Informing Wildlife Corridor Creation through Population Genetics of an Arboreal Marsupial in a Fragmented Landscape.

Habitat loss and fragmentation contribute significantly to the decline of arboreal mammal populations. As populations become fragmented and isolated, a reduction in gene flow can result in a loss of genetic diversity and have an overall impact upon long-term persistence. Creating wildlife corridors can mitigate such effects by increasing the movement and dispersal of animals, thus acting to reduce population isolation. To evaluate the success of a corridor, a before-after experimental research framework can be used. Here, we report the genetic diversity and structure of sugar glider (Petaurus breviceps) sampling locations within a fragmented landscape prior to the implementation of a wildlife corridor. This study used 5999 genome-wide SNPs from 94 sugar gliders caught from 8 locations in a fragmented landscape in south-eastern New South Wales, Australia. Overall genetic structure was limited, and gene flow was detected across the landscape. Our findings indicate that the study area contains one large population. A major highway dissecting the landscape did not act as a significant barrier to dispersal, though this may be because of its relatively new presence in the landscape (completed in 2018). Future studies may yet indicate its long-term impact as a barrier to gene flow. Future work should aim to repeat the methods of this study to examine the medium-to-long-term impacts of the wildlife corridor on sugar gliders, as well as examine the genetic structure of other native, specialist species in the landscape.

Conservation genomics of an endangered arboreal mammal following the 2019-2020 Australian megafire.

The impacts of a changing climate threaten species, populations and ecosystems. Despite these significant and large-scale impacts on threatened species, many remain understudied and have little to no genetic information available. The greater glider, Petauroides volans, is an endangered species highly sensitive to the predicted changes in temperature under a changing climate and was recently severely impacted by a megafire natural disaster (85% estimated population loss). Baseline genetic data is essential for conservation management and for detecting detrimental changes in fire-effected populations. We collected genetic samples within 2 years post the 2019-2020 catastrophic Australian bushfires to examine adaptive potential, baseline genetic diversity and population structure, across their southern range in the state of New South Wales. Population genomic analyses were conducted using 8493 genome-wide SNPs for 86 greater glider individuals across 14 geographic locations. Substantial genetic structure was detected across locations, with low genetic diversity and effective population sizes observed in isolated areas. Additionally, we found signals of putative adaptation in response to temperature in greater gliders using a genotype-environment association analysis. These findings have important implications for the management of greater glider populations by identifying at-risk populations and identifying adaptive potential. We demonstrate the importance of baseline genetic information for endangered species as a practical approach to conservation. This is particularly important given the threat that changes in temperatures and megafire events, as predicted under a changing climate, poses for this species.

Semiquantitative classification (SQC) and Oxford classifications predict poor renal outcome better than The International Study of Kidney Disease in Children (ISKDC) and Haas in patients with IgAV nephritis: a multicenter study.

INTRODUCTION: Several histologic classifications are used in the evaluation of IgA vasculitis nephritis (IgAVN), however, to date, no studies have determined which one has the strongest association with the severity of IgAVN and, as a consequence, its outcomes. MATERIALS AND METHODS: Patients included in the study were diagnosed with IgAV and IgAVN in seven tertiary university medical centers in Croatia, Italy and Israel. The International Study of Kidney Disease in Children (ISKDC), Haas, Oxford, and Semiquantitative classification (SQC) classifications were used in the analysis and description of renal biopsy. Time from biopsy to outcome evaluation was a statistically significant factor in outcome prediction that was used to define the base model, and was a covariate in all the tested models. RESULTS: Sixty-seven patients were included in this study. The SQC classification proved to be the best one in outcome prediction, followed by the Oxford classification. The ISKDC and Haas classifications could not predict renal outcome. The Oxford parameters for mesangial hypercellularity and tubular atrophy, as well as the SQC parameters for cellular crescents showed an independent statistically significant contribution to outcome prediction. High level of twenty-four hour protein excretion was associated with a higher grade in the Oxford, SQC and ISKDC classifications. Endocapillary proliferation was positively associated with the Pediatric Vasculitis Activity Score (PVAS) at diagnosis, while tubular atrophy was negatively associated. CONCLUSION: The SQC, followed by the Oxford classification were found to provide the best classifications of renal biopsy analysis in patients to predict the outcome in patients with IgAVN. Cellular crescents, mesangial hypercellularity and tubular atrophy showed significant contributions, indicating that active and chronic variables should be included in the estimation.

Estimating the density of small mammals using the selfie trap is an effective camera trapping method.

Camera trapping to study wildlife allows for data collection, without the need to capture animals. Traditionally, camera traps have been used to target larger terrestrial mammal species, though recently novel methods and adjustments in procedures have meant camera traps can be used to study small mammals. The selfie trap (a camera trapping method) may present robust sampling and ecological study of small mammals. This study aimed to evaluate the selfie trap method in terms of its ability to detect species and estimate population density. To address this aim, standard small mammal live trapping was undertaken, immediately followed by camera trapping using the selfie trap. Both methods were set to target the arboreal sugar glider (Petaurus breviceps) and semi-arboreal brown antechinus (Antechinus stuartii). The more ground-dwelling bush rat (Rattus fuscipes) was also live trapped and recorded on camera. Across four survey areas, the probability of detection for each of the three species was higher for selfie traps than for live trapping. Spatially explicit capture-recapture models showed that selfie traps were superior at estimating density for brown antechinus and sugar gliders, when compared to simulated live trapping data. Hit rates (number of videos per various time intervals) were correlated with abundance. When correlating various hit rate intervals with abundance, the use of 10-min hit rate was best for predicting sugar glider abundance (R2 = 0.94). The abundance of brown antechinus was estimated from selfie traps using a 24-h hit rate as a predictor (R2 = 0.85). For sugar gliders, the selfie trap can replace live trapping as individuals can be identified through their unique facial stripes and natural ear scars, and thus used in capture-recapture analysis. This method may be useful for monitoring the abundance of other small mammal species that can also be individually recognized from photographs. Supplementary Information: The online version contains supplementary material available at 10.1007/s13364-022-00643-5.

Clinical efficacy and safety of adalimumab versus etanercept in patients with ankylosing spondylitis and total spinal ankylosis in Croatia: a multicentre 12-month follow-up study.

OBJECTIVE: To evaluate the 12-month efficacy and safety profile of adalimumab and etanercept in patients with ankylosing spondylitis (AS) and total spinal ankylosis (TSA). TYPE OF STUDY DESIGN: Case-series follow-up study. DESIGN: Twenty-eight patients (26 men and 2 women) with active AS (BASDAI > 4) and TSA were treated as follows: 19 patients receiving adalimumab and 9 patients receiving etanercept. Twelve-month data related to the efficacy and safety of these two TNF-alpha inhibitors were evaluated. The primary endpoint was ASAS 20 (the ASsessment in AS International Working Group criteria for 20% improvement) at weeks 12 and 52. Other measures that were evaluated were function (BASFI), disease activity (BASDAI), patient's and physician's global disease assessment on visual analogue scale (VAS) and C-reactive protein. RESULTS: In both adalimumab and etanercept groups, there was a significant improvement in all observed variables (baseline compared to weeks 12 and 52). This improvement was sustained for the whole follow-up period. In the adalimumab group, at week 12, ASAS 20 was achieved in 18/19 patients and at week 52 in 17/19 patients. In the etanercept group, at week 12 ASAS 20 was achieved in all patients and at week 52 in 6/9 patients. CONCLUSION: In patients with active AS and TSA, adalimumab and etanercept treatment showed significant improvement in function and disease activity. No serious side effects or adverse effects were observed in our cohort. Key Points • TNF-alpha inhibitors can be effective treatment options for patients with AS and having total spinal ankylosis. • Patients with advanced AS should not be disregarded as good candidates for treatment with biologic disease-modifying antirheumatic drugs.

The Use of Selfie Camera Traps to Estimate Home Range and Movement Patterns of Small Mammals in a Fragmented Landscape.

The use of camera traps to track individual mammals to estimate home range and movement patterns, has not been previously applied to small mammal species. Our aim was to evaluate the use of camera trapping, using the selfie trap method, to record movements of small mammals within and between fragments of habitat. In a fragmented landscape, 164 cameras were set up across four survey areas, with cameras left to record continuously for 28 nights. Live trapping was performed prior to ear mark animals to facilitate individual identification on camera. Four small mammal species (sugar glider; Petaurus breviceps; brown antechinus; Antechinus stuartii, bush rat; Rattus fuscipes, and brown rat; Rattus norvigecus) were recorded on camera (N = 284 individuals). The maximum distance travelled by an individual sugar glider was 14.66 km, antechinus 4.24 km; bush rat 1.90 km and brown rat 1.28 km. Movements of both female and male sugar gliders in linear fragments were recorded at much higher rates than in larger patches of forest sampled in grids. Short term core homes ranges (50% KDE) of 34 sugar gliders ranged from 0.3 ha to 4.2 ha. Sugar glider core home ranges were on average 1.2 ha (±0.17) for females and 2.4 ha (±0.28) for males. The selfie trap is an efficient camera trapping method for estimating home ranges and movements due to its ability to obtain high recapture rates for multiple species and individuals. In our study landscape, linear strips of habitat were readily utilised by all small mammals, highlighting their importance as wildlife corridors in a fragmented landscape.

USE OF NON-STEROIDAL ANTI-INFLAMMATORY DRUGS IN PATIENTS WITH ADVANCED ACTIVE RHEUMATOID ARTHRITIS.

This study aimed to determine whether patients with active rheumatoid arthritis (RA) regularly take non-steroidal anti-inflammatory drugs (NSAIDs) and to clarify whether their decision to take NSAIDs depends on disease activity, intensity of pain, or functional status. The study also aimed to identify the risk factors for gastrointestinal side effects. Over 6 months, we conducted a cross-sectional single-center study of consecutively hospitalized patients with confirmed RA. Activities of daily living, pain intensity, and disease activity were evaluated by the Health Assessment Questionnaire, visual analog scale, and disease activity score, respectively, in 28 joints. Of 73 patients diagnosed with RA, 48 (66%) regularly took NSAIDs. Compared to non-users, NSAID users used glucocorticoids less frequently. The decision to use NSAIDs was independent of disease activity, pain intensity, degree of functional impairment, or presence of gastrointestinal risk factors. However, a higher degree of functional impairment was associated with a longer duration of continuous NSAID and glucocorticoid use. NSAIDs are still relevant for RA treatment. The decision to use them is not necessarily affected by disease activity or pain intensity, but their prolonged use is required in patients with a higher degree of functional disability. NSAIDs enable exclusion of glucocorticoid use, sparing patients of glucocorticoid-related side effects.

Gastrointestinal involvement and its association with the risk for nephritis in IgA vasculitis.

BACKGROUND: We analysed clinical and biochemical parameters in predicting severe gastrointestinal (GI) manifestations in childhood IgA vasculitis (IgAV) and the risk of developing renal complications. METHODS: A national multicentric retrospective study included children with IgAV reviewed in five Croatian University Centres for paediatric rheumatology in the period 2009-2019. RESULTS: Out of 611 children, 281 (45.99%) had at least one GI manifestation, while 42 of 281 (14.95%) had the most severe GI manifestations. Using logistic regression several clinical risk factors for the severe GI manifestations were identified: generalized rash [odds ratio (OR) 2.09 (95% confidence interval (CI) 1.09-4.01)], rash extended on upper extremities (OR 2.77 (95% CI 1.43-5.34)] or face [OR 3.69 (95% CI 1.42-9.43)] and nephritis (IgAVN) [OR 4.35 (95% CI 2.23-8.50)], as well as lower values of prothrombin time (OR 0.05 (95% CI 0.01-0.62)], fibrinogen [OR 0.45 (95% CI 0.29-0.70)] and IgM [OR 0.10 (95% I 0.03-0.35)]] among the laboratory parameters. Patients with severe GI involvement more frequently had relapse of the disease [OR 2.14 (CI 1.04-4.39)] and recurrent rash [OR 2.61 (CI 1.27-5.38)]. Multivariate logistic regression found that the combination of age, GI symptoms at the beginning of IgAV and severity of GI symptoms were statistically significant predictors of IgAVN. Patients in whom IgAV has started with GI symptoms [OR 6.60 (95% CI 1.67-26.06)], older children [OR 1.22 (95% CI 1.02-1.46)] with severe GI form of IgAV (OR 5.90 (95% CI 1.12-31.15)] were particularly high-risk for developing IgAVN. CONCLUSION: We detected a group of older children with the onset of GI symptoms before other IgAV symptoms and severe GI form of the IgAV, with significantly higher risk for acute and chronic complications of IgAV.

Establishment of Pancreatic Organoids from Normal Tissue and Tumors.

Establishment of patient-derived adult stem cell-based pancreatic (tumor) organoids was first described in 2015. Since then, multiple laboratories have demonstrated the robustness of this method. We recently described the generation of a pancreatic cancer biobank containing 30 well-characterized tumor organoid models. Here, we describe the applied methods in detail. Use of tumor-selective media prevents contamination with normal cells. Generated organoids can be cryopreserved and can serve as a living biobank of pancreatic cancer for biomarker identification and drug screening. For complete information on the generation and use of this protocol, please refer to Driehuis et al. (2019).

Influence of Biological Therapeutics on Patient-Reported Quality-Of-Life Outcomes (Whoqol-Bref), Functional Scores and Disease Activity among Croatian Patients with Rheumatoid Arthritis: Our Experience.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic and disabling disease with a great impact on the quality of life (QOL). The aim of this study was to assess QOL and health in RA patients treated with biological disease-modifying drugs (bDMARDs) as opposed to those treated with conventional synthetic DMARDs (csDMARDs). We analysed four domains of QOL: physical health (D1), mental health (D2), social relationships (D3) and one's surroundings (D4); as well as general quality of life (W1), general state of health (W2), and disease activity and physical disability. SUBJECTS AND METHODS: Seventy-seven RA patients (group A=29 on bDMARDs, group B=48 on csDMARDs) were enrolled in the study. QOL was evaluated using WHO questionnaire (WHOQOL-BREF), disease activity using Disease Activity Score 28C-reactive protein (DAS28CRP) and functional status using Health Assessment Questionnaire (HAQ). RESULTS: There was no statistically significant difference of mean values in the four domains of QOL, nor in the general QOL, between groups A and B. There was also no statistically significant difference regarding RA activity (3.51 vrs 3.54, p=0.56). However, we have found that the variable of the general state of health domain was statistically significantly higher in group B (2.66 vrs 2.89, p=0.001), while HAQ was statistically significantly higher in group A (1.19 vrs 1.07, p=0.018), as well as the duration of RA (6.25vrs 3.75 years, p=0.0006). Statistically significant correlation was found between HAQ and W2, disease duration and D3 in group A and DAS28CRP and D1, D2, W2 and HAQ and D1 and D2 in group B. CONCLUSION: These findings suggest that the inclusion of bDMARDs in the treatment regimen was overdue, with RA already advancing with developed functional disability, which prevented the achievement of the primary goals of treatment: low disease activity or remission and the improvement of patient's QOL.

The effect of smoking on disease activity in rheumatoid arthritis - our experience.

The aim of this study was to investigate the association of smoking with disease activity, seropositivity, age and gender in patients with rheumatoid arthritis. We included 89 rheumatoid arthritis patients. All patients fulfilled the 2010 American College of Rheumatology/European League Against Rheumatism rheumatoid arthritis classification criteria. Activity of the disease was measured by Disease Activity Score 28-joint count C-reactive protein (DAS28CRP). The subjects were stratified into smoking and non-smoking groups and cross-sectionally analyzed. There were 24 (27%) smokers and 65 (73%) nonsmokers. The mean age of patients was 57.1±8.8 years. The mean DAS28CRP was 5.81 in the smoking group and 5.57 in the non-smoking group, without statistically significant difference between the two groups (p=0.148). Similarly, smokers did not differ significantly from non-smokers according to age (p=0.443), gender (p=0.274), rheumatoid factor positivity (p=0.231), anti-citrullinated protein antibody positivity (p=0.754) or seropositivity (p=0.163). In this study, we found no association between smoking status and disease activity, seropositivity, age or gender in rheumatoid arthritis patients. Furthermore, disease activity was not related to age, gender or seropositivity. Additional studies on the effects of smoking on rheumatoid arthritis activity are needed.

Pancreatic cancer organoids recapitulate disease and allow personalized drug screening.

We report the derivation of 30 patient-derived organoid lines (PDOs) from tumors arising in the pancreas and distal bile duct. PDOs recapitulate tumor histology and contain genetic alterations typical of pancreatic cancer. In vitro testing of a panel of 76 therapeutic agents revealed sensitivities currently not exploited in the clinic, and underscores the importance of personalized approaches for effective cancer treatment. The PRMT5 inhibitor EZP015556, shown to target MTAP (a gene commonly lost in pancreatic cancer)-negative tumors, was validated as such, but also appeared to constitute an effective therapy for a subset of MTAP-positive tumors. Taken together, the work presented here provides a platform to identify novel therapeutics to target pancreatic tumor cells using PDOs.

Targeting Tumor Markers with Antisense Peptides: An Example of Human Prostate Specific Antigen.

The purpose of this paper was to outline the development of short peptide targeting of the human prostate specific antigen (hPSA), and to evaluate its effectiveness in staining PSA in human prostate cancer tissue. The targeting of the hPSA antigen by means of antisense peptide AVRDKVG was designed according to a three-step method involving: 1. The selection of the molecular target (hPSA epitope), 2. the modeling of an antisense peptide (paratope) based on the epitope sequence, and 3. the spectroscopic evaluation of sense-antisense peptide binding. We then modified standard hPSA immunohistochemical staining practice by using a biotinylated antisense peptide instead of the standard monoclonal antibody and compared the results of both procedures. Immunochemical testing on human tissue showed the applicability of the antisense peptide technology to human molecular targets. This methodology represents a new approach to deriving peptide ligands and potential lead compounds for the development of novel diagnostic substances, biopharmaceuticals and vaccines.

Do We Pay Enough Attention to Neuropathic Pain in Knee Osteoarthritis Patients?

The aim of the study was to determine the prevalence of neuropathic pain in knee osteoarthritis patients using painDETECT questionnaire, and to evaluate correlations between pain intensity, gender, age and types of treatment, and the presence of neuropathic pain. The study included 122 patients. All participants completed a questionnaire on sociodemographic data, duration of symp-toms, types of treatment and preventable risk factors (body mass index and waist circumference). The presence of neuropathic pain was assessed by painDETECT, according to which subjects were classified into three groups (neuropathic pain likely, possible, or unlikely). Neuropathic pain was likely in 18 (14.8%), possible in 30 (24.6%) and unlikely in 74 (60.7%) subjects. A significant positive correlation was found between visual analog scale for pain and painDETECT score. There was no statistically significant difference in gender, age, waist circumference and body mass index among three groups of participants according to painDETECT score. In conclusion, knee osteoarthritis patients with neuropathic pain component were experiencing higher levels of pain, implicating poorer pain control with common analgesics. Recognizing these patients as a distinct subgroup would allow clinicians to improve their treatment by using unconventional analgesics with central activity.

A Living Biobank of Breast Cancer Organoids Captures Disease Heterogeneity.

Breast cancer (BC) comprises multiple distinct subtypes that differ genetically, pathologically, and clinically. Here, we describe a robust protocol for long-term culturing of human mammary epithelial organoids. Using this protocol, >100 primary and metastatic BC organoid lines were generated, broadly recapitulating the diversity of the disease. BC organoid morphologies typically matched the histopathology, hormone receptor status, and HER2 status of the original tumor. DNA copy number variations as well as sequence changes were consistent within tumor-organoid pairs and largely retained even after extended passaging. BC organoids furthermore populated all major gene-expression-based classification groups and allowed in vitro drug screens that were consistent with in vivo xeno-transplantations and patient response. This study describes a representative collection of well-characterized BC organoids available for cancer research and drug development, as well as a strategy to assess in vitro drug response in a personalized fashion.

Molecular Signaling of Progesterone, Growth Hormone, Wnt, and HER in Mammary Glands of Dogs, Rodents, and Humans: New Treatment Target Identification.

Mammary tumors are the most common form of neoplasia in the bitch. Female dogs are protected when they are spayed before the first estrus cycle, but this effect readily disappears and is already absent when dogs are spayed after the second heat. As the ovaries are removed during spaying, ovarian steroids are assumed to play an essential role in tumor development. The sensitivity toward tumor development is already present during early life, which may be caused by early mutations in stem cells during the first estrus cycles. Later on in life, tumors arise that are mostly steroid-receptor positive, although a small subset of tumors overexpressing human epidermal growth factor 2 (HER2) and some lacking estrogen receptor, progesterone receptor (PR), and HER2 (triple negative) are present, as is the situation in humans. Progesterone (P4), acting through PR, is the major steroid involved in outgrowth of mammary tissue. PRs are expressed in two forms, the progesterone receptor A (PRA) and progesterone receptor B (PRB) isoforms derived from splice variants from a single gene. The dog and the whole family of canids have only a functional PRA isoform, whereas the PRB isoform, if expressed at all, is devoid of intrinsic biological activity. In human breast cancer, overexpression of the PRA isoform is related to more aggressive carcinomas making the dog a unique model to study PRA-related mammary cancer. Administration of P4 to adult dogs results in local mammary expression of growth hormone (GH) and wing less-type mouse mammary tumor virus integration site family 4 (Wnt4). Both proteins play a role in activation of mammary stem cells. In this review, we summarize what is known on P4, GH, and Wnt signaling in canine mammary cancer, how the family of HER receptors could interact with this signaling, and what this means for comparative and translational oncological aspects of human breast cancer development.

Scabies in a Patient with Rheumatoid Arthritis Treated with Adalimumab - A Case Report.

Rheumatoid arthritis is a chronic systemic inflammatory disease characterized by synovitis, erosions, and destruction of affected joints. If untreated, it leads to severe disability and premature mortality. Tumor necrosis factor alpha (TNF-α) inhibitors are biological drugs used in treatment of rheumatoid arthritis. Possible side effects include skin allergic reactions, which, if generalized, are the reason for discontinuation of the drug. We report the case of a 46-year-old female patient with rheumatoid arthritis who presented with pruritus and erythematous papular exanthema after administration of the second dose of adalimumab. At first, we suspected a drug hypersensitivity reaction. As the signs and symptoms persisted for 2 months after discontinuation of adalimumab and despite continuous administration of antihistamines and glucocorticoids, further work-up was performed, and scabies was diagnosed. The patient was treated with topical 10% crotamiton. The symptoms were persistent and additional applications of the preparation were needed. After clinical remission of scabies, treatment of active rheumatoid arthritis with adalimumab was restarted without any complications.

High basal Wnt signaling is further induced by PI3K/mTor inhibition but sensitive to cSRC inhibition in mammary carcinoma cell lines with HER2/3 overexpression.

BACKGROUND: Elevated basal, ligand-independent, Wnt signaling in some canine breast cancer cells is not caused by classical mutations in APC, ß-Catenin or GSK3ß but, at least partially, by enhanced LEF1 expression. We examined the expression and function of EGFR/HER-regulated pathways on the ligand-independent Wnt signaling. METHODS: Twelve canine mammary tumor cell lines with previously reported differential basal Wnt activity were used. The expression levels of genes related to EGF-signaling were analyzed by cluster analysis. Cell lines with a combined overexpression of EGF-related genes and enhanced basal Wnt activity were treated with PI3K/mTor or cSRC inhibitors or transfected with a construct expressing wild-type PTEN. Subsequently, effects were measured on Wnt activity, cell proliferation, gene expression and protein level. RESULTS: High basal Wnt/LEF1 activity was associated with overexpression of HER2/3, ID1, ID2, RAC1 and HSP90 together with low to absent cMET and PTEN mRNA expression, suggesting a connection between Wnt- and HER-signaling pathways. Inhibition of the HER-regulated PI3K/mTor pathway using the dual PI3K/mTor inhibitor BEZ235 or the mTor inhibitor Everolimus® resulted in reduced cell proliferation. In the cell line with high basal Wnt activity, however, an unexpected further increased Wnt activity was found that could be greatly reduced after inhibition of the HER-regulated cSRC activity. Inhibition of the PI3K/mTor pathway was associated with enhanced expression of ß-Catenin, Axin2, MUC1, cMET, EGFR and HER2 and a somewhat increased ß-Catenin protein content, whereas cSRC inhibition was associated with slightly enhanced HER3 and SLUG mRNA expression. A high protein expression of HER3 was found only in a cell line with high basal Wnt activity. CONCLUSIONS: High basal Wnt activity in some mammary cancer cell lines is associated with overexpression of HER-receptor related genes and HER3 protein, and the absence of PTEN. Inhibition of the PI3K/mTor pathway further stimulated, however, canonical Wnt signaling, whereas the inhibitory effect with the cSRC inhibitor Src-I1 on the Wnt activity further suggested a connection between Wnt and HER2/3-signaling.

Organoid models of human and mouse ductal pancreatic cancer.

Pancreatic cancer is one of the most lethal malignancies due to its late diagnosis and limited response to treatment. Tractable methods to identify and interrogate pathways involved in pancreatic tumorigenesis are urgently needed. We established organoid models from normal and neoplastic murine and human pancreas tissues. Pancreatic organoids can be rapidly generated from resected tumors and biopsies, survive cryopreservation, and exhibit ductal- and disease-stage-specific characteristics. Orthotopically transplanted neoplastic organoids recapitulate the full spectrum of tumor development by forming early-grade neoplasms that progress to locally invasive and metastatic carcinomas. Due to their ability to be genetically manipulated, organoids are a platform to probe genetic cooperation. Comprehensive transcriptional and proteomic analyses of murine pancreatic organoids revealed genes and pathways altered during disease progression. The confirmation of many of these protein changes in human tissues demonstrates that organoids are a facile model system to discover characteristics of this deadly malignancy.