Cyclooxygenase-2 regulates the degree of apoptosis by modulating Bcl-2 protein in pleomorphic adenoma and mucoepidermoid carcinoma of the parotid gland

Conclusion These results suggest that COX-2 and bcl-2 protein were overexpressed and that apoptosis was reduced in MEC compared to PMA, and that COX-2 may regulate the degree of apoptosis by modulating bcl-2 protein in PMA and MEC.

Objective Cyclooxygenase (COX)-2 plays a crucial role in tumorigenesis and overexpression of COX-2 in vitro accompanied by overexpression of bcl-2 protein has been shown to reduce apoptosis. The purpose of this study was to verify that COX-2 regulates the degree of apoptosis by modulating bcl-2 protein in benign and malignant parotid gland tumors.

Material and methods We examined archival formalin-fixed, paraffin-embedded tissue sections of 10 pleomorphic adenomas (PMAs) and 10 mucoepidermoid carcinomas (MECs) by immunostaining with anti-COX-2, anti-bcl-2 and anti-single-stranded DNA (ssDNA) antibodies. Labeling indices of the three antibodies were calculated using computer-assisted image analysis.

Results Labeling indices (mean±SD) of anti-COX-2 antibody in PMA and MEC were 2.05±1.30 and 11.2±2.95, respectively (p<0.001), those of anti-bcl-2 antibody were 2.00±1.28 and 9.68±4.05, respectively (p<0.001) and those of anti-ssDNA antibody were 8.06±2.54 and 2.08±1.47, respectively (p<0.001). Correlation coefficients between the labeling indices of anti-COX-2 antibody and anti-bcl-2 antibody, anti-bcl-2 antibody and anti-ssDNA antibody and anti-COX-2 antibody and anti-ssDNA antibody were 0.88, ?0.75 and ?0.76, respectively (p<0.001).     

The expression of six biomarkers in the four most common ovarian cancers: correlation with clinicopathological parameters

This study aimed to evaluate the relationship of fascin‐1, matrix metalloproteinase (MMP)‐2, MMP‐9, cortactin, survivin, and epidermal growth factor receptor (EGFR) expression with clinicopathological parameters for the four most common ovarian surface epithelial carcinomas. Six biomarkers were investigated immunohistochemically using tissue microarrays of 185 specimens including 79 serous cystadenocarcinomas, 47 mucinous cystadenocarcinomas, 45 endometrioid adenocarcinomas, and 14 clear cell carcinomas. The four most common ovarian carcinomas showed significant expression of fascin‐1, cortactin, survivin, and EGFR, but not of MMP‐2 and MMP‐9. In addition, higher immunostaining scores for fascin‐1 in mucinous cystadenocarcinomas correlated with T stage, N stage, American Joint Committee on Cancer AJCC clinical stage, and a poorer survival rate; for cortactin in serous cystadenocarcinomas correlated with T stage; for cortactin in clear cell carcinomas correlated with T and clinical AJCC stages; and for survivin in clear cell carcinomas correlated with T stage and AJCC clinical stage. In addition, higher immunostaining scores for fascin‐1, cortactin, and survivin correlated with poorer tumor differentiation in serous, mucinous, and endometrioid adenocarcinomas. Thus, the expression of fascin‐1, cortactin, and survivin may be helpful in evaluating the aggressiveness of ovarian mucinous, serous, and clear cell adenocarcinoma. Additionally, the expression of fascin‐1 may be an independent prognostic risk factor in mucinous cystadenocarcinoma.     

Aldehyde reductase activity in the antennae of Helicoverpa armigera

In the present study, we identified two aldehyde reductase activities in the antennae of Helicoverpa species, NADH and NADPH‐dependent activity. We expressed one of these proteins of H. armigera, aldo‐keto reductase (AKR), which bears 56% identity to bovine aldose reductase, displays a NADPH‐dependent activity and is mainly expressed in the antennae of adults. Whole‐mount immunostaining showed that the enzyme is concentrated in the cells at the base of chemosensilla and in the nerves. The enzyme activity of H. armigera AKR is markedly different from those of mammalian enzymes. The best substrates are linear aliphatic aldehydes of 8–10 carbon atoms, but not hydroxyaldehydes. Both pheromone components of H. armigera, which are unsaturated aldehydes of 16 carbons, are very poor substrates. Unlike mammalian AKRs, the H. armigera enzyme is weakly affected by common inhibitors and exhibits a different behaviour from the action of thiols. A model of the enzyme suggests that the four cysteines are in their reduced form, as are the seven cysteines of mammalian enzymes. The occurrence of orthologous proteins in other insect species, that do not use aldehydes as pheromones, excludes the possibility of classifying this enzyme among the pheromone‐degrading enzymes, as has been previously described in other insect species.     

Advantages of immunostaining over DNA analysis using PCR amplification to detect p53 abnormality in long-term formalin-fixed tissues of human colorectal carcinomas

To study the appropriate period for formalin fixation in order to detect p53 abnormalities in formalin-fixed tissue, we used seven surgically resected human colorectal cancer specimens. The immunohistochemical reactivity of p53 immunostaining and amplification of DNA by polymerase chain reaction (PCR) of the p53 gene were compared after various periods of 10% formalin fixation (1 day, and 1, 2, 4, and 8 weeks). For comparative immunostaining, we used the monoclonal antibody Ki-67 (MIB-1), and for comparative polymerase chain reaction (PCR), K-ras at codon 12 was amplified. Immunostaining was performed by the streptavidin-biotin method with microwave retrieval, and PCR amplifications were performed by the nested PCR method. p53 and Ki-67 immunoreactivity did not change essentially for up to 2 weeks and 1 week, respectively, of formalin fixation. PCR amplification for p53 at exon 8 and K-ras at codon 12 was successful until 1 day and 2 weeks, respectively, of formalin-fixation for the specimens of all seven cases. Thereafter, the amplification tended to worsen as the fixation time lengthened. Further, the DNA was more successfully amplified in the second PCR than in the first. These results suggest that to detect p53 abnormality in specimens that have been formalin-fixed for long periods, immunohistochemical staining may have advantages over DNA analysis with PCR amplification. Received Aug. 25, 1997; accepted Mar. 27, 1998     

Thymidylate synthase expression in primary colorectal tumours is correlated with its expression in metastases

Objective. Thymidylate synthase (TS) is the rate-limiting enzyme in the synthesis of pyrimidine nucleotides and as such a critical target for fluoropyrimidines, which are widely used in the treatment of colorectal cancer (CRC). The purpose of this study was to investigate TS expression in the primary tumours (PTs) and their metastases (M) in advanced CRC. Material and methods. TS expression was determined immunohistochemically in paraffin-embedded biopsies of PT-M pairs in 39 CRC patients, as related to the clinical data. Results. There was no difference in the mean TS index of PTs compared with that of M, 1.25 and 1.14, respectively (p=0.12). TS expression of PTs was above the mean more often than that of M (61.5% and 41.0%, respectively, p=0.035). High TS expression in PTs was significantly related to high expression in M (the Fisher exact test, p=0.001). Using the absolute index values, TS expression in PT and M was significantly correlated (Pearson R=0.501, p=0.001). In 29/39 (74.3%) pairs, PT and M had concordant expression levels (Cohen's kappa 0.508, 95% CI 0.260–0.756, p=0.001; intraclass correlation coefficient (ICC) = 0.679, 95% CI 0.358–0.836, p=0.0001). No significant association was found between TS expression and any of the clinicopathological variables, disease outcome (DFS, DSS) or its response to treatment in univariate or multivariate analysis. Conclusions. Albeit usually higher, TS expression in PT was closely correlated with TS expression in M. This suggests that measurement of TS in primary CRC accurately predicts TS expression in subsequent metastases, which may help in selecting those patients most likely to respond to 5-FU-based regimens.     

Expression of Survivin and Cortactin in Colorectal Adenocarcinoma: Association with Clinicopathological Parameters

Objective: Survivin and cortactin are factors that promote tumor progression. We tested the hypothesis that survivin and cortactin expressions correlate with the clinico-pathological parameters of colorectal adenocarcinomas and survival time. Methods: Immunohistochemical analysis of survivin and cortactin were performed using tissue microarrays of 119 specimens from 18 well, 50 moderately, and 27 poorly differentiated colorectal adenocarcinomas and 24 colorectal adenomas with dysplasia. As control, 10 specimens of normal colorectal epithelia were included. Results: The percentage of cells immunostained and the immunostaining scores for survivin and cortactin were all significantly higher in well-, moderately, and poorly differentiated colorectal adenocarcinomas than in normal colorectal epithelia. The survivin immunostaining score was significantly correlated with T, M, and AJCC/TNM stages (p `0.05). For cortactin, the score was significantly correlated with T and M stages (p ` 0.05). Higher survivin immunostaining score was associated with higher mortality. Conclusions: Higher expression of survivin and cortactin correlates significantly with tumor stages and shorter survival time. Survivin and cortactin may be good biomarkers of aggressiveness of colorectal adenocarcinomas. Our findings require validation in independent cohorts and these data support the potential targeting of survivin and cortactin for the development of novel therapeutic strategies.     

Freshly prepared immune complexes with intermittent microwave irradiation result in rapid and high-quality immunostaining

We have previously reported that intermittent microwave irradiation shortened the primary or secondary antibody incubation time to 10 min in a special moist chamber. To achieve precise immunostaining within 1h, we attempted to generate a novel procedure, "freshly prepared immune complex with intermittent microwave irradiation (f-IC-M)". The advantage of this immunostaining procedure lies in a one-step incubation instead of primary and then secondary antibody application. In this study, we employed five primary antibodies to examine the efficiency and quality of this procedure. As expected, every primary antibody examined brought about precise immunostaining within 45 min for formalin-fixed, paraffin-embedded sections, and within 15 min for frozen sections. In addition, this procedure is able to generate double-immunoenzymatic staining with different enzyme-labeled primary antibodies if desired. As any combination of primary and secondary antibodies is possible by this one-step application, f-IC-M increases the efficiency of immunostaining without losing quality. Therefore, this procedure is able to rapidly provide diagnostic information to the pathologists.     

Increased levels of IL-5 positive peripheral blood eosinophils and lymphocytes in mild asthmatics after allergen inhalation provocation

BACKGROUND: In allergic inflammation eosinophils and TH2-like lymphocytes are supposed to be the major effector cells and considered to contribute as cellular source of the key cytokine interleukin (IL)-5. OBJECTIVE: The purpose of this study was to enable detection of IL-5 containing leucocytes and to investigate whether the number of these cells in the blood circulation differed between healthy and asthmatics before and after allergen provocation. METHODS: The distribution of intracellular IL-5 in human peripheral blood eosinophils (PBE) and lymphocytes (PBL) has been investigated using fixation and cell membrane permeabilization with octyl-glucopyranoside, the FOG-method, and flow cytometry. The intracellular staining was performed on leucocytes without any prior purification and in vitro stimulation. The specificity of IL-5 binding to intracellular compartment of both PBE and PBL was confirmed by complete inhibition with human recombinant IL-5. RESULTS: Preformed intracellular IL-5 was detected in the main population of PBE (> 70%) in both healthy individuals and asymptomatic patients. Moreover, preformed intracellular IL-5 was also detected in 4.8% and 2.4% of PBL from healthy individuals and asymptomatic patients, respectively. There was a correlation between the absolute number of PBE and IL-5 positive PBE. In patients with pollen-related asthma, the number of IL-5 positive PBE and PBL increased significantly 24 h after an allergen inhalation provocation (P < 0.05). In the healthy control group no differences regarding IL-5 positive PBE and PBL were obtained pre- and post-allergen challenge. CONCLUSIONS: In patients with mild allergic asthma, but not in healthy individuals, allergen provocation induces an increased absolute number of IL-5 positive PBE and PBL. The reason for the relatively high number of IL-5 positive PBL is unclear, but a plausible explanation might be that other lymphocyte subsets besides CD4+ TH2 can produce IL-5. However, enumeration of IL-5 positive leucocytes may be used as an activity marker and also be a useful tool in monitoring the inflammation in asthma.     

Immunohistochemical patterns in rectal cancer: application of tissue microarray with prognostic correlations

We utilized the high-throughput tissue microarray method to characterize immunohistochemical expression patterns with correlations to prognosis in rectal cancer. Immunostaining for the markers Ki-67, Bcl-2, p53, EGFR, E-cadherin, beta-catenin, MLH1 and MSH2 was performed in 269 rectal cancers. Expression profiles were correlated to metastasis-free survival. Immunostaining revealed frequent upregulation and/or aberrant staining patterns for several of the markers, but Ki-67, p53, Bcl-2 and EGFR did not show any correlation to prognosis. However, reduced membranous staining for beta-catenin (p = 0.04), lack of cytoplasmic staining for beta-catenin (p = 0.04), reduced membranous staining for E-cadherin (p = 0.02) and lack of cytoplasmic staining for E-cadherin (p = 0.02) correlated with metastatic disease. Multivariate analysis including the factors Dukes' stage and tumor differentiation grade demonstrated increased risk of metastatic disease in tumors with lack of cytoplasmic staining for beta-catenin (HR = 3.1, p = 0.02), reduced membranous staining for beta-catenin (HR = 1.7, p = 0.06) and reduced membranous staining for E-cadherin (HR = 2.1, p = 0.06). Loss of MMR protein expression was confirmed to be a rare event in rectal cancer with loss of MLH1 staining in 3% and MSH2 in 1% of the tumors. The lack of prognostic information contributed by most of these markers suggests that single markers for prognosis may be of limited value in rectal cancer. However, altered expression of beta-catenin and E-cadherin correlated with metastatic disease, and these markers may have prognostic importance in rectal cancer.