Bülent Karagöz

HLA-G expression in B chronic lymphocytic leukemia: a new prognostic marker?

Abstract Chronic lymphocytic leukemia (CLL) is characterized by a malignant clonal population of lymphocytes, which are usually of the B cell lineage. Classical Rai and Binet staging of CLL is being superseded by new prognostic markers. The mutational status of the immunoglobulin variable region heavy-chain genes segregates the disease into more benign and more malignant versions, and has been confirmed as an important prognostic marker in prospective clinical trials. A search for surrogate markers for this assay has led to flow cytometric assays for CD38 and ZAP-70 expression. The human leukocyte antigen G (HLA-G) molecule exhibits limited tissue distribution and a low polymorphism that generate seven HLA-G isoforms. HLA-G exerts multiple immunoregulatory functions. Recent studies indicate an ectopic up-regulation in tumor cells that may favor their escape from anti-tumor immune responses. For this report we studied HLA-G in parallel with CD38 and ZAP-70 in B-cell chronic lymphocytic leukemia (B-CLL) patients. HLA-G expression was studied retrospectively in circulating B-CLL cells from 20 patients by flow cytometry using the anti-HLA-G specific monoclonal antibody MEM/G9. The proportion of leukemic cells expressing HLA-G varied from 1 to 34%. We detected a statistically significant correlation between HLA-G positive (>12%) expression and progression free survival (p=0·045), but no correlation with CD38 and ZAP-70. We also detected a statistically significant difference between Binet stage A; B and C (p=0·046) and a positive correlation between IL-10 and HLA-G (p=0·044). We conclude that positive HLA-G has an effect on progression - free survival, when compared with CD38 and ZAP-70.

Effects of Different Doses of Hyperbaric Oxygen on Cisplatin-Induced Nephrotoxicity

Cisplatin, an effective antineoplastic agent, frequently induces acute renal failure in animals and humans. Hyperbaric oxygen (HBO) has been shown to prevent cisplatin-induced nephrotoxicity in rats. This study investigated the effect of two different HBO regimes on renal functions, oxidative stress, and histopathological changes in rat kidneys after cisplatin treatment. Wistar rats were divided into five groups: control, HBO, cisplatin, cisplatin plus once daily HBO, and cisplatin plus twice daily HBO. Cisplatin was given as a single intraperitoneal dose of 6 mg/kg, and HBO was applied for 60 min at 2.5 atm for six days. HBO alone did not alter any biochemical parameters or histopathological findings compared with the control group. Cisplatin increased serum urea and creatinine levels and caused severe histopathological injury. In addition, cisplatin increased lipid peroxidation and impaired superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in kidney tissue. Once daily HBO after cisplatin treatment slightly reduced serum urea and creatinine levels and attenuated histopathological injury. HBO also reduced lipid peroxidation and increased SOD and GSH-Px activities significantly. Although twice daily HBO was determined to be more effective than once daily HBO on oxidative stress parameters, it increased serum creatinine levels and histopathological injury compared with the cisplatin group. It was concluded that HBO alone does not induce nephrotoxicity and oxidative stress in rat kidneys; once daily HBO may prevent cisplatin-induced nephrotoxicity, an effect that is partially mediated by the modification of oxidant/antioxidant systems in the kidneys; and twice daily HBO potentiates cisplatin nephrotoxicity by a ROS-independent mechanism.

MicroRNA-21 as an Indicator of Aggressive Phenotype in Breast Cancer

Objective: The recently discovered microRNAs (miRNAs) are non-protein-coding, endogenous small RNAs. The aim of this study was to investigate the relationship between microRNA-21 (miR-21) and the clinicopathological features of breast cancer. Materials and Methods: Formalin-fixed, paraffin-embedded (FFPE) tissue samples were collected from 15 patients who had undergone surgery for primary breast cancer. The miR-21 expression levels in normal and cancer tissues were analyzed using real-time quantitative reverse transcriptase polymerase chain reaction (real-time qRT-PCR). The correlations between the miR-21 expression level and the stage of disease, the tumor size, lymph node involvement, hormone receptor status, human epidermal growth factor receptor 2 (HER2) status, and disease-free survival (DFS) were investigated. Results: The miR-21 expression levels were significantly higher in patients with stage III disease, patients with more than 3 axillary lymph node metastases and HER2-positive patients than in patients with stage I-II disease, patients with 1-3 axillary lymph node metastases and HER2-negative patients (p = 0.005, p = 0.037, and p = 0.014, respectively). Patients with high miR-21 expression level had a significantly shorter DFS than patients with low miR-21 expression level (median DFS: 18 and 56 months, respectively; p = 0.004). Conclusion: These results show that miR-21 is an indicator of an aggressive breast cancer phenotype and that it may be a new therapeutic target in the treatment of breast cancer in the future.

Mean platelet volume as a prognostic marker in metastatic colorectal cancer patients treated with bevacizumab-combined chemotherapy.

BACKGROUND Recent studies have revealed a prognostic impact of the MPV (mean platelet volume)/platelet count ratio in terms of survival in advanced non-small cell lung cancer. However, there has been no direct analysis of the survival impact of MPV in patients with mCRC. The aim of the study is to evaluate the pretreatment MPV of patients with metastatic and non-metastatic colorectal cancer (non-mCRC) and also the prognostic significance of pretreatment MPV to progression in mCRC patients treated with bevacizumab-combined chemotherapy. MATERIALS AND METHODS Fifty-three metastatic and ninety-five non-metastatic colorectal cancer patients were included into the study. Data on sex, age, lymph node status, MPV, platelet and platecrit (PCT) levels were obtained retrospectively from the patient medical records. RESULTS The MPV was significantly higher in the patients with mCRC compared to those with non-mCRC (7.895±1.060 versus 7.322±1.136, p=0.013). The benefit of bevacizumab on PFS was significantly greater among the patients with low MPV than those with high MPV. The hazard ratio (HR) of disease progression was 0.41 (95%CI, 0.174-0.986; p=0.04). In conclusion, despite the retrospective design and small sample size, MPV can be considered a prognostic factor for mCRC patients treated with bevacizumab-combined chemotherapy.

Immunoregulatory Function of HLA-G in Gastric Cancer

BACKGROUND Human leukocyte antigen (HLA)-G-positive gastric cancers are associated with poor survival, but links with tumor escape mechanisms remain to be determined. MATERIALS AND METHODS We used immunohistochemistry to investigate HLA-G expression, tumor infiltrating CD8+ T lymphocytes, and Treg cells in 52 gastric cancer patients. RESULTS There were 29 cancer-related deaths during the follow-up period. Kaplan-Meier analysis indicated that patients with HLA-G-positive (n=16) primary tumors had a significantly poorer prognosis than patients with HLA-G-negative tumors (n=36, p=0.008). The median survival time was 14 months and 47 months, respectively. Patients with high numbers of Tregs and low numbers of CD8+T lymphocytes in the primary tumor had a poorer prognosis than those with low numbers of Tregs and high numbers of CD8+T lymphocytes (p=0.034, p=0.043). Multivariate Cox proportional hazard regression analysis showed that HLA-G expression (hazard ratio: 2.662; 95% confidence interval: 1.242-5.723; p=0.012) and stage (hazard ratio: 2.012;95% confidence interval: 1.112-3.715; p=0.041) were independent unfavorable factors for patient survival. CONCLUSIONS We found a significant positive correlation between HLA-G expression and the number of tumor infiltrating Tregs (p=0.01) and a negative correlation with the number of CD8+T lymphocytes (p=0.041). HLA-G may protect gastric cancer cells from cytolysis by inducing Foxp3+Treg lymphocytes and suppressing CD8+T lymphocytes.

Nesfatin-1 in advanced lung cancer patients with weight loss.

The cachexia occurs frequently in lung cancer patients. Among appetite regulatory peptides, alteration of expressions of leptin and ghrelin is demonstrated in cachectic cancer patients, but nesfatin-1 has not been yet studied in cancer. We investigated serum nesfatin-1 level in advanced lung cancer patients. Forty-one lung cancer patients and 24 healthy subjects were included to the study. Nesfatin-1 serum levels were analyzed by ELISA kit. Serum nesfatin-1 levels were lower in lung cancer patients than in healthy subjects (0.52±0.19ng/ml vs 0.75±0.23ng/ml; p<0.001). In lung cancer patients with weight loss, nesfatin-1 levels were decreased compared to the patients without weight loss (0.44±0.16ng/ml vs 0.63±0.18ng/ml; p<0.001). Whereas, there were no any difference between patients without weight loss and control subjects (0.63±0.18ng/ml vs 0.75±0.23ng/ml; p:0.129) or between SCLC and NSCLC patients (0.53±0.18ng/ml vs 0.52±0.20ng/ml; p:0.458). No significant correlation was found between serum nesfatin-1 values and BMI. In conclusion, loss of fat mass may decrease serum nesfatin-1 level in lung cancer patients with weight loss. The future studies which explore biological significance of low serum nesfatin-1 level in cancer are needed.

Hemicentral Retinal Artery Occlusion in a Breast Cancer Patient Using Anastrozole

Background: Anastrozole, an aromatase inhibitor, is commonly used in the adjuvant treatment of breast cancer. Anastrozole treatment is associated with a risk of thromboembolic events and retinal vascular side effects. Herein, we present a case of hemicentral retinal artery occlusion diagnosed in a breast cancer patient using anastrozole. Case Report: A 53-year-old woman with a hypertensive and diabetic background was admitted to our hospital with breast cancer. Anastrozole treatment was started after surgery, adjuvant chemotherapy, and radiotherapy. Sudden painless loss of vision in the patient’s right eye occurred within 13 months of Anastrozole treatment. A fluorescein angiogram revealed hemicentral retinal artery occlusion. Conclusion: To the best knowledge of the authors, this is the first report of hemicentral retinal artery occlusion in an anastrozole user.

Hyperbaric Oxygen Therapy Does Not Potentiate Doxorubicin‐Induced Cardiotoxicity in Rats

The current use of doxorubicin is regarded as an absolute contraindication for hyperbaric oxygen (HBO2) therapy because of the increased risk of cardiotoxicity. The aim of this study was to investigate whether additional exposure to HBO2 during the course of doxorubicin treatment would further increase the cardiotoxicity of doxorubicin in rats. Female Wistar rats were treated with either HBO2 (n = 10) or doxorubicin (n = 8) or a combination of both treatments (n = 10) for 4 consecutive weeks and followed up for an additional 4 weeks. Cardiomyopathy was evaluated using two-dimensional and M-mode echocardiography at baseline, at the fourth, sixth and eighth weeks, and by histopathological investigation of the rat hearts at the eighth week. Doxorubicin treatment significantly reduced ejection fraction and fractional shortening (P < 0.001) and caused severe histopathological injury (P < 0.05) indicating development of cardiotoxicity. Although the combination of doxorubicin and HBO(2) also markedly reduced ejection fraction and fractional shortening (P < 0.001), this reduction was significantly less than that of doxorubicin treatment (P < 0.05). HBO2 therapy also attenuated doxorubicin-induced histopathological changes in rat hearts (P < 0.05). HBO2 alone did not alter echocardiographic parameters or histopathological findings (P > 0.05). In conclusion, HBO2 therapy does not potentiate doxorubicin-induced cardiotoxicity in rats. Cardioprotection conferred by HBO2 against doxorubicin warrants further investigation.

Hyperammonemic encephalopathy in a patient with primary hepatic neuroendocrine carcinoma

A 53-year-old male patient was admitted to our hospital with abdominal pain in the right upper quadrant. There was no change in laboratory investigations other than a slight increase in serum levels of alkaline phosphatase (ALP), alanine aminotransferase (ALT), and gamma glutamyl transferase (GGT). Computed tomography (CT) of the abdomen showed multiple hepatic nodular lesions in the liver. Tru-cut biopsy of the lesions was reported as well-differentiated neuroendocrine carcinoma. The patient received sandostatin treatment. After a few days, the patient was hospitalized in the intensive care unit with disturbance of consciousness and clinical features suggestive of encephalopathy. Serum ammonia level was found highly elevated. After the treatment with l-ornithine-l-aspartate, a remarkable improvement in the level of patient’s sensorium occurred as well as a reduction in serum ammonia level within a few days. Transarterial chemoembolization (TACE) was performed one week later. The patient’s condition began to worsen along with increase in serum ammonia level and he died because of hyperammonemic encephalopathy. There are case reports of hyperammonemia with some malignancies such as multiple myeloma, plasma cell leukemia, and leiomyosarcoma, or in some patients who have received chemotherapy. This case may suggest an association between hyperammonemia and neuroendocrine tumors.

Peripheral blood gamma-delta T cells in advanced-stage cancer patients

Gamma-delta T (γδ T) cells form a subgroup which has been reported to play a role in both natural and acquired immunity. Their levels have been found to increase in some tumour tissues. The aim of this study was to investigate the ratio of γδ T cells to all T cells in the peripheral blood of advanced-stage cancer patients; the level of γδ T cells expressing the Vδ2-T-cell receptor (TCR) chain; NKG2D receptor expression; and apoptotic (Annexin-V) γδ T-cell levels. Twenty patients with advanced-stage cancer and 13 healthy controls were included. No statistical differences were found between control and patient groups in terms of the γδ T/total T-cell ratio (P=0.53), the Vγ2-TCR expressing γδ T-cell ratio (P=0.19) or the Annexin-V ratio (P=0.48). However, NKG2D expression in γδ T cells was significantly different between the control and patient groups (P=0.014). In summary it was shown that the levels of NKG2D receptors, which are responsible for the cytolytic effect of γδ T cells, were lower in cancer patients than in healthy adults. However, no significant differences were observed in the other parameters studied between groups.