Rom Leidner

Responses of metastatic basal cell and cutaneous squamous cell carcinomas to anti-PD1 monoclonal antibody REGN2810

BackgroundBasal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (CSCC) share exposure to UV light as the dominant risk factor, and these tumors therefore harbor high mutation burdens. In other malignancies, high mutation burden has been associated with clinical benefit from therapy with antibodies directed against the Programmed Death 1 (PD-1) immune checkpoint receptor. Highly mutated tumors are more likely to express immunogenic tumor neoantigens that attract effector T cells, which can be unleashed by blockade of the PD-1 immune checkpoint.Case presentationsThis report describes a patient with metastatic BCC and a patient with metastatic CSCC who were treated with REGN2810, a fully human anti-PD-1 monoclonal antibody, in an ongoing phase 1 trial (NCT02383212). The CSCC patient has experienced an ongoing complete response (16+ months), and the BCC patient has experienced an ongoing partial response (12+ months).ConclusionsThese case reports suggest that UV-associated skin cancers, beyond melanoma, are sensitive to PD-1 blockade.Trial registrationClinicaltrials.gov NCT02383212. Registered 2 February 2015.

OX40, PD-1 and CTLA-4 are selectively expressed on tumor-infiltrating T cells in head and neck cancer

The tumor microenvironment of squamous cell carcinoma of the head and neck (SCCHN) has been shown to be immune suppressive. Therefore, strategies aimed at overcoming this issue could have a positive therapeutic impact. Hence, we investigated the expression of the known immune‐modulatory proteins OX40, programmed cell death protein 1 (PD‐1) and cytotoxic T‐lymphocyte‐associated protein 4 (CTLA‐4) in SCCHN on different T‐cell subsets of tumor‐infiltrating lymphocytes (TIL) to ascertain whether these proteins could potentially be targeted alone or in combination for future clinical trials. T cells from peripheral blood (PBL) and tumor were analyzed for the expression of OX40, PD‐1 and CTLA‐4 in 29 patients undergoing surgery. These proteins were all expressed significantly higher in T‐cell subsets isolated from tumors compared with PBL of the same patient. OX40 expression was significantly greater in the TIL regulatory T‐cell (Treg) population relative to conventional CD4 and CD8 TIL or the Treg isolated from PBL. PD‐1 expression was increased in all T‐cell subsets relative to PBL. CTLA‐4 was also increased in all TIL subsets relative to blood, and similar to OX40, its highest level of expression was observed in the Treg TIL. The highest frequency of PD‐1, CTLA‐4 and OX40 triple‐positive cells were found in the Treg population isolated from the tumor. We analyzed both human papilloma virus‐positive and ‐negative patients and found similar levels and expression patterns of these two patient populations for all three proteins. These data suggest that there may be therapeutic advantages of targeting these pathways independently or in combination for patients with this disease.

Multiparametric immune profiling in HPV– oral squamous cell cancer

Evaluation of T lymphocyte frequency provides prognostic information for patients with oral squamous cell cancer (OSCC). However, the effect of simultaneously evaluating T cell frequency and assessing suppressive elements and defects in antigen-processing machinery (APM) has not been clarified. Simultaneous characterization of CD3+, CD8+, FoxP3+, CD163+, and PD-L1+ cells using multispectral imaging was performed on sections from 119 patients with HPV- OSCC. Expression of β2-microglobulin, MHC class I heavy chain, and large multifunctional peptidase 10 was quantified, and all data were correlated with patient outcome. We found that, consistent with previous reports, high numbers of CD8+ T cells at the invasive margin correlated significantly with prolonged overall survival (OS), while the number of FoxP3+ or PD-L1+ cells did not. Compiling the number of FoxP3+ or PD-L1+ cells within 30 μm of CD8+ T cells identified a significant association with a high number of suppressive elements close to CD8+ T cells and reduced OS. Integrating this information into a cumulative suppression index (CSI) increased correlation with OS. Incorporating tumor expression levels of APM components with CSI further improved prognostic power. This multiparametric immune profiling may be useful for stratifying patients with OSCC for clinical trials.

OX40 signaling in head and neck squamous cell carcinoma: Overcoming immunosuppression in the tumor microenvironment

OX40 is a member of the tumor necrosis factor (TNF) receptor family and a potent co-stimulatory pathway that when triggered can enhance T-cell memory, proliferation and anti-tumor activity in patients with metastatic cancer. Ongoing investigations at our institution have demonstrated that OX40 expressing T cells are found in abundance in the tumors of patients with advanced stage head and neck squamous cell carcinoma (HNSCC). This has led to the initiation of human clinical trials investigating OX40-directed therapy for patients with HNSCC in both the metastatic and curative setting. The purpose of this review is to explore what is known about OX40 signaling and discuss how this pathway potentially can be modulated to improve outcome for patients with HNSCC.

Cytoreductive surgery for head and neck squamous cell carcinoma in the new age of immunotherapy.

Cytoreductive surgery is an approach to cancer treatment that aims to reduce the number of cancer cells via resection of primary tumor or metastatic deposits, in an effort to minimize a potentially immunosuppressive tumor burden, palliate symptoms, and prevent complications. Furthermore, it provides a platform for investigation of biomarkers with the goal of optimizing immunotherapy to reverse the immunosuppressive tumor microenvironment and enhance adaptive immune responses. Ultimately, our group aims to exploit the concept that successful cancer therapy is dependent upon an effective immune response. Surgery will remain an integral part of head and neck squamous cell carcinoma (HNSCC) treatment in the future, even as checkpoint inhibitors, co-stimulatory molecules, vaccines, adoptive T cell therapy and other novel agents enter clinical routine. Cytoreductive resection may provide an effective platform for immunotherapy and biomarker directed interventions to improve outcomes for patients with HNSCC.

New Cancer Immunotherapy Agents in Development: a report from an associated program of the 31stAnnual Meeting of the Society for Immunotherapy of Cancer, 2016

This report is a summary of ‘New Cancer Immunotherapy Agents in Development’ program, which took place in association with the 31st Annual Meeting of the Society for Immunotherapy of Cancer (SITC), on November 9, 2016 in National Harbor, Maryland. Presenters gave brief overviews of emerging clinical and pre-clinical immune-based agents and combinations, before participating in an extended panel discussion with multidisciplinary leaders, including members of the FDA, leading academic institutions and industrial drug developers, to consider topics relevant to the future of cancer immunotherapy.

Developing an immunotherapy strategy for the effective treatment of patients with squamous cell carcinoma of the head and neck

Squamous cell carcinoma of the head and neck (HNSCC) arises in the oral cavity, oropharynx, larynx or hypopharynx, and is the 6th leading cause of cancer by incidence worldwide. Approximately 600,000 cases arise each year, and only 40-50% of these patients will survive for 5 years.7 HNSCC can express PD-L1 and suppressive factors that interfere with the differentiation and activation of dendritic cells and effector function of T cells. Similar to observations in other malignancies, CD8 effector T cell infiltration or transcriptional signature consistent with an ongoing T cell response is associated with prolonged survival. This suggests that HNSCC lacking a T cell infiltrate may benefit from immune interventions that induce and/or augment a tumor-specific immune response. To develop a strategy to address this problem we have created a HNSCC tumor bank that is cryopreserving enzymatically isolated viable cells from resected tumors (39 specimens). We are also attempting to develop primary cell lines (4 lines established) and are isolating tumor-infiltrating lymphocytes from these specimens. We are looking to compare immunohistochemical, flowcytometric and functional analyses of these specimens. Consistent with previous studies, results document that isolated TIL secrete IFN-γ when stimulated with their autologous tumor cells (n=2). Since a central aim of these studies is to develop a strategy to create therapeutic immunity in patients lacking T cell infiltrates, we plan to investigate which antigens are recognized and whether, antigens present in a novel DRibble vaccine, that expresses antigens common to HNSCC, are recognized by these TIL. This may provide a strategy to monitor anti-tumor immunity in these patients and possibly provide an antigen source for combination immunotherapy of patients with HNSCC.

Characterizing the immunoprofile and endogenous immune response to squamous cell carcinomas of the head and neck to guide development of effective immunotherapy strategies.

Squamous cell carcinoma of the head and neck (HNSCC) is the 6th leading cause of cancer by incidence worldwide with approximately 600,000 new cases per year. Unfortunately, only 40-50% of these patients will survive for 5 years. In order to study the immune response in patients with this disease we have developed a HNSCC tumor bank to compliment our Oral, Head and Neck Cancer Program. This tumor bank is cryopreserving enzymatically isolated viable cells from resected tumors (n = 128). We are also attempting to develop primary cell lines (10 lines established) and are isolating and assessing tumor-specific function of tumor-infiltrating lymphocytes (TIL) (n = 49). Since HNSCC can express immune inhibitory molecules and secrete suppressive factors, we are developing single stains and multi-spectral imaging protocols to assess the immune contexture of the tumor microenvironment by immunohistochemistry and immunoflouresence and are overlaying these studies with T cell functional activity and ultimately, with clinical outcome. Preliminary analyses suggest that tumor-specific T cells can be detected in 68% (N = 16) of patients evaluated. A goal of these studies is to identify strategies that will allow tailoring of therapy for patients with HNSCC. One component is to identify which inhibitors are present in a given tumor. Since not every tumor appears to contain TIL capable of recognizing autologous tumor, strategies to prime tumor-specific T cells represents another area of interest. DPV-001 is a microvesicle vaccine, DRibbles, that contains an average of at least 66 proteins that are overexpressed by HNSCC (TCGA provisional RNASeq n = 303 pts). The vaccine also contains multiple DAMPs and agonist activity for TLR 2, 3, 4, 7 and 9 packed into stable double membrane microvesicles that are targeted to CLEC9A+ APC. To increase potential activity against HPV positive cancers we have developed a mosaic construct encoding E6 and E7 peptides for a number of HPV strains and are evaluating both protein and gene-based HPV vaccine strategies. We are using the HNSCC TIL lines to evaluate DRibble vaccines and potential for adoptive immunotherapy trials. Support: NCI U43CA165048 and R44 CA121612 (TLH), OMS (HH, RBB), Steve and Cindy Harder, Robert W. and Elsie Franz, Wes and Nancy Lematta, Lynn and Jack Loacker, and The Chiles foundation (BAF).

OX40 and other immunoregulatory molecules are highly expressed on tumor infiltrating lymphocytes in oral, head and neck squamous cell carcinoma

OX40 is a potent co-stimulatory receptor on the surface of T lymphocytes. An OX40 agonist was recently tested in a Phase I clinical trial and was found to be well tolerated and enhanced both humoral and cellular immunity in patients with metastatic cancer. Both PD-1 and CTLA-4 blockade are showing therapeutic clinical activity in late stage cancer patients. Hence, we hypothesize that the immune suppressed tumor microenvironment that characterizes oral, head and neck squamous cell carcinoma (OHNSCC) can be overcome by strategies that favor antitumor inflammatory T cell responses and may be an ideal tumor site for immune modulation. This investigation aims to provide a better understanding of the expression of OX40, PD-1, CTLA-4 and CD103 in OHNSCC tumor infiltrating lymphocytes (TIL). Additionally we evaluated whether phenotypic differences existed in patients with HPV positive vs. negative status. Methods TIL and autologous blood were isolated from 29 patients undergoing surgery for OHNSCC. A sample of tissue was obtained from the resection specimen of the primary tumor and sent to the laboratory with autologous blood. Tumor was minced and subjected to digestive enzymes. Blood and tumor samples were separated over ficoll gradient to enrich for lymphocytes. Samples were frozen at -140°c and later thawed in batches for analysis. Proteins were then labeled with fluorescently conjugated antibodies and analyzed by flow cytometry. Results The percentage of FoxP3+CD25+CD4+ (Tregs) of CD4+ T cells is significantly higher in OHNSCC Tumor Infiltrating Lymphocytes (TIL) compared to blood (p < .0005), regardless of HPV status. OX40 expression is significantly higher in the TIL Treg population relative to blood Tregs (p < .0005), also independent of HPV status. PD1 expression is increased in the Tregs (p < .0005), conventional CD4 (p=.0066), and CD8 T cells (p < .0005), in TIL relative to blood. CTLA-4 expression is increased in TIL relative to blood in all subsets with the highest expression observed in the Treg population (.0056). CD103 expression is increased on CD8 T cells in TIL relative to blood (p < .0005). CD8s from HPV positive patients have higher percentage CD103 positive cells than CD8s from HPV negative patients (p=.0056). The highest percentages of PD-1, CTLA-4 and OX40 triple positive cells were found in the Treg population of TIL compared to blood (p < .0005). Due to increased expression of OX40, CTLA-4 and PD-1 in TIL of OHNSCC patients we hypothesize that future combination clinical trials that target these pathways will be therapeutically beneficial.

Erratum to ‘Cytoreductive surgery for head and neck squamous cell carcinoma in the new age of immunotherapy’ [Oral Oncol. 61 (2016) 166–176]

http://dx.doi.org/10.1016/j.oraloncology.2017.02.001 1368-8375/ 2017 Elsevier Ltd. All rights reserved. DOI of original article: http://dx.doi.org/10.1016/j.oraloncology.2016.08.020 ⇑ Corresponding author at: Providence Oral, Head and Neck Cancer Program and Clinic, Earle A. Chiles Research Institute at Providence Cancer Center, Providence Medical Center, 4805 NE Glisan St. Suite 2N35, Portland, OR 97213, United States. E-mail address: Richard.bell@providence.org (R.B. Bell).