Long-term follow-up of patients treated by adoptive transfer of melanoma tumor-infiltrating lymphocytes as adjuvant therapy for stage III melanoma

NIVO-TIL: combination anti-PD-1 therapy and adoptive T-cell transfer in untreated metastatic melanoma: an exploratory open-label phase I trial

BACKGROUND AND PURPOSE

In patients with metastatic melanoma who respond to anti-PD-1 therapy, the proliferation of intra-tumour CD8+ T cells is directly correlated with the clinical response, making tumour-infiltrating lymphocytes (TILs) a treatment of interest in combination with a PD-1 inhibitor, which is the undisputed gold standard in the management of metastatic melanoma. The aim of this trial was, therefore, to evaluate the safety and efficacy of sequential combination therapy consisting of nivolumab (a PD-1 inhibitor) and TILs adoptive T cells in patients with metastatic melanoma.

MATERIALS AND METHODS

We performed an exploratory, prospective, single-centre, open-label, non-randomised, uncontrolled phase I/II study. We enrolled 10 previously untreated patients with advanced melanoma. The treatment regimen was neoadjuvant anti-PD-1 therapy followed by 2 injections of TILs and a second sequence of anti-PD-1 therapy.

RESULTS AND INTERPRETATION

Among the four patients who received the autologous TILs + nivolumab combination, three (75%) achieved an objective response (two achieved a partial response [PR] at the end of the study, two achieved a complete response [CR]), and one achieved a CR at the end of the study. Among these three patients, one had a PR, and two had stable disease (SD) after the nivolumab course and before any TILs administration, reinforcing the importance of the tumour response after TILs injection. These responses were persistent, ranging from 9 months to 3.4 years.

Phase I study of adjuvant immunotherapy with autologous tumor-infiltrating lymphocytes in locally advanced cervical cancer

BACKGROUND

Adoptive cell therapy (ACT) with tumor-infiltrating lymphocytes (TILs) has achieved remarkable clinical efficacy in metastatic cancers such as melanoma and cervical cancer (CC). Here we explored the safety, feasibility and preliminary tumor response and performed translational investigations of adjuvant immunotherapy using infusion of autogenous (auto)-TILs following concurrent chemoradiotherapy (CCRT) in CC patients with locally advanced disease.

METHODS

Twenty-seven CC patients with stage III to IV disease were recruited in this single-center, phase I study. TILs were isolated from lesions in the uterine cervix and generated under good manufacturing practices (GMP) conditions and then infused after CCRT plus intramuscular interleukin (IL)-2 injections.

RESTULTS

From 27 patients, TILs were successfully expanded from 20 patients, with a feasibility of 74.1%. Twelve patients received TILs following CCRT. Adverse events (AEs) were primarily attributable to CCRT. Only 1 (8.3%) patient experienced severe toxicity with a grade 3 hypersensitivity reaction after TIL infusion. No autoimmune AEs, such as pneumonitis, hepatitis, or myocarditis, occurred, and there was no treatment-related mortality. Nine of 12 patients (75.0%) attained complete response, with a disease control duration of 9 to 22 months. Translational investigation showed that the transcriptomic characteristics of the infused TIL products and some immune biomarkers in the tumor microenvironment and serum of CC patients at baseline were correlated with the clinical response.

CONCULSION

TIL-based ACT following CCRT was safe in an academic center setting, with potential effective responses in locally advanced CC patients. 'Hot' inflammatory immune environments are beneficial to the clinical efficacy of TIL-based ACT as adjuvant therapy.

TRIAL REGISTRATION

CLINICALTRIALS

gov NCT04443296.

FUNDING

Natinoal Key R&D Program: Sci-Tech Key Program of the Guangzhou City Science Foundation; the Guangdong Provinve Sci-Tech International Key Program; the National Natural Science Foundation of China.

Cancer immunotherapy: Challenges and limitations

Although cancer immunotherapy has taken center stage in mainstream oncology inducing complete and long-lasting tumor regression, only a subset of patients receiving treatment respond and others relapse after an initial response. Different tumor types respond differently, and even in cancer types that respond (hot tumors), we still observe tumors that are unresponsive (cold tumors), suggesting the presence of resistance. Hence, the development of intrinsic or acquired resistance is a big challenge for the cancer immunotherapy field. Resistance to immunotherapy, including checkpoint inhibitors, CAR-T cell therapy, oncolytic viruses, and recombinant cytokines arises due to cancer cells employing several mechanisms to evade immunosurveillance.

Phase I/II clinical trial of adoptive cell transfer of sorted specific T cells for metastatic melanoma patients

Adoptive cell transfer (ACT) of tumor-specific T lymphocytes represents a relevant therapeutic strategy to treat metastatic melanoma patients. Ideal T-cells should combine tumor specificity and reactivity with survival in vivo, while avoiding autoimmune side effects. Here we report results from a Phase I/II clinical trial (NCT02424916, performed between 2015 and 2018) in which 6 metastatic HLA-A2 melanoma patients received autologous antigen-specific T-cells produced from PBMC, after peptide stimulation in vitro, followed by sorting with HLA-peptide multimers and amplification. Each patient received a combination of Melan-A and MELOE-1 polyclonal specific T-cells, whose specificity and anti-tumor reactivity were checked prior to injection, with subcutaneous IL-2. Transferred T-cells were also characterized in terms of functional avidity, diversity and phenotype and their blood persistence was evaluated. An increase in specific T-cells was detected in the blood of all patients at day 1 and progressively disappeared from day 7 onwards. No serious adverse events occurred after this ACT. Clinically, five patients progressed and one patient experienced a partial response following therapy. Melan-A and MELOE-1 specific T-cells infused to this patient were diverse, of high avidity, with a high proportion of T lymphocytes co-expressing PD-1 and TIGIT but few other exhaustion markers. In conclusion, we demonstrated the feasibility and safety of ACT with multimer-sorted Melan-A and MELOE-1 specific T cells to metastatic melanoma patients. The clinical efficacy of such therapeutic strategy could be further enhanced by the selection of highly reactive T-cells, based on PD-1 and TIGIT co-expression, and a combination with ICI, such as anti-PD-1.

Tumor infiltrating lymphocytes as adjuvant treatment in stage III melanoma patients with only one invaded lymph node after complete resection: results from a multicentre, randomized clinical phase III trial

BACKGROUND

Adoptive tumor-infiltrating lymphocytes (TIL) therapy and interleukin-2 (IL-2) have been investigated in melanoma.

AIM

To confirm previously observed preventive effects of TIL + IL2 in a subgroup of patients with relapsing metastatic stage III melanoma.

METHODOLOGY

Open-label, randomized two-group, multicenter five-year trial in adult stage III melanoma patients with only one invaded lymph node after complete resection. Patients received TIL + IL2 or abstention. TIL + IL2 was administered within 8 weeks after lymph node resection and 4 weeks after. Disease-free survival was assessed every 2 months up to month 18, every 3 months up to month 36 and every 4 months up to 5 years. A once-a-year follow-up was scheduled beyond the five-year follow-up. Safety was assessed throughout the trial.

RESULTS

Overall, 49 patients accounted for the modified intent-to-treat and 47 for the PP. Slightly more male than female patients participated; mean age was 57.7 ± 11.4 years in the TIL + IL2 group and 53.5 ± 13.0 years in the abstention group. After 5 years of follow-up, 11/26 patients in the TIL + IL2 group and 13/23 in the abstention group had relapsed. There was no statistical difference between the groups (HR: 0.63 CI 95% [0.28-1.41], p = 0.258), nine patients in the TIL + IL2 and 11 in the abstention group died with no significant difference between the two groups (HR: 0.65 CI95% [0.27 - 1.59], p = 0.34). Safety was good.

CONCLUSION

We did not confirm results of a previous trial. However, ulceration of the primary melanoma may be considered predictive of the efficacy of TIL in melanoma in adjuvant setting, in a manner similar to interferon α.

Adoptive transfer of tumor-infiltrating lymphocytes in melanoma: a viable treatment option

The treatment of metastatic melanoma patients with autologous tumor-infiltrating lymphocytes (TIL) shows robust, reproducible, clinical responses in clinical trials executed in several specialized centers over the world. Even in the era of targeted therapy and immune checkpoint inhibition, TIL therapy can be an additional and clinically relevant treatment line. This review provides an overview of the clinical experiences with TIL therapy thus far, including lymphodepleting regimens, the use of interleukin-2 (IL-2) and the associated toxicity. Characteristics of the TIL products and the antigen recognition pattern will be discussed, as well as the current and upcoming production strategies, including the selective expansion of specific fractions from the cell product. In addition, the future potential of TIL therapy in melanoma and other tumor types will be covered.

Adoptive Cell Therapy with Tumor-Infiltrating Lymphocytes in Advanced Melanoma Patients

Immunotherapy for melanoma includes adoptive cell therapy with autologous tumor-infiltrating lymphocytes (TILs). This monocenter retrospective study was undertaken to evaluate the efficacy and safety of this treatment of patients with advanced melanoma. All advanced melanoma patients treated with TILs using the same TIL expansion methodology and same treatment interleukin-2 (IL-2) regimen between 2009 and 2012 were included. After sterile intralesional excision of a cutaneous or subcutaneous metastasis, TILs were produced according to a previously described method and then infused into the patient who also received a complementary subcutaneous IL-2 regimen. Nine women and 1 man were treated for unresectable stage IIIC (n = 4) or IV (n = 6) melanoma. All but 1 patient with unresectable stage III melanoma (1st line) had received at least 2 previous treatments, including anti-CTLA-4 antibody for 4. The number of TILs infused ranged from 0.23 × 10⁹ to 22.9 × 10⁹. Regarding safety, no serious adverse effect was reported. Therapeutic responses included a complete remission, a partial remission, 2 stabilizations, and 6 progressions. Among these 4 patients with clinical benefit, 1 is still alive with 9 years of follow-up and 1 died from another cause after 8 years of follow-up. Notably, patients treated with high percentages of CD4 + CD25 + CD127lowFoxp3+ T cells among their TILs had significantly shorter OS. The therapeutic effect of combining TILs with new immunotherapies needs further investigation.

Learning from the Proteasome How To Fine-Tune Cancer Immunotherapy

Cancer immunotherapy has recently emerged as a forefront strategy to fight cancer. Key players in antitumor responses are CD8⁺ cytolytic T lymphocytes (CTLs) that can detect tumor cells that carry antigens, in other words, small peptides bound to surface major histocompatibility complex (MHC) class I molecules. The success and safety of cancer immunotherapy strategies depends on the nature of the antigens recognized by the targeted T cells, their strict tumor specificity, and whether tumors and antigen-presenting cells can efficiently process the peptide. We review here the nature of the tumor antigens and their potential for the development of immunotherapeutic strategies. We also discuss the importance of proteasome in the production of these peptides in the context of immunotherapy and therapeutic cancer vaccines.

Efficacy of Tumor-Infiltrating Lymphocytes Combined with IFN-α in Chinese Resected Stage III Malignant Melanoma

Background

This study aims to explore the efficacy of tumor-infiltrating lymphocytes (TIL) along with interferon-α (IFN-α) to treat stage III malignant melanoma (MM) patients in China.

Methods

Between May 2010 and October 2014, 77 patients of stage III MM who underwent surgery were collected in this study. These patients were divided into two groups: patients who received TIL + IFN-α ± RetroNectin-activated cytokine-induced killer cells (R-CIK) in Arm 1 (n = 27) and IFN-α ± R-CIK in Arm 2 (n = 50) as adjuvant therapy. The primary endpoints were disease-free survival (DFS) time and DFS rates measured at time points of 1, 2, and 3 years. The secondary endpoints were overall survival (OS) rates measured at time points of 1, 2, 3, and 5 years as well as OS as evaluated by Kaplan-Meier.

Results

Our results indicated that the median DFS and OS in Arm 1 were significantly better than those in Arm 2. The data also demonstrated that DFS rate and OS rates in Arm 1 were significantly better than those in Arm 2 at all measured time points.

Conclusion

Patients who undergo surgical excision of stage III MM appear to enjoy prolonged DFS and OS when treated with TIL + IFN-α compared to IFN-α alone.

Skewed Differentiation of Circulating Vγ9Vδ2 T Lymphocytes in Melanoma and Impact on Clinical Outcome

Objective

The aim of this study was to evaluate over time circulating γδ T lymphocytes in melanoma patients in terms of frequency, effector functions, and relationship with clinical stage and evolution, by comparing preoperative values to those obtained at a mean follow-up of 36 months or in the event of recurrence or disease progression, and to those of healthy controls. Also, we correlated the presence of tumor-infiltrating γδ T lymphocytes with clinical evolution of melanoma.

Results

Mean frequencies of circulating γδ T cells before and after melanoma removal were very similar and comparable to healthy subjects, but patients who progressed to stage III or IV showed a significantly decreased frequency of circulating Vγ9Vδ2 T cells. The distribution of Vγ9Vδ2 memory and effector subsets was similar in healthy subjects and melanoma patients at diagnosis, but circulating γδ T cells of patients after melanoma removal had a skewed terminally-differentiated effector memory phenotype. Highly suggestive of progressive differentiation toward a cytotoxic phenotype, Vγ9Vδ2T cells from patients at follow up had increased cytotoxic potential and limited cytokine production capability, while the opposite pattern was detected in Vγ9Vδ2T cells from patients before melanoma removal.

Conclusions

Follow-up data also showed that tumor infiltrating γδ T cells were significantly associated with lower mortality and relapse rates, suggesting that they may serve as a prognostic biomarker, for human melanoma.

Activated cytotoxic T-lymphocyte immunotherapy is effective for advanced oral and maxillofacial cancers

Conventional cancer treatments are surgery, radiotherapy, and chemotherapy, but treatment efficiency is insufficient and cancer recurrence is common. Immunotherapy has been added as an important cancer treatment component, but no reports on its efficacy in oral and maxillofacial cancers exist. We evaluated the clinical efficacy of adoptive immunotherapy using ex vivo-activated cytotoxic T lymphocytes (CTL) in the treatment of 7 patients with advanced oral and maxillofacial cancers with stage IV disease at diagnosis. The mean follow-up period was 26.2 months. Phenotype of the lymphocyte assay revealed that the percentage of CD4(+) T cells decreased and that of CD8(+) T cells increased among infused lymphocytes compared to that in unstimulated peripheral blood mononuclear cells (PBMCs), and infused lymphocytes produced a significantly higher level of IFN-γ than PBMCs or tumor cells alone. In a representative patient who refused surgery tumor regression was confirmed after CTL infusion. Computed tomography clearly indicated a significant reduction in tumor size followed by the complete disappearance of the tumor. Histological examination showed that the cancers in patients receiving CTL therapy were heavily infiltrated with lymphocytes. The other 2 patients who received CTL therapy as adjuvant therapy showed neither recurrent disease nor new disease lesions. The 1-year survival rates showing response and those with progressive disease were 100 and 25%, respectively. Moreover, no significant adverse reactions were reported during the study period. CTL therapy remains in the early stages of treatment options, but it has potential as a valuable treatment and improvement of quality of life for patients with otherwise incurable cancers.

Tumour antigens recognized by T lymphocytes: at the core of cancer immunotherapy

In this Timeline, we describe the characteristics of tumour antigens that are recognized by spontaneous T cell responses in cancer patients and the paths that led to their identification. We explain on what genetic basis most, but not all, of these antigens are tumour specific: that is, present on tumour cells but not on normal cells. We also discuss how strategies that target these tumour-specific antigens can lead either to tumour-specific or to crossreactive T cell responses, which is an issue that has important safety implications in immunotherapy. These safety issues are even more of a concern for strategies targeting antigens that are not known to induce spontaneous T cell responses in patients.

Adoptive TIL transfer in the adjuvant setting for melanoma: long-term patient survival

Two first analyses of our clinical trial on TIL as adjuvant therapy for melanoma were published in 2002 and 2007. We present here an update of the clinical results after a 17-year median followup. In this trial, disease-free patients were randomly assigned to receive either TIL/IL-2 or IL-2. The relapse-free survival (RFS) was the primary objective. Eighty-eight patients were enrolled. A new analysis performed in May 2013 did not show significant changes in RFS or OS duration. However, our first finding on the association between the number of invaded lymph nodes and TIL effectiveness was strengthened. The Cox model adjusted on this interaction showed for the first time a significant treatment effect when considering the overall population, both on the RFS and OS. Patients treated with TIL had a longer RFS (P = 0.023) or OS (P = 0.020). This study being with a very long followup (17 years), confirmed the association between TIL effectiveness and the number of invaded lymph nodes, indicating that a low tumor burden could be a crucial factor enhancing the curative effect of TIL in possible microscopic residual disease. Moreover, we confirmed that a prolonged survival was associated with the presence of specific TIL and a decrease in Foxp3 expression.

A full GMP process to select and amplify epitope-specific T lymphocytes for adoptive immunotherapy of metastatic melanoma

A number of trials of adoptive transfer of tumor-specific T lymphocytes have been performed in the last 20 years in metastatic melanoma, with increasingly encouraging results as the relevant melanoma antigens were identified and the purity/specificity of injected T cells improved. We have previously described a sorting method of epitope-specific T lymphocytes that uses magnetic beads coated with HLA/peptide complexes and we suggested that this method could be applied to a clinical setting. In the present work, we provide a detailed description of the whole GMP process of sorting and amplification of clinical grade T cells specific for the melanoma antigens Melan-A and MELOE-1. All the reagents used in this process including the sorting reagent were produced in GMP conditions and we document the optimization of the different steps of the process such as peptide stimulation, sorting, and amplification. The optimized procedure, validated in 3 blank runs in a clinical setting, allowed the production of at least 10⁸ pure (>90%) Melan-A- and MELOE-1-specific T cells within 28 days starting with 100 mL of blood from metastatic melanoma patients. This GMP process is thus ready to be used in an upcoming phase I/II clinical trial on metastatic melanoma patients.

Tissue biomarkers in melanoma patients treated with TIL

While treating stage III melanoma patients with autologous therapeutic TIL in an adjuvant setting, we previously reported a significant benefit of treatment on both progression-free survival and overall survival in patients with only one invaded lymph node (early stage III) compared to patients with more than one invaded lymph nodes (advanced stage III). In this context, in order to understand the difference of activity of TIL therapy according to the progression of the illness at stage III, the first objective of the present study was to determine potential differences in the characteristics of TIL populations obtained from an early stage III and a more advanced stage III when tumor burden is more important. The second objective was to determine possible differences in tissue expression level of several molecules involved in interactions between tumor cells and T cells between early and advanced stage III considering that the tumor microenvironment of invaded lymph nodes could become more tolerant with the progression of the disease. A total of 47 samples of melanoma invaded LN from stage IIIb (AJCC 2007) melanoma patients treated with TIL plus IL-2 were included in this study. We confirmed that both PFS and OS were significantly associated to the presence of tumor-reactive T-cells among TIL injected to the patients and that these tumor reactive T cells were more frequently observed at the early stage III. Moreover, while analyzing the expression of 17 markers on 34/47 tumor specimens using immunohistochemistry, we identified that 3 tissue markers involved in interactions between melanoma cells and T cells have a significant difference of expression between early and advanced stage III: MHC class I, adhesion molecule ICAM-1 and the co-stimulation molecule LFA-3 had a significantly weaker expression in melanoma tissue specimens from advanced stage III. In addition, the expression of the alpha chain of the IL-2 receptor (CD25) and the nuclear transcription factor Foxp3 was significantly increased in the melanoma tissue specimens from advanced stage III. Our results suggest differences in the immunological status of the tumor microenvironment between early and advanced stage III, which could explain the difference in clinical response to TIL infusion in an adjuvant setting between early and advanced stage III.

Potent antitumor effects of combination therapy with IFNs and monocytes in mouse models of established human ovarian and melanoma tumors

Interferon-activated monocytes are known to exert cytocidal activity against tumor cells in vitro. Here, we have examined whether a combination of IFN-α2a and IFN-γ and human monocytes mediate significant antitumor effects against human ovarian and melanoma tumor xenografts in mouse models. OVCAR-3 tumors were treated i.t. with monocytes alone, IFN-α2a and IFN-γ alone or combination of all three on day 0, 15 or 30 post-tumor implantation. Mice receiving combination therapy beginning day 15 showed significantly reduced tumor growth and prolonged survival including complete regression in 40% mice. Tumor volumes measured on day 80 in mice receiving combination therapy (206 mm(3)) were significantly smaller than those of mice receiving the IFNs alone (1,041 mm(3)), monocytes alone (1,111 mm(3)) or untreated controls (1,728 mm(3)). Similarly, combination therapy with monocytes and IFNs of much larger tumor also inhibited OVCAR-3 tumor growth. Immunohistochemistry studies showed a large number of activated macrophages (CD31(+)/CD68(+)) infiltrating into OVCAR-3 tumors and higher densities of IL-12, IP10 and NOS2, markers of M1 (classical) macrophages in tumors treated with combination therapy compared to the controls. Interestingly, IFNs-activated macrophages induced apoptosis of OVCAR-3 tumor cells as monocytes alone or IFNs alone did not mediate significant apoptosis. Similar antitumor activity was observed in the LOX melanoma mouse model, but not as profound as seen with the OVCAR-3 tumors. Administration of either mixture of monocytes and IFN-α2a or monocytes and IFN-γ did not inhibit Lox melanoma growth; however, a significant inhibition was observed when tumors were treated with a mixture of monocytes, IFN-α2a and IFN-γ. These results indicate that monocytes and both IFN-α2a and IFN-γ may be required to mediate profound antitumor effect against human ovarian and melanoma tumors in mouse models.

Antigen-specific versus antigen-nonspecific immunotherapeutic approaches for human melanoma: the need for integration for optimal efficacy?

Due to its immunogenecity and evidence of immune responses resulting in tumor regression, metastatic melanoma has been the target for numerous immunotherapeutic approaches. Unfortunately, based on the clinical outcomes, even the successful induction of tumor-specific responses does not correlate with efficacy. Immunotherapies can be divided into antigen-specific approaches, which seek to induce T cells specific to one or several known tumor associated antigens (TAA), or with antigen-nonspecific approaches, which generally activate T cells to become nonspecifically lytic effectors. Here the authors critically review the different immunotherapeutic approaches in melanoma.

Adoptive transfer with high-affinity TCR to treat human solid tumors: how to improve the feasibility?

The adoptive transfer of tumor antigen-specific T cells recently achieved clinical efficacy for a fraction of melanoma patients refractory to other therapies. Unfortunately, the application of this strategy to the remaining melanoma and most other cancer patients is hampered by the difficulty to generate high-affinity tumor-reactive T cells. Two strategies are currently developed to extend the feasibility of this therapeutic approach: clinical grade tool production for MHC-peptide multimer-driven sorting of antigen-specific T cells from the endogenous peripheral T cell repertoire and de novo engineering of the missing repertoire by genetic transfer of cloned specific T cell receptor (TCR) into T cells. The expected multiplication of adoptive transfer treatments, by these strategies, and their careful evaluation should enable the cure of a number of otherwise compromised cancer patients and to gain insight into the characteristics of transferred T cells best fitted to eradicate tumor cells, in terms of antigen specificities, phenotype, and functions. In particular, identification of tumor-rejection antigens by this approach would improve the design and efficacy of all immunotherapeutic approaches.

Near eradication of clinically relevant concentrations of human tumor cells by interferon-activated monocytes in vitro

We have previously reported that low concentrations of interferon (IFN)-activated monocytes exert near-eradicative cytocidal activity against low concentrations of several human tumor cells in vitro. In the present study, we examined 7 human tumor cell lines and 3 diploid lines in the presence or absence of 10 ng/mL IFNα2a and monocytes. The results confirmed strong cytocidal activity against 4 of 7 tumor lines but none against 3 diploid lines. To model larger in vivo tumors, we increased the target cell concentration and determined the concentration of IFNα2a and monocytes, required for cell death. We found that increasing the tumor cell concentration from 10- to 100-fold (10(5) cells/well) required an increase in the concentration of IFNs by over 100-fold and monocytes by 10-fold. High concentrations of monocytes could sometimes kill tumor or diploid cells in the absence of IFN. We may conclude that killing of high concentrations of tumor or diploid cells required high concentrations of monocytes that could sometimes kill in the absence of IFN. Thus, high concentrations of tumor cells required high concentrations of IFN and monocytes to cause near eradication of tumor cells. These findings may have clinical implications.

Cancer immunotherapy

Cancer immunotherapy consists of approaches that modify the host immune system, and/or the utilization of components of the immune system, as cancer treatment. During the past 25 years, 17 immunologic products have received regulatory approval based on anticancer activity as single agents and/or in combination with chemotherapy. These include the nonspecific immune stimulants BCG and levamisole; the cytokines interferon-α and interleukin-2; the monoclonal antibodies rituximab, ofatumumab, alemtuzumab, trastuzumab, bevacizumab, cetuximab, and panitumumab; the radiolabeled antibodies Y-90 ibritumomab tiuxetan and I-131 tositumomab; the immunotoxins denileukin diftitox and gemtuzumab ozogamicin; nonmyeloablative allogeneic transplants with donor lymphocyte infusions; and the anti-prostate cancer cell-based therapy sipuleucel-T. All but two of these products are still regularly used to treat various B- and T-cell malignancies, and numerous solid tumors, including breast, lung, colorectal, prostate, melanoma, kidney, glioblastoma, bladder, and head and neck. Positive randomized trials have recently been reported for idiotype vaccines in lymphoma and a peptide vaccine in melanoma. The anti-CTLA-4 monoclonal antibody ipilumumab, which blocks regulatory T-cells, is expected to receive regulatory approval in the near future, based on a randomized trial in melanoma. As the fourth modality of cancer treatment, biotherapy/immunotherapy is an increasingly important component of the anticancer armamentarium.

Value of large scale expansion of tumor infiltrating lymphocytes in a compartmentalised gas-permeable bag: interests for adoptive immunotherapy

BACKGROUND

Adoptive cell therapy (ACT) has emerged as an effective treatment for patients with metastatic melanoma. However, there are several logistical and safety concerns associated with large-scale ex vivo expansion of tumour-specific T lymphocytes for widespread availability of ACT for cancer patients. To address these problems we developed a specific compartmentalised bag allowing efficient expansion of tumour-specific T lymphocytes in an easy handling, closed system.

METHODS

Starting from lymph nodes from eight melanoma patients, we performed a side-by-side comparison of Tumour-Infiltrating Lymphocytes (TIL) produced after expansion in the compartmentalised bag versus TIL produced using the standard process in plates. Proliferation yield, viability, phenotype and IFNγ secretion were comparatively studied.

RESULTS

We found no differences in proliferation yield and cell viability between both TIL production systems. Moreover, each of the cell products complied with our defined release criteria before being administered to the patient. The phenotype analysis indicated that the compartmentalised bag favours the expansion of CD8+ cells. Finally, we found that TIL stimulated in bags were enriched in reactive CD8+ T cells when co-cultured with the autologous melanoma cell line.

CONCLUSIONS

The stimulation of TIL with feeder cells in the specifically designed compartmentalised bag can advantageously replace the conventional protocol using plates. In particular, the higher expansion rate of reactive CD8+ T cells could have a significant impact for ACT.

Is antigen specificity the key to efficient adoptive T-cell therapy?

Adoptive transfer of T cells remains a promising approach in melanoma. Initial clinical trials performed with polyclonal tumor-infiltrating lymphocyte gave limited clinical results. Nonetheless, encouraging results have been reported in adjuvant setting (stage III melanoma), and when tumor-infiltrating lymphocytes were associated with lymphodepleting regimens. Specificity of adoptive cell therapy has been achieved with the infusion of antigen specific cytotoxic T-lymphocyte clones, associated with some clinical responses. Antigen specificity can also be obtained by the allogeneic transfer of high-avidity T-cell receptors into autologous T cells. We propose an alternative strategy based on the selection of antigen-specific T cells with magnetic beads coated with HLA–peptide multimers. Future improvements of adoptive melanoma immunotherapy may be achieved by its association with other therapeutic strategies such as targeted therapy against signaling pathways.

Matrix metalloproteinase-2 conditions human dendritic cells to prime inflammatory T(H)2 cells via an IL-12- and OX40L-dependent pathway

Matrix metalloproteinase-2 (MMP-2) is a proteolytic enzyme degrading the extracellular matrix and overexpressed by many tumors. Here, we documented the presence of MMP-2-specific CD4(+) T cells in tumor-infiltrating lymphocytes (TILs) from melanoma patients. Strikingly, MMP-2-specific CD4(+) T cells displayed an inflammatory T(H)2 profile, i.e., mainly secreting TNF-α, IL-4, and IL-13 and expressing GATA-3. Furthermore, MMP-2-conditioned dendritic cells (DCs) primed naïve CD4(+) T cells to differentiate into an inflammatory T(H)2 phenotype through OX40L expression and inhibition of IL-12p70 production. MMP-2 degrades the type I IFN receptor, thereby preventing STAT1 phosphorylation, which is necessary for IL-12p35 production. Active MMP-2, therefore, acts as an endogenous type 2 "conditioner" and may play a role in the observed prevalence of detrimental type 2 responses in melanoma.

Is primary melanoma ulceration a factor of good response to adoptive immunotherapy?

BACKGROUND

Primary melanoma ulceration is a factor of poor prognosis at the local and regional stage. The physiopathological mechanisms which explain its prognostic impact are still little known. However, two recent studies suggest that it could be a predictive factor of good response to a non-specific immunotherapy (interferon-alpha) and to an active immunotherapy (vaccine).

OBJECTIVE

The aim of this study was to determine whether ulceration could be a factor of good prognosis in the context of an adoptive immunotherapy with tumour infiltrating lymphocytes (TIL) in stage III regional lymph node metastatic melanoma (sixth American Joint Committee on Cancer staging system) and whether it was associated with an improvement in the effectiveness of this treatment compared with the control group.

METHODS

We have included all the patients treated in open prospective randomized TIL vs. control protocols in our unit from 1997 to 2009. Clinical data were derived retrospectively from patient files. Statistical analysis was performed using log-rank tests, Cox models and tests for interaction.

RESULTS

A total of 144 patients were included. In the group of 80 patients treated with TIL, primary melanoma ulceration remained a pejorative factor for relapse-free and overall survival in univariate and multivariate analysis. The presence of ulceration did not change the effectiveness of TIL treatment in comparison with the control group with regards to relapse-free and overall survival.

CONCLUSION

Our study demonstrates that primary melanoma ulceration does not have any impact on the response to TIL adoptive immunotherapy and thus does not confirm its positive prognostic value suggested by two other immunotherapy approaches.

Current immunotherapy for solid tumors

Explorative knowledge of cellular and molecular mechanisms of immune function and regulation has provided optimism in developing cancer immunotherapy. However, three decades of experimental and clinical investigations to offer powerful immunotherapeutic strategies against solid tumors, with the possible exception of monoclonal antibody-targeted therapies, have not succeeded in significantly prolonging patient survival. Nonspecific immune approaches, including cytokine-based therapies and allogeneic hematopoietic stem cell transplantation, have so far produced consistent, although limited, results. In this review, we present the developments of cell transfer-based strategies that, in preclinical studies, have demonstrated potential efficacy, but have only established tumor regression in limited numbers of patients. The key to success demands creative combinations of tumor antigens, adjuvance, gene modification and various administration strategies in the development of cell-based therapies together with other cancer-treatment principles, often in a stepwise 'space-rocket-type' approach. Combined efforts of several scientific disciplines, such as tumor biology and immunology, as well as cell and gene research in transplantation, will open new venues. New regulation for clinical trials with advanced therapy medicine products to ensure patient safety will be highlighted.

[Skin cancer: what's new in clinical research?]

Every year skin cancer is the subject of many publications. In this review of the recent literature, we selected epidemiological, clinical, and therapeutic data published between October 2006 and September 2007. Some of the studies presented in conferences in 2007 are also mentioned. New epidemiological data have been provided regarding the incidence of different types of skin cancers, the effect of certain risk factors or drug or food protective factors, the overall improvement of survival in melanoma, the epidemiological, clinical, and/or therapeutic particularities of rapidely growing melanomas and thick melanomas, and the relations between sun exposure, skin cancers, and other solid tumors. New prognostic studies in melanoma have improved the evaluation of prognosis in specific situations such as thin melanoma, acrolentiginous melanoma, and melanoma with positive sentinel lymph nodes (depending on the type of positivity) or negative sentinel lymph nodes. Important results on adjuvant interferon in melanoma have been presented. Clinical trials evaluating new therapeutic approaches in stage III and IV melanoma are going on. Several studies confirmed the clinical benefit of adjuvant irradiation on the tumor site in Merkel cell carcinoma. New treatments are being studied or have been approved in refractory forms of cutaneous T-cell lymphoma and in inoperable forms of squamous cell carcinoma and dermatofibrosarcoma protuberans.

MELOE-1 is a new antigen overexpressed in melanomas and involved in adoptive T cell transfer efficiency

A cytotoxic T lymphocyte (CTL) clone was derived from a tumor-infiltrating lymphocyte (TIL) population infused to a melanoma patient who remained relapse free for 10 yr after this adoptive transfer. This clone recognized all melanoma cell lines tested and, to a lower extent, melanocytes, in the context of human histocompatibility leukocyte antigen A2 (HLA-A2), but it did not recognize other tumor cell types. The gene coding for the antigen recognized by this clone was identified by the screening of a melanoma complementary DNA expression library. This antigen is overexpressed in melanomas, compared with other cancer cell lines and healthy tissues, and was thus called melanoma-overexpressed antigen (meloe). Remarkably, the structure of meloe was unusual, with multiple short open reading frames (ORFs). The peptide recognized by the CTL clone was encoded by one of these ORFs, called MELOE-1. Using a specific HLA-A2/peptide tetramer, we showed a correlation between the infusion of TILs containing MELOE-1–specific T cells and relapse prevention in HLA-A2 patients. Indeed, 5 out of 9 patients who did not relapse were infused with TILs that contained MELOE-1–specific T cells, whereas 0 out of the 21 patients who relapsed was infused with such TIL-containing lymphocytes. Overall, our results suggest that this new antigen is involved in immunosurveillance and, thus, represents an attractive target for immunotherapy protocols of melanoma.

TGF beta secreted by B16 melanoma antagonizes cancer gene immunotherapy bystander effect

Tumor-targeted delivery of immune stimulatory genes, such as pro-inflammatory cytokines and suicide genes, has shown to cure mouse models of cancer. Total tumor eradication was also found to occur despite subtotal tumor engineering; a phenomenon coined the "bystander effect". The bystander effect in immune competent animals arises mostly from recruitment of a cancer lytic cell-mediated immune response to local and distant tumor cells which escaped gene modification. We have previously described a Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF) and Interleukin 2 (IL2) fusokine (aka GIFT2) which serves as a potent anticancer cytokine and it here served as a means to understand the mechanistic underpinnings to the immune bystander effect in an immune competent model of B16 melanoma. As expected, we observed that GIFT2 secreted by genetically engineered B16 tumor cells induces a bystander effect on non modified B16 cells, when admixed in a 1:1 ratio. However, despite keeping the 1:1 ratio constant, the immune bystander effect was completely lost as the total B16 cell number was increased from 10(4) to 10(6) which correlated with a sharp reduction in the number of tumor-infiltrating NK cells. We found that B16 secrete biologically active TGFbeta which in turn inhibited GIFT2 dependent immune cell proliferation in vitro and downregulated IL-2R beta expression and IFN gamma secretion by NK cells. In vivo blockade of B16 originating TGFbeta significantly improved the immune bystander effect arising from GIFT2. We propose that cancer gene immunotherapy of pre-established tumors will be enhanced by blockade of tumor-derived TGFbeta.

Aberrant expression of BCL2A1-restricted minor histocompatibility antigens in melanoma cells: application for allogeneic transplantation

It has been shown that allogeneic hematopoietic stem cell transplantation (HSCT) can be one of the therapeutic options for patients with metastatic solid tumors, such as renal cancer. However, the development of relatively severe GVHD seems to be necessary to achieve tumor regression in the current setting. Thus, it is crucial to identify minor histocompatibility antigens (mHags) only expressed in tumor cells but not GVHD target organs. In this study, we examined whether three mHags: ACC-1 and ACC-2 encoded by BCL2A1, and HA-1 encoded by HMHA1, could serve as such targets for melanoma. Real-time PCR and immunohistochemical analysis revealed that the expression of both BCL2A1and HMHA1 in melanoma cell lines and primary melanoma cells was comparable to that of hematopoietic cells. Indeed, melanoma cell lines were efficiently lysed by cytotoxic T lymphocytes specific for ACC-1, ACC-2, and HA-1. Our data suggest that targeting mHags encoded not only by HMHA1, whose aberrant expression in solid tumors has been reported, but also BCL2A1 may bring about beneficial selective graft-versus-tumor effects in a population of melanoma patients for whom these mHags are applicable.