Adem Deligonul

XRCC1 Gene Polymorphisms and Risk of Lung Cancer in Turkish Patients

Abstract Polymorphisms in the X-ray repair cross complementing 1 (XRCC1) gene have been found to be associated with susceptibility to various types of cancers. We investigated the association between the XRCC1 gene Arg399Gln polymorphism and the susceptibility to lung cancer in Turkish patients. To determine the association of this polymorphism with the risk of lung cancer in Turkish patients, a hospital-based case-control study was designed, involving 67 patients with lung cancer and 60 control subjects with no cancer history who were matched for age and gender. XRCC1 genotypes (Arg/Arg, Arg/Gln, and Gln/Gln) were determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis on genomic DNA. No statistically significant relationship was determined between the lung cancer and control groups (p>0.05). Among the patients, 61% were Arg/Arg, 28% were Arg/Gln, and 11% were Gln/Gln. Among the controls, 50% were Arg/Arg, 38% were Arg/Gln, and 12% were Gln/Gln. There was no difference in the distribution of XRCC1 genotypes or the frequencies of the Arg (75% versus 69%) and Gln (25% versus 31%) alleles between the lung cancer patients and controls. Our results suggest that the XRCC1 gene Arg399Gln polymorphism is not associated with an increased risk for the development of lung cancer in Turkish patients.

Prognostic Significance of Human Epidermal Receptor (HER)- 3 Immunohistochemical Expression in Patients with Metastatic Breast Cancer

BACKGROUND Previous reports have shown that human epidermal receptor (HER)-3 overexpression may be associated with poor prognosis in patients with breast cancer, but results have been conflicting. In this study, we sought to investigate the prognostic significance of HER-3 immunohistochemical expression in patients with metastatic breast cancer. METHODS We retrospectively analyzed HER-3 immunohistochemical expression profiles in 45 paraffin-embedded specimens from patients who had been treated between 1996 and 2006 in the Department of Oncology of the Uludag University School of Medicine, Bursa, Turkey. Membranous or cytoplasmic dominant expression patterns of HER-3 were analyzed using the Rajkumar score and a cytoplasmic 4-point scoring system, respectively. Progression-free survival (PFS) and overall survival (OS) served as the main outcome measures. RESULTS The median PFS in the study participants was 9 months (interquartile range: 4.5-13 months), whereas the median OS was 20 months (interquartile range: 7.5-28 months). Categorization of the patient population according to HER-3 positive immunohistochemical expression did not reveal any statistically significant difference in terms of both PFS (p=0.70) and OS (p=0.81). The results of multivariable Cox regression analysis indicated that tumor size was the only independent predictor of PFS, whereas estrogen and progesterone receptor status was independently associated with OS. CONCLUSIONS HER-3 immunohistochemical expression did not correlate with outcomes in Turkish patients with metastatic breast cancer. Although our results suggest that HER-3 expression in cancer specimens is not of prognostic significance, further prospective studies are warranted to confirm these results.

Malignant melanoma of the stomach in an elderly patient.

To the Editor, Malignant melanoma (MM) is a highly aggressive disease that originates from typical sites where the melanocytes can be usually found (skin, eyes, meninges, and anal region) (1,2). MM can attack any part of the gastrointestinal (GI) tract, and this event is mainly caused by metastatic spread from primary cutaneous lesions. However, there is a portion of GI melanomas without any documented evidence of a primary lesion in the skin or elsewhere, even after thorough examination. In such cases, involved organ of the digestive system is considered the primary site of MM (2,3).

Investigation of FGFR4 (Gly388Arg) Gene Polymorphism in Primary Lung Cancer Patients

Abstract Several studies have shown relationships between predisposition to various types of cancer and polymorphisms of the fibroblast growth factor receptor 4 (FGFR4) gene. In the present study, researchers investigated the relationship between primary lung cancer and (PLC) FGFR4 Gly388Arg polymorphism in regard to tendency, histopathologic sub-type, early onset, and metastatic status. The present study included 124 PLC patients and 100 healthy controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to identify gene polymorphism of FGFR4 Gly388Arg. Statistical significance was considered when p < 0.05, and a statistically significant difference was not found in FGFR-4 polymorphism between the patient group and control group in regard to tendency, histopathologic sub-type, early onset, and metastatic status (p> 0.05). The findings in this study demonstrated that there was no relationship between polymorphism of FGFR4 Gly388Arg gene and PLC. However, these results should be confirmed in larger studies and in specific histopathological sub-types of PLC.

Lack of prognostic significance of adiponectin immunohistochemical expression in patients with triple-negative breast cancer.

Introduction Triple-negative breast cancers (TNBCs) – which lack the expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) – have no established markers that can be used for prognostic stratification. As adiponectin has been previously implicated in a more aggressive phenotype of primary breast cancer, we explored the relation between adiponectin immunohistochemical expression and prognosis in TNBCs. Material and methods Immunohistochemical staining for adiponectin was performed in 38 TNBC patients. Disease-free survival (DFS) and overall survival (OS) served as the main outcome measures. Results Of the 38 TNBC patients, 18 (47%) had negative and 20 (53%) positive adiponectin immunohistochemical expression. We did not find any significant association between adiponectin immunohistochemical expression and the baseline characteristics. In addition, there were no associations between adiponectin immunohistochemical expression and prognosis. Conclusions Although our results suggest that adiponectin immunohistochemical expression is not of prognostic significance in TNBCs, further studies are warranted to determine the role of this adipokine in breast cancer biology.

Smoking habits are an independent prognostic factor in patients with lung cancer.

The role of tobacco in the pathogenesis of lung cancer (LC) has been clearly established. Based on the epidemiological evidence that smoking may influence LC progression, we investigated the idea that smoking behavior could be associated with overall survival (OS) in this group of patients.

Enhancer of zeste homologue 2 (EZH2) expression in synovial sarcomas as a promising indicator of prognosis

Synovial sarcoma (SS) is a type of soft-tissue sarcoma, often linked to poor survival. Although overexpression of enhancer of zeste homologue 2 (EZH2) has been associated with poor prognosis in different tumors, a few studies investigated this link in SS. Here, we analyzed the relationship between EZH2 expression and prognostic factors in SS. We included 29 patients with SS. Immunostaining of EZH2 was performed with (D2C9) XPTM Rabbit mAb antibody, and the results were classified as low EZH2 expression (negative or weak expression) and high EZH2 expression category (moderate or strong expression). Analysis of survival in relation to prognostic factors was performed with Kaplan-Meier survival curves and Cox proportional hazard regression analysis. Our sample included 19/29 female and 10/29 male patients, with age range 16-63 years. The tumor diameter ranged from 2 to 15 cm. Necrosis was observed in 15/29 cases. Sixteen cases had >10 mitoses per 50 high-power fields (HPFs). Out of 29 cases, 14 showed low and 15 had high EZH2 expression. Statistically significant results were obtained for the association between the presence of metastasis and necrosis (p = 0.042), high EZH2 expression and distant metastasis (p = 0.018), high EZH2 expression and necrosis (p = 0.016), and high EZH2 expression and the tumor size >5 cm versus tumor size ≤5 cm (p = 0.014). Patients with all of the following: the tumor size ≤5 cm, low EZH2 expression, and without necrosis and distant metastasis had significantly longer survival time. Our results are consistent with previous studies, suggesting that EZH2 overexpression is an indicator of poor prognosis in SS.

Efficacy of Sunitinib in Patients with Imatinib-Resistant Gastrointestinal Stromal Tumors

Aim: In this study, the efficacy of sunitinib in patients with imatinib-resis - tant gastrointestinal stromal tumors (GISTs) was investigated. Material and Method: A total of 11 imatinib-resistant GIST patients who have sufficient information about their medical treatment and outcome were retrospectively analyzed. Results: Partial response was observed in only two patients, and five patients achieved stable disease. Progression free survival and overall time was 8.8 months and 12 months, respectively. Sunitinib was relatively well tolerated. Almost all patients experienced one or more treatment-relat- ed adverse event. Discussion: Based on our limited experience, we concluded that sunitinib is reasonable treatment option for patients with imatinib- resistant GIST.

Molecular Markers for Patients with Thymic Malignancies: not Feasible at Present?

BACKGROUND Thymomas and thymic carcinomas are rare malignancies and devising clinically effective molecular targeted therapies is a major clinical challenge. The aim of the study was to analyze BLC2 and vascular endothelial growth factor receptor (VEGFR) expression and KRAS and EGFR mutational status and to correlate them with the clinical characteristics of patients with thymomas and thymic carcinomas. MATERIALS AND METHODS A total of 62 patients (mean age: 50.4 ± 13.2 years) with thymomas and thymic carcinomas were enrolled. The expression of BLC2 and VEGFR in tumor cells and normal tissues was evaluated by RT-PCR. The mutational status of the KRAS and EGFR genes was investigated by PCR with sequence specific primers. RESULTS The BLC2 and VEGFR expression levels did not differ significantly between tumor and normal tissues. Moreover, there were no clearly pathogenic mutations in KRAS or EGFR genes in any tumor. None of the molecular markers were significantly related to clinical outcomes. CONCLUSIONS Changes in levels of expression of BLC2 and VEGFR do not appear to be involved in thymic tumorigenesis. Moreover, our data suggest that KRAS and EGFR mutations do not play a major role in the pathogenesis of thymomas and thymic carcinomas.

The SOCS-1 -1478CA/del Polymorphism is not Associated with Colorectal Cancer or Age at Onset in Turkish Subjects

BACKGROUND Suppressor of cytokine signaling (SOCS)-1 acts as a key regulator of many cytokine signaling pathways and its abnormal expression has been identified in several human malignancies, suggesting potential roles in carcinogenesis. The aim of this study was to investigate any association between the functional SOCS- 1 -1478CA>del polymorphism and colorectal cancer (CC) as well as age at onset in a Turkish clinical sample. MATERIALS AND METHODS A total of 122 subjects were enrolled in this case-control study (70 CC cases and 52 controls). The SOCS-1 -1478CA>del polymorphism was genotyped using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS The odds ratio of the del allele for CC relative to the CA allele was not significantly different between the groups (OR=0.71, 95% CI=0.41-1.22, p=0.27). This result did not change after adjustment for age and sex on multivariable regression analysis (OR=0.84, 95% CI=0.59-1.34, p=0.53). When the SOCS-1 -1478CA>del polymorphism was analyzed among CC patients in relation to the age at disease onset, we found no significant differences between subjects with the del/del, CA/del, and CA/CA genotypes. CONCLUSIONS The results of our study did not point towards a major role of the SOCS-1 -1478CA>del polymorphism in the pathogenesis of CC in Turkish subjects.