Somatostatin Receptor 2 and 5 Expressions in Gastroenteropancreatic Neuroendocrine Tumors in Turkey

Yerci, Omer,Sehitoglu, Ibrahim,Ugras, Nesrin,Cubukcu, Erdem,Yuce, Suleyman,Bedir, Recep,Cure, Erkan Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.10

Background: Gastroenteropancreatic neuroendocrine tumors (GNs) are slow growing and although their incidence has increased in recent years, they are relatively rarely seen. Somatostatin analogues are used in the treatment of GNs that express somatostatin receptor (SR). We aimed to investigate the expression of SR2 and SR5 in GNs. Materials and Methods: In this study the expression of SR2 and SR5 was investigated immunohistochemically in 49 cases (26 males, 23 females) diagnosed and graded with GN according to the World Health Organization classification 2010. Results: The percentage of SR2 staining was 91.0% in grade 1, 82.8% in grade 2 and 100% in grade 3. On the other hand, the percentage of SR5 staining was 81.8% % in grade 1, 60.0% in grade 2 and 0% in grade 3. According to the tumor localization, the percentages of SR2 expression were as follows: pancreas 85.7%, stomach 100%, small bowel 70%, appendix 85.7% and rectum 100%. The percentages of SR5 expression were: pancreas 61,9%, stomach 37.5%, small bowel 70%, appendix 71.5% and rectum 66.6%. There was a significant negative correlation between ki67 percentage and SR5 expression (r=-0.341, p=0.016). Conclusions: In this study, GNs were found to highly express SR2 and SR5. Although the expression of SR2 and SR5 changed according to tumor localization, the expression of SR2 was higher than the expression of SR5 in GN. There was a significant negative correlation between ki67 and SR5. Accordingly, SR5 may be a prognostic indicator of GN.

Association of Adiponectin Receptor (Adipo-R1/-R2) Expression and Colorectal Cancer

Ayyildiz, Talat,Dolar, Enver,Ugras, Nesrin,Adim, Saduman Balaban,Yerci, Omer Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Introduction: Human adiponectin (ApN) is a 30 kDa glycoprotein of 244-amino acids which is extensively produced by adipocytes. ApN acts via two receptors, namely adiponectin receptor-1 (Adipo-R1) and adiponectin receptor-2 (Adipo-R2). Studies have shown the presence of Adipo-R1 and Adipo-R2 expression immunohistochemically in human colorectal cancers (CRCs). However, only a few studies exist which investigated effects of adiponectin receptor expression on CRC characteristics. Objectives: In the present study, we aimed to explore Adipo-R1/-R2 expression in human colorectal cancers and any association with clinicopathological characteristics and survival. Materials and Methods: The study enrolled 58 colorectal cancer patients with tumor resection and a control group of 30 subjects with normal colon mucosa. Results: Positivity for Adipo-R1/-R2 expression was significantly more common in the control group in comparison to the patient group (both p<0.001). There was no significant association between Adipo-R1/-R2 expression and clinicopathological characteristics including age, sex tumor location, pTNM stage, Duke's stage, metastasis, histological differentiation, perineural invasion, venous invasion sex, lymphatic invasion, cancer-related mortality, tumor size and recurrence. Adipo- R1/-R2 positivity was also not significantly linked to progression-free or overall survival [p values (0.871, 0.758) and (0.274, 0.232), respectively]. Conclusions: Although significantly reduced Adipo-R1/-R2 expression was found in colorectal cancer patients, it had no influence on survival.

Lack of Prognostic Significance of SOCS-1 Expression in Colorectal Adenocarcinomas

Ayyildiz, Talat,Dolar, Enver,Adim, Saduman Balaban,Eminler, Ahmet Tarik,Yerci, Omer Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

Introduction: Recent studies have indicated that down-regulation of the suppressor of cytokine signaling-1 (SOCS-1) gene results in tumor formation and that SOCS-1 acts as a tumor suppressor gene. SOCS-1 has been also suggested to function as a tumor suppressor with colorectal cancer. Objectives: In the present study, we aimed to determine the association of SOCS-1 expression in colorectal cancer tissues with clinicopathologic characteristics immunohistochemically and also to identify its prognostic significance. Materials and Methods: SOCS-1 expression was studied immunohistochemically in 67 patients diagnosed with resected colorectal carcinomas and 30 control subjects. Results: SOCS-1 expression was found in 46.3% of tumor tissues and 46.7% of the control group. Statistical analyses did not establish any significant association between SOCS-1 expression and clinicopathologic characteristics. Also, no significant association with SOCS-1 expression was found using progression-free survival and overall survival analyses (p=0.326 and p=0.360, respectively). Conclusions: Our results show that SOCS-1 has no prognostic significance in colorectal cancer.

Lack of any Prognostic Relationship between Adiponectin Receptor (Adipo R1/R2) Expression for Early/Advanced Stage Gastric Cancer

Ayyildiz, Talat,Dolar, Enver,Ugras, Nesrin,Dizdar, Oguzhan Sitki,Adim, Saduman Balaban,Yerci, Omer Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.11

Introduction: Adiponectin (ApN) is a complement C1q-related protein, mainly secreted from adipose tissue, that signals through ApN receptor1 (Adipo-R1) and ApN receptor 2 (Adipo-R2). Low serum ApN concentrations are associated with obesity-related malignancies. However, there are very few studies on any prognostic role of ApN receptors in gastric cancer. Objectives: The aim of this study is to investigate the relationship between AdipoR1/R2 expression and early/advanced stage gastric cancer in terms of clinicopathologic characteristics and survival. Materials and Methods: Eighteen patients with early and 39 with advanced stage gastric cancer who underwent surgical gastric resection were included in this study. Results: Adipo-R1 expression was low in 2 of the 18 patients with early stage gastric cancer (11.1%), while 4 had low Adipo-R2 expression (22.2%). In those with advanced stage gastric cancer, 7 of 39 had low Adipo-R1 expression (17.9%) and 16 had low Adipo-R2 expression (41%). Adipo-R2 expression was significantly higher (p=0.011) in moderately differentiated tumors when compared to well-differentiated tumors. While there was nearly a statistically significant relationship between TNM stage (T, tumor size; N, regional lymph node; M, whether distant metastases exist) and Adipo-R2 expression (p=0.054), there was no relationship between Adipo-R1/-R2 expression with tumor stage and survival. Conclusion: Adipo-R1/-R2 expression has no prognostic significance of in early/advanced stage gastric cancer.

Adipo-R1 and Adipo-R2 Expression in Colorectal Adenomas and Carcinomas

Ayyildiz, Talat,Dolar, Enver,Ugras, Nesrin,Eminler, Ahmet Tarik,Erturk, Banu,Adim, Saduman Balaban,Yerci, Omer Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.1

Background: Human adiponectin (ApN), a 30 kDa glycoprotein of 244-amino acids which is predominantly produced by adipocytes, exerts its effects via two receptors, namely adiponectin receptor-1 (adipo-R1) and adiponectin receptor-2 (adipo-R2) with differential binding affinity to globular adiponectin. Adiponectin receptor expression has been studied in several cancer tissues. However, there are no studies of colorectal adenomas which are considered to be precursors for colorectal carcinoma (CRC). Objectives: In the present study, the expression of adipo-R1 and adipo-R2 was investigated immunohistochemically in colorectal adenomas and colorectal carcinoma tissues in an attempt to determine associations with these tumors. Materials and Methods: The study enrolled 50 CRC patients with tumor resection and 82 patients who were diagnosed with adenomatous polyps, classified as negative for neoplasia, low-grade dysplasia (L-GD) or high- grade dysplasia (H-GD). Results: Expression of both adipo-R1 and adipo-R2 was found to be significantly lower in the CRCs than in colorectal adenomas (tubular and tubulovillous, p=0.009 and p<0.001, respectively). Adipo-R1 and adipo-R2 expression was also significantly lower in the CRC group when compared with the groups of patients with low grade dysplasia, high-grade dysplasia or no neoplasia (p=0.012 and p<0.001, respectively). In addition, it was observed that adipo-R2 expression was generally positive in the non-neoplastic group irrespective of the adipo-R2 expression. In the L-GD, H-GD and CRC groups, the adipo-R2 result was positive whenever adipo-R1 result was positive but some patients with negative adipo-R1 had positive adipo-R2 (p<0.001, p=0.004, p<0.001, respectively). Conclusions: This study indicated that ApN may play a role in the progression of colorectal adenomatous polyps to carcinoma through actions on adipo-R1 and adipo-R2 receptors.