Tumor-infiltrating lymphocyte treatment for anti-PD-1-resistant metastatic lung cancer: a phase 1 trial.

Adoptive cell therapy using tumor-infiltrating lymphocytes (TILs) has shown activity in melanoma, but has not been previously evaluated in metastatic non-small cell lung cancer. We conducted a single-arm open-label phase 1 trial ( NCT03215810 ) of TILs administered with nivolumab in 20 patients with advanced non-small cell lung cancer following initial progression on nivolumab monotherapy. The primary end point was safety and secondary end points included objective response rate, duration of response and T cell persistence. Autologous TILs were expanded ex vivo from minced tumors cultured with interleukin-2. Patients received cyclophosphamide and fludarabine lymphodepletion, TIL infusion and interleukin-2, followed by maintenance nivolumab. The end point of safety was met according to the prespecified criteria of ≤17% rate of severe toxicity (95% confidence interval, 3-29%). Of 13 evaluable patients, 3 had confirmed responses and 11 had reduction in tumor burden, with a median best change of 35%. Two patients achieved complete responses that were ongoing 1.5 years later. In exploratory analyses, we found T cells recognizing multiple types of cancer mutations were detected after TIL treatment and were enriched in responding patients. Neoantigen-reactive T cell clonotypes increased and persisted in peripheral blood after treatment. Cell therapy with autologous TILs is generally safe and clinically active and may constitute a new treatment strategy in metastatic lung cancer.

HDAC Inhibitors Enhance T-Cell Chemokine Expression and Augment Response to PD-1 Immunotherapy in Lung Adenocarcinoma.

PURPOSE: A significant limitation of checkpoint blockade immunotherapy is the relatively low response rate (e.g., ∼20% with PD-1 blockade in lung cancer). In this study, we tested whether strategies that increase T-cell infiltration to tumors can be efficacious in enhancing immunotherapy response. EXPERIMENTAL DESIGN: We performed an unbiased screen to identify FDA-approved oncology agents with an ability to enhance T-cell chemokine expression with the goal of identifying agents capable of augmenting immunotherapy response. Identified agents were tested in multiple lung tumor models as single agents and in combination with PD-1 blockade. Additional molecular and cellular analysis of tumors was used to define underlying mechanisms. RESULTS: We found that histone deacetylase (HDAC) inhibitors (HDACi) increased expression of multiple T-cell chemokines in cancer cells, macrophages, and T cells. Using the HDACi romidepsin in vivo, we observed increased chemokine expression, enhanced T-cell infiltration, and T-cell-dependent tumor regression. Importantly, romidepsin significantly enhanced the response to PD-1 blockade immunotherapy in multiple lung tumor models, including nearly complete rejection in two models. Combined romidepsin and PD-1 blockade also significantly enhanced activation of tumor-infiltrating T cells. CONCLUSIONS: These results provide evidence for a novel role of HDACs in modulating T-cell chemokine expression in multiple cell types. In addition, our findings indicate that pharmacologic induction of T-cell chemokine expression represents a conceptually novel approach for enhancing immunotherapy response. Finally, these results suggest that combination of HDAC inhibitors with PD-1 blockade represents a promising strategy for lung cancer treatment. Clin Cancer Res; 22(16); 4119-32. ©2016 AACR.

Effects of environmental stressors on lymphocyte proliferation in Florida manatees, Trichechus manatus latirostris.

The health of many Florida manatees (Trichechus manatus latirostris) is adversely affected each year by exposure to cold weather or harmful algal blooms (red tide; Karenia brevis). Exposures can be sublethal, resulting in stressed animals that are rescued and taken to authorized facilities for rehabilitation, or lethal if exposures are prolonged or unusually severe. To investigate whether sublethal environmental exposures can impair immune function in manatees, rendering animals vulnerable to disease or death, mitogen-induced proliferation was assessed in lymphocytes from manatees exposed to cold temperatures (N=20) or red tide (N=19) in the wild, and compared to lymphocyte responses from healthy free-ranging manatees (N=32). All animals sampled for this study were adults. Lymphocytes were stimulated in vitro with either concanavalin A (ConA) or phytohemagglutinin (PHA) and proliferation was assessed after 96 h using incorporation of the thymidine analog, bromodeoxyuridine (BrdU), into newly synthesized DNA. Proliferation of lymphocytes from manatees rescued from exposure to red tide or cold-stress was approximately one-third that of lymphocytes from healthy free-ranging manatees. To examine the direct effects of red tide toxins on lymphocyte function, mitogen-induced proliferation was assessed following co-culture of lymphocytes with K. brevis toxin extracts. Stimulation indices decreased with increasing toxin concentration, with a significant decrease in proliferation occurring in the presence of 400 ng red tide toxins/ml. When lymphocytes from cold-stressed manatees were co-cultured with red tide toxin extracts, proliferative responses were reduced even further, suggesting multiple stressors may have synergistic effects on immune function in manatees.

Combination of external beam radiotherapy (EBRT) with intratumoral injection of dendritic cells as neo-adjuvant treatment of high-risk soft tissue sarcoma patients.

PURPOSE: The goal of this study was to determine the effect of combination of intratumoral administration of dendritic cells (DC) and fractionated external beam radiation (EBRT) on tumor-specific immune responses in patients with soft-tissue sarcoma (STS). METHODS AND MATERIAL: Seventeen patients with large (>5 cm) high-grade STS were enrolled in the study. They were treated in the neoadjuvant setting with 5,040 cGy of EBRT, split into 28 fractions and delivered 5 days per week, combined with intratumoral injection of 10(7) DCs followed by complete resection. DCs were injected on the second, third, and fourth Friday of the treatment cycle. Clinical evaluation and immunological assessments were performed. RESULTS: The treatment was well tolerated. No patient had tumor-specific immune responses before combined EBRT/DC therapy; 9 patients (52.9%) developed tumor-specific immune responses, which lasted from 11 to 42 weeks. Twelve of 17 patients (70.6%) were progression free after 1 year. Treatment caused a dramatic accumulation of T cells in the tumor. The presence of CD4(+) T cells in the tumor positively correlated with tumor-specific immune responses that developed following combined therapy. Accumulation of myeloid-derived suppressor cells but not regulatory T cells negatively correlated with the development of tumor-specific immune responses. Experiments with (111)In labeled DCs demonstrated that these antigen presenting cells need at least 48 h to start migrating from tumor site. CONCLUSIONS: Combination of intratumoral DC administration with EBRT was safe and resulted in induction of antitumor immune responses. This suggests that this therapy is promising and needs further testing in clinical trials design to assess clinical efficacy.

Phase II trial of B7-1 (CD-86) transduced, cultured autologous tumor cell vaccine plus subcutaneous interleukin-2 for treatment of stage IV renal cell carcinoma.

We report a single center phase II trial of sequential vaccination followed with vaccine plus interleukin-2 (IL-2). Vaccination consisted of autologous cells cultured from primary tumor or resected metastasis, transduced to express B7.1 surface molecule and then irradiated. The vaccine would hypothetically costimulate tumor-reactive T cells before IL-2 exposure. Treatment plan was 3 subcutaneous vaccine injections at 4-week intervals and subcutaneous IL-2 treatment for 6 weeks starting at week 7. Sixty-six patients enrolled, of whom 39 received at least 1 vaccine; most observed toxicity was attributable to IL-2 not vaccine; best responses were 3% pathologic complete response, 5% partial response, 64% stable disease, and 28% disease progression. Median survival was 21.8 months (95% confidence interval 17.8 to 29.6). Significant postvaccination increases in IFN-gamma responses to autologous tumor were observed in 2/26 cases. Eighty-one percent of posttreatment subdermal delayed-type hypersensitivity tests (using nontransduced, irradiated autologous tumor cells) had biopsies demonstrating injection site lymphocytic infiltration. Post hoc comparison of the median survival of subjects whose biopsies had lymphocytic infiltration appears longer than in the 19% noninfiltrated (28.4 vs. 17.8 mo, P=0.045, two-sided log-rank test). The single arm design precludes conclusive comparison of objective response rates (not different here) or median survival (longer here) versus those of historical series using similar IL-2 schedules alone. Better outcomes could be logically associated to vaccine response (detectable lymphocytic infiltrates) or to random events that a single arm study design cannot address. This vaccine approach may merit further clinical development.

Nitric oxide production by nurse shark (Ginglymostoma cirratum) and clearnose skate (Raja eglanteria) peripheral blood leucocytes.

Reactive nitrogen intermediates, such as nitric oxide (NO), are important immunomodulators in vertebrate immune systems, but have yet to be identified as mediators of host defence in any member of class Chondrichthyes, the cartilaginous fishes. In the present study, production of NO by nurse shark (Ginglymostoma cirratum) peripheral blood leucocytes (PBL) stimulated with bacterial cell wall lipopolysaccharide (LPS) was investigated. PBL were cultured for 24 to 96 h following stimulation with LPS at concentrations ranging from 0 to 25 microg ml(-1), in both serum-supplemented and serum-free culture conditions. Production of NO was measured indirectly using the Griess reaction, with maximal NO production occurring after 72 h using 10% FBS and 10 microg LPS ml(-1). Application of these culture conditions to PBL from another cartilaginous fish (clearnose skate, Raja eglanteria) resulted in a similar NO response. Addition of a specific inhibitor of inducible nitric oxide synthase (iNOS), L-N(6)-(1-iminoethyl)lysine (L-NIL), resulted in a significant decrease in the production of NO by PBL from both species.

Elasmobranch immune cells as a source of novel tumor cell inhibitors: Implications for public health.

SYNOPSIS: Reports that elasmobranchs (sharks, skates, and rays) may have a low incidence of disease have stimulated interest in understanding the role of their immune system in this apparent resistance. Although research in this area may potentially translate into applications for human health, a basic understanding of the elasmobranch immune system components and how they function is essential. As in higher vertebrates, elasmobranch fishes possess thymus and spleen, but in the absence of bone marrow and lymph nodes, these fish have evolved unique lymphomyeloid tissues, namely epigonal and Leydig organs. As conditions for short-term culture of elasmobranch immune cells have become better understood, the opportunity to examine functional activity of cytokine-like factors derived from conditioned culture medium has resulted in the identification of growth inhibitory activity against a variety of tumor cell lines. Specifically, the medium enriched by short term culture of bonnethead shark (Sphyrna tiburo) epigonal cells (epigonal conditioned medium, ECM) has been shown to inhibit the growth of mammalian tumor cell lines, including fibrosarcoma (WEHI-164), melanoma (A375.S2), B-cell lymphoma (Daudi), T-cell leukemia (Jurkat), pancreatic cancer (PANC-1), ovarian cancer (NIH:OVCAR-3), and three breast carcinoma cell lines (MCF7, HCC38, Hs578T). Of the cell lines tested, WEHI-164, A375.S2, Daudi, and Jurkat cells were among the most sensitive to growth inhibitory activity of ECM whereas PANC-1 and NIH:OVCAR-3 cells were among the least sensitive. In addition, ECM demonstrated preferential growth inhibition of malignant cells in assays against two different malignant/non-malignant cell line pairs (HCC38/HCC38 BL and Hs 578T/Hs 578Bst). Separation of protein components of ECM using SDS-PAGE resulted in a very reproducible pattern of three major bands corresponding to molecular sizes of approximately 40-42 kD, 24 kD, and 17 kD. Activity is lost after heating at 75 degrees C for 30 min, and can be diminished by treatment with proteinase K and protease. Activity is not affected by treating with trypsin, DNase I or RNase A.