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Aim: Gastric cancer is among the most common causes of cancer-related death worldwide. Since microRNAs (miRNAs) represent an emerging field of cancer research, there is an increasing interest regarding the miRNA responses to environmental and lifestyle exposures. The aim of our study was to analyze whether social status, living conditions and lifestyle behaviours, such as cigarette smoking and alcohol consumption, are associated with specific miRNA expression patterns of gastric adenocarcinoma., Materials and Methods: Thirty-nine formalin-fixed paraffin-embedded primary gastric adenocarcinoma and nine non-tumourous samples were analyzed by real-time polymerase chain reaction. The expression levels of miR-21, miR-34a, miR-93, miR-143, miR-203, miR-205, miR-223 were compared in gastric adenocarcinoma samples of patients with different demographical characteristics, social status, drinking and smoking habits., Results: Overexpression of miR-21, miR-143 and underexpression of miR-34a were observed in gastric cancer samples relative to the controls. Elevated expression of miR-21 was detected in patients with low social status. Smokers showed higher expression of miR-21 and lower expression of miR-143. Up-regulation of miR-203, miR-205 and miR-223 was identified in patients with regular alcohol consumption. Patients living in an urban environment had elevated expression levels of miR-143 and miR-34a., Discussion: Differential miRNA expression patterns of gastric adenocarcinoma of the same histopathology from a small geographic region's population show homogenous correlations with the existence of common risk factors.

Background: Although the majority of endometrial cancer (EC) patients can be cured by surgery, unexpected recurrent disease may also occur in early stage patients. In the present study, whether or not the analysis of multiple biopathological parameters might lead to more accurate predictions of the clinical outcome of EC patients with long-term follow-up (FU) was investigated., Patients and Methods: Estrogen and progesterone receptor (ER and PgR) positivity and HER2 overexpression by immunohistochemistry were evaluated. The peritoneal washings (PWs) were analyzed by cytology and immunocytochemistry employing AR-3 and B72.3 monoclonal antibodies., Results: The patients with positive PW and HER2 positive tumors showed shorter overall survival compared to those bearing HER2 negative tumors (p =0.004). HER2 overexpression also influenced the patient outcome in the group with tumors lacking PgR (p = 0.004). At multivariate analysis PgR and HER2 overexpression emerged as independent prognostic factors., Conclusion: The combined analysis of these biopathological markers could provide useful information for the selection of patients to be enrolled in innovative therapeutic strategies.

Background: Breast cancer is the most common cancer among women, with variable outcomes, justifying a continuous search for new parameters to predict accurate prognosis and indicate suitable adjuvant therapy for patients., Materials and Methods: Fourty-four stage I-III breast cancer specimens were investigated immunohistochemically for the expression of cyclooxygenase-2 enzyme (COX-2), hormone receptors, tumor suppressor gene p53, oncogene HER2 and proliferation marker Ki-67. Additionally, twelve specimens were also investigated for the presence of the phosphorylated extracellular signal-regulated kinase (pERK)., Results: It was demonstrated that expressions of biological markers were related to each other (ER to p53 and Ki-67, COX-2 to ER, PgR, Ki-67 and p53, Ki-67 to p53 and PgR, p53 to PgR)., Conclusion: Our data indicate that concomitant immunohistochemical evaluation of cyclooxygenase-2, hormone receptors, p53 and Ki-67 may be of clinical value in determining an accurate prognosis.

Background: The UNI antigen (Ag) is a 120 kDa sialoglycoprotein which has been primarily found in human undifferentiated CD3dim thymocytes and leukemic T-cell lines, but subsequently also detected in solid tumors. We studied the expression of this Ag in a panel of normal and pathological breast tissues., Materials and Methods: Analysis of UN1 Ag expression on tissue specimens was performed by immunohistochemistry and Western blotting., Results: No Ag expression was found in 14 sections of normal tissue and 10 sections of benign nonproliferative lesions. Progressively increasing levels of UN1 Ag expression were found in fibroadenomas (24 positive out of 27 cases), proliferative lesions (9 cases), in situ (17 cases) and invasive carcinomas (56 cases). Finally, the highest expression was observed in 10 metastatic lesions., Conclusion: These data suggest that UN1 Ag is a promising marker of potential value for immunophenotyping studies and therapeutic applications in breast diseases.

The present study analyzed the combined immunostaining for proliferating cell nuclear antigen (PCNA) and epidermal growth factor receptor (EGFR) with the aim of obtaining an objective method for the evaluation of the growth fraction in human glial tumors. A retrospective study was undertaken on 157 gliomas employing MoAb PC10 and MoAb 108, recognizing a 36 Kd nuclear protein associated with the cell cycle and the extracellular domain of the EGFR, respectively. The results of this immunohistochemical analysis showed that the rate of PCNA positive cell is directly associated to EGFR expression and significantly (P < 0.0001) correlates with tumor morphological grading, this was also the case in patients submitted to multiple surgical treatments for recurrent tumors. PCNA and/or EGFR are expressed by a minority of low grade astrocytoma, while anaplastic astrocytoma and glioblastoma displayed an intense immunoreactivity for the two antigens in more than 85% of tested cases. These findings indicate that the combined evaluation of PCNA and EGFR could allow a more definite biopathological grading of neuroepithelial brain tumours.

The established non papillary human renal carcinoma cell line (RCC) KJ29 was submitted to a multiparametric characterization to evaluate its potential use for in vitro and in vivo studies. The cell line grows in vitro as monolayer as well as cell suspension. Cytogenetic analysis has shown a modal chromosome number of 50 with some marker chromosomes, including rearrangements of chromosomes 1 and 3. The antigenic phenotype is characterized by co-expression of cytokeratin and vimentin, as well as expression of urothelium differentiation antigens, low levels of class II MHC antigens and no class I antigens. A differential expression of the VLA-3 integrin heterodimer has been detected between the adherent and non adherent cell population. The cell line which is highly tumorigenic in athymic mice displays expression of erb B-2 and c-met oncogenes and high expression of cell-cycle related and Ha-ras 1 genes.

The antiproliferative and antineoplastic effects of the interferons may result, at least in part, from changes in the expression and quantity of specific oncogene products. To explore this hypothesis we have determined the effect of interferons, including recombinant leukocyte (IFN-alpha), fibroblast (IFN-beta) and immune (IFN-gamma), on expression of the Ha-ras proto-oncogene in the human melanoma cell line Colo 38. While concentrations of up to 1000 U/ml of either IFN-alpha or IFN-beta did not affect the total amounts of Ha-ras products, IFN-gamma at concentrations ranging from 20 to 200 U/ml caused a dose- and time-dependent (48-96 hr) reduction (approximately 40%) in the accumulation of Ha-ras-1 mRNA and in the synthesis of the specific protein products. Downregulation of this proto-oncogene occurs prior to the antiproliferative effects of IFN-gamma and parallels similar IFN-gamma mediated changes in the expression of certain melanoma associated antigens. The present findings indicate that this experimental model may prove valuable in determining whether a direct relationship exists between the antiproliferative activity of specific interferons and the downregulation of oncogene expression.

The ability of interferons to modulate the antigenic phenotype of tumor cells may involve alterations in the transcription, translation, membrane expression and shedding of Major Histocompatibility Complex (MHC) and Tumor Associated Antigens (TAAs). In the present study we have investigated possible mechanisms by which recombinant human interferons, IFN-alpha, -beta and -gamma, alter the antigenic profile of long- and short-term human melanoma cultures. IFN-alpha and -beta induced similar changes in the synthesis, expression and shedding of two TAAs, a HMW-MAA and a Cyt-MAA, in the established melanoma cell line Colo 38, whereas IFN-gamma exerted a differential effect on these melanoma associated antigens. Moreover, IFN-gamma was relatively more effective than IFN-alpha or -beta in upregulating the synthesis, expression and shedding of class I MHC antigens. At the same time a dramatic differential effect of the interferons was observed with class II MHC antigens. IFN-alpha or -beta induced a modest increase in the synthesis and expression of these antigens, whereas IFN-gamma was greater than 3-fold more active in inducing the synthesis and expression of DR/DP antigens and greater than 4- and greater than 10-fold more effective in increasing the synthesis and expression, respectively, of DQ antigens. Analysis of the levels of cytoplasmic mRNA for the DR-alpha and DQ-beta genes indicated no significant difference between IFN-alpha, beta or -gamma treated cells suggesting that IFN-gamma enhancement of the synthesis of DR and DQ antigens may occur at a posttranscriptional level. In the case of a newly established human melanoma cell line (MG-3) IFN-gamma enhanced the synthesis but not the expression of DR antigens and did not alter either the synthesis or expression of DQ antigens. Our studies indicate that the effects of interferons on the antigenic phenotype of melanoma cells will vary depending on the type of interferon employed, the antigen monitored and the target cell studied. In addition, it is also apparent that some of the biosynthetic steps involved in regulating the synthesis, expression and shedding of antigens may be coordinately regulated in some melanoma cells, whereas these processes may be under independent control in other melanoma populations.

The DNA methylation pattern of the human Ha-ras-1 oncogene and the levels of specific mRNA have been analysed in established tumor cell lines and in surgical biopsies. In long-term cultures, the Ha-ras-1 gene is hypomethylated at its 5' end and highly methylated at its 3' portion. The GCGC sites at the 5' end have been shown to become methylated only when E. Coli HhaI methylase is added to isolated DNA, while they remain unmethylated when the enzyme is added to chromatin. These data indicate that the 5' portion of this protooncogene is maintained physiologically unmethylated, possibly because it is necessary for gene transcription. Along the same line of evidence, when levels of mRNA and methylation of the gene were comparatively analysed in breast tumors and autologous normal mammary tissue, no appreciable differences in the degree of methylation were found despite significant differences in mRNA content. These findings show that the levels of Ha-ras- mRNA are independent of the DNA methylation state.

Modulation of class I and II MHC antigen expression by interferons has been the focus of considerable attention because the regulation of these molecules serves as a useful model system to study factors exerting transcriptional control of gene expression and because of the relevance of these molecules to expression of the neoplastic phenotype. While our knowledge of the molecular mechanisms regulating the ability of interferon to mediate enhancement of MHC genes has increased, this information is primarily based on studies employing established cell lines, and it remains to be determined whether similar controls are also exerted in short term cultured cell lines. In this short review, we have discussed the structural organization of the 5' flanking regions of the MHC genes, with special emphasis on class II genes, and the implications of these data for the transcriptional regulation of these and of other interferon inducible genes. Present evidence indicates the existence of at least four conserved upstream sequences which are shared by interferon responsive genes and which appear to be involved in the transcriptional control of these genes. The pattern of metabolic requirements for IFN-alpha and IFN-beta versus IFN-gamma upregulation of the class I and II MHC genes suggests that the regulation of gene expression by IFN-gamma requires unique regulatory molecules, i.e. newly synthesized proteins, which are not required by IFN-alpha and IFN-beta treated cells. These putative mediators of gene expression are likely to be shared by many of the biochemical induction pathways involved in the regulation of genes which exhibit interferon responsive sequences. However, in addition to common regulatory signals, other specific pathways and possibly additional regulatory sequences, are also required to account for locus--or subunit-specific patterns of antigenic modulation. Future studies are required, including those employing short term tumor cell cultures, to precisely define the molecular details of gene regulation of class I and II MHC genes, as well as other interferon--responsive--genes, by interferons. These investigations will not only prove valuable on a fundamental scientific level, but they will also be crucial for the more effective application of interferons in clinical oncology.