Tissue Samples Research Articles

Clinical and immunophenotype correlating with response to immunotherapy in paediatric patients with primary liver carcinoma. A case series

Paediatric hepatocellular carcinomas (HCC) traditionally arise in the context of a normal structural and functional liver and carry a dismal prognosis. While chemotherapy is the frontline standard, there is emerging interest in the study of immunotherapies for paediatric patients with relapsed/refractory disease. There is limited data to support whether immunotherapies will be of utility in this patient population. Six paediatric patients (median age:16 years, range: 12-17at the time of treatment) with advanced hepatocellular neosplams, either conventional hepatocellular or fibrolamellar carcinoma, were treated with immunotherapy. Patients were consented to institutional genomic profiling and biobanking protocols. Baseline samples and serial tissue samples, when available, were evaluated for somatic mutation rate, actionable gene mutations, and pan-immune bulk RNA expression profiling. Results were correlated with clinical course. Three patients responded to checkpoint inhibition: one achieved a complete, durable response and the other two, prolonged stable disease. Three additional patients progressed. Diagnostic tissue from the complete responder demonstrated a higher relative mutational burden and robust immune infiltrate. Pre-treatment samples from the three responders demonstrated decreased expression of genes associated with T-cell dysfunction. A subset of patients with primary paediatric hepatocellular tumours will respond to immunotherapy. Immunotherapies are currently under prospective study for relapsed/refractory liver tumours in paediatric patients. Results from this report support the prospective collection of serial serum and tissue samples which may further identify genomic and immunophenotypic patterns predictive of response. This work was supported by Philanthropic funds (Pan Mass Challenge, Team Angus and Team Perspective).

Therapeutic potentials of Hibiscus trionum: Antioxidant, anti-lipid peroxidative, hypoglycemic, and hepatoprotective effects in type 1 diabetic rats

Recent advances in diabetes treatment have primarily focused on insulin and hypoglycemic agents; however, there is growing interest in exploring herbal and synthetic alternatives. Numerous studies have highlighted the preventive effectiveness of regular plant consumption in managing chronic conditions, particularly diabetes. Hibiscus, a medicinal plant recognized in various cultures, is known for its diverse health benefits. This study investigated the impact of Hibiscus trionum on glycemic control and assessed its influence on glucose and insulin levels in diabetes-induced rats. The concentrations of antioxidant enzymes, particularly superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), were scrutinized across multiple body tissues (plasma, heart, muscle, liver, and kidney). The malondialdehyde (MDA) concentration, an indicator of lipid peroxidation, was examined in both plasma and tissue samples. Serum total cholesterol (TC), triglyceride (TG), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels were evaluated. Diabetic Group (D) exhibited a significant decrease in body weight, increased fluid and food consumption, elevated blood glucose levels, and increased antioxidant enzyme activity. Moreover, the diabetic group also showed increased levels of MDA, TC, TG, AST, and ALT, along with reduced insulin levels, compared to the control group. A substantial improvement in all parameters impaired by diabetes was observed following the application of Hibiscus trionum (HTT) in the Diabetes+HTT group. The antioxidative stress-reducing, lipid peroxidation-improving, and hepatoprotective potential of Hibiscus trionum in mitigating diabetes-induced oxidative stress is noteworthy. These findings indicate that HTT supplementation has valuable beneficial effects in protecting against the harmful impacts of diabetes.

Opportunities for Interventional Radiology in Paediatric Oncology

Interventional oncology (IO) has emerged as a pivotal field within interventional radiology (IR), gaining prominence in the past three decades. It has transcended its initial role in cancer care, expanding beyond biopsies and vascular access to offer a spectrum of percutaneous and transarterial procedures, transforming into a curative and palliative discipline. However, implementing IO in children presents distinctive challenges. While the technical aspects of IO procedures mirror those in adults, paediatric cases require specialised considerations. Radiologists must possess an in-depth understanding of the paediatric disease, tailor imaging modalities to the case, discern unique risks, and interpret disease markers specific to children. Notably, paediatric tumour biopsies demand significantly larger tissue samples for genetic sequencing, staging, and prognostication. Paediatric IO also confronts procedural disparities. Tumours in children may be larger relative to body size, necessitating precise radioembolisation dose calculations. The proximity of critical structures in small bodies amplifies the risk of collateral damage. When performing percutaneous ablation and endovascular therapies, these challenges must also be faced so that radiologists can navigate these complex clinical and technical considerations to ensure safe and effective interventions, all while prioritising the well-being of their young patients. This review summarises the current role and future opportunities for IO in paediatric cancer.

Advancing Standardization in Fat Graft Survival Studies: Assessing the Superiority of Paraepididymal Fat Graft as a Donor Site.

There is currently no standardization in the field of research on fat grafts in rats, which is one of the most popular topics in plastic surgery. The aim of our study was to demonstrate the effects of selecting paraepididymal fat grafts as the donor area on enhancing the reliability of fat graft studies. In this study, 12 male Sprague-Dawley rats were used to obtain adipose grafts from both inguinal and paraepididymal regions. After measuring the graft weights, they were subjected to histological examination using hematoxylin-eosin staining, as well as immunohistochemical staining with antiperilipin antibody. Purity of the samples, viability of adipose cells, and the presence of lymph nodes within the grafts were analyzed. The purity of adipose cells in graft samples obtained from the paraepididymal region was found to be 98.1% compared with the total sample. In contrast, the purity of adipose cells in graft samples obtained from the inguinal region was 58.37%. Hematoxylin-eosin staining revealed significantly higher adipocyte viability and vascularity in the paraepididymal region compared with the inguinal region (P = 0.0134). Conversely, lymphatic tissue content in samples obtained from the inguinal region was significantly higher compared with paraepididymal adipose tissue samples (P < 0.0001). Immunohistochemical staining with antiperilipin antibody showed a denser and more uniform staining pattern in paraepididymal adipose grafts (P < 0.0001). Using paraepididymal fat, devoid of lymphatic tissue, naturally eliminates 2 critical biases (estrogen and lymphatic tissue), enhancing the standardization and reliability of fat graft survival studies.

Plasma and tissue concentrations of 2 g prophylactic cefazolin prior to lower extremity surgery.

Surgical site infections (SSIs) are among the most clinically relevant complications and the use of prophylactic cefazolin is common practice. However, the knowledge about the pharmacological aspects of prophylactic cefazolin in the lower extremities remains limited. In this prospective cohort, a sub-study of the WIFI-2 randomized controlled trial, adults between 18 and 75 years of age who were scheduled for implant removal below the level of the knee and randomized for cefazolin, was included. A maximum of two venous plasma, target-site plasma, and target-site tissue samples were taken during surgery. The primary outcomes were the cefazolin concentrations in venous plasma, target-site plasma, and target-site tissue. A total of 27 patients [median (interquartile range) age, 42 (29-59) years; 17 (63%) male] with 138 samples were included in the study. A minimum of 6 weeks follow-up was available for all patients. The mean (SD) venous plasma, target-site plasma, and target-site tissue concentrations were 36 (13) µg/mL, 29 (13) µg/mL, and 28 (13) µg/g, respectively, and the cefazolin concentrations between the different locations of surgery did not differ significantly in both target-site plasma and target-site tissue (P = 0.822 and P = 0.840). In conclusion, 2 g of prophylactic cefazolin demonstrates adequacy in maintaining coverage for a duration of at least 80 minutes of surgery below the level of the knee, significantly surpassing the MIC90 required to combat the most prevalent microorganisms. This study represents the first of its kind to assess cefazolin concentrations in the lower extremities by examining both plasma and tissue samples in this magnitude.

Hsa_circ_0004872 mitigates proliferation, metastasis and immune escape of meningioma cells by suppressing PD-L1.

Meningioma is a prevalent intracranial malignancy known for its aggressive growth.Circular RNAs (circRNAs) play a crucial role in the development of various cancers. However, theirinvolvement in meningioma remains understudied. This study aimed to investigate the function andunderlying mechanism of hsa_circ_0004872 in meningioma.The molecular expression of hsa_circ_0004872, PD-L1 and EIF4A3 was identified by RT-qPCRand/or western blot assays. Cell viability, migration, and invasion were assessed throughCCK-8 and Transwell assays, respectively. Cytotoxicity was determined using an LDH assay, and cellapoptosis was monitored by flow cytometry. The RNA and protein interactions were assessed throughRNA-protein immunoprecipitation (RIP) and RNA pull down analyses.Our findings revealed that hsa_circ_0004872 expression was significantly downregulated inboth meningioma tissue samples and cells. Overexpression of hsa_circ_0004872 inhibited theproliferation, metastasis, and immune escape of meningioma cells, as well as enhanced the cytotoxicityof CD8+ T cells by suppressing PD-L1. Furthermore, hsa_circ_0004872 directly interacted withEIF4A3, leading to the degradation of PD-L1 mRNA. Finally, inhibiting EIF4A3 improved theproliferation, metastasis, and immune escape of meningioma cells, as well as the cytotoxicity of CD8+T cells.Our study demonstrated that hsa_circ_0004872 mitigated the proliferation, metastasis,and immune escape of meningioma cells by targeting the EIF4A3/PD-L1 axis. These findingssuggested that hsa_circ_0004872 and EIF4A3 might serve as promising biological markers andtherapeutic targets for meningioma treatment.

Extent of foetal exposure to maternal elexacaftor/tezacaftor/ivacaftor during pregnancy.

Cystic fibrosis (CF) patients are living longer and healthier due to improved treatments, e.g. cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy elexacaftor/tezacaftor/ivacaftor (ETI), with treatment possibly occurring in pregnancy. The risk of ETI to foetuses remain unknown. Thus the effect of maternally administered ETI on foetal genetic and structural development was investigated. Pregnant Sprague Dawley rats were orally treated with ETI (6.7mg·kg-1·day-1 elexacaftor + 3.5mg·kg-1·day-1 tezacaftor + 25 mg·kg-1·day-1 ivacaftor) for 7days from E12 to E19. Tissue samples collected at E19 were analysed using histology and RNA sequencing. Histological changes and differentially expressed genes (DEG) were assessed. No overt structural abnormalities were found in foetal pancreas, liver, lung and small intestine after 7-day ETI exposure. Very few non-functionally associated DEG in foetal liver, lung and small intestine were identified using RNA-seq. 29 DEG were identified in thymus (27 up-regulated and two down-regulated) and most were functionally linked to each other. Gene ontology enrichment analysis revealed that multiple muscle-related terms were significantly enriched. Many more DEG were identified in cortex (44 up-regulated and four down-regulated) and a group of these were involved in central nervous system and brain development. Sub-chronic ETI treatment in late pregnancy does not appear to pose a significant risk to the genetic and structural development of many foetal tissues. However, significant gene changes in foetal thymic myoid cells and cortical neuronal development requires future follow-up studies to assess the risk to these organs.

Tissue expression of miR-449a as risk factor for occult neck metastasis in patients with cT3-T4 N0 laryngeal cancer. A pilot study.

To explore the potential role of miR-449a as biomarker for laryngeal squamous cell carcinoma (LSCC), especially in the decision strategy of neck dissection (ND). Each patient underwent total laryngectomy and bilateral ND (levels II-IV); during surgery, tissue samples of around 1 × 0.5cm were extracted from both healthy tissue adjacent to the tumor and the visibly affected tumor tissue. The extraction of total RNA, encompassing miRNA, was performed using a mirVana PARIS kit. To detect miR449a, cDNA was synthesized from 200ng of RNA using a TaqMan miRNA reverse transcription kit. The study group was formed of 66 patients (62 males, and 4 females) with LSCC, aged between 39 and 77years (mean 60 + 14.56yr). MiR-449a was up-regulated in twenty-eight tumors (42%), while it was down-regulated in 38 samples (58%). In the present study, there was a statistical relevance for miR-449a tissue expression for pN staging (p = 0.017), and PNI (p = 0.005). Eight tumors (12%) cN0 became pN + showing occult cervical lymph node metastases at the final histopathological examination, and all of these patients showed miR-449a downregulation. Super-selective ND (sparing the sub evels IIb and IV) might be the approach to cT3-T4 N0 LSCCs with upregulation of miR-449a; on the other hand, to ensure and effective control of occult neck metastases it would be appropriate to reserve elective ND (including sublevels IIb and IV) for cT3-T4 N0 LSCCs with miR-449a downregulation. Although promising, due to the small size of the cohort, the results of this work can be considered preliminary and need to be confirmed by prospective and larger studies.

Chelator boosted tumor-retention and pharmacokinetic properties: development of 64Cu labeled radiopharmaceuticals targeting neurotensin receptor.

Accumulating evidence suggests that neurotensin (NTS) and neurotensin receptors (NTSRs) play key roles in lung cancer progression by triggering multiple oncogenic signaling pathways. This study aims to develop Cu-labeled neurotensin receptor 1 (NTSR1)-targeting agents with the potential for both imaging and therapeutic applications. A series of neurotensin receptor antagonists (NRAs) with variable propylamine (PA) linker length and different chelators were synthesized, including [64Cu]Cu-CB-TE2A-iPA-NRA ([64Cu]Cu-4a-c, i = 1, 2, 3), [64Cu]Cu-NOTA-2PA-NRA ([64Cu]Cu-4d), [64Cu]Cu-DOTA-2PA-NRA ([64Cu]Cu-4e, also known as [64Cu]Cu-3BP-227), and [64Cu]Cu-DOTA-VS-2PA-NRA ([64Cu]Cu-4f). The series of small animal PET/CT were conducted in H1299 lung cancer model. The expression profile of NTSR1 was also confirmed by IHC using patient tissue samples. For most of the compounds studied, PET/CT showed prominent tumor uptake and high tumor-to-background contrast, but the tumor retention was strongly influenced by the chelators used. For previously reported 4e, [64Cu]Cu-labeled derivative showed initial high tumor uptake accompanied by rapid tumor washout at 24h. The newly developed [64Cu]Cu-4d and [64Cu]Cu-4f demonstrated good tumor uptake and tumor-to-background contrast at early time points, but were less promising in tumor retention. In contrast, our lead compound [64Cu]Cu-4b demonstrated 9.57 ± 1.35, 9.44 ± 2.38 and 9.72 ± 4.89%ID/g tumor uptake at 4, 24, and 48h p.i., respectively. Moderate liver uptake (11.97 ± 3.85, 9.80 ± 3.63, and 7.72 ± 4.68%ID/g at 4, 24, and 48h p.i.) was observed with low uptake in most other organs. The PA linker was found to have a significant effect on drug distribution. Compared to [64Cu]Cu-4b, [64Cu]Cu-4a had a lower background, including a greatly reduced liver uptake, while the tumor uptake was only moderately reduced. Meanwhile, [64Cu]Cu-4c showed increased uptake in both the tumor and the liver. The clinical relevance of NTSR1 was also demonstrated by the elevated tumor expression in patient tissue samples. Through the side-by-side comparison, [64Cu]Cu-4b was identified as the lead agent for further evaluation based on its high and sustained tumor uptake and moderate liver uptake. It can not only be used to efficiently detect NTSR1 expression in lung cancer (for diagnosis, patient screening, and treatment monitoring), but also has the great potential to treat NTSR-positive lesions once chelating to the beta emitter 67Cu.

Multiple instance learning for eosinophil quantification of sinonasal histopathology images: A hierarchical determination on whole slide images.

We proposed a hierarchical framework including an unsupervised candidate image selection and a weakly supervised patch image detection based on multiple instance learning (MIL) to effectively estimate eosinophil quantities in tissue samples from whole slide images. MIL is an innovative approach that can help deal with the variability in cell distribution detection and enable automated eosinophil quantification from sinonasal histopathological images with a high degree of accuracy. The study lays the foundation for further research and development in the field of automated histopathological image analysis, and validation on more extensive and diverse datasets will contribute to real-world application.

Histopathological findings of anterior lens capsule in pediatric cataract.

To investigate the histopathological findings of the anterior lens capsule in pediatric patients who had surgery for cataracts. This study is a prospective interventional study. Anterior capsule tissue samples that were obtained by the anterior capsulotomy method during phacoemulsification surgery were fixed and examined under a transmission electron microscope. Twenty-two eyes of 19 patients who were diagnosed with congenital and juvenile cataracts were included in this study. Five patients had associated systemic diseases, including hydrocephalus, cerebral palsy, prematurity, juvenile myelomonocytic leukemia, and Down's syndrome. Electron microscopic evaluation demonstrated single-layered epithelium under the capsule, degenerated organelles with round-oval and prismatic-oval nuclei, and degenerated mitochondria and heterochromatin-rich nuclei. In the case with cerebral palsy, collagen fibrils of the connective tissue and fibroblast-like cells were observed replacing the epithelium that should be underneath the capsule in both eyes, and there was a disorganized distribution of collagen fibrils and vacuole structures in the cytoplasm of fibroblast-like cells. Similar histopathological findings were found in pediatric cataracts with or without systemic disease except in one cerebral palsy case. The absence of lens epithelium may have been a result of degeneration in this patient, and this can be attributed to the presence of systemic inflammation and gliosis in cerebral palsy. The absence of lens epithelium can play a role in the development of dense subcapsular fibrosis and cataract formation.

Multi-element analysis of metals in human pathological and unchanged thyroid glands - pilot study.

Disturbances in the homeostasis of the elemental composition of thyroid tissue may have serious metabolic and health consequences. It is believed that the accumulation of some metals or the deficiency of others may even cause lethal tumours. Due to the fact that metallomics most often uses human serum to analyse macro and microelements as well as trace elements, it was decided to use material that is more difficult to obtain, but also adds credibility to the research - thyroid tissue samples biopsy. The experiments were conducted on 17 patients diagnosed with: nodular (10) and colloidal goitre (2), chronic thyroiditis (2), follicular adenoma (2) and papillary carcinoma (1). They were recruited by collecting a tumour fragment, control fragment and serum from each of them. The content of Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Zn was examined using ICP-OES (Inductively Coupled Plasma - Optical Emission Spectrometers). Simultaneously, biochemical methods were used to determine the markers of inflammation, glycation and peroxidation: malondialdehyde, pentosidine, reactive free amine content, compounds with thiol groups and galectin 3 in the sera of the examined patients. Three statistically significant correlations were identified: Ca-Mg and Cu-Zn in control tissues (p < 0.05) and Cr-Mn in pathological tissues (p < 0.05). A comparison of individual groups of patients shows that there are some potentail tendencies to increase or decrease in the concentration of certain elements or markers of inflammation and glycation, therefore we discuss potential relationships between a given parameter and a thyroid disorder. The pilot study is an introduction to a deeper analysis aimed at tracing the pathomechanism of the development of thyroid diseases, so that the risk of developing these diseases can be effectively minimized.

Molecular characteristics of fowl adenovirus strains detected in broiler chickens on diets without immunostimulant supplements

Abstract Introduction Outbreaks of fowl adenovirus (FAdV) infection in chicken flocks in Poland threaten birds’ health and lives and are rising in frequency. The risk of these infections in immunocompromised poultry flocks with developed clinical symptoms was analysed through virus detection in broiler chicks and correlation of cases with the birds’ immune strength. Material and Methods Samples were analysed from four broiler farms with chicks from the same hatchery in Silesia, Poland where feeding regimes were different. A normal diet was provided to birds on the control farm; a normal diet and probiotic, prebiotic, vitamin and microelement supplementation was supplied on another farm; a normal diet and antibiotics on the third; and a normal diet and both forms of supplementation were given on the fourth farm. Amplification of the virus DNA in a PCR with hexon gene L1 loop hypervariable region 1–4 primers determined the molecular characteristics of isolates of adenovirus strains obtained from necropsy tissue samples. The amplicon sequences were analysed, the pair-wise distances were determined, the maximum likelihood estimate for the gamma parameter for site rates was produced, Tajima’s D neutrality test was run and the relative synonymous codon usage and transition/transversion bias were calculated. Results Two species and two serotypes of fowl adenovirus – MW353018-FAdV-1/A-L-liver and MW353019-FAdV-5/B-I-intestine – were isolated in three-week-old broiler chicks on the control farm. Conclusion Supplementation of broiler chicken flocks with probiotics, prebiotics, vitamins and microelements may have a significant beneficial effect on immunity and can prevent virus infection. The studies provided new information on the molecular characteristics of adenovirus strains isolated from chicks with a low level of immunity.

Characteristics of lipid metabolism after treatment of colon cancer mice with American ginseng vesicles.

Lipid molecules are present in tumours and play an important role in the anti-inflammatory response as well as in antiviral protection. Changes in the type and location of lipids in the intestine following exposure to environmental stressors play an important role in several disorders, including ulcerative colitis (UC), inflammatory bowel disease (IBD), and colorectal cancer. The aim of this work is to provide a new theoretical basis for tumour initiation and development by accurately measuring the spatial distribution of lipids and metabolites in intestinal tissue. Spatial metabolomics allows the detection of samples with minimal sample volume by label-free imaging of complex samples in their original state. The distribution of lipid molecules in tumours has not been reported, although the distribution of lipid molecules in intestinal tissue has been reported in the literature. The range of lipid profiles in colon cancer mouse tumour tissue was compiled using a spatial metabolomics: lipid extraction method. The changes in lipid distribution in two regions after oral administration of American Ginseng (Panax quinquefolius L.) vesicles were also compared. Tumour tissue samples were extracted with 80% methanol-20% formic acid in water. The resulting spatial metabolic profile allowed the identification of seven lipid classes in mouse tumours. The distribution of fibre tissue cells was 23.2% higher than tumour tissue cells, with the exception of the fatty acid (FA) species.

Spatially Resolved Single-Cell Omics: Methods, Challenges, and Future Perspectives.

Overlaying omics data onto spatial biological dimensions has been a promising technology to provide high-resolution insights into the interactome and cellular heterogeneity relative to the organization of the molecular microenvironment of tissue samples in normal and disease states. Spatial omics can be categorized into three major modalities: (a) next-generation sequencing-based assays, (b) imaging-based spatially resolved transcriptomics RNA approaches including in situ hybridization/in situ sequencing, and (c) imaging-based proteomics. These modalities allow assessment of transcripts and proteins at a cellular level, generating large and computationally challenging datasets. The lack of standardized computational pipelines to analyze and integrate these nonuniform structured data has made it necessary to apply artificial intelligence and machine learning strategies to best visualize and translate their complexity. In this review, we summarize the currently available techniques and computational strategies, highlight their advantages and limitations, and discuss their future prospects in the scientific field.

Lipoprotein glomerulopathy with markedly increased arterial stiffness successfully treated with a combination of fenofibrate and losartan: a case report

BackgroundLipoprotein glomerulopathy (LPG) is a apolipoprotein E (ApoE)-related glomerular disease and has been associated with type III hyperlipidemia. Without appropriate treatment, chronic kidney disease (CKD) caused by LPG progresses, and approximately half of the patients develop end-stage kidney disease within 1–27 years of disease onset. However, few studies have highlighted the clinical course of cardiovascular diseases (CVDs) in patients with LPG. Herein, we report the first case of LPG in which the CVD risk was assessed using arterial stiffness.Case presentationA 32-year-old Japanese man was referred to our hospital due to persistent proteinuria. Kidney biopsy showed markedly dilated capillary lumens containing pale-stained thrombi, which stained positively with Oil Red O. Electron microscopy revealed the presence of thrombi in the capillary lumen with low electron density and vacuoles of various sizes in part of the thrombi. Toluidine blue and Sudan IV stains were used to stain the thin sections of Epon-embedded tissue samples for electron microscopy. Sudan IV-positive droplets were observed in the capillary lumens, vascular walls, and cytoplasm of tubular cells. Increased serum ApoE concentration was observed. Liquid chromatography-tandem mass spectrometry of laser-microdissected glomeruli from paraffin sections revealed an increase in ApoE. Direct deoxyribonucleic acid sequencing of ApoE revealed a heterozygous ApoE Sendai mutation (Arg145Pro). The patient was finally diagnosed with LPG with heterozygosity for ApoE-Sendai mutation (Arg145Pro). Notably, at the time of diagnosis, he had markedly increased arterial stiffness for his age. Arterial stiffness was measured using brachial-ankle pulse wave velocity (baPWV), which was equivalent to that of a 56-year-old man. After three months of treatment with fenofibrate and losartan, a significant reduction in proteinuria was achieved along with an improvement in baPWV. Furthermore, these effects were maintained despite the lack of decrease in serum ApoE levels.ConclusionHerein, we report the case of a patient with LPG with markedly increased arterial stiffness at the time of diagnosis, in whom combination therapy with fenofibrate and losartan successfully improved proteinuria and arterial stiffness. To the best of our knowledge, this is the first case report of LPG in which CVD risk was assessed using arterial stiffness.

Topographic analysis of pancreatic cancer by TMA and digital spatial profiling reveals biological complexity with potential therapeutic implications

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal human malignancies. Tissue microarrays (TMA) are an established method of high throughput biomarker interrogation in tissues but may not capture histological features of cancer with potential biological relevance. Topographic TMAs (T-TMAs) representing pathophysiological hallmarks of cancer were constructed from representative, retrospective PDAC diagnostic material, including 72 individual core tissue samples. The T-TMA was interrogated with tissue hybridization-based experiments to confirm the accuracy of the topographic sampling, expression of pro-tumourigenic and immune mediators of cancer, totalling more than 750 individual biomarker analyses. A custom designed Next Generation Sequencing (NGS) panel and a spatial distribution-specific transcriptomic evaluation were also employed. The morphological choice of the pathophysiological hallmarks of cancer was confirmed by protein-specific expression. Quantitative analysis identified topography-specific patterns of expression in the IDO/TGF-β axis; with a heterogeneous relationship of inflammation and desmoplasia across hallmark areas and a general but variable protein and gene expression of c-MET. NGS results highlighted underlying genetic heterogeneity within samples, which may have a confounding influence on the expression of a particular biomarker. T-TMAs, integrated with quantitative biomarker digital scoring, are useful tools to identify hallmark specific expression of biomarkers in pancreatic cancer.

A device for rapid calorimetric measurements on small biological tissue samples

AbstractA new calorimetric technique is described that allows high-throughput heat production rate measurements on small biological tissue samples. The technique is based on the widely used thermopile chip technology combined with an innovative method for precise transport and positioning of samples of different biological materials at the thermal power detector inside the calorimeter. The new transport and positioning technique is a combination of fluidic and mechanical transport, where the latter is realized by a magneto-motor drive. The transport facility ensures good diffusive oxygen penetration into the sample, which is essential for highly metabolically active materials. The proper functioning of the device is demonstrated by measuring the heat production of metabolically active brown adipose tissue, biopsied tegu lizard muscle, and live Drosophila larvae at different stages and temperatures.

Abstract A007: Circulating tumor DNA and tissue staining analyses reveal heterogeneous ERBB2/HER2 status in urothelial cancer

Abstract Human epidermal growth factor receptor 2 (HER2) is encoded by the ERBB2 gene, and frequently mutated, amplified, and/or overexpressed in urothelial cancer (UC). Promising antibody-drug conjugates have led to new interest in HER2 as a UC clinical target. Patient selection for HER2-targeted therapy typically relies on immunohistochemistry (IHC) and fluorescence in-situ hybridization (FISH) of tumor tissue, however DNA sequencing can identify ERBB2 genomic alterations. Accurate biomarker-driven patient selection will be critical to optimize the clinical benefit of HER2-targeted therapy. Therefore, we evaluated plasma circulating tumor DNA (ctDNA) for ERBB2/HER2 status determination in UC, as compared to IHC and FISH of metachronous tissue. 411 plasma samples from 236 metastatic UC patients were profiled with targeted sequencing across &amp;gt;50 genes frequently altered in UC, including dense coverage flanking the ERBB2 locus. Using an established bioinformatics workflow, we determined the presence of ERBB2 alterations (mutations, amplifications, and/or structural variants) in the 181 patients with evidence of ctDNA in ≥1 sample. Clinical records were reviewed for the availability of archival tumor tissue; in total, 81 formalin-fixed paraffin-embedded tissue specimens were retrieved from 23 patients with ctDNA ERBB2 alterations and 20 ERBB2-wildtype controls. HER2 IHC was performed with a polyclonal rabbit anti-human Her2 antibody (Dako) and scored according to gastric cancer guidelines. HER2 FISH was performed with the PathVysion HER-2 DNA Probe Kit. Protein-altering ERBB2 mutations were identified in 14% of evaluable patients, with two-thirds at known oncogenic hotspots. ERBB2 copy gain was detected in 8% of patients overall, 9% when excluding low tumor fraction samples. IHC results were assessable for 82 tissue samples from 43 patients, and 33 patients had at least one sample with positive HER2 staining (2+/3+). IHC scores varied in 16/23 patients with ≥2 tissue samples, with the variation leading to a change in classification (HER2-negative [0/1+] versus positive [2+/3+]) in half (8/16). In two patients with mixed variant histology, the urothelial component showed IHC 3+ while the scores were 2+ (plasmacytoid) and 0 (squamous) in the variant regions. Frequent focal staining patterns were observed with both IHC and FISH. ERBB2 alterations in ctDNA were correlated with IHC positivity – when considering the most recent tissue sample per patient, 79% of ctDNA ERBB2-altered patient’s tumors were also positive by IHC. Conversely, 55% of ctDNA ERBB2-wildtype cases were positive by IHC. FISH results were available from 24 samples (20 positive, 4 negative), all from patients with ctDNA ERBB2 amplification. 18/20 samples with FISH positivity were HER2 IHC 2+/3+; the remaining two samples were IHC 1+. Our results demonstrate significant spatial and/or temporal heterogeneity in ERBB2/HER2 status, with implications for the rational implementation of biomarker-directed (HER2-targeted) therapy in UC. Citation Format: Gillian Vandekerkhove, Andrew J. Murtha, David C. Müller, Kimia Rostin, Carlos Vasquez-Rios, Jussi Nikkola, Maria Stephenson, Emily Fung, Jaskirat Atwal, Karan Parekh, Cecily Q. Bernales, Gráinne Donnellan, Gang Wang, Tilman Todenhöfer, Piet Ost, Peter C. Black, Kim N. Chi, Bernhard J. Eigl, Alexander W. Wyatt. Circulating tumor DNA and tissue staining analyses reveal heterogeneous ERBB2/HER2 status in urothelial cancer [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr A007.

Abstract A023: Stratification of bladder cancer patients with the use of flow cytometry is increasing the diagnostic potential of molecular classifiers

Abstract Recent research suggests the potential categorization of bladder cancer (BLCa) patients into molecular subtypes to aid in the selection of appropriate treatment strategies, be it conventional, targeted, or a combination thereof. However, the practical implementation of molecular classifiers has faced obstacles due to the intricate nature of gene regulation, tumor heterogeneity, and challenges related to tumor sampling caused by substantial stromal infiltration and tumor multifocality. Hence, there is a pressing need for more straightforward marker-based methodologies to assist in genomic and transcriptomic subtyping efforts. Our study addressed this gap by establishing and validating a panel of antibodies for application in flow cytometry (FCM) to enhance the stratification of BLCa patients. We curated a set of 17 FCM markers capable of delineating four cell clusters (epithelial, immune, endothelial, and stromal) and defining tumor classification (basal and luminal), immune infiltration, and hot-target expression on BLCa tissue samples. This FCM panel was deployed on ex vivo tissue samples treated with chemotherapy and targeted therapy agents. Initially tested on a cohort of 10 BLCa tissue samples, our validation of the FCM panel revealed correlations between marker expression and clinical-pathological features, such as the presence of metastasis and heightened immune and stromal infiltration. Notably, samples exhibiting lower claudin-4 levels displayed increased immune infiltration, while those with metastases at diagnosis showcased elevated basal marker expression. The translational potential of the FCM panel was demonstrated in ex vivo experiments where tissue slices from six patients were subjected to chemotherapy and targeted therapy agents, leading to observable shifts in marker expression post-treatment, particularly pronounced with chemotherapy. Noteworthy effects included reductions in epithelial cells expressing FGFR3 and EGFR following targeted therapy with erdafitinib or lapatinib, alongside alterations in the basal/luminal cell ratio indicated by increased CD44, CD90, and CD239 marker expressions. Our findings underscore the value of FCM in categorizing BLCa patients based on specific marker expression, supplementing conventional histological analyses to enhance cancer diagnosis, guide personalized therapeutic approaches, and monitor treatment efficacy. Citation Format: Martina Radic, Federico La Manna, Martina Minoli, Panagiotis Chouvardas, George N. Thalmann, Roland Seiler-Blarer, Marianna Kruithof-de Julio, Bernhard Kiss. Stratification of bladder cancer patients with the use of flow cytometry is increasing the diagnostic potential of molecular classifiers [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr A023.