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Even if template sequence of hTR played an essential role in telomere binding, a 326 nucleotide fragment of hTR containing template, pseudoknot, and CR4-5 domains is critical for both binding with telomeric DNA and reconstitution of telomerase activity. A functional study with antisense oligonucleotides suggested that targeted disruption of the template region efficiently abrogated both telomeric DNA binding and telomerase activity, whereas disruption of the CR4-5 region induced only loss of telomerase activity. hTR interacts with telomeric DNA via structural region composed of the template, pseudoknot, and CR4-5 domains, however, each structural domain plays a distinct role in telomere binding and telomerase activity reconstitution.

We evaluated the efficacy and tolerability of a combination chemotherapy including infusional fluorouracil (5-FU), etoposide, and cisplatin (FEP) in 89 patients with advanced/relapsed gastric cancer. Primary endpoints were progression-free and overall survival. Secondary endpoints were response rates, response duration, and toxicity. The treatment schedule was as follows: 5-FU 1,000 mg/m2 and etoposide 100 mg/m2 were administered on 3 consecutive days and cisplatin at 80 mg/m2 was administered on day 2, and repeated every 3 weeks. The median times to progression and overall survival were 4 and 8 months, respectively. One-year progression-free and overall survival rates were 10% and 33%, respectively. The overall response rate for 25 eligible patients with measurable disease was 20% (5/25, complete response 2, partial response 3) with median response duration of 7 months. Median actual dose intensities of 5-FU, etoposide, and cisplatin were 700 mg/m2/wk, 70 mg/m2/wk, and 21 mg/m2/wk, respectively. Median relative dose intensities of 5-FU, etoposide, and cisplatin were 0.70, 0.70, and 0.63, respectively. In conclusion, the FEP regimen was found to produce therapeutic results similar to those of other combination chemotherapeutic studies and to have an acceptable toxicity. This regimen could be used as one of the options for advanced gastric cancer chemotherapy in patients unsuitable for doxorubicin-based regimens.

Among the many biological characteristics of cancer, matrix-metalloproteinases (MMPs) are essential for tumor invasion and metastasis. To test the possibility of ex vivo model as a therapeutic guideline for MMP inhibitor (MMPI) treatment, we evaluated IC50 of the gabexate mesylate against MMP-9. Thirty-four paired normal and gastric cancer tissues were tested to measure the IC50 of the gabexate mesylate. MMP-9 activity was measured by zymography. Both MMP-9 expression (p=0.04) and IC50 (p=0.02) were higher in cancer than normal tissues. IC50 of the cancer tissues was higher than paired normal tissues especially in cases with large tumor (> or =5 cm) (p=0.03), higher T-stage (p=0.04), lymph node metastasis (p=0.04) and advanced stage (p=0.04). In cancers extending beyond submucosa or in diffuse/mixed type, a tendency of higher IC50 was observed than tumors confined to submucosa or intestinal type cancer despite similar MMP-9 activity between the groups. Patients with high IC50 showed poorer prognosis than patients with low IC50 in curatively-resected group. In multivariate analysis, high IC50 was suggested as an independent prognostic factor. We were able to differentiate the high risk patients using IC50 of gabexate mesylate in ex vivo model. This model can be applied in detecting patients with poor prognosis and patients who may benefit from MMPI treatment.

Background: The treatment options for the 10-20 per cent of patients with gastric cancer who present with peritoneal dissemination are extremely limited and no standard approach exists., Methods: The feasibility of using intraperitoneal chemotherapy to treat gastric cancer with intra-abdominal gross residual lesions after palliative gastrectomy with maximal cytoreduction was investigated. Early postoperative intraperitoneal chemotherapy started on the day of operation with 5-fluorouracil 500 mg/m2 and cisplatin 40 mg/m2 (days 1-3) over a 4-week interval., Results: Of the 53 patients enrolled between July 1994 and December 1998, 49 were eligible. The progression-free survival (PFS) was 7 months and the overall survival was 12 months. In multivariate analysis, performance status was the only significant defining factor for PFS (P = 0.009). The predominant toxicity was neutropenia and nausea/vomiting. The relative dose intensity of 5-fluorouracil and cisplatin was 89 and 63 per cent respectively., Conclusion: Performance status emerged as a major determining factor for prognosis and patient selection for early postoperative intraperitoneal chemotherapy in patients with advanced gastric cancer after maximally cytoreductive surgery.

Purpose: We evaluated the treatment efficacy including survival and recurrence, and factors associated with recurrence in osteosarcoma patients treated with preoperative chemotherapy, surgery, and adjuvant chemotherapy., Materials and Methods: Forty nine patients with osteosarcoma were treated with preoperative chemotherapy with intra-arterial cisplatin and adriamycin infusion for 3 cycles, followed by surgery. According to the pathologic response, if tumor was necrotized more than 90%, the same adjuvant chemotherapy was reintroduced for 3 cycles, and if the response was not enough, then the salvage regimen was introduced. Plain chest film and chest CT scan were taken monthly and every 3 months, respectively. When tumor recurred, the metastasectomy was performed whenever possible., Results: Forty three patients were evaluable with amedian follow up of 53 months. Five-year disease-free and overallsurvival rate was 47.0% and 66.9%, respectively. The recurrence was observed in 22 patients (51.2%) with median time of 12.5 months. Baseline alkaline phosphatase (ALP) was the only significant factor for recurrence (p=0.03) and the patients with the possibility of metastasectomy recurrence showed higher post-relapse survival compared to other treatment modalities (26 momths vs 5~12 months)., Conclusion: These results indicates that pre- and postoperative chemotherapy with intra-arterial cisplatin and adriamycin infusion showed comparable treatment efficacy and acceptable toxicities.

We investigated the dose-related effect of the 5-fluorouracil (5-FU)/leucovorin regimen on survival in 139 colon cancer patients with Dukes' B2 and C2 stage disease. Chemotherapy consisted of 400 mg/m(2) of 5-FU and 20 mg/m(2) of leucovorin injected daily for 5 days in every 4 weeks for a maximum of 12 cycles. The total dose of 5-FU administered per body surface area had a significant effect on the 5-year disease-free survival and 5-year overall survival in stage B2 and C2 colon cancer patients (P=0.0018, P=0.0011). Analysis with reference to the median DSDI demonstrated that there was a significant difference in 5-year survival in Dukes' C2 (P=0.0016), but survival was not affected by the dose intensity. Multivariate analysis demonstrated that only the total dose of 5-FU administered per surface area affected the 5-year disease-free survival and 5-year overall survival (P=0.0016, P=0.0007, respectively). It can be concluded that the total dose of 5-FU administered is important in planned dosage schedule of adjuvant chemotherapy in colon cancer.

Background: The authors evaluated the efficacy of adjuvant chemotherapy with 5-fluorouracil (5-FU) plus doxorubicin in gastric carcinoma after D2-3 curative resection. They also evaluated the effect of dose-related factors (delivered total dose/m(2), actual dose intensity [ADI], relative dose intensity [RDI]) of this regimen on patient survival., Methods: A total of 301 patients with Stage II to IV (en bloc resected T4b; 1984 American Joint Committee on Cancer staging) were accrued between 1984 and 1996. Chemotherapy was started within 4 weeks of surgery according to the following schedule: intravenous bolus injection of doxorubicin 40 mg/m2 every 3 weeks for 12 cycles and 5-FU 400 mg/m2 weekly for 60 weeks. The toxicity and survival were evaluated., Results: The median follow-up duration was 58 months. Sixty-four percent of the total patients and 71.7% of the patients who did not experience recurrence during the chemotherapy finished the protocol completely with acceptable toxicities. The 5- and 10-year disease free survival rates of total 301 patients were 58.4% and 46.5%, and the overall survival rates were 62.1% and 50.5%, respectively. Treatment completion group showed survival benefit over the early termination group in 5-year survival (75.2% vs. 52.9%; P = 0.0005). The median ADI of 5-FU and doxorubicin were 349 and 11 mg/m2/week, and the median RDIs of 5-FU and doxorubicin were 0.87 and 0.83, respectively. Multivariate analysis demonstrated that completion of chemotherapy is an independent prognostic factor of both disease free and overall survival. However, ADI and RDI did now show any effect on survival., Conclusions: Adjuvant chemotherapy with 5-FU plus doxorubicin for 60 weeks after D2-3 dissection induced promising survival duration with acceptable toxicities. Full administration of the planned dosage of the combined drugs is recommendable as opposed to early termination of the chemotherapy in gastric carcinoma., (Copyright 2001 American Cancer Society.)

Cisplatin-based chemotherapy is being tried in the treatment of nonoperable cases of non-small-cell lung cancer (NSCLC). However, the prognosis is unfavorable and to improve survival, clinical studies using various combinations of a variety of drugs as well as experimental material are in progress. We compared the efficacy and toxicities of combination chemotherapy using different doses of vinorelbine and ifosfamide with a constant dose of cisplatin in this study. Patients diagnosed with inoperable stage III or IV NSCLC between June 1997 and December 1998 were included. Cisplatin was administered at a constant dose of 80 mg/m2 on day 5, whereas vinorelbine on days 1 and 5 and ifosfamide on day 5 were administered in one of two different doses. In arm A, vinorelbine 25 mg/m2 and ifosfamide 3.0 g/m2 were administered. In arm B, vinorelbine 20 mg/m2 and ifosfamide 2.5 g/m2 were administered. Also, we reviewed for phase II and III studies that test 1) cisplatin, 2) vinorelbine monotherapy, and 3) vinorelbine/cisplatin/ifosfamide combination chemotherapy for stage IIIb-IV non-SCLC. Summation dose intensity (SDI) was calculated in each published and current study. Twenty patients in arm A and 35 patients in arm B were available for evaluation. There was no difference in patient activity, pathologic diagnosis, and differentiation or stage between the two arms. The median number of cycles was four in both arms. The response rate was 50% in arm A and 30% in arm B. The median survival times for arm A and B were 40 and 42 weeks, respectively, whereas the SDI was 1.94 and 1.7, respectively. More than grade III leukopenia was observed in 28.9% in arm A, which is more frequent than the 17.2% in arm B. There was a significant correlation between the SDIs and response rates and median survival (r2 = 0.629, p = 0.001; r2 = 0.453, p = 0.001, respectively). Although the follow-up period is relatively short, the survival time was similar in both arms. Because a high response rate may not be followed by a high survival time in combination chemotherapy of NSCLC, further studies on the appropriate dose of individual agents with regard to the relationship between response rate, severity, and incidence of toxicities and survival rate should be carried out.