PTEN expression profiles in colorectal adenocarcinoma and its precancerous lesions.

The aim of the study was to determine expression of the PTEN suppressor gene in colorectal adenocarcinoma and its precancerous lesions (adenomatous polyps) in correlation with common clinical and histopathological features. Forty-four patients with adenomatous polyps and 32 with primary adenocarcinoma of the colon or rectum were enrolled in the study. They underwent endoscopic removal of polyps or major surgery and postoperative adjuvant chemo- and radiotherapy depending on staging of the disease. No patient had received chemotherapy and/or radiotherapy before the surgery. PTEN expression was evaluated using immunohistochemical staining on paraffin-embedded specimens and compared to clinicopathological features of tumors. In colorectal cancers, PTEN expression was found to be significantly lower than in normal intestinal mucosa and adenomatous polyps. That was associated with complete loss of PTEN expression observed more frequently in colorectal cancer, contrary to reduction of PTEN expression occurring mostly in polyps. A correlation between polyp diameter and loss of PTEN was demonstrated as well as between tumor size and TNM advanced stage and PTEN expression. The obtained results suggest that the PTEN/PI3K/Akt pathway may play an important role in early stages of sporadic colorectal carcinogenesis and reduced PTEN expression in late oncogenesis is associated with some adverse clinical and pathological features.

Analysis of PTEN expression in large intestine polyps and its relation to the recognized histopathological and clinical risk factors for cancer development in this location.

AIM OF THE STUDY: PTEN is an important gene whose protein product is double specific phosphatase holding key regulatory functions in sending signals from membrane receptors for growth factors into the cell downstreams. Its participation, mainly by PI3K/AKT signaling pathway in the pathomechanism of many malignant cancers was unambiguously confirmed. The PTEN function gets disturbed on many levels and for various reasons. Disorders of PTEN protein expression seem to be even more common in many carcinomas. The aim of the study is to enquire the meaning of PTEN expression in the cancer transformation process in large intestine glandular polyps. MATERIAL AND METHODS: The group includes 40 patients, 21 men and 19 women, age median 64 years (51-83) qualified to endoscopic removal of large intestine polyp. Tissue material obtained during polyp removal endoscopy was immediately fixed in 4% buffered formalin solution with the mixture of phosphatase activity inhibitors (PhosStop Roche). Time of fixation 24-48 h. After fixation, the material was embedded in paraffin. PTEN visualization was based on specific rabbit monoclonal antibodies (Cell Signaling). The expression of PTEN protein in large intestine and rectum polyps was marked by a semi-quantitative method and an attempt to correlate the results with the acknowledged clinical and histopathological malignancy risk factors was undertaken. RESULTS: Loss or weakening of protein expression was found in 45% cases. Moreover, the relationship between polyp diameter and a loss of PTEN expression was proved. The received results can indicate a significant participation of PTEN gene in early oncogenesis stages of large intestine cancer.

Cardiocyte nuclear chromatin density correlates with transplanted heart left ventricular mass.

INTRODUCTION: Cardiocyte hypertrophy is accompanied by polyploidy, seen as a decrease in chromatin density in the enlarged nucleus. Repeated biopsies of a transplanted heart offer the possibility of a dynamic evaluation of these phenomena. The aim of this work was an evaluation of cardiocyte nuclear chromatin density in transplanted hearts during long-term follow-up. MATERIALS AND METHODS: The material encompassed myocardial biopsy specimens taken during the first week, first month, and then on an annual basis up to 10 years after surgery. Only biopsy specimens with no rejection were considered (grade "0" International Society for Heart and Lung Transplantation [ISHLT] 122 biopsy specimens). The control group consisted of 7 donor heart specimens. We evaluated the optical density-mean gray level-of cardiomyocyte nuclear chromatin. We determined correlations of this index with the nuclear area, and with left ventricle ultrasound measurements, using correlation analysis. RESULTS: The chromatin mean gray level decreased with time, correlating positively with interventricular septum thickness, left ventricle posterior wall diameter, and left ventricular mass. Analysis of individual periods showed a significant positive correlation of the mean grey level with the cardiocyte nuclear surface in year 3, 4, and 9 after transplantation, thereby suggesting the occurrence of polyploidy at those times. The significant negative correlation of these values (1 week and 1 year) indicated normalization of early cardiocyte hypertrophy. CONCLUSIONS: With the passage of time chromatin condenses, leading to pyknosis. The activity of cardiocyte chromatin correlated with left ventricular hypertrophy. Compensatory cardiomyocyte polyploidy is a periodical phenomenon.

[Prognostic molecular markers in oral and lip squamous cell carcinoma--evaluation of expression and its significance]. / Ekspresja niektórych molekularnych markerów immunohistochemicznych i ocena ich znaczenia prognostycznego w rakach plaskonablonkowych jamy ustnej i wargi.

INTRODUCTION: Head and neck cancer treatment optimization and individualization has become possible due to the implementation of the prognostic and predictive molecular markers in diagnostics. AIM: The aim of this study was an attempt to determine which of the investigated molecular markers may have prognostic and predictive value in head and neck cancers. MATERIALS AND METHODS: The paraffin blocks from 47 patients with oral and lip squamous cell carcinoma (SCC) after surgical treatment in the Institute of Oncology in Gliwice in the period of 1998-2002 were investigated. For immunohistochemical studies the DAKO monoclonal antibodies were used: p53, Ki67, Cyclin D1, Cathepsin B and Cox2-Cayman Chemical antibody. Staining reactions were evaluated at 400x magnification. The average percent of staining cells was estimated in every case in the groups of patients with (N+) and without (No) node metastases. The results were subsequently juxtaposed with selected clinical and histological parameters. Statistical analysis was performed with Mann-Whitney and Kruskal-Wallis tests and the log rank test with a significance level of 0.05 (p = 0,05). RESULTS: Significantly higher expression of Ki67 in N+ patients (p = 0,010) were recorded, although average staining in the group of treated and the group of unhealed patients was statistically insignificant. Cathepsin B expression (<20% and > 20%) was correlated with 3 year-long survival and a slight higher average staining (33,5%) in unhealed in comparison with treated patients (29,0%) was notified. Everage expression of p53 in unhealed patients (33,1%) was slightly higher than in treated ones (28,4%). Weaker Cyclin D1 expression (<10%) correlated with higher disease free survival. Average Cycline D1 staining in the groups of unhealed patients (19,6%) was higher than in the treated ones (12,0%). There were no significant differences in COX-2 staining in correlation with clinical and histological parameters. CONCLUSIONS: Lower expression of Cyclin D1 and Cathepsin B in neoplastic cells correlated with higher percentage of disease free survival what suggests the prognostic value of these markers. Higher proliferation activity of primary tumor neoplastic cells correlated with node metastases what may has the predictive value in the course of the disease.The different markers expressions observed in the different oral cavity localizations confirm the necessity to select patients for further investigations with respect to uniform disease changes topography.

PTEN as a prognostic and predictive marker in postoperative radiotherapy for squamous cell cancer of the head and neck.

BACKGROUND: Tumor suppressor PTEN is known to control a variety of processes related to cell survival, proliferation, and growth. PTEN expression is considered as a prognostic factor in some human neoplasms like breast, prostate, and thyroid cancer. METHODOLOGY/PRINCIPAL FINDINGS: In this study we analyzed the influence of PTEN expression on the outcome of a randomized clinical trial of conventional versus 7-days-a-week postoperative radiotherapy for squamous cell cancer of the head and neck. The patients with cancer of the oral cavity, oropharynx, and larynx were randomized to receive 63 Gy in fractions of 1.8 Gy given 5 days a week (CF) or 7 days a week (p-CAIR). Out of 279 patients enrolled in the study, 147 paraffin blocks were available for an immunohistochemical assessment of PTEN. To evaluate the prognostic value of PTEN expression and the effect of fractionation relative to PTEN, the data on the outcome of a randomized clinical trial were analyzed. Tumors with a high intensity of PTEN staining had significant gain in the loco-regional control (LRC) from p-CAIR (5-year LRC 92.7% vs. 70.8%, for p-CAIR vs. CF, p = 0.016, RR = 0.26). By contrast, tumors with low intensity of PTEN did not gain from p-CAIR (5-year LRC 56.2% vs. 47.2%, p = 0.49, RR = 0.94). The intensity of PTEN highly affected the LRC in a whole group of 147 patients (5-year LRC 80.9% vs. 52.3% for high vs. low PTEN, p = 0.0007, RR = 0.32). In multivariate Cox analysis, including neck node involvement, EGFR, nm23, Ki-67, p53, cyclin D1, tumor site and margins, PTEN remained an independent predictor of LRC (RR = 2.8 p = 0.004). CONCLUSIONS/SIGNIFICANCE: These results suggest that PTEN may serve as a potent prognostic and predictive marker in postoperative radiotherapy for high-risk squamous cell cancer of the head and neck.

Advanced glycation end product accumulation in the cardiomyocytes of heart failure patients with and without diabetes.

BACKGROUND: Non-enzymatic coupling of protein and lipid cellular structures with glucose leading to the formation of advanced glycation end products (AGE) plays a role in aging and the development of diabetic complications, but its contribution to myocardial pathology is unclear. We aimed to assess the role of heart failure on AGE formation in patients with or without diabetes mellitus type 2 (DM2). MATERIAL/METHODS: Heart tissue specimens from 136 patients undergoing transplantation were grouped as follows: 14 cases of ischemic cardiomyopathy (ICM) and DM2, 8 cases of dilated cardiomyopathy (DCM) and DM2, 67 cases of ICM without DM2, and 47 cases of DCM without DM2. Fourteen heart samples were from the autopsies of patients with DM2 without heart disease, and 20 heart samples were from organ donors in whom the heart was wasted. AGE deposits were localized immunohistochemically counted using a semiquantitative scale and characterized by their staining pattern. RESULTS: Positive staining was present in all samples from both cardiomyopathy groups with DM2, in 71% of healthy hearts from the DM2 subjects, in 51% of ICM non-diabetic hearts, and in 38% of DCM non-diabetic hearts, and in only 15% of the organ donors. Mixed-diffuse and granular AGE patterns were characteristic for DM2, while a diffuse pattern was more frequently observed in heart failure patients without diabetes. The semiquantitative results supported increased AGE accumulation in patients with DM2 and/or cardiomyopathy. CONCLUSIONS: The amount of AGE in cardiomyocytes increases significantly in both diabetes and heart failure, with a staining pattern typical for each condition.

Advanced glycation end-products in myocardium-supported vessels: effects of heart failure and diabetes mellitus.

BACKGROUND: Disturbed glucose metabolism, particularly in diabetes, is an important but not the sole factor leading to advanced glycation end-product (AGE) formation. The AGE amount and its distribution in cardiopathic myocardial tissues in the presence or absence of diabetes are not well documented. The aim of this study was to assess AGE deposition in unaffected myocardial vessels in heart failure patients with and without diabetes mellitus type 2 (DM2) undergoing transplantation. METHODS: The following groups were established: 14 hearts harvested from subjects with ischemic cardiopathy and DM2; 8 hearts from subjects with dilated cardiopathy with DM2; 67 hearts from subjects with ischemic cardiopathy; 47 hearts from subjects with dilated cardiopathy; and 14 hearts from autopsy cases with diagnosed DM2. A control group consisted of 20 heart donors. AGE localization was determined immunohistochemically in tissue sections. A semi-quantitative scale was used to assess reaction intensity in arteries, arterioles, capillaries, venules and veins. RESULTS: Both types of cardiomyopathy increased AGE accumulation in intramyocardial veins more than in arteries. The presence of DM2 significantly increased AGE in arterioles and capillaries, especially when coexisting with cardiomyopathy. The type of cardiopathy did not influence the pattern of AGE accumulation in myocardial vessels. CONCLUSION: Both chronic heart failure and DM2 intensified AGE pathology and changed the susceptibility of myocardial vasculature to glycation. However, chronic heart failure increases AGE deposition mostly in veins, whereas DM2 predisposes arterioles to AGE accumulation.