Significance of the Percentage of Gleason Pattern 4 at Prostate Biopsy in Predicting Adverse Pathology on Radical Prostatectomy: Application in Active Surveillance.

OBJECTIVES: To determine the prognostic significance of the maximum allowable percentage of Gleason pattern 4 (GP4) at prostate biopsy compared with adverse pathology observed at radical prostatectomy (RP) to expand active surveillance eligibility among a cohort with intermediate risk of prostate cancer. METHODS: A retrospective study of patients with grade group (GG) 1 or 2 prostate cancer on prostate biopsy with subsequent RP was performed at our institution. A Fisher exact test was used to understand the relationship among GP4 subgroups (0%, ≤5%, 6%-10%, and 11%-49%) assigned at biopsy and adverse pathologic findings at RP. Additional analyses comparing the GP4 ≤5% cohort's prebiopsy prostate-specific antigen (PSA) level and GP4 length with adverse pathology at RP were also performed. RESULTS: No statistically significant difference in adverse pathology at RP was observed between the active surveillance-eligible control (GP4 0%) and the GP4 ≤5% subgroup. In total, 68.9% of the GP4 ≤5% cohort showed favorable pathologic outcomes. A separate analysis of the GP4 ≤5% subgroup revealed that neither prebiopsy serum PSA levels nor GP4 length showed statistical correlation with adverse pathology at RP. CONCLUSIONS: Active surveillance may be a reasonable option for management of patients in the GP4 ≤5% group until long-term follow-up data become available.

Epigenomic charting and functional annotation of risk loci in renal cell carcinoma.

While the mutational and transcriptional landscapes of renal cell carcinoma (RCC) are well-known, the epigenome is poorly understood. We characterize the epigenome of clear cell (ccRCC), papillary (pRCC), and chromophobe RCC (chRCC) by using ChIP-seq, ATAC-Seq, RNA-seq, and SNP arrays. We integrate 153 individual data sets from 42 patients and nominate 50 histology-specific master transcription factors (MTF) to define RCC histologic subtypes, including EPAS1 and ETS-1 in ccRCC, HNF1B in pRCC, and FOXI1 in chRCC. We confirm histology-specific MTFs via immunohistochemistry including a ccRCC-specific TF, BHLHE41. FOXI1 overexpression with knock-down of EPAS1 in the 786-O ccRCC cell line induces transcriptional upregulation of chRCC-specific genes, TFCP2L1, ATP6V0D2, KIT, and INSRR, implicating FOXI1 as a MTF for chRCC. Integrating RCC GWAS risk SNPs with H3K27ac ChIP-seq and ATAC-seq data reveals that risk-variants are significantly enriched in allelically-imbalanced peaks. This epigenomic atlas in primary human samples provides a resource for future investigation.

Pulmonary Pathology of End-Stage COVID-19 Disease in Explanted Lungs and Outcomes After Lung Transplantation.

OBJECTIVES: Patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may develop end-stage lung disease requiring lung transplantation. We report the clinical course, pulmonary pathology with radiographic correlation, and outcomes after lung transplantation in three patients who developed chronic respiratory failure due to postacute sequelae of SARS-CoV-2 infection. METHODS: A retrospective histologic evaluation of explanted lungs due to coronavirus disease 2019 was performed. RESULTS: None of the patients had known prior pulmonary disease. The major pathologic findings in the lung explants were proliferative and fibrotic phases of diffuse alveolar damage, interstitial capillary neoangiogenesis, and mononuclear inflammation, specifically macrophages, with varying numbers of T and B lymphocytes. The fibrosis varied from early collagen deposition to more pronounced interstitial collagen deposition; however, pulmonary remodeling with honeycomb change was not present. Other findings included peribronchiolar metaplasia, microvascular thrombosis, recanalized thrombi in muscular arteries, and pleural adhesions. No patients had either recurrence of SARS-CoV-2 infection or allograft rejection following transplant at this time. CONCLUSIONS: The major pathologic findings in the lung explants of patients with SARS-CoV-2 infection suggest ongoing fibrosis, prominent macrophage infiltration, neoangiogenesis, and microvascular thrombosis. Characterization of pathologic findings could help develop novel management strategies.

Association of SARS-CoV-2 placental histopathology findings with maternal-fetal comorbidities and severity of COVID-19 hypoxia.

OBJECTIVE: SARS-CoV-2 is known to impact multiple organ systems, with growing data to suggest the potential for placental infection and resultant pathology. Understanding how maternal COVID-19 disease can affect placental histopathology has been limited by small study cohorts with mild disease, review by multiple pathologists, and potential confounding by maternal-fetal comorbidities that can also influence placental findings. This study aims to identify pathologic placental findings associated with COVID-19 disease and severity, as well as to distinguish them from changes related to coexisting maternal-fetal comorbidities. METHODS: This is an observational study of 61 pregnant women with confirmed SARS-CoV-2 infection who delivered and had a placental histological evaluation at NYU Langone Health between March 19, 2020 and June 30, 2020. Primary outcomes were the prevalence of placental histopathologic features and their association with maternal-fetal comorbidities and severity of COVID-19 related hypoxia. Analysis was performed using Fisher's exact test and t-test with p < 0.05 considered significant. RESULTS: Sixty-one placentas were included in the study cohort, 71% from pregnancies complicated by at least one maternal-fetal comorbidity. Twenty-five percent of placentas were small for gestational age and 77% exhibited at least one feature of maternal vascular malperfusion. None of the histopathologic features in the examined placentas were associated with the presence of any specific maternal-fetal comorbidity. Thirteen percent of the cohort required maternal respiratory support for COVID-19 related hypoxia. Villous trophoblast necrosis was associated with maternal supplemental oxygen requirement (67 vs. 33%, p = 0.04) and intubation (67 vs. 33%, p = 0.01). CONCLUSION: In pregnancies complicated by COVID-19 disease, there was a high prevalence of placental histopathologic changes identified, particularly features of maternal vascular malperfusion, which could not be attributed solely to the presence of maternal-fetal comorbidities. The significantly increased prevalence of villous trophoblast necrosis in women needing respiratory support suggests a connection to the severity of COVID-19 illness.

Biomarkers of Angiogenesis and Clinical Outcomes to Cabozantinib and Everolimus in Patients with Metastatic Renal Cell Carcinoma from the Phase III METEOR Trial.

PURPOSE: Antiangiogenic VEGF receptor (VEGFR) inhibitors are approved for metastatic clear cell renal cell carcinoma (mccRCC) and their efficacy is higher in high angiogenic tumors. As cabozantinib inhibits multiple tyrosine kinase receptors, including VEGFRs, we tested whether markers of angiogenesis, including microvascular density (MVD) and mast cell density (MCD), could predict benefit from cabozantinib versus everolimus, using RCC samples from the METEOR (NCT01865747) trial. EXPERIMENTAL DESIGN: MVD and MCD were studied in 430 patients (cabozantinib = 216, everolimus = 214) by double immunohistochemistry for CD31 (vascular marker) and tryptase (mast cell marker) coupled with automated image analysis. Results from evaluable cases (MVD = 360, MCD = 325) were correlated with progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). RESULTS: MVD was positively correlated with MCD. In the whole cohort, high MVD and high MCD were associated with longer PFS; improved PFS was most evident in patients with high levels of both MCD and MVD. Cabozantinib was associated with improved PFS, OS, and ORR compared with everolimus, irrespective of MVD levels. Cabozantinib was also associated with improved ORR compared with everolimus, irrespective of MCD levels. For PFS and OS, the treatment effect for cabozantinib versus everolimus tended to be greater in tumors with low MCD. CONCLUSIONS: High MVD and high MCD are associated with improved outcome in mccRCC but do not predict efficacy to cabozantinib versus everolimus. The high efficacy of cabozantinib in low angiogenic tumors allows us to speculate that its antitumor activity is not exclusively mediated by VEGFR inhibition.

Integrative molecular characterization of sarcomatoid and rhabdoid renal cell carcinoma.

Sarcomatoid and rhabdoid (S/R) renal cell carcinoma (RCC) are highly aggressive tumors with limited molecular and clinical characterization. Emerging evidence suggests immune checkpoint inhibitors (ICI) are particularly effective for these tumors, although the biological basis for this property is largely unknown. Here, we evaluate multiple clinical trial and real-world cohorts of S/R RCC to characterize their molecular features, clinical outcomes, and immunologic characteristics. We find that S/R RCC tumors harbor distinctive molecular features that may account for their aggressive behavior, including BAP1 mutations, CDKN2A deletions, and increased expression of MYC transcriptional programs. We show that these tumors are highly responsive to ICI and that they exhibit an immune-inflamed phenotype characterized by immune activation, increased cytotoxic immune infiltration, upregulation of antigen presentation machinery genes, and PD-L1 expression. Our findings build on prior work and shed light on the molecular drivers of aggressivity and responsiveness to ICI of S/R RCC.

Investigating the spectrum of dermatologic manifestations in COVID-19 infection in severely ill patients: A series of four cases.

COVID-19, an infectious disease caused by the novel coronavirus, was initially identified in Wuhan, China, in December 2019. By March 2020, it was declared a pandemic by the World Health Organization. Although most findings have been reported in the lungs, primarily due to catastrophic respiratory decline, other organs, including the skin, are affected. Recent reports have been published describing the clinical spectrum of COVID-19-related lesions. In addition, recent case series have described a subset of these lesions having underlying thrombotic microangiopathy with increased complement activation characterized by increased C4d deposition within the blood vessel walls. Herein, we describe a series of COVID-19-related cutaneous manifestations found at autopsy examination and their underlying histopathologic findings. Although the clinical manifestations seen in these lesions vary widely, the underlying etiology of thrombotic microangiopathy remains consistent and reproducible.

Efficacy and Safety of Nivolumab Plus Ipilimumab versus Sunitinib in First-line Treatment of Patients with Advanced Sarcomatoid Renal Cell Carcinoma.

PURPOSE: Patients with advanced renal cell carcinoma with sarcomatoid features (sRCC) have poor prognoses and suboptimal outcomes with targeted therapy. This post hoc analysis of the phase III CheckMate 214 trial analyzed the efficacy of nivolumab plus ipilimumab (NIVO+IPI) versus sunitinib in patients with sRCC. PATIENTS AND METHODS: Patients with sRCC were identified via independent central pathology review of archival tumor tissue or histologic classification per local pathology report. Patients were randomized 1:1 to receive nivolumab (3 mg/kg) plus ipilimumab (1 mg/kg) every 3 weeks (four doses) then nivolumab 3 mg/kg every 2 weeks, or sunitinib 50 mg orally every day (4 weeks; 6-week cycles). Outcomes in patients with sRCC were not prespecified. Endpoints in patients with sRCC and International Metastatic Renal Cell Carcinoma Database Consortium intermediate/poor-risk disease included overall survival (OS), progression-free survival (PFS) per independent radiology review, and objective response rate (ORR) per RECIST v1.1. Safety outcomes used descriptive statistics. RESULTS: Of 1,096 randomized patients in CheckMate 214, 139 patients with sRCC and intermediate/poor-risk disease and six with favorable-risk disease were identified. With 42 months' minimum follow-up in patients with sRCC and intermediate/poor-risk disease, median OS [95% confidence interval (CI)] favored NIVO+IPI [not reached (NR) (25.2-not estimable [NE]); n = 74] versus sunitinib [14.2 months (9.3-22.9); n = 65; HR, 0.45 (95% CI, 0.3-0.7; P = 0.0004)]; PFS benefits with NIVO+IPI were similarly observed [median 26.5 vs. 5.1 months; HR, 0.54 (95% CI, 0.33-0.86; P = 0.0093)]. Confirmed ORR was 60.8% with NIVO+IPI versus 23.1% with sunitinib, with complete response rates of 18.9% versus 3.1%, respectively. No new safety signals emerged. CONCLUSIONS: NIVO+IPI showed unprecedented long-term survival, response, and complete response benefits versus sunitinib in previously untreated patients with sRCC and intermediate/poor-risk disease, supporting the use of first-line NIVO+IPI for this population.See related commentary by Hwang et al., p. 5.

Expression of T-Cell Exhaustion Molecules and Human Endogenous Retroviruses as Predictive Biomarkers for Response to Nivolumab in Metastatic Clear Cell Renal Cell Carcinoma.

PURPOSE: We sought to validate levels of CD8+ tumor-infiltrating cells (TIC) expressing PD-1 but not TIM-3 and LAG-3 (IF biomarker; Pignon and colleagues, 2019) and to investigate human endogenous retroviruses (hERV) as predictors of response to anti-PD-1 in a randomized trial of nivolumab (nivo) versus everolimus (evero) in patients with metastatic clear cell renal cell carcinoma (mccRCC; CheckMate-025). EXPERIMENTAL DESIGN: Tumor tissues (nivo: n = 116, evero: n = 107) were analyzed by multiparametric immunofluorescence (IF) and qRT-PCR. Genomic/transcriptomic analyses were performed in a subset of samples. Clinical endpoints included objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and durable response rate (DRR, defined as complete response or partial response with a PFS ≥ 12 months). RESULTS: In the nivo (but not evero) arm, patients with high-IF biomarker density (24/116, 20.7%) had higher ORR (45.8% vs. 19.6%, P = 0.01) and DRR (33.3% vs. 14.1%, P = 0.03) and longer median PFS (9.6 vs. 3.7 months, P = 0.03) than patients with low-IF biomarker. By RNA sequencing, several inflammatory pathways (q < 0.1) and immune-related gene signature scores (q < 0.05) were enriched in the high-IF biomarker group. When combined with the IF biomarker, tumor cell (TC) PD-L1 expression (≥1%) further separated clinical outcomes in the nivo arm. ERVE-4 expression was associated with increased DRR and longer PFS in nivo-treated patients. CONCLUSIONS: High levels of CD8+ TIC expressing PD-1 but not TIM-3 and LAG-3 and ERVE-4 expression predicted response to nivo (but not to evero) in patients with mccRCC. Combination of the IF biomarker with TC PD-L1 improved its predictive value, confirming our previous findings.

SARS-CoV-2 Is Not Detected in the Cerebrospinal Fluid of Encephalopathic COVID-19 Patients.

Neurologic manifestations of the novel coronavirus SARS-CoV-2 infection have received wide attention, but the mechanisms remain uncertain. Here, we describe computational data from public domain RNA-seq datasets and cerebrospinal fluid data from adult patients with severe COVID-19 pneumonia that suggest that SARS-CoV-2 infection of the central nervous system is unlikely. We found that the mRNAs encoding the ACE2 receptor and the TMPRSS2 transmembrane serine protease, both of which are required for viral entry into host cells, are minimally expressed in the major cell types of the brain. In addition, CSF samples from 13 adult encephalopathic COVID-19 patients diagnosed with the viral infection via nasopharyngeal swab RT-PCR did not show evidence for the virus. This particular finding is robust for two reasons. First, the RT-PCR diagnostic was validated for CSF studies using stringent criteria; and second, 61% of these patients had CSF testing within 1 week of a positive nasopharyngeal diagnostic test. We propose that neurologic sequelae of COVID-19 are not due to SARS-CoV-2 meningoencephalitis and that other etiologies are more likely mechanisms.

Prognostic significance and immune correlates of CD73 expression in renal cell carcinoma.

BACKGROUND: CD73-adenosine signaling in the tumor microenvironment is immunosuppressive and may be associated with aggressive renal cell carcinoma (RCC). We investigated the prognostic significance of CD73 protein expression in RCC leveraging nephrectomy samples. We also performed a complementary analysis using The Cancer Genome Atlas (TCGA) dataset to evaluate the correlation of CD73 (ecto-5'-nucleotidase (NT5E), CD39 (ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD1)) and A2 adenosine receptor (A2AR; ADORA2A) transcript levels with markers of angiogenesis and antitumor immune response. METHODS: Patients with RCC with available archived nephrectomy samples were eligible for inclusion. Tumor CD73 protein expression was assessed by immunohistochemistry and quantified using a combined score (CS: % positive cells×intensity). Samples were categorized as CD73negative (CS=0), CD73low or CD73high (< and ≥median CS, respectively). Multivariable Cox regression analysis compared disease-free survival (DFS) and overall survival (OS) between CD73 expression groups. In the TCGA dataset, samples were categorized as low, intermediate and high NT5E, ENTPD1 and ADORA2A gene expression groups. Gene expression signatures for infiltrating immune cells, angiogenesis, myeloid inflammation, and effector T-cell response were compared between NT5E, ENTPD1 and ADORA2A expression groups. RESULTS: Among the 138 patients eligible for inclusion, 'any' CD73 expression was observed in 30% of primary tumor samples. High CD73 expression was more frequent in patients with M1 RCC (29% vs 12% M0), grade 4 tumors (27% vs 13% grade 3 vs 15% grades 1 and 2), advanced T-stage (≥T3: 22% vs T2: 19% vs T1: 12%) and tumors with sarcomatoid histology (50% vs 12%). In the M0 cohort (n=107), patients with CD73high tumor expression had significantly worse 5-year DFS (42%) and 10-year OS (22%) compared with those in the CD73negative group (DFS: 75%, adjusted HR: 2.7, 95% CI 1.3 to 5.9, p=0.01; OS: 64%, adjusted HR: 2.6, 95% CI 1.2 to 5.8, p=0.02) independent of tumor stage and grade. In the TCGA analysis, high NT5E expression was associated with significantly worse 5-year OS (p=0.008). NT5E and ENTPD1 expression correlated with higher regulatory T cell (Treg) signature, while ADORA2A expression was associated with increased Treg and angiogenesis signatures. CONCLUSIONS: High CD73 expression portends significantly worse survival outcomes independent of stage and grade. Our findings provide compelling support for targeting the immunosuppressive and proangiogenic CD73-adenosine pathway in RCC.

Mammalian SWI/SNF Complex Genomic Alterations and Immune Checkpoint Blockade in Solid Tumors.

Prior data have variably implicated the inactivation of the mammalian SWItch/Sucrose Non-Fermentable (mSWI/SNF) complex with increased tumor sensitivity to immune checkpoint inhibitors (ICI). Herein, we examined the association between mSWI/SNF variants and clinical outcomes to ICIs. We correlated somatic loss-of-function (LOF) variants in a predefined set of mSWI/SNF genes (ARID1A, ARID1B, SMARCA4, SMARCB1, PBRM1, and ARID2) with clinical outcomes in patients with cancer treated with systemic ICIs. We identified 676 patients from Dana-Farber Cancer Institute (DFCI, Boston, MA) and 848 patients from a publicly available database from Memorial Sloan Kettering Cancer Center (MSKCC, New York, NY) who met the inclusion criteria. Multivariable analyses were conducted and adjusted for available baseline factors and tumor mutational burden. Median follow-up was 19.6 (17.6-22.0) months and 28.0 (25.0-29.0) months for the DFCI and MSKCC cohorts, respectively. Seven solid tumor subtypes were examined. In the DFCI cohort, LOF variants of mSWI/SNF did not predict improved overall survival (OS), time-to-treatment failure (TTF), or disease control rate. Only patients with renal cell carcinoma with mSWI/SNF LOF showed significantly improved OS and TTF with adjusted HRs (95% confidence interval) of 0.33 (0.16-0.7) and 0.49 (0.27-0.88), respectively, and this was mostly driven by PRBM1 In the MSKCC cohort, where only OS was captured, LOF mSWI/SNF did not correlate with improved outcomes across any tumor subtype. We did not find a consistent association between mSWI/SNF LOF variants and improved clinical outcomes to ICIs, suggesting that mSWI/SNF variants should not be considered as biomarkers of response to ICIs.

Characteristics of Breast Cancer Metastasizing to Bone in a Mediterranean Population.

AIM: This study examines clinicopathological, molecular, and radiological characteristics of breast cancer metastasizing to the bone in a Mediterranean population. METHODS: Cases of breast cancer with metastasis to bone were retrieved from the pathology department archives. Descriptive statistics and bivariate inferential statistics of retrieved clinical (demographic, focality, laterality, axillary lymph node status, and metastasis-free interval), radiological (skeletal site of bone metastasis, type of bone lesion), and microscopic (grade, subtype of breast cancer, lymphovascular status, perineural status, lymph node involvement, nodal extracapsular extension, molecular subtype) data were conducted. RESULTS: Out of 123 cases analyzed, 93.5% were ductal, 90% had axillary lymph node metastasis, 60.5% were luminal A, 59.6% were osteolytic, and 54.4% had grade III. Discordance in the status of ER, PR, and HER2 between the primary breast tumor and the corresponding bone metastases was noted, with the highest rate of change reported for PR (35.7%). Significance was detected at the level of difference between the subtype of breast cancer with regards to the radiologic features where the ductal subtype was found to be mostly osteolytic while the lobular subtype was mostly either osteoblastic or mixed (p-value=0.05). The metastasis-free interval was significantly associated with the number of metastatic bone lesions (P=0.001). CONCLUSION: The significant association between metastasis-free interval and the number of metastatic bone lesions suggests that a higher interval allows more time for tumors to manifest multiple lesions. The high rate of discordance in the status of PR, ER, and HER2 was congruent with the literature highlighting the need to further investigate underlying mechanisms.

Single-cell RNA sequencing reveals compromised immune microenvironment in precursor stages of multiple myeloma.

Precursor states of Multiple Myeloma (MM) and its native tumor microenvironment need in-depth molecular characterization to better stratify and treat patients at risk. Using single-cell RNA sequencing of bone marrow cells from precursor stages, MGUS and smoldering myeloma (SMM), to full-blown MM alongside healthy donors, we demonstrate early immune changes during patient progression. We find NK cell abundance is frequently increased in early stages, and associated with altered chemokine receptor expression. As early as SMM, we show loss of GrK+ memory cytotoxic T-cells, and show their critical role in MM immunosurveillance in mouse models. Finally, we report MHC class II dysregulation in CD14+ monocytes, which results in T cell suppression in vitro. These results provide a comprehensive map of immune changes at play over the evolution of pre-malignant MM, which will help develop strategies for immune-based patient stratification.

Results of a Multicenter Phase II Study of Atezolizumab and Bevacizumab for Patients With Metastatic Renal Cell Carcinoma With Variant Histology and/or Sarcomatoid Features.

PURPOSE: In this multicenter phase II trial, we evaluated atezolizumab combined with bevacizumab in patients with advanced renal cell carcinoma (RCC) with variant histology or any RCC histology with ≥ 20% sarcomatoid differentiation. PATIENTS AND METHODS: Eligible patients may have received previous systemic therapy, excluding prior bevacizumab or checkpoint inhibitors. Patients underwent a baseline biopsy and received atezolizumab 1,200 mg and bevacizumab 15 mg/kg intravenously every 3 weeks. The primary end point was overall response rate (ORR) by RECIST version 1.1. Additional end points were progression-free survival (PFS), toxicity, biomarkers of response as determined by programmed death-ligand 1 (PD-L1) status, and on-therapy quality-of-life (QOL) metrics using the Functional Assessment of Cancer Therapy Kidney Symptom Index-19 and the Brief Fatigue Inventory. RESULTS: Sixty patients received at least 1 dose of either study agent; the majority (65%) were treatment naïve. The ORR for the overall population was 33% and 50% in patients with clear cell RCC with sarcomatoid differentiation and 26% in patients with variant histology RCC. Median PFS was 8.3 months (95% CI, 5.7 to 10.9 months). PD-L1 status was available for 36 patients; 15 (42%) had ≥ 1% expression on tumor cells. ORR in PD-L1-positive patients was 60% (n = 9) v 19% (n = 4) in PD-L1-negative patients. Eight patients (13%) developed treatment-related grade 3 toxicities. There were no treatment-related grade 4-5 toxicities. QOL was maintained throughout therapy. CONCLUSION: In this study, atezolizumab and bevacizumab demonstrated safety and resulted in objective responses in patients with variant histology RCC or RCC with ≥ 20% sarcomatoid differentiation. This regimen warrants additional exploration in patients with rare RCC, particularly those with PD-L1-positive tumors.

The KDM5A/RBP2 histone demethylase represses NOTCH signaling to sustain neuroendocrine differentiation and promote small cell lung cancer tumorigenesis.

More than 90% of small cell lung cancers (SCLCs) harbor loss-of-function mutations in the tumor suppressor gene RB1 The canonical function of the RB1 gene product, pRB, is to repress the E2F transcription factor family, but pRB also functions to regulate cellular differentiation in part through its binding to the histone demethylase KDM5A (also known as RBP2 or JARID1A). We show that KDM5A promotes SCLC proliferation and SCLC's neuroendocrine differentiation phenotype in part by sustaining expression of the neuroendocrine transcription factor ASCL1. Mechanistically, we found that KDM5A sustains ASCL1 levels and neuroendocrine differentiation by repressing NOTCH2 and NOTCH target genes. To test the role of KDM5A in SCLC tumorigenesis in vivo, we developed a CRISPR/Cas9-based mouse model of SCLC by delivering an adenovirus (or an adeno-associated virus [AAV]) that expresses Cre recombinase and sgRNAs targeting Rb1, Tp53, and Rbl2 into the lungs of Lox-Stop-Lox Cas9 mice. Coinclusion of a KDM5A sgRNA decreased SCLC tumorigenesis and metastasis, and the SCLCs that formed despite the absence of KDM5A had higher NOTCH activity compared to KDM5A+/+ SCLCs. This work establishes a role for KDM5A in SCLC tumorigenesis and suggests that KDM5 inhibitors should be explored as treatments for SCLC.

PD-L1 Expression and Clinical Outcomes to Cabozantinib, Everolimus, and Sunitinib in Patients with Metastatic Renal Cell Carcinoma: Analysis of the Randomized Clinical Trials METEOR and CABOSUN.

PURPOSE: Programmed death-ligand 1 (PD-L1) status by IHC is prognostic in metastatic renal cell carcinoma (mRCC), and its role as a potential predictive biomarker is under investigation. Using tumor tissue from the METEOR (NCT01865747) and CABOSUN (NCT01835158) clinical trials, we explored whether PD-L1 expression and the extent of the immune cell infiltrate can serve as prognostic and/or predictive biomarkers for cabozantinib and other targeted agents. EXPERIMENTAL DESIGN: IHC double staining for PD-L1 and CD45/CD163 (immune cell markers) was performed on tumor tissue from METEOR (n = 306) and CABOSUN (n = 110) clinical trials. Immune cell density and MET expression levels were also analyzed. Our primary aim was to correlate progression-free survival (PFS) by independent central review with PD-L1 status in patients treated with cabozantinib, everolimus (METEOR), or sunitinib (CABOSUN). Overall survival (OS) was also interrogated. RESULTS: Tumor cell (TC) PD-L1 expression (≥1% cutoff) was detected in 29% and 23% of tumors from patients in the METEOR and CABOSUN trials, respectively. On univariate analysis, patients with PD-L1-positive TC had poorer PFS and OS than patients with PD-L1-negative TC on both trials, independent of therapy. On multivariable analysis and when combining the two trials, the association between TC PD-L1 expression and OS was statistically significant for all patients (P = 0.034) and for patients treated with cabozantinib only (P = 0.038). Cabozantinib was associated with improved PFS (HR < 0.70) and OS (HR < 0.85) compared with everolimus and sunitinib irrespective of PD-L1 expression. CONCLUSIONS: Higher PD-L1 expression results in worse clinical outcomes in mRCC treated with targeted therapy. Furthermore, PD-L1 expression is not predictive of response to cabozantinib therapy.

irRECIST for the Evaluation of Candidate Biomarkers of Response to Nivolumab in Metastatic Clear Cell Renal Cell Carcinoma: Analysis of a Phase II Prospective Clinical Trial.

PURPOSE: Immune-related RECIST (irRECIST) were designed to capture atypical responses seen with immunotherapy. We hypothesized that, in patients with metastatic clear cell renal cell carcinoma (mccRCC), candidate biomarkers for nivolumab response would show improved association with clinical endpoints capturing atypical responders (irRECIST) compared with standard clinical endpoints (RECISTv1.1). EXPERIMENTAL DESIGN: Endpoints based on RECISTv1.1 [objective response rate (ORR)/progression-free survival (PFS)] or irRECIST [immune-related ORR (irORR)/immune-related PFS (irPFS)] were compared in patients enrolled in the CheckMate-010 trial. Pretreatment tumors were analyzed by PD-L1 and PD-L2 IHC, and by multiplex immunofluorescence for CD8, PD-1, TIM-3, and LAG-3. T-cell activation signatures were assessed by RNA sequencing. RESULTS: Median irPFS was significantly longer than median PFS. irORR was not significantly different from ORR, but immune-related progressive disease (irPD) rate was significantly lower than progressive disease (PD) rate. Tumor cell (TC) PD-L1 expression was not associated with PFS or ORR, but patients with TC PD-L1 ≥1% had longer median irPFS and higher irORR. High percentage of CD8+ tumor-infiltrating cells (TIC) that are PD-1+TIM-3-LAG-3- (% CD8+PD-1+TIM-3-LAG-3- TIC) correlated with high levels of T-cell activation and was associated with longer median irPFS and higher irORR. Notably, combination of TC PD-L1 expression with % CD8+PD-1+TIM-3-LAG-3- TIC identified three groups of patients for which irPFS and irORR were significantly different. CONCLUSIONS: Atypical responders to nivolumab were identified in the CheckMate-010 trial. We observed improved association of candidate biomarkers for nivolumab response with endpoints defined by irRECIST compared with RECISTv1.1. TC PD-L1 expression in combination with PD-1 expression on CD8+ TIC may predict outcome on nivolumab in mccRCC.