Biomedical subjects

S R Moon

Publications and source records attributed to S R Moon.

6 recordsLinked to original sources

PubMed2001

Combined chemotherapy and radiation versus radiation alone in the management of localized angiocentric lymphoma of the head and neck.

BACKGROUND AND PURPOSE: To clarify the clinical benefit derived from the combined modality therapy (CMT) comprised of chemotherapy and involved-field radiotherapy (XRT) for stage I and II angiocentric lymphomas of the head and neck. MATERIAL AND METHODS: Of 143 patients with angiocentric lymphoma of the head and neck treated at the Yonsei Cancer Center between 1976 and 1995, 104 patients (XRT group) received involved-field XRT alone with a median dose of 50.4 Gy (range: 20-70 Gy), while 39 patients (CMT group) received a median three cycles (range: 1-6 cycles) of chemotherapy before starting involved-field XRT. The response rate, patterns of failure, complications, and survival data of the XRT group were compared with those of the CMT group. RESULTS: Despite a higher response rate, local failure was the most common pattern of failure in patients of the both groups. The patterns of failure, including the systemic relapse rate were not influenced by the addition of combination chemotherapy. Although both modalities were well tolerated by the majority of patients, aberrant immunologic disorders or medical illnesses, such as a hemophagocytic syndrome, sepsis, intractable hemorrhage, or the evolution of second primary malignancies were more frequently observed in patients of the CMT group. The prognosis of patients in the XRT group was relatively poor, with a 5-year overall actuarial survival rate of 38% and disease-free survival rate of 32%, respectively. However, their clinical outcome was not altered by the addition of systemic chemotherapy. Achieving complete remission was the most important prognostic factor on univariate and multivariate analyses, but treatment modality was not found to be a prognostic variable influencing survival. CONCLUSIONS: Involved-field XRT alone for angiocentric lymphoma of the head and neck was insufficient to achieve an improved survival rate, but the combination of chemotherapy and involved-field XRT failed to demonstrate any therapeutic advantage over involved-field XRT alone.

Adolescent↗

PubMed2001

A feasibility study using three-dimensional conformal boost technique in locally advanced carcinoma of the nasopharynx.

To investigate the feasibility and efficacy of dose escalation using three-dimensional (3-D) conformal boost technique, 21 patients with stage III or IV nasopharyngeal cancer were enrolled in a prospective protocol. All patients with node metastases initially received external radiotherapy by conventional technique up to 70.2 Gy, followed by 3-D conformal radiotherapy (3-D CRT) to the boost part up to 79.2 Gy with 9 Gy increments (daily fraction of 1.8 Gy for 5 days). A modified technique with the same dose escalation of 9 Gy using 3-D CRT was applied to 7 patients without node metastases, who were treated by conventional technique up to 54 Gy, followed by 3-D CRT to boost up to a basic dose of 70.2 Gy, and then finally with dose escalation of 9 Gy. The protocol was relatively well tolerated by the majority of patients. Acute complications during the dose escalation schedule was low, with rare occurrences of grade 3 or 4 toxicity. Although late radiation-induced complications also appeared limited, 1 patient developed a temporal lobe necrosis and 2 patients suffered from sensory-neural hearing loss. There were no radiation-induced fatal complications. At a median follow-up of 48 months, only 3 patients experienced local failure and 2 patients developed distant metastases. The 5-year overall actuarial survival rate and recurrence-free survival rate for all patients were 68% and 85%, respectively. On the basis of acceptable morbidity and encouraging treatment results, we conclude that the dose escalation in 9 Gy increments using a 3-D conformal boost technique is relatively safe and efficacious, enough to be used routinely for locally advanced nasopharyngeal cancers.

Adult↗

PubMed2001

Gamma-interferon (IFN-gamma) augments apoptotic response to mistletoe lectin-II via upregulation of Fas/Fas L expression and caspase activation in human myeloid U937 cells.

Mistletoe lectin-II, a major composition of Korean mistletoe (Viscum album coloratum), is known as a potent apoptosis inducer. The previous research has demonstrated that Korean mistletoe lectin-II induces apoptosis via c-Jun N terminal kinase (JNK) activation in human myeloid U937 cells. The purpose of this research is to prove the synergistic action of mistletoe lectin-II and interferon-gamma (IFN-gamma) in the apoptotic cytotoxicity of U937. When U937 cells were treated with mistletoe lectin-II after being differentiated by IFN-gamma, the proteolytic activity of caspase-3 and 9 was markedly elevated and that of caspase-8 was prolonged for 18 hr. The activation of caspase-3-like protease requires the earlier cleavage of poly(ADP-ribose) polymerase(PARP). Caspase-1 was, however, not activated during the resting phase and nor in IFN-gamma-differentiated U937 cells. Western blot analysis revealed that, in IFN-gamma-differentiated U937 cells, the expression of Fas (CD95/APO-1) & Fas ligand(FasL) increases the apoptotic sensitivity against Mistletoe lectin-II. Fas (CD95/APO-1) & FasL were not significantly induced solely by mistletoe lectin-II. Furthermore the activity of JNK1 in U937 cells was also markedly increased with IFN-gamma-differentiation, compared to that of the control. These results suggest that the IFN-gamma-differentiation of U937 cells increases the susceptibility to mistletoe lectin-II-induced apoptosis.

Apoptosis↗

PubMed2000

Activation of c-Jun N-terminal kinase 1 (JNK1) in mistletoe lectin II-induced apoptosis of human myeloleukemic U937 cells.

Extracts of mistletoe (Viscum album var. coloratum) have been used for several decades as an anticancer immunomodulating agent in clinical fields. However, the mechanism by which the plant extracts kill tumor cells has remained elusive. We investigated the direct effects of beta-galactoside- and N-acetyl-d-galactosamine-specific mistletoe lectin II in inducing apoptotic death of U937 cells. Three distinct components of mistletoe, including beta-galactoside- and N-acetyl-D-galactosamine-specific lectin II (60 kDa), polysaccharides, and viscotoxin (5 kDa), induced apoptotic cell death, characterized by DNA ladder pattern fragmentation of U937 cells at 12 hr after treatment. Consistent with apoptosis of the cells, mistletoe extracts markedly increased the phosphotransferase activity of c-Jun N-terminal kinase 1 (JNK1)/stress-activated protein kinase (SAPK) in U937 cells. Among the three components, lectin II was the most potent in inducing apoptosis as well as JNK1 activation of U937 cells in a dose- and time-dependent manner. Catalytic activation of JNK1 induced by mistletoe lectin II was inhibited by the addition of peptide aC-DEVD-CHO, but not by aC-YVAD-CHO. In addition, mistletoe lectin II induced apoptosis in a variety of cell types including Jurkat T cells, RAW 264.7 cells, HL-60 cells, DLD-1 cells, and primary acute myelocytic leukemic cells.

Apoptosis↗

PubMed2000

Effect of pentoxifylline on radiation response of non-small cell lung cancer: a phase III randomized multicenter trial.

PURPOSES: The objectives of this prospective clinical trial were to determine whether pentoxifylline improves the radiation response and survival in patients with non-small cell lung cancer. MATERIALS AND METHODS: From July 1993 through October 1994, 64 patients with histologically confirmed Stage I, II and III non-small cell lung cancer were randomly divided into pentoxifylline (Pento)+Radiotherapy (RT) group and RT alone group. Out of the 64 patients, only 47 patients who had measurable tumors on chest X-ray views were analyzed and divided into Pento+RT group (n=27) and RT alone group (n=20). Total tumor dose of 65-70 Gy was delivered as conventional fractionated radiation schedules. Pento was given to the patients 3 x 400 mg/day with a daily dose of 1200 mg during RT. RESULTS: Complete response (CR), partial response (PR), and stable in Pento+RT group were three (11%), 13 (48%), and 11 (41%), respectively, as compared with corresponding values of three (15%), 13 (65%), and four (20%) in the RT alone group. The median time to relapse in the Pento+RT group was 11 months which was 2 months longer than for the RT alone group (P>0.05). All the patients in both groups showed lower than or equal to grade 2 dysphagia, odynophagia, pulmonary fibrosis, and pneumonitis. The median survival was 18 months in the Pento+RT group and 7 months in the RT alone group. The 1-year survival rate was 60% in the Pento+RT group and 35% in the RT alone group, the 2-year survival rate was 18% in the Pento+RT group and 12% in the RT alone group. But these differences were not statistically significant (P>0.05). CONCLUSION: We concluded that Pento is a modestly effective radiation response modifier and provide benefit in the treatment of non-small cell lung cancer.

Aged↗

PubMed1999

Effect of ionizing radiation on the differentiation of ROS 17/2.8 osteoblasts through free radicals.

Although the acceleration of bone regeneration by radiation has been reported, the mechanisms of action of radiation on bone are unclear. The present results indicate that ionizing radiation-stimulated differentiation could result from the generation of reactive oxygen species during radiation exposure. The free radical release is considered as the most important mechanism of bone effect by radiation treatment. In addition, we report that radiation induced transient activation of c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) activation and the transcription factor, AP-1. The JNK and AP-1 activation is mediated with radiation-released free radicals in ROS 17/2.8 osteoblasts. These results indicate that ionizing radiation at a single dose of up to 5 Gray stimulates differentiation of ROS 17/2.8 osteoblasts via free radial release which may affect JNK/SAPK and AP-1 activities.

Animals↗