Transforming Growth Factor-ß1/Smad Signaling in Glomerulonephritis and Its Association with Progression to Chronic Kidney Disease.

INTRODUCTION: Transforming growth factor-ß1 (TGF-ß1) is a multifunctional cytokine, with diverse roles in fibrosis and inflammation, which acts through Smad signaling in renal pathology. We intended to investigate the expression of TGF-ß/Smad signaling in glomerulonephritis (GN) and to assess its role as risk factor for progression to chronic kidney disease (CKD). METHODS: We evaluated the immunohistochemical expression of TGF-ß1, phosphorylated Smad3 (pSmad3), and Smad7 semiquantitatively and quantitatively using computerized image analysis program in different compartments of 50 renal biopsies with GN, and the results were statistically analyzed with clinicopathological parameters. We also examined the associations among their expressions, the impact of their co-expression, and their role in progression to CKD. RESULTS: TGF-ß1 expression correlated positively with segmental glomerulosclerosis (p= 0.025) and creatinine level at diagnosis (p = 0.002), while pSmad3 expression with interstitial inflammation (p = 0.024). In glomerulus, concomitant expressions of high Smad7 and medium pSmad3 were observed to be correlated with renal inflammation, such as cellular crescent (p = 0.011), intense interstitial inflammation (p = 0.029), and lower serum complement (C) 3 (p = 0.028) and C4 (p = 0.029). We also reported a significant association between pSmad3 expression in glomerular endothelial cells of proliferative GN (p = 0.045) and in podocytes of nonproliferative GN (p = 0.005). Finally, on multivariate Cox-regression analysis, TGF-ß1 expression (hazard ratio = 6.078; 95% confidence interval: 1.168-31.627; p = 0.032) was emerged as independent predictor for CKD. DISCUSSION/CONCLUSION: TGF-ß1/Smad signaling is upregulated with specific characteristics in different forms of GN. TGF-ß1 expression is indicated as independent risk factor for progression to CKD, while specific co-expression pattern of pSmad3 and Smad7 in glomerulus is correlated with renal inflammation.

PAPOLA contributes to cyclin D1 mRNA alternative polyadenylation and promotes breast cancer cell proliferation.

Poly(A) polymerases add the poly(A) tail at the 3' end of nearly all eukaryotic mRNA, and are associated with proliferation and cancer. To elucidate the role of the most-studied mammalian poly(A) polymerase, poly(A) polymerase α (PAPOLA), in cancer, we assessed its expression in 221 breast cancer samples and found it to correlate strongly with the aggressive triple-negative subtype. Silencing PAPOLA in MCF-7 and MDA-MB-231 breast cancer cells reduced proliferation and anchorage-independent growth by decreasing steady-state cyclin D1 (CCND1) mRNA and protein levels. Whereas the length of the CCND1 mRNA poly(A) tail was not affected, its 3' untranslated region (3'UTR) lengthened. Overexpressing PAPOLA caused CCND1 mRNA 3'UTR shortening with a concomitant increase in the amount of corresponding transcript and protein, resulting in growth arrest in MCF-7 cells and DNA damage in HEK-293 cells. Such overexpression of PAPOLA promoted proliferation in the p53 mutant MDA-MB-231 cells. Our data suggest that PAPOLA is a possible candidate target for the control of tumor growth that is mostly relevant to triple-negative tumors, a group characterized by PAPOLA overexpression and lack of alternative targeted therapies.

IGF-IEc expression is increased in secondary compared to primary foci in neuroendocrine neoplasms.

Different Insulin-like growth factor-I (IGF-I) mRNA transcripts are produced by alternative splicing and particularly the IGF-IEc isoform has been implicated in the development and/or progression of various types of cancer. In the present study, we examined the potential role of IGF-IEc expression as a new immunohistochemical marker of aggressiveness in neuroendocrine neoplasms (NENs). We utilized immunohistochemical analysis in tissue specimens of 47 patients with NENs, to evaluate the expression of IGF-IEc (%) and Ki-67 proliferation index (%). Specimens from patients with tumors of different tissue origin, of either primary or metastatic lesions and of different grade were examined. Cytoplasmic IGF-IEc staining was found in 23 specimens of NENs or NECs: 10 pancreatic, 4 small bowel, 3 gastric, 1 lung, 1 uterine and 4 poorly differentiated of unknown primary origin. Ki-67 and IGF-IEc expression was positively correlated in all the samples studied (r=0.31, p=0.03). IGF-1Ec expression was more prevalent in specimens originating from metastatic foci with high Ki-67 compared to primary sites with low Ki-67 expression (p=0.036). These findings suggest a possible role of IGF-IEc in NEN tumorigenesis and progression to metastases that could be used as an additional new marker of a more aggressive behavior and a potential drugable target.

Clinical significance of AGE-RAGE axis in colorectal cancer: associations with glyoxalase-I, adiponectin receptor expression and prognosis.

BACKGROUND: Advanced glycation end products (AGEs) and their receptor RAGE emerge as important pathogenic contributors in colorectal carcinogenesis. However, their relationship to the detoxification enzyme Glyoxalase (GLO)-I and Adiponectin receptors (AdipoR1, AdipoR2) in colorectal carcinoma (CRC) is currently understudied. In the present study, we investigated the expression levels of the above molecules in CRC compared to adjacent non-tumoral tissue and their potential correlation with clinicopathological characteristics and patients' survival. METHODS: We analyzed the immunohistochemical expression of AGE, RAGE, GLO-1, AdipoR1 and AdipoR2 in 133 primary CRC cases, focusing on GLO-I. The tumour MSI status was further assessed in mucinous carcinomas. Western immunoblotting was employed for validation of immunohistochemical data in normal and tumoral tissues as well in three CRC cell lines. An independent set of 55 patients was also used to validate the results of univariate survival analysis regarding GLO-I. RESULTS: CRC tissue showed higher intensity of both AGE and RAGE expression compared with normal colonic mucosa which was negative for GLO-I in most cases (78 %). Western immunoblotting confirmed AGE, RAGE and GLO-I overexpression in tumoral tissue. GLO-I expression was directly related to RAGE and inversely related to AGE immunolabeling. There was a trend towards higher expression of all markers (except for RAGE) in the subgroup of mucinous carcinomas which, although of borderline significance, seemed to be more prominent for AdipoR1 and AGE. Additionally, AGE, AdipoR1 and Adipo R2 expression was related to tumor grade, whereas GLO-1 and AdipoR1 to T-category. In survival analysis, AdipoR2 and GLO-I overexpression predicted shortened survival in the entire cohort and in early stage cases, an effect which for GLO-I was reproduced in the validation cohort. Moreover, GLO-I emerged as an independent prognosticator of adverse significance in the patients' cohort. CONCLUSIONS: We herein provide novel evidence regarding the possible interactions between the components of AGE-RAGE axis, GLO-I and adiponectin receptors in CRC. AGE and AdipoR1 are possibly involved in colorectal carcinogenesis, whereas AdipoR2 and GLO-I emerged as novel independent prognostic biomarkers of adverse significance for patients with early disease stage. Further studies are warranted to extend our observations and investigate their potential therapeutic significance.

Exon 8 amplification of epidermal growth factor receptor (EGFR) in invasive breast carcinomas.

AIMS: The rate of EGFR amplification in breast cancer ranges between 0% and 15%. Recent studies have focused on the amplification status of cytosine-adenine (CA) repeats in intron 1 of the gene and correlated it with increased EGFR protein. The aim of this study was to investigate, for the first time, the significance of coding exon 8 amplification of EGFR in invasive breast cancer. METHODS AND RESULTS: We investigated, by means of real-time polymerase chain reaction (PCR), the amplification status of exon 8 of the EGFR gene in 148 paraffin-embedded tissue sections, 115 with invasive breast carcinoma and 33 controls. Immunohistochemistry was utilized to detect EGFR and human epidermal growth factor receptor 2 (HER2) expression. Univariate and multivariate statistical analyses were performed for the evaluation of our results. EGFR amplification was observed in 7.8% of the patients, and EGFR was immunodetected in 9.6%. EGFR amplification was correlated positively with EGFR expression (P < 0.0001), HER2 expression (P = 0.023), coexpression of EGFR/HER2 (P < 0.0001) and nuclear grade (P = 0.047), and inversely with ER protein expression (P = .047). CONCLUSION: It appears that amplification of the coding sequence exon 8 exhibits similar biological behaviour to amplification of the regulatory sequence in intron 1, leading to elevated levels of EGFR protein.

Differential effect of the expression of TGF-ß pathway inhibitors, Smad-7 and Ski, on invasive breast carcinomas: relation to biologic behavior.

The aim of our study was to investigate the expression of Smad-7 and Ski proteins in invasive breast carcinomas, to determine their clinicopathological value and their influence on carcinomas biologic behavior. Immunohistochemistry was applied on 150 invasive breast carcinomas to detect the expression of Smad-7 and Ski. Their correlation to clinicopathologic parameters and markers of metastasis was statistically processed using chi-squared test. Overall and disease-free survival was assessed using Kaplan-Meier test and log-rank statistics. Smad-7 was immunodetected in the cytoplasm of cancer cells in 60%, whereas Ski was immunodetected in the cytoplasm and nuclei in 44.5% and 17.6% of the cases, respectively. Smad-7 expression was positively correlated with tumor size, stage, matrix metalloproteinase (MMP)-9, and MMP-14. Cytoplasmic Ski expression was negatively associated with tumor size, stage, and lymph node status, and its nuclear expression was negatively related to histologic grade. Cytoplasmic Ski expression was associated with longer overall and disease-free survival. It appears that two negative regulators of the transforming growth factor-ß pathway, Smad-7 and Ski, behave differentially in invasive breast carcinomas. Smad-7 appears to be related with an aggressive phenotype, whereas Ski expression is related to a less aggressive behavior and positively influences patients' survival.