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Purpose: Dynamic contrast-enhanced ultrasound (DCE-US) was used to monitor early response to sorafenib therapy in patients with liver metastases from uveal melanoma., Methods: In total, 21 patients with liver metastases were recruited within a prospective trial and underwent daily sorafenib therapy. DCE-US of a target lesion was performed before initiation of treatment, on day 15 and 56. Two independent blinded investigators performed software analysis for DCE-US parameters and inter-observer-correlation was calculated. Response to treatment was evaluated on day 56. DCE-US parameters were correlated with clinical response and RECIST1.1 criteria., Results: Inter-observer-correlation (r) of DCE-US parameters [time-to-peak (TTP), mean-transit-time (MTT), peak intensity (PI), regional blood volume (RBV), regional blood flow (RBF)] at baseline, day 15, and day 56 was highly significant (r-range 0.73-0.97, all p < 0.001). Out of 17 evaluable patients, 12 patients survived day 56 (clinical responders, cRE), whereas, five patients died before day 56 and were classified as non-responders (cNR). TTP values significantly increased in the cRE group 15 days after initiation of treatment for investigator 1 (p = 0.034) and at day 56 for both investigators (p = 0.028/0.028). MTT had increased significantly in the cRE group on day 56 (p = 0.037/0.022). In the cNR group changes for TTP and MTT remained insignificant. Thus, increase of the DCE-US parameters TTP and MTT are associated with response to treatment and prognosis., Conclusion: An increase of TTP and MTT at frequent intervals could serve as a surrogate marker for early response evaluation to anti-angiogenic treatment of metastatic uveal melanoma., (© 2021. The Author(s).)

Previous cancer vaccination trials often aimed to activate CD8(+) cytotoxic T-cell (CTL) responses with short (8-10mer) peptides and targeted CD4(+) helper T cells (TH) with HLA class II-binding longer peptides (12-16 mer) that were derived from tumor antigens. Accordingly, a study of immunomonitoring focused on the detection of CTL responses to the short, and TH responses to the long, peptides. The possible induction of concurrent TH responses to short peptides was widely neglected. In a recent phase I vaccination trial, 53 patients with different solid cancers were vaccinated with EMD640744, a cocktail of five survivin-derived short (9- or 10-mer) peptides in Montanide ISA 51VG. We monitored 49 patients and found strong CD8(+) T-cell responses in 63% of the patients. In addition, we unexpectedly found CD4(+) TH cell responses against at least two of the five short peptides in 61% (23/38) of the patients analyzed. The two peptides were recognized by HLA-DP4- and HLA-DR-restricted TH1 cells. Some short peptide-reactive (sp)CD4 T cells showed high functional avidity. Here, we show that a short peptide vaccine is able to activate a specific CD4(+) T-cell repertoire in many patients, facilitating a strong combined CD4(+)/CD8(+) T-cell response., (©2015 American Association for Cancer Research.)

Purpose: Survivin is a member of the inhibitor-of-apoptosis family. Essential for tumor cell survival and overexpressed in most cancers, survivin is a promising target for anti-cancer immunotherapy. Immunogenicity has been demonstrated in multiple cancers. Nonetheless, few clinical trials have demonstrated survivin-vaccine-induced immune responses., Experimental Design: This phase I trial was conducted to test whether vaccine EMD640744, a cocktail of five HLA class I-binding survivin peptides in Montanide(®) ISA 51 VG, promotes anti-survivin T-cell responses in patients with solid cancers. The primary objective was to compare immunologic efficacy of EMD640744 at doses of 30, 100, and 300 μg. Secondary objectives included safety, tolerability, and clinical efficacy., Results: In total, 49 patients who received ≥2 EMD640744 injections with available baseline- and ≥1 post-vaccination samples [immunologic-diagnostic (ID)-intention-to-treat] were analyzed by ELISpot- and peptide/MHC-multimer staining, revealing vaccine-activated peptide-specific T-cell responses in 31 patients (63 %). This cohort included the per study protocol relevant ID population for the primary objective, i.e., T-cell responses by ELISpot in 17 weeks following first vaccination, as well as subjects who discontinued the study before week 17 but showed responses to the treatment. No dose-dependent effects were observed. In the majority of patients (61 %), anti-survivin responses were detected only after vaccination, providing evidence for de novo induction. Best overall tumor response was stable disease (28 %). EMD640744 was well tolerated; local injection-site reactions constituted the most frequent adverse event., Conclusions: Vaccination with EMD640744 elicited T-cell responses against survivin peptides in the majority of patients, demonstrating the immunologic efficacy of EMD640744.

Oncolytic adenoviruses are emerging agents for treatment of cancer by tumor-restricted virus infection and cell lysis. Clinical trials have shown that oncolytic adenoviruses are well tolerated in patients but also that their antitumor activity needs improvement. A promising strategy toward this end is to trigger systemic and prolonged antitumor immunity by adenoviral oncolysis. Antitumor immune activation depends in large part on antigen presentation and T cell activation by dendritic cells (DCs). Thus, it is likely that the interaction of lysed tumor cells with DCs is a key determinant of such "oncolytic vaccination." Our study reveals that human DCs effectively phagocytose melanoma cells at late stages of oncolytic adenovirus infection, when the cells die showing preferentially features of necrotic cell death. Maturation, migration toward CCL19 and T cell stimulatory capacity of DCs, crucial steps for immune induction, were, however, not induced by phagocytosis of oncolysate, but could be triggered by a cytokine maturation cocktail. Therefore, oncolytic adenoviruses and adenoviral oncolysate did not block DC maturation, which is in contrast to reports for other oncolytic viruses. These results represent a rationale for inserting immunostimulatory genes into oncolytic adenovirus genomes to assure critical DC maturation. Indeed, we report here that adenoviral transduction of melanoma cells with CD40L during oncolysis triggers the maturation of human DCs with T cell stimulatory capacity similar to DCs matured by cytokines. We conclude that triggering and shaping DC-induced antitumor immunity by oncolytic adenoviruses "armed" with immunostimulatory genes holds promise for improving the therapeutic outcome of viral oncolysis in patients., (Copyright © 2011 UICC.)

Purpose: To investigate the therapeutic role of adjuvant vaccination with autologous mature dendritic cells (DC) loaded with tumor lysates derived from autologous, resected glioblastoma multiforme (GBM) at time of relapse., Experimental Design: Fifty-six patients with relapsed GBM (WHO grade IV) were treated with at least three vaccinations. Children and adults were treated similarly in three consecutive cohorts, with progressively shorter vaccination intervals per cohort. Feasibility and toxicity were assessed as well as effect of age, extent of resection, Karnofsky Performance Score, and treatment cohort on the progression-free (PFS) and overall survival (OS) using univariable and multivariable analysis., Results: Since the prevaccine reoperation, the median PFS and OS of the total group was 3 and 9.6 months, respectively, with a 2-year OS of 14.8%. Total resection was a predictor for better PFS both in univariable analysis and after correction for the other covariates. For OS, younger age and total resection were predictors of a better outcome in univariable analysis but not in multivariable analysis. A trend to improved PFS was observed in favor of the faster DC vaccination schedule with tumor lysate boosting. Vaccine-related edema in one patient with gross residual disease before vaccination was the only serious adverse event., Conclusion: Adjuvant DC-based immunotherapy for patients with relapsed GBM is safe and can induce long-term survival. A trend to PFS improvement was shown in the faster vaccination schedule. The importance of age and a minimal residual disease status at the start of the vaccination is underscored.

Background: Recent reports have demonstrated that the enzyme indoleamine 2,3-dioxygenase (IDO) is upregulated in human dendritic cells (DCs) upon in vitro maturation. IDO is supposed to convey immunosuppressive effects by degrading the essential amino acid tryptophan, thereby downregulating T-cell functions. Hence, we evaluated IDO expression in DC preparations used for therapeutic DC vaccination and its in vivo effects., Patients, Methods and Results: IDO expression was detected by real-time-PCR in a series of human clinical grade DCs (n = 28) prior to vaccination of advanced melanoma patients (n = 11). These analyses revealed an intra- and interpersonal variation in IDO mRNA levels. IDO was strongly upregulated in human DCs on RNA and on protein level upon in vitro maturation by Interleukin-1beta (IL-1beta), tumour necrosis factor-alpha (TNF-alpha), Interleukin-6 (IL-6) and Prostaglandin E2 (PGE2) over a time course of 24 h. The enzymatic activity of induced IDO was demonstrated by measuring tryptophan degradation. Moreover, in biopsies obtained 24 h after application of the DC vaccine a prominent infiltrate of IDO-positive cells was observed by immunohistochemistry. The inflammatory infiltrate of these sites stained positive for the transcription factor Forkhead box P3 (FoxP3), suggesting an IDO-mediated induction of regulatory T-cells. All analysed melanoma patients (n = 11) receiving DC based immunotherapy exhibited rapid disease progression with a short overall survival due to advanced tumour stage., Conclusion: The presented observations suggest a potential clinical relevance of IDO expression in DC-based therapeutic vaccines via the attraction or induction of FoxP3(+) T-cells.

Dendritic cells (DC) are promising tools for the immunotherapy of cancer. The induction of tumor-specific T cells and clinical regressions have already been observed in early phase I/II vaccination trials. As DC vaccination is now facing trials with larger patient collectives it becomes increasingly important to obtain large numbers of cells suitable for therapeutic applications under labor- and cost-effective conditions. We describe here a procedure that uses a novel cell separator (Elutra, Gambro BCT) to enrich monocytes from an entire apheresis product within one hour. Cells are separated on the basis of size and to a lesser extent density, by elutriation in a 40-ml conical chamber. The total monocyte recovery following elutriation (n = 6) was 98.53% (+/-8.07%), the recovery in the monocyte-rich fraction 75.45% (+/-11.31%), and the mean purity 82.95% (+/-6.01%). These monocytes can be cultured either in conventional culture dishes or in closed cell culture bags and differentiated, by using GM-CSF+IL-4 followed by a maturation cocktail composed of IL-1beta+IL-6+TNF-alpha+PGE2, into fully mature DC. The Elutra separator allows for fast and easy enrichment of monocytes within a closed system. Subsequently, elutriated monocytes can be successfully cultured into phenotypically and functionally mature DC for immunotherapeutic approaches. The method neither requires a density gradient step to enrich PBMC from leucapheresis products nor does it apply (xenogeneic) antibodies to target monocytes. Isolation of monocytes with Elutra may greatly facilitate future DC-based vaccination approaches.

Treatment of malignant glioma is difficult and discouraging. Even after resection and maximal adjuvant therapy, the prognosis remains poor. The authors sought a novel form of treatment, such as stimulating the patient's own immune response against the tumor, and developed a protocol of tumor vaccination in which autologous dendritic cells (DCs) were used in patients with recurrent malignant glioma. A 4-year-old girl was treated by means of biopsy sampling and radiotherapy for a rolandic low-grade glioma. Ten years later, a Grade III recurrence was discovered and treated with subtotal resection, interstitial radiation, six courses of oral temozolomide, and 12 courses of oral VP 16. At the end of the chemotherapy cycle, a new rapidly growing recurrence was diagnosed. A macroscopically complete resection was performed. Afterward, the girl was vaccinated with autologous DCs that had been pulsed ex vivo with the homogenate of the resection specimen. She received six vaccines in total. The efficacy of immunization was checked by a positive delayed-type hypersensitivity skin reaction after the second injection. After the fifth vaccine, a transient contrast enhancement without mass effect was visualized on magnetic resonance imaging. Simultaneously, positron emission tomography imaging revealed a transient increase of metabolic activity around the resection cavity, but the metabolic uptake ratio remained below 1.8. The patient's disease is still in complete remission 24 months after the last surgery. She is clinically well with minor and stable left hemiparesis. This case report illustrates the potential of vaccination with DCs loaded with crude tumor homogenate as adjuvant therapy to induce prolonged tumor control of malignant glioma and the objective noninvasively monitored immune response against infiltrating tumor cells.