Induction of Autophagy by Low Dose of Cisplatin in H460 Lung Cancer Cells / 결핵및호흡기질환

BACKGROUND: Most lung cancer patients receive systemic chemotherapy at an advanced stage disease. Cisplatin-based chemotherapy is the main regimen for treating advanced lung cancer. Recently, autophagy has become an important mechanism of cellular adaptation under starvation or cell oxidative stress. The purpose of this study was to determine whether or not autophagy can occurred in cisplatin-treated lung cancer cells. METHODS: H460 cells were incubated with RPMI 1640 and treated in 5 micrometer or 20 micrometer cisplatin concentrations at specific time intervals. Cells surviving cisplatin treatment were measured and compared using an MTT cell viability assay to cells that underwent apoptosis with autophagy by nuclear staining, apoptotic or autophagic related proteins, and autophagic vacuoles. The development of acidic vascular organelles was using acridine orange staining and fluorescent expression of GFP-LC3 protein in its transfected cells was observed to evaluate autophagy. RESULTS: Lung cancer cells treated with 5 micrometer cisplatin-treated were less sensitive to cell death than 20 micrometer cisplatin-treated cells in a time-dependent manner. Nuclear fragmentation at 5 micrometer was not detected, even though it was discovered at 20 micrometer. Poly (ADP-ribose) polymerase cleavages were not detected in 5 micrometer within 24 hours. Massive vacuolization in the cytoplasm of 5 micrometer treated cells were observed. Acridine orange stain-positive cells was increased according in time-dependence manner. The autophagosome-incorporated LC3 II protein expression was increased in 5 micrometer treated cells, but was not detected in 20 micrometer treated cells. The expression of GFP-LC3 were increased in 5 micrometer treated cells in a time-dependent manner. CONCLUSION: The induction of autophagy occurred in 5 micrometer dose of cisplatin-treated lung cancer cells.

Induction of Autophagy by Low Dose of Cisplatin in H460 Lung Cancer Cells / 결핵및호흡기질환

BACKGROUND: Most lung cancer patients receive systemic chemotherapy at an advanced stage disease. Cisplatin-based chemotherapy is the main regimen for treating advanced lung cancer. Recently, autophagy has become an important mechanism of cellular adaptation under starvation or cell oxidative stress. The purpose of this study was to determine whether or not autophagy can occurred in cisplatin-treated lung cancer cells. METHODS: H460 cells were incubated with RPMI 1640 and treated in 5 micrometer or 20 micrometer cisplatin concentrations at specific time intervals. Cells surviving cisplatin treatment were measured and compared using an MTT cell viability assay to cells that underwent apoptosis with autophagy by nuclear staining, apoptotic or autophagic related proteins, and autophagic vacuoles. The development of acidic vascular organelles was using acridine orange staining and fluorescent expression of GFP-LC3 protein in its transfected cells was observed to evaluate autophagy. RESULTS: Lung cancer cells treated with 5 micrometer cisplatin-treated were less sensitive to cell death than 20 micrometer cisplatin-treated cells in a time-dependent manner. Nuclear fragmentation at 5 micrometer was not detected, even though it was discovered at 20 micrometer. Poly (ADP-ribose) polymerase cleavages were not detected in 5 micrometer within 24 hours. Massive vacuolization in the cytoplasm of 5 micrometer treated cells were observed. Acridine orange stain-positive cells was increased according in time-dependence manner. The autophagosome-incorporated LC3 II protein expression was increased in 5 micrometer treated cells, but was not detected in 20 micrometer treated cells. The expression of GFP-LC3 were increased in 5 micrometer treated cells in a time-dependent manner. CONCLUSION: The induction of autophagy occurred in 5 micrometer dose of cisplatin-treated lung cancer cells.

Clinical Application of 3-D Conformal Radiotherapy for Carcinoma of the Ethmoid Sinus: I. Comparative Analysis Between Conventional 2-D and 3-D Conformal Plans / 대한치료방사선과학회지

PURPOSE: This is study of whether 3-D conformal radiotherapy for carcinomas of the ethmoid sinus were better than those treated with conventional 2-D plan. MATERIALS AND METHODS: The 3-D conformal treatment plans were compared with conventional 2-D plans in 4 patients with malignancy of the ethmoid sinus. Isodose distribution, dose statistics, and dose volume histogram of the planning target volume were used to evaluate differences between 2-D and 3-D plans. In addition, the risk of radiation exposure of surrounding normal critical organs are evaluated by means of point dose calculation and dose volume histogram. RESULTS : 3-D conformal treatment plans for each patient that the better tumor coverages by the planning target volume with improved dose homogeneity, compared to 2-D conventional treatment plans in the same patient. On the other hand, the radiation dose distributions to the surrounding normal tissue organs, such as the orbit and optic nerves are not significantly reduced with our technique, but a substantial sparing in the brain stem and optic chiasm for each patient. CONCLUSION : Our findings represented the potential advantage of 3-D treatment planning for dose homogeniety as well as sparing of the normal tissue surrounding the tumor. However, further investigational studies are required to define the clinical benefit.

The Role of Adjuvant Postoperative Radiotherapy in Curative Resectable Sigmoid Colon Carcinoma / 대한치료방사선과학회지

PURPOSE: To evaluate the role of postoperative radiation therapy after curative resection of sigmoid colon cancer MATERIALS AND METHODS: From 1988 to 1993, a total of 93 patients with curative resectable sigmoid colon cancer of modified Astler-Coller (MAC) stage B2, B3, C2, C3 was divided into two groups on the basis of those who received radiation treatment and those who did not. Forty-three patients who treated by surgery alone were classified as postop RT ( group. The remaining 50 patients who underwent postoperative radiotherapy were classified as postop RT (+) group. In all patients in postop RT (+) group, radiation therapy was delivered using 4 or 10 MV linear accelerators to treat the tumor bed with approximately 5cm margin to a total dose 50.4-61Gy (median 54Gy) in 1.8Gy per fraction. Thirty-two patients were treated with 5- Fluorouracil based adjuvant chemotherapy at least 3 cycles, but these was no significant difference between two groups. Treatment failure pattern, 5-year local failure-free survival rates (LFFS), and 5-year disease-free survival rates (DFS) were compared between two groups. RESULTS: Five year LFFS and DFS were 85.1%, 68.5%, respectively. In postop RT (-) group, LFFS was 76.2%, compared with 91.7% in postop RT (+) group. Improved LFFS and DFS were seen for patients with stage C3 sigmoid colon carcinoma with postoperative radiation therapy compared with postop RT (-) group (P=0.01, P=0.06 respectively). In stage B3, LFFS washigher in postop RT (+) group than that in postop RT (-) group, although it was not significant. Especially, local control was higher in stage T4 in postop RT (+) group than that in postop RT (-) group. CONCLUSION: This study showed significantly improved LFFS and DFS in MAC Stage C3 and improved tendency of LFFS and DFS in MAC Stage B3 disease. Large scale prospective study is required to verify the role of adjuvant radiation therapy in resectable sigmoid colon cancer.