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The discovery of the Estrogen Receptor Beta (ERβ) in 1996 opened new perspectives in the diagnostics and therapy of different types of cancer. Here, we present a review of the present research knowledge about its role in endocrine-related cancers: breast, prostate, and thyroid, and colorectal cancers. We also discuss the reasons for the controversy of its role in carcinogenesis and why it is still not in use as a biomarker in clinical practice. Given that the diagnostics and therapy would benefit from the introduction of new biomarkers, we suggest ways to overcome the contradictions in elucidating the role of ERβ.

AIM:To investigate the significance of p 16 and O 6 -methylguanine-DNA methyltransferase (MGMT ) genes promoter hypermethylation and K-ras mutations on colorectal tumorigenesis and progression.METHODS: p 16 and MGMT methylation status was examined on 47 tumor samples, and K-ras mutational s t a t u s wa s e x a mine d o n 85 t umo r s a mple s . Fo r methylation analysis, a methylation specific PCR (MS-PCR) method was used.RESULTS: p 16 and MGMT promoter methylation was found in 51% (24/47) and 43% (20/47) of CRCs, respectively, and the K-ras mutation was found in 44% (37/85) of CRCs. Comethylation of p 16 and MGMT genes was significantly associated with lower aggressiveness of the disease within a two-year period of observation.Only 27% of patients with simultaneous p 16 and MGMT methylation showed the detectible occurrence of metastasis and/or death, compared to 67% of patients without double methylation or with no methylation (3/11 vs 22/33, P < 0.05, χ 2 -test). In addition, p 16 and MGMT comethylation showed a trend toward an association with longer survival in patients with CRCs (35.5 ± 6.0 mo vs 23.1 ± 3.2 mo, P = 0.072, Log-rank test). Progression of the disease within a two-year period was observed in 66% of patients carrying the K-ras mutation, compared to only 19% of patients with wild type K-ras (29/44 vs 7/37, P < 0.001, χ 2 -test). The presence of the K-ras mutation significantly correlated to shortened overall survival (20.0 ± 1.9 mo vs 37.0 ± 1.8 mo, P < 0.001, Logrank test). The comethylation of p 16 and MGMT genes was significantly associated with lower aggressiveness of the disease even when K-ras mutations were included in the analysis as an independent variable. CONCLUSION:Our data suggest that comethylation of promoters of p 16 and MGMT genes could have a prognostic value in patients with CRC. Specifically, concurrent methylation of both genes correlates with better prognosis.

In this study, methylation-specifi c polymerase chain reaction was used to investigate the potential prognostic signifi cance of the methylation status of p15 , p16, MGMT , and DAPK genes in 51 specimens of diffuse large B-cell lymphoma (DLBCL). Hypermethylation of p15 gene was signifi cantly more prevalent in patients without relapse ( p = 0.001) and there was a trend toward more frequent presence of p15 methylation in patients without death outcome within 5-year follow-up period ( p = 0.086) Also, there was a trend toward accumulation of p15 methylation with favorable clinicopathological parameters including: age ≤ 60 years ( p = 0.091), normal levels of lactate dehydrogenase ( p = 0.090), Eastern Cooperative Oncology Group performance status < 2 ( p = 0.095), and low/intermediate low International Prognostic Index ( p = 0.076). In the female group and group of the patients without bulky tumor mass, treated with chemotherapeutic regimens including rituximab, methylation of p15 was signifi cantly related to longer overall survival ( p = 0.036 and 0.027, respectively). Our results suggest that promoter methylation of p15 gene could have prognostic value in DLBCL patients treated with rituximab when used in combination with gender and tumor size. Clin Trans Sci 2014; Volume 7: 384-390Keywords: diffuse large B-cell lymphoma , methylation, p15 , prognosis , rituximab 385 VOLUME 7 • ISSUE 5 WWW.CTSJOURNAL.COM Krajnović et al. ■ Hypermethylation of p15 Gene in DLBCL considered positive for Bcl-2, Bcl-6, or CD10 when at least 50%, 10%, or 20% of tumor cells expressed Bcl2, Bcl6, or CD10 protein, respectively. Expression of Ki67 protein in 0-30% of tumor cells was considered as weak, in 30-60% of tumor cells as moderate, and in more than 60% of the cells as strong. All procedures were carried out with the prior informed consent of the patients and with the approval of the local Ethic Committee. Treatment consisted of CHOP/R-CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone with or without rituximab) regimen. Some patients had adjuvant radiotherapy and/or surgery, and some of them underwent autologous stem-cell transplantation. Response criteria and survival outcomes were defi ned according to the recommendation of Cheson et al. 17Analysis of methylation status of the p15 , p16 , MGMT , and DAPK genes DNA methylation patterns in the promoter CpG islands of the p15 , p16 , MGMT , and DAPK genes were determined in all of 51 samples by methylation-specifi c polymerase chain reaction (MSP) following the bisulfi te modifi cation of isolated genomic DNA, as described earlier.18 Briefl y, DNA was isolated from deparaffi ned tumor specimens using standard proteinase K, phenol/chloroform/isoamyl alcohol extraction, and ethanol precipitation.19 Two micrograms of isolated DNA were denatured by NaOH (fi nal 0.3 mol/L) at 42°C for 30 minutes and modifi ed by sodium bisulfi te (5.20-5.69 mol/L, pH 5.0, Sigma, St Louis, MO, USA) for 18 hours at 50°C . Aft er incubation, DNA was purifi ed using the DNA extraction...

Liposarcoma represents the most frequent group of soft tissue sarcomas. The group can be divided into three different classes: (1) differentiated/undifferentiated (WDLPS/DDLPS), (2) myxoid/round cell (MLPS/RCLPS) and (3) pleomorphic liposarcoma (PLS). It has become apparent that p53-p14 and Rb-p16 pathways play important roles in the pathogenesis of various sarcoma types. Molecular studies of the genes involved in these two pathways showed wide variations between the liposarcoma subtypes or even within the same subtype. We sought to examine mutational status of p53 and methylation status of p16 (INK4a) /p14 (ARF) genes in primary and recurrent liposarcoma tumors. There were twelve myxoid (12/18, 66.7 %) and six pleomorphic liposarcoma (6/18, 33.3 %) samples. Immunohistochemical analysis revealed that p53 protein was overexpressed in 3/12 MLPS (25 %) and 6/6 PLS (100 %). Mutational analysis showed that 2/11 MLPS (18.2 %) and 2/6 PLS (33.3 %) contained mutated p53 gene. On the other hand, 3/18 samples (16.7 %) had methylated p16 promoter. However, the frequencies of the p14 (ARF) gene methylation were 83.3 % (10/12) and 50 % (3/6) in myxoid and pleomorphic group, respectively. Overall, 15 out of 18 (83.3 %) samples had either p53 gene mutation or methylated p14 (ARF) promoter. The results from the current study suggest significant impact of the p14 (ARF) gene methylation on the pathogenesis and progression of myxoid and to a lesser extent pleomorphic liposarcoma. Despite the limited number of samples, our study points to necessity of further investigation of p53-p14 and Rb-p16 pathways in liposarcoma.