Özgür Ekinci

REduCtIon of poStSuRgICAl AdHESIonS In A RAt modEl: A CompARAtIvE Study

BACKGROUND: Adhesion formation after peritoneal surgery is a major cause of postoperative bowel obstruction, infertility, and chronic pelvic pain. In this study, we compared the possible individual effects of phosphatidylcholine (PC), Seprafilm® II, and tissue plasminogen activator (t-PA) and the combined effects of phosphatidylcholine and t-PA on postoperative adhesion formation in a rat surgical model. MATERIALS AND METHODS: A total of 50 Wistar male rats underwent median laparotomy and standardized abrasion of the visceral and parietal peritoneum. phosphatidylcholine, Seprafilm II, and t-PA alone and phosphatidylcholine and t-PA in combination were applied intraperitoneally at the end of the surgical procedure. Seven days after surgery, a relaparotomy was performed for adhesion grading and histopathological examination. RESULTS: A comparison of adhesion stages demonstrated a significant difference between the control group and the study groups (p<0.001). The adhesion grade of the combined treatment group was statistically different from that of the other groups (p<0.05). In the t-PA group and the combined group, six and two rats, respectively, developed hematomas locally on the cecum. CONCLUSIONS: PC, t-PA, and Seprafilm II used individually reduced the adhesion grade. The t-PA and phosphatidylcholine combination was most effective in reducing adhesion formation. On the other hand, usage of t-PA alone or in combination may increase risk of bleeding. More detailed studies are needed, and future studies on the efficacy of a material for decreasing adhesion formation should include a comparison of several control materials in the same model.

Survivin expression in pre-invasive lesions and non-small cell lung carcinoma

Survivin is an inhibitor of apoptosis protein, which is overexpressed in many carcinomas, including lung carcinoma. The aim of this immunohistochemical study was to investigate the role of survivin in the early steps of lung carcinogenesis and non-small cell lung carcinomas (NSCLC), and its relationship with expression of p53 protein, a tumor suppressor gene involved in cell cycle control. In the normal bronchial epithelium, low-grade atypical adenomatous hyperplasia (AAH) and non-neoplastic lung parenchyma adjacent to tumor, survivin was found completely negative. Expression of survivin was detected in the areas of squamous metaplasia and dysplasia as well as high-grade AAH lesions adjacent to tumor. Survivin was expressed in 50 (64%) and p53 in 41 (53%) NSCLC. Survivin expression was significantly correlated with lymph node metastasis (p=0.02). There was no correlation between survivin and p53 expression. The patients with expression of survivin had significantly worse prognosis (Log-rank test, p=0.003). Multivariate Cox regression analysis showed TNM stage (p<0.001) and survivin expression (p=0.003) as independent prognostic indicators. In conclusion, survivin expression might be an early step in lung carcinogenesis. Survivin expression might also be used as a prognostic indicator predicting the worse outcome in NSCLC, and might be a novel target for the treatment of patients with preinvasive lesions of lung and NSCLC.

Nodular regenerative hyperplasia and focal nodular hyperplasia of the liver mimicking hepatic metastasis in children with solid tumors and a review of literature.

Nodular regenerative hyperplasia (NRH) and focal nodular hyperplasia (FNH) of the liver rarely occur in children after completion of tumor therapy. These lesions mimic hepatic metastasis and they must be distinguished from metastatic lesions. The authors present 2 children, one with NRH and one with FNH, after undergoing antineoplastic therapy for non-hepatic childhood solid tumors and discuss their patients in the context of the literature.

Methylphenidate has dose-dependent negative effects on rat spermatogenesis: decreased round spermatids and testicular weight and increased p53 expression and apoptosis:

In the present study, we aimed to evaluate the possible effects of methylphenidate on rat testes. Forty-two Wistar rats were randomly distributed into three experimental groups of 14 rats each. For 90 days, each group via gavage received the following: group 1 = tap water (control group), group 2 = 5 mg/kg/day of ritalin (methylphenidate, MPH), and group 3 = 10 mg/kg/day of ritalin. After sacrificing the animals, the body weights as well as the absolute and relative testicular weights were measured. Testes were sampled, fixed, and processed and, by histopathological examination, quantitative morphometric analysis of Sertoli cells, spermatocytes, and spermatids was performed in stages II, V, and XII. Immunohistochemistry was performed for transforming growth factor (TGF)-β1 and p53, and the apoptotic index was assessed through the TUNEL method. Group 2 had a reduction of round spermatids in stage II. Group 3 had reduction in both stage II and stage V spermatids, as well as lower testicular weight. The p53 expression was increased in group 3. In groups 2 and 3, the TGF-β1 expression was reduced and the apoptotic index by TUNEL was increased. Body weights remained stable on either group. Our results showed that methylphenidate might negatively affect spermatogenesis not only by reducing testicular weight and amount of round spermatids but also by increasing apoptotic death and p53 activation. The findings of the study, however, must be cautiously interpreted.

Prognostic Significance of Expression of CD133 and Ki-67 in Gastric Cancer

CD133 is one of the most important stem cell markers in solid cancers and Ki-67 is a marker that reflects cell proliferation. The relationships between the expression of CD133 and Ki-67 and prognosis in gastric carcinoma are unknown and need exploring. We examined 50 gastric cancer patients retrospectively in the Radiation Oncology Department of the Faculty of Medicine, Gazi University. CD133 and Ki-67 expression was examined using immunohistochemical staining. The survival rate in patients with CD133 positive expression was significantly worse than that in the patients with negative expression (p=0.04). Expression of CD133 had a positive correlation with that of Ki-67 (r=0.350; p=0.014). Multivariate analysis revealed that the expression of CD133 was an independent prognostic factor in gastric cancer (p=0.02). Conclusion, expression of CD133 may be a useful prognostic marker in gastric cancer.

Discordances in HER2 status between primary gastric cancer and corresponding metastatic sites

OBJECTIVE Determination of human epidermal growth factor receptor-2 status in advanced gastric cancer is important in clinical decision making. In the trastuzumab for GC trial, trastuzumab-based therapy demonstrated a significant overall survival benefit in patients with human epidermal growth factor receptor-2-positive advanced gastric cancer. Human epidermal growth factor receptor-2 discordance in gastric cancer primary and its metastases has been long debated. The aim of the study was to evaluate the rate of human epidermal growth factor receptor-2 discordance and its effect on treatment decisions in advanced gastric cancer. METHODS A total of 74 patients with advanced gastric cancer were included in the study. Both immunohistochemical staining and dual-color silver in situ hybridization were performed in all patients to evaluate the human epidermal growth factor receptor-2 status of the primary lesion and paired metastasis. RESULTS The assessment of human epidermal growth factor receptor-2 status with the immunohistochemical staining method and dual-color silver in situ hybridization revealed a discordance rate of 9.5 and 16.2%, respectively. However, this discordance was clinically meaningful in only one patient leading to a change in treatment decision. While this patient had a human epidermal growth factor receptor-2-negative status in primary tumor (immunohistochemical = 0, dual-color silver in situ hybridization = negative), the human epidermal growth factor receptor-2 status was positive for liver metastasis (immunohistochemical = 2+, dual-color silver in situ hybridization = positive). Trastuzumab was added to the chemotherapy regimen. CONCLUSIONS In this study, we found a higher rate of human epidermal growth factor receptor-2 discordance between primary gastric tumor and metastatic lesions compared with the rates reported in previous studies. Detection of a human epidermal growth factor receptor-2-positive metastasis with a human epidermal growth factor receptor-2-negative primary tumor suggests that investigation of human epidermal growth factor receptor-2 is also required for the metastatic lesion and that trastuzumab could be administered in the case of a positive result.

Comparison of WHO 2000 and WHO 2010 classifications of gastroenteropancreatic neuroendocrine tumors.

BACKGROUND/AIMS Grading and staging are important in gastroenteropancreatic neuroendocrine tumors for directing treatment. In this study, we evaluated the histopathological parameters of gastroenteropancreatic neuroendocrine tumors and statistically analyzed the correlations of these parameters between the World Health Organization (WHO) 2000 and 2010 classifications. MATERIALS AND METHODS A total of 77 cases diagnosed as neuroendocrine tumors were included in the study. Cases were classified according to the WHO 2000 and WHO 2010 classification systems, and the differences and correlations between the two systems were discussed. RESULTS Among the 50 cases that were diagnosed as well-differentiated neuroendocrine tumor according to WHO 2000, 45 were found to be Grade 1 and 5 were found to be Grade 2 according to the WHO 2010 classification. Among the 8 cases with well-differentiated neuroendocrine carcinoma according to WHO 2000; 5 and 3 were Grade 1 and Grade 2, respectively, according to the WHO 2010 classification. All of the 19 cases with poorly differentiated neuroendocrine carcinoma according to WHO 2000 were found to be Grade 3 according to the WHO 2010 classification. No differences were found between the classifications in the poorly differentiated group with a full correlation between the two classifications. CONCLUSION Although WHO 2000 seems to be a better classification to predict prognosis, since it is based on various parameters, such as depth of invasion, angiolymphatic invasion, and presence of metastasis, it was concluded that there was no difference between the WHO 2000 and WHO 2010 classification, which is based on only the number of mitoses and Ki-67 proliferation index.

Effects of chronic treatment with valproate and oxcarbazepine on testicular development in rats.

PURPOSE The aim of this study was to examine the potential effects of valproate (VPA) and oxcarbazepine (OXC) on testicular development in rats. METHODS Forty-two Wistar rats were randomly divided into three groups of 14 rats each. Each group received the following via gavage over 90 days: group 1, tap water (control group); group 2, VPA (300mg/kg/day); group 3, OXC (100mg/kg/day). After sacrifice, body, testicular and epididymidis weights were measured. Testes were sampled, fixed and processed, and quantitative morphometric analysis of Sertoli cells, spermatocytes and spermatids was performed in stages II, V and XII by histopathological examination. Immunohistochemical staining was performed to transform growth factor beta 1 (TGF-β1) and p53, and the apoptotic index was assessed using the TUNEL method. RESULTS Testis and relative testis weights were significantly lower in the VPA group compared to the control group (p<0.05). Spermatogonia, pachytene spermatocyte and round spermatocyte numbers decreased in all stages in both the VPA and OXC groups compared to the control group, though this was not statistically significant (p>0.05). Apoptotic cell counts and p53 immunoreaction were significantly high and TGF-β1 expression was significantly lower in the VPA group compared to that of the control group (p<0.05). In the OXC group, p53 immunoreaction and TGF-β1 expression decreased compared to the control group, but this difference did not attain statistical significance (p>0.05). CONCLUSIONS Our results show that VPA treatment from prepuberty to adulthood significantly negatively affects spermatogenesis, not only by reducing testicular weight, but also by increasing apoptotic death and p53 and decreasing TGF-β1 activation. OXC has a minimal side effect on testicular development.

Mucosal melanoma of the head and neck: recurrence characteristics and survival outcomes

OBJECTIVE The aim of this study was to review oncologic outcomes and recurrence characteristics of head and neck mucosal melanomas (HNMMs) managed at a tertiary referral center. STUDY DESIGN Clinical records of 10 patients who were managed for HNMMs between 2001 and 2013 were retrospectively analyzed. RESULTS The median age was 66 years (range 28-76 years) and male/female (M/F) ratio was 1:5. The 3-year disease-free survival (DFS) rates and overall survival (OS) rates were 11.7% and 35%, respectively; and the 5-year DFS rates and OS rates 11.7% and 23.3%, respectively. The median DFS and OS periods were 12 months (range 2-36 months) and 17 months (range 7-96 months), respectively. The rates of development of local, regional, and systemic recurrences were 20%, 50%, and 80%, respectively. Lungs were involved in all patients who had distant metastasis. CONCLUSIONS This study shows that HNMMs has a very aggressive course and that distant metastases are common. For this reason, systemic control of the disease is an important aim of treatment.

Prototheca zopfii Colitis in Inherited CARD9 Deficiency

Human protothecosis is a rare microalgae infection, and its dissemination typically occurs in immunocompromised individuals, but no specific immune defect has been reported. Here, we describe an 8-year-old daughter of a consanguineous union with abdominal pain and bloody diarrhea for 3 months who was found to have pancolitis with numerous microalgae identified as Prototheca zopfii. In the absence of a known immunodeficiency, exome sequencing was performed, which uncovered a novel recessive frameshift mutation in CARD9 (p.V261fs). This report highlights that CARD9 deficiency should be investigated in patients with unexplained systemic/visceral protothecosis and suggests a new mechanistic insight into anti-Prototheca immunity.