Inter-Tissue and Intra-Tissue Co-Expression Networks in Human Metabolism: Morphological Evaluation of the Link Between Transcription Factors ERß and NFAT in Morbid Obesity.

BACKGROUND: Estrogen receptor ß (ERß) plays an important role in human metabolism and some of its metabolic actions are mediated by a positive "cross-talk" with Nuclear Factor of Activated T cells (NFAT) and the key metabolic transcriptional coregulator Transcriptional Intermediary Factor 2 (TIF2). INTRODUCTION: Our study is an "in situ" morphological evaluation of the communication between ERß, NFAT and TIF2 in morbid obesity. Potential correlations with clinicopathological parameters and with the presence of diabetes and non-alcoholic fatty liver disease (NAFLD) were also explored. The aim of the present study was to determine the role of ERß and NFAT in the underlying pathophysiology of obesity and related comorbidities. We have investigated the expression of specific proteins using immunochemistry methodologies. METHODS: Our population consists of 50 morbidly obese patients undergoing planned bariatric surgery, during which biopsies were taken from visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), skeletal muscle (SM), extramyocellular adipose tissue (EMAT) and liver and the differential protein expression was evaluated by immunohistochemistry. RESULTS: We demonstrated an extensive intra- and inter-tissue co-expression network, which confirms the tissue-specific and integral role of each one of the investigated proteins in morbid obesity. Moreover, a beneficial role of ERß and NFATc1 against NAFLD is implicated, whereas the distinct roles of TIF2 still remain an enigma. CONCLUSION: We believe that our findings will shed light on the complex underlying mechanisms and that the investigated biomarkers could represent future targets for the prevention and therapy of obesity and its comorbidities.

SRC-3/AIB-1 may Enhance Hepatic NFATC1 Transcription and Mediate Inflammation in a Tissue-Specific Manner in Morbid Obesity.

BACKGROUND: Obesity is a global epidemic which is associated with several cardiometabolic comorbidities and is characterized by chronic, low grade systemic inflammation. Numerous biomarkers have been implicated in the pathophysiology of the disease, including transcription factors and coregulators. Steroid Receptor Coactivator (SRC)-family represent the master regulators of metabolic pathways and their dysregulation is strongly associated with numerous metabolic disorders. METHODS: 50 morbidly obese patients participated in the present study. Biopsies were collected from visceral adipose tissue, subcutaneous adipose tissue, skeletal muscle, extra-myocellular adipose tissue and liver. We evaluated the differential protein expression of NFATc1, SRC-2/TIF-2, SRC-3/AIB-1 and inflammatory biomarkers CD68 and CD3 by immunohistochemistry. The current study was designed to determine any correlations between the transcription factor NFATc1 and the SRC coregulators, as well as any associations with the inflammatory biomarkers. RESULTS: We identified SRC-3 as a hepatic NFATc1 coactivator and we demonstrated its possible role in energy homeostasis and lipid metabolism. Moreover, we revealed a complex and extensive intraand inter-tissue network among the three main investigated proteins and the inflammatory biomarkers, suggesting their potential participation in the obesity-induced inflammatory cascade. CONCLUSION: Steroid receptor coactivators are critical regulators of human metabolism with pleiotropic and tissue-specific actions. We believe that our study will contribute to the better understanding of the complex multi-tissue interactions that are disrupted in obesity and can therefore lead to numerous cardiometabolic diseases. Further on, our present findings suggest that SRC-3/AIB-1 could constitute possible future drug targets.

Inter-tissue expression patterns of the key metabolic biomarker PGC-1α in severely obese individuals: Implication in obesity-induced disease.

OBJECTIVE: PGC-1α is already known as a significant regulator of mitochondrial biogenesis, oxidative phosphorylation and fatty acid metabolism. Our study focuses on the role of PGC1α in morbid obesity, in five different tissues, collected from 50 severely obese patients during planned bariatric surgery. METHODS: The investigated tissues included subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), skeletal muscle (SM), extramyocellular adipose tissue (EMAT) and liver. PGC1α expression was investigated with immunohistochemistry and evaluated with microscopy. RESULTS: Our findings highlighted significant positive inter-tissue correlations regarding PGC-1α expression between several tissue pairs (VAT-SAT, VAT-SM, VAT-EMAT, SAT-SM, SAT-EMAT, SM-EMAT). Moreover, we found significant negative correlations between PGC1α expression in VAT with CD68 expression in skeletal muscle and EMAT, implying a possible protective role of PGC1α against obesity-induced inflammation. CONCLUSION: Unmasking the inter-tissue communication networks regarding PGC-1α expression in morbid obesity, will give more insight into its significant role in obesity-induced diseases. PGC1α could potentially represent a future preventive and therapeutic target against obesity-induced disease, probably through enhancing mitochondrial biogenesis and metabolism.

Can obesity-induced inflammation in skeletal muscle and intramuscular adipose tissue accurately detect liver fibrosis?

OBJECTIVES: Obesity is characterized by a chronic, low grade, systemic inflammation. However, little is known about the role of skeletal muscle, which represents an active metabolic organ whose activities need to be determined. The purpose of our study was to detect relationships between skeletal muscle and adipose tissue inflammation with nonalcoholic fatty liver disease (NAFLD) and diabetes, as well as to explore associations with clinicopathological parameters. METHODS: Our study population consisted of 50 morbidly obese patients undergoing planned bariatric surgery. Biopsies were taken from visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), skeletal muscle (SM), extramyocellular adipose tissue (EMAT) and liver. The expression of CD68 and CD3 was assessed by immunohistochemistry. RESULTS: Our findings suggest a complex inter- and intra-tissue co-expression network that links obesity-induced inflammation in adipose depots and skeletal muscle with NAFLD. A novel finding is the intricate cross-talk between SM, EMAT and the liver and the probable correlation between SM, EMAT inflammation and the presence of liver fibrosis. CONCLUSIONS: Although the mechanisms of obesity-induced inflammation and its association with NAFLD and liver fibrosis are incompletely understood, our findings indicate an extensive and complex tissue network that needs to be further investigated.

Epigenetic modifications in cutaneous malignant melanoma: EZH2, H3K4me2, and H3K27me3 immunohistochemical expression is enhanced at the invasion front of the tumor.

Cancer stem cells and the misregulation of epigenetic modifications have been identified to possess a determinative role in carcinogenesis. The purpose of this study was to investigate the expression profile of EZH2 and H3K4me2 and H3K27me3, which constitute stem cell-like "bivalent" domains, in cutaneous malignant melanoma. A comparative analysis of their immunohistochemical expression between the invasion front (IF) and the inner tumor mass was also evaluated. Immunohistochemical methodology was performed on sections of 89 melanoma lesions from 79 patients. The 3 markers studied were identified in the cell nuclei of melanoma cells, nevus cells, and normal epidermal keratinocytes. A specific distribution pattern of H3K4me2 and H3K27me3 was found, as stronger levels were localized at the IF of the tumor (P = 0.034 and P < 0.01, respectively). In general, H3K4me2 and H3K27me3 levels were lower in metastatic with respect to primary melanoma cases (P = 0.0065 and P = 0.027, respectively). Advanced melanoma demonstrated significantly lower H3K4 immunohistochemical expression than did cases of lowest Clark level (I) (P = 0.038) or low Breslow depth (≤1 mm; P < 0.001). Furthermore, EZH2 expression in melanoma cells was higher compared with that in nevus cells (P = 0.02). A positive correlation between EZH2-H3K27me3 (P = 0.03) and H3K4me2-H3K27me3 (P < 0.01) in melanoma cells was also found. Our results suggest the possibility that combined immunohistochemical expression of EZH2, H3K4me2, and H3K27me3 might identify cancer cells with potential stem cell properties, particularly at the IF of this malignancy. This hypothesis should be further investigated, as many of the epigenetic changes are reversible via pharmacologic manipulations and new therapies, overpassing the resistance of advanced melanoma, may be developed.

Prognostic value of novel biomarkers in astrocytic brain tumors: nuclear receptor co-regulators AIB1, TIF2, and PELP1 are associated with high tumor grade and worse patient prognosis.

Estrogen receptors alpha (ERα) and beta (ERß) and their co-regulatory proteins are key components of complex signaling networks that specifically regulate the growth and development of various tissues and tumors. Still, their protein expression profiles and possible role in the pathogenesis of astrocytic tumors remain largely unknown. The purpose of the present study is to evaluate the differential protein expression of ΕRα, ERß, and their co-activators, AIB1, TIF2, and PELP1 in astrocytic tumors of World Health Organization (WHO) grade II-IV, using immunohistochemistry. Potential correlations with clinicopathological parameters and patient prognosis were also explored. ERα protein expression was undetectable while ERß levels were significantly decreased with progression of tumor grade (P < 0.001). High expression of ERß was an independent favorable prognostic factor on multivariate analysis (P = 0.003). Expression of AIB1, TIF2, and PELP1 was not correlated with ERß expression and followed an opposite trend, with increasing levels in high-grade relative to low-grade tumors (P < 0.001). Univariate survival analysis revealed that high AIB1, TIF2, and PELP1 expression was associated with worse prognosis (P = 0.049, P = 0.033, and P = 0.020, respectively). ERß and ER co-activators AIB1, TIF2, and PELP1 appear to play an important role in the pathogenesis and progression of astrocytic tumors and might have prognostic significance. The mechanisms underlying their involvement in astrocytic tumorigenesis, as well as their utility for prognostic and therapeutic purposes merit further investigation.

Expression of ERß and its co-regulators p300 and NCoR in human transitional cell bladder cancer.

OBJECTIVE: Several data support a possible role of estrogens in bladder carcinogenesis, mediated mainly through estrogen receptor-ß (ERß). We study the expression of ERß and its co-regulators p300 and nuclear co-repressor (NCoR) in patients with bladder cancer. PATIENTS AND METHODS: One hundred and eleven consecutive patients (74 males and 37 females), aged 23-90 years (mean 70 ± 10) diagnosed with transitional cell bladder cancer were included in this study. The control group consisted of 29 patients that underwent transurethral prostatectomy and consented to simultaneous bladder biopsies. Immunohistochemical studies took place on formalin-fixed, paraffin-embedded sections from the TUR (transurethral resection) specimens. We studied the expression of ERß, p300 and NCoR.χ(2) test was used to evaluate the relationship between the histological grade and ERß expression, grade and co-regulators expression and grade and gender. Spearman rank correlation coefficient (r) was used in order to estimate the direction and strength of correlations between histological grade and ERß-p300-NCoR expressions. The Cochran-Armitage test for trend was applied in order to examine possible trends across the ordered levels of histological grade. RESULTS: ERß was more frequently expressed in the nucleus of normal bladder epithelium compared to malignant bladder epithelium with statistical significant association (r = -0.25, p = 0.003). The p300 was expressed only in the nucleus of bladder cancer cells and a positive correlation between molecular expression and cancer progression was demonstrated (r = 0.55, p < 0.001). NCoR immunostaining was demonstrated in the nuclei of bladder cells. Nuclear staining was significantly higher in normal tissue than in cancer cells (r = -0.33, p < 0.001), with negative correlation. Furthermore, its expression in grade I tumors was significantly higher than in grade II (r = -0.46, p < 0.001) and grade III tumors (r = -0.51, p < 0.001). Thus, like ERß, NCoR expression in bladder epithelium decreased during cancer progression and loss of cell differentiation. There was no correlation between the levels of expression of the three proteins in normal bladder epithelium, but there was an inverse correlation between the nuclear expression of ERß and p300 in carcinomas (r = -3.88, p = 0.042). Statistical significant association was established when correlating ERß expression with NCoR expression (r = 0.273, p = 0.005), while co-regulators' nuclear expression did not correlate with each other (p > 0.05). CONCLUSIONS: In bladder carcinogenesis, we demonstrated inhibition in the expression of ERß and its co-repressor NCoR as well as increased expression of the co-activator p300.

Coordinated increased expression of Cyclooxygenase2 and nuclear factor κB is a steady feature of urinary bladder carcinogenesis.

OBJECTIVES: The inescapable relationship between chronic inflammation and carcinogenesis has long been established. Our objective was to investigate COX-2 and NF-κB immunohistochemical expression in a large series of normal epithelium and bladder carcinomas. METHODS: Immunohistochemical methodology was performed on formalin-fixed, paraffin-embedded sections from urinary bladder carcinomas of 140 patients (94 males and 46 females with bladder carcinomas). RESULTS: COX-2 expression is increased in the cytoplasm of bladder cells, during loss of cell differentiation (r(s) = 0.61, P-value < .001) and in muscle invasive carcinomas (P-value < .001). A strong positive association between tumor grade and nuclear expression of NFκB has been established. A positive correlation between COX-2 and nuclear NFκB immunoreactivity was observed. CONCLUSIONS: The possible coordinated upregulation of NFκB and COX-2, during bladder carcinogenesis, indicates that agents inhibitors of these two molecules may represent a possible new treatment strategy, by virtue of their role in bladder carcinogenesis.

Inverse expression of estrogen receptor-beta and nuclear factor-kappaB in urinary bladder carcinogenesis.

OBJECTIVES: To investigate the expression of nuclear factor-kappaB (NF-kappaB) and estrogen receptor-beta (ER-beta) signalling pathways in bladder urothelial carcinoma according to clinicopathological features, in order to elucidate their role during carcinogenesis. METHODS: Immunohistochemical methodology was carried out on formalin-fixed, paraffin-embedded sections from urinary bladder carcinomas of 140 patients (94 males and 46 females) who underwent transurethral resection of bladder neoplasms. Correlations between ER-beta and NF-kappaB, and tumor grade and T-stage were evaluated, along with demographic data, sex and age. RESULTS: A significant decrease in ER-beta expression in the nucleus of bladder cells during loss of cell differentiation (r(s) = -0.61, P-value < 0.001, test of trend P-value = 0.003) and in muscle invasive carcinomas (T2-T4; test of trend P-value < 0.001) was found. p65 Subunit of NF-kappaB was expressed in the nucleus and in the cytoplasm of bladder epithelial cells. A strong positive association between tumor grade and nuclear expression of NF-kappaB was shown. No correlation between NF-kappaB, nuclear or cytoplasmic staining, with T-stage was observed. An inverse correlation between ER-beta and nuclear p65 immunoreactivity was observed (r(s) = -0.45, P-value < 0.001). There was no correlation with demographic data. CONCLUSIONS: Our immunohistochemical study suggests the possible inverse regulation of NF-kappaB and ER-beta transcription factor during bladder carcinogenesis. Selective ER-beta agonists and agents, inhibitors of NF-kappaB, might represent a possible new treatment strategy for bladder urothelial tumors.

Low COX2 in tumor and upregulation in stroma mark laryngeal squamous cell carcinoma progression.

OBJECTIVES/HYPOTHESIS: Invasive squamous cell carcinomas (SCC) of the larynx, like most solid tumors, are surrounded by a reactive stroma, in which cancer associated fibroblasts (CAFs) are the predominant cell type. This mesenchymal reaction may affect cancer progression multiply. The proinflammatory enzyme cyclooxygenase-2 (COX-2) has been correlated with head and neck cancer. This study aims to explore the impact of epithelial and stromal COX-2 expression on SCC behavior. STUDY DESIGN: Retrospective case review study performed in a tertiary health center institution. METHODS: Double immunohistochemistry of COX-2 and the CAF marker alpha-smooth muscle actin (alpha-SMA) was utilized in 97 laryngeal cancer patients. Follow-up data were collected in 52 cases. RESULTS: Low COX-2 immunostaining in cancer cells was associated with advanced grade (P = .044) and shorter recurrence-free period (P = .035). CAF expression was positively correlated with the grade of the infiltrating tumor (P = .030). CONCLUSIONS: In laryngeal SCCs, COX-2 may exert its deleterious effect by alterations in the tumor microenvironment. CAF-derived, COX-2-mediated paracrine influences on malignant cells possibly facilitate cancer progression. Overlooking the stromal remodeling could account for unsuccessful treatments of epithelial neoplasms.

Expression of ERalpha, ERbeta and co-regulator PELP1/MNAR in colorectal cancer: prognostic significance and clinicopathologic correlations.

BACKGROUND: Estrogen receptor beta (ERbeta) is abundantly expressed in colorectal tissue, but its role in colorectal carcinogenesis remains elusive. ER novel co-regulator, proline-, glutamic acid- and leucine-rich protein 1 (PELP1/MNAR) has been characterized, but its expression in colorectal carcinomas has not been investigated. METHODS: ERalpha, ERbeta and PELP1/MNAR protein expression were evaluated by immunohistochemistry in colorectal normal mucosa, adenomas and adenocarcinomas from 113 patients with colorectal cancer. RESULTS: ERalpha expression is extremely rare in colorectal tissue and its expression does not appear to be associated with colorectal carcinogenesis. ERbeta and PELP1/MNAR were detected in the nucleus of epithelial, endothelial, inflammatory, smooth muscle cells and myofibroblasts. When intensity of staining was taken into account, the expression of both proteins was significantly increased in epithelial cells of carcinomas compared to normal mucosa. ERbeta expression in epithelial cells was correlated with decreased disease progression - free survival. PELP1/MNAR overexpression in epithelial cells was found to be an independent favorable prognostic factor. Additionally, the expression of both proteins was significantly increased in stromal myofibroblasts of carcinomas compared to adenomas and normal mucosa. CONCLUSION: ERbeta and PELP1/MNAR appear to be involved in colorectal tumorigenesis and might have prognostic significance.

Retinoid X receptor overexpression desensitizes laryngeal epithelium to carcinogenic effects associated with epidermal growth factor receptor upregulation.

OBJECTIVE: Squamous cell carcinomas (SCCs) of the larynx are sequelae of hyperplastic and dysplastic lesions. Epidermal growth factor receptor (EGFR) is found frequently overexpressed in SCCs of the head and neck, although its regulatory role is not fully elucidated. Conversely, retinoid X receptor alpha (RXRalpha) mediates the reversing effects of retinoids on head and neck carcinogenesis. We examined the expression of EGFR in relation to the progress of laryngeal tumorigenesis and how this association is modulated by concurrent RXR presence. DESIGN: A retrospective study. SETTING: A basic research anatomy laboratory, operating within a tertiary care institution. MATERIALS: Tissue samples from 129 patients with premalignant or malignant laryngeal lesions. METHOD: Paraffin-section immunohistochemistry. MAIN OUTCOME MEASURES: EGFR immunoreactivity in relation to histopathology progression, in both the presence and absence of RXR immunoexpression. RESULTS: EGFR was upregulated along the epithelial deterioration toward neoplasia (p < .001) but was unaffected by tumour grade. In RXRalpha-positive cases, a markedly stronger induction of EGFR occurred with malignant transformation compared with the epithelia immunonegative for the nuclear receptor. CONCLUSION: This study suggests that RXRalpha confers to squamous cells a shielding effect against excessive mitogenic stimulation, which might be EGFR dependent. RXR-positive patients manifesting resistance to anti-EGFR agents could benefit from rexinoid administration.

Estrogen signaling in colorectal carcinoma microenvironment: expression of ERbeta1, AIB-1, and TIF-2 is upregulated in cancer-associated myofibroblasts and correlates with disease progression.

Epidemiological and molecular data suggest the involvement of estrogen signaling in colorectal tissue, mediated mainly through estrogen receptor beta (ERbeta). Estrogens may mediate their effects in epithelial cells indirectly by acting on stromal cells. Expression of ERalpha, ERbeta1, and the ER coregulators, amplified in breast cancer-1 (AIB-1) and transcriptional intermediary factor 2 (TIF-2), was evaluated in myofibroblasts of 107 colorectal carcinomas, 77 paired samples of normal mucosa, and 29 adenomas by immunohistochemistry. Double immunostaining with a-SMA was used to identify the myofibroblasts of normal tissue, adenomas, and cancer microenvironment. ERalpha was not expressed in stromal cells. Nuclear expression of ERbeta1, AIB-1, and TIF-2 in myofibroblasts gradually increased from normal mucosa, through adenomas, to carcinomas. Cytoplasmic ERbeta1 and TIF-2 expression was enhanced in carcinomas compared to normal mucosa and adenomas. Enhanced nuclear and cytoplasmic ERbeta1 expression and elevated nuclear AIB-1 expression were more frequently noted in myofibroblasts of carcinomas of advanced stage. ERbeta1 expression in cancer-associated myofibroblasts correlated to AIB-1 and TIF-2 expression. None of the markers correlated with patients' prognosis. Our findings imply that ERbeta1-dependent (genomic and non-genomic) and ER-coregulator-dependent (AIB-1, TIF-2) signal transductions in myofibroblasts may be involved in the initiation and progression of colorectal carcinomas.

Estrogen receptor alpha/beta, AIB1, and TIF2 in colorectal carcinogenesis: do coregulators have prognostic significance?

PURPOSE: Estrogen receptor beta (ER beta) is abundantly expressed in colorectal tissue, but its role in colorectal carcinogenesis remains elusive. Estrogen receptor coregulators, amplified in breast cancer 1 (AIB1) and transcription intermediary factor 2 (TIF2), have been well-characterized, but their expression in colorectal carcinomas has not been investigated. MATERIALS AND METHODS: Estrogen receptor alpha (ER alpha), ER beta, AIB1, and TIF2 protein expression were evaluated by immunohistochemistry in colorectal normal mucosa, adenomas, and adenocarcinomas from 110 patients with colorectal cancer. RESULTS: ER alpha expression was rare in colorectal tissue and its expression does not appear to be associated with colorectal carcinogenesis. ER beta, AIB1, and TIF2 were detected in the nucleus of epithelial, endothelial, inflammatory, smooth muscle cells, and myofibroblasts. The expression of the three proteins was significantly increased in epithelial cells of carcinomas compared to normal mucosa. In carcinomas, a significant correlation between the levels of expression of AIB1 and TIF2 was noted. Although AIB1 overexpression was associated with local tumor invasion, it was also found to correlate independently with prolonged overall survival. CONCLUSIONS: ER beta, AIB1, and TIF2 appear to be involved in colorectal tumorigenesis and might have prognostic significance.

Expression of estrogen receptor co-regulators NCoR and PELP1 in epithelial cells and myofibroblasts of colorectal carcinomas: cytoplasmic translocation of NCoR in epithelial cells correlates with better [corrected] prognosis.

Proline-, glutamic acid-, and leukine-rich protein (PELP1) is a novel co-regulatory protein that modulates genomic and non genomic actions of estrogen receptors. Nuclear receptor co-repressor (NCoR) represses estrogen-receptor-dependent transcription. PELP1 and NCoR expression was evaluated in tissue sections from 107 formalin-fixed, paraffin-embedded colectomy specimens. Normal mucosa and adenomas were also evaluated in 77 and 29 cases, respectively. PELP1 was expressed in a dot-like pattern in the nuclei of epithelial and stromal cells. Statistical analysis revealed an increase in PELP1 expression in myofibroblasts from normal mucosa through adenomas to carcinomas. NCoR was expressed in the nuclei and the cytoplasm of epithelial cells. Nuclear expression was more common in normal mucosa, whereas cytoplasmic expression was higher in malignant epithelial cells. Additionally, NCoR was expressed in the cytoplasm of cancer-associated myofibroblasts, but was rarely noted in myofibroblasts of normal mucosa or adenomas. Cytoplasmic expression of NCoR in epithelial cells correlated with better disease-free and overall survival on univariate analysis and was an independent prognostic marker for disease-free survival on multivariate analysis. These findings suggest that deregulation of co-regulators expression in both epithelial cells and myofibroblasts may contribute to the initiation and progression of colorectal carcinoma.

Glottic versus supraglottic tumors: differential molecular profile.

Glottis and supraglottis, although anatomically interconnected, are embryologically distinct. Moreover, squamous cell carcinomas arising from these subsites, differ in terms of epidemiology, risk factors, clinical behaviour and prognosis. This study aims to explore any possible differences between their molecular profiles. We investigated in the two tumor types, the expression of epidermal growth factor receptor (EGFR), nuclear factor-kappaB (NF-kappaB) and retinoid X receptor alpha (RXRalpha), principal signal transducers associated with cancer, as well as cyclooxygenase-2 (COX-2), an enzyme induced in malignant neoplasms. The clinical material includes tumor specimens from 61 patients with laryngeal cancer of glottic or supraglottic origin. Subsite groups were matched for gender, age and histological grade. Paraffin-section immunohistochemistry was performed, to detect the aforementioned molecules. Staining patterns were membranic and cytoplasmic for EGFR, purely cytoplasmic for COX-2, nuclear for RXRalpha and cytoplasmic, as well as nuclear, for NF-kappaB. Intense EGFR and RXRalpha expression was significantly associated with glottic tumor descent (P = 0.011 and 0.001, respectively). No significant relationship was established between neoplasm location and expressions of NF-kappaB, COX-2. Our results show that tumors emerging from the two laryngeal regions, are different with regard to their molecular constitution. Upregulation of EGFR and RXRalpha in carcinomas of the glottis, might be important in the design of subsite-specific chemotherapeutic approaches.

EGF-R is expressed and AP-1 and NF-kappaB are activated in stromal myofibroblasts surrounding colon adenocarcinomas paralleling expression of COX-2 and VEGF.

BACKGROUND: COX-2 and VEGF are important triggers of colon cancer growth, metastasis and angiogenesis. Cox-2 promoter contains transcriptional regulatory elements for AP-1 and NF-kappaB transcription factors whilst vegf is a known AP-1 downstream target gene. We investigated whether stromal myofibroblasts surrounding colon adenocarcinomas express COX-2 and VEGF and whether activation of AP-1 and NF-kappaB, as well as expression of EGF-R parallel expression of COX-2 and VEGF in these cells. METHODS: Immunohistochemical methodology was performed on archival sections from 40 patients with colon adenocarcinomas. We evaluated c-FOS, p-c-JUN (phosphorylated c-JUN), p-IkappaB-alpha (phosphorylated IkappaB-alpha), EGF-R, COX-2, NF-kappaB and VEGF expression in stromal myofibroblasts surrounding colon adenocarcinomas. Double immunostaining with a-smooth muscle actin and each antibody was done to verify the expression of these molecules in stromal myofibroblasts. RESULTS: VEGF, p-IkappaB-alpha, NF-kappaB, c-FOS, p-c-JUN, EGF-R and COX-2 were expressed in stromal myofibroblasts surrounding colon adenocarcinomas in the majority of cases. EGF-R, p-IkappaB-alpha, NF-kappaB, c-FOS and p-c-JUN correlated positively with COX-2 and VEGF expression. CONCLUSION: Stromal myofibroblasts surrounding colon adenocarcinomas are an important source of VEGF and COX-2 production, while AP-1 and NF-kappaB transcription factors are activated and EGF-R is expressed in these cells and associated with COX-2 and VEGF production.

Peroxisome proliferator-activated receptor gamma expression correlates with the differentiation level of normal, premalignant, and malignant laryngeal squamous cells.

OBJECTIVE: Peroxisome proliferator-activated receptor gamma (PPAR gamma) has been implicated in the differentiation of several cell types, such as adipocytes, monocytes, and epidermal keratinocytes. This study concentrated on PPAR gamma's potential role in the maturation process of laryngeal squamous epithelium, both normal and premalignant, as well as in the differentiation grade of squamous cell carcinomas (SCCs) of the larynx. DESIGN: A retrospective study. SETTING: A basic research anatomy laboratory, operating within a tertiary care institution. MATERIALS: Clinical specimens from 89 subjects with normal laryngeal epithelium and hyperplastic, dysplastic, or malignant lesions. METHODS: Paraffin-section immunohistochemistry. MAIN OUTCOME MEASURES: Strength and extent of PPAR gamma presence, specified by stain intensity and ratio of stained cells, respectively. RESULTS: All stratified histologic categories, that is, normal mucosa, hyperplasia, and dysplasia, displayed a significant increase in PPAR gamma expression in suprabasal differentiated layers compared with basal undifferentiated ones (rho < .01). Hyperplasia and dysplasia manifested lower and higher levels of PPAR gamma, respectively, in comparison with normal epithelium. Whereas grade Pi and III SCCs were characterized by equal expression, well-differentiated tumours possessed considerably raised receptor content. Fluctuations of expression among various histologic categories lacked statistical significance, however. CONCLUSIONS: Our results suggest PPAR gamma induction throughout squamous cell differentiation in normal, premalignant, and malignant epithelia.

HER-3 in colorectal tumourigenesis: from mRNA levels through protein status to clinicopathologic relationships.

INTRODUCTION: Colorectal cancer is a major cause of cancer mortality in the Western world. Although HER-3 signalling is known to be implicated in colorectal carcinogenesis, the significance of its expression, localisation and phosphorylation remains elusive. METHODS: Quantitative RT-PCR for HER-3 mRNA and immunohistochemistry for HER-3 and phosphorylated HER-3 (pHER-3) protein were performed in normal tissue, adenomas and carcinomas from 140 patients with colorectal cancer. RESULTS: HER-3 was detected both in the cytoplasm and nucleus, whereas pHER-3 was observed in the nucleus and membrane of cells. A possible switch in HER-3 topography from the nucleus to the cytoplasm during colorectal tumourigenesis is suggested. The expression of pHER-3 did not differ significantly in normal tissue, adenomas and carcinomas, but was related to disease stage. HER-3 mRNA overexpression was significantly associated with decreased time to disease progression. It was also correlated with higher median age, left colon and rectal tumour sites and lymph node involvement. CONCLUSION: We postulate that HER-3 is critically involved in colorectal tumourigenesis and its expression/phosphorylation might be of prognostic significance.

Coordinated upregulation of COX-2 and NF-kappaB is a steady feature of laryngeal carcinogenesis.

BACKGROUND/AIMS: Laryngeal cancer is the endpoint of a multistage process involving hyperplastic and dysplastic lesions, not adequately defined in their molecular aspect. Our objective was to evaluate the expression of the prostaglandin-synthesizing enzyme cyclooxygenase-2 (COX-2) and the chief transcription factor nuclear factor-kappaB (NF-kappaB) in laryngeal carcinomas and their precursors, as well as to explore any association between the two molecules. METHODS: We performed paraffin section immunohistochemistry for COX-2 and the p65 subunit of NF-kappaB, in tissues from 129 patients with tumors or premalignancies. p65 cytoplasmic and nuclear immunostaining were listed individually. RESULTS: COX-2 was positively correlated with histopathological grading from normal mucosa to carcinomas (Spearman's coefficient r(s) = 0.286, p < 0.001). No association was revealed between COX-2 expression and tumor grade. p65 immunoreactivity, both of cytoplasmic and nuclear origin, increased along the carcinogenesis course, manifesting highest expression in invasive cancer (r(s) = 0.419, p < 0.001 and r(s) = 0.241, p < 0.001, respectively). Again, tumor grade had no influence on expression. COX-2 and p65 cytoplasmic, but no nuclear, expression showed a positive correlation (r(s) = 0.352, p < 0.001). CONCLUSIONS: This study demonstrates that lesional advance in the larynx towards cancer is marked by ongoing upregulation of COX-2 and NF-kappaB. Synchronism between individual expressions may denote a regulatory role of the latter in COX-2 transactivation.