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51.
Background: On the basis of our previous experience, we designed this study to determine the activity and toxicity of outpatient treatment with autologous tumor-infiltrating lymphocytes (TIL) together with intermediate-dose recombinant interleukin-2 (rIL-2) and low-dose recombinant interferon alfa-2a (rIFN-2a), for patients with metastatic melanoma.Methods: Between April 1992 and October 1994, we processed 38 melanoma samples derived from 36 patients with metastases. Proliferative cultures of expanded lymphocytes (TIL) were infused only once into patients with metastatic melanoma. rIL-2 was administered subcutaneously for 1 month, starting on the day of TIL infusion, at an escalating dose of 6–18 × 106 IU/m2/day for the first week and at the maximum-tolerated dose for the subsequent 3 weeks and then, after a 15-day interval, for 1 week/month for 3 months. rIFN-2a was administered subcutaneously at 3 × 106 IU three times each week until progression.Results: Of 38 melanoma samples, 19 (50%) resulted in proliferative cultures and were infused. The median number of expanded lymphocytes was 18 × 109 (range, 1–43 × 109), and the median period of culture was 52 days (range, 45–60). rIL-2 was administered at doses ranging between 6 and 18 × 106 IU/m2/day. Toxicity was mild or moderate, and no life-threatening side effects were encountered. Two of 19 treated patients experienced complete responses of their metastatic sites (soft tissue), 10 had stable disease, and 7 showed progressive disease. The response rate was 11% (95% confidence interval, 2–35%).Conclusions: Outpatient treatment with TIL plus rIL-2 and rIFN-2a is feasible, although, within the context of the small sample size, the activity of the combination was no different from the reported activity of any of the components used alone.  相似文献   
52.
Viral transformation models may be useful for detecting and mapping human tumor suppressor genes. BK virus (BKV), a human papovavirus, readily transforms rodent cells but is unable to transform human cells, suggesting that oncosuppressive functions expressed in human cells control BKV oncogenic activity. We have transferred human chromosome 11 to BKV-transformed mouse cells. All of the cell clones were suppressed in the tumorigenic phenotype and anchorage-independent growth, except one clone which was nontumorigenic but maintained the ability to grow in soft agar. Cytogenetic analysis and DNA hybridization with chromosome 11-specific probes showed that all the reverted hybrids had an intact human chromosome 11, except the clone growing in semisolid medium which had lost the short arm. The results suggest that a gene located on 11p controls anchorage independence, whereas a gene on 11q controls the tumorigenicity of BKV-transformed cells. BKV T-antigen was expressed in all the hybrid clones at the same level as in the parental cell line, indicating that the putative human tumor suppressor gene(s) do not inhibit expression of the viral oncogene and must operate by another mechanism in inducing reversion of the oncogenic phenotype. Since BKV-transformed mouse cells are highly susceptible to retrovirus infection, this model can be used for searching and cloning tumor suppressor gene(s) by retrovirus-mediated "insertional mutagenesis".  相似文献   
53.
Deletion 22q11.2 is a chromosomal abnormality detected in young patients with clinical manifestations of the DiGeorge/velocardiofacial syndrome. Conotruncal heart defects are also associated with del22q11.2. An association of these cardiac malformations with neoplasias has been observed. Our series includes two cases of malignancies, a hepatoblastoma and a renal-cell carcinoma, arising in children with complex cardiac malformations. The aim of the study was to determine if the deletion at 22q11.2 was present and could be responsible for both pathological processes. Del22q11.2 was identified in both cases. Comparative genomic hybridization revealed terminal gains on chromosomes 1q and Xq and terminal loss on 1p in the hepatoblastoma, and gains in 1p, 12q, 16p, 20q, 22q, and whole chromosome 19 and loss of Xq in the renal-cell carcinoma. Our results confirm a common genetic basis for cardiac malformations, and del22q11.2 presents a risk factor for the development of pediatric tumours.  相似文献   
54.
PURPOSE: To investigate the possible existence of an antiapoptotic cross-talk between HER-2 and antiapoptotic Bcl-2 family members. EXPERIMENTAL DESIGN: Bcl-2 and Bcl-XL expression and apoptosis induction were analyzed in HER-2 gene-amplified (BT474) and nonamplified (ZR 75-1) breast cancer cell lines exposed to trastuzumab, alone or in combination with either Bcl-2/Bcl-XL bispecific antisense oligonucleotides (AS-4625) or the small-molecule Bcl-2 antagonist HA14-1. RESULTS: In addition to HER-2 and epidermal growth factor receptor, trastuzumab down-regulated Bcl-2, but not Bcl-XL, protein, and mRNA expression in BT474 cells. Interestingly, trastuzumab-induced down-regulation of HER-2 and Bcl-2 was also observed in three of five and two of three breast cancer patients undergoing trastuzumab treatment, respectively. Despite Bcl-2 down-regulation, however, trastuzumab only marginally increased the rate of apoptosis (7.3 +/- 3.5%). We therefore investigated whether a combination of AS-4625 and trastuzumab might increase proapoptotic efficiency. AS-4625 treatment of BT474 cells decreased both Bcl-2 and Bcl-XL expression, resulting in a 21 +/- 7% net apoptosis induction; the combination of AS-4625 followed by trastuzumab resulted in a significantly stronger induction of apoptosis (37 +/- 6%, P <0.01) that was not observed with the reverse treatment sequence (trastuzumab followed by AS-4625). Similar results were obtained with the Bcl-2 antagonist HA14-1; indeed, exposure of BT474 cells to HA14-1 followed by trastuzumab resulted in a striking proapoptotic synergism (combination index=0.58 +/- 0.18), as assessed by isobologram analysis. CONCLUSIONS: Altogether our findings suggest that combined targeting of HER-2 and Bcl-2 may represent a novel, rational approach to more effective breast cancer therapy.  相似文献   
55.
NAMI-A is a ruthenium complex endowed with a selective effect on lung metastases of solid metastasizing tumors. The aim of this study is to provide evidence that NAMI-A's effect is based on the selective sensitivity of the metastasis cell, as compared with other tumor cells, and to show that lungs represent a privileged site for the antimetastatic effects. The transplantation of Lewis lung carcinoma cells, harvested from the primary tumor of mice treated with 35 mg/kg/day NAMI-A for six consecutive days, a dose active on metastases, shows no change in primary tumor take and growth but a significant reduction in formation of spontaneous lung metastases. Transmission electron microscopy examination of lungs and kidney shows NAMI-A to selectively bind collagen of the lung extracellular matrix and also type IV collagen of the basement membrane of kidney glomeruli. The half lifetime of NAMI-A elimination from the lungs is longer than for liver, kidney, and primary tumor. NAMI-A bound to collagen is active on tumor cells as shown in vitro by an invasion test, using a modified Boyden chamber and Matrigel, and it inhibits the matrix metallo-proteinases MMP-2 and MMP-9 at micromolar concentrations, as shown in vitro by a zimography test. These data show NAMI-A to significantly affect tumor cells with metastatic ability. Binding to collagen allows NAMI-A to exert its selective activity on metastatic cells during dissemination and particularly in the lungs. These data also stress the wide spectrum of daily doses and treatment schedules at which NAMI-A is active against metastases.  相似文献   
56.
PURPOSE: Melanoma is a highly malignant and increasingly common tumor. Because the cure rate of metastatic melanoma by conventional treatment is very low, new therapeutic approaches are needed. We previously reported that coated cationic liposomes (CCL) targeted with a monoclonal antibody against the disialoganglioside (GD(2)) and containing c-myb antisense oligodeoxynucleotides (asODNs) resulted in a selective inhibition of the proliferation of GD(2)-positive neuroblastoma cells in vitro. EXPERIMENTAL DESIGN: Here, we tested the in vivo antitumor effects of this novel antisense liposomal formulation by targeting the c-myc oncogene on melanoma, a neuroectodermal tumor sharing with neuroblastoma the expression of GD(2). RESULTS: Our methods produced GD(2)-targeted liposomes that stably entrapped 90% of added c-myc asODNs. These liposomes showed a selective binding for GD(2)-positive melanoma cells in vitro. Melanoma cell proliferation was inhibited to a greater extent by GD(2)-targeted liposomes containing c-myc asODNs (aGD(2)-CCL-myc-as) than by nontargeted liposomes or free asODNs. The pharmacokinetic results obtained after i.v. injection of [(3)H]-myc-asODNs, free or encapsulated in nontargeted CCLs or GD(2)-targeted CCLs, showed that free c-myc-asODNs were rapidly cleared, with less than 10% of the injected dose remaining in blood at 30 min after injection. c-myc-asODNs encapsulated within either CCL or aGD(2)-CCL demonstrated a more favorable profile in blood, with about 20% of the injected dose of each preparation remaining in vivo at 24 h after injection. In an in vivo melanoma experimental metastatic model, aGD(2)-CCL-myc-as, at a total dose of only 10 mg of asODN per kilogram, significantly inhibited the development of microscopic metastases in the lung compared with animals treated with myc-asODNs, free or entrapped in nontargeted liposomes, or aGD(2)-CCL encapsulating scrambled asODNs (P < 0.01). Moreover, mice bearing established s.c. human melanoma xenografts treated with aGD(2)-CCL-myc-as exhibited significantly reduced tumor growth and increased survival (P < 0.01 versus control mice). The mechanism for the antitumor effects appears to be down-regulation of the expression of the c-myc protein and interruption of c-myc-mediated signaling: induction of p53 and inhibition of Bcl-2 proteins, leading to extensive tumor cell apoptosis. CONCLUSION: These results suggest that inhibition of c-myc proto-oncogene by GD(2)-targeted antisense therapy could provide an effective approach for the treatment of melanoma in an adjuvant setting.  相似文献   
57.
58.
PURPOSE: Bcl-2 overexpression is frequently detected in lymphoid malignancies, being associated with poor prognosis and reduced response to therapy. Here, we evaluated whether Bcl-2 overexpression affects the cytotoxic activity of proteasome inhibitors taken alone or in association with conventional anticancer drugs or tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). EXPERIMENTAL DESIGN: Jurkat cells engineered to overexpress Bcl-2 were treated with proteasome inhibitors (MG132, epoxomicin, and bortezomib), anticancer drugs (etoposide and doxorubicin), TRAIL, or combinations of these compounds. Cell death and loss of mitochondrial transmembrane potential were detected by flow cytometry. Cytosolic relocalization of cytochrome c and SMAC/Diablo, caspase cleavage, and Bcl-2 and Mcl-1 levels were determined by immunoblotting. Nuclear factor-kappaB inhibition was done by retroviral transduction with a dominant-negative mutant of IkappaBalpha. RESULTS: Bcl-2 overexpression results in significant inhibition of apoptosis in response to proteasome inhibitors, antiblastics, and TRAIL. Addition of TRAIL to proteasome inhibitors results in a synergistic cytotoxic effect in Bcl-2-overexpressing cells, whereas this result is not reproduced by the combination of proteasome inhibitors with antiblastic drugs. Importantly, proteasome inhibitors plus TRAIL induce mitochondrial dysfunction irrespective of up-regulated Bcl-2. Bcl-2 cleavage to a fragment with putative proapoptotic activity and elimination of antiapoptotic Mcl-1 may both play a role in proteasome inhibitors-TRAIL cooperation. Conversely, nuclear factor-kappaB inhibition by proteasome inhibitors is per se insufficient to explain the observed synergy. CONCLUSIONS: Combined proteasome inhibitors and TRAIL overcome the apoptotic threshold raised by Bcl-2 and may prove useful in the treatment of chemoresistant malignancies with up-regulated Bcl-2.  相似文献   
59.
Geometric cis, trans isomers, derivatives of 2-substituted-1,3-dioxanes were designed and studied as antimuscarinic agents. The synthesized compounds were evaluated as perchlorides and methiodides by functional tests with rabbit vas deferens (putative M1), guinea-pig heart (M2) and guinea-pig ileum (M3). The effect of the replacement of a trimethylammonium group with a dimethysulfonium in the two rings was also evaluated. Pharmacological results indicate that the 1,3-dioxane nucleus shows the highest stereoselective values on the studied receptors.  相似文献   
60.
Polycystic ovary syndrome (PCOS)is a gynecological endocrine disorder which is associated with systemic inflammatory status inducing red blood cells (RBC) membrane alterations related to insulin resistance and testosterone levels which could be greatly improved by myo-inositol (MYO) uptake. In this study we aim to evaluate the effect of MYO in reducing oxidative-related alterations through in vitro study on PCOS RBC. Blood samples from two groups of volunteers, control group (CG, n?=?12) and PCOS patient group (PG, n?=?12), were analyzed for band 3 tyrosine phosphorylation (Tyr-P), high molecular weight aggregate (HMWA), IgG in RBC membranes, and glutathione (GSH) in cytosol, following O/N incubation in the presence or absence of MYO. PCOS RBC underwent oxidative stress as indicated by higher band 3 Tyr-P and HMWA and increased membrane bound autologous IgG. Twenty four hours (but not shorter time) MYO incubation, significantly improved both Tyr-P level and HMWA formation and concomitant membrane IgG binding. However, no relevant modification of GSH content was detected. PCOS RBC membranes are characterized by increased oxidized level and enhanced sensitivity to oxidative injuries leading to potential premature RBC removal. MYO treatment is effective in reducing oxidative related abnormalities in PCOS patients probably restoring the inositol phospholipid pools of the membranes.  相似文献   
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