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1.
In a previous study of acute leukemia, we have shown that WT1 gene mutations occur in both myeloid and biphenotypic subtypes, where they are associated with refractoriness to standard induction chemotherapy. We have now extended this study to a total of 67 cases (34 acute myeloid leukemia [AML], 23 acute lymphoblastic leukemia [ALL], 10 acute undifferentiated leukemia [AUL]/biphenotypic) and find that WT1 mutations occur in 14% of AML and 20% of biphenotypic leukemia, but are rare in ALL (one case). In contrast to the findings in Wilms' tumor, where mutations in the WT1 gene usually behave according to Knudson's two hit model for tumor suppressor genes, seven of eight leukemia-associated WT1 mutations are heterozygous, implying a dominant or dominant-negative mode of action in hematopoietic cells. In AML, the presence of a WT1 mutation is associated with failure to achieve complete remission and a lower survival rate. These data (1) confirm that WT1 mutations underlie a similar proportion of cases of AML to that seen in Wilms' tumors and (2) show for the first time that WT1 mutations can contribute to leukemogenesis of lymphoid as well as myeloid origin, suggesting that its normal role in hematopoiesis lies at a very early progenitor stage. The relationship of WT1 mutation to chemoresistance merits further investigation.  相似文献   

2.
Veno-occlusive disease of the liver (VOD) is an important complication in children with Wilms' tumour. Although in most patients this complication resolves uneventfully, fatal cases have been reported. Several observations strongly suggest that actinomycin-D is the likeliest cause of VOD in Wilms' tumour, but VOD seems to be rather uncommon in other malignancies treated with chemotherapy including actinomycin-D. The present case of VOD and the review of the literature stress the pathogenetic and clinical implications of VOD in the presence of a Wilms' tumour treated with actinomycin-D, originating in the right kidney. Greater awareness of this 'predisposing factor' may alert paediatricians to the presence of minimal signs of the syndrome.  相似文献   

3.
Mutations of the p53 tumor suppressor gene occur frequently in a variety of adult-onset tumors, including colon, breast, lung, and brain, yet are infrequently identified in pediatric malignancies. Wilms' tumor, a common solid tumor of childhood, can be associated with mutations of the WT1 gene. Alterations of the p53 gene have been shown to modulate the ability of WT1 to transactivate its targets. Although positive p53 immunostaining has been demonstrated in Wilms' tumors, the correlation to p53 gene mutations is not clear. We examined Wilms' tumor samples for p53 mutations utilizing polymerase chain reaction-single-strand conformation polymorphism analysis and single-strand DNA sequencing. Mutations in the coding region of the p53 gene were demonstrated in 2 of 21 (9.5%) Wilms' tumors. Each mutation yielded a substitution of amino acid residues. One mutation was located in exon 6 and the other in exon 7. Both mutations were found in tumors from patients with advanced stage disease. Focal anaplasia was demonstrated in one of these tumors. Our data suggest that although p53 mutations occur infrequently in Wilms' tumor, they may be associated with advanced disease.  相似文献   

4.
PURPOSE: Patients with Wilms' tumors (WT) who carry constitutional mutations in the WT1 gene have been described in case reports and small case series. We sought to determine the frequency of constitutional WT1 mutations in a larger cohort, and to identify clinical manifestations associated with the risk for carrying a WT1 mutation. METHODS: We collected clinical data and blood samples from 201 patients with a history of WT. Southern blot analysis, single-strand conformation polymorphism (SSCP) analysis, and direct DNA sequencing were performed on DNA isolated from peripheral-blood lymphocytes from each patient. Odds ratios (ORs) for the carriage of a germline mutation of the WT1 gene were calculated for patients who had specific clinical risk factors compared with those who did not. RESULTS: Of 201 patients with WT in the cohort, eight patients were carriers of mutations in the WT1 gene. Six of the eight mutations were protein-truncating nonsense mutations. None of 56 patients with isolated unilateral WT was a carrier. The OR of carrying a WT1 mutation was elevated for patients with genitourinary anomalies (OR19.3; P < .002). Seven of 28 boys with WT with cryptorchidism carried WT1 mutations. No increased risk was observed for patients with nephrogenic rests, bilateral tumors, history of secondary cancers, or family history of WT. CONCLUSION: Germline WT1 mutations in patients with WT are associated with genitourinary anomalies, especially cryptorchidism and/or hypospadias. Patients with WT and no genitourinary anomalies are at low risk for carrying a WT1 mutation. Constitutional WT1 mutations that encode truncated WT1 proteins may predispose to the development of cryptorchidism, hypospadias, and WTs.  相似文献   

5.
6.
BACKGROUND: Controversy exists as to the treatment regimen necessary to best provide optimal local control for inflammatory breast carcinoma (IBC). This study was conducted to determine if mastectomy combined with radiotherapy offered any advantages over radiotherapy alone in patients with IBC who had been treated with doxorubicin-based combination chemotherapy. METHODS: A retrospective review of 178 women treated for IBC on doxorubicin-based multimodality therapy protocols between January 1974 and September 1993 was performed. Clinical and histologic response to treatment, time to local recurrence, survival, and ultimate control of local disease were analyzed. Kaplan-Meier analysis was used to examine survival and relapse times, and Fisher's exact test was used to test differences in treatment outcomes. Significance was determined at p < or = 0.05. RESULTS: Median follow-up was 89 months (range 22 to 223 months). Locoregional disease persisted in seven patients and recurred in 44 patients who had been rendered disease free at a median time of 10 months. The mortality rate after a local recurrence (LR) was 98%, and all patients but one with LR developed systemic metastases. Response to induction chemotherapy influenced the incidence of LR, and the amount of residual disease found on histologic examination of mastectomy specimens was highly prognostic for local failure. Patients who underwent mastectomy in addition to radiotherapy had a lower incidence of LR than did patients who received radiotherapy alone (16.3% vs. 35.7%, p = 0.015). CONCLUSIONS: The addition of mastectomy to combination chemotherapy plus radiotherapy improved local control in patients with IBC. The addition of mastectomy to chemotherapy plus radiotherapy improved distant disease-free and overall survival in patients with a clinical complete or partial response to induction chemotherapy. Patients who had no significant response to induction chemotherapy received no survival or local disease-control benefit from the addition of mastectomy to their treatment regimen. These patients should be considered for entry into clinical trials of new treatment regimens.  相似文献   

7.
250 patients with clinical stage 1 non-seminomatous germ cell tumours of the testis (NSGCT 1) were included into a prospective multicentre protocol during 1990-1994 and treated according to three risk strata: patients without tumour cell invasion of vascular structures in the testis (VASC-) and elevated serum AFP levels (AFP+) at orchiectomy were considered low risk (LR) and only observed closely. VASC- and AFP- or VASC+ and AFP+ patients were presumed intermediate risk (IR) and pathologically staged (PS) by retroperitoneal lymph node dissection (RPLND). VASC+ and AFP-patients were regarded as high risk (HR) and received adjuvant chemotherapy (PEB x 3). At a median observation time of 40 (7-68) months, all patients were alive and without evidence of active germ cell cancer. The actuarial relapse rate in the 106 LR patients was 22%, and 70% (14/20) had elevated serum tumour markers at relapse. One of 32 (3%) HR patients relapsed with a resectable retroperitoneal mature teratoma despite adjuvant chemotherapy. Only 14% of the 99 IR patients who underwent RPLND had PS2 disease, and the actuarial relapse rate in 85 PS1 patients was 18%. This multicentre study demonstrated that excellent therapeutic outcome is possible when 18 comparatively small urological and oncological centres follow a strict and formal cancer care programme. The useful prognostic effect of VASC was once again verified. Pathological staging by RPLND in NSGCT1 is, in our opinion, not necessary, with presumed low-risk patients offered surveillance and high-risk patients offered adjuvant chemotherapy.  相似文献   

8.
9.
Basic fibroblast growth factor (bFGF) is a potent angiogenic peptide implicated in the growth and metastasis of solid tumors. Elevated concentrations of bFGF have been found in the urine of patients with bladder, prostate, and renal tumors. Furthermore, urinary bFGF levels have been shown to correlate with extent of disease. In order to test the utility of urinary bFGF as a Wilms' tumor marker, we measured bFGF levels in preoperative and postoperative urine samples from 97 patients with Wilms' tumor. Preoperative urine samples (n = 97), early postoperative samples obtained from 1 to 3 weeks after surgery (n = 43), and late postoperative samples obtained from 1 to 6 months after surgery (n = 66) were collected from Wilms' tumor patients at 30 institutions between 1989 and 1993. Urine samples from age-matched controls (n = 17) were also obtained. The bFGF levels were determined in duplicate by a competitive sandwich ELISA capable of measuring bFGF at the pg/ml level. Samples were normalized for creatinine content. Urinary bFGF was elevated in 42% of preoperative samples when compared to controls (>90th percentile of normal). Patients with stage III, IV, and V disease had significantly higher preoperative levels of urinary bFGF when compared to patients with stage I and II disease (P < 0.01). Patients with relapse or persistent disease had significantly elevated late postoperative bFGF levels when compared to disease-free patients and controls (P < 0.05). Thus, in patients with Wilms' tumor, elevated preoperative urinary bFGF levels raise the suspicion of aggressive disease while elevated postoperative levels may indicate recurrence or persistence of disease. These data suggest that bFGF is a biological marker for Wilms' tumor and may have a role in the evaluation of patients with this disease.  相似文献   

10.
The ability of oestrogen and progesterone receptor (ER and PgR, respectively) status to discriminate recurrence-free survival (RFS) among a cohort of consecutively accrued 952 postmenopausal patients has been studied. None of the cohort members investigated were treated with adjuvant therapy. Using a graduated scale of receptor status [low, intermediate and high receptor levels (< 10 vs. 10-107 vs. > or = 108 fmol/mg cytosol protein, respectively)] instead of the more commonly used dichotomous subdivision (positive vs. negative), ER level significantly discriminated between groups of patients with long vs. short RFS. Contrary to our expectations, patients with highest ER levels have as poor a prognosis as ER-negative patients, while patients with intermediate ER levels have longest RFS. The group of patients with ER levels > or = 108 fmol/mg cytosol protein comprises 47% of the cohort. The independent significance of overexpression of ER as a prognostic factor among this patient group is demonstrated in multivariate analysis where ER level is more significant than either grade of anaplasia or tumour size. PgR status did not significantly predict RFS among these patients. While the highest ER levels predispose for poorer prognosis among postmenopausal patients, it is precisely this group that experiences greatest benefit from adjuvant treatment with tamoxifen. Thus, patients who might otherwise go untreated due to their node-negative status can be readily identified and offered adjuvant treatment.  相似文献   

11.
PURPOSE: The fraction of cells that incorporate 3H-thymidine (3H-dT labeling index [3H-dT LI]) proved to be a prognostic indicator in patients with node-negative and node-positive resectable breast cancers treated with locoregional treatment alone or with adjuvant combination chemotherapy. In this study, we assessed the prognostic role of 3H-dT LI alone and in association with other pathologic and biologic variables in a series of 249 women with node-positive breast cancers treated with adjuvant endocrine therapy. PATIENTS AND METHODS: All patients were postmenopausal, had resectable estrogen receptor-positive (ER+) tumors, and had received tamoxifen for at least 1 year after radical or conservative surgery plus radiotherapy. The median follow-up duration was 48 months. RESULTS: The 4-year relapse-free survival (RFS) rates were significantly lower for patients with large tumors (> 2 cm), with more than three positive lymph nodes, with low (< 150 fmol/mg proteins) ER content, without progesterone receptors (PgRs), or with rapidly proliferating tumors. 3H-dT LI provided prognostic information independent of axillary node involvement, ER content, PgR status, and tumor size, with an estimated odds ratio (OR) higher than that of tumor size, lymph node involvement, or ER concentration. In addition, 3H-dT LI and PgR in association were able to identify patients with different risks of relapse within subsets of tumors with less or more than three positive nodes. CONCLUSION: 3H-dT LI provides prognostic information complementary to PgR, tumor size, lymph node involvement, and ER content in the prediction of RFS of postmenopausal patients with node-positive, ER + resectable tumors treated with adjuvant hormone therapy.  相似文献   

12.
A total of 15 patients with relapsed Wilms' tumor were treated with carboplatin as a single agent. There were six females and nine males, aged between 2 and 9 years (median:5). The treatment consisted of carboplatin given I.V. as a single agent at a dose of 550 mg/m2 over 1 hour every 3 weeks. There were four (26%) complete responses, four (26%) partial responses, one stable disease, and six with progressive disease. In all patients a total of 56 courses were given and the toxicities found were leukopenia and thrombocytopenia. The overall response rate was encouraging and the toxicity was acceptable and reversible.  相似文献   

13.
PURPOSE: In patients with stage IV melanoma, durable responses have been reported with treatment regimens that involve high-dose interleukin-2 (IL-2). We analyze long-term results of 631 melanoma patients from 12 institutions who had received IL-2 alone, in combination with interferon alfa 2a or 2b (IFNalpha), or with cytotoxic drugs. METHODS: Case records that contained pretreatment parameters, response data, and updated survival information were collected. After univariate analysis, the multivariate evaluation of the impact of pretreatment parameters on response and survival was performed by logistic regression and Cox's regression, respectively. RESULTS: Patients were divided into four groups according to treatment: IL-2 alone (n=117), IL-2 and chemotherapy (n=49), IL-2 and IFNalpha (n=153), and IL-2, chemotherapy, and IFNalpha (n=312). The median survival of all patients was 10.5 months and the 2- and 5-year survival rates were 19.9% and 10.4%, respectively. Independent prognostic factors for response and survival were entirely different, treatment group being the only significant factor for response, and serum lactate dehydrogenase (LDH), metastatic site, and performance predicting survival. The addition of IFNalpha to IL-2 was associated with prolonged survival, but the effect of additional chemotherapy was less obvious. CONCLUSION: Serum LDH, metastatic site, and performance status are useful stratification factors for randomized trials in metastatic melanoma. The improved long-term survival rates observed in melanoma patients treated with IL-2/IFNalpha-containing regimens are notable in contrast to the reported 5-year survival rates of 2% to 6% achieved with chemotherapy, but because selection bias cannot be ruled out, the impact of IL-2, as well as all other components of the treatment regimens, on survival needs to be confirmed in prospective randomized trials.  相似文献   

14.
BACKGROUND: Patients with TNM stage IV non-small-cell lung cancer have short survival times. Previous controlled studies comparing chemotherapy and supportive care for the treatment of this type of cancer have not given consistent results, have included patients with different disease stages, and have rarely reported drug dose intensity. PURPOSE: The present trial was designed to assess the safety and the effect on survival of supportive care alone versus chemotherapy with cisplatin, cyclophosphamide, and mitomycin combined with appropriate supportive care in patients with stage IV non-small-cell lung cancer. METHODS: Patients (n = 102) with stage IV non-small-cell lung cancer were randomly assigned to one of two treatment regimens. The combined modality group (52 patients) received supportive care along with cisplatin (75 mg/m2), cyclophosphamide (400 mg/m2), and mitomycin (10 mg/m2) given intravenously at 3-week intervals. The supportive care group (50 patients) received supportive care alone. Randomization was stratified on the basis of histology (squamous versus nonsquamous cell carcinoma), performance status (Karnofsky), and weight loss (during the 6 months preceding randomization). The two groups were well matched for age and sex. Survival analysis was performed after the last patient died. RESULTS: The median number of chemotherapy cycles was 3.5 per patient. Mean weekly delivered doses of drugs were as follows: cisplatin, 22.1 mg/m2; cyclophosphamide, 118 mg/m2; and mitomycin, 2.9 mg/m2. Toxic effects due to chemotherapy were generally mild, but peripheral neuropathy and hematologic and renal toxic effects were observed. In the supportive care group, mean survival was 6.1 months (median, 4.0 months); six patients lived at least 12 months and two lived at least 18 months. In the combined modality group, mean survival was 11.3 months (median, 8.5 months); 20 patients lived at least 12 months, 13 lived at least 18 months, and five lived at least 24 months. Difference in survival was statistically significant (P < .0001). Survival was directly related to initial performance status in both groups (P < .01) and was significantly (P < .01) longer for patients with squamous cell carcinoma than for those with nonsquamous cell carcinoma. CONCLUSIONS: The combination of supportive care and cisplatin-cyclophosphamide-mitomycin therapy offers a survival advantage over supportive care alone in patients with advanced non-small-cell lung cancer. IMPLICATIONS: Metastatic non-small-cell lung cancer, generally considered to be unresponsive or marginally responsive to chemotherapy, can be treated with chemotherapy, with an expectation of prolonging patient survival. Although the results of the present study are encouraging, clinical research should continue to be directed toward developing more effective treatments for this disease.  相似文献   

15.
To assess the efficacy of treatment of parasitological excretion of cysts and trophozoites and symptoms of patients with giardiasis, a systematic review of published randomized clinical trials was conducted through extensive searches in Medline, Embase and Current Contents from 1966 till 1996 as well as manual reviews of 28 journals. The methodological quality of all trials was assessed by guidelines of the Cochrane Collaboration. Thirty-one trials were included, only one of which had no serious methodological flaws. The mean score of parasitological examination was 4.8 out of a possible 15. There was a considerable effect in cure rate of treatment versus placebo (odds 9.3, 95% CI 4.69-18.4), but all 3 trials in this comparison had serious flaws. Metronidazole treatment over more than 3 days seems to achieve a better parasitological cure rate than other long treatment courses (pooled odds 2.6, 95% 1.7-3.8), but trials are clinically and statistically heterogeneous. Single-dose therapy is as effective as longer treatment courses (pooled odds 0.67, 95% 0.31-1.44). Within the single-dose regimens tinidazole (2 g) reaches a higher parasitological cure rate than other short therapies (pooled odds 55, 95% CI 3.7-8.3) with relatively few side-effects. Placebo-controlled trials with parasitological and clinical outcomes are needed.  相似文献   

16.
FA Greco  JD Hainsworth 《Canadian Metallurgical Quarterly》1997,11(1):27-36; discussion 41, 44, 49
The management of patients with non-small-cell lung cancer (NSCLC) is still evolving. Newer third-generation chemotherapy (paclitaxel [Taxol]-based; vinorelbine [Navelbine]/ cisplatin [Platinol]) is more effective than second-generation cisplatin-based chemotherapy for patients with stage IIIB and IV disease. The combined use of cisplatin-based chemotherapy with sequential or concurrent radiation therapy has improved the survival of patients with unresectable stage IIIA disease. Neoadjuvant cisplatin-based chemotherapy has improved the survival of patients with resectable stage IIIA disease compared to surgery alone. Combined-modality therapy is a fertile area of innovative clinical investigations for the majority of stage III resectable and potentially curable NSCLC patients, as well as those with locally advanced unresectable stage III disease. We expect therapy to substantially improve over the next few years. Cooperative groups should move quickly to incorporate third-generation chemotherapy into large randomized trials in order to redefine the standard of therapy for patients with this disease.  相似文献   

17.
In acute myelogenous leukemia (AML) intensive postremission treatment is needed for an optimal result. However, it is not known how long the treatment should last and how many courses are necessary. The object of this prospective study was to compare four and eight intensive chemotherapy cycles in the treatment of adult de novo AML. In a multicenter study, 248 consecutive patients, aged from 16 to 65 years, were treated with intensive induction treatment. The patients in remission after two courses were randomized to receive either two (short arm) or six (long arm) additional intensive cycles of chemotherapy. The median follow-up time of the living patients is 68 months. Of the patients, 77% achieved complete remission, and 36% of all patients survived for 5 years. Seventy-three patients were randomized to the short arm and 66 to the long arm. There was no significant difference in the relapse-free survival (median 21 months vs 17 months) or overall survival (43 months vs 39 months) between the short and long arms, respectively. Treatment-related deaths occurred in 31 patients (13%), 11 of them in first remission. More than one-third of the patients survived for 5 years. It seems probable that the first few months after diagnosis are decisive for the prognosis if the chemotherapy is intensive, and further treatment cannot markedly influence the outcome.  相似文献   

18.
PURPOSE: The current study investigates the frequency and outcome of secondary malignancies in patients treated for testicular cancer at Hannover University Medical School between 1970 and 1990. PATIENTS AND METHODS: One thousand twenty-five patients with a median follow-up duration of 61 months (range, 12 to 240) were included in the analysis. Follow-up was complete in 1,018 patients (99%). Histology was seminoma in 324 patients (38.7%) and nonseminomatous germ cell tumor in 624 patients (61.3%). At the time of median follow-up, 814 patients (79.9%) were alive. RESULTS: Fourteen patients developed a secondary neoplasm (cumulative incidence, 1.38%; 95% confidence interval [CI], 0.75 to 2.30); 13 patients had solid tumors and one had secondary lymphoblastic leukemia with a t(4; 11) translocation including band 11q23. None of 224 patients on surveillance strategy (with or without retroperitoneal lymph node dissection [RPLND]) developed a second neoplasm, compared with four of 413 patients (0.97%; 95% CI, 0 to 1.9) after cisplatin-based chemotherapy (not significant) and nine of 332 patients (2.7%; 95% CI, 0.9 to 4.5) after radiotherapy (P = .02). The cumulative incidence of a secondary neoplasia of 1.76% (95% CI, 0.97 to 2.94) in patients treated by radiotherapy and/or chemotherapy was significantly higher compared with patients on surveillance protocols (P = .03). Chemotherapy containing standard-dose etoposide did not increase the risk of occurrence of secondary neoplasms. A significantly elevated relative risk of 7.53 (range, 3.4 to 14.3) compared with the male German population was only found for patients treated by radiotherapy. CONCLUSION: Compared with patients who have other curable malignant tumors, an incidence of 1.38 of secondary neoplasms after a median follow-up duration of 61 months is low. The highest risk for secondary neoplasia after treatment of testicular cancer is associated with the use of radiotherapy. Following chemotherapy, no significantly elevated risk was observed. In conclusion, the benefits of curative treatment far outweigh the risk of secondary cancer in patients with malignant germ cell tumors.  相似文献   

19.
BACKGROUND: The aim of this trial was to compare the outcome achieved with neoadjuvant chemotherapy followed by radiotherapy to that achieved with radiotherapy alone for patients with locoregionally advanced undifferentiated or poorly differentiated nasopharyngeal carcinoma (NPC) meeting one of the following criteria: Ho's T3 disease, Ho's N2-N3 disease, or lymph node size > or =3 cm. METHODS: Between September 1989 and August 1993, 334 patients were enrolled in the study, with equal numbers of patients randomized to the neoadjuvant chemotherapy arm (CT arm) and the radiotherapy arm (RT arm). Neoadjuvant chemotherapy consisting of 2-3 cycles of cisplatin (60 mg/m2 on Day 1) and epirubicin (110 mg/m2 on Day 1) followed by radiotherapy was given to the CT arm. For radiotherapy, a dose of 66-74 gray (Gy) (median, 71 Gy) was delivered to the primary tumor and 60-76 Gy (median, 66 Gy) to the neck. Two hundred eighty-six eligible patients completed the treatment and were evaluable for treatment response (134 in the CT arm, 152 in the RT arm). All patients were included in the survival analysis based on the intention to treat. The median follow-up was 30 months for the whole cohort and 41 months for the surviving patients. RESULTS: Analysis of the 334 patients based on the intention to treat showed no significant difference in relapse free survival (RFS) or overall survival (OS) between the 2 treatment arms (3-year RFS rate: 48% in the CT arm vs. 42% in the RT arm, P = 0.45; 3-year OS rate: 78% vs. 71%, P = 0.57). In an efficacy analysis based on only the 286 evaluable patients, a trend of improved RFS favoring the CT arm was observed (3-year RFS rate: 58% vs. 46%, P = 0.053), with again no significant difference in OS (3-year OS rate: 80% vs. 72%, P = 0.21). In the subgroup of 49 patients with bulky neck lymph nodes >6 cm, improved RFS (3-year RFS rate: 63% vs. 28%, P = 0.026) and OS (3-year OS rate: 73% vs. 37%, P = 0.057) were observed, favoring the CT arm. CONCLUSIONS: This multicenter randomized study did not demonstrate any benefit with the addition of cisplatin-epirubicin neoadjuvant chemotherapy for patients with locoregionally advanced nasopharyngeal carcinoma; therefore routine administration of neoadjuvant chemotherapy to this target group cannot be recommended. Although the overall incidence of recurrence was reduced with the addition of chemotherapy in the efficacy analysis, the overall survival was not affected. A more effective chemotherapy regimen, the selection of an appropriate target group, and the use of an alternative strategy for combining chemoradiotherapy should be explored in future trials.  相似文献   

20.
The importance of ornithine decarboxylase (ODC) to cell proliferation is underscored by the complex array of cell-specific mechanisms invoked to regulate its synthesis and activity. Misregulation of ODC has severe negative consequences on normal cell function, including the acquisition of tumorigenic growth properties by cells overexpressing ODC. We hypothesize that ODC gene expression is a candidate target for the anti-proliferative function of certain tumor suppressors. Here we show that the Wilms' tumor suppressor WT1 binds to multiple sites within the human ODC promoter, as determined by DNase I protection and methylation interference assays. The expression of WT1 in transfected HCT 116, NIH/3T3 and HepG2 cells represses activity of the ODC promoter controlling expression of a luciferase reporter gene. In contrast WT1 expression enhances ODC promoter activity in SV40-transfected HepG2 cells. Both the extent of modulation of ODC gene expression and the mediating WT1 binding elements are cell specific. Constructs expressing WT1 deletion mutants implicate two regions required for repressor function, as well as an intrinsic activation domain. Understanding the regulation of ODC gene expression by WT1 may provide valuable insights into the roles of both WT1 and ODC in development and tumorigenesis.  相似文献   

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