Spatial CRISPR genomics identifies regulators of the tumor microenvironment.

While CRISPR screens are helping uncover genes regulating many cell-intrinsic processes, existing approaches are suboptimal for identifying extracellular gene functions, particularly in the tissue context. Here, we developed an approach for spatial functional genomics called Perturb-map. We applied Perturb-map to knock out dozens of genes in parallel in a mouse model of lung cancer and simultaneously assessed how each knockout influenced tumor growth, histopathology, and immune composition. Moreover, we paired Perturb-map and spatial transcriptomics for unbiased analysis of CRISPR-edited tumors. We found that in Tgfbr2 knockout tumors, the tumor microenvironment (TME) was converted to a fibro-mucinous state, and T cells excluded, concomitant with upregulated TGFß and TGFß-mediated fibroblast activation, indicating that TGFß-receptor loss on cancer cells increased TGFß bioavailability and its immunosuppressive effects on the TME. These studies establish Perturb-map for functional genomics within the tissue at single-cell resolution with spatial architecture preserved and provide insight into how TGFß responsiveness of cancer cells can affect the TME.

Innate Immune Landscape in Early Lung Adenocarcinoma by Paired Single-Cell Analyses.

To guide the design of immunotherapy strategies for patients with early stage lung tumors, we developed a multiscale immune profiling strategy to map the immune landscape of early lung adenocarcinoma lesions to search for tumor-driven immune changes. Utilizing a barcoding method that allows a simultaneous single-cell analysis of the tumor, non-involved lung, and blood cells, we provide a detailed immune cell atlas of early lung tumors. We show that stage I lung adenocarcinoma lesions already harbor significantly altered T cell and NK cell compartments. Moreover, we identified changes in tumor-infiltrating myeloid cell (TIM) subsets that likely compromise anti-tumor T cell immunity. Paired single-cell analyses thus offer valuable knowledge of tumor-driven immune changes, providing a powerful tool for the rational design of immune therapies. VIDEO ABSTRACT.

Quiescent Tissue Stem Cells Evade Immune Surveillance.

Stem cells are critical for the maintenance of many tissues, but whether their integrity is maintained in the face of immunity is unclear. Here we found that cycling epithelial stem cells, including Lgr5+ intestinal stem cells, as well as ovary and mammary stem cells, were eliminated by activated T cells, but quiescent stem cells in the hair follicle and muscle were resistant to T cell killing. Immune evasion was an intrinsic property of the quiescent stem cells resulting from systemic downregulation of the antigen presentation machinery, including MHC class I and TAP proteins, and is mediated by the transactivator NLRC5. This process was reversed upon stem cell entry into the cell cycle. These studies identify a link between stem cell quiescence, antigen presentation, and immune evasion. As cancer-initiating cells can derive from stem cells, these findings may help explain how the earliest cancer cells evade immune surveillance.

Screening recall in older cancer survivors detects differences in balance and mobility.

PURPOSE: Cognitive impairments have been reported by up to two-thirds of cancer survivors whose primary cancer did not occur in the central nervous system. Physical impairments as sequelae of cancer-related cognitive impairment (CRCI) have not been well described in previous studies. Furthermore, there is scarcity of literature describing differences among physical performance in those with and without CRCI. The purpose of this study is to examine the differences in physical function of older cancer survivors based on cognitive ability to determine if physical performance differs when different cognitive screening measures are employed. METHODS: Adults age 65 + with a history of cancer from the 2010 Health and Retirement Study (n = 1,953) were assigned to groups according to their cognitive ability. Between-group demographic, mobility, and cognitive differences were analyzed using chi-squared and t tests. Recall and orientation were used as cognitive variables, and physical performance outcomes included gait speed, balance, and grip strength. RESULTS: Respondents with Low Recall had more impaired balance (semi-tandem, tandem) (p < .05) and slower gait speeds (p < .05). Respondents that were Not-Oriented had slower gait speed (p < .05). Between-group differences in demographics were found by recall and orientation groups. CONCLUSIONS: Impairments in balance and gait speed are able to be detected when recall is screened in a population of older cancer survivors. When assessing how physical mobility is related to fall risk, a screen of cognition should go beyond just orientation.

Hydroxychloroquine in the treatment of outpatients with mildly symptomatic COVID-19: a multi-center observational study.

BACKGROUND: Hydroxychloroquine has not been associated with improved survival among hospitalized COVID-19 patients in the majority of observational studies and similarly was not identified as an effective prophylaxis following exposure in a prospective randomized trial. We aimed to explore the role of hydroxychloroquine therapy in mildly symptomatic patients diagnosed in the outpatient setting. METHODS: We examined the association between outpatient hydroxychloroquine exposure and the subsequent progression of disease among mildly symptomatic non-hospitalized patients with documented SARS-CoV-2 infection. The primary outcome assessed was requirement of hospitalization. Data was obtained from a retrospective review of electronic health records within a New Jersey USA multi-hospital network. We compared outcomes in patients who received hydroxychloroquine with those who did not applying a multivariable logistic model with propensity matching. RESULTS: Among 1274 outpatients with documented SARS-CoV-2 infection 7.6% were prescribed hydroxychloroquine. In a 1067 patient propensity matched cohort, 21.6% with outpatient exposure to hydroxychloroquine were hospitalized, and 31.4% without exposure were hospitalized. In the primary multivariable logistic regression analysis with propensity matching there was an association between exposure to hydroxychloroquine and a decreased rate of hospitalization from COVID-19 (OR 0.53; 95% CI, 0.29, 0.95). Sensitivity analyses revealed similar associations. QTc prolongation events occurred in 2% of patients prescribed hydroxychloroquine with no reported arrhythmia events among those with data available. CONCLUSIONS: In this retrospective observational study of SARS-CoV-2 infected non-hospitalized patients hydroxychloroquine exposure was associated with a decreased rate of subsequent hospitalization. Additional exploration of hydroxychloroquine in this mildly symptomatic outpatient population is warranted.

Rapid Systemwide Implementation of Outpatient Telehealth in Response to the COVID-19 Pandemic.

EXECUTIVE SUMMARY: The COVID-19 pandemic, with its resultant social distancing, has disrupted the delivery of healthcare for both patients and providers. Fortunately, changes to legislation and regulation in response to the pandemic allowed Emory Healthcare to rapidly implement telehealth care. Beginning in early March 2020 and continuing through the initial 2-month implementation period (when data collection stopped), clinicians received telehealth training and certification. Standard workflows created by means of a hub-and-spoke operational model enabled rapid sharing and deployment of best practices throughout the system's physician group practice. Lean process huddles facilitated successful implementation. In total, 2,374 healthcare professionals, including 986 attending physicians, 416 residents and fellows, and 555 advanced practice providers, were trained and certified for telehealth; 53,751 new- and established-patient audio-video telehealth visits and 10,539 established-patient telephone visits were performed in 8 weeks for a total of 64,290 virtual visits. This initiative included a new COVID-19 virtual patient clinic that saw 705 patients in a 6-week period. A total of $14,662,967 was charged during this time; collection rates were similar to in-person visits. Initial patient satisfaction scores were equivalent to in-person visits. We conclude that rapid deployment of virtual visits can be accomplished through a structured, organized approach including training, certification, and Lean principles. A hub-and-spoke model enables bidirectional feedback and timely improvements, thus facilitating swifter implementation and a quick rise in patient volume. Financial sustainability is achievable, but to sustain that, telehealth requires the support of continued deregulation by legislative and regulatory bodies.

Discovery of recurrent structural variants in nasopharyngeal carcinoma.

We present the discovery of genes recurrently involved in structural variation in nasopharyngeal carcinoma (NPC) and the identification of a novel type of somatic structural variant. We identified the variants with high complexity mate-pair libraries and a novel computational algorithm specifically designed for tumor-normal comparisons, SMASH. SMASH combines signals from split reads and mate-pair discordance to detect somatic structural variants. We demonstrate a >90% validation rate and a breakpoint reconstruction accuracy of 3 bp by Sanger sequencing. Our approach identified three in-frame gene fusions (YAP1-MAML2, PTPLB-RSRC1, and SP3-PTK2) that had strong levels of expression in corresponding NPC tissues. We found two cases of a novel type of structural variant, which we call "coupled inversion," one of which produced the YAP1-MAML2 fusion. To investigate whether the identified fusion genes are recurrent, we performed fluorescent in situ hybridization (FISH) to screen 196 independent NPC cases. We observed recurrent rearrangements of MAML2 (three cases), PTK2 (six cases), and SP3 (two cases), corresponding to a combined rate of structural variation recurrence of 6% among tested NPC tissues.

Genome evolution during progression to breast cancer.

Cancer evolution involves cycles of genomic damage, epigenetic deregulation, and increased cellular proliferation that eventually culminate in the carcinoma phenotype. Early neoplasias, which are often found concurrently with carcinomas and are histologically distinguishable from normal breast tissue, are less advanced in phenotype than carcinomas and are thought to represent precursor stages. To elucidate their role in cancer evolution we performed comparative whole-genome sequencing of early neoplasias, matched normal tissue, and carcinomas from six patients, for a total of 31 samples. By using somatic mutations as lineage markers we built trees that relate the tissue samples within each patient. On the basis of these lineage trees we inferred the order, timing, and rates of genomic events. In four out of six cases, an early neoplasia and the carcinoma share a mutated common ancestor with recurring aneuploidies, and in all six cases evolution accelerated in the carcinoma lineage. Transition spectra of somatic mutations are stable and consistent across cases, suggesting that accumulation of somatic mutations is a result of increased ancestral cell division rather than specific mutational mechanisms. In contrast to highly advanced tumors that are the focus of much of the current cancer genome sequencing, neither the early neoplasia genomes nor the carcinomas are enriched with potentially functional somatic point mutations. Aneuploidies that occur in common ancestors of neoplastic and tumor cells are the earliest events that affect a large number of genes and may predispose breast tissue to eventual development of invasive carcinoma.

Breakpoint analysis of transcriptional and genomic profiles uncovers novel gene fusions spanning multiple human cancer types.

Gene fusions, like BCR/ABL1 in chronic myelogenous leukemia, have long been recognized in hematologic and mesenchymal malignancies. The recent finding of gene fusions in prostate and lung cancers has motivated the search for pathogenic gene fusions in other malignancies. Here, we developed a "breakpoint analysis" pipeline to discover candidate gene fusions by tell-tale transcript level or genomic DNA copy number transitions occurring within genes. Mining data from 974 diverse cancer samples, we identified 198 candidate fusions involving annotated cancer genes. From these, we validated and further characterized novel gene fusions involving ROS1 tyrosine kinase in angiosarcoma (CEP85L/ROS1), SLC1A2 glutamate transporter in colon cancer (APIP/SLC1A2), RAF1 kinase in pancreatic cancer (ATG7/RAF1) and anaplastic astrocytoma (BCL6/RAF1), EWSR1 in melanoma (EWSR1/CREM), CDK6 kinase in T-cell acute lymphoblastic leukemia (FAM133B/CDK6), and CLTC in breast cancer (CLTC/VMP1). Notably, while these fusions involved known cancer genes, all occurred with novel fusion partners and in previously unreported cancer types. Moreover, several constituted druggable targets (including kinases), with therapeutic implications for their respective malignancies. Lastly, breakpoint analysis identified new cell line models for known rearrangements, including EGFRvIII and FIP1L1/PDGFRA. Taken together, we provide a robust approach for gene fusion discovery, and our results highlight a more widespread role of fusion genes in cancer pathogenesis.

The effect of locoregional therapies in patients with advanced hepatocellular carcinoma treated with sorafenib.

BACKGROUND & AIMS: It is unknown whether the addition of locoregional therapies (LRTx) to sorafenib improves prognosis over sorafenib alone in patients with advanced hepatocellular carcinoma (HCC). The aim of this study was to assess the effect of LRTx in this population. METHODS: A retrospective analysis was performed of patients with advanced HCC as defined by extrahepatic metastasis, lymphadenopathy >2 cm, or gross vascular invasion. Sorafenib therapy was required for inclusion. Survival of patients who received LRTx after progression to advanced stage was compared to those who did not receive LRTx. RESULTS: Using an intention to treat analysis of 312 eligible patients, a propensity weighted proportional hazards model demonstrated LRTx as a predictor of survival (HR = 0.505, 95% CI: 0.407-0.628; P < 0.001). The greatest benefit was seen in patients with the largest tumor burden (HR = 0.305, 95% CI: 0.236-0.393; P < 0.01). Median survival in the sorafenib arm was 143 days (95% CI: 118-161) vs. 247 days (95% CI: 220-289) in the sorafenib plus LRTx arm (P < 0.001). CONCLUSIONS: These results demonstrate a survival benefit with the addition of LRTx to sorafenib for patients with advanced HCC. These findings should prompt a prospective clinical trial to further assess the role of LRTx in patients with advanced HCC.

Molecular pathological analysis of sarcomas using paraffin-embedded tissue: current limitations and future possibilities.

Sarcomas of soft tissue and bone are rare neoplasms that can be separated into a large number of different diagnostic entities. Over the years, a number of diagnostic markers have been developed that aid pathologists in reaching the appropriate diagnoses. Many of these markers are sarcoma-specific proteins that can be detected by immunohistochemistry in formalin-fixed, paraffin-embedded (FFPE) sections. In addition, a wide range of molecular studies have been developed that can detect gene mutations, gene amplifications or chromosomal translocations in FFPE material. Until recently, most sequencing-based approaches relied on the availability of fresh frozen tissue. However, with the advent of next-generation sequencing technologies, FFPE material is increasingly being used as a tool to identify novel immunohistochemistry markers, gene mutations, and chromosomal translocations, and to develop diagnostic tests.

Cytoreductive surgery with or without hyperthermic intraperitoneal chemotherapy in patients with peritoneal hepatocellular carcinoma.

BACKGROUND AND OBJECTIVES: The benefit of Sorafenib is not well described in patients with peritoneal hepatocellular carcinoma (HCC). Although cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have shown favorable outcomes in certain malignancies, their role in peritoneal HCC remains unknown. We present a series of patients with peritoneal HCC treated with CRS +/- HIPEC and evaluate their clinicopathologic characteristics and outcomes. METHODS: Between 07/07-08/12, 14 patients with limited disease to the peritoneum underwent CRS. Seven of these patients received additional HIPEC treatment. Primary endpoint was overall survival. RESULTS: Operative treatment was directed for metachronous peritoneal disease in the majority (92.8%) of patients. Mean intraoperative PCI was 9.9 (± 8.3) and complete mascroscopic cytoreduction (CCR 0-1) was achieved in all but one case. Overall major morbidity rate (Clavien-Dindo III-IV) at 30 days was 7.1%. One postoperative death occurred in a patient with extensive tumor burden (PCI = 33, CCR2). Median follow-up after initial surgery was 43.8 months and the median time to metachronous peritoneal recurrence was 23 months. Three-year recurrence rate after peritoneal resection was 100%. Median survival of the cohort CCR0-1 was 35.6 months. CONCLUSION: Treatment of peritoneal HCC remains challenging and survival is poor. In well-selected candidates, however, CRS +/- HIPEC may prolong survival compared to systemic therapy alone in patients with peritoneal HCC.

Single cell view of tumor microenvironment gradients in pleural mesothelioma.

Immunotherapies have shown great promise in pleural mesothelioma (PM), yet most patients still do not achieve significant clinical response, highlighting the importance of improving understanding of the tumor microenvironment (TME). Here, we utilized high-throughput, single-cell RNA-sequencing to de novo identify 54 expression programs and construct a comprehensive cellular catalogue of the PM TME. We found four cancer-intrinsic programs associated with poor disease outcome and a novel fetal-like, endothelial cell population that likely responds to VEGF signaling and promotes angiogenesis. Throughout cellular compartments, we observe substantial difference in the TME associated with a cancer-intrinsic sarcomatoid signature, including enrichment in fetal-like endothelial cells, CXCL9+ macrophages, cytotoxic, exhausted, and regulatory T cells, which we validated using imaging and bulk deconvolution analyses on independent cohorts. Finally, we show, both computationally and experimentally, that NKG2A-HLA-E interaction between NK and tumor cells represents an important new therapeutic axis in PM, especially for epithelioid cases.

Histologic analysis of fetal bovine derived acellular dermal matrix in tissue expander breast reconstruction.

BACKGROUND: This study seeks to determine human host response to fetal bovine acellular dermal matrix (ADM) in staged implant-based breast reconstruction. METHODS: A prospective study was performed for patients undergoing immediate breast reconstruction with tissue expander placement and SurgiMend acellular fetal bovine dermis. At the time of exchange for permanent implant, we obtained tissue specimens of SurgiMend and native capsule. Histological and immunohistochemical assays were performed to characterize the extent of ADM incorporation/degradation, host cell infiltration, neovascularization, inflammation, and host replacement of acellular fetal bovine collagen. RESULTS: Seventeen capsules from 12 patients were included in our study. The average "implantation" time of SurgiMend was 7.8 months (range, 2-23 months). Histological analysis of the biopsy of tissue revealed rare infiltration of host inflammatory cells, even at 23 months. One patient had an infection requiring removal of the tissue expander at 2 months. Contracture, inflammatory changes, edema, and polymorphonuclear leukocyte infiltration were rare in the ADM. An acellular capsule was seen in many cases, at the interface of SurgiMend with the tissue expander. CONCLUSIONS: SurgiMend demonstrated a very infrequent inflammatory response. An antibody specific to bovine collagen allowed for direct identification of bovine collagen separate from human collagen. Cellular infiltration and neovascularization of SurgiMend correlated with the quality of the mastectomy skin flap rather than the duration of implantation. Future studies are needed to further characterize the molecular mechanisms underlying tissue incorporation of this product.

Emergency medical services for children: the New Jersey model.

Identification of specific facilities within a community for the emergency department (ED) treatment of children is a traditional component of Emergency Medical Services for Children systems. In such models, these Emergency Departments Approved for Pediatrics are the preferred EDs to receive patients from Emergency Medical Services providers. This article examines an alternative model developed in New Jersey in which every ED in the state is required by regulation to meet the standards of a traditional Emergency Departments Approved for Pediatrics. The New Jersey model leads to more accessible care and more rapid stabilization of children regardless of their mode of delivery to the ED.

Multiplexed Immunohistochemical Consecutive Staining on Single Slide (MICSSS): Multiplexed Chromogenic IHC Assay for High-Dimensional Tissue Analysis.

Disease states and cellular compartments can display a remarkable amount of heterogeneity, and truly appreciating this heterogeneity requires the ability to detect and probe each subpopulation present. A myriad of recent single-cell assays has allowed for in-depth analysis of these diverse cellular populations; however, fully understanding the interplay between each cell type requires knowledge not only of their mere presence but also of their spatial organization and their relation one to the other. Immunohistochemistry allows for the visualization of cells and tissue; however, standard techniques only allow for the use of very few probes on a single specimen, not allowing for in-depth analysis of complex cellular heterogeneity. A number of multiplex imaging techniques, such as immunofluorescence and multiplex immunohistochemistry, have been proposed to allow probing more cellular markers at once; however, many of these techniques still have their limitations. The use of fluorescent markers has an inherent limitation to the number of probes that can be simultaneously used due to spectral overlap. Moreover, other proposed multiplex IHC methods are time-consuming and require expensive reagents. Still, many of the methods rely on frozen tissue, which deviates from standards in human pathological evaluation. Here, we describe a multiplex IHC technique, staining for consecutive markers on a single slide, which utilizes similar steps and similar reagents as standard IHC, thus making it possible for any lab with standard IHC capabilities to perform this useful procedure. This method has been validated and confirmed that consecutive markers can be stained without the risk of cross-reactivity between staining cycles. Furthermore, we have validated that this technique does not lead to decreased antigenicity of subsequent epitopes probed, nor does it lead to steric hindrance.

Genomic analysis of benign prostatic hyperplasia implicates cellular re-landscaping in disease pathogenesis.

Benign prostatic hyperplasia (BPH) is the most common cause of lower urinary tract symptoms in men. Current treatments target prostate physiology rather than BPH pathophysiology and are only partially effective. Here, we applied next-generation sequencing to gain new insight into BPH. By RNAseq, we uncovered transcriptional heterogeneity among BPH cases, where a 65-gene BPH stromal signature correlated with symptom severity. Stromal signaling molecules BMP5 and CXCL13 were enriched in BPH while estrogen regulated pathways were depleted. Notably, BMP5 addition to cultured prostatic myofibroblasts altered their expression profile towards a BPH profile that included the BPH stromal signature. RNAseq also suggested an altered cellular milieu in BPH, which we verified by immunohistochemistry and single-cell RNAseq. In particular, BPH tissues exhibited enrichment of myofibroblast subsets, whilst depletion of neuroendocrine cells and an estrogen receptor (ESR1)-positive fibroblast cell type residing near epithelium. By whole-exome sequencing, we uncovered somatic single-nucleotide variants (SNVs) in BPH, of uncertain pathogenic significance but indicative of clonal cell expansions. Thus, genomic characterization of BPH has identified a clinically-relevant stromal signature and new candidate disease pathways (including a likely role for BMP5 signaling), and reveals BPH to be not merely a hyperplasia, but rather a fundamental re-landscaping of cell types.

GFP-specific CD8 T cells enable targeted cell depletion and visualization of T-cell interactions.

There are numerous cell types with scarcely understood functions, whose interactions with the immune system are not well characterized. To facilitate their study, we generated a mouse bearing enhanced green fluorescent protein (EGFP)-specific CD8+ T cells. Transfer of the T cells into EGFP reporter animals can be used to kill EGFP-expressing cells, allowing selective depletion of desired cell types, or to interrogate T-cell interactions with specific populations. Using this system, we eliminate a rare EGFP-expressing cell type in the heart and demonstrate its role in cardiac function. We also show that naive T cells are recruited into the mouse brain by antigen-expressing microglia, providing evidence of an immune surveillance pathway in the central nervous system. The just EGFP death-inducing (Jedi) T cells enable visualization of a T-cell antigen. They also make it possible to utilize hundreds of existing EGFP-expressing mice, tumors, pathogens and other tools, to study T-cell interactions with many different cell types, to model disease states and to determine the functions of poorly characterized cell populations.

The impact of surgical diversion before neoadjuvant therapy for rectal cancer.

Up-front fecal diversion can palliate emergent symptoms related to locally advanced rectal cancer (LARC) allowing patients to receive neoadjuvant chemoradiation therapy (nCRT). We analyzed outcomes of pretreatment-diverted LARC patients relative to nondiverted patients to define the impact of this management strategy. We retrospectively collected data on 103 LARC patients treated with nCRT and surgery. Medical records were reviewed for patient characteristics, staging, treatment plan, and outcomes. Thirteen LARC patients underwent pretreatment diversion for urgent symptoms and 90 LARC patients proceeded directly to nCRT. In all, 50 per cent of diverted patients presented with T4 tumor compared with 14 per cent in the nondiverted patients (P = 0.003). Diverted patients experienced a delay in time-to-treatment initiation of 12 days, although this difference was not statistically significant. Similar rates of chemoradiation and surgical toxicities were observed. Even though diverted patients demonstrated less pathologic response to nCRT compared with nondiverted patients (P = 0.04), there was no significant difference in overall survival. In conclusion, our study demonstrates the effectiveness of up-front fecal diversion at managing emergent obstructive symptoms related to advanced rectal cancer without additional complications, allowing patients to proceed with nCRT followed by radical surgery.