(1/1813) Sarcomatoid renal cell carcinoma: biologic behavior, prognosis, and response to combined surgical resection and immunotherapy.

PURPOSE: Sarcomatoid variants of renal cell carcinoma (RCC) are aggressive tumors that respond poorly to immunotherapy. We report the outcomes of 31 patients with sarcomatoid RCC treated with a combination of surgical resection and immunotherapy. PATIENTS AND METHODS: Patients were identified from the database of the University of California Los Angeles Kidney Cancer Program. We retrospectively reviewed the cases of 31 consecutive patients in whom sarcomatoid RCC was diagnosed between 1990 and 1997. Clinical stage, sites of metastasis, pathologic stage, and type of immunotherapy were abstracted from the medical records. The primary end point analyzed was overall survival, and a multivariate analysis was performed to distinguish any factors conferring an improved survivorship. RESULTS: Twenty-six percent of patients were male and 74% were female, and the median age was 59 years (range, 34 to 73 years). Length of follow-up ranged from 2 to 77 months (mean, 21.4 months). Twenty-eight patients (84%) had known metastases at the time of radical nephrectomy (67% had lung metastases and 40% had bone, 21% had liver, 33% had lymphatic, and 15% had brain metastases). Twenty-five patients (81%) received immunotherapy, including low-dose interleukin (IL)-2-based therapy (five patients), tumor-infiltrating lymphocyte-based therapy plus IL-2 (nine patients), high-dose IL-2-based therapy (nine patients), dendritic cell vaccine-based therapy (one patient), and interferon alpha-based therapy alone (one patient). Two patients (6%) achieved complete responses (median duration, 46+ months) and five patients (15%) achieved partial responses (median duration, 36 months). One- and 2-year overall survival rates were 48% and 37%, respectively. Using a multivariate analysis, age, sex, and percentage of sarcomatoid tumor (< or >50%) did not significantly correlate with survival. Improved survival was found in patients receiving high-dose IL-2 therapy compared with patients treated with surgery alone or any other form of immunotherapy (P = .025). Adjusting for age, sex, and percentage of sarcomatoid tumor, the relative risk of death was 10.4 times higher in patients not receiving high-dose IL-2 therapy. Final pathologic T stage did not correlate significantly with outcome, but node-positive patients had a higher death rate per year of follow-up than did the rest of the population (1.26 v 0.76, Cox regression analysis). CONCLUSION: Surgical resection and high-dose IL-2-based immunotherapy may play a role in the treatment of sarcomatoid RCCs in select patients.  (+info)

(2/1813) Feasibility of immunotherapy of relapsed leukemia with ex vivo-generated cytotoxic T lymphocytes specific for hematopoietic system-restricted minor histocompatibility antigens.

Allogeneic bone marrow transplantation (BMT) is a common treatment of hematologic malignancies. Recurrence of the underlying malignancy is a major cause of treatment failure. Donor-derived cytotoxic T lymphocytes (CTLs) specific for patients' minor histocompatibility antigens (mHags) play an important role in both graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) reactivities. mHags HA-1 and HA-2 induce HLA-A*0201-restricted CTLs in vivo and are exclusively expressed on hematopoietic cells, including leukemic cells and leukemic precursors, but not on fibroblasts, keratinocytes, or liver cells. The chemical nature of the mHags HA-1 and HA-2 is known. We investigated the feasibility of ex vivo generation of mHag HA-1- and HA-2-specific CTLs from unprimed mHag HA-1- and/or HA-2-negative healthy blood donors. HA-1 and HA-2 synthetic peptide-pulsed dendritic cells (DCs) were used as antigen-presenting cells (APC) to stimulate autologous unprimed CD8(+) T cells. The ex vivo-generated HA-1- and HA-2-specific CTLs efficiently lyse leukemic cells derived from acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL) patients. No lytic reactivity was detected against nonhematopoietic cells. Sufficient numbers of the CTLs can be obtained for the adoptive immunotherapy purposes. In conclusion, we present a feasible, novel therapy for the treatment for relapsed leukemia after BMT with a low risk of GVHD.  (+info)

(3/1813) Management of human cytomegalovirus infection and disease after allogeneic bone marrow transplantation.

BACKGROUND AND OBJECTIVE: Human cytomegalovirus (HCMV) infection and disease remain a major cause of morbidity and mortality after bone marrow transplantation. HCMV disease, especially pneumonitis, may be treated with ganciclovir and immunoglobulin but even so the outcome is poor with mortality rates of 30-70%. It is therefore imperative to treat HCMV infection before it develops into disease. The aim of this article is to describe the main strategies used to prevent HCMV infection and to improve the survival after CMV disease in bone marrow transplant recipients. INFORMATION SOURCES: In the present review, we examined personal papers in this field and articles published in journals covered by the Science Citation Index and Medline. STATE OF THE ART: Major advances have been made in preventing HCMV infection and disease through two different approaches, both of which reduce HCMV induced morbidity and mortality: In pre-emptive therapy, patients are given ganciclovir when HCMV infection is first identified and this is continued 3-4 months after transplantation; in prophylactic therapy ganciclovir is given to all patients at risk of HCMV disease from engraftment up to 3-4 months post transplantation. Each strategy has advantages and disadvantages and there is no evidence for the superiority of one over the other since the overall survival is the same and the incidence of death from HCMV disease is similar. PERSPECTIVES: The use of more sensitive tests such as HCMV PCR or antigenemia may improve the outcome but probably will not eradicate all HCMV disease. Future possible strategies could include adoptive transfer of CD8+ HCMV-specific cytotoxic T lymphocytes clones derived from the donor marrow or boosting donor or patient immunity using subunit anti-HCMV vaccines such as gB or pp65.  (+info)

(4/1813) Successful adoptive immunotherapy of murine poorly immunogenic tumor with specific effector cells generated from gene-modified tumor-primed lymph node cells.

We previously reported that cytokine gene transfer into weakly immunogenic tumor cells could enhance the generation of precursor cells of tumor-reactive T cells and subsequently augment antitumor efficacy of adoptive immunotherapy. We investigated whether such potent antitumor effector T cells could be generated from mice bearing poorly immunogenic tumors. In contrast to similarly modified weakly immunogenic tumors, MCA102 cells, which are chemically induced poorly immunogenic fibrosarcoma cells transfected with cDNA for IL-2, IL-4, IL-6, IFN-gamma, failed to augment the host immune reaction. Because priming of antitumor effector T cells in vivo requires two important signals provided by tumor-associated Ags and costimulatory molecules, these tumor cells were cotransfected with a B7-1 cDNA. Transfection of both IFN-gamma and B7-1 (MCA102/B7-1/IFN-gamma) resulted in regression of s.c. tumors, while tumor transfected with other combinations of cytokine and B7-1 showed progressive growth. Cotransfection of IFN-gamma and B7-1 into other poorly immunogenic tumor B16 and LLC cells also resulted in the regression of s.c. tumors. Cells derived from lymph nodes draining MCA102/B7-1/IFN-gamma tumors showed potent antitumor efficacy, eradicating established pulmonary metastases, but this effect was not seen with parental tumors. This mechanism of enhanced antitumor efficacy was further investigated, and T cells with down-regulated L-selectin expression, which constituted all the in vivo antitumor reactivity, were significantly increased in lymph nodes draining MCA102/B7-1/IFN-gamma tumors. These T cells developed into potent antitumor effector cells after in vitro activation with anti-CD3/IL-2. The strategy presented here may provide a basis for developing potent immunotherapy for human cancers.  (+info)

(5/1813) Delivery of methoxymorpholinyl doxorubicin by interleukin 2-activated NK cells: effect in mice bearing hepatic metastases.

The possibility of using interleukin 2 (IL-2)-activated natural killer cells (A-NK) to carry methoxymorpholinyl doxorubicin (MMDX; PNU 152243) to liver-infiltrating tumours was explored in mice bearing 2-day established M5076 reticulum cell sarcoma hepatic metastases. In vitro, MMDX was 5.5-fold more potent than doxorubicin against M5076 tumour cells. MMDX uptake by A-NK cells correlated linearly with drug concentration in the incubation medium [correlation coefficient (r) = 0.999]; furthermore, as MMDX incorporation was readily reproducible in different experiments, the amount of drug delivered by A-NK cells could be modulated. In vivo experiments showed that intravenous (i.v.) injection of MMDX-loaded A-NK cells exerted a greater therapeutic effect than equivalent or even higher doses of free drug. The increase in lifespan (ILS) following A-NK cell delivery of 53 microg kg(-1) MMDX, a dosage that is ineffective when administered in free form, was similar to that observed in response to 92 microg kg(-1) free drug, a dosage close to the 10% lethal dose (ILS 42% vs. 38% respectively). These results correlated with pharmacokinetic studies showing that MMDX encapsulation in A-NK cells strongly modifies its organ distribution and targets it to tissues in which IL-2 activated lymphocytes are preferentially entrapped after i.v. injection.  (+info)

(6/1813) 4-1BBL cooperates with B7-1 and B7-2 in converting a B cell lymphoma cell line into a long-lasting antitumor vaccine.

A20 is a B cell lymphoma that constitutively expresses the costimulatory molecule B7-2 yet grows readily as a tumor in syngeneic BALB/c mice. We have compared the tumorigenicity of A20 variants expressing either B7-1 (A20/B7-1) or B7-2 (A20/B7-2) with an A20 variant expressing B7-1 and B7-2 with 4-1BBL (A20/4-1BBL), a costimulatory member of the TNF family. Mice injected with tumors expressing the vector backbone (A20/CMV) or B7-1 developed tumors within 25 days of s.c. injection. In contrast, mice injected with A20/4-1BBL were tumor free for the 150-day follow-up period, while 25% of mice injected with A20/B7-2 developed tumors. Tumorigenicity experiments using nude mice indicated the requirement for T cells for variant rejection. Almost all mice that resisted the initial tumor challenge were resistant to further challenge with the parental tumor. Splenocytes from these mice showed high CTL lytic activity against the parental tumor, A20, as well as the syngeneic BALB/c lymphoma K46J, but showed background levels of lytic activity against the congenic SCID thymoma line ST-D2 or the allogeneic EL4 thymoma. In vitro blocking experiments with anti-B7-1 plus anti-B7-2 and/or soluble 4-1BB receptor showed B7-1, B7-2, and 4-1BBL all contributed to the CTL activity. Thus, the data show that neither B7-1 or B7-2 alone can confer full immunogenicity to the A20 lymphoma but that the addition of 4-1BBL results in a tumor that is highly immunogenic and can confer long-lasting protection against challenge with parental tumor in vivo.  (+info)

(7/1813) Emergence of regulatory CD4+ T cell response to repetitive stimulation with antigen-presenting cells in vitro: implications in designing antigen-presenting cell-based tumor vaccines.

Because APCs play a crucial role in the generation of T cell-mediated immune responses, numerous clinical trials with APC-based vaccines have been initiated in different types of human cancers. Encouraging results have emerged from some of these initial studies. Thus far, APC-based vaccinations usually include multiple rounds of immunization. With this approach, although we and others have detected induction of Ag-specific CTL responses in vaccinated patients after stimulation with the same APC-based immunogen, in vitro we also find that repetitive in vitro stimulation with Ag-loaded APC can, at times, lead to the emergence of noncytolytic CD4+ T cells exhibiting the characteristic phenotype of Th2 cells. These noncytolytic CD4+ T cells synthesize large quantities of type 2 cytokines such as IL-4 and IL-10 on stimulation with the autologous APC or tumor cells in an MHC class II-restricted manner. Further, these CD4+ T cells and a cell-free supernatant factor block the activation of fresh T lymphocytes. The supernatant factor also exhibits a marked inhibitory effect on the expression of the costimulatory molecules, CD80 and CD86, by APC. The inhibitory effect of the supernatant factor can be abrogated by neutralizing IL-10 in the supernatant. These observations therefore have implications in the APC-based tumor vaccine protocol design.  (+info)

(8/1813) An antigen-targeted approach to adoptive transfer therapy of cancer.

Previous attempts to treat human malignancies by adoptive transfer of tumor-specific CTLs have been limited by the difficulty of isolating T cells of defined antigen specificity. The recent development of MHC class I/antigenic peptide tetrameric complexes that allow direct identification of antigen-specific T cells has opened new possibilities for the isolation and in vitro expansion of tumor-specific T cells. In the present study, we have derived polyclonal monospecific cell lines from circulating Melan-A-specific CTL precursors of HLA-A*0201+ melanoma patients by combining stimulation with recently identified peptide analogues of the immunodominant epitope from the melanoma-associated antigen Melan-A with staining with fluorescent HLA-A*0201/Melan-A peptide tetramers. In vitro expansion of antigen-specific CD8+ T cells was monitored by flow cytometry with the fluorescent tetramers and anti-CD8 monoclonal antibody. This analysis revealed that Melan-A 26-35 peptide analogues were much more efficient than the parental peptides in stimulating a rapid in vitro expansion of antigen-specific CD8+ T cells. These cells were then isolated by tetramer-guided cell sorting and subsequently expanded in vitro by mitogen stimulation. The resulting polyclonal but monospecific CTLs fully cross-recognized the parental peptides and were able to efficiently lyse Melan-A-expressing tumor cells. Altogether, these results pave the way to a molecularly defined approach to antigen-specific adoptive transfer therapy of cancer.  (+info)