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991.
Pacini S Gulisano M Peruzzi B Sgambati E Gheri G Gheri Bryk S Vannucchi S Polli G Ruggiero M 《Cancer Detection and Prevention》2003,27(5):327-332
Human skin fibroblasts were exposed to 0.2 T static magnetic field generated by a magnetic resonance tomograph. After 1h exposure, cell morphology was modified in association with a concomitant decrease in the expression of some sugar residues of glycoconjugates. Study of cell proliferation and mitogenic signal transduction showed a decrease of thymidine incorporation and of second messenger formation. However, cell viability, assessed by colony forming assay, was unaffected. These results demonstrate that the static magnetic field generated by routinely used magnetic resonance tomograph induces alterations on human skin fibroblasts. 相似文献
992.
Cascinu S Catalano V Piga A Mattioli R Marcellini M Pancotti A Bascioni R Torresi U Silva RR Pieroni V Giorgi F Catalano G Cellerino R 《Cancer investigation》2003,21(5):701-707
Adjuvant 5-fluorouracil (5FU) and levamisole (Lev) have been considered standard treatment for stage III colon cancer patients. However, the uncertain contribution of Lev to the efficacy of treatment has led many oncologists to prefer the 5FU/leucovorin combination. To establish the role of Lev, we conducted a randomized trial comparing the 5FU/Lev combination with 5FU alone in patients with Dukes' C colon cancer. Patients with stage III colon cancer were randomized to receive 5FU alone (450 mg/m2 IV bolus daily for 5 days and then, beginning at day 28, weekly for 48 weeks) or the same plus Lev (50 mg orally three times/day for 3 days, repeated every 2 weeks for 1 year). From December 1994 to March 1998, 92 patients were assigned to receive 5FU/Lev, and 93 were assigned to receive 5FU alone. Leukopenia and hepatic toxicity were more frequent in patients receiving 5FU/Lev as compared with those receiving 5FU (respectively, p=0.003 and p=0.039), whereas other toxicities were equivalent and mild in both arms. After a median follow-up time of 48 months, 80 patients have had recurrences (40 in each arm) and no advantages in terms of disease-free survival and overall survival could be demonstrated for the combination arm. The addition of Lev to 5FU does not seem to be relevant for the clinical activity of this adjuvant regimen, whereas toxicity related to Lev should be considered when an adjuvant treatment for stage III colon cancer patients is proposed. 相似文献
993.
994.
BK virus (BKV), a human polyomavirus closely related to JC virus and Simian Virus 40, is ubiquitous in human populations worldwide. After primary infection, BKV establishes a lifelong latent infection in many organs. BKV transforms rodent cells to the neoplastic phenotype and is highly oncogenic in rodents. This review considers the oncogenic potential of BKV in humans and its possible involvement in human tumors. BKV sequences and T antigen (Tag) are detected in several types of human neoplasms, although the viral load is generally low, with less than one copy of the viral genome per cell. The possible causative role of BKV in human oncogenesis rests on the ability of BKV Tag to inactivate the functions of tumor suppressor proteins p53 and pRB family as well as on its ability to induce chromosomal aberrations in human cells. A 'hit and run' mechanism and secretion of paracrine growth factors by BKV Tag-positive cells, recruiting into proliferation neighboring and distant cells, are discussed as possible BKV pathogenic elements in human oncogenesis. 相似文献
995.
Luteinizing hormone increases human endometrial cancer cells invasiveness through activation of protein kinase A 总被引:4,自引:0,他引:4
Dabizzi S Noci I Borri P Borrani E Giachi M Balzi M Taddei GL Marchionni M Scarselli GF Arcangeli A 《Cancer research》2003,63(14):4281-4286
Endometrial cancer (EC) is a hormone-dependent cancer that currently represents the most frequent malignancy of the female reproductive tract. The involvement of steroid hormones in its etiology and progression has been reported. The possibility that even gonadotropins (GT) could play a role in the genesis and establishment of EC is supported by the fact that specific receptors for the GT luteinizing hormone/human chorionic GT (LH/hCG) have been detected in a high percentage of ECs, and their expression is apparently related to the cancer grading. However, the precise mechanisms by which GTs might exert their effect on EC is still obscure. The aim of this study was to determine the effects of LH/hCG on the invasion potential of EC cell lines and primary human EC cells. Human recombinant (hr) LH (and hCG) induced a significant increase in cell invasiveness through Matrigel-coated porous membranes in an EC human cell line Hec1A, which expresses the LH/hCG receptor. This effect turned out to depend on hrLH binding to its specific receptors and to the subsequent activation of protein kinase A (PKA). Moreover the hrLH-induced increase in Hec1A invasiveness relied upon a PKA-dependent functional activation of beta(1) integrin receptors, as well as the subsequent induction of matrix metalloproteinase-2 secretion in its active form. The same mechanisms were also found to be operative in primary EC cells. In fact, a significant percentage of primary ECs expressed the LH/hCG receptor, and hrLH addition to primary EC cells, which expressed the specific receptors produced an increase in cell invasiveness only in those tumor cells possessing the specific receptors. This effect was also dependent on PKA activity. We conclude that LH/hCG can regulate EC cells invasiveness, and this result provides a rationale for the use of inhibitors of LH secretion such as GnRH analogues in the treatment of EC. 相似文献
996.
Gastrointestinal stromal tumors: should they be treated with the same systemic chemotherapy as other soft tissue sarcomas? 总被引:4,自引:0,他引:4
997.
998.
Tarella C Cuttica A Vitolo U Liberati M Di Nicola M Cortelazzo S Rosato R Rosanelli C Di Renzo N Musso M Pavone E Santini G Pescarollo A De Crescenzo A Federico M Gallamini A Pregno P Romano R Coser P Gallo E Boccadoro M Barbui T Pileri A Gianni AM Levis A 《Cancer》2003,97(11):2748-2759
BACKGROUND: The objective of the current study was to evaluate in a multicenter setting the feasibility and efficacy of a high-dose sequential (HDS) chemotherapy regimen that combined intensive debulking and high-dose therapy (HDT) with peripheral blood progenitor cell (PBPC) autografting in patients with refractory or recurrent Hodgkin lymphoma (HL). METHODS: Data were collected from 102 patients with HL who were treated with the HDS regimen at 14 centers associated with the Intergruppo Italiano Linfomi. Twenty-four patients had primary refractory HL, 59 patients had their first recurrence of HL (within 1 year in 32 patients and > 1 year in 27 patients), and 19 patients had multiple disease recurrences. The HDS regimen included the sequential delivery of high-dose (hd) cyclophosphamide with PBPC harvesting, methotrexate, etoposide, then HDT (usually hd mitoxantrone plus L-phenylalanine mustard) with PBPC autografting. In addition, radiotherapy was delivered to 36 patients at sites of bulky or persistent disease. RESULTS: Ninety-two patients (90%) completed the HDS program. There were five toxic deaths (treatment-related mortality rate, 4.9%) and six secondary malignan cies (five patients developed myelodysplastic syndrome/acute myelogenous leukemia, and one patient developed colorectal carcinoma). At a median follow-up of 5 years, the 5-year overall survival (OS) and event-free survival (EFS) projections were 64% (95% confidence interval [95% CI], 54-74%) and 53% (95% CI, 43-63%), respectively. Patients with their first recurrence had the most favorable outcome, with 5-year OS and EFS projections of 77% (95% CI, 66-88%) and 63% (95% CI, 50-76%), respectively. There were no significant differences between patients with early first recurrence and late first recurrence. The poorest outcome was observed in patients with refractory HL, with 5-year OS and EFS projections of 36% (95% CI, 16-55%) and 33% (95% CI, 14-52%), respectively. Patients who received HDS chemotherapy after multiple recurrences had an intermediate outcome. Multivariate analysis showed that refractory disease and systemic symptoms at the time of initial presentation were associated significantly associated with poor OS and EFS. CONCLUSIONS: The use of HDS chemotherapy for patients with refractory and/or recurrent HL is feasible at the multicenter level. The combination of intensive debulking and HDT with PBPC autografting offers a good chance of prolonged disease free survival for patients with their first recurrence of HL. 相似文献
999.
Cuttica A Zallio F Ladetto M Di Nicola M Caracciolo D Magni M Marinone C Dell'Aquila M Rosace M Pileri A Boccadoro M Gianni AM Tarella C 《Cancer》2003,98(5):983-992
BACKGROUND: The goal of the current study was to evaluate the impact of presentation with an age-adjusted International Prognostic Index (aaIPI) score of 2 or 3 on patients with high-risk aggressive lymphoma who are treated with frontline intensive chemotherapy and autografting. METHODS: Sixty-nine consecutive patients (median age, 40 years) with either B-cell (n = 60) or non-B-cell (n = 9) aggressive lymphoma were treated with high-dose sequential (HDS) chemotherapy and peripheral blood progenitor cell (PBPC) autografting. The patients who were examined had poor prognoses, with aaIPI scores of 2 (n = 37) or 3 (n = 32). The original treatment regimen, sequential delivery of cyclophosphamide, methotrexate, and etoposide, followed by PBPC autografting (o-HDS), was used in the first 32 patients; the program was intensified by the addition of a course of high-dose cytosine arabinoside (C-HDS) in the next 37 patients. RESULTS: There were 4 toxicity-related deaths-2 in each aaIPI subgroup (treatment-related mortality, 5.8%). The complete remission rate was significantly higher among patients with an aaIPI score of 2 (n = 32 [86%]) compared with those with an aaIPI score of 3 (n = 13 [41%]; P < 0.001). Patients with an aaIPI score of 2 had significantly better outcomes than did patients with an aaIPI score of 3 in terms of both overall survival (78% vs. 34% at 8 years; P < 0.001) and event-free survival (72% vs. 28% at 8 years; P < 0.001). Similar results were observed when the analysis was limited to the 60 patients with B-cell-derived lymphoma. No significant differences in outcome between patients receiving o-HDS and patients receiving C-HDS were observed. Multivariate analysis demonstrated that an aaIPI score of 3 was the only parameter that was significantly associated with poor overall and event-free survival. CONCLUSIONS: Age-adjusted International Prognostic Index score is applicable to patients with aggressive lymphoma who are treated with frontline intensive chemotherapy and autografting. In addition, upfront use of HDS chemotherapy appears to be beneficial to patients with an aaIPI score of 2 but not to those with an aaIPI score of 3. 相似文献
1000.