower than the highest values seen in controls., Conclusions: Comparisons between serum IGF-I and p53 appear to confirm the metabolism of p53 by IGF-I. Serum VEGF showed prognostic significance in our study. Serum concentrations of IGF-I and VEGF did not show positive correlation, as expected due to IGF-I induction of VEGF in malignant colon cell lines.

Leptin and its receptor may be engaged in pathogenesis of breast cancer among various human tumors. In vitro investigations showed leptin-mediated escalation of estrogen synthesis and boosted activity of estrogen receptor ERalpha. Furthermore, leptin induced growth of malignant cells, counteracted apoptosis and stimulated cell migration as well as overexpression of angiogenic factors and degrading enzymes that split network of intercellular matrix. On the other side, leptin has been reported to favor apoptosis, lately. Proapoptotic effect of leptin action was revealed in interstitial cells of bone marrow and adipocytes. Our past reports provide evidences for overexpression of leptin and its receptor in breast cancer in comparison with benign mammary lesions. In current study we aimed at assessment of eventual relationships between leptin, leptin receptor and selected protein regulators of apoptosis in breast cancer. We applied immunohistochemistry for leptin, leptin receptor, anti-apoptotic Bcl-2 and Bcl-xL as well as pro-apoptotic Bak and Bax expression assessment in 106 cases of human breast cancers. The immunoreaction was graded and statistically evaluated. Expression of leptin was positively correlated with Bcl-xL, Bak and Bax (p<0.001, r=0.614; p<0.001, r=0.518; p<0.001, r=0.511, respectively). Statistical significances were noted between expression of leptin receptor and Bcl-xL or Bax (p=0.011, r=0.210; p<0.001, r=0.313, respectively). No correlation was encountered between leptin and Bcl-2, either leptin receptor and Bcl-2 or leptin receptor and Bak. On the basis of obtained results, leptin system could interfere in balance among expressions of pro- and anti-apoptotic proteins and regulate cell turnover and--by means of it--facilitate breast cancer progression.

Gap junctions are specialized cell membrane channels composed of connexins (Cxs), which mediate the direct passage of small molecules between adjacent cells. They are involved in the regulation of cell cycle, cell signaling and differentiation as well as probably invasion and metastasis. Up to now, Cx32 status in human breast cancer has not been studied. Consequently, the aim of the present study was the evaluation of the expression of connexin 32 (Cx32) in primary breast tumors (PTs) and matched-paired metastases to lymph nodes (MLNs) in correlation with selected clinicopathological features. Tissue samples from 79 women were examined by immunohistochemistry, using the streptavidin-biotin-peroxidase complex technique for Cx32. Cytoplasmic expression of Cx32 was detected in 31 of 79 breast cancers (39.2%). Both epithelial and myoepithelial cells of normal ducts adjacent to the tumor did not express Cx32. Increased expression of studied Cx was observed in metastases to lymph nodes relative to primary tumors. Additionally, Cx32-negative primary tumors developed Cx32-positive metastases. Statistical comparisons of Cx32 expression in the matched pairs indicate that this protein significantly increased in lymph node metastases compared to primary tumors (p<0.001). The expression of Cx32 in primary breast cancer was not statistically associated with age of patients, tumor size, lymph node status, but we observed a tendency toward association between Cx32 expression and histological differentiation. In conclusion, transformed cells may have an ability to produce Cxs also atypical for normal cells. Increased expression of Cx32 in metastases to the lymph nodes might reflect alteration in connexin gene transcription during breast carcinogenesis and finally, it may be a sign of more malignant phenotype of cancerous cells.

Purpose: Recent in vitro studies suggested that the autocrine leptin loop might contribute to breast cancer development by enhancing cell growth and survival. To evaluate whether the leptin system could become a target in breast cancer therapy, we examined the expression of leptin and its receptor (ObR) in primary and metastatic breast cancer and noncancer mammary epithelium. We also studied whether the expression of leptin/ObR in breast cancer can be induced by obesity-related stimuli, such as elevated levels of insulin, insulin-like growth factor-I (IGF-I), estradiol, or hypoxic conditions., Experimental Design: The expression of leptin and ObR was examined by immunohistochemistry in 148 primary breast cancers and 66 breast cancer metastases as well as in 90 benign mammary lesions. The effects of insulin, IGF-I, estradiol, and hypoxia on leptin and ObR mRNA expression were assessed by reverse transcription-PCR in MCF-7 and MDA-MB-231 breast cancer cell lines., Results: Leptin and ObR were significantly overexpressed in primary and metastatic breast cancer relative to noncancer tissues. In primary tumors, leptin positively correlated with ObR, and both biomarkers were most abundant in G3 tumors. The expression of leptin mRNA was enhanced by insulin and hypoxia in MCF-7 and MDA-MB-231 cells, whereas IGF-I and estradiol stimulated leptin mRNA only in MCF-7 cells. ObR mRNA was induced by insulin, IGF-I, and estradiol in MCF-7 cells and by insulin and hypoxia in MDA-MB-231 cells., Conclusions: Leptin and ObR are overexpressed in breast cancer, possibly due to hypoxia and/or overexposure of cells to insulin, IGF-I, and/or estradiol.

Aims and Background: Vascular endothelial cadherin (VE-cadherin) preserves the tightness of the mature vascular network as a component of endothelial adherens junctions. Vascular endothelial growth factor (VEGF) makes VE-cadherin dissociate from complexes with beta-catenin, so that endothelial cells can loosely proliferate and migrate. We searched for relationships between VEGF and VE-cadherin levels in preoperative sera of patients with colorectal cancer (CRC). We also compared VE-cadherin levels of control and preoperative CRC sera in relation to clinicopathological features., Methods: We measured with an ELISA kit the serum levels of the proteins in preoperative samples from 125 CRC patients and in samples from 16 healthy volunteers., Results: Serum VE-cadherin was about fourfold higher in CRC patients than in controls (P < 0.00001), with similar results being found in subgroups with different clinicopathological features versus controls. VE-cadherin was not correlated with VEGF in the entire group of CRC patients nor in the subgroups of node-positive and node-negative patients, different grades of histological differentiation (G2 or G3), extent of tumor growth (pT1+pT2 or pT3+pT4), histopathological type (adenocarcinoma or mucinous carcinoma), sex, age, and tumor site (colon or rectum). However, the serum levels of VE-cadherin and VEGF in CRC patients, which were higher than the mean values of controls, tended towards a negative correlation in node-positive patients (P = 0.078, r = -0.279)., Conclusions: VEGF and VE-cadherin seem to be independent markers of angiogenesis in CRC with no significant correlation between their serum levels.

Diversity of P53 impact on tumor angiogenesis is due to the fact that wild-type P53 decreases expression of vascular endothelial growth factor (VEGF), but mutant P53 upregulates it. Therefore, we aimed at uncovering relations between preoperative serum levels of VEGF and P53 in colorectal cancer (CRC) patients. Preoperative blood samples of 125 CRC patients and 16 control healthy volunteers were examined with an ELISA-kit for serum P53 levels and VEGF. P53 did not correlate with VEGF in the whole group of CRC patients. However, P53 associated with VEGF in case of colorectal cancer patients, whose serum values of VEGF were higher than in controls (VEGF{H} >5.9333 pg/ml) (r=0.274, p<0.009). We revealed a positive correlation between P53 and VEGF{H} in subsets of poorly differentiated (G3) cancers (p<0.02), lymph node positive (p<0.007), pT3 or pT4 patients (p<0.004) without analogous relation in moderately differentiated (G2) tumors, node negative patients or pT1 or pT2 patients. P53 and IGF-I negatively correlated in all CRC patients (p<0.04) and VEGF{H} individuals of pT3 or pT4 (p<0.05) without any significant linkage in tumors of pT1 or pT2. The positive correlation between serum P53 and VEGF points at mutation of P53 and is a highly probable sign of poor prognosis in colorectal cancer. For now it can not be excluded that the binary analysis of serum P53 and VEGF could help select CRC patients endangered by rapid growth and lymph node metastases.

Apoptosis is a process associated with development and progression of breast cancer. The association between connexins and programmed cell death has only been demonstrated in a few studies. The aim of the present study was the evaluation of Cx26 and Cx43 expression in breast cancer in correlation with Bcl-2 and Bak proteins as well as with selected clinicopathological features. Tissue samples from 71 women were examined by immunohistochemistry, using the streptavidin-biotin-peroxidase complex technique for Cx26, Cx43, Bak and Bcl-2. Cytoplasmic expression of Cx26 and Cx43 was detected in 34 (47.9%) and 61 (85.9%) of breast cancers, respectively. Bcl-2 and Bak expression was found in 59 (83%) and 50 (70%) of studied cases, respectively. We found a positive correlation between Cx26 and Bak expression (r=0.541, p<0.0001) as well as between Cx43 and Bak (r=0.589, p<0.0001), but not between the studied connexins and Bcl-2. The expression of Cx26 was not associated with age, tumor size, lymph node status or histological grade. However, we observed an association between Cx43 expression and histological grade G3 (p<0.04). Cytoplasmic localization of evaluated connexins supports the concept of alterations in connexins expression in breast cancer cells. The associations of evaluated connexins with Bak protein could suggest that connexins localized in the cytoplasm may participate in signaling apoptotic pathways.

Disturbance in expression of estrogen receptors together with changing influence of growth factor receptors and apoptosis associated proteins plays a role in breast cancer development and progression. However, immunohistochemical detection and relationships among these proteins were not often considered in relation to breast cancer and a few evaluations of expression provided mismatching results and conclusions. Consequently, we examined by immunohistochemistry the expression of the insulin-like growth factor-I receptor (IGF-IR), estrogen receptor alpha (ERalpha) and apoptosis-associated proteins, Bcl-2 and Bax, in human primary breast cancer, as well as analyzing the relationships among these proteins. The positive immunostaining for IGF-IR, ERalpha, Bcl-2 and Bax was noted in 56, 63.8, 82.8 and 50% of tumors, respectively. We observed that IGF-IR negatively correlated with ERalpha in the group of all tumors and in axillary node negative cancer (p<0.03, p<0.05, respectively), but not in the subgroup of node positive cancer. Expression of ERalpha correlated positively with Bcl-2 and negatively with Bax proteins (p<0.0001, p<0.05, respectively). We did not note significant relationships between IGF-IR and Bcl-2, or IGF-IR and Bax proteins. We found that increased Bax expression was associated with positive lymph node status, pT2 stage and G3 grade of tumors. Knowledge about alterations in the IGF-IR expression and relations of the receptor to other biological factors could help in our understanding of breast cancer biology and the importance of the IGF-IR in cancer progression as well as in effective management of breast cancer.

In our previous investigation Insulin Receptor Substrate 1 (IRS-1) correlated with proliferation marker Ki-67 in human breast cancer. The aim of the present study was to assess relationships between IRS-1 expression and anti-apoptotic Bcl-xL as well as proapoptotic Bax proteins, assessed by immunohistochemistry, in primary tumors and lymph node metastases of breast cancer. IRS-1 is positively associated with both Bcl-xL and Bax in primary and metastatic tumors. Thus, our results could suggest that IRS-1 might affect turnover of cancer cells and breast cancer progression through activation of mitogenesis and participation in the regulation of the balance between anti- and proapoptotic pathways.

Purpose: It is currently believed that cancer procoagulant (CP), an enzymatic protein, is a product of malignant neoplastic cells. The present study was designed to test whether it is also synthesized by benign neoplastic cells, namely uterine leiomyomas., Materials and Methods: We determined the activity of CP in the blood serum of women with uterine leiomyomas (N = 24), normal women (N = 15), and genital cancer patients (N = 6) by the coagulative method according to Gordon and Benson. Also, the CP activity in 10% tissue homogenates of uterine leiomyomas, normal uterine muscle and tissues of cervical and endometrial carcinoma was determined by the chromogenic method according to Colucci et al., Results: The mean CP activity in the sera of women with uterine leiomyomas was 181.1 seconds (s) +/- 19.9 s, in healthy women--293.2 s +/- 33.8 s, and in genital cancer patients--78.8 +/- 18.5 s (all differences: p < 0.001). Similarly, in homogenates of uterine leiomyomas the CP activity was 19.6 +/- 3.8 nmoles pNa/ml, in normal uterine muscle it was 13.2 +/- 2.2 nmoles pNa/ml, and in cancerous tissue--28.0 +/- 6.6 nmol pNa/ml (all values being significantly different from each other). There was a strong correlation (r = -0.8122; p < 0.001) between the CP activity in uterine leiomyomas and serum activity, suggesting that the source of the serum CP activity was from the leiomyoma. The coagulation time of 120 to 240 s by the Gordon and Benson method supported the diagnosis of uterine leiomyoma, and a value below 120 s--the suspicion of genital cancer., Conclusions: Uterine leiomyomas, representing benign genital neoplasia, synthesize CP and are the likely origin of CP activity in blood, as has been described for malignant tumors, but to a lesser degree. There may be a role for CP as a tumor marker of genital neoplasia.

Objectives: Cancer procoagulant (CP) is a sulfhydryl proteinase thought to be synthesized mainly by neoplastic cells. Consequently, increased CP activity in blood serum was interpreted as being associated with the presence of a proliferative process in the host's body. To date, CP activity has not been systematically studied in cases of genital carcinoma. The present study is aimed at evaluation of CP activity in women with genital carcinoma., Design: A case-controlled study backed up by histopathological examination., Materials and Methods: Peripheral blood was sampled preoperatively in a sterile manner from an antecubital vein, from 16 women with cervical carcinoma and 15 women with uterine carcinoma. Blood for the reference group of 12 healthy women was obtained in an identical manner after an overnight fast. The CP activity in serum was determined using the coagulative method according to Gordon and Benson, and was expressed as coagulation time in seconds (s). The CP activity in 10% tissue homogenates (in saline) of genital cancer was determined by the chromogenic method according to Colucci et al., Results: The mean CP activity in serum of women with cervical carcinoma (78.28 +/- 15.25 s) and of women with uterine carcinoma (79.63 +/- 12.02 s) was significantly different (P < 0.0001) from the respective values found in healthy women (281.33 +/- 43.19 s). The CP activity in neoplastic tissue was 28.50 +/- 6.40 nmol pNa/mL for cervical carcinoma, and 28.31 +/- 3.92 nmol pNa/mL for uterine carcinoma, both values being significantly higher (P < 0.0009) than the activity found in the normal tissues. There was no established relationship between neoplastic CP activity and FIGO staging of the disease., Conclusions: This is the first study to demonstrate the concomitant presence of CP activity in serum and neoplastic tissue of women with genital carcinoma. These patients have decreased coagulation time and thus are likely to develop coagulation disturbances in the course of their cancer. There may be a role for CP as a tumor marker of genital carcinoma.

The aim of our study was to estimate morphometric parameters of synaptophysin (Syn-38) immunoreactive ganglion cells in colorectal cancer (within and at various distances from neoplastic infiltration) in postoperative material from 60 patients. We analysed the intensity of Syn-38 expression in Auerbach ganglion neurones, mean number of these cells in the ganglion, and their longitudinal and transverse diameters. The results showed a statistically significant reduction in the number of neurones in intramural ganglia of the large intestine located in neoplastic infiltration and in its close proximity. The size of ganglion cells was directly proportional to the distance from cancer infiltration and inversely proportional to Syn-38 content, which may be explained by degenerative changes and dysfunction of these cells. This correlation was significant in the case of cells with the cytoplasmatic Syn-38 immunoreactivity pattern, but did not refer to the cells with perimembranous pattern, which seemed to be undamaged. Morphometric analysis of synaptophysin immunoreactive ganglion cells in Auerbach plexus in colorectal cancer may be a new useful marker for the description of changes in the intestinal nervous system as well as a prognostic factor for colorectal cancer.

Breast cancer is often relatively slow growing, but at diagnosis about 40% of patients have regional spread to at least one axillary node. It has been shown that unrelated clones are in primary breast carcinomas. There is possibility that only a small subpopulation of the cells of the primary tumour (PT) metastasis. It has been shown that Ki-67 protein is a useful marker in histopathology, which is present during all active phases of the cell cycle and making possibility to assess growth fraction of tumour cells. The purpose of the study was to evaluate the expression of Ki-67 and comparison between the PTs and MRLNs as well as to estimate the relationships between Ki-67 and the chosen anatomoclinical features of the breast cancer. Immunohistochemical analyses for Ki-67 were performed on the PTs (69 cases without primary chemotherapy) and MRLNs (33 cases) of breast cancer. Increased expression of Ki-67 in PTs significantly correlated with pT2 stage of tumours (p < 0.05) and grade G3 (p < 0.04), but there was not relationship with lymph node status. Expression of Ki-67 positively correlated between PTs and MRLNs (p < 0.001). Comparison between PTs and matching MRLNs revealed that 23 (69.7%) cases showed a convergence between PTs and matching MRLNs with regard to negative or positive staining. We would like to emphasize the importance of studies concerning the proteins involved in proliferation in MRLNs, because knowledge about heterogeneity between PTs and MRLNs could shed light on tumour biology and may lead to development of more effective anti-cancer therapies.

Oral papilloma is the most frequent benign tumor of the oral cavity but its biological potential for malignant transformation is still to be evaluated. The alteration of apoptosis and uncontrolled cell proliferation is considered to be an important factor in oral tumorigenesis. The aim of our study was to evaluate by immunohistochemistry P53, Bcl-2, CD44 and PCNA expression in oral papillomas with and without dysplasia. We examined a series of 55 oral papillomas, including 12(21.8%) cases of papillomas with epithelial dysplasia. Staining patterns were correlated with sex, age, tumor location, size and presence or absence of epithelial dysplasia. P53 showed positive reaction in 70.9%, PCNA in 80%, CD44 in 50.9% and Bcl-2 in 21.8% of papillomas. There was no correlation between sex, age, tumor size, location and presence of dysplastic epithelium in papillomas. We observed a statistically significant correlation between Bcl-2, CD44 expression and presence of epithelial dysplasia in papillomas. Coexistence of PCNA and P53 positive immunostaining was observed. Papillomas with overexpression of P53 and PCNA showed negative reaction for CD44 protein. The results of our study suggest that overexpression of P53 and PCNA might be an early event in oral tumorigenesis, whereas CD44 and Bcl-2 are potential markers of epithelial dysplasia in oral papillomas.