Sanja Stevanovic

Complete Regression of Metastatic Cervical Cancer After Treatment With Human Papillomavirus–Targeted Tumor-Infiltrating T Cells

PURPOSE Metastatic cervical cancer is a prototypical chemotherapy-refractory epithelial malignancy for which better treatments are needed. Adoptive T-cell therapy (ACT) is emerging as a promising cancer treatment, but its study in epithelial malignancies has been limited. This study was conducted to determine if ACT could mediate regression of metastatic cervical cancer. PATIENTS AND METHODS Patients enrolled onto this protocol were diagnosed with metastatic cervical cancer and had previously received platinum-based chemotherapy or chemoradiotherapy. Patients were treated with a single infusion of tumor-infiltrating T cells selected when possible for human papillomavirus (HPV) E6 and E7 reactivity (HPV-TILs). Cell infusion was preceded by lymphocyte-depleting chemotherapy and was followed by administration of aldesleukin. RESULTS Three of nine patients experienced objective tumor responses (two complete responses and one partial response). The two complete responses were ongoing 22 and 15 months after treatment, respectively. One partial response was 3 months in duration. The HPV reactivity of T cells in the infusion product (as measured by interferon gamma production, enzyme-linked immunospot, and CD137 upregulation assays) correlated positively with clinical response (P = .0238 for all three assays). In addition, the frequency of HPV-reactive T cells in peripheral blood 1 month after treatment was positively associated with clinical response (P = .0238). CONCLUSION Durable, complete regression of metastatic cervical cancer can occur after a single infusion of HPV-TILs. Exploratory studies suggest a correlation between HPV reactivity of the infusion product and clinical response. Continued investigation of this therapy is warranted.

Landscape of immunogenic tumor antigens in successful immunotherapy of virally induced epithelial cancer

Targeting nonviral antigens in viral-driven cancer Adoptive cell transfer harnesses a patients own T cells to destroy cancer. The strategy can successfully treat epithelial tumors driven by human papillomavirus (HPV), but it remains unclear why only some patients respond. Stevanović et al. examined the antitumor T cell response associated with HPV+ cervical cancers that underwent complete regression. Unexpectedly, reactive T cells were not directed against virally associated antigens, but rather against cancer germline antigens or neoantigens not previously recognized by the immune system. These findings counter the widely held belief that T cell responses against viral antigens are responsible for therapeutic effects in HPV-driven cancers. Science, this issue p. 200 Reactive T cells directed against nonviral antigens lead to regression of human papilloma virus–positive cervical cancer. Immunotherapy has clinical activity in certain virally associated cancers. However, the tumor antigens targeted in successful treatments remain poorly defined. We used a personalized immunogenomic approach to elucidate the global landscape of antitumor T cell responses in complete regression of human papillomavirus–associated metastatic cervical cancer after tumor-infiltrating adoptive T cell therapy. Remarkably, immunodominant T cell reactivities were directed against mutated neoantigens or a cancer germline antigen, rather than canonical viral antigens. T cells targeting viral tumor antigens did not display preferential in vivo expansion. Both viral and nonviral tumor antigen–specific T cells resided predominantly in the programmed cell death 1 (PD-1)–expressing T cell compartment, which suggests that PD-1 blockade may unleash diverse antitumor T cell reactivities. These findings suggest a new paradigm of targeting nonviral antigens in immunotherapy of virally associated cancers.

Targeting of HPV-16+ Epithelial Cancer Cells by TCR Gene Engineered T Cells Directed against E6

Purpose: The E6 and E7 oncoproteins of HPV-associated epithelial cancers are in principle ideal immunotherapeutic targets, but evidence that T cells specific for these antigens can recognize and kill HPV+ tumor cells is limited. We sought to determine whether TCR gene engineered T cells directed against an HPV oncoprotein can successfully target HPV+ tumor cells. Experimental Design: T-cell responses against the HPV-16 oncoproteins were investigated in a patient with an ongoing 22-month disease-free interval after her second resection of distant metastatic anal cancer. T cells genetically engineered to express an oncoprotein-specific TCR from this patients tumor-infiltrating T cells were tested for specific reactivity against HPV+ epithelial tumor cells. Results: We identified, from an excised metastatic anal cancer tumor, T cells that recognized an HLA-A*02:01–restricted epitope of HPV-16 E6. The frequency of the dominant T-cell clonotype from these cells was approximately 400-fold greater in the patients tumor than in her peripheral blood. T cells genetically engineered to express the TCR from this clonotype displayed high avidity for an HLA-A*02:01–restricted epitope of HPV-16, and they showed specific recognition and killing of HPV-16+ cervical, and head and neck cancer cell lines. Conclusions: These findings demonstrate that HPV-16+ tumors can be targeted by E6-specific TCR gene engineered T cells, and they provide the foundation for a novel cellular therapy directed against HPV-16+ malignancies, including cervical, oropharyngeal, anal, vulvar, vaginal, and penile cancers. Clin Cancer Res; 21(19); 4431–9. ©2015 AACR.

HPV-targeted tumor-infiltrating lymphocytes for cervical cancer.

LBA3008 Background: Adoptive T-cell therapy (ACT) is a promising cancer treatment modality with potentially broad application. It is not known if ACT can mediate regression of carcinomas, the most common solid tumors in humans. We studied carcinoma of the uterine cervix, a virally induced malignancy that constitutively expresses the HPV E6 and E7 oncoproteins, as a model cancer to test if ACT can mediate regression of an epithelial malignancy. METHODS We initiated a clinical trial to treat metastatic HPV+ cancers with tumor-infiltrating lymphocytes (TIL) selected for HPV E6- and E7-reactivity (HPV-TIL). Patients from the cervical cancer cohort are reported here. HPV-TIL infusion was preceded b y non-myeloablative conditioning and followed by high-dose bolus aldesleukin. HPV-reactivity was assessed by ELISPOT, IFN-gamma production, and CD137 expression assays. RESULTS Nine patients were treated on the study. They received a median of 81 x 109 T cells (range 33 to 159 x 109) as a single infusion. The infused cells possessed reactivity against high-risk HPV E6 and/or E7 in 6/8 patients. The two patients with no HPV reactivity did not respond to treatment. 3/6 patients with HPV reactivity demonstrated objective tumor responses by RECIST (1 PR and 2 CR). One patient had a 39% best response. Two patients with widespread metastases had complete tumor responses that are ongoing 18 and 11 months after treatment. One patient with a complete response had a chemotherapy-refractory HPV-16+ squamous cell carcinoma and the other a chemoradiation-refractory HPV-18+ adenocarcinoma. Both patients demonstrated prolonged repopulation with HPV-reactive T cells following treatment. Increased frequencies of HPV-specific T cells were detectable after 13 months in one patient and 6 months in the other. Two patients with HPV-reactive TIL that did not respond to treatment did not display repopulation with HPV-reactive T cells. CONCLUSIONS HPV-TIL can mediate durable, complete regression of metastatic cervical cancer. Continued investigation of HPV-TIL for cervical cancer, and possibly other HPV+ malignancies, is warranted. Cellular therapy can mediate complete regression of an epithelial malignancy. CLINICAL TRIAL INFORMATION NCT01585428.

Adoptive transfer of tumor infiltrating lymphocytes for metastatic cervical cancer

Adoptive T-cell therapies for cancer can induce tumor responses in patients with metastatic melanoma, synovial sarcoma, and B-cell malignancies. However, no cellular therapy has demonstrated activity in a common epithelial tumor. Adoptive transfer of tumor infiltrating lymphocytes (TIL) has high response rates and can induce complete and durable tumor regression in metastatic melanoma. We sought to determine the objective tumor response rate of TIL therapy for human papillomavirus (HPV)-associated malignancies. These common epithelial cancers occur at varied sites but universally express the immunogenic E6 and E7 viral oncoproteins making them rational targets for T cell-based therapeutic approaches. Herein we report the results of treatment of the first eight subjects (seven evaluable) from the cohort of patients with cervical cancer (which is necessarily associated with high-risk HPV infection) treated with TIL therapy. Tumors were HPV genotyped and TIL were generated from individual tumor fragment cultures then tested for reactivity against autologous dendritic cells loaded with pools of overlapping peptides spanning type-specific HPV E6 or E7 proteins. Cultures were selected for rapid expansion and administration to patients based on oncoprotein reactivity, T-cell growth rate, and CD8+ T cell frequency. Patients received non-myeloablative lymphoconditioning chemotherapy before cell infusion and high-dose bolus IL-2 after cell infusion. TIL from 6/8 patients displayed reactivity against E6 or E7. Objective tumor responses by RECIST criteria were observed in 3/7 evaluable patients; two have complete and ongoing regression of measurable disease at three and nine months after treatment. Adverse events were the expected combined toxicities of the preparative chemotherapy regimen and interleukin-2, and were consistent with those of TIL therapy for metastatic melanoma. No autoimmunity was observed. These early clinical trial results indicate that tumor responses can occur following administration of TIL for metastatic cervical cancer.

Engineered T cells targeting E7 mediate regression of human papillomavirus cancers in a murine model

T cell receptor (TCR) T cell therapy is a promising cancer treatment modality. However, its successful development for epithelial cancers may depend on the identification of high-avidity TCRs directed against tumor-restricted target antigens. The human papillomavirus (HPV) E7 antigen is an attractive therapeutic target that is constitutively expressed by HPV+ cancers but not by healthy tissues. It is unknown if genetically engineered TCR T cells that target E7 can mediate regression of HPV+ cancers. We identified an HPV-16 E7-specific, HLA-A*02:01-restricted TCR from a uterine cervix biopsy from a woman with cervical intraepithelial neoplasia. This TCR demonstrated high functional avidity, with CD8 coreceptor-independent tumor targeting. Human T cells transduced to express the TCR specifically recognized and killed HPV-16+ cervical and oropharyngeal cancer cell lines and mediated regression of established HPV-16+ human cervical cancer tumors in a mouse model. These findings support the therapeutic potential of this approach and established the basis for an E7 TCR gene therapy clinical trial in patients with metastatic HPV+ cancers (NCT02858310).

Human Papillomavirus T-Cell Cross-reactivity in Cervical Cancer: Implications for Immunotherapy Clinical Trial Design

Key Points Question Does the cross-reactivity of T cells against the human papillomavirus (HPV) oncoproteins in HPV-positive cancers support current immunotherapeutic vaccine clinical trial designs in which the HPV type of the tumor is not matched with the HPV type of the vaccine? Findings In an analysis of 16 samples, HPV-reactive tumor-infiltrating lymphocytes from patients with HPV-positive cancers displayed HPV-16/HPV-18 oncoprotein cross-reactivity in 1 of 16 samples. None of the 10 HPV-reactive T-cell receptors from the researchers’ library exhibited HPV-16/HPV-18 oncoprotein cross-reactivity. Meaning The low frequency of HPV-16/HPV-18 T-cell cross-reactivity supports clinical trial designs that match the HPV type of therapeutic vaccines to that of patient tumors.

Adoptively transferred tumor-infiltrating T cells target somatic cancer mutations in a human papillomavirus+ cancer patient with complete tumor regression

Meeting abstracts Adoptive transfer of tumor-infiltrating lymphocytes (TIL) can mediate complete regression of metastatic cervical cancer, but the immunological landscape of the anti-tumor T cell responses in these patients is not fully understood. Reactivity against the human papillomavirus (HPV)-