Reprogramming of Tumor-reactive Tumor-infiltrating Lymphocytes to Human-induced Pluripotent Stem Cells.

Tumor-infiltrating lymphocytes (TIL) that can recognize and kill tumor cells have curative potential in subsets of patients treated with adoptive cell transfer (ACT). However, lack of TIL therapeutic efficacy in many patients may be due in large part to a paucity of tumor-reactive T cells in TIL and the exhausted and terminally differentiated status of those tumor-reactive T cells. We sought to reprogram exhausted TIL that possess T-cell receptors (TCR) specific for tumor antigens into induced pluripotent stem cells (iPSC) to rejuvenate them for more potent ACT. We first attempted to reprogram tumor neoantigen-specific TIL by αCD3 Ab prestimulation which resulted in failure of establishing tumor-reactive TIL-iPSCs, instead, T cell-derived iPSCs from bystander T cells were established. To selectively activate and enrich tumor-reactive T cells from the heterogenous TIL population, CD8+ PD-1+ 4-1BB+ TIL population were isolated after coculture with autologous tumor cells, followed by direct reprogramming into iPSCs. TCR sequencing analysis of the resulting iPSC clones revealed that reprogrammed TIL-iPSCs encoded TCRs that were identical to the pre-identified tumor-reactive TCRs found in minimally cultured TIL. Moreover, reprogrammed TIL-iPSCs contained rare tumor antigen-specific TCRs, which were not detectable by TCR sequencing of the starting cell population. Thus, reprogramming of PD-1+ 4-1BB+ TIL after coculture with autologous tumor cells selectively generates tumor antigen-specific TIL-iPSCs, and is a distinctive method to enrich and identify tumor antigen-specific TCRs of low frequency from TIL. Significance: Reprogramming of TIL into iPSC holds great promise for the future treatment of cancer due to their rejuvenated nature and the retention of tumor-specific TCRs. One limitation is the lack of selective and efficient methods for reprogramming tumor-specific T cells from polyclonal TIL. Here we addressed this limitation and present a method to efficiently reprogram TIL into iPSC colonies carrying diverse tumor antigen reactive TCR recombination.

Self-organized yolk sac-like organoids allow for scalable generation of multipotent hematopoietic progenitor cells from induced pluripotent stem cells.

Although the differentiation of human induced pluripotent stem cells (hiPSCs) into various types of blood cells has been well established, approaches for clinical-scale production of multipotent hematopoietic progenitor cells (HPCs) remain challenging. We found that hiPSCs cocultured with stromal cells as spheroids (hematopoietic spheroids [Hp-spheroids]) can grow in a stirred bioreactor and develop into yolk sac-like organoids without the addition of exogenous factors. Hp-spheroid-induced organoids recapitulated a yolk sac-characteristic cellular complement and structures as well as the functional ability to generate HPCs with lympho-myeloid potential. Moreover, sequential hemato-vascular ontogenesis could also be observed during organoid formation. We demonstrated that organoid-induced HPCs can be differentiated into erythroid cells, macrophages, and T lymphocytes with current maturation protocols. Notably, the Hp-spheroid system can be performed in an autologous and xeno-free manner, thereby improving the feasibility of bulk production of hiPSC-derived HPCs in clinical, therapeutic contexts.

Carbon Dioxide Embolism Resulting From Liver Laceration During Peritoneal Optical Trocar Entry.

Venous air emboli have been reported to occur in numerous settings, including trauma, various surgical procedures, both laparoscopic and radiologically, and even idiopathically. In this case study, a liver laceration was made during a robot-assisted left colectomy and colostomy in a 69-year-old female resulting in air embolism during insufflation. A drop in end-tidal CO2 was noted and the patient went into immediate cardiac arrest. Adequate pressure was applied and over-suturing of the liver laceration was made with reverse Trendelenburg positioning during the administration of cardiopulmonary resuscitation (CPR) for approximately one minute. The patient completed an open hemicolectomy the following day and made a complete recovery. Preventative and intraoperative measures to prevent further recurrences of venous air emboli are discussed.

Pancreatic insufficiency following pancreatectomy: Does underlying tumor syndrome confer a greater risk?

BACKGROUND: The risk of postoperative pancreatic exocrine insufficiency (PPEI) is unknown in patients with multiple endocrine neoplasia type I (MEN1) and von Hippel-Lindau (VHL) who require resection of pancreatic neuroendocrine tumors (PNETs). METHODS: A retrospective review of patients who underwent resection of PNETs at the National Institutes of Health from 2007 to 2019 was performed. RESULTS: Our cohort included 82 patients (VHL n = 25, MEN1 n = 20, sporadic n = 37), 6 of whom developed PPEI. While VHL compared to all non-VHL patients (p = 0.046), non-functional PNETs (p = 0.050), and pancreaticoduodenectomy (PD) (p=<0.001) were associated with higher rates of PPEI on univariate analysis, only PD was found to be an independent predictor of PPEI on multivariate analysis (OR 14.43, 95% CI 1.43-145.8, p = 0.024). CONCLUSIONS: The rate of PPEI in patients with hereditary tumor syndromes was similar to that of sporadic PNETs. PD was independently associated with PPEI, and this increased risk should be included in preoperative counseling.

Intrahepatic cholangiocarcinoma as a rare secondary malignancy after allogeneic hematopoietic stem cell transplantation for childhood acute lymphoblastic leukemia: A case report.

Secondary malignancies are a significant cause of non-relapse mortality in patients who undergo allogeneic HCT. However, secondary liver cancer is rare, and ICC following HCT has never been reported in the literature. Secondary solid cancers typically have a long latency period, and cholangiocarcinoma is classically a malignancy occurring in older individuals. Here, we report the first case of secondary ICC, which presented just 3 years after HCT in a young adult with a history of childhood ALL. A 26-year-old male with history of precursor B-cell ALL presented with asymptomatic elevated liver function tests 3 years after HCT. Laboratories were indicative of biliary obstruction. ERCP showed focal biliary stricturing of the common and left hepatic ducts. MRCP revealed left intrahepatic duct dilatation, suggestive of intrahepatic obstructing mass. Additional workup lead to a clinical diagnosis of ICC. The patient underwent left hepatectomy with extrahepatic bile duct resection and portal lymphadenectomy. Surgical pathology was consistent with moderately differentiated cholangiocarcinoma. Our case illustrates a rare SMN following HCT for ALL. It is the first case report of ICC occurring as a secondary cancer in this patient population. Although cholangiocarcinoma is characteristically diagnosed in the older population, it must remain on the differential for biliary obstruction in post-HCT patients.

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.

Twenty-five-Year Follow-up of a Prospective Randomized Trial Comparing Preoperative Versus Postoperative FLAC/Granulocyte Colony-Stimulating Factor Chemotherapy for Stage II Breast Cancer.

BACKGROUND: Preoperative chemotherapy is important in the management of women with breast cancer, with the ability to downstage the breast primary tumor and axillary lymph nodes. Long-term studies are needed to identify late toxicities, recurrence patterns, and equivalency with postoperative chemotherapy for recurrence-free survival (RFS) and overall survival (OS). PATIENTS AND METHODS: We conducted a single-institution prospective randomized control trial comparing preoperative or postoperative fluorouracil, leucovorin calcium, doxorubicin, and cyclophosphamides/granulocyte colony-stimulating factor chemotherapy for women with untreated clinical stage II (T1N1, T2N0, and T2N1) breast cancer. Long-term follow-up was conducted to define toxicities, recurrence patterns and RFS and OS. RESULTS: Fifty-three women with clinical stage II breast cancer were randomized, 26 patients to receive preoperative chemotherapy and 27 to receive postoperative chemotherapy. Long-term follow-up, with a median of 25.3 years, was obtained. Local or systemic recurrence occurred in 8 women in the preoperative group and in 10 women in the postoperative group, and recurrences were predominantly within 10 years of treatment. Late toxicities included local upper extremity paresthesia's, upper extremity edema and congestive heart failure in 1 patient each. Analysis revealed no difference in RFS (20-year RFS probabilities; preoperative: 61.3%, postoperative: 54.7%, P=0.42), or in OS between the 2 treatment groups (20-year probabilities, preoperative: 64.6%, postoperative: 62.2%, P=0.44). Twenty-five of 53 patients (47%) were alive and without disease at this follow-up. CONCLUSION: Twenty-five-year follow-up for this prospective randomized trial confirms the equivalency of preoperative versus postoperative chemotherapy with fluorouracil, leucovorin calcium, doxorubicin, and cyclophosphamides/granulocyte colony-stimulating factor for stage II breast cancer for both RFS and OS.

Surgical Resection of Pheochromocytomas and Paragangliomas is Associated with Lower Cholesterol Levels.

BACKGROUND: Catecholamine excess in patients with pheochromocytomas or paragangliomas (PPGLs) can lead to hypertension, diabetes and hyperlipidemia. The aim was to investigate the prevalence of hyperlipidemia and the effect of surgical resection. METHODS: One hundred and thirty-two patients with PPGLs underwent an operation at the National Institutes of Health from 2009 to 2016, of which 54 patients met the inclusion criteria. Clinical demographics, BMI, genetic mutations, tumor size, perioperative catecholamine levels and perioperative lipid panels were retrospectively reviewed. Spearman correlation between catecholamines and lipid levels was evaluated. Paired Wilcoxon and paired t test were used to analyze differences in pre- and postoperative lipid levels. RESULTS: Preoperatively, 51 patients (94.4%) had elevated catecholamines, thirteen (24.1%) had elevated total cholesterol (TC) (>200 mg/dL), nine (16.6%) had elevated LDL (>130 mg/dL) and ten (18.5%) had elevated triglycerides (>150 mg/dL). Serum and urinary metanephrine levels were positively associated with TC (r = 0.2792, p = 0.0372 and r = 0.4146, p = 0.0031, respectively) and LDL levels (r = 0.2977, p = 0.0259 and r = 0.4434, p = 0.0014, respectively). Mean TC decreased from 176.4 to 166.3 mg/dL (p = 0.0064) and mean HDL decreased from 56.7 to 53.2 mg/dL (p = 0.0253) after PPGL resection (median 3.1 months (range 1.3-50.2) between lipid panels). Most patients with elevated TC (76.9%) had improvement with mean TC decreasing from 225 to 200.2 mg/dL (p = 0.0230). Of patients with elevated LDL, 66.7% had improvement with mean LDL decreasing from 149 to 131.1 mg/dL (p = 0.0313). CONCLUSIONS: The prevalence of hyperlipidemia in patients with PPGLs is 46%. Future prospective studies are needed to determine whether surgical resection improves TC and/or LDL levels.

Resection and chemotherapy is the optimal treatment approach for patients with clinically node positive intrahepatic cholangiocarcinoma.

BACKGROUND: Clinically lymph node positive (cLNP) intrahepatic cholangiocarcinoma (ICC) carries a poor prognosis, without clear management guidelines for the practicing clinician. We sought to evaluate current practice patterns for cLNP ICC, including associations with survival. METHODS: The National Cancer Database was queried for patients with cLNP ICC, without extrahepatic metastases. RESULTS: We identified 1023 patients with cLNP ICC, 77%% (n = 784) of whom received chemotherapy alone. Resection was undertaken in 23% (n = 239) of patients and was most commonly utilized in combination with chemotherapy (n = 150). Median survival for all patients was 13.6 months. Patients undergoing resection in combination with chemotherapy were associated with an improved survival (22.5 months) as compared to those patients receiving chemotherapy alone (11.9 months) or resection alone (12.4 months) (p < 0.01). Finally, we compared the survival of patients with cLNP ICC with that of patients with pathologically proved lymph node positive (pLNP) ICC, all of whom were treated with resection with chemotherapy, and found no difference in survival (22.5 months-19.3 months, p = 0.99, respectively). CONCLUSIONS: While the decision to pursue resection for ICC is multifactorial and patient specific, the presence of clinically positive LNs should not represent a contraindication.

Stage and disease-free interval help select patients for surgical management of locally recurrent and metastatic adrenocortical carcinoma.

BACKGROUND AND OBJECTIVES: Chemotherapeutic options for patients with recurrent/metastatic adrenocortical carcinoma (ACC) are limited, leading to consideration for surgical management. We sought to determine characteristics associated with an unequivocal survival benefit amongst patients undergoing re-resection or metastasectomy. METHODS: Patients who underwent surgery for recurrent/metastatic ACC were identified and stratified into two groups: those with postoperative survival comparable with what has been reported with chemotherapy alone (<12 months) and those surviving twice that duration (>24 months). Those who survived between 12 and 24 months were excluded, as the objective was to characterize patients who most distinctly benefited from resection. Clinicopathologic and treatment variables were evaluated for associations with survival. RESULTS: Forty-three patients survived more than 24 months and 15 patients died less than 12 months after reoperation. Tumor stage (odds ratio [OR], 0.66; 95% confidence interval [CI], 0.45-0.96) and disease-free interval (DFI; OR, 3.23; 95% CI, 1.68-6.22) were associated with prolonged survival. Tumor size, hormonal status, resection margin, and treatment with chemotherapy, radiation, and mitotane were not associated with prolonged survival. Patients who survived more than 24 months underwent more procedures for subsequent recurrences (median 4 vs 2; P < .001). CONCLUSION: Stage and DFI can help select optimal candidates for resection of recurrent/metastatic ACC. Patients selected for surgical management should be informed of the likelihood of requiring multiple interventions.

Using Human Induced Pluripotent Stem Cells for the Generation of Tumor Antigen-specific T Cells.

The generation and expansion of functional T cells in vitro can lead to a broad range of clinical applications. One such use is for the treatment of patients with advanced cancer. Adoptive T cell transfer (ACT) of highly enriched tumor antigen-specific T cells has been shown to cause durable regression of metastatic cancer in some patients. However, during expansion, these cells may become exhausted or senescent, limiting their effector function and persistence in vivo. Induced pluripotent stem cell (iPSC) technology may overcome these obstacles by leading to in vitro generation of large numbers of less differentiated tumor antigen-specific T cells. Human iPSC (hiPSC) have the capacity to differentiate into any type of somatic cell, including lymphocytes, which retain the original T cell receptor (TCR) genomic rearrangement when a T cell is used as a starting cell. Therefore, reprogramming of human tumor antigen-specific T cells to hiPSC followed by redifferentiation to T cell lineage has the potential to produce rejuvenated tumor antigen-specific T cells. Described here is a method for generating tumor antigen-specific CD8αß+ single positive (SP) T cells from hiPSC using OP9/DLL1 co-culture system. This method is a powerful tool for in vitro T cell lineage generation and will facilitate the development of in vitro derived T cells for use in regenerative medicine and cell-based therapies.

A Three-dimensional Thymic Culture System to Generate Murine Induced Pluripotent Stem Cell-derived Tumor Antigen-specific Thymic Emigrants.

The inheritance of pre-rearranged T cell receptors (TCRs) and their epigenetic rejuvenation make induced pluripotent stem cell (iPSC)-derived T cells a promising source for adoptive T cell therapy (ACT). However, classical in vitro methods for producing regenerated T cells from iPSC result in either innate-like or terminally differentiated T cells, which are phenotypically and functionally distinct from naïve T cells. Recently, a novel three-dimensional (3D) thymic culture system was developed to generate a homogenous subset of CD8αß+ antigen-specific T cells with a naïve T cell-like functional phenotype, including the capacity for proliferation, memory formation, and tumor suppression in vivo. This protocol avoids aberrant developmental fates, allowing for the generation of clinically relevant iPSC-derived T cells, designated as iPSC-derived thymic emigrants (iTE), while also providing a potent tool to elucidate the subsequent functions necessary for T cell maturation after thymic selection.

MicroRNA-210 May Be a Preoperative Biomarker of Malignant Pheochromocytomas and Paragangliomas.

BACKGROUND: Currently, no reliable predictive clinical or laboratory tests exist that can accurately distinguish between benign and malignant pheochromocytomas or paragangliomas (PPGLs). The aim of this study was to investigate if serum microRNA-210 (miR-210) levels could be a marker of malignancy in patients with PPGLs. METHODS: Preoperative serum from patients with PPGLs was collected on the day of surgery. Clinical demographics, germline mutation status, primary tumor size, postoperative biochemical response, and the development of malignant disease were prospectively collected. Total microRNA was extracted from preoperative serum samples, and miR-210 levels were measured by quantitative real-time reverse transcription-polymerase chain reaction and normalized to miR-16. Prognostic variables were compared using univariable and multivariable analyses. RESULTS: Of the 35 patients, 10 (29%) were diagnosed with malignant PPGLs and 25 patients (71%) were diagnosed with benign PPGLs (median follow-up 72.5 mo). Sixty-nine percent of patients had a pheochromocytoma (n = 24/35) compared with 31% of patients with paraganglioma (n = 11/35). The most common germline mutation was succinate dehydrogenase complex subunit B (SDHB) (n = 10). On univariable analysis, lower serum miR-210 expression level (2.3 ± 0.5 versus 3.1 ± 1.2, P = 0.013) and larger primary tumor size (6.7 ± 5.0 cm versus 4.1 ± 2.3 cm, P = 0.043) were significantly associated with malignant disease. No significant prognostic variables were found on multivariable analysis. CONCLUSIONS: In this pilot study, low serum miR-210 expression levels and large primary tumors were identified to be markers of PPGL malignancy on univariable analysis. Given the initial encouraging results in a small cohort, further investigation is warranted to determine if serum miR-210 levels are prognostic.

Tumor Size and Presence of Metastatic Disease at Diagnosis are Associated with Disease-Specific Survival in Parathyroid Carcinoma.

BACKGROUND: The incidence of parathyroid carcinoma is reported to be rising. There is minimal data on prognostic variables associated with cancer-specific survival. The objectives of this study were to evaluate the trends in incidence and assess prognostic factors. METHODS: A retrospective review of the SEER database between 1973 and 2014 was performed, identifying 520 patients with parathyroid carcinoma. Population-adjusted incidence rates were calculated in 4-year intervals. A Cochrane-Armitage test was performed to analyze changes in trend in incidence, tumor size, and extent of disease. Age, year of diagnosis, race, gender, extent of disease, surgical resection, treatment with radiation, tumor size, and lymph node status were assessed using Mantel-Cox log rank test. Multivariate analysis was performed by Cox regression analysis. RESULTS: The incidence of parathyroid carcinoma has been increasing since 1974 from 2 to 11 cases per 10 million people but has since stabilized at 11 cases per 10 million people since 2001. The increasing incidence was attributed to locoregional disease and tumor size < 3 cm. The presence of metastatic disease [hazard ratio (HR) 111.4, 95% confidence interval (CI) 20.6-601.8, p < 0.0001) and tumor size > 3 cm (HR 5.6, 95% CI 1.5-21.2, p = 0.011] were associated with worse cancer-specific survival by univariate and multivariate analyses. CONCLUSIONS: The incidence of parathyroid carcinoma has remained stable over the past decade. Tumor size < 3 cm and regional disease have increased in incidence. Patients with metastatic disease and tumors > 3 cm have worse cancer-specific survival. These findings can be incorporated in the development of a staging system for parathyroid carcinoma.

Generation of Tumor Antigen-Specific iPSC-Derived Thymic Emigrants Using a 3D Thymic Culture System.

Induced pluripotent stem cell (iPSC)-derived T cells may provide future therapies for cancer patients, but those generated by current methods, such as the OP9/DLL1 system, have shown abnormalities that pose major barriers for clinical translation. Our data indicate that these iPSC-derived CD8 single-positive T cells are more like CD4+CD8+ double-positive T cells than mature naive T cells because they display phenotypic markers of developmental arrest and an innate-like phenotype after stimulation. We developed a 3D thymic culture system to avoid these aberrant developmental fates, generating a homogeneous subset of CD8αß+ antigen-specific T cells, designated iPSC-derived thymic emigrants (iTEs). iTEs exhibit phenotypic and functional similarities to naive T cells both in vitro and in vivo, including the capacity for expansion, memory formation, and tumor suppression. These data illustrate the limitations of current methods and provide a tool to develop the next generation of iPSC-based antigen-specific immunotherapies.