Macroscopic Characterization of Hepatocellular Carcinoma: An Underexploited Source of Prognostic Factors.

The macroscopic appearance of a tumor such as hepatocellular carcinoma (HCC) may be defined as its phenotype which is de facto dictated by its genotype. Therefore, macroscopic characteristics of HCC are unlikely random but rather reflect genomic traits of cancer, presumably acting as a valuable source of information that can be retrieved and exploited to infer prognosis. This review aims to provide a comprehensive overview of the available data on the prognostic value of macroscopic characterization in HCC. A total of 57 studies meeting eligible criteria were identified, including patients undergoing liver resection (LR; 47 studies, 83%) or liver transplant (LT; 9 studies, 16%). The following macroscopic variables were investigated: tumor size (n = 42 studies), number of nodules (n = 28), vascular invasion (n = 24), bile duct invasion (n = 6), growth pattern (n = 15), resection margin (n = 11), tumor location (n = 6), capsule (n = 2) and satellite (n = 1). Although the selected studies provided insightful data with notable prognostic performances, a lack of standardization and substantial gaps were noted in the report and the analysis of gross findings. This topic remains incompletely covered. While the available studies underscored the value of macroscopic variables in HCC prognostication, important lacks were also observed. Macroscopic characterization of HCC is likely an underexploited source of prognostic factors that must be actively explored by future multidisciplinary research.

Canadian Multicentric Pan-TRK (CANTRK) Immunohistochemistry Harmonization Study.

Tumor-agnostic testing for NTRK1-3 gene rearrangements is required to identify patients who may benefit from TRK inhibitor therapies. The overarching objective of this study was to establish a high-quality pan-TRK immunohistochemistry (IHC) screening assay among 18 large regional pathology laboratories across Canada using pan-TRK monoclonal antibody clone EPR17341 in a ring study design. TRK-fusion positive and negative tumor samples were collected from participating sites, with fusion status confirmed by panel next-generation sequencing assays. Each laboratory received: (1) unstained sections from 30 cases of TRK-fusion-positive or -negative tumors, (2) 2 types of reference standards: TRK calibrator slides and IHC critical assay performance controls (iCAPCs), (3) EPR17341 antibody, and (4) suggestions for developing IHC protocols. Participants were asked to optimize the IHC protocol for their instruments and detection systems by using iCAPCs, to stain the 30 study cases, and to report the percentage scores for membranous, cytoplasmic, and nuclear staining. TRK calibrators were used to assess the analytical sensitivity of IHC protocols developed by using the 2 reference standards. Fifteen of 18 laboratories achieved diagnostic sensitivity of 100% against next-generation sequencing. The diagnostic specificity ranged from 40% to 90%. The results did not differ significantly between positive scores based on the presence of any type of staining vs the presence of overall staining in ≥1% of cells. The median limit of detection measured by TRK calibrators was 76,000 molecules/cell (range 38,000 to >200,000 molecules/cell). Three different patterns of staining were observed in 19 TRK-positive cases, cytoplasmic-only in 7 samples, nuclear and cytoplasmic in 9 samples, and cytoplasmic and membranous in 3 samples. The Canadian multicentric pan-TRK study illustrates a successful strategy to accelerate the multicenter harmonization and implementation of pan-TRK immunohistochemical screening that achieves high diagnostic sensitivity by using laboratory-developed tests where laboratories used centrally developed reference materials. The measurement of analytical sensitivity by using TRK calibrators provided additional insights into IHC protocol performance.

Programmed death-ligand1 is a determinant of recurrence in alveolar echinococcosis.

OBJECTIVES: Alveolar echinococcosis (AE) recurrence is one of the major stakes in patients undergoing surgery, the main curative treatment. Preliminary data demonstrated an effect of programmed death-ligand1 (PD-L1) inhibitors on AE proliferation in animals. The current study aimed to analyze the prognostic value of PD-L1 expression in tissue samples of patients with AE undergoing surgery. METHODS: A cross-sectional study of patients operated for AE between 2002 and 2017 was performed. Patients with recurrence were matched 1: 2 with patients without recurrence. The matching criteria were PNM staging (P = hepatic localization of the parasite, N = extra-hepatic involvement of neighboring organs, and M = absence or presence of metastasis), resection status, preoperative albendazole treatment, and lesion size. PD-L1 immunohistochemistry staining was performed in surgical liver specimens. The expression of PD-L1 was assessed in immune cells. Disease-free survival was calculated using the Kaplan-Meier method. RESULTS: Among 68 consecutive patients, eight patients with recurrence were matched to 16 patients without recurrence. PD-L1 was overexpressed in patients with recurrence (recurrence: PD-L1 <1%: one, PD-L1 ≥1%: seven; no recurrence: PD-L1 <1%: nine, PD-L1 ≥1%: seven, P = 0.040). Moreover, patients with lower PD-L1 expression (<1%) showed better median disease-free survival (120 months, 95% confidence interval 104-135 vs 74, 95% confidence interval 44-104, P = 0.050). CONCLUSION: These findings highlight the proof of concept of PD-L1 in AE, but further data on its prognostic importance and the role of immune checkpoint blockade as a promising therapeutical strategy are needed.

CANTRK: A Canadian Ring Study to Optimize Detection of NTRK Gene Fusions by Next-Generation RNA Sequencing.

The Canadian NTRK (CANTRK) study is an interlaboratory comparison ring study to optimize testing for neurotrophic receptor tyrosine kinase (NTRK) fusions in Canadian laboratories. Sixteen diagnostic laboratories used next-generation sequencing (NGS) for NTRK1, NTRK2, or NTRK3 fusions. Each laboratory received 12 formalin-fixed, paraffin-embedded tumor samples with unique NTRK fusions and two control non-NTRK fusion samples (one ALK and one ROS1). Laboratories used validated protocols for NGS fusion detection. Panels included Oncomine Comprehensive Assay v3, Oncomine Focus Assay, Oncomine Precision Assay, AmpliSeq for Illumina Focus, TruSight RNA Pan-Cancer Panel, FusionPlex Lung, and QIAseq Multimodal Lung. One sample was withdrawn from analysis because of sample quality issues. Of the remaining 13 samples, 6 of 11 NTRK fusions and both control fusions were detected by all laboratories. Two fusions, WNK2::NTRK2 and STRN3::NTRK2, were not detected by 10 laboratories using the Oncomine Comprehensive or Focus panels, due to absence of WNK2 and STRN3 in panel designs. Two fusions, TPM3::NTRK1 and LMNA::NTRK1, were challenging to detect on the AmpliSeq for Illumina Focus panel because of bioinformatics issues. One ETV6::NTRK3 fusion at low levels was not detected by two laboratories using the TruSight Pan-Cancer Panel. Panels detecting all fusions included FusionPlex Lung, Oncomine Precision, and QIAseq Multimodal Lung. The CANTRK study showed competency in detection of NTRK fusions by NGS across different panels in 16 Canadian laboratories and identified key test issues as targets for improvements.

Single-Cell Analysis Reveals Transcriptomic Features of Drug-Tolerant Persisters and Stromal Adaptation in a Patient-Derived EGFR-Mutated Lung Adenocarcinoma Xenograft Model.

INTRODUCTION: Targeted therapies require life-long treatment, as drug discontinuation invariably leads to tumor recurrence. Recurrence is mainly driven by minor subpopulations of drug-tolerant persister (DTP) cells that survive the cytotoxic drug effect. In lung cancer, DTP studies have mainly been conducted with cell line models. METHODS: We conducted an in vivo DTP study using a lung adenocarcinoma patient-derived xenograft tumor driven by an EGFR mutation. Daily treatment of tumor-bearing mice for 5 to 6 weeks with the EGFR inhibitor erlotinib markedly shrunk tumors and generated DTPs, which were analyzed by whole exome, bulk population transcriptome, and single-cell RNA sequencing. RESULTS: The DTP tumors maintained the genomic clonal architecture of untreated baseline (BL) tumors but had reduced proliferation. Single-cell RNA sequencing identified a rare (approximately 4%) subpopulation of BL cells (DTP-like) with transcriptomic similarity to DTP cells and intermediate activity of pathways that are up-regulated in DTPs. Furthermore, the predominant transforming growth factor-ß activated cancer-associated fibroblast (CAF) population in BL tumors was replaced by a CAF population enriched for IL6 production. In vitro experiments indicate that these populations interconvert depending on the levels of transforming growth factor-ß versus NF-κB signaling, which is modulated by tyrosine kinase inhibitor presence. The DTPs had signs of increased NF-κB and STAT3 signaling, which may promote their survival. CONCLUSIONS: The DTPs may arise from a specific preexisting subpopulation of cancer cells with partial activation of specific drug resistance pathways. Tyrosine kinase inhibitor treatment induces DTPs revealing greater activation of these pathways while converting the major preexisting CAF population into a new state that may further promote DTP survival.

Retrospective Analysis of Prognostic Factors in Pediatric Patients with Adrenocortical Tumor from Unique Tertiary Center with Long-Term Follow-Up.

Pediatric adrenocortical tumors (PACTs) represent rare causes of malignancies. However, the south/southeast regions of Brazil are known to have a high incidence of PACTs because of the founder effect associated with a germline pathogenic variant of tumor suppressor gene TP53. We aimed to retrospectively analyze the types of variables among hormone production, radiological imaging, tumor staging, histological and genetic features that were associated with the occurrence of malignancy in 95 patients (71% females) with PACTs from a unique center. The worst prognosis was associated with those aged > 3 years (p < 0.05), high serum levels of 11-desoxicortisol (p < 0.001), tumor weight ≥ 200 g (p < 0.001), tumor size ≥ 5 cm (p < 0.05), Weiss score ≥ 5 (p < 0.05), Wieneke index ≥ 3 (p < 0.001) and Ki67 ≥ 15% (p < 0.05). Furthermore, patients with MacFarlane stage IV had an overall survival rate almost two times shorter than patients with other stages (p < 0.001). Additionally, the subtractions of BUB1B-PINK1 (<6.95) expression (p < 0.05) and IGF-IR overexpression (p = 0.0001) were associated with malignant behavior. These results helped identify patients who are likely to have an aggressive course; further multicenter prospective studies are required to confirm our results. In conclusion, PACTs with these patterns of prognostic factors could be treated using an adjuvant approach that may improve the overall survival in such patients.

Integrative analysis of non-small cell lung cancer patient-derived xenografts identifies distinct proteotypes associated with patient outcomes.

Non-small cell lung cancer (NSCLC) is the leading cause of cancer deaths worldwide. Only a fraction of NSCLC harbor actionable driver mutations and there is an urgent need for patient-derived model systems that will enable the development of new targeted therapies. NSCLC and other cancers display profound proteome remodeling compared to normal tissue that is not predicted by DNA or RNA analyses. Here, we generate 137 NSCLC patient-derived xenografts (PDXs) that recapitulate the histology and molecular features of primary NSCLC. Proteome analysis of the PDX models reveals 3 adenocarcinoma and 2 squamous cell carcinoma proteotypes that are associated with different patient outcomes, protein-phosphotyrosine profiles, signatures of activated pathways and candidate targets, and in adenocarcinoma, stromal immune features. These findings portend proteome-based NSCLC classification and treatment and support the PDX resource as a viable model for the development of new targeted therapies.

Non-Alcoholic Fatty Liver Disease-Related Hepatocellular Carcinoma: Immunohistochemical Assessment of Markers of Cancer Cell Metabolism.

INTRODUCTION: Hepatocellular carcinoma (HCC) has been associated to non-alcoholic fatty liver disease (NAFLD). We sought to investigate the immunoexpression of several glycolytic metabolism-associated markers in patients with HCC associated to NAFLD and associate these factors to their clinical-pathological characteristics. METHODS: We evaluated 35 HCC specimens from 21 patients diagnosed with non-alcoholic steatohepatitis (NASH) undergoing liver resection (12 patients), liver transplantation (8 patients), or both (1 patient). Histological features, clinical aspects, demographic and biochemical data, as well as the immunohistochemical reactivity for monocarboxylate transporters 1, 2, and 4; their chaperone CD147; carbonic anhydrase IX; and glucose transporter-1 (GLUT1) were assessed. RESULTS: Metabolic-associated cirrhosis was present in 12 of the 21 patients (8 child A and 4 child B scores). From 9 patients without cirrhosis, 3 presented NASH F3 and 6 NASH F2. Sixteen (76%) had diabetes mellitus, 17 (81%) arterial hypertension, and 19 (90%) body mass index above 25 kg/m2; 8 (38%) had dyslipidemia. From 35 nodules, steatosis was found in 26, ballooning in 31 nodules, 25 of them diagnosed as steatohepatitic subtype of HCC. MCT4 immunoexpression was associated with extensive intratumoral fibrosis, advanced clinical stages, and shorter overall survival. GLUT1 was noticeable in nodules with extensive intratumoral steatosis, higher intratumoral fibrosis, and advanced clinical stages. Immunohistochemical expression of the metabolic biomarkers MCT4 and GLUT1 was higher in patients with Barcelona-clinic liver cancer B or C. GLUT1 correlated with higher degree of steatosis, marked ballooning, intratumoral fibrosis, and higher parenchymal necroinflammatory activity. CONCLUSION: Our data indicate that the expression of the glycolytic phenotype of metabolic markers, especially GLUT1 and MCT4, correlates with a more severe course of HCC occurring in NASH patients.

Antitumor efficacy of XPO1 inhibitor Selinexor in KRAS-mutant lung adenocarcinoma patient-derived xenografts.

Gain-of-function Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations occur in 25% of lung adenocarcinomas, and these tumors are challenging to treat. Some preclinical work, largely based on cell lines, suggested KRASmut lung cancers are especially dependent on the nuclear export protein exportin-1 (XPO1), while other work supports XPO1 being a broader cancer dependency. To investigate the sensitivity of KRASmut lung cancers to XPO1 inhibition in models that more closely match clinical tumors, we treated 10 independently established lung cancer patient-derived tumor xenografts (PDXs) with the clinical XPO1 inhibitor, Selinexor. Monotherapy with Selinexor reduced tumor growth in all KRASmut PDXs, which included 4 different codon mutations, and was more effective than the clinical MEK1/2 inhibitor, Trametinib. Selinexor was equally effective in KRASG12C and KRASG12D tumors, with TP53 mutations being a biomarker for a weaker drug response. By mining genome-wide dropout datasets, we identified XPO1 as a universal cancer cell dependency and confirmed this functionally in two KRASWT PDX models harboring kinase drivers. However, targeted kinase inhibitors were more effective than Selinexor in these models. Our findings support continued investigation of XPO1 inhibitors in KRASmut lung adenocarcinoma, regardless of the codon alteration.

Experimental Models of Liquid Biopsy in Hepatocellular Carcinoma Reveal Clone-Dependent Release of Circulating Tumor DNA.

Liquid biopsy, the molecular analysis of tumor components released into the bloodstream, has emerged as a noninvasive and resourceful means to access genomic information from cancers. Most data derived from translational studies showcase its numerous potential clinical applications. However, data from experimental models are scarce, and little is known about the underlying mechanisms and factors controlling the release of circulating tumor DNA (ctDNA) and cells (CTCs). This study aimed to model liquid biopsy in hepatocellular carcinoma xenografts and to study the dynamics of release of ctDNA and CTCs; this included models of intratumoral heterogeneity (ITH) and metastatic disease. We quantified ctDNA by quantitative polymerase chain reaction (PCR) targeting human long interspersed nuclear element group 1; targeted mutation analysis was performed with digital droplet PCR. CTCs were traced by flow cytometry. Results demonstrated the feasibility of detecting ctDNA, including clone-specific mutations, as well as CTCs in blood samples of mice. In addition, the concentration of ctDNA and presence of tumor-specific mutations reflected tumor progression, and detection of CTCs was associated with metastases. Our ITH model suggested differences in the release of DNA fragments impacted by the cell-clone origin and the treatment. Conclusion: These data present new models to study liquid biopsy and its underlying mechanisms and highlighted a clone-dependent release of ctDNA into the bloodstream.

Transcriptomic characterization of cancer-testis antigens identifies MAGEA3 as a driver of tumor progression in hepatocellular carcinoma.

Cancer testis antigens (CTAs) are an extensive gene family with a unique expression pattern restricted to germ cells, but aberrantly reactivated in cancer tissues. Studies indicate that the expression (or re-expression) of CTAs within the MAGE-A family is common in hepatocellular carcinoma (HCC). However, no systematic characterization has yet been reported. The aim of this study is to perform a comprehensive profile of CTA de-regulation in HCC and experimentally evaluate the role of MAGEA3 as a driver of HCC progression. The transcriptomic analysis of 44 multi-regionally sampled HCCs from 12 patients identified high intra-tumor heterogeneity of CTAs. In addition, a subset of CTAs was significantly overexpressed in histologically poorly differentiated regions. Further analysis of CTAs in larger patient cohorts revealed high CTA expression related to worse overall survival and several other markers of poor prognosis. Functional analysis of MAGEA3 was performed in human HCC cell lines by gene silencing and in a genetic mouse model by overexpression of MAGEA3 in the liver. Knockdown of MAGEA3 decreased cell proliferation, colony formation and increased apoptosis. MAGEA3 overexpression was associated with more aggressive tumors in vivo. In conclusion MAGEA3 enhances tumor progression and should be considered as a novel therapeutic target in HCC.

Patient-derived tumor xenograft and organoid models established from resected pancreatic, duodenal and biliary cancers.

Patient-derived xenograft (PDX) and their xenograft-derived organoid (XDO) models that recapitulate the genotypic and phenotypic landscape of patient cancers could help to advance research and lead to improved clinical management. PDX models were established from 276 pancreato-duodenal and biliary cancer resections. Initial, passage 0 (P0) engraftment rates were 59% (118/199) for pancreatic, 86% (25/29) for duodenal, and 35% (17/48) for biliary ductal tumors. Pancreatic ductal adenocarcinoma (PDAC), had a P0 engraftment rate of 62% (105/169). KRAS mutant and wild-type PDAC models were molecularly profiled, and XDO models were generated to perform initial drug response evaluations. Subsets of PDAC PDX models showed global copy number variants and gene expression profiles that were retained with serial passaging, and they showed a spectrum of somatic mutations represented in patient tumors. PDAC XDO models were established, with a success rate of 71% (10/14). Pathway activation of KRAS-MAPK in PDXs was independent of KRAS mutational status. Four wild-type KRAS models were characterized by one with EGFR (L747-P753 del), two with BRAF alterations (N486_P490del or V600E), and one with triple negative KRAS/EGFR/BRAF. Model OCIP256, characterized by BRAF (N486-P490 del), had activated phospho-ERK. A combination treatment of a pan-RAF inhibitor (LY3009120) and a MEK inhibitor (trametinib) effectively suppressed phospho-ERK and inhibited growth of OCIP256 XDO and PDX models. PDAC/duodenal adenocarcinoma have high success rates forming PDX/organoid and retaining their phenotypic and genotypic features. These models may be effective tools to evaluate novel drug combination therapies.

Clinical Impact of Pathological Features Including the Ki-67 Labeling Index on Diagnosis and Prognosis of Adult and Pediatric Adrenocortical Tumors.

Adrenocortical tumors (ACT) in the adult and pediatric population are generally considered distinct entities due to differences in molecular events related to tumorigenesis, clinical presentation, and outcome. Furthermore, pathological criteria used for diagnosis and prognostication of ACT in adults are usually inadequate for predicting the biological behavior of ACT in children. Here, we analyzed 146 adult and 44 pediatric (< 15y/o) ACT with long-term clinical follow-up and furthered current evidence on the clinical and pathological differences between pediatric and adult tumors. Predilection for female over male gender was observed in both cohorts, but more so in adults (84% vs. 61%, p = 0.003). Cushing syndrome was more frequent in adults (p < 0.001), whereas virilization, either isolated (p < 0.001) or combined to Cushing (p = 0.047), was more common in children. The Ki67 labelling index (LI) of pediatric adenomas and carcinomas was much higher than their corresponding tumors in adults (p < 0.001). Despite these differences, pathological analyses including the evaluation of Ki67 greatly improved patient prognostication in both age cohorts. Indeed, increased Weiss scores and Ki67 indexes correlated with poor overall- and disease-free survival in adult patients with carcinoma. Among the proliferative indexes tested, Ki67 LI ≥ 10% showed the highest hazard ratio (HR) for recurrence and the Ki67 LI ≥ 3% showed the highest HR for survival. In pediatric tumors, the Wieneke score (p < 0.001) and the Ki67 LI (p < 0.001) showed high accuracy for predicting biological behavior, and increased scores/indexes correlated with worse overall and disease-free survival. In this age cohort, Ki67 LI < 10% was able to rule out malignant behavior, whereas Ki67 LI ≥ 15% may be used to predict the patients with higher risks of recurrence and/or poor outcome.

Hepatic mesenchymal hamartoma and undifferentiated embryonal sarcoma of the liver: a pathologic review.

This review highlights two rare entities that are predominantly seen in children: hepatic mesenchymal hamartoma (HMH) and undifferentiated embryonal sarcoma of the liver (UESL). HMH is a benign lesion predominantly seen in the first 2 years of life, while UESL is malignant and usually identified in patients between 6 and 10 years of age. UESL may arise in the background of HMH, and the association has been supported by similar chromosomal aberrations (19q13.4). The diagnosis of both lesions is primarily based on histologic evaluation, as the clinical and radiological features are not always typical. The clinicopathologic characteristics, pathogenesis, differential diagnoses and treatment for both lesions are discussed.

EGFR-mutated lung adenocarcinomas from patients who progressed on EGFR-inhibitors show high engraftment rates in xenograft models.

OBJECTIVE: Patient-derived xenografts (PDX) are useful preclinical models to study cancer biology and mechanisms of drug response/resistance, particularly in molecularly targetable tumors. However, PDX engraftment may not be stochastic. We investigated clinical, histological and molecular features associated with PDX engraftment in a large cohort of EGFR-mutated lung adenocarcinoma (LUAD). MATERIAL AND METHODS: Samples were collected by different methods from patients at various disease stages and phases of treatment. PDX engraftment was defined as an ability to passage tumors twice in NOD-SCID mice. Uni- and multivariate logistic regression evaluated factors associated with engraftment. RESULTS: Among 138 EGFR-mutated LUAD implanted into NOD-SCID mice, the overall engraftment rate was only 10% (14/138). However, engraftment was significantly higher in specimens from surgical resections or core-needle biopsies collected from metastatic sites (5/5; 100%) or from patients who had progressed on EGFR-inhibitors (7/10; 70%). Engrafted tumors usually showed poor histological differentiation, a solid morphologic pattern, and presence of either EGFR T790 M and/or TP53 mutations. CONCLUSIONS: Population level analyses of mutant EGFR-PDX show that these models might not fully recapitulate the inter-patient heterogeneity of EGFR-LUAD. However, mutant EGFR-PDXs may be useful to address key clinical questions, notably development of resistance to EGFR-inhibitors and disease progression to distant metastases.

Intratumoral heterogeneity and clonal evolution in liver cancer.

Clonal evolution of a tumor ecosystem depends on different selection pressures that are principally immune and treatment mediated. We integrate RNA-seq, DNA sequencing, TCR-seq and SNP array data across multiple regions of liver cancer specimens to map spatio-temporal interactions between cancer and immune cells. We investigate how these interactions reflect intra-tumor heterogeneity (ITH) by correlating regional neo-epitope and viral antigen burden with the regional adaptive immune response. Regional expression of passenger mutations dominantly recruits adaptive responses as opposed to hepatitis B virus and cancer-testis antigens. We detect different clonal expansion of the adaptive immune system in distant regions of the same tumor. An ITH-based gene signature improves single-biopsy patient survival predictions and an expression survey of 38,553 single cells across 7 regions of 2 patients further reveals heterogeneity in liver cancer. These data quantify transcriptomic ITH and how the different components of the HCC ecosystem interact during cancer evolution.

Organoid Cultures as Preclinical Models of Non-Small Cell Lung Cancer.

PURPOSE: Non-small cell lung cancer (NSCLC) is the most common cause of cancer-related deaths worldwide. There is an unmet need to develop novel clinically relevant models of NSCLC to accelerate identification of drug targets and our understanding of the disease. EXPERIMENTAL DESIGN: Thirty surgically resected NSCLC primary patient tissue and 35 previously established patient-derived xenograft (PDX) models were processed for organoid culture establishment. Organoids were histologically and molecularly characterized by cytology and histology, exome sequencing, and RNA-sequencing analysis. Tumorigenicity was assessed through subcutaneous injection of organoids in NOD/SCID mice. Organoids were subjected to drug testing using EGFR, FGFR, and MEK-targeted therapies. RESULTS: We have identified cell culture conditions favoring the establishment of short-term and long-term expansion of NSCLC organoids derived from primary lung patient and PDX tumor tissue. The NSCLC organoids recapitulated the histology of the patient and PDX tumor. They also retained tumorigenicity, as evidenced by cytologic features of malignancy, xenograft formation, preservation of mutations, copy number aberrations, and gene expression profiles between the organoid and matched parental tumor tissue by whole-exome and RNA sequencing. NSCLC organoid models also preserved the sensitivity of the matched parental tumor to targeted therapeutics, and could be used to validate or discover biomarker-drug combinations. CONCLUSIONS: Our panel of NSCLC organoids closely recapitulates the genomics and biology of patient tumors, and is a potential platform for drug testing and biomarker validation.

Hepatocellular carcinoma in non-alcoholic fatty liver disease (NAFLD) - pathological evidence for a predominance of steatohepatitic inflammatory non-proliferative subtype.

OBJECTIVES: This study evaluated clinical and pathological aspects of patients with hepatocellular carcinoma (HCC) secondary to non-alcoholic fatty liver disease (NAFLD) and related these factors to immunohistochemical markers representative of the proliferative class. METHODS: We evaluated 35 HCC nodules from 21 patients diagnosed with NAFLD undergoing liver resection (n=12) or liver transplantation (n=8) or both (n=1). Demographic, clinical and biochemical data were compared to histological features and to immunohistochemical reactivity for K19 and Ki-67. RESULTS: Cirrhosis was present in 58% of patients. Ages ranged from 50 to 77 years. Sixteen patients (76%) were male and had type 2 diabetes mellitus, 81% had arterial hypertension, and 90% had BMI above 25 kg/m². Alpha-fetoprotein levels were normal in 62% of patients. Twenty-five (70%) nodules were diagnosed as "steatohepatitic HCC". Only 32% of the nodules presented high levels of Ki-67 (>10%) and/or K19 (>5%), although 63% were poorly differentiated (G.3/G.4) according to Edmondson & Steiner grading system. K19 positivity (>5%) was associated with higher degree of intratumoral inflammation (G.2/G.3), and with fibrosis, both at the center of the tumor and at the tumor front, whereas Ki-67 positivity (>10%) was associated with ballooning of neoplastic cells and occurred in more than 70% in non-cirrhotic patients. CONCLUSION: NAFLD-related HCC was found in non-cirrhotic patients in 42% of cases, alpha-fetoprotein level was normal in 63% and "steatohepatitic HCC" was the predominant histological type. Immunoexpression of K19 and/or Ki-67 occurred in 32% of the nodules and were associated with intratumoral inflammation and ballooning, suggesting that HCC in MtS may be preferentially "an inflammatory, non-proliferative subtype of HCC".