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T‐cells specific for foreign (e.g., viral) antigens can give rise to strong protective immune responses, whereas self/tumor antigen‐specific T‐cells are thought to be less powerful. However, synthetic T‐cell vaccines composed of Melan‐A/MART‐1 peptide, CpG and IFA can induce high frequencies of tumor‐specific CD8 T‐cells in PBMC of melanoma patients. Here we analyzed the functionality of these T‐cells directly ex vivo, by multiparameter flow cytometry. The production of multiple cytokines (IFNγ, TNFα, IL‐2) and upregulation of LAMP‐1 (CD107a) by tumor (Melan‐A/MART‐1) specific T‐cells was comparable to virus (EBV‐BMLF1) specific CD8 T‐cells. Furthermore, phosphorylation of STAT1, STAT5 and ERK1/2, and expression of CD3 zeta chain were similar in tumor‐ and virus‐specific T‐cells, demonstrating functional signaling pathways. Interestingly, high frequencies of functionally competent T‐cells were induced irrespective of patient's age or gender. Finally, CD8 T‐cell function correlated with disease‐free survival. However, this result is preliminary since the study was a Phase I clinical trial. We conclude that human tumor‐specific CD8 T‐cells can reach functional competence in vivo, encouraging further development and Phase III trials assessing the clinical efficacy of robust vaccination strategies.

Purpose: Cancer vaccines aim to generate and maintain antitumor immune responses. We designed a phase I/IIa clinical trial to test a vaccine formulation composed of Montanide ISA-51 (Incomplete Freund's Adjuvant), LAG-3Ig (IMP321, a non-Toll like Receptor agonist with adjuvant properties), and five synthetic peptides derived from tumor-associated antigens (four short 9/10-mers targeting CD8 T-cells, and one longer 15-mer targeting CD4 T-cells). Primary endpoints were safety and T-cell responses.Experimental Design: Sixteen metastatic melanoma patients received serial vaccinations. Up to nine injections were subcutaneously administered in three cycles, each with three vaccinations every 3 weeks, with 6 to 14 weeks interval between cycles. Blood samples were collected at baseline, 1-week after the third, sixth and ninth vaccination, and 6 months after the last vaccination.Circulating T-cells were monitored by tetramer staining directly ex vivo, and by combinatorial tetramer and cytokine staining on in vitro stimulated cells.Results: Side effects were mild to moderate, comparable to vaccines with Montanide alone. Specific CD8 T-cell responses to at least one peptide formulated in the vaccine preparation were found in 13 of 16 patients. However, two of the four short peptides of the vaccine formulation did not elicit CD8 T-cell responses. Specific CD4 T-cell responses were found in all 16 patients.Conclusions: We conclude that vaccination with IMP321 is a promising and safe strategy for inducing sustained immune responses, encouraging further development for cancer vaccines as components of combination therapies.

Background: The risk of osteoporosis and fracture influences the selection of adjuvant endocrine therapy. We analyzed bone mineral density (BMD) in Swiss patients of the Breast International Group (BIG) 1-98 trial [treatment arms: A, tamoxifen (T) for 5 years; B, letrozole (L) for 5 years; C, 2 years of T followed by 3 years of L; D, 2 years of L followed by 3 years of T].Patients and methods: Dual-energy X-ray absorptiometry (DXA) results were retrospectively collected. Patients without DXA served as control group. Repeated measures models using covariance structures allowing for different times between DXA were used to estimate changes in BMD. Prospectively defined covariates were considered as fixed effects in the multivariable models.Results: Two hundred and sixty-one of 546 patients had one or more DXA with 577 lumbar and 550 hip measurements.Weight, height, prior hormone replacement therapy, and hysterectomy were positively correlated with BMD; the correlation was negative for letrozole arms (B/C/D versus A), known osteoporosis, time on trial, age, chemotherapy, and smoking. Treatment did not influence the occurrence of osteoporosis (T score < 22.5 standard deviation).Conclusions: All aromatase inhibitor regimens reduced BMD. The sequential schedules were as detrimental for bone density as L monotherapy.