Comprehensive Analysis of Hypermutation in Human Cancer.

We present an extensive assessment of mutation burden through sequencing analysis of >81,000 tumors from pediatric and adult patients, including tumors with hypermutation caused by chemotherapy, carcinogens, or germline alterations. Hypermutation was detected in tumor types not previously associated with high mutation burden. Replication repair deficiency was a major contributing factor. We uncovered new driver mutations in the replication-repair-associated DNA polymerases and a distinct impact of microsatellite instability and replication repair deficiency on the scale of mutation load. Unbiased clustering, based on mutational context, revealed clinically relevant subgroups regardless of the tumors' tissue of origin, highlighting similarities in evolutionary dynamics leading to hypermutation. Mutagens, such as UV light, were implicated in unexpected cancers, including sarcomas and lung tumors. The order of mutational signatures identified previous treatment and germline replication repair deficiency, which improved management of patients and families. These data will inform tumor classification, genetic testing, and clinical trial design.

Niraparib with Abiraterone Acetate and Prednisone for Metastatic Castration-Resistant Prostate Cancer: Phase II QUEST Study Results.

Niraparib (NIRA) is a highly selective inhibitor of poly (adenosine diphosphate-ribose) polymerase, PARP1 and PARP2, which play a role in DNA repair. The phase II QUEST study evaluated NIRA combinations in patients with metastatic castration-resistant prostate cancer who were positive for homologous recombination repair gene alterations and had progressed on 1 prior line of novel androgen receptor-targeted therapy. Results from the combination of NIRA with abiraterone acetate plus prednisone, which disrupts androgen axis signaling through inhibition of CYP17, showed promising efficacy and a manageable safety profile in this patient population.

Niraparib in patients with metastatic castration-resistant prostate cancer and DNA repair gene defects (GALAHAD): a multicentre, open-label, phase 2 trial.

BACKGROUND: Metastatic castration-resistant prostate cancers are enriched for DNA repair gene defects (DRDs) that can be susceptible to synthetic lethality through inhibition of PARP proteins. We evaluated the anti-tumour activity and safety of the PARP inhibitor niraparib in patients with metastatic castration-resistant prostate cancers and DRDs who progressed on previous treatment with an androgen signalling inhibitor and a taxane. METHODS: In this multicentre, open-label, single-arm, phase 2 study, patients aged at least 18 years with histologically confirmed metastatic castration-resistant prostate cancer (mixed histology accepted, with the exception of the small cell pure phenotype) and DRDs (assessed in blood, tumour tissue, or saliva), with progression on a previous next-generation androgen signalling inhibitor and a taxane per Response Evaluation Criteria in Solid Tumors 1.1 or Prostate Cancer Working Group 3 criteria and an Eastern Cooperative Oncology Group performance status of 0-2, were eligible. Enrolled patients received niraparib 300 mg orally once daily until treatment discontinuation, death, or study termination. For the final study analysis, all patients who received at least one dose of study drug were included in the safety analysis population; patients with germline pathogenic or somatic biallelic pathogenic alterations in BRCA1 or BRCA2 (BRCA cohort) or biallelic alterations in other prespecified DRDs (non-BRCA cohort) were included in the efficacy analysis population. The primary endpoint was objective response rate in patients with BRCA alterations and measurable disease (measurable BRCA cohort). This study is registered with ClinicalTrials.gov, NCT02854436. FINDINGS: Between Sept 28, 2016, and June 26, 2020, 289 patients were enrolled, of whom 182 (63%) had received three or more systemic therapies for prostate cancer. 223 (77%) of 289 patients were included in the overall efficacy analysis population, which included BRCA (n=142) and non-BRCA (n=81) cohorts. At final analysis, with a median follow-up of 10·0 months (IQR 6·6-13·3), the objective response rate in the measurable BRCA cohort (n=76) was 34·2% (95% CI 23·7-46·0). In the safety analysis population, the most common treatment-emergent adverse events of any grade were nausea (169 [58%] of 289), anaemia (156 [54%]), and vomiting (111 [38%]); the most common grade 3 or worse events were haematological (anaemia in 95 [33%] of 289; thrombocytopenia in 47 [16%]; and neutropenia in 28 [10%]). Of 134 (46%) of 289 patients with at least one serious treatment-emergent adverse event, the most common were also haematological (thrombocytopenia in 17 [6%] and anaemia in 13 [4%]). Two adverse events with fatal outcome (one patient with urosepsis in the BRCA cohort and one patient with sepsis in the non-BRCA cohort) were deemed possibly related to niraparib treatment. INTERPRETATION: Niraparib is tolerable and shows anti-tumour activity in heavily pretreated patients with metastatic castration-resistant prostate cancer and DRDs, particularly in those with BRCA alterations. FUNDING: Janssen Research & Development.

Germline-driven replication repair-deficient high-grade gliomas exhibit unique hypomethylation patterns.

Replication repair deficiency (RRD) leading to hypermutation is an important driving mechanism of high-grade glioma (HGG) occurring predominantly in the context of germline mutations in RRD-associated genes. Although HGG presents specific patterns of DNA methylation corresponding to oncogenic mutations, this has not been well studied in replication repair-deficient tumors. We analyzed 51 HGG arising in the background of gene mutations in RRD utilizing either 450 k or 850 k methylation arrays. These were compared with HGG not known to be from patients with RRD. RRD HGG harboring secondary mutations in glioma genes such as IDH1 and H3F3A displayed a methylation pattern corresponding to these methylation subgroups. Strikingly, RRD HGG lacking these known secondary mutations clustered together with an incompletely described group of HGG previously labeled "Wild type-C" or "Paediatric RTK 1". Independent analysis of two comparator HGG cohorts showed that other RRD/hypermutant tumors clustered within these subgroups, suggesting that undiagnosed RRD may be driving some HGG clustering in this location. RRD HGG displayed a unique CpG Island Demethylator Phenotype in contrast to the CpG Island Methylator Phenotype described in other cancers. Hypomethylation was enriched at gene promoters with prominent demethylation in genes and pathways critical to cellular survival including cell cycle, gene expression, cellular metabolism, and organization. These data suggest that methylation arrays may provide diagnostic information for the detection of RRD HGG. Furthermore, our findings highlight the unique natural selection pressures in these highly dysregulated, hypermutant cancers and provide the novel impact of hypermutation and RRD on the cancer epigenome.

Delayed diagnosis of fatal pneumonic canine plague: clinical and pathologic features in two naturally infected Colorado dogs.

BACKGROUND: Plague caused by Yersinia pestis is a highly infectious and potentially fatal zoonotic disease that can be spread by wild and domestic animals. In endemic areas of the northern hemisphere plague typically cycles from March to October, when flea vectors are active. Clinical forms of disease include bubonic, septicemic, and pneumonic plague. All clinical forms are uncommon in dogs and the pneumonic form is exceedingly rare. CASE PRESENTATION: Two mixed breed young-adult male domestic dogs presented to Colorado veterinarians with fever and vague signs that progressed to hemoptysis within 24 h. Case 1 presented in June 2014, while Case 2 occurred in December 2017. Thoracic radiography of Case 1 and 2 revealed right dorsal and right accessory lobe consolidation, respectively. In Case 1 initial differential diagnoses included pulmonary contusion due to trauma or diphacinone toxicosis. Case 1 was euthanized ~ 24 h post presentation due to progressive dyspnea and hemoptysis. Plague was confirmed 9 days later, after the dog's owner was hospitalized with pneumonia. Case 2 was treated as foreign body/aspiration pneumonia and underwent lung lobectomy at a veterinary teaching hospital. Case 2 was euthanized after 5 days of hospitalization when bacterial culture of the excised lobe yielded Yersinia pestis. Both dogs had severe diffuse necrohemorrhagic and suppurative pneumonia at post mortem examination. CONCLUSIONS: Both dogs were misdiagnosed due to the atypical lobar presentation of an extremely rare form of plague in a species that infrequently succumbs to clinical disease. Presentation outside of the typical transmission period of plague was also a factor leading to delayed diagnosis in Case 2. Erroneous identification by automated bacterial identification systems was problematic in both cases. In endemic areas, plague should be ruled out early in febrile dogs with acute respiratory signs, hemoptysis, lobar or diffuse pathology, and potential for exposure, regardless of season. Seasonal and geographic distributions of plague may shift with climate change, so vigilance by primary care veterinarians is warranted. Timely submission of samples to a veterinary diagnostic laboratory could expedite accurate diagnosis and reduce potential for human and domestic animal exposure.

Contrast-enhanced 3-dimensional Fluid-attenuated Inversion Recovery Sequences Have Greater Sensitivity for Detection of Leptomeningeal Metastases in Pediatric Brain Tumors Compared With Conventional Spoiled Gradient Echo Sequences.

Postcontrast 3-dimensional fluid-attenuated inversion recovery (3D-FLAIR) sequences have reduced vascular and flow-related artifacts and high sensitivity to low gadolinium concentrations. We compared the performance of postcontrast spoiled gradient echo images to 3D-FLAIR in the detection of leptomeningeal metastases in 47 pediatric patients with brain tumors. We found 10 cases with more leptomeningeal signal abnormalities on 3D-FLAIR. Overall there were significantly more lesions on 3D-FLAIR than spoiled gradient echo sequences. We believe the increased detection of leptomeningeal signal abnormality is due to increased sensitivity for low concentrations of gadolinium in regions of early blood brain barrier breakdown. Our study was limited by the lack of leptomeningeal metastases in cerebrospinal fluid sampling. We plan to conduct future studies which will determine whether the time-based concentration of gadolinium affects the performance and results. Future studies will also require more cases of pathology-proven leptomeningeal disease.

Antigen-specific immunoreactivity and clinical outcome following vaccination with glioma-associated antigen peptides in children with recurrent high-grade gliomas: results of a pilot study.

Recurrent high-grade gliomas (HGGs) of childhood have an exceedingly poor prognosis with current therapies. Accordingly, new treatment approaches are needed. We initiated a pilot trial of vaccinations with peptide epitopes derived from glioma-associated antigens (GAAs) overexpressed in these tumors in HLA-A2+ children with recurrent HGG that had progressed after prior treatments. Peptide epitopes for three GAAs (EphA2, IL13Rα2, survivin), emulsified in Montanide-ISA-51, were administered subcutaneously adjacent to intramuscular injections of poly-ICLC every 3 weeks for 8 courses, followed by booster vaccines every 6 weeks. Primary endpoints were safety and T-cell responses against the GAA epitopes, assessed by enzyme-linked immunosorbent spot (ELISPOT) analysis. Treatment response was evaluated clinically and by magnetic resonance imaging. Twelve children were enrolled, 6 with glioblastoma, 5 with anaplastic astrocytoma, and one with malignant gliomatosis cerebri. No dose-limiting non-CNS toxicity was encountered. ELISPOT analysis, in ten children, showed GAA responses in 9: to IL13Rα2 in 4, EphA2 in 9, and survivin in 3. One child had presumed symptomatic pseudoprogression, discontinued vaccine therapy, and responded to subsequent treatment. One other child had a partial response that persisted throughout 2 years of vaccine therapy, and continues at >39 months. Median progression-free survival (PFS) from the start of vaccination was 4.1 months and median overall survival (OS) was 12.9 months. 6-month PFS and OS were 33 and 73 %, respectively. GAA peptide vaccination in children with recurrent malignant gliomas is generally well tolerated, and has preliminary evidence of immunological and modest clinical activity.

Transcriptional Profiling Identifies the Signaling Axes of IGF and Transforming Growth Factor-b as Involved in the Pathogenesis of Osteosarcoma.

BACKGROUND: Osteosarcoma is the most common primary bone tumor in adolescents associated with skeletal development. The molecular pathogenesis of osteosarcoma has not been completely determined, although many molecular alterations have been found in human osteosarcomas and cell lines. QUESTIONS/PURPOSES: We questioned whether (1) we could identify gene expression in osteosarcoma specimens that differs from normal osteoblasts and mesenchymal stem cells and (2) this would provide clues to the molecular pathogenesis of osteosarcoma? METHODS: The whole-genome transcriptional profiles of osteosarcomas, including two primary biopsy specimens, two cell lines, two xenografts derived from patient specimens, and one from normal osteoblasts and from mesenchymal stem cells, respectively, were quantitatively measured using serial analysis of gene expression. A statistical enrichment was performed, which selects the common genes altered in each of the osteosarcomas compared with each of the normal counterparts independently. RESULTS: Sixty (92%) of 65 total genes that were at least twofold downregulated in osteosarcoma compared with osteoblasts and mesenchymal stem cells, could be classified in four categories: (1) seven genes in the insulin­like growth factor (IGF) signaling axis, including three of the IGF-binding proteins (IGFBP) and three of the IGFBPrelated proteins (IGFBPrP); (2) eight genes in the transforming growth factor-b (TGF-b)/bone morphogenetic protein (BMP) signaling cascade; (3) 39 genes encoding cytoskeleton and extracellular matrix proteins that are regulated by TGF-b/BMPs; and (4) six genes involved in cell cycle regulation, including tumor suppressors TP63 and p21. CONCLUSIONS: Based on these transcriptional profiles, a coordinated theme of clustered gene deregulation in osteosarcoma has emerged. Cell proliferation driven by the IGF axes during bone growth is unrestrained owing to downregulation of IGFBPs and cell cycle regulators. Tumor cells may be maintained in an undifferentiated state secondary to impaired TGF-b/BMP signaling. This wellpreserved pattern suggests that the alterations in the signaling axes of IGF-1 and TGF-b, in concert with cell cycle regulators, may be an important pathogenic basis of osteosarcoma. CLINIC RELEVANCE: This study provides a possible molecular basis of pathogenesis of osteosarcoma. This may help to develop new therapeutic targets and strategy for this disease. Preclinical and subsequently clinical testing of inhibitors of the IGF-1 and TGF pathways would be warranted.

A clinicopathologic study of diencephalic pediatric low-grade gliomas with BRAF V600 mutation.

Among brain tumors, the BRAF (V600E) mutation is frequently associated with pleomorphic xanthoastrocytomas (PXAs) and gangliogliomas (GGs). This oncogenic mutation is also detected in ~5 % of other pediatric low-grade gliomas (LGGs) including pilocytic astrocytomas (PAs) and diffuse astrocytomas. In the current multi-institutional study of 56 non-PXA/non-GG diencephalic pediatric LGGs, the BRAF (V600) mutation rate is 36 %. V600-mutant tumors demonstrate a predilection for infants and young children (

Outbreak of Human Pneumonic Plague with Dog-to-Human and Possible Human-to-Human Transmission--Colorado, June-July 2014.

On July 8, 2014, the Colorado Department of Public Health and Environment (CDPHE) laboratory identified Yersinia pestis, the bacterium that causes plague, in a blood specimen collected from a man (patient A) hospitalized with pneumonia. The organism had been previously misidentified as Pseudomonas luteola by an automated system in the hospital laboratory. An investigation led by Tri-County Health Department (TCHD) revealed that patient A's dog had died recently with hemoptysis. Three other persons who had contact with the dog, one of whom also had contact with patient A, were ill with fever and respiratory symptoms, including two with radiographic evidence of pneumonia. Specimens from the dog and all three human contacts yielded evidence of acute Y. pestis infection. One of the pneumonia cases might have resulted through human-to-human transmission from patient A, which would be the first such event reported in the United States since 1924. This outbreak highlights 1) the need to consider plague in the differential diagnosis of ill domestic animals, including dogs, in areas where plague is endemic; 2) the limitations of automated diagnostic systems for identifying rare bacteria such as Y. pestis; and 3) the potential for milder plague illness in patients taking antimicrobial agents. Hospital laboratorians should be aware of the limitations of automated identification systems, and clinicians should suspect plague in patients with clinically compatible symptoms from whom P. luteola is isolated.

Congenital localized cutaneous Langerhans cell histiocytosis in a Holstein calf.

Distinct solitary dermal nodules, either covered by an alopecic, or sometimes ulcerated, epidermis, were noticed on the head of a stillborn Holstein calf. The head was submitted for autopsy, and the nodules were found to consist of homogeneous, diffuse pale-yellow, soft-tissue masses with distinct margins that elevated the epidermis above the adjacent skin. Histologically, the dermal nodules were well-delineated on the deep margin approaching the cutaneous muscle and consisted of perivascular neoplastic infiltrates of round cells that in some places coalesced into sheets that extended into the dermis and subcutis. Neoplastic cells separated adnexa and collagen. Immunohistochemistry revealed intense tumor cell expression of vimentin, Iba1, E-cadherin, and CD204; expression of CD18 was faint. The masses were diagnosed as Langerhans cell histiocytosis. Congenital cutaneous Langerhans cell histiocytosis has not been reported previously in cattle, to our knowledge, and should be included in the differential diagnosis of congenital nodular skin lesions.

Mucosal transmission and pathogenesis of chronic wasting disease in ferrets.

Chronic wasting disease (CWD) of cervids is almost certainly transmitted by mucosal contact with the causative prion, whether by direct (animal-to-animal) or indirect (environmental) means. Yet the sites and mechanisms of prion entry remain to be further understood. This study sought to extend this understanding by demonstrating that ferrets exposed to CWD via several mucosal routes developed infection, CWD prion protein (PrP(CWD)) amplification in lymphoid tissues, neural invasion and florid transmissible spongiform encephalopathy lesions resembling those in native cervid hosts. The ferrets developed extensive PrP(CWD) accumulation in the nervous system, retina and olfactory epithelium, with lesser deposition in tongue, muscle, salivary gland and the vomeronasal organ. PrP(CWD) accumulation in mucosal sites, including upper respiratory tract epithelium, olfactory epithelium and intestinal Peyer's patches, make the shedding of prions by infected ferrets plausible. It was also observed that regionally targeted exposure of the nasopharyngeal mucosa resulted in an increased attack rate when compared with oral exposure. The latter finding suggests that nasal exposure enhances permissiveness to CWD infection. The ferret model has further potential for investigation of portals for initiation of CWD infection.

Evaluation of a modified subchondroplasty technique in an equine full-thickness cartilage defect model: a pilot study.

OBJECTIVE: To perform a pilot study with the intent of assessing the feasibility of a modified subchondroplasty (mSCP) technique in a validated preclinical equine model of full-thickness articular cartilage loss and evaluate the short-term patient response to the injected materials. ANIMALS: 3 adult horses. PROCEDURES: Two 15-mm-diameter full-thickness cartilage defects were created on the medial trochlear ridge of each femur. Defects were treated with microfracture and then filled by 1 of 4 techniques: (1) autologous fibrin graft (FG) via subchondral injection of fibrin glue (FG), (2) autologous fibrin graft via direct injection of FG, (3) subchondral injection of a calcium phosphate bone substitute material (BSM) with direct injection of FG, and (4) untreated control. Horses were euthanized after 2 weeks. Patient response was evaluated via serial lameness examination, radiography, magnetic resonance imaging, computed tomography, gross evaluation, microcomputed tomography, and histopathology. RESULTS: All treatments were successfully administered. The injected material perfused through the underlying bone into the respective defects without adversely affecting the surrounding bone and articular cartilage. Increased new bone formation was seen at the margins of the trabecular spaces containing BSM. There was no treatment effect on the amount or composition of tissue within defects. CLINICAL RELEVANCE: The mSCP technique was a simple, well-tolerated technique in this equine articular cartilage defect model without significant adverse effects to host tissues after 2 weeks. Larger studies with long-term follow-ups are warranted.

Health-related quality of life in GALAHAD: A multicenter, open-label, phase 2 study of niraparib for patients with metastatic castration-resistant prostate cancer and DNA-repair gene defects.

BACKGROUND: Niraparib is a highly selective poly (adenosine diphosphateribose) polymerase-1 and poly (adenosine diphosphate-ribose) polymerase-2 inhibitor indicated for select patients with ovarian, fallopian tube, and primary peritoneal cancer. The phase 2 GALAHAD trial (NCT02854436) demonstrated that niraparib monotherapy is tolerable and efficacious in patients with metastatic castration-resistant prostate cancer (mCRPC) and homologous recombination repair (HRR) gene alterations, particularly those with breast cancer gene (BRCA) alterations who had progressed on prior androgen signaling inhibitor therapy and taxane-based chemotherapy. OBJECTIVE: To report the prespecified patient-reported outcomes analysis from GALAHAD. METHODS: Eligible patients with alterations to BRCA1 and/or BRCA2 (BRCA cohort) and with pathogenic alterations in other HRR genes (other HRR cohort) were enrolled and received niraparib 300 mg once daily. Patient-reported outcome instruments included the Functional Assessment of Cancer Therapy-Prostate and the Brief Pain Inventory-Short Form. Changes from baseline were compared using a mixed-effect model for repeated measures. RESULTS: On average, health-related quality of life (HRQoL) improved in the BRCA cohort by cycle 3 (mean change = 6.03; 95% CI = 2.76-9.29) and was maintained above baseline until cycle 10 (mean change = 2.84; 95% CI = -1.95 to 7.63), whereas the other HRR cohort showed no early change in HRQoL from baseline (mean change = -0.07; 95% CI = -4.69 to 4.55) and declined by cycle 10 (mean change = -5.10; 95% CI = -15.3 to 5.06). Median time to deterioration in pain intensity and pain interference could not be estimated in either cohort. CONCLUSIONS: Patients with advanced mCRPC and BRCA alterations treated with niraparib experienced more meaningful improvement in overall HRQoL, pain intensity, and pain interference compared with those with other HRR alterations. In this population of castrate, heavily pretreated patients with mCRPC and HRR alterations, stabilization, and improvement in HRQoL may be relevant to consider when making treatment decisions. DISCLOSURES: This work was supported by Janssen Research & Development, LLC (no grant number). Dr Smith has received grants and personal fees from Bayer, Amgen, Janssen, and Lilly; and has received personal fees from Astellas Pharma, Novartis, and Pfizer. Dr Sandhu has received grants from Amgen, Endocyte, and Genentech; has received grants and personal fees from AstraZeneca and Merck; and has received personal fees from Bristol Myers Squibb and Merck Serono. Dr George has received personal fees from the American Association for Cancer Research, Axess Oncology, Capio Biosciences, Constellation Pharma, EMD Serono, Flatiron, Ipsen, Merck Sharp & Dohme, Michael J. Hennessey Association, Millennium Medical Publishing, Modra Pharma, Myovant Sciences, Inc., NCI Genitourinary, Nektar Therapeutics, Physician Education Resource, Propella TX, RevHealth, LLC, and UroGPO; has received grants and personal fees from Astellas Pharma, AstraZeneca, Bristol Myers Squibb, and Pfizer; has received personal fees and nonfinancial support from Bayer and UroToday; has received grants from Calithera and Novartis; and has received grants, personal fees, and nonfinancial support from Exelixis, Inc., Sanofi, and Janssen Pharma. Dr Chi has received grants from Janssen during the conduct of the study; has received grants and personal fees from AstraZeneca, Bayer, Astellas Pharma, Novartis, Pfizer, POINT Biopharma, Roche, and Sanofi; and has received personal fees from Daiichi Sankyo, Merck, and Bristol Myers Squibb. Dr Saad has received grants, personal fees, and nonfinancial support from Janssen during the conduct of the study; and has received grants, personal fees, and nonfinancial support from AstraZeneca, Astellas Pharma, Pfizer, Bayer, Myovant, Sanofi, and Novartis. Dr Thiery-Vuillemin has received grants, personal fees, and nonfinancial support from Pfizer; has received personal fees and nonfinancial support from AstraZeneca, Janssen, Ipsen, Roche/Genentech, Merck Sharp & Dohme, and Astellas Pharma; and has received personal fees from Sanofi, Novartis, and Bristol Myers Squibb. Dr Olmos has received grants, personal fees, and nonfinancial support from AstraZeneca, Bayer, Janssen, and Pfizer; has received personal fees from Clovis, Daiichi Sankyo, and Merck Sharp & Dohme; and has received nonfinancial support from Astellas Pharma, F. Hoffman-LaRoche, Genentech, and Ipsen. Dr Danila has received research support from the US Department of Defense, the American Society of Clinical Oncology, the Prostate Cancer Foundation, Stand Up to Cancer, Janssen Research & Development, Astellas Pharma, Medivation, Agensys, Genentech, and CreaTV. Dr Gafanov has received grants from Janssen during the conduct of the study. Dr Castro has received grants from Janssen during the conduct of the study; has received grants and personal fees from Janssen, Bayer, AstraZeneca, and Pfizer; and has received personal fees from Astellas Pharma, Merck Sharp & Dohme, Roche, and Clovis. Dr Moon has received research funding from SeaGen, HuyaBio, Janssen, BMS, Aveo, Xencor, and has received personal fees from Axess Oncology, MJH, EMD Serono, and Pfizer. Dr Joshua has received nonfinancial support from Janssen; consulted or served in an advisory role for Neoleukin, Janssen Oncology, Ipsen, AstraZeneca, Sanofi, Noxopharm, IQvia, Pfizer, Novartis, Bristol Myers Squibb, Merck Serono, and Eisai; and received research funding from Bristol Myers Squibb, Janssen Oncology, Merck Sharp & Dohme, Mayne Pharma, Roche/Genentech, Bayer, MacroGenics, Lilly, Pfizer, AstraZeneca, and Corvus Pharmaceuticals. Drs Mason, Liu, Bevans, Lopez-Gitlitz, and Francis and Mr Espina are employees of Janssen Research & Development. Dr Mason owns stocks with Janssen. Dr Fizazi has participated in advisory boards and talks for Amgen, Astellas, AstraZeneca, Bayer, Clovis, Daiichi Sankyo, Janssen, MSD, Novartis/AAA, Pfizer, and Sanofi, with honoraria to his institution (Institut Gustave Roussy); has participated in advisory boards for, with personal honoraria from, Arvinas, CureVac, MacroGenics, and Orion. Study registration number: NCT02854436.

Niraparib and Abiraterone Acetate for Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: Metastatic castration-resistant prostate cancer (mCRPC) remains a lethal disease with current standard-of-care therapies. Homologous recombination repair (HRR) gene alterations, including BRCA1/2 alterations, can sensitize cancer cells to poly (ADP-ribose) polymerase inhibition, which may improve outcomes in treatment-naïve mCRPC when combined with androgen receptor signaling inhibition. METHODS: MAGNITUDE (ClinicalTrials.gov identifier: NCT03748641) is a phase III, randomized, double-blinded study that evaluates niraparib and abiraterone acetate plus prednisone (niraparib + AAP) in patients with (HRR+, n = 423) or without (HRR-, n = 247) HRR-associated gene alterations, as prospectively determined by tissue/plasma-based assays. Patients were assigned 1:1 to receive niraparib + AAP or placebo + AAP. The primary end point, radiographic progression-free survival (rPFS) assessed by central review, was evaluated first in the BRCA1/2 subgroup and then in the full HRR+ cohort, with secondary end points analyzed for the full HRR+ cohort if rPFS was statistically significant. A futility analysis was preplanned in the HRR- cohort. RESULTS: Median rPFS in the BRCA1/2 subgroup was significantly longer in the niraparib + AAP group compared with the placebo + AAP group (16.6 v 10.9 months; hazard ratio [HR], 0.53; 95% CI, 0.36 to 0.79; P = .001). In the overall HRR+ cohort, rPFS was significantly longer in the niraparib + AAP group compared with the placebo + AAP group (16.5 v 13.7 months; HR, 0.73; 95% CI, 0.56 to 0.96; P = .022). These findings were supported by improvement in the secondary end points of time to symptomatic progression and time to initiation of cytotoxic chemotherapy. In the HRR- cohort, futility was declared per the prespecified criteria. Treatment with niraparib + AAP was tolerable, with anemia and hypertension as the most reported grade ≥ 3 adverse events. CONCLUSION: Combination treatment with niraparib + AAP significantly lengthened rPFS in patients with HRR+ mCRPC compared with standard-of-care AAP.[Media: see text].

Evidence for distinct chronic wasting disease (CWD) strains in experimental CWD in ferrets.

Chronic wasting disease (CWD) is an evolving prion disease of cervids (deer, elk and moose) that has been recognized in North America and Korea. Infection of non-cervid reservoir or transport species in nature is not reported. However, the ferret (Mustela putorius furo) is susceptible to CWD after experimental inoculation. Here, we report that infection of ferrets with either of two ferret CWD isolates by various routes of exposure has revealed biologically distinct strain-like properties distinguished by different clinical progression and survival period. The isolates of ferret CWD were also differentiated by the distribution of the infectious prion protein (PrP(CWD)) in the brain and periphery, and by the proteinase K sensitivity of PrP(CWD). These findings suggest that diversity in prion conformers exists in CWD-infected cervids.

Chronic wasting disease prion trafficking via the autonomic nervous system.

Chronic wasting disease (CWD) is a fatal spongiform encephalopathy that is efficiently transmitted among members of the mammalian family Cervidae, including deer, elk, and moose. Typical of prion diseases, CWD is characterized by the conversion of the native protease-sensitive protein PrP(C) to a protease-resistant isoform, denoted PrP(RES). In native species, spread of the disease likely results from the ingestion of prion-containing excreta, including urine, saliva, or feces. Although cervid prion protein-expressing transgenic [Tg(CerPrP)] mice have been shown to be effective surrogates of natural CWD, uncertainties remain regarding the mechanisms by which CWD prions traffic in vivo, including the manner by which CWD prions traffic from the gastrointestinal tract to the central nervous system. We used elk prion protein-expressing transgenic [Tg(CerPrP-E)] mice, infected by three different routes of inoculation, and tissue-based IHC to elucidate that centripetal and centrifugal CWD prion transit pathways involve cells and fibers of the autonomic nervous systems, including the enteric nervous system and central autonomic network. Moreover, we identified CWD PrP(RES) associated with the cell bodies and processes of enteric glial cells within the enteric nervous system of CWD-infected Tg(CerPrP-E) mice. The present findings demonstrate the importance of the peripheral and central autonomic networks in CWD neuroinvasion and neuropathogenesis and suggest that enteroglial cells may facilitate the shedding of prions via the intestinal tract.

Safety and preliminary immunogenicity of JNJ-64041809, a live-attenuated, double-deleted Listeria monocytogenes-based immunotherapy, in metastatic castration-resistant prostate cancer.

BACKGROUND: The safety and immunogenicity of JNJ-64041809 (JNJ-809), a live-attenuated, double-deleted Listeria monocytogenes (LADD Lm)-based immunotherapy targeting 4 relevant prostate cancer antigens, was evaluated in a phase 1 study in patients with metastatic castration-resistant prostate cancer (mCRPC). METHODS: Men with progressive mCRPC who had received ≥2 prior approved therapies were enrolled. Primary study objectives were to determine the recommended phase 2 dose (RP2D) and to evaluate the safety and immunogenicity of JNJ-809. RESULTS: A total of 26 patients received JNJ-809 (1 × 108 CFU (n = 6); 1 × 109 CFU (n = 20)). No dose-limiting toxicities were reported, and 1 × 109 CFU was selected as the RP2D. The most common adverse events (AEs) reported were chills (92%), pyrexia (81%), and fatigue (62%). The most frequent grade ≥3 AEs were lymphopenia (27%) and hypertension (23%). Serious AEs were reported in 27% of patients including 1 patient with grade 3 intestinal obstruction. JNJ-809 transiently induced peripheral cytokines, including interferon-γ, interleukin-10, and tumor necrosis factor-α. Of the 7 patients evaluable for T cell responses at the 1 × 109 CFU dose, evidence of post-treatment antigenic responses were observed in 6 to the Listeria antigen listeriolysin O and in 5 to ≥1 of the 4 encoded tumor antigens. Best overall response was stable disease in 13/25 response-evaluable patients. The study was terminated early as data collected were considered sufficient to evaluate safety and immunogenicity. CONCLUSIONS: JNJ-809 has manageable safety consistent with other LADD Lm-based therapies. Limited antigen-specific immune responses were observed, which did not translate into objective clinical responses.

Genomic predictors of response to PD-1 inhibition in children with germline DNA replication repair deficiency.

Cancers arising from germline DNA mismatch repair deficiency or polymerase proofreading deficiency (MMRD and PPD) in children harbour the highest mutational and microsatellite insertion-deletion (MS-indel) burden in humans. MMRD and PPD cancers are commonly lethal due to the inherent resistance to chemo-irradiation. Although immune checkpoint inhibitors (ICIs) have failed to benefit children in previous studies, we hypothesized that hypermutation caused by MMRD and PPD will improve outcomes following ICI treatment in these patients. Using an international consortium registry study, we report on the ICI treatment of 45 progressive or recurrent tumors from 38 patients. Durable objective responses were observed in most patients, culminating in a 3 year survival of 41.4%. High mutation burden predicted response for ultra-hypermutant cancers (>100 mutations per Mb) enriched for combined MMRD + PPD, while MS-indels predicted response in MMRD tumors with lower mutation burden (10-100 mutations per Mb). Furthermore, both mechanisms were associated with increased immune infiltration even in 'immunologically cold' tumors such as gliomas, contributing to the favorable response. Pseudo-progression (flare) was common and was associated with immune activation in the tumor microenvironment and systemically. Furthermore, patients with flare who continued ICI treatment achieved durable responses. This study demonstrates improved survival for patients with tumors not previously known to respond to ICI treatment, including central nervous system and synchronous cancers, and identifies the dual roles of mutation burden and MS-indels in predicting sustained response to immunotherapy.

B cells and platelets harbor prion infectivity in the blood of deer infected with chronic wasting disease.

Substantial evidence for prion transmission via blood transfusion exists for many transmissible spongiform encephalopathy (TSE) diseases. Determining which cell phenotype(s) is responsible for trafficking infectivity has important implications for our understanding of the dissemination of prions, as well as their detection and elimination from blood products. We used bioassay studies of native white-tailed deer and transgenic cervidized mice to determine (i) if chronic wasting disease (CWD) blood infectivity is associated with the cellular versus the cell-free/plasma fraction of blood and (ii) in particular if B-cell (MAb 2-104(+)), platelet (CD41/61(+)), or CD14(+) monocyte blood cell phenotypes harbor infectious prions. All four deer transfused with the blood mononuclear cell fraction from CWD(+) donor deer became PrP(CWD) positive by 19 months postinoculation, whereas none of the four deer inoculated with cell-free plasma from the same source developed prion infection. All four of the deer injected with B cells and three of four deer receiving platelets from CWD(+) donor deer became PrP(CWD) positive in as little as 6 months postinoculation, whereas none of the four deer receiving blood CD14(+) monocytes developed evidence of CWD infection (immunohistochemistry and Western blot analysis) after 19 months of observation. Results of the Tg(CerPrP) mouse bioassays mirrored those of the native cervid host. These results indicate that CWD blood infectivity is cell associated and suggest a significant role for B cells and platelets in trafficking CWD infectivity in vivo and support earlier tissue-based studies associating putative follicular B cells with PrP(CWD). Localization of CWD infectivity with leukocyte subpopulations may aid in enhancing the sensitivity of blood-based diagnostic assays for CWD and other TSEs.