GalNAc-conjugated siRNA targeting the DNAJB1-PRKACA fusion junction in fibrolamellar hepatocellular carcinoma.

Fibrolamellar hepatocellular carcinoma (FLC) is a rare liver cancer caused by a dominant recurrent fusion of the heat shock protein (DNAJB1) and the catalytic subunit of protein kinase A (PRKACA). Current therapies such as chemotherapy and radiation have limited efficacy, and new treatment options are needed urgently. We have previously shown that FLC tumors are dependent on the fusion kinase DNAJB1::PRKACA, making the oncokinase an ideal drug target. mRNA degrading modalities such as antisense oligonucleotides or small interfering RNAs (siRNAs) provide an opportunity to specifically target the fusion junction. Here, we identify a potent and specific siRNA that inhibits DNAJB1::PRKACA expression. We found expression of the asialoglycoprotein receptor in FLC to be maintained at sufficient levels to effectively deliver siRNA conjugated to the GalNAc ligand. We observe productive uptake and siRNA activity in FLC patient-derived xenografts (PDX) models in vitro and in vivo. Knockdown of DNAJB1::PRKACA results in durable growth inhibition of FLC PDX in vivo with no detectable toxicities. Our results suggest that this approach could be a treatment option for FLC patients.

A qualitative study on healthcare professional and patient perspectives on nurse-led virtual prostate cancer survivorship care.

BACKGROUND: Virtual nurse-led care models designed with health care professionals (HCPs) and patients may support addressing unmet prostate cancer (PCa) survivor needs. Within this context, we aimed to better understand the optimal design of a service model for a proposed nurse-led PCa follow-up care platform (Ned Nurse). METHODS: A qualitative descriptive study exploring follow-up and virtual care experiences to inform a nurse-led virtual clinic (Ned Nurse) with an a priori convenience sample of 10 HCPs and 10 patients. We provide a health ecosystem readiness checklist mapping facilitators onto CFIR and Proctor's implementation outcomes. RESULTS: We show that barriers within the current standard of care include: fragmented follow-up, patient uncertainty, and long, persisting wait times despite telemedicine modalities. Participants indicate that a nurse-led clinic should be scoped to coordinate care and support patient self-management, with digital literacy considerations. CONCLUSION: A nurse-led follow-up care model for PCa is seen by HCPs as acceptable, feasible, and appropriate for care delivery. Patients value its potential to provide role clarity, reinforce continuity of care, enhance mental health support, and increase access to timely and targeted care. These findings inform design, development, and implementation strategies for digital health interventions within complex settings, revealing opportunities to optimally situate these interventions to improve care.

Prostate cancer (PCa) survivors in Canada receive follow-up care after treatment through a specialist-led model, which is currently straining to meet patient needs. We interviewed healthcare providers (HCPs) and patients to investigate the design and development of a healthcare service that uses technology, also known as virtual care, to provide nurse-led follow-up care. Mixed experiences with virtual care informed participant feedback and concerns, including impacts of the pandemic and digital literacy considerations. We show that HCPs and patients see potential benefit in virtual nurse-led follow-up care if it can increase access to resources, clarify patient and provider care roles, and improve access and continuity of care. This type of approach to follow-up care may help to improve survivor quality of life and PCa follow-up care while extending the reach of healthcare systems with limited resources.

An Actionable Expert-System Algorithm to Support Nurse-Led Cancer Survivorship Care: Algorithm Development Study.

BACKGROUND: Comprehensive models of survivorship care are necessary to improve access to and coordination of care. New models of care provide the opportunity to address the complexity of physical and psychosocial problems and long-term health needs experienced by patients following cancer treatment. OBJECTIVE: This paper presents our expert-informed, rules-based survivorship algorithm to build a nurse-led model of survivorship care to support men living with prostate cancer (PCa). The algorithm is called No Evidence of Disease (Ned) and supports timelier decision-making, enhanced safety, and continuity of care. METHODS: An initial rule set was developed and refined through working groups with clinical experts across Canada (eg, nurse experts, physician experts, and scientists; n=20), and patient partners (n=3). Algorithm priorities were defined through a multidisciplinary consensus meeting with clinical nurse specialists, nurse scientists, nurse practitioners, urologic oncologists, urologists, and radiation oncologists (n=17). The system was refined and validated using the nominal group technique. RESULTS: Four levels of alert classification were established, initiated by responses on the Expanded Prostate Cancer Index Composite for Clinical Practice survey, and mediated by changes in minimal clinically important different alert thresholds, alert history, and clinical urgency with patient autonomy influencing clinical acuity. Patient autonomy was supported through tailored education as a first line of response, and alert escalation depending on a patient-initiated request for a nurse consultation. CONCLUSIONS: The Ned algorithm is positioned to facilitate PCa nurse-led care models with a high nurse-to-patient ratio. This novel expert-informed PCa survivorship care algorithm contains a defined escalation pathway for clinically urgent symptoms while honoring patient preference. Though further validation is required through a pragmatic trial, we anticipate the Ned algorithm will support timelier decision-making and enhance continuity of care through the automation of more frequent automated checkpoints, while empowering patients to self-manage their symptoms more effectively than standard care. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1136/bmjopen-2020-045806.

Maturation of metastases in peripheral neuroblastic tumors (neuroblastoma) of children.

Peripheral neuroblastic tumors of childhood exhibit 3 principal neural crest lineages: primitive neuroblastoma, ganglioneuroblastoma, and ganglioneuroma. They are unique in undergoing maturation of neurons (ganglion cells) and Schwann cells, thereby recapitulating normal fetal neuronal development in the brain. Precision in estimating neurogenesis is enhanced by immunoreactivities of markers of neuronal maturation. Whether organ tissue factors in different sites of metastases influence rates of maturation and whether metastases are similar to their primary neuroblastic tumor are incompletely documented. Four young children, 1 with a mixed primary adrenal tumor and 3 with metastases were studied at surgery or autopsy. Immunocytochemical reactivities included microtubule-associated protein-2, synaptophysin, chromogranin-A, somatostatin, keratan sulfate, vimentin, S-100ß protein, and PHOX2B. Primary tumors were non-uniform with regions of either poor or enhanced maturation. Both neuronal and Schwannian lineages were represented in each tumor type but differed in proportions. Bi- or multi-nucleated ganglion cells matured equal to mononuclear forms. Ganglion cell maturation was similar in metastases regardless of the target organ. Metastases resembled primary tumors. Immunocytochemical markers of neuronal and of Schwann cell maturation provide greater diagnostic precision to supplement histological criteria. Interval between diagnosis of primary tumor and metastases, metastatic target tissues, and chemotherapy over an interval of time do not appear to influence neuroblastic or Schwann cell differentiation.

Oncogenic Addiction of Fibrolamellar Hepatocellular Carcinoma to the Fusion Kinase DNAJB1-PRKACA.

PURPOSE: Gene fusions are drivers of many pediatric tumors. In fibrolamellar hepatocellular carcinoma (FLC), a fusion of DNAJB1 and PRKACA is the dominant recurrent mutation. Expression of the DNAJB1-PRKACA fusion gene in mice results in a tumor that recapitulates FLC. However, it is not known whether transient expression of DNAJB1-PRKACA is sufficient only to trigger tumor formation or whether ongoing expression is necessary for maintenance and progression. EXPERIMENTAL DESIGN: We screened short hairpin RNAs (shRNA) tiled over the fusion junction and identified several potent and specific candidates in vitro and two independent FLC patient-derived xenografts (PDX). RESULTS: We show that continued DNAJB1-PRKACA expression is not only required for continued tumor growth, but additionally its inhibition results in cell death. Inhibition of DNAJB1-PRKACA by an inducible shRNA in cells of PDX of FLC resulted in cell death in vitro. Induction of the shRNA inhibits FLC tumors growing in mice with no effect on xenografts from a hepatocellular carcinoma cell line engineered to express DNAJB1-PRKACA. CONCLUSIONS: Our results validate DNAJB1-PRKACA as the oncogene in FLC and demonstrate both a continued requirement for the oncogene for tumor growth as well as an oncogenic addiction that can be exploited for targeted therapies. We anticipate our approach will be useful for investigations of other fusion genes in pediatric cancers and spur development of precision therapies.

Targeting BCL-XL in fibrolamellar hepatocellular carcinoma.

Fibrolamellar hepatocellular carcinoma (FLC) is a rare and often lethal liver cancer with no proven effective systemic therapy. Inhibition of the antiapoptotic protein BCL-XL was found to synergize with a variety of systemic therapies in vitro using cells dissociated from patient-derived xenografts (PDX) of FLC or cells dissociated directly from surgical patient resections. As BCL-XL is physiologically expressed in platelets, prior efforts to leverage this vulnerability in other cancers have been hampered by severe thrombocytopenia. To overcome this toxicity, we treated FLC models with DT2216, a proteolysis targeting chimera (PROTAC) that directs BCL-XL for degradation via the von Hippel-Lindau (VHL) E3 ligase, which is minimally expressed in platelets. The combination of irinotecan and DT2216 in vitro on cells directly acquired from patients or in vivo using several xenografts derived from patients with FLC demonstrated remarkable synergy and at clinically achievable doses not associated with significant thrombocytopenia.

Human liver organoids for disease modeling of fibrolamellar carcinoma.

Fibrolamellar carcinoma (FLC) is a rare, often lethal, liver cancer affecting adolescents and young adults, for which there are no approved therapeutics. The development of therapeutics is hampered by a lack of in vitro models. Organoids have shown utility as a model system for studying many diseases. In this study, tumor tissue and the adjacent non-tumor liver were obtained at the time of surgery. The tissue was dissociated and grown as organoids. We developed 21 patient-derived organoid lines: 12 from metastases, three from the liver tumor and six from adjacent non-tumor liver. These patient-derived FLC organoids recapitulate the histologic morphology, immunohistochemistry, and transcriptome of the patient tumor. Patient-derived FLC organoids were used in a preliminary high-throughput drug screen to show proof of concept for the identification of therapeutics. This model system has the potential to improve our understanding of this rare cancer and holds significant promise for drug testing and development.

Loss of full-length pumilio 1 abrogates miRNA-221-induced gene p27 silencing-mediated cell proliferation in the heart.

Upregulated expression of microRNA (miR)-221 is associated with downregulation of p27 and subsequent increased cell proliferation in a variety of human cancers. It is unknown whether miR-221 mimics could trigger neoplastic cellular proliferation. In vitro, we demonstrated miR-221 significantly downregulates the expression of P27 and increases proliferation of H9c2 and cardiac fibroblasts. The knockdown of PUM1 but not PUM2 abolished such effects by miR-221, as verified by RT-qPCR and western blot, direct binding of p27 3' UTR by luciferase reporter assay and cell proliferation by Ki67. In vivo expression of P27 in the rat liver, heart, kidney, spleen, and muscle were not affected by miR-221 at 1 and 4 mg/kg and concurrently full-length (FL) PUM1 (140 kDa) was not detected. Instead, isoforms of 105 and 90 kDa were observed and generated through alternative RNA slicing verified by cDNA cloning and sequencing and cathepsin K cleavage confirmed by studies with the inhibitor odanacatib. This is the first study to address the possible pro-proliferative effects of miR-221 mimic therapeutics in cardiovascular applications. Loss of FL PUM1 expression is a key factor abrogating miR-221-mediated p27 regulation, although other concurrent mechanisms cannot be excluded. Our findings provide essential insights into the context-dependent nature of miRNA functionality.

Identification of Novel Therapeutic Targets for Fibrolamellar Carcinoma Using Patient-Derived Xenografts and Direct-from-Patient Screening.

To repurpose therapeutics for fibrolamellar carcinoma (FLC), we developed and validated patient-derived xenografts (PDX) from surgical resections. Most agents used clinically and inhibitors of oncogenes overexpressed in FLC showed little efficacy on PDX. A high-throughput functional drug screen found primary and metastatic FLC were vulnerable to clinically available inhibitors of TOPO1 and HDAC and to napabucasin. Napabucasin's efficacy was mediated through reactive oxygen species and inhibition of translation initiation, and specific inhibition of eIF4A was effective. The sensitivity of each PDX line inversely correlated with expression of the antiapoptotic protein Bcl-xL, and inhibition of Bcl-xL synergized with other drugs. Screening directly on cells dissociated from patient resections validated these results. This demonstrates that a direct functional screen on patient tumors provides therapeutically informative data within a clinically useful time frame. Identifying these novel therapeutic targets and combination therapies is an urgent need, as effective therapeutics for FLC are currently unavailable. SIGNIFICANCE: Therapeutics informed by genomics have not yielded effective therapies for FLC. A functional screen identified TOPO1, HDAC inhibitors, and napabucasin as efficacious and synergistic with inhibition of Bcl-xL. Validation on cells dissociated directly from patient tumors demonstrates the ability for functional precision medicine in a solid tumor.This article is highlighted in the In This Issue feature, p. 2355.

ILAE Neuroimaging Task Force highlight: Review MRI scans with semiology in mind.

The ILAE Neuroimaging Task Force aims to publish educational case reports highlighting basic aspects related to neuroimaging in epilepsy consistent with the educational mission of the ILAE. It is important to obtain MRI scans early in the clinical course of epilepsy, using an optimized protocol. Furthermore, it is critical that MRI scans are reviewed by experts who have been provided with all the clinical information and results from other investigations. We report a patient with a 21-year history of drug-resistant seizures who was admitted from another centre for presurgical evaluation. She had four previous MRI scans from this centre which were reported as unremarkable. However, a review of the MRI scan obtained on the day of admission, with the patient's ictal semiology in mind, resulted in identification of an epileptogenic lesion which was later confirmed by video-EEG monitoring and interictal PET. This lesion was present on all previous MRI scans and showed no change. The patient underwent lesionectomy, and histopathology of the resected specimen was consistent with a dysembryoplastic neuroepithelial tumour. The patient remains seizure-free, 2.5 years after surgery. This case highlights the importance of obtaining detailed descriptions of seizure semiology and considering them when reviewing MR images.

Atypical presentation of fulminant primary central nervous system angiitis.

BACKGROUND: Primary Angiitis of the Central Nervous System (PACNS) is a rare cause of CNS vasculitis that should be included as part complete differential diagnosis, especially in cases with suggestive imaging findings and an absence of secondary causes for CNS vasculitis. CASE PRESENTATION: We describe a case of a 47-year-old previously healthy Caucasian male presenting with rapid progression of encephalopathy and fevers. Extensive infectious, autoimmune, and imaging workups were unrevealing. A diagnosis of PACNS was made posthumously on histopathology. CONCLUSIONS: PACNS is a challenging diagnosis owing to frequent discrepancies between radiologic and histopathologic findings. Tissue biopsy is key to diagnosing PACNS.

Early experience with formalin-fixed paraffin-embedded (FFPE) based commercial clinical genomic profiling of gliomas-robust and informative with caveats.

BACKGROUND: Commercial targeted genomic profiling with next generation sequencing using formalin-fixed paraffin embedded (FFPE) tissue has recently entered into clinical use for diagnosis and for the guiding of therapy. However, there is limited independent data regarding the accuracy or robustness of commercial genomic profiling in gliomas. METHODS: As part of patient care, FFPE samples of gliomas from 71 patients were submitted for targeted genomic profiling to one commonly used commercial vendor, Foundation Medicine. Genomic alterations were determined for the following grades or groups of gliomas; Grade I/II, Grade III, primary glioblastomas (GBMs), recurrent primary GBMs, and secondary GBMs. In addition, FFPE samples from the same patients were independently assessed with conventional methods such as immunohistochemistry (IHC), Quantitative real-time PCR (qRT-PCR), or Fluorescence in situ hybridization (FISH) for three genetic alterations: IDH1 mutations, EGFR amplification, and EGFRvIII expression. RESULTS: A total of 100 altered genes were detected by the aforementioned targeted genomic profiling assay. The number of different genomic alterations was significantly different between the five groups of gliomas and consistent with the literature. CDKN2A/B, TP53, and TERT were the most common genomic alterations seen in primary GBMs, whereas IDH1, TP53, and PIK3CA were the most common in secondary GBMs. Targeted genomic profiling demonstrated 92.3%-100% concordance with conventional methods. The targeted genomic profiling report provided an average of 5.5 drugs, and listed an average of 8.4 clinical trials for the 71 glioma patients studied but only a third of the trials were appropriate for glioma patients. CONCLUSIONS: In this limited comparison study, this commercial next generation sequencing based-targeted genomic profiling showed a high concordance rate with conventional methods for the 3 genetic alterations and identified mutations expected for the type of glioma. While it may not be feasible to exhaustively independently validate a commercial genomic profiling assay, examination of a few markers provides some reassurance of its robustness. While potential targeted drugs are recommended based on genetic alterations, to date most targeted therapies have failed in glioblasomas so the usefulness of such recommendations will increase with development of novel and efficacious drugs.

Amyloid-ß-related angiitis: a report of 2 cases with unusual presentations.

Amyloid-ß-related angiitis (ABRA) is a rare complication of cerebral amyloid angiopathy in which amyloid-ß deposition in the leptomeningeal and cortical vessels is associated with vasculitis characterized by transmural lymphohistiocytic, often granulomatous, inflammation. Patients usually present with acute to subacute cognitive dysfunction, headaches, and focal neurologic deficits. We report 2 cases of ABRA with unusual clinical presentations, including one case with fatal cerebral edema leading to herniation and Duret hemorrhages, and another associated with both lobar and deep parenchymal hemorrhages with intraventricular extension as well as hypercoagulability. Both showed extensive vascular amyloid-ß deposition associated with granulomatous angiitis and foreign body-type multinucleated giant cells. One of our cases demonstrates the likely effects of ABRA on impairment of fluid regulation leading to severe cerebral edema, which is an uncommon manifestation of ABRA, and may be a result of impaired blood-brain barrier function or malfunction of the neurovascular unit.

Appendiceal goblet cell carcinoid and mucinous neoplasms are closely associated tumors: lessons from their coexistence in primary tumors and concurrence in peritoneal dissemination.

BACKGROUND: Goblet cell carcinoid (GCC) and appendiceal mucinous neoplasms (AMNs) are considered as different appendiceal tumors. Coexistence of both tumors was occasionally noted. We further observed the concurrence in both primary tumors and their peritoneal dissemination, that is, peritoneal carcinomatosis (PC) including pseudomyxoma peritonei (PMP). METHODS: Review of our 10-year file identified two subgroups of cases with such concurrence. Group 1 is 14 cases of PC/PMP treated by surgical cytoreduction. Morphologic components of GCC, low-grade mucinous neoplasm (LMN), mucinous adenocarcinoma (MCA), and non-mucinous adenocarcinoma (NMCA) were identified separately in different organs/tissues. Group 2 is eight cases of localized primary tumors of appendix and ileocecal junction. RESULTS: In Group 1, primary tumors (11 GCC, 1 GCC + LMN, 1 MCA, 1 NMCA) were identified in appendix (13) and in rectum (1). Further review identified mixed morphologic components in 7/12 GCC cases, including GCC + LMN (2), GCC + MCA (2), GCC + NMCA (1), and GCC + MCA + NMCA (2). Over peritoneal dissemination, GCC and/or other components were coexistent at different sites and in variable combinations. In Group 2, primary tumors were initially diagnosed as GCC (7) and MCA (1). Further review identified mixed components in all cases, including GCC + LMN (3), GCC + LMN + MCA (3), GCC + MCA + NMCA (2). CONCLUSIONS: GCC may present as a component mixed with AMNs and even with conventional adenocarcinoma in both primary tumors and metastatic lesions. AMN in any given single case may show a wide morphologic spectrum. GCC and AMN may share a common tumor stem cell with potential of multiple lineage differentiations.