Phenotypic signatures of circulating neoantigen-reactive CD8+ T cells in patients with metastatic cancers.

Circulating T cells from peripheral blood (PBL) can provide a rich and noninvasive source for antitumor T cells. By single-cell transcriptomic profiling of 36 neoantigen-specific T cell clones from 6 metastatic cancer patients, we report the transcriptional and cell surface signatures of antitumor PBL-derived CD8+ T cells (NeoTCRPBL). Comparison of tumor-infiltrating lymphocyte (TIL)- and PBL-neoantigen-specific T cells revealed that NeoTCRPBL T cells are low in frequency and display less-dysfunctional memory phenotypes relative to their TIL counterparts. Analysis of 100 antitumor TCR clonotypes indicates that most NeoTCRPBL populations target the same neoantigens as TILs. However, NeoTCRPBL TCR repertoire is only partially shared with TIL. Prediction and testing of NeoTCRPBL signature-derived TCRs from PBL of 6 prospective patients demonstrate high enrichment of clonotypes targeting tumor mutations, a viral oncogene, and patient-derived tumor. Thus, the NeoTCRPBL signature provides an alternative source for identifying antitumor T cells from PBL of cancer patients, enabling immune monitoring and immunotherapies.

Neoantigen Identification and Response to Adoptive Cell Transfer in Anti-PD-1 Naïve and Experienced Patients with Metastatic Melanoma.

PURPOSE: Immune checkpoint blockade (ICB) agents and adoptive cell transfer (ACT) of tumor-infiltrating lymphocytes (TIL) are prominent immunotherapies used for the treatment of advanced melanoma. Both therapies rely on activation of lymphocytes that target shared tumor antigens or neoantigens. Recent analysis of patients with metastatic melanoma who underwent treatment with TIL ACT at the NCI demonstrated decreased responses in patients previously treated with anti-PD-1 agents. We aimed to find a basis for the difference in response rates between anti-PD-1 naïve and experienced patients. PATIENTS AND METHODS: We examined the tumor mutational burden (TMB) of resected tumors and the repertoire of neoantigens targeted by autologous TIL in a cohort of 112 anti-PD-1 naïve and 69 anti-PD-1 experienced patients. RESULTS: Anti-PD-1 naïve patients were found to possess tumors with higher TMBs (352.0 vs. 213.5, P = 0.005) and received TIL reactive with more neoantigens (2 vs. 1, P = 0.003) compared with anti-PD-1 experienced patients. Among patients treated with TIL ACT, TMB and number of neoantigens identified were higher in ACT responders than ACT nonresponders in both anti-PD-1 naïve and experienced patients. Among patients with comparable TMBs and predicted neoantigen loads, treatment products administered to anti-PD-1 naïve patients were more likely to contain T cells reactive against neoantigens than treatment products for anti-PD-1 experienced patients (2.5 vs. 1, P = 0.02). CONCLUSIONS: These results indicate that decreases in TMB and targeted neoantigens partially account for the difference in response to ACT and that additional factors likely influence responses in these patients. See related commentary by Blass and Ott, p. 2980.

Molecular signatures of antitumor neoantigen-reactive T cells from metastatic human cancers.

The accurate identification of antitumor T cell receptors (TCRs) represents a major challenge for the engineering of cell-based cancer immunotherapies. By mapping 55 neoantigen-specific TCR clonotypes (NeoTCRs) from 10 metastatic human tumors to their single-cell transcriptomes, we identified signatures of CD8+ and CD4+ neoantigen-reactive tumor-infiltrating lymphocytes (TILs). Neoantigen-specific TILs exhibited tumor-specific expansion with dysfunctional phenotypes, distinct from blood-emigrant bystanders and regulatory TILs. Prospective prediction and testing of 73 NeoTCR signature-derived clonotypes demonstrated that half of the tested TCRs recognized tumor antigens or autologous tumors. NeoTCR signatures identified TCRs that target driver neoantigens and nonmutated viral or tumor-associated antigens, suggesting a common metastatic TIL exhaustion program. NeoTCR signatures delineate the landscape of TILs across metastatic tumors, enabling successful TCR prediction based purely on TIL transcriptomic states for use in cancer immunotherapy.

Impact of Prior Treatment on the Efficacy of Adoptive Transfer of Tumor-Infiltrating Lymphocytes in Patients with Metastatic Melanoma.

PURPOSE: Adoptive cell transfer (ACT) of autologous tumor-infiltrating lymphocytes (TIL) can mediate durable responses in patients with metastatic melanoma. This retrospective analysis provides long-term follow-up and describes the effect of prior therapy on outcomes after ACT-TIL. PATIENTS AND METHODS: Patients with metastatic melanoma underwent surgical resection of a tumor for generation of TILs and were treated with a lymphodepleting preparative regimen followed by adoptive transfer of TILs and intravenous IL2. Clinical characteristics of enrolled patients and treatment characteristics of TIL infusion products over two decades of ACT were analyzed to identify predictors of objective response. RESULTS: Adoptive transfer of TILs mediated an objective response rate of 56% (108/192) and median melanoma-specific survival of 28.5 months in patients naïve to anti-programmed cell death-1 (PD-1) therapy compared with 24% (8/34) and 11.6 months in patients refractory to anti-PD-1 (aPD-1). Among patients with BRAF V600E/K-mutated disease, prior treatment with targeted molecular therapy was also associated with a decreased response rate (21% vs. 60%) and decreased survival (9.3 vs. 50.7 months) when compared with those patients naïve to targeted therapy. With a median potential follow-up of 89 months, 46 of 48 complete responders in the aPD-1-naïve cohort have ongoing responses after a single treatment and 10-year melanoma-specific survival of 96%. CONCLUSIONS: Patients previously treated with PD-1 or MAPK inhibition are significantly less likely to develop durable objective responses to ACT-TIL. While ACT-TIL is currently being investigated for treatment-refractory patients, it should also be considered as an initial treatment option for eligible patients with metastatic melanoma. See related commentary by Sznol, p. 5156.

Identification and Validation of T-cell Receptors Targeting RAS Hotspot Mutations in Human Cancers for Use in Cell-based Immunotherapy.

PURPOSE: Immunotherapies mediate the regression of human tumors through recognition of tumor antigens by immune cells that trigger an immune response. Mutations in the RAS oncogenes occur in about 30% of all patients with cancer. These mutations play an important role in both tumor establishment and survival and are commonly found in hotspots. Discovering T-cell receptors (TCR) that recognize shared mutated RAS antigens presented on MHC class I and class II molecules are thus promising reagents for "off-the-shelf" adoptive cell therapies (ACT) following insertion of the TCRs into lymphocytes. EXPERIMENTAL DESIGN: In this ongoing work, we screened for RAS antigen recognition in tumor-infiltrating lymphocytes (TIL) or by in vitro stimulation of peripheral blood lymphocytes (PBL). TCRs recognizing mutated RAS were identified from the reactive T cells. The TCRs were then reconstructed and virally transduced into PBLs and tested. RESULTS: Here, we detect and report multiple novel TCR sequences that recognize nonsynonymous mutant RAS hotspot mutations with high avidity and specificity and identify the specific class-I and -II MHC restriction elements involved in the recognition of mutant RAS. CONCLUSIONS: The TCR library directed against RAS hotspot mutations described here recognize RAS mutations found in about 45% of the Caucasian population and about 60% of the Asian population and represent promising reagents for "off-the-shelf" ACTs.

Contralateral Suppression Index Does Not Predict Clinical Cure in Patients Undergoing Surgery for Primary Aldosteronism.

BACKGROUND: Adrenal venous sampling (AVS) is recommended before adrenalectomy for patients with primary aldosteronism (PA) over 35 years old. The literature examining contralateral suppression (CoS) on AVS in predicting surgical outcomes is conflicting. We examined the presence of CoS in patients who underwent adrenalectomy while adjusting for clinical and biochemical factors associated with a clinical cure of hypertension (ccHTN). METHODS: We performed a retrospective review of patients with successful AVS who underwent unilateral adrenalectomy for PA at a quaternary referral center. Patients were excluded if they had overt cortisol co-secretion, or inadequate follow-up. We first evaluated the aldosterone resolution score (ARS) in predicting ccHTN in our cohort. Next, the receiver-operator characteristic analysis (ROC) was used to determine the optimal contralateral suppression index (CSI) cutoff to define CoS. We performed univariable and multivariable analyses of factors associated with ccHTN. The primary outcome was ccHTN defined as blood pressure less than 140/90 mmHg, and off blood pressure medications. RESULTS: Of the 102 patients on bivariable analysis, age, sex, duration of HTN, number of medications, preoperative systolic blood pressure, and creatinine level were associated with ccHTN. ROC analysis of ARS had an AUC of 0.850 (p < 0.001). On multivariable analysis, only ARS remained associated with ccHTN (OR 3.40, 95% CI 1.20-9.61, p = 0.021). CSI was not significantly associated with ccHTN on ROC, bivariable, or multivariable analyses. CONCLUSION: The presence of CoS was not useful in predicting ccHTN following unilateral adrenalectomy for PA in our cohort. After adjusting for clinical and biochemical factors, ARS remains a useful predictor for ccHTN.

Evaluation of Factors Associated With Successful Matriculation to Colon and Rectal Surgery Fellowship.

BACKGROUND: As an increasing number of general surgery residents apply for fellowship positions, it is important to identify factors associated with successful matriculation. For applicants to colon and rectal surgery, there are currently no objective data available to distinguish which applicant attributes lead to successful matriculation. OBJECTIVE: The purpose of this study was to identify objective factors that differentiate colon and rectal surgery fellowship applicants who successfully matriculate with those who apply but do not matriculate. DESIGN: This was a retrospective analysis of colon and rectal surgery applicant characteristics. SETTINGS: Deidentified applicant data provided by the Association of American Medical Colleges from 2015 to 2017 were included. MAIN OUTCOME MEASURES: Applicant demographics, medical school and residency factors, number of program applications, number of publications, and journal impact factors were analyzed to determine associations with successful matriculation. RESULTS: Most applicants (n = 371) and subsequent matriculants (n = 248) were white (61%, 62%), male (65%, 63%), US citizens (80%, 88%) who graduated from US allopathic medical schools (66%, 75%). Statistically significant associations included graduation from US allopathic medical schools (p < 0.0001), US citizenship (p < 0.0001), and number of program applications (p = 0.0004). Other factors analyzed included American Osteopathic Association membership (p = 0.57), university-based residency (p = 0.51), and residency association with a colon and rectal surgery training program (p = 0.89). Number of publications and journal impact factors were not statistically different between cohorts (p = 0.067, p = 0.150). LIMITATIONS: American Board of Surgery In-Training Examination scores, rank list, and subjective characteristics, such as strength of interview and letters of recommendation, were not available using our data source. CONCLUSIONS: Successful matriculation to a colon and rectal surgery fellowship program was found to be associated with US citizenship, graduation from a US allopathic medical school, and greater number of program applications. The remaining objective metrics analyzed were not associated with successful matriculation. Subjective and objective factors that were unable to be measured by this study are likely to play a determining role. See Video Abstract at http://links.lww.com/DCR/B415. EVALUACIN DE FACTORES VINCULADOS EN LA INMATRICULACIN EXITOSA PARA BECAS DE CIRUGA COLORRECTAL: ANTECEDENTES:A medida que un número cada vez mayor de residentes de Cirugía General solicitan una beca, es importante identificar los factores vinculados con una inmatriculación exitosa. Para los candidatos a una beca en Cirugía Colorrectal, hoy en día no existen datos objetivos disponibles para distinguir qué atributos del solicitante conducen a una inmatriculación exitosa.OBJETIVO:Identificar objetivamente los factores que diferencian un candidato a una beca en Cirugía Colorrectal que se inmatricula con éxito de aquel que aplica pero no llega a inmatricularse.DISEÑO:Análisis retrospectivo de las características de los solicitantes de beca para Cirugía Colorrecatl.AJUSTES:Datos de los solicitantes no identificados, proporcionados por la Asociación de Colegios Médicos Estadounidenses de 2015 a 2017.PRINCIPALES MEDIDAS DE RESULTADO:Se analizaron los factores demográficos del solicitante, las facultades de medicina y los factores de la residencia, el número de solicitudes de programas, el número y el factor de impacto de las publicaciones realizadas para determinar la asociación con una inmatriculación exitosa.RESULTADOS:La mayoría de los solicitantes (n = 371) que posteriormente fueron inmatriculados exitosamente (n = 248) eran blancos (61%, 62%, respectivamente), hombres (65%, 63%), ciudadanos estadounidenses (80%, 88%) que se graduaron de Facultades de medicina alopática en los EE. UU. (66%, 75%). Las asociaciones estadísticamente significativas incluyeron la graduación de las escuelas de medicina alopática de los EE. UU. (P <0,0001), la ciudadanía de los EE. UU. (P <0,0001) y el número de solicitudes de programas (p = 0,0004). Otros factores analizados incluyeron: membresía AOA (p = 0,57), la residencia universitaria (p = 0,51) y asociación de la residencia con un programa de formación en Cirugía Colorrectal (p = 0,89). El número de publicaciones y los factores de impacto de las revistas no fueron estadísticamente diferentes entre las cohortes (p = 0,067, p = 0,15, respectivamente).LIMITACIONES:El Score ABSITE, la posición en lista de clasificación y las características subjetivas como el de una buena entrevista y las cartas de recomendación no se encontraban disponibles en la fuente de datos.CONCLUSIONES:Se encontró que la inmatriculación exitosa a un programa de becas de Cirugía Colorreectal estaba asociada con la ciudadanía estadounidense, la graduación en una Facultad de medicina alopática en los EE. UU, y al mayor número de solicitudes de programas. El analisis de las medidas objetivas restantes no se asociaron con una inmatriculación exitosa. Es probable que los factores subjetivos y objetivos que no pudieron ser medidos por este estudio jueguen un papel determinante. Consulte Video Resumen en http://links.lww.com/DCR/B415. (Traducción-Dr Xavier Delgadillo).

Stem-like CD8 T cells mediate response of adoptive cell immunotherapy against human cancer.

Adoptive T cell therapy (ACT) using ex vivo-expanded autologous tumor-infiltrating lymphocytes (TILs) can mediate complete regression of certain human cancers. The impact of TIL phenotypes on clinical success of TIL-ACT is currently unclear. Using high-dimensional analysis of human ACT products, we identified a memory-progenitor CD39-negative stem-like phenotype (CD39-CD69-) associated with complete cancer regression and TIL persistence and a terminally differentiated CD39-positive state (CD39+CD69+) associated with poor TIL persistence. Most antitumor neoantigen-reactive TILs were found in the differentiated CD39+ state. However, ACT responders retained a pool of CD39- stem-like neoantigen-specific TILs that was lacking in ACT nonresponders. Tumor-reactive stem-like TILs were capable of self-renewal, expansion, persistence, and superior antitumor response in vivo. These data suggest that TIL subsets mediating ACT response are distinct from TIL subsets enriched for antitumor reactivity.

Antigen Experienced T Cells from Peripheral Blood Recognize p53 Neoantigens.

PURPOSE: The purpose of this study was to evaluate antigen experienced T cells in peripheral blood lymphocytes (PBL) for responses to p53 neoantigens. EXPERIMENTAL DESIGN: PBLs from patients with a mutated TP53 tumor were sorted for antigen-experienced T cells and in vitro stimulation (IVS) was performed with p53 neoantigens. The IVS cultures were stimulated with antigen-presenting cells expressing p53 neoantigens, enriched for 41BB/OX40 and grown with rapid expansion protocol. RESULTS: T-cell responses were not observed in the PBLs of 4 patients who did not have tumor-infiltrating lymphocyte (TIL) responses to mutated TP53. In contrast, 5 patients with TIL responses to mutated TP53 also had similar T-cell responses in their PBLs, indicating that the PBLs and TILs were congruent in p53 neoantigen reactivity. CD4+ and CD8+ T cells were specific for p53R175H, p53Y220C, or p53R248W neoantigens, including a 78% reactive T-cell culture against p53R175H and HLA-A*02:01. Tracking TCRB clonotypes (clonality, top ranked, and TP53 mutation-specific) supported the enrichment of p53 neoantigen-reactive T cells from PBLs. The same T-cell receptor (TCR) from the TIL was found in the IVS cultures in three cases and multiple unique TCRs were found in another patient. TP53 mutation-specific T cells also recognized tumor cell lines bearing the appropriate human leukocyte antigen restriction element and TP53 mutation, indicating these T cells could recognize processed and presented p53 neoantigens. CONCLUSIONS: PBL was a noninvasive source of T cells targeting TP53 mutations for cell therapy and can provide a window into intratumoral p53 neoantigen immune responses.See related commentary by Olivera et al., p. 1203.

Perceptions of obesity and cancer risk in female bariatric surgery candidates: highlighting the need for physician action for unsuspectingly obese and high risk patients.

OBJECTIVES: To determine: 1) whether obese women perceive themselves to be obese or at risk for malignancy, 2) perceived impact of obesity on cancer risks, 3) compliance with cancer screening, and 4) rates of menstrual dysfunction. METHODS: Surveys were administered to female patients presenting for bariatric weight loss surgery. Demographics, gynecologic history, perception of cancer risk, and screening history were collected/analyzed. Women were categorized as obese (BMI: 30-39kg/m(2)), morbidly obese (40-49kg/m(2)), super obese (≥50kg/m(2)) and compared. RESULTS: Ninety-three women (mean age: 44.9 years, mean BMI: 48.7kg/m(2)) participated and 45.7% felt they were in 'good', 'very good', or 'excellent' health despite frequent medical comorbidities. As BMI increased, women were more likely to correctly identify themselves as obese (23% of obese vs. 77% of morbidly obese vs. 85% of super obese; p<0.001) but there were no significant differences in comorbidities. Two-thirds of women correctly identified obesity as a risk factor for uterine cancer, yet 48% of those retaining a uterus perceived that it was "not likely/not possible" to develop uterine cancer. Menstrual irregularities were common as was evaluation and interventions for the same; 32% had prior hysterectomy. Participation in cancer screening was robust. CONCLUSIONS: Women presenting for bariatric surgery have high rates of menstrual dysfunction. While they perceive that obesity increases uterine cancer risk, they often do not perceive themselves to be at risk. This disconnect may stem from the fact that many failed to identify themselves as obese perhaps because overweight/obesity has become the norm in U.S. society.