Merkel cell polyomavirus and extrapulmonary small cell carcinoma

The Merkel cell polyomavirus (MCV) is involved in the development of up to 100% of Merkel cell cancer (MCC) cases. Early studies have reported that the virus was infrequently detected in other small cell or neuroendocrine lung carcinomas, which share histological features with MCC. The present study investigated the presence of MCV in cases of extrapulmonary small cell carcinoma (ESCC), which also shares histological features with MCC. A total of 25 cases of ESCC that were diagnosed between 2004 and 2009 were identified at The Dartmouth Hitchcock Medical Center. Archived tissue was available for testing in 16 of these cases. A total of 11 tissue specimens of MCC were used as positive controls. DNA that was extracted from the archived tissue was subjected to five separate quantitative (q)PCR assays for the detection of four MCV genomic targets. MCV DNA was detected in 3/16 (19%) of the ESCCs and in all 11 MCCs. In the three MCV-positive ESCCs, the viral target was only detected by either one or two of the PCR assays. In 8/11 MCV-positive MCCs, the DNA tested positive by either three or all four assays and the remaining three MCCs tested positive by either one or two assays. The β-globin endogenous control was detected in all the samples that were tested. Although MCC and ESCC share numerous histological features, MCV is detected at a lower frequency in ESCC. The possible role for MCV in the etiology of ESCC remains uncertain and may account for the rare cases of ESCC with no other identifiable etiology. The failure of other assays to detect MCV may be due to sequence variability in the MCV genome.

Vaccine-based immunotherapy for glioblastoma

Glioblastoma remains the most lethal human brain tumor, despite the advent of multimodal treatment approaches. Because immune tolerance plays an important role in tumor progression, adding immunotherapy has become an attractive and innovative treatment approach for these aggressive tumors. Several early-phase clinical trials have demonstrated that vaccine-based immunotherapies, including dendritic cell therapy, peptide-based vaccines and vaccines containing autologous tumor lysates, are feasible and well tolerated. These trials have revealed promising trends in overall survival and progression-free survival for patients with glioblastoma, and have paved the way for ongoing randomized controlled trials.

Imatinib for melanomas harboring mutationally activated or amplified KIT arising on mucosal, acral, and chronically sun-damaged skin

PURPOSE

Amplifications and mutations in the KIT proto-oncogene in subsets of melanomas provide therapeutic opportunities.

PATIENTS AND METHODS

We conducted a multicenter phase II trial of imatinib in metastatic mucosal, acral, or chronically sun-damaged (CSD) melanoma with KIT amplifications and/or mutations. Patients received imatinib 400 mg once per day or 400 mg twice per day if there was no initial response. Dose reductions were permitted for treatment-related toxicities. Additional oncogene mutation screening was performed by mass spectroscopy.

RESULTS

Twenty-five patients were enrolled (24 evaluable). Eight patients (33%) had tumors with KIT mutations, 11 (46%) with KIT amplifications, and five (21%) with both. Median follow-up was 10.6 months (range, 3.7 to 27.1 months). Best overall response rate (BORR) was 29% (21% excluding nonconfirmed responses) with a two-stage 95% CI of 13% to 51%. BORR was significantly greater than the hypothesized null of 5% and statistically significantly different by mutation status (7 of 13 or 54% KIT mutated v 0% KIT amplified only). There were no statistical differences in rates of progression or survival by mutation status or by melanoma site. The overall disease control rate was 50% but varied significantly by KIT mutation status (77% mutated v 18% amplified). Four patients harbored pretreatment NRAS mutations, and one patient acquired increased KIT amplification after treatment.

CONCLUSION

Melanomas that arise on mucosal, acral, or CSD skin should be assessed for KIT mutations. Imatinib can be effective when tumors harbor KIT mutations, but not if KIT is amplified only. NRAS mutations and KIT copy number gain may be mechanisms of therapeutic resistance to imatinib.

Pdl-1/pdl-3 (programmed death ligand-1/3) tissue expression and response to treatment with IL2 and antiangiogenic therapies

4521

Background: Expression of PDL1 by RCC has been associated with aggressive histology and poor survival. Tissue obtained from the patients enrolled in the IL-2 Select Trial, a prospective, single arm, multicenter CWG study, was analyzed by IHC to determine if PDL1or PDL3 expression predicted for response to initial or subsequent therapy. Methods: Paraffin embedded tumor tissue was stained for PDL1 and PDL3 expression, and results were correlated with RECIST defined response to IL2 treatment. Tumor tissue was considered positive for PDL1 if >5% of the tumor membranes stained for the marker. A cutoff of 10% was used for PDL3. Duration of subsequent VEGFR/mTOR inhibitor therapy was also correlated with tissue PDL1/3 expression. Results: 120 eligible pts were enrolled; 115 had clear cell histology. The overall response rate (ORR) to IL2 was 25% (30/120) with a median OS of 40.6 months. 113 tumors were stained. 18 (16%) were PDL1+. ORR was 19% and 50% in the patients PDL1- and PDL1+ tumors, respectively (p=0.012). 85 (75%) tumors were PDL3+. ORR was 10.7% and 29.4% in the PDL3- and PDL3+ tumors, respectively (p=0.075). In the 17 patients who were positive for both PDL1 and PDL3, ORR was 52.9%. In the 27 pts who were negative for both PDL1 and PDL3, ORR was 11.1%. 69 patients received at least 1 dose of a VEGFR TKI as next therapy following IL2 treatment. 66 tumors were stained. Pts who were PDL1+/PDL3+ had a shorter duration on VEGFR TKI therapy compared to pts who were PDL1-/PDL3- (see Table). Conclusions: This small, retrospective analysis suggests that PDL1 and PDL3 tissue expression may predict for better response to IL2. PDL1 expression has been suggested as a possible predictor of response to anti-PD1 therapy. The current data suggests that its expression may predict for benefit to other immune therapies. PDL3 (+/- PDL1) expression appears to correlate to less benefit from subsequent VEGFR TKI therapy. Funded by NCI SPORE Grant # 5 P50 CA101942-08. [Table: see text]

A phase I study of nivolumab (anti-PD-1; BMS-936558; ONO-4538) in combination with sunitinib, pazopanib, or ipilimumab in patients (pts) with metastatic renal cell carcinoma (mRCC)

TPS4593

Background: Vascular endothelial growth factor receptor-tyrosine kinase inhibitors are established therapies for mRCC. However, sunitinib and pazopanib rarely elicit durable responses. Programmed death-1 receptor (PD-1) is an immune checkpoint modulator that suppresses T-cell activation by interacting with its ligands (PD-L1/2) on antigen presenting cells and some tumor cells. Nivolumab, a PD-1 receptor blocking antibody, has shown durable responses in previously treated pts with mRCC in Phase 1 and 2 trials. Ipilimumab is an immune checkpoint inhibitor (anti-CTLA-4 antibody) already approved for the treatment of advanced melanoma. We describe an ongoing Phase 1 dose-escalation and expansion study evaluating combination of nivolumab with sunitinib, pazopanib or ipilimumab in pts with mRCC. Methods: Patients with histologically confirmed mRCC are treated on 4 parallel arms: nivolumab 2.0 or 5.0 mg/kg + sunitinib standard dosing (Arm S), nivolumab 2.0 or 5.0 mg/kg + pazopanib standard dosing (Arm P), nivolumab 3 mg/kg + ipilimumab 1 mg/kg as induction (Arm I-1), and nivolumab 1 mg/kg + ipilimumab 3 mg/kg as induction (Arm I-3) with nivolumab 3 mg/kg maintenance for both arms. Arms S and P are being conducted in 2 phases: nivolumab dose-escalation phase for previously treated pts (≤18 pts/arm) and then dose-expansion phase for treatment-naïve pts (20 pts/arm) if the maximum tolerated dose is ≥5 mg/kg. Arms I-1 and I-3 are fixed-dose cohorts (20 pts/arm) including both treatment-naïve and previously treated pts. Most of the study population consists of pts with clear-cell histology; non-clear cell mRCC pts are allowed in the dose-escalation cohorts of Arms S and P. The primary objectives are to assess safety and tolerability, and to determine the recommended Phase 2 dose in pts with mRCC. The secondary objective is to assess preliminary antitumor activity (objective response rate and response duration per RECIST 1.1). Exploratory objectives are to evaluate overall survival, pharmacodynamics, and predictive biomarkers for the combinations, and pharmacokinetics and immunogenicity of nivolumab. Clinical trial information: NCT01472081.

Recent skin self-examination and doctor visits in relation to melanoma risk and tumour depth

BACKGROUND

Little is known about the potential benefit of skin self-examination for melanoma prevention and early detection.

OBJECTIVES

To determine whether skin self-examination is associated with reduced melanoma risk, self-detection of tumours, and reduced risk of deeper melanomas.

METHODS

We used data from a population-based case-control study (423 cases, 678 controls) to assess recent skin self-examination in relation to self-detection, melanoma risk and tumour depth ( ≤1 mm; > 1 mm). Logistic regression was used to estimate odds ratios (ORs) and confidence intervals (CIs) for associations of interest.

RESULTS

Skin self-examination conducted 1-11 times during a recent year was associated with a possible decrease in melanoma risk (OR 0·74; 95% CI 0·54-1·02). Melanoma risk was decreased for those who conducted skin self-examination and saw a doctor (OR 0·52; 95% CI 0·30-0·90). Among cases, those who examined their skin were twice as likely to self-detect the melanoma (OR 2·23; 95% CI 1·47-3·38), but self-detection was not associated with shallower tumours. Tumour depth was reduced for those who conducted skin self-examination 1-11 times during a recent year (OR 0·39; 95% CI 0·18-0·81), but was not influenced by seeing a doctor, or by conducting skin self-examination and seeing a doctor.

CONCLUSIONS

Risk of a deeper tumour and possibly risk of melanoma were reduced by skin self-examination 1-11 times annually. Melanoma risk was markedly reduced by skin self-examination coupled with a doctor visit. We cannot, however, exclude the possibility that our findings reflect bias or confounding. Additional studies are needed to elucidate the potential benefits of skin self-examination for melanoma prevention and early detection.

Adoptive cellular therapy using cells enriched for NKG2D+CD3+CD8+T cells after autologous transplantation for myeloma

The number of circulating lymphocytes on day 15 after transplantation correlates with improved survival in patients with myeloma, but the lymphocyte subset responsible is unknown. NKG2D is a natural killer (NK) cell activating receptor that mediates non-MHC restricted and TCR-independent cell lysis. Our preliminary results indicate that CD3(+)CD8(+) T cells expressing NKG2D may be a critical lymphocyte population. A phase II trial examined the feasibility of infusing ex vivo-expanded cells enriched for NKG2D(+)CD3(+)CD8(+) T cells at weeks 1, 2, 4, and 8 after an autologous transplantation. In addition, low-dose IL-2 (6 × 10(5) IU/m(2)/day) was administered for 4 weeks, beginning on the day of transplantation. Twenty-three patients were accrued and 19 patients are evaluable. There were no treatment-related deaths. All patients completed their course of IL-2 and demonstrated normal engraftment. When compared with patients with myeloma who underwent transplantation not receiving posttransplantation immune therapy, the treated patients demonstrated an increase in the number of circulating NKG2D(+)CD3(+)CD8(+) T cells/μL (P < .004), CD3(+)CD8(+) T cells/μL (P < .04), CD3(+)CD8(+)CD56(+) T cells/μL (P < .004), and NKG2D(+)CD3(-)CD56(+) T cells/μL (P < .003). Myeloma cell-directed cytotoxicity by the circulating mononuclear cells increased after transplantation (P < .002). When compared to posttransplantation IL-2 therapy alone in this patient population, the addition of cells enriched for NKG2D(+)CD3(+)CD8(+) T cells increased tumor-specific immunity, as demonstrated by enhanced lysis of autologous myeloma cells (P = .02). We postulate that this regimen that increased the number and function of the NKG2D(+)CD3(+)CD8(+) T cells after transplantation may improve clinical outcomes by eliminating residual malignant cells in vivo.

Regulatory T-cells and associated pathways in metastatic renal cell carcinoma (mRCC) patients undergoing DC-vaccination and cytokine-therapy

Purpose

To evaluate CD4⁺CD25⁺FOXP3⁺ T regulatory cells (T_REG) and associated immune-regulatory pathways in peripheral blood lymphocytes (PBL) of metastatic renal cell carcinoma (mRCC) patients and healthy volunteers. We subsequently investigated the effects of immunotherapy on circulating T_REG combining an extensive phenotype examination, DNA methylation analysis and global transcriptome analysis.

Design

Eighteen patients with mRCC and twelve volunteers (controls) were available for analysis. T_REG phenotype was examined using flow cytometry (FCM). T_REG were also quantified by analyzing the epigenetic status of the FOXP3 locus using methylation specific PCR. As a third approach, RNA of the PBL was hybridized to Affymetrix GeneChip Human Gene 1.0 ST Arrays and the gene signatures were explored using pathway analysis.

Results

We observed higher numbers of T_REG in pre-treatment PBL of mRCC patients compared to controls. A significant increase in T_REG was detected in all mRCC patients after the two cycles of immunotherapy. The expansion of T_REG was significantly higher in non-responders than in responding patients. Methylation specific PCR confirmed the FCM data and circumvented the variability and subjectivity of the FCM method. Gene Set Enrichment Analysis (GSEA) of the microarray data showed significant enrichment of FOXP3 target genes, CTLA-4 and TGF-ß associated pathways in the patient cohort.

Conclusion

Immune monitoring of the peripheral blood and tumor tissue is important for a wide range of diseases and treatment strategies. Adoption of methodology for quantifying T_REG with the least variability and subjectivity will enhance the ability to compare and interpret findings across studies.

A phase I study of BMS-936558 plus sunitinib or pazopanib in patients with metastatic renal cell carcinoma

TPS2614

Background: Standard treatments for metastatic renal cell carcinoma (mRCC) block the vascular endothelial growth factor pathway (eg, sunitinib, pazopanib) or mammalian target of rapamycin pathway (e.g., temsirolimus, everolimus). However, most patients (pts) develop resistance and complete responses are rare. Upregulation of programmed death-1 (PD-1) in tumor infiltrating lymphoctyes, and its ligand PD-L1 in tumors, is associated with more aggressive disease and poor prognosis. Blocking the PD-1/PD-L1 interaction is a novel immunotherapeutic approach for mRCC. In preliminary results of a phase I trial, the anti-PD-1 monoclonal antibody BMS-936558 had antitumor activity in pts with advanced tumors, including objective responses (ORs) in 6 of 18 pts with mRCC. Here we describe a phase I study planned to evaluate the safety, tolerability, and maximum tolerated dose (MTD) of BMS-936558, when combined with sunitinib or pazopanib in pts with mRCC. Methods: This open-label study will have two parallel treatment arms (BMS-936558 plus sunitinib and BMS-936558 plus pazopanib) conducted in two parts (dose escalation and dose expansion). Pts must have received ≥1 prior systemic therapy to be eligible for dose escalation. Only treatment-naïve pts will be eligible for dose expansion. Up to 36 pts (18 per arm) will be treated in the dose-escalation phase. After determining the MTD of BMS-936558, treatment-naïve pts will be enrolled to expansion cohorts allowing 24 pts to be treated at the MTD of each arm. Each treatment cycle will be 6 weeks, with BMS-936558 dosed on Days 1 and 22 and sunitinib or pazopanib given according to product label. Adverse events will be graded according to NCI CTCAE v4.0. Disease will be assessed every 6 weeks for the first four assessments and then every 12 weeks until disease progression. Pts will be treated until unacceptable toxicity, disease progression, or withdrawal of consent. The safety profile in pts treated at the MTD will be used to determine the recommended phase II study dose of BMS-936558 in each combination arm. Secondary objectives will include OR rate and duration of response based on RECIST 1.1. Exploratory analyses will investigate predictive biomarkers of BMS-936558.

Ipilimumab in patients with melanoma and brain metastases: an open-label, phase 2 trial

BACKGROUND

Brain metastases commonly develop in patients with melanoma and are a frequent cause of death of patients with this disease. Ipilimumab improves survival in patients with advanced melanoma. We aimed to investigate the safety and activity of this drug specifically in patients with brain metastases.

METHODS

Between July 31, 2008, and June 3, 2009, we enrolled patients with melanoma and brain metastases from ten US centres who were older than 16 years into two parallel cohorts. Patients in cohort A were neurologically asymptomatic and were not receiving corticosteroid treatment at study entry; those in cohort B were symptomatic and on a stable dose of corticosteroids. Patients were to receive four doses of 10 mg/kg intravenous ipilimumab, one every 3 weeks. Individuals who were clinically stable at week 24 were eligible to receive 10 mg/kg intravenous ipilimumab every 12 weeks. The primary endpoint was the proportion of patients with disease control, defined as complete response, partial response, or stable disease after 12 weeks, assessed with modified WHO criteria. Analyses of safety and efficacy included all treated patients. This trial is registered with ClinicalTrials.gov, number NCT00623766.

FINDINGS

We enrolled 72 patients: 51 into cohort A and 21 into cohort B. After 12 weeks, nine patients in cohort A exhibited disease control (18%, 95% CI 8-31), as did one patient in cohort B (5%, 0·1-24). When the brain alone was assessed, 12 patients in cohort A (24%, 13-38) and two in cohort B (10%, 1-30) achieved disease control. We noted disease control outside of the brain in 14 patients (27%, 16-42) in cohort A and in one individual (5%, 0·1-24) in cohort B. The most common grade 3 adverse events in cohort A were diarrhoea (six patients [12%]) and fatigue (six [12%]); in cohort B, they were dehydration (two individuals [10%]), hyperglycaemia (two [10%]), and increased concentrations of serum aspartate aminotransferase (two [10%]). One patient in each cohort had grade 4 confusion. The most common grade 3 immune-related adverse events were diarrhoea (six patients [12%]) and rash (one [2%]) in cohort A, and rash (one individual [5%]) and increased concentrations of serum aspartate aminotransferase (two [10%]) in cohort B. One patient in cohort A died of drug-related complications of immune-related colitis.

INTERPRETATION

Ipilimumab has activity in some patients with advanced melanoma and brain metastases, particularly when metastases are small and asymptomatic. The drug has no unexpected toxic effects in this population.

FUNDING

Bristol-Myers Squibb.

Immunotherapy for the treatment of glioblastoma

Glioblastoma, the most aggressive primary brain tumor, thrives in a microenvironment of relative immunosuppression within the relatively immune-privileged central nervous system. Despite treatments with surgery, radiation therapy, and chemotherapy, prognosis remains poor. The recent success of immunotherapy in the treatment of other cancers has renewed interest in vaccine therapy for the treatment of gliomas. In this article, we outline various immunotherapeutic strategies, review recent clinical trials data, and discuss the future of vaccine therapy for glioblastoma.

Phase 2 trial of linifanib (ABT-869) in patients with advanced renal cell cancer after sunitinib failure

PURPOSE

This study assessed the efficacy and safety of linifanib in patients with advanced renal cell carcinoma (RCC) who were previously treated with sunitinib.

MATERIALS AND METHODS

This open-label, multicentre, phase 2 trial of oral linifanib 0.25 mg/kg/day enrolled patients who had prior nephrectomy and adequate organ function. The primary end-point was objective response rate (ORR) per response evaluation criteria in solid tumors (RECIST) by central imaging. Secondary end-points were progression-free survival (PFS), overall survival (OS) and time to progression (TTP). Safety was also assessed.

RESULTS

Fifty-three patients, median age 61 years (range 40-80) were enrolled (August 2007 to October 2008) across 12 North-American centres. Median number of prior therapies was 2 (range 1-4); 43 patients (81%) had clear-cell histology. ORR was 13.2%, median PFS was 5.4 months (95% Confidence Interval (CI): 3.6, 6.0) and TTP was the same; median OS was 14.5 months (95% CI: 10.8, 24.1). The most common treatment-related adverse events (AEs) were diarrhoea (74%), fatigue (74%) and hypertension (66%), and the most common treatment-related Grade 3/4 AE was hypertension (40%).

CONCLUSIONS

Linifanib demonstrated clinically meaningful activity in patients with advanced RCC after sunitinib failure. At 0.25 mg/kg/day, significant dose modifications were required. An alternative, fixed-dosing strategy is being evaluated in other trials.

A phase 1 study of a vaccine targeting preferentially expressed antigen in melanoma and prostate-specific membrane antigen in patients with advanced solid tumors

Preferentially expressed antigen in melanoma (PRAME) and prostate-specific membrane antigen (PSMA) are tumor-associated antigens implicated in cellular differentiation, genetic stability, and angiogenesis. MKC1106-PP is an immunotherapeutic regimen cotargeting PRAME and PSMA, comprised of a recombinant plasmid (pPRA-PSM encoding fragments derived from both antigens) and 2 peptides (E-PRA and E-PSM derived from PRAME and PSMA, respectively). This multicenter study evaluated MKC1106-PP with a fixed plasmid dose and 2 different peptide doses, administered by intralymph node injection in a prime-boost sequence in human leukocyte antigen-A*0201 and tumor-antigen-positive patients with progressing metastatic solid tumors who had failed standard therapy. Immune monitoring was done by tetramer and enzymatic-linked immune spot analysis. The treatment was well tolerated, with no significant differences in safety, immune response, and clinical outcome relative to peptide doses. Fifteen of 24 evaluable patients showed an immune response, as defined by the expansion of PRAME-specific or PSMA-specific T cells in the blood. There were no partial or complete responses by the Response Evaluation Criteria in Solid Tumors. Seven patients showed stable disease (SD) for 6 months or longer, or prostate specific antigen decline: 4 of 10 with prostate carcinoma, 2 of 2 with renal clear cell carcinoma, and 1 of 10 with metastatic melanoma. In addition, there was an association between the induction and persistence of antigen-specific T cells in blood above baseline levels and disease control, defined as SD for 6 months or longer. These results support further development of MKC1106-PP in specific clinical indications.

Therapeutic vaccines in renal cell carcinoma

Metastatic renal cell carcinoma (mRCC) is a lethal disease. The advent of tyrosine kinase inhibitors (TKIs) has changed the disease process, yet the majority of patients will develop treatment-resistant disease. IL-2 based immunotherapy in mRCC is the only US FDA-approved treatment with curative results. Immunotherapeutic vaccine approaches to mRCC have been under investigation for several decades with mixed results. The recent FDA-approval of the first cellular immunotherapy in prostate cancer (Provenge(®)) has reinvigorated the search for similar vaccines approaches in mRCC. This review introduces the concepts and different features required for a successful anticancer vaccine approach.

Novel mobilization strategies to enhance autologous immune effector cells in multiple myeloma

The immune system plays a critical role determining the outcomes in transplanted multiple myeloma patients, since enhanced lymphocyte recovery results in improved survival. Since mobilization regimens influence the cellular subsets collected and infused for transplant, these regimens may determine immune recovery following transplant. We hypothesized that a mobilized stem cell product harboring an increased number of lymphocytes would enhance immune recovery following autologous stem cell infusion, increase lymphocyte recovery, and improve clinical outcomes. We designed a phase I immune mobilization trial using IL-2 and growth factors to increase the number of lymphocytes within the stem cell product. This regimen efficiently mobilized CD34+ progenitor cells (median: 3.6 x 10(6) cells/kg; range 1.9-6.6 x 10(6) cells/kg) and improved the immune properties of the mobilized stem cells, including an increase in CD8+ T cells expressing an NK activating receptor called NKG2D (P less than 0.004), cells that are extremely potent at killing myeloma cells using non-MHC-I restricted and TCR-independent mechanisms. Novel mobilization techniques can improve the mobilized graft and may improve clinical outcomes in myeloma patients.

Autoimmune melanocyte destruction is required for robust CD8+ memory T cell responses to mouse melanoma

A link between autoimmunity and improved antitumor immunity has long been recognized, although the exact mechanistic relationship between these two phenomena remains unclear. In the present study we have found that vitiligo, the autoimmune destruction of melanocytes, generates self antigen required for mounting persistent and protective memory CD8+ T cell responses to melanoma. Vitiligo developed in approximately 60% of mice that were depleted of regulatory CD4+ T cells and then subjected to surgical excision of large established B16 melanomas. Mice with vitiligo generated 10-fold larger populations of CD8+ memory T cells specific for shared melanoma/melanocyte antigens. CD8+ T cells in mice with vitiligo acquired phenotypic and functional characteristics of effector memory, suggesting that they were supported by ongoing antigen stimulation. Such responses were not generated in melanocyte-deficient mice, indicating a requirement for melanocyte destruction in maintaining CD8+ T cell immunity to melanoma. Vitiligo-associated memory CD8+ T cells provided durable tumor protection, were capable of mounting a rapid recall response to melanoma, and did not demonstrate phenotypic or functional signs of exhaustion even after many months of exposure to antigen. This work establishes melanocyte destruction as a key determinant of lasting melanoma-reactive immune responses, thus illustrating that immune-mediated destruction of normal tissues can perpetuate adaptive immune responses to cancer.

Immune modulation effects of concomitant temozolomide and radiation therapy on peripheral blood mononuclear cells in patients with glioblastoma multiforme

Concomitant radiation therapy (RT) and temozolomide (TMZ) therapy after surgery is the standard treatment for glioblastoma multiforme (GBM). Radiation and chemotherapy can affect the immune system with implications on subsequent immune therapy. Therefore, we examined the phenotype and function of peripheral blood mononuclear cells in 25 patients with GBM prior to and 4 weeks after treatment with RT-TMZ using multicolor flow cytometry, as well as in vitro CD4(+) regulatory T cell (T(reg)) suppressor and dendritic cell maturation assays. RT-TMZ induced significant lymphopenia, with a decrease in total CD4(+) T cells, but did not significantly change monocyte counts. The proportion of functional T(reg) cells increased after treatment, whereas their absolute numbers remained stable. There was also a measurable decrease in the proportion of CD8(+)CD56(+) and absolute number of CD3(-)CD56(+) effector cells. Posttherapy monocytes retained the ability to mature into dendritic cells. Treatment with RT-TMZ is associated with changes in regulatory and effector peripheral blood mononuclear cells that tilt the balance towards an immune suppressive state. This shift can affect the outcome of immune therapy following RT-TMZ treatment and should be considered in the design of future combination therapy regimens.

A randomized trial of ex vivo CD40L activation of a dendritic cell vaccine in colorectal cancer patients: tumor-specific immune responses are associated with improved survival

PURPOSE

To determine whether an autologous dendritic cell (DC) vaccine could induce antitumor immune responses in patients after resection of colorectal cancer metastases and whether these responses could be enhanced by activating DCs with CD40L.

EXPERIMENTAL DESIGN

Twenty-six patients who had undergone resection of colorectal metastases were treated with intranodal injections of an autologous tumor lysate- and control protein [keyhole limpet hemocyanin (KLH)]-pulsed DC vaccine. Patients were randomized to receive DCs that had been either activated or not activated with CD40L. All patients were followed for a minimum of 5.5 years.

RESULTS

Immunization induced an autologous tumor-specific T-cell proliferative or IFNγ enzyme-linked immunospot response in 15 of 24 assessable patients (63%) and a tumor-specific DTH response in 61%. Patients with evidence of a vaccine-induced, tumor-specific T-cell proliferative or IFNγ response 1 week after vaccination had a markedly better recurrence-free survival (RFS) at 5 years (63% versus 18%, P = 0.037) than nonresponders. In contrast, no association was observed between induction of KLH-specific immune responses and RFS. CD40L maturation induced CD86 and CD83 expression on DCs but had no effect on immune responses or RFS.

CONCLUSION

Adjuvant treatment of patients after resection of colorectal metastases with an autologous tumor lysate-pulsed, DC vaccine-induced, tumor-specific immune responses in a high proportion of patients. There was an association between induction of tumor-specific immune responses and RFS. Activation of this DC vaccine with CD40L did not lead to increased immune responses.

Immune mobilization of autologous blood progenitor cells: direct influence on the cellular subsets collected

BACKGROUND AIMS

A phase I trial examined the ability of immunotherapy to mobilize progenitor and activated T cells.

METHODS

Interleukin (IL)-2 was administered subcutaneously for 11 days, with granulocyte (G)-colony-stimulating factor (CSF) (5 mcg/kg/day) and granulocyte-macrophage (GM)-CSF (7.5 mcg/kg/day) added for the last 5 days. Leukapheresis was initiated on day 11. Thirteen patients were treated (myeloma n = 11, non-Hodgkin's lymphoma n = 2).

RESULTS

Toxicities were minimal. IL-2 was stopped in two patients because of capillary leak (n = 1) and diarrhea (n = 1). Each patient required 2.5 leukaphereses (median; range 1-3) to collect 3.2 x 10⁶ CD34+ cells/kg (median; range 1.9-6.6 x 10⁶/kg). Immune mobilization increased the number of CD3+ CD8+ T cells (P = 0.002), CD56+ natural killer (NK) cells (P = 0.0001), CD8+ CD56+ T cells (P = 0.002) and CD4+ CD25+ cells (P = 0.0001) compared with cancer patients mobilized with G-CSF alone. There was increased lysis of myeloma cells after 7 days (P = 0.03) or 11 days (P = 0.02). The maximum tolerated dose of IL-2 was 1 x 10⁶ IU/m²/day.

CONCLUSIONS

Immune mobilization is well tolerated with normal subsequent marrow engraftment. As cells within the graft influence lymphocyte recovery, an increased number of functional lymphocytes may result in more rapid immune reconstitution.

Safety and efficacy of sorafenib in elderly patients treated in the North American advanced renal cell carcinoma sorafenib expanded access program

OBJECTIVE

In this retrospective analysis of the Advanced Renal Cell Carcinoma Sorafenib (ARCCS) program in North America, we compared the safety and efficacy of sorafenib in patients aged ≥70 with those aged <70 years.

METHODS

Patients were treated with oral sorafenib twice daily until the occurrence of disease progression or treatment intolerance. The primary objective of the ARCCS program was making sorafenib available to patients with advanced renal cell carcinoma (RCC) in the USA and Canada before marketing approval was obtained; the secondary objective was the evaluation of its safety and efficacy.

RESULTS

Of the 2,504 patients enrolled in the ARCCS program who received at least 1 dose of sorafenib, 736 (29%) were aged ≥70 years. The most common grade ≥3 adverse events included rash/desquamation (5% in both groups), hand-foot skin reaction (8% in those aged ≥70 years vs. 10% in those <70 years of age), hypertension (5 vs. 4%) and fatigue (7 vs. 4%). Partial response was seen in 4% of the patients in both age groups. The median overall survival for the ≥70-year versus <70-year groups was also similar (46 vs. 50 weeks).

CONCLUSIONS

There were no substantial differences in safety and efficacy between patients aged ≥70 and <70 years with advanced RCC treated with sorafenib.