Oxidative stress and imbalance in the oxidant/antioxidant system have a critical role in carcinog... more Oxidative stress and imbalance in the oxidant/antioxidant system have a critical role in carcinogenesis by affecting necrosis and apoptosis. The aim of this study is to evaluate the oxidant/antioxidant status and cell death modes in patients with oral squamous cell carcinoma (OSCC). Twenty-nine patients with OSCC and 29 control subjects were included in the study. The levels of malondialdehyde (MDA), advanced oxidation protein products (AOPP) and ferric reducing antioxidant power (FRAP) were determined in plasma samples of all subjects. The necrotic and apoptotic cell death modes were evaluated with M65 ELISA and M30 ELISA, respectively. MDA and AOPP values as oxidative stress markers were higher in patients with OSCC than in the control group. FRAP values evaluating plasma antioxidant status increased in OSCC patients. M65 and M30 levels indicating necrosis and apoptosis were significantly higher in OSCC patients compared to controls. There were significant correlations between MDA, AOPP and FRAP; M65 and M30 values. The elevated levels of oxidative stress markers together with the increase of antioxidant capacity and the presence of a strong correlation between MDA, AOPP and FRAP suggest an activation of antioxidant defense against accentuated oxidative stress determined in OSCC. Enhanced oxidation of lipids and proteins may cause decomposition of cell membranes with subsequent leakage of cytoskeletal cytokeratins as CK18 and caspase-cleaved CK18 (evaluated as M65 and M30, respectively) in the circulation, suggesting that both cell death modes are affected in OSCC.
10063 Background: Intracranial germ cell tumors (iGCT) constitute 1% of all malignant neoplasms i... more 10063 Background: Intracranial germ cell tumors (iGCT) constitute 1% of all malignant neoplasms in children. The aim of this study is to evaluate the demographic characteristics, therapy, and long term outcome of children with iGCT in a single institution. Methods: 16 children (9 female, 7 male) with a median age of 11 years (10 months-18 yrs) treated for iGCT between 1990 and 2008 were evaluated retrospectively. They were treated according to our institutional protocol. Patients > 13 years old with germinomas recieved radiotherapy alone (2520 cGy craniospinal/1980 cGy local boost), patients <13 yrs old recieved 2 courses of etoposide, cisplatinum followed with cranial radiotherapy. Nongerminoma patients recieved 3 courses of bleomycine, etoposide, cisplatinum followed by 3600 cGy craniospinal / 1980 cGy local boost RT. Results: Presenting clinical features were diabetes insipidus (7), raised intracranial pressure (12), visual changes-oculomotor palsies (6), hypopituitarism (4...
IntroductionThe survival of children with Hodgkin lymphoma have increased significantly raising t... more IntroductionThe survival of children with Hodgkin lymphoma have increased significantly raising the issue of decreasing late effects by using risk adapted treatment. Hodgkin lymphoma has different epidemiologic features in developed and developing countries. In this study the epidemiologic, clinical characteristics and outcome of children with Hodgkin disease treated with a risk adapted treatment over a 25 year period are evaluated. MethodsThis retrospective study evaluates the clinical characteristics and outcome of 122 children treated with the same institutional risk-adapted protocol in the Istanbul University, Oncology Institute between 1991-2016. Clinical staging was done according to Ann-Arbor staging, all patients had biopsy confirmation and the WHO histopathological classification was used. Imaging (ultrasound, CT/MRI and/or PET-CT since 2004) was done in all patients. Bone marrow aspiration and biopsy was done for all with B symptoms or risk group 2 and 3. Risk group 1 (cli...
Objective: Although cancer chemotherapy has been used for more than seventy years, its definitive... more Objective: Although cancer chemotherapy has been used for more than seventy years, its definitive mechanism of action is not known. Many studies indicate that beyond DNA the collagen connective tissue matrix is also affected. This database analysis aims to determine the extent of DNA versus collagen perception in scientific papers indexed under PubMed. Materials and methods: The PubMed database scanned on September, 15, 2021 using following keywords and combinations; "cancer", "cancer chemotherapy", "cancer chemotherapy AND damage”, “chemotherapy AND mechanism AND damage”, "chemotherapy AND clinical" as nominator. The number of items found for each search was proportioned in terms “DNA versus collagen” and the ratio was accepted as the perception shift coefficient. Results: Tested with the p1-p2 analysis to calculate the difference between the two proportions in both search items. Based on the main rule under the assumption that “all cells have DNA...
Background/Aim: Previous studies on fractionation in radiation therapy have been mainly based on ... more Background/Aim: Previous studies on fractionation in radiation therapy have been mainly based on applying equal doses over at least 6 h. The main purpose of fractionation is to increase normal tissue tolerance rather than tumor sensitivity. Thus, one can apply higher doses to the tumor. In contrast, new molecular studies indicate that high and low doses of radiation act by different mechanisms. This study was conducted to investigate the radiobiological effect of asymmetrical radiation doses. Methods: This is an experimental study done in vitro with a G6 glioma cell line to investigate the responses when C6 glioma cells are irradiated with single doses of 30 and 230 cGy using an orthovoltage therapy device or doses split into 30 and 200 and 115 and 115 cGy within periods of 15 and 30 min. A total of 5 × 103 cells were transferred to polyethylene culture flasks for colony formation. A cluster containing more than 30 cells was considered a new colony. Results: A single dose of 230 cGy...
Beslenmenin nasil olmasi gerektigi; saglik, hastalik, mevsim gibi durumlardaki olasi degisiklikle... more Beslenmenin nasil olmasi gerektigi; saglik, hastalik, mevsim gibi durumlardaki olasi degisiklikler yeterince iyi bilinmemektedir. Gidanin endustrilesmesiyle birlikte ortaya cikan degisiklikler, gida uretimi ve islenmesinin de sorgulanmasina neden olmustur. Benzer bilgi eksikligi dokularin yapimi ve duzenlenmesi acisindan da gecerlidir. Tiptaki genel kabullenmenin aksine, sagligin korunmasi ancak gercek gidalarin tuketilmesiyle mumkundur. Bu degerlendirmede gidanin endustrilesme surecinin saglik acisindan yarattigi sakincalari irdelenmektedir. Turkiye geneline dagilmis ve orgutlu isgucune sahip seker fabrikalari; gercek gida uretiminin butun alanlarda ayrilmaz bir parcasi olmalidir
Ewing’s sarcoma/primitive neuroectodermal tumor (ES/PNET) of the penis has been very rarely defin... more Ewing’s sarcoma/primitive neuroectodermal tumor (ES/PNET) of the penis has been very rarely defined. We report a case of a 19-year-old patient with a tumor, localized in the dorsal side of penis, composed of small round cells with diffuse membranous mic-2 (CD99) immunopositivity. The patient was treated with multiagent chemotherapy and radiotherapy.
10040 Background: Osteosarcoma is the most frequent bone tumor in children and adolescents. The a... more 10040 Background: Osteosarcoma is the most frequent bone tumor in children and adolescents. The aim of this study is to evaluate the demographic characteristics, therapy, and long term outcome of children with osteosarcoma in a single institution. Methods: Between January 1990 and December 2006, 94 children (53 male, 41 female) with a median age of 13 (5–16) years and a histopathologic diagnosis of osteosarcoma were treated with an institutional chemotherapy regimen comprising of 6 courses (3 pre-, 3 postoperatively) of epirubicin (90 mg/m2), cisplatin(100 mg/m2), and ifosfamide(2 g/m2 × 3 days) every 3 weeks. Results: The median follow-up time was 36 (2–219) months. 68 patients were alive at the time of analysis. 26 patients died; 20 of disease, 5 of toxicity, and 1 of second malignancy (acute myeloid leukemia). 90% of the patients had a limb salvage. 5 and 10 year OS for all patients were 64.7 % ( [95 % CI] 74.8–52.94 %) and 62.2 % (95 % CI 74.6–49.9 %), respectively. 5 and 10 yea...
Oxidative stress and imbalance in the oxidant/antioxidant system have a critical role in carcinog... more Oxidative stress and imbalance in the oxidant/antioxidant system have a critical role in carcinogenesis by affecting necrosis and apoptosis. The aim of this study is to evaluate the oxidant/antioxidant status and cell death modes in patients with oral squamous cell carcinoma (OSCC). Twenty-nine patients with OSCC and 29 control subjects were included in the study. The levels of malondialdehyde (MDA), advanced oxidation protein products (AOPP) and ferric reducing antioxidant power (FRAP) were determined in plasma samples of all subjects. The necrotic and apoptotic cell death modes were evaluated with M65 ELISA and M30 ELISA, respectively. MDA and AOPP values as oxidative stress markers were higher in patients with OSCC than in the control group. FRAP values evaluating plasma antioxidant status increased in OSCC patients. M65 and M30 levels indicating necrosis and apoptosis were significantly higher in OSCC patients compared to controls. There were significant correlations between MDA, AOPP and FRAP; M65 and M30 values. The elevated levels of oxidative stress markers together with the increase of antioxidant capacity and the presence of a strong correlation between MDA, AOPP and FRAP suggest an activation of antioxidant defense against accentuated oxidative stress determined in OSCC. Enhanced oxidation of lipids and proteins may cause decomposition of cell membranes with subsequent leakage of cytoskeletal cytokeratins as CK18 and caspase-cleaved CK18 (evaluated as M65 and M30, respectively) in the circulation, suggesting that both cell death modes are affected in OSCC.
10063 Background: Intracranial germ cell tumors (iGCT) constitute 1% of all malignant neoplasms i... more 10063 Background: Intracranial germ cell tumors (iGCT) constitute 1% of all malignant neoplasms in children. The aim of this study is to evaluate the demographic characteristics, therapy, and long term outcome of children with iGCT in a single institution. Methods: 16 children (9 female, 7 male) with a median age of 11 years (10 months-18 yrs) treated for iGCT between 1990 and 2008 were evaluated retrospectively. They were treated according to our institutional protocol. Patients > 13 years old with germinomas recieved radiotherapy alone (2520 cGy craniospinal/1980 cGy local boost), patients <13 yrs old recieved 2 courses of etoposide, cisplatinum followed with cranial radiotherapy. Nongerminoma patients recieved 3 courses of bleomycine, etoposide, cisplatinum followed by 3600 cGy craniospinal / 1980 cGy local boost RT. Results: Presenting clinical features were diabetes insipidus (7), raised intracranial pressure (12), visual changes-oculomotor palsies (6), hypopituitarism (4...
IntroductionThe survival of children with Hodgkin lymphoma have increased significantly raising t... more IntroductionThe survival of children with Hodgkin lymphoma have increased significantly raising the issue of decreasing late effects by using risk adapted treatment. Hodgkin lymphoma has different epidemiologic features in developed and developing countries. In this study the epidemiologic, clinical characteristics and outcome of children with Hodgkin disease treated with a risk adapted treatment over a 25 year period are evaluated. MethodsThis retrospective study evaluates the clinical characteristics and outcome of 122 children treated with the same institutional risk-adapted protocol in the Istanbul University, Oncology Institute between 1991-2016. Clinical staging was done according to Ann-Arbor staging, all patients had biopsy confirmation and the WHO histopathological classification was used. Imaging (ultrasound, CT/MRI and/or PET-CT since 2004) was done in all patients. Bone marrow aspiration and biopsy was done for all with B symptoms or risk group 2 and 3. Risk group 1 (cli...
Objective: Although cancer chemotherapy has been used for more than seventy years, its definitive... more Objective: Although cancer chemotherapy has been used for more than seventy years, its definitive mechanism of action is not known. Many studies indicate that beyond DNA the collagen connective tissue matrix is also affected. This database analysis aims to determine the extent of DNA versus collagen perception in scientific papers indexed under PubMed. Materials and methods: The PubMed database scanned on September, 15, 2021 using following keywords and combinations; "cancer", "cancer chemotherapy", "cancer chemotherapy AND damage”, “chemotherapy AND mechanism AND damage”, "chemotherapy AND clinical" as nominator. The number of items found for each search was proportioned in terms “DNA versus collagen” and the ratio was accepted as the perception shift coefficient. Results: Tested with the p1-p2 analysis to calculate the difference between the two proportions in both search items. Based on the main rule under the assumption that “all cells have DNA...
Background/Aim: Previous studies on fractionation in radiation therapy have been mainly based on ... more Background/Aim: Previous studies on fractionation in radiation therapy have been mainly based on applying equal doses over at least 6 h. The main purpose of fractionation is to increase normal tissue tolerance rather than tumor sensitivity. Thus, one can apply higher doses to the tumor. In contrast, new molecular studies indicate that high and low doses of radiation act by different mechanisms. This study was conducted to investigate the radiobiological effect of asymmetrical radiation doses. Methods: This is an experimental study done in vitro with a G6 glioma cell line to investigate the responses when C6 glioma cells are irradiated with single doses of 30 and 230 cGy using an orthovoltage therapy device or doses split into 30 and 200 and 115 and 115 cGy within periods of 15 and 30 min. A total of 5 × 103 cells were transferred to polyethylene culture flasks for colony formation. A cluster containing more than 30 cells was considered a new colony. Results: A single dose of 230 cGy...
Beslenmenin nasil olmasi gerektigi; saglik, hastalik, mevsim gibi durumlardaki olasi degisiklikle... more Beslenmenin nasil olmasi gerektigi; saglik, hastalik, mevsim gibi durumlardaki olasi degisiklikler yeterince iyi bilinmemektedir. Gidanin endustrilesmesiyle birlikte ortaya cikan degisiklikler, gida uretimi ve islenmesinin de sorgulanmasina neden olmustur. Benzer bilgi eksikligi dokularin yapimi ve duzenlenmesi acisindan da gecerlidir. Tiptaki genel kabullenmenin aksine, sagligin korunmasi ancak gercek gidalarin tuketilmesiyle mumkundur. Bu degerlendirmede gidanin endustrilesme surecinin saglik acisindan yarattigi sakincalari irdelenmektedir. Turkiye geneline dagilmis ve orgutlu isgucune sahip seker fabrikalari; gercek gida uretiminin butun alanlarda ayrilmaz bir parcasi olmalidir
Ewing’s sarcoma/primitive neuroectodermal tumor (ES/PNET) of the penis has been very rarely defin... more Ewing’s sarcoma/primitive neuroectodermal tumor (ES/PNET) of the penis has been very rarely defined. We report a case of a 19-year-old patient with a tumor, localized in the dorsal side of penis, composed of small round cells with diffuse membranous mic-2 (CD99) immunopositivity. The patient was treated with multiagent chemotherapy and radiotherapy.
10040 Background: Osteosarcoma is the most frequent bone tumor in children and adolescents. The a... more 10040 Background: Osteosarcoma is the most frequent bone tumor in children and adolescents. The aim of this study is to evaluate the demographic characteristics, therapy, and long term outcome of children with osteosarcoma in a single institution. Methods: Between January 1990 and December 2006, 94 children (53 male, 41 female) with a median age of 13 (5–16) years and a histopathologic diagnosis of osteosarcoma were treated with an institutional chemotherapy regimen comprising of 6 courses (3 pre-, 3 postoperatively) of epirubicin (90 mg/m2), cisplatin(100 mg/m2), and ifosfamide(2 g/m2 × 3 days) every 3 weeks. Results: The median follow-up time was 36 (2–219) months. 68 patients were alive at the time of analysis. 26 patients died; 20 of disease, 5 of toxicity, and 1 of second malignancy (acute myeloid leukemia). 90% of the patients had a limb salvage. 5 and 10 year OS for all patients were 64.7 % ( [95 % CI] 74.8–52.94 %) and 62.2 % (95 % CI 74.6–49.9 %), respectively. 5 and 10 yea...
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