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    Effect of apoptosis and response of extracellular matrix proteins after chemotherapy application on human breast cancer cell spheroids
    (Professor D A Spandidos, 2006) Oktem, G; Vatansever, S; Ayla, S; Uysal, A; Aktas, S; Karabulut, B; Bilir, A
    Multicellular Tumor Spheroid (NITS) represents a three-dimentional structural form of tumors in laboratory conditions, and it has the characteristics of avascular micrometastases or intervascular spaces of big tumors. Recent studies indicate that extracellular matrix (ECM) proteins play a critical role in tumor metastasis, therefore normal and cancer cells require an ECM for survival, proliferation and differentiation. Doxorubicin and Docetaxel are widely used in the therapy of breast cancer, as well as in in vivo and in vitro studies. In this study, we examined the effect of apoptosis and proliferation of cells on the human breast cancer cell line, MCF-7, by using p53, bcl-2 and Ki67 gene expression, and the tendency to metastasis with extracellular matrix proteins, laminin and type IV collagen after chemotherapy in the spheroid model. The apoptotic cell death in situ was detected by TUNEL method. TUNEL-positive cells and positive immunoreactivities of laminin, type IV collagen, p53 and, bel-2 were detected in the control group. There was no laminin and type IV collagen immunoreactivities in spheroids of drug groups. While TUNEL-positive cells and p53 immunoreactivity were detected in Docetaxel, Doxorubicin and Docetaxel/Doxorubicin groups, p53 immunoreactivity was not observed in the Docetaxel group. There was no bcl-2 immunoreactivity in either drug group. In addition, we did not detect Ki67 immunoreactivity in both control and drug treatment groups. However, the absence of Ki67 protein in MCF-7 breast multicellular tumor spheroids is possibly related to the cells in GO or S phase. These agents may affect the presence of ECM proteins in this in vitro model of micrometastasis of spheroids. These findings suggest that the possible mechanism of cell death in Doxorubicin and Docetaxel/Doxorubicin treatment groups is related to apoptosis through the p53 pathway. However, we considered the possiblity that there is another control mechanism for the Docetaxel group.
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    Experience of the Izmir pediatric oncology group on neuroblastoma: IPOG-NBL-92 protocol
    (Taylor & Francis Inc, 2003) Olgun, N; Kansoy, SS; Aksoylar, S; Cetingul, N; Vergin, C; Oniz, H; Sarialioglu, F; Kantar, M; Uysal, K; Tuncyurek, M; Kargi, A; Aktas, S; Bayol, U; Karaca, I; Arikan, A; Balik, E; Aktug, TJ; Elmas, N; Kovanlikaya, A; Kinay, M; Anacak, Y; Degirmenci, B; Burak, Z
    This multicentric study aimed to bring neuroblastoma patients together under IPOG-NBL-92 protocol and evaluate the results within the period between 1992 and 2001 in Izmir. Sixty-seven neuroblastoma patients from 4 pediatric oncology centers in Izmir were included in the study. IPOG-NBL-92 protocol modified from German Pediatric Oncology (GPO)-NB-90 protocol was applied: Patients in stage 1 received only surgery, while surgery plus 4 chemotherapy courses (cisplatin, vincristine, ifosfamide) were given in stage 2 and surgery plus 6 chemotherapy courses (cisplatin, vincristine, ifosfamide, epirubicin, cyclophosphamide) were given in stages 3 and 4 patients. In patients who were kept in complete remission (CR), a maintenance therapy of one year was applied. Radiotherapy was given to the primary site following induction chemotherapy plus surgery in stages 3 and 4 patients with partial remission (PR). The stages of the patients were as follows: 5% in stage 1, 39% in stage 3, 49% in stage 4, and 7% in stage 4S. Primary tumor site was abdomen in 88% of cases. CR rates were as 100% in stage 1, 76% in stage 3, 35% in stage 4, and 75% in stage 4S. Relapse was observed in 32% of patients in a median of 19 months. The median follow-up time for survivors was 33 (17-102) months. Five-year OS rate was 31% and the EFS rate was 30% in all patients. Five-year overall and event-free survival rates were 63 and 30% in stage 3, but 6 and 5%, respectively, in stage 4 patients. Univariate analysis established that the age, stage, primary tumor site, and high LDH and NSE levels conferred a significant difference. The IPOG-NBL-92 protocol has proved to be satisfactory with tolerable toxicity and reasonable CR and survival rates. However, more effective treatments suitable to Turkey's social and economic conditions are urgently needed for children over 1 year of age with advanced neuroblastoma.
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    Experience of the Izmir pediatric oncology group on neuroblastoma: IPOG-NBL-92 protocol
    (Taylor & Francis Inc, 2003) Olgun, N; Kansoy, SS; Aksoylar, S; Cetingul, N; Vergin, C; Oniz, H; Sarialioglu, F; Kantar, M; Uysal, K; Tuncyurek, M; Kargi, A; Aktas, S; Bayol, U; Karaca, I; Arikan, A; Balik, E; Aktug, TJ; Elmas, N; Kovanlikaya, A; Kinay, M; Anacak, Y; Degirmenci, B; Burak, Z
    This multicentric study aimed to bring neuroblastoma patients together under IPOG-NBL-92 protocol and evaluate the results within the period between 1992 and 2001 in Izmir. Sixty-seven neuroblastoma patients from 4 pediatric oncology centers in Izmir were included in the study. IPOG-NBL-92 protocol modified from German Pediatric Oncology (GPO)-NB-90 protocol was applied: Patients in stage 1 received only surgery, while surgery plus 4 chemotherapy courses (cisplatin, vincristine, ifosfamide) were given in stage 2 and surgery plus 6 chemotherapy courses (cisplatin, vincristine, ifosfamide, epirubicin, cyclophosphamide) were given in stages 3 and 4 patients. In patients who were kept in complete remission (CR), a maintenance therapy of one year was applied. Radiotherapy was given to the primary site following induction chemotherapy plus surgery in stages 3 and 4 patients with partial remission (PR). The stages of the patients were as follows: 5% in stage 1, 39% in stage 3, 49% in stage 4, and 7% in stage 4S. Primary tumor site was abdomen in 88% of cases. CR rates were as 100% in stage 1, 76% in stage 3, 35% in stage 4, and 75% in stage 4S. Relapse was observed in 32% of patients in a median of 19 months. The median follow-up time for survivors was 33 (17-102) months. Five-year OS rate was 31% and the EFS rate was 30% in all patients. Five-year overall and event-free survival rates were 63 and 30% in stage 3, but 6 and 5%, respectively, in stage 4 patients. Univariate analysis established that the age, stage, primary tumor site, and high LDH and NSE levels conferred a significant difference. The IPOG-NBL-92 protocol has proved to be satisfactory with tolerable toxicity and reasonable CR and survival rates. However, more effective treatments suitable to Turkey's social and economic conditions are urgently needed for children over 1 year of age with advanced neuroblastoma.
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    Intercostal variation for age estimation - Are the standards for the right 4(th) rib applicable for other ribs?
    (Collegium Antropologicum, 2004) Aktas, EO; Kocak, A; Aktas, S; Yemiscigil, A
    Age estimation of unknown skeletal remains is very important in forensic medicine. Morphologic methods are fast and easy to use for purpose of age determination. The sternal ends of the ribs are a reliable method of age estimation from late adolescence to old age. Iscan et al developed a phase analysis method for the right 4(th) rib that was sex and race specific. The purpose of this study is to determine the accuracy of the standards of age estimation from the right 4(th) and other rib using the phase analysis for the Turkish population. The sample consisted of right and left 3(rd), 4(th) and 5(th) ribs from 34 Turkish women and 76 men. There were statistically significant variations found on the right 5(th), left 3(rd), 4(th), and 5(th), ribs according to these standards in men for phases 5, 6, and 7. For women, all the right and left ribs included in this study were in concordance with right 4(th) rib standards in all phases.
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    Role of vascularization in determining the time of hypoxic-ischemic encephalopathy in the neonate
    (Sci Printers & Publ Inc, 2003) Aktas, EO; Aktas, S; Ortac, R; Diniz, G
    OBJECTIVE: To examine the role of vascularization in determining the time of hypoxic-ischemic encephalopathy (HIEP). STUDY DESIGN: Brain sections of 126 neonatal autopsy cases were examined for edema, gliosis, congestion, inflammation and ischemia. Capillary vessels were examined with both reticulum stains and antibody against CD34. Vascular surface density (VSD) and number of vessels per stroma (NVES) were calculated by stereologic methods. RESULTS: Among 126 cases, 64 were male (50.8%) and 62 female (49.2%). In 25 cases HIEP was observed; 14 had a pregnancy history of hypertension, eclampsia or diabetes mellitus in the mother, with fetal distress or underdeveloped features. Statistically, NVES was strongly related to primary HIEP. However, the HIEP and non-HIEP cases revealed no differences in NVES and VSD means. CONCLUSION: Vascularization, especially NVES, helps in determining whether an HIEP case is pregnancy related or due to end-stage changes of dying, but is not an indicator of HIEP.
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    Role of vascularization in determining the time of hypoxic-ischemic encephalopathy in the neonate
    (Sci Printers & Publ Inc, 2003) Aktas, EO; Aktas, S; Ortac, R; Diniz, G
    OBJECTIVE: To examine the role of vascularization in determining the time of hypoxic-ischemic encephalopathy (HIEP). STUDY DESIGN: Brain sections of 126 neonatal autopsy cases were examined for edema, gliosis, congestion, inflammation and ischemia. Capillary vessels were examined with both reticulum stains and antibody against CD34. Vascular surface density (VSD) and number of vessels per stroma (NVES) were calculated by stereologic methods. RESULTS: Among 126 cases, 64 were male (50.8%) and 62 female (49.2%). In 25 cases HIEP was observed; 14 had a pregnancy history of hypertension, eclampsia or diabetes mellitus in the mother, with fetal distress or underdeveloped features. Statistically, NVES was strongly related to primary HIEP. However, the HIEP and non-HIEP cases revealed no differences in NVES and VSD means. CONCLUSION: Vascularization, especially NVES, helps in determining whether an HIEP case is pregnancy related or due to end-stage changes of dying, but is not an indicator of HIEP.
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    Treatment and prophylaxis with sucralfate ameliorates hypoxia/reoxygenation-induced intestinal injury in pup rats
    (Int Scientific Information, Inc, 2005) Sencan, AB; Sencan, A; Aktas, S; Habif, S; Kabaroglu, C; Parildar, Z; Karaca, I