Combinatorial peptide library-based identification of peptide ligands for tumor-reactive cytolytic T lymphocytes of unknown specificity.

A novel approach for the identification of tumor antigen-derived sequences recognized by CD8(+) cytolytic T lymphocytes (CTL) consists in using synthetic combinatorial peptide libraries. Here we have screened a library composed of 3.1 x 10(11) nonapeptides arranged in a positional scanning format, in a cytotoxicity assay, to search the antigen recognized by melanoma-reactive CTL of unknown specificity. The results of this analysis enabled the identification of several optimal peptide ligands, as most of the individual nonapeptides deduced from the primary screening were efficiently recognized by the CTL. The results of the library screening were also analyzed with a mathematical approach based on a model of independent and additive contribution of individual amino acids to antigen recognition. This biometrical data analysis enabled the retrieval, in public databases, of the native antigenic peptide SSX-2(41-49), whose sequence is highly homologous to the ones deduced from the library screening, among the ones with the highest stimulatory score. These results underline the high predictive value of positional scanning synthetic combinatorial peptide library analysis and encourage its use for the identification of CTL ligands.

Management of transitional-cell carcinoma of the renal pelvis and ureter.

Transitional-cell carcinoma of the renal pelvis or ureter is a relatively rare disease. Several risk factors are smoking, occupational carcinogens, analgesic abuse or Balkan nephropathy. The grade and stage of the disease have the most significant impact on the outcome. The treatment of renal pelvis and ureter tumours is open or laparoscopic surgery varying from conservative to more extensive surgical procedures, i.e. radical nephroureterectomy including removal of the contents of Gerota's fascia with ipsilateral ureter and a cuff of bladder at its distal extent. Most available data are from retrospective studies and surgery is the mainstay of treatment. Chemotherapy and/or radiation therapy are possible adjuvant or primary treatment for selected patients; however, prospective studies are needed to confirm their use.

Thymostimulin versus placebo for palliative treatment of locally advanced or metastasised hepatocellular carcinoma: a phase III clinical trial.

BACKGROUND: Thymostimulin is a thymic peptide fraction with immune-mediated cytotoxicity against hepatocellular carcinoma (HCC) in vitro and palliative efficacy in advanced HCC in two independent phase II trials. The aim of this study was to assess the efficacy of thymostimulin in a phase III trial. METHODS: The study was designed as a prospective randomised, placebo-controlled, double-blind, multicenter clinical phase III trial. Between 10/2002 and 03/2005, 135 patients with locally advanced or metastasised HCC (Karnofsky >or=60%/Child-Pugh <or= 12) were randomised to receive thymostimulin 75 mg s.c. 5x/week or placebo stratified according to liver function. Primary endpoint was twelve-month survival, secondary endpoints overall survival (OS), time to progression (TTP), tumor response, safety and quality of life. A subgroup analysis according to liver function, KPS and tumor stage (Okuda, CLIP and BCLC) formed part of the protocol. RESULTS: Twelve-month survival was 28% [95%CI 17-41; treatment] and 32% [95%CI 19-44; control] with no significant differences in median OS (5.0 [95% CI 3.7-6.3] vs. 5.2 [95% CI 3.5-6.9] months; p = 0.87, HR = 1.04 [95% CI 0.7-1.6]) or TTP (5.3 [95%CI 2.0-8.6] vs. 2.9 [95%CI 2.6-3.1] months; p = 0.60, HR = 1.13 [95% CI 0.7-1.8]). Adjustment for liver function, Karnofsky status or tumor stage did not affect results. While quality of life was similar in both groups, fewer patients on thymostimulin suffered from accumulating ascites and renal failure. CONCLUSIONS: In our phase III trial, we found no evidence of any benefit to thymostimulin in the treatment of advanced HCC and there is therefore no justification for its use as single-agent treatment. The effect of thymostimulin on hepato-renal function requires further confirmation. TRIAL REGISTRATION: Current Controlled Trials ISRCTN64487365.

Isolated limb perfusion with tumor necrosis factor and melphalan for non-resectable soft tissue sarcomas: long-term results on efficacy and limb salvage in a selected group of patients

Background And Objectives: Isolated limb perfusion with TNF-alpha and melphalan (TM-ILP) is a limb salvage therapy for non-resectable soft tissue sarcomas (STS) of the extremities. It is indicated for patients for whom amputation or debilitating surgery is the only alternative. It can be used either as an exclusive therapy (in palliation) or as a neo-adjuvant treatment, followed by marginal resection of tumor remnants with minimal functional impairment. Methods: Between February 1992 and March 2006, 57 TM-ILPs were performed on 51 patients with 88% high grade and 84% advanced stage tumors. Results: Mean follow-up is 38.9 months (4-159, median 22 months). Twenty-one percent patients had significant early complications, with 3 major re-operations, and 23% suffered long-lasting complications. Complete response was observed in 25%, partial response in 42%, stable disease in 14% and progressive disease in 14%. Resection of the tumor remnants was possible in 65%. A complementary treatment was necessary in 31%, mostly radiation therapy. A local recurrence was observed in 35%, after a mean of 20.3 months (2-78), and distant relapse was seen in 45%, after a mean of 13.4 months (5-196). Mean Disease-free survival was 14.9 months, and overall 5-year-survival 43.5%. Amputation rate at 5 years was 24%. Conclusions: TM-ILP is a conservative treatment with a high complications rate, but it can be successful even for the most severe STS of extremities. As a consequence the limb can be spared from amputation or debilitating surgery on the long term in about 75% of patients

gp100(209-2M) peptide immunization of human lymphocyte antigen-A2+ stage I-III melanoma patients induces significant increase in antigen-specific effector and long-term memory CD8+ T cells.

Thirty-five HLA-A2(+) patients with completely resected stage I-III melanoma were vaccinated multiple times over 6 months with a modified melanoma peptide, gp100(209-2M), emulsified in Montanide adjuvant. Direct ex vivo gp100(209-2M) tetramer analysis of pre- and postvaccine peripheral blood mononuclear cells (PBMCs) demonstrated significant increases in the frequency of tetramer(+) CD8(+) T cells after immunization for 33 of 35 evaluable patients (median, 0.36%; range, 0.05-8.9%). Ex vivo IFN-gamma cytokine flow cytometry analysis of postvaccine PBMCs after brief gp100(209-2M) in vitro activation showed that for all of the patients studied tetramer(+) CD8(+) T cells produced IFN-gamma; however, some patients had significant numbers of tetramer(+) IFN-gamma(-) CD8(+)T cells suggesting functional anergy. Additionally, 8 day gp100(209-2M) in vitro stimulation (IVS) of pre- and postvaccine PBMCs resulted in significant expansion of tetramer(+) CD8(+) T cells from postvaccine cells for 34 patients, and these IVS tetramer(+) CD8(+) T cells were functionally responsive by IFN-gamma cytokine flow cytometry analysis after restimulation with either native or modified gp100 peptide. However, correlated functional and phenotype analysis of IVS-expanded postvaccine CD8(+) T cells demonstrated the proliferation of functionally anergic gp100(209-2M)- tetramer(+) CD8(+) T cells in several patients and also indicated interpatient variability of gp100(209-2M) stimulated T-cell proliferation. Flow cytometry analysis of cryopreserved postvaccine PBMCs from representative patients showed that the majority of tetramer(+) CD8+ T cells (78.1 +/- 4.2%) had either an "effector" (CD45 RA(+)/CCR7(-)) or an "effector-memory" phenotype (CD45RA(-)/CCR7(-)). Notably, analysis of PBMCs collected 12-24 months after vaccine therapy demonstrated the durable presence of gp100(209-2M)-specific memory CD8(+) T cells with high proliferation potential. Overall, this report demonstrates that after vaccination with a MHC class I-restricted melanoma peptide, resected nonmetastatic melanoma patients can mount a significant antigen-specific CD8(+) T-cell immune response with a functionally intact memory component. The data further support the combined use of tetramer binding and functional assays in correlated ex vivo and IVS settings as a standard for immunomonitoring of cancer vaccine patients.

Second primary squamous cell carcinoma arising in cutaneous flap reconstructions of two head and neck cancer patients.

Early complications of myocutaneous flap transfers following surgical eradication of head and neck tumors have been extensively described. However, knowledge concerning long-term complications of these techniques remains limited. We report the cases of two patients with a prior history of squamous cell carcinoma of the head and neck (HNSCC), who developed a second primary SCC on the cutaneous surface of their flaps, years after reconstruction. Interestingly, it seems that the well-known risk of a second primary SCC in patients with previous head and neck carcinoma also applies to foreign tissues implanted within the area at risk. Given the important expansion of these interventions, this type of complication may become more frequent in the future. Therefore, long-term follow-up of patients previously treated for HNSCC not only requires careful evaluation of the normal mucosa of the upper aero-digestive tract, but also of the cutaneous surface of the flap used for reconstruction.

Dégénérescence maculaire liée à l'âge exsudative: efficacité et limites des différents traitements [Exudative age-related macular degeneration: efficacy and limits of the different treatments].

Ocular neovascularizations are responsible for irreversible loss of vision in various diseases, including age-related macular degeneration. Treatments have changed greatly, and photodynamic therapy with verteporfin has come into common use. However, the visual prognosis remains poor. The recent approval of new antiangiogenic molecules such as ranibizumab and pegaptanib should allow for new therapeutical possibilities. The unapproved ophthalmological use of bevacizumab requires further studies. This paper updates what is known about old and new neovascularization treatments: their mechanism of action, their efficacy, and their toxicity. It reviews the principal clinical studies, and concludes with the recognized recommendations. For the first time, ophthalmologists can hope not only to stabilize loss of vision, but also to improve visual acuity. Complementary treatments can now be tested in associations, concomitantly or not, with the hope of improving visual results.

MYC and metastasis.

Aggressive primary tumors express transcriptional signatures that correlate with their metastatic propensity. A number of these signatures have been deployed in the clinic as risk stratification tools. However, the molecular basis of these clinically useful prognostic signatures has remained a largely unresolved area of controversy. We recently found that many prognostic signatures reflect the activity of the MYC oncogene, which in turn regulates tumor metastasis through specific effects on cancer cell invasion and migration. These findings offer a general framework for understanding the molecular basis of clinically prognostic transcriptional signatures and suggest potentially new avenues for studying metastasis.

A phase I pharmacokinetic study of hypoxic abdominal stop-flow perfusion with gemcitabine in patients with advanced pancreatic cancer and refractory malignant ascites

PURPOSE: As no curative treatment for advanced pancreatic and biliary cancer with malignant ascites exists, new modalities possibly improving the response to available chemotherapies must be explored. This phase I study assesses the feasibility, tolerability and pharmacokinetics of a regional treatment of gemcitabine administered in escalating doses by the stop-flow approach to patients with advanced abdominal malignancies (adenocarcinoma of the pancreas, n = 8, and cholangiocarcinoma of the liver, n = 1). EXPERIMENTAL DESIGN: Gemcitabine at 500, 750 and 1,125 mg/m(2) was administered to three patients at each dose level by loco-regional chemotherapy, using hypoxic abdominal stop-flow perfusion. This was achieved by an aorto-caval occlusion by balloon catheters connected to an extracorporeal circuit. Gemcitabine and its main metabolite 2',2'-difluorodeoxyuridine (dFdU) concentrations were measured by high performance liquid chromatography with UV detection in the extracorporeal circuit during the 20 min of stop-flow perfusion, and in peripheral plasma for 420 min. Blood gases were monitored during the stop-flow perfusion and hypoxia was considered stringent if two of the following endpoints were met: pH </= 7.2, pO(2) nadir ratio </=0.70 or pCO(2) peak ratio >/=1.35. The tolerability of this procedure was also assessed. RESULTS: Stringent hypoxia was achieved in four patients. Very high levels of gemcitabine were rapidly reached in the extracorporeal circuit during the 20 min of stop-flow perfusion, with C (max) levels in the abdominal circuit of 246 (+/-37%), 2,039 (+/-77%) and 4,780 (+/-7.3%) mug/ml for the three dose levels 500, 750 and 1,125 mg/m(2), respectively. These C (max) were between 13 (+/-51%) and 290 (+/-12%) times higher than those measured in the peripheral plasma. Similarly, the abdominal exposure to gemcitabine, calculated as AUC(t0-20), was between 5.5 (+/-43%) and 200 (+/-66%)-fold higher than the systemic exposure. Loco-regional exposure to gemcitabine was statistically higher in presence of stringent hypoxia (P < 0.01 for C (max) and AUC(t0-20), both normalised to the gemcitabine dose). Toxicities were acceptable considering the complexity of the procedure and were mostly hepatic; it was not possible to differentiate the respective contributions of systemic and regional exposures. A significant correlation (P < 0.05) was found between systemic C (max) of gemcitabine and the nadir of both leucocytes and neutrophils. CONCLUSIONS: Regional exposure to gemcitabine-the current standard drug for advanced adenocarcinoma of the pancreas-can be markedly enhanced using an optimised hypoxic stop-flow perfusion technique, with acceptable toxicities up to a dose of 1,125 mg/m(2). However, the activity of gemcitabine under hypoxic conditions is not as firmly established as that of other drugs such as mitomycin C, melphalan or tirapazamine. Further studies of this investigational modality, but with bioreductive drugs, are therefore warranted first to evaluate the tolerance in a phase I study and later on to assess whether it does improve the response to chemotherapy.

Reactivity of antiglioma monoclonal antibodies for a large panel of cultured gliomas and other neuroectoderm derived tumors.

We produced three monoclonal antibodies, BF7, GE2 and CG12, against cultured human glioma cells. Their specificity was tested by an indirect antibody-binding radioimmunoassay on a panel of glial and non-glial tumor cell lines. BF7 and GE2 react preferentially with glioma cells and, except for one colon carcinoma line, they do not bind to the control non-neuroectodermal cells; they appear to be directed against common malignant glioma associated antigens. CG12, the third monoclonal antibody, binds to the great majority of tumor cell lines of neuroectodermal origin and does not bind to any other cell lines tested.

Telomerase activation in colorectal carcinogenesis.

Telomerase activity has been detected in germ cells as well as in the developing embryo. Activity is no longer detectable in most somatic cells of the neonate, although low levels of activity persist in regenerative tissues. Telomerase has been found to be reactivated or up-regulated in the majority of cancers. The colorectal adenoma-carcinoma sequence is one of the best-characterized models of multistep tumourigenesis and is thus suitable for determining at which stage telomerase is activated. Telomerase activity was examined by telomeric repeat amplification protocol (TRAP) assay in 96 cases of colorectal tissues, including 50 carcinomas, 31 adenomas, and 15 normal colonic tissues. For each case, histological diagnosis and telomerase activity were determined on consecutive frozen sections. In order to reduce the chance of a false-negative TRAP assay due to RNA degradation, the integrity of rRNA in the tissues was verified in each case. Twenty-five carcinomas, 30 adenomas, and all of the 15 normal colorectal mucosal samples showed no or only partial rRNA degradation and only in these cases was the TRAP assay interpreted. None of the normal tissues exhibited telomerase activity. In contrast, all of the 25 cancers and 47 per cent (14/30) of the adenomas were positive. In adenomas, telomerase activation was highly significantly related to the grade of dysplasia (p< 0.0001). All adenomas which contained high-grade dysplasia revealed telomerase activity, whereas telomerase activity was detectable in only 20 per cent (4/20) of cases with exclusively low-grade dysplasia. These results indicate that telomerase activation, which may be an obligatory step in colorectal carcinogenesis, occurs in the progression from low-grade to high-grade dysplasia in adenomas. Furthermore, in the adenoma-carcinoma sequence, telomerase activation seems to occur later than K- ras mutation but earlier than p53 mutation.

Common human melanoma-associated antigen(s) detected by monoclonal antibodies.

Hybridoma cells have been derived from a fusion between mouse myeloma cells (P3-NSI/1Ag4) and spleen cells from a mouse immunized with membrane-enriched fractions from the human melanoma cell line Me-43. Of the 26 hybrids obtained, seven secreted antibodies which reacted with the melanoma cell line used for immunoassay. The specificity of the antibodies produced by the seven positive hybrids was further investigated on 16 melanoma cell lines, 15 other tumors, and 14 lymphoblastoid cell lines. The antibodies from four positive hybrids showed a broad reactivity, whereas those from three hybrids reacted exclusively with melanoma cells. The antibodies from two of these three hybrids, alpha-Mel/5 and alpha-Mel/14, seem to be directed against common melanoma antigen(s) since they reacted with all (with one exception) of the 16 melanoma cell lines tested only with five of the 16 melanoma lines. Reciprocal binding inhibition tests using [3H]leeucine-labeled antibodies showed that alpha-Mel/5 and alpha-Mel/14 antibodies were directed against different antigenic determinants.

Coexpression of the T-cell receptor constant alpha domain triggers tumor reactivity of single-chain TCR-transduced human T cells.

Transfer of tumor antigen-specific T-cell receptors (TCRs) into human T cells aims at redirecting their cytotoxicity toward tumors. Efficacy and safety may be affected by pairing of natural and introduced TCRalpha/beta chains potentially leading to autoimmunity. We hypothesized that a novel single-chain (sc)TCR framework relying on the coexpression of the TCRalpha constant alpha (Calpha) domain would prevent undesired pairing while preserving structural and functional similarity to a fully assembled double-chain (dc)TCR/CD3 complex. We confirmed this hypothesis for a murine p53-specific scTCR. Substantial effector function was observed only in the presence of a murine Calpha domain preceded by a TCRalpha signal peptide for shuttling to the cell membrane. The generalization to a human gp100-specific TCR required the murinization of both C domains. Structural and functional T-cell avidities of an accessory disulfide-linked scTCR gp100/Calpha were higher than those of a dcTCR. Antigen-dependent phosphorylation of the proximal effector zeta-chain-associated protein kinase 70 at tyrosine 319 was not impaired, reflecting its molecular integrity in signaling. In melanoma-engrafted nonobese diabetic/severe combined immunodeficient mice, adoptive transfer of scTCR gp100/Calpha transduced T cells conferred superior delay in tumor growth among primary and long-term secondary tumor challenges. We conclude that the novel scTCR constitutes a reliable means to immunotherapeutically target hematologic malignancies.