Successful Establishment Research Articles

Heritability of walnut seed size and the benefits of large seeds

AbstractJapanese walnuts (Juglans mandshurica) are known to be seed‐dispersed by the hoarding of two species of rodents, Japanese squirrels (Sciurus lis) and large Japanese field mice (Apodemus speciosus). The previous study showed that the squirrel transported and stored larger walnut seeds farther, whereas the mice transported smaller seeds farther. Divergent selection by different seed dispersers may play an important role in differentiation between local walnut populations, in which understanding seed size heritability is crucial. This study aims to determine how the seed size selected by rodents affects the initial growth of walnuts and to what extent walnut seed size is genetically determined. Sixty walnut seeds were collected from a small seed‐producing tree, and 50 walnut seeds from a large seed‐producing tree were sown and grown for 18 years. The seed size produced from each tree showed that the heritability of seed size was high (h2 = 0.52). When 50 smaller and 50 larger walnut seeds were planted under the same conditions, the dry weight of shoots and roots of the larger seeds was significantly greater than that of the smaller seeds, and root length was also significantly longer in the larger seeds. Seed size is heritable, so if squirrels are inhabiting, larger seeds, which are advantageous for regeneration, will be selected, and walnut trees producing larger seeds will be passed on to the next generation. Because selective hoarding has implications for seed establishment success, inhabiting a suitable seed disperser, the squirrel, is more critical for walnut regeneration than previously assumed.

Ядерно-физическая медицинская элементология как раздел медицинской радиологии

Purpose: Medical elementology and its subsection nuclear physics medical elementology, as the most important areas of biomedical science, are still insufficiently included in the arsenal of medical radiology as a fundamental basis for the development and use of new methods for diagnosing and treating various diseases, including oncological ones. For the successful establishment of nuclear physics medical elementology as a new scientific discipline, it is necessary to develop a clear methodology for its further development. Results: The definition of the subject of research and the main postulates of medical elementology is given. The close interrelation of knowledge about the content and metabolism of chemical elements, as well as their radioactive and stable isotopes, with the needs of medical radiology is shown. The following areas of research are considered: 1) The use of chemical elements, as well as their radioactive and stable isotopes in medicine; 2) Visualization of organs and tissues, as well as in vivo determination of the content of chemical elements in them; 3) Nuclear physical methods for determining chemical elements in samples of tissues and fluids of the human body in solving oncological problems; 4) The role of chemical elements in calculating absorbed doses during radiotherapy; 5) The use of nuclear physical methods in the formation of groups at increased risk of cancer. A range of modern nuclear physics analytical methods acceptable in clinical practice and as an adequate research tool is outlined. The need for the integrated use of nuclear physics analytical technologies to obtain reference values ​​for the content of chemical elements in various organs, tissues and fluids of the human body in normal and various pathological conditions, as well as to organize the strictest quality control of measurements and unify methodological approaches is demonstrated. The modern possibilities of using the achievements of nuclear physics medical elementology in solving the problems of medical radiology are determined and the priorities for the future are outlined. Conclusion: The steady development of nuclear physical methods of chemical elements analysis and their implementation in medicine is constantly expanding the scope of possibilities of medical elementology. The development of this area will certainly make a significant contribution to the future successes of medical radiology.

Effect of Xuming Decoction in Records of Proved Prescriptions, Ancient a nd Modern on cerebral ischemic injury and angiogenesis in rat model of acute cerebral infarction

This paper aims to explore the effect of Xuming Decoction in the Records of Proved Prescriptions, Ancient and Modern on cerebral ischemic injury and angiogenesis in the rat model of acute cerebral infarction. SD rats were randomized into 6 groups: sham group, model group, low-, medium-, and high-dose(5.13, 10.26, and 20.52 g·kg~(-1), respectively) Xuming Decoction groups, and butylphthalide(0.06 g·kg~(-1)) group. After the successful establishment of the rat model by middle cerebral artery occlusion(MCAO), rats in the sham and model groups were administrated with distilled water and those in other groups with corresponding drugs for 7 consecutive days. After the neurological function was scored, all the rats were sacrificed, and the brain tissue samples were collected. The degree of cerebral ischemic injury was assessed by the neurological deficit score and staining with 2,3,5-triphenyltetrazolium chloride. Hematoxylin-eosin staining was performed to observe the pathological changes in the brain. Transmission electron microscopy was employed to observe the ultrastructures of neurons and microvascular endothelial cells(ECs) on the ischemic side of the brain tissue. Immunofluorescence assay was employed to detect the expression of von Willebrand factor(vWF) and hematopoietic progenitor cell antigen CD34(CD34) in the ischemic brain tissue. Real-time PCR and Western blot were employed to determine the mRNA and protein levels, respectively, of Runt-related transcription factor 1(RUNX1), vascular endothelial growth factor(VEGF), angiopoietin-1(Ang-1), angiopoietin-2(Ang-2), and VEGF receptor 2(VEGFR2) in the ischemic brain tissue. The results showed that compared with the sham group, the model group showed increased neurological deficit score and cerebral infarction area(P<0.01), pathological changes, and damaged ultrastructure of neurons and microvascular ECs in the ischemic brain tissue. Furthermore, the modeling up-regulated the mRNA levels of RUNX1, VEGF, Ang-1, Ang-2, and VEGFR2(P<0.01) and the protein levels of vWF, CD34, RUNX1, VEGF, Ang-1, Ang-2, and VEGFR2(P<0.05 or P<0.01). Compared with the model group, high-dose Xuming Decoction and butylphthalide decreased the neurological deficit score and cerebral infarction area(P<0.01) and alleviated the pathological changes and damage of the ultrastructure of neurons and microvascular ECs in the ischemic brain tissue. Moreover, they up-regulated the mRNA levels of RUNX1, VEGF, Ang-1, Ang-2, and VEGFR2(P<0.01) and the protein levels of vWF, CD34, RUNX1, VEGF, Ang-1, Ang-2, and VEGFR2(P<0.01). The results suggest that Xuming Decoction in the Records of Proved Prescriptions, Ancient and Modern can promote the angiogenesis and collateral circulation establishment to alleviate neurological dysfunction of the ischemic brain tissue in MCAO rats by regulating the RUNX1/VEGF pathway.

Quantifying the roles of climate, herbivory, topography, and vegetation on tree establishment in the treeline ecotone

AbstractThe transition zone between the upper forest boundary and the treeless alpine vegetation (i.e., the treeline ecotone) is expected to shift upward in elevation with global warming. Multiple factors in addition to climate are influencing tree establishment, but it is uncertain to what degree. In this study, we took advantage of a unique dataset with field measurements of mountain birch trees acquired from 32 boreal–alpine treeline ecotone sites situated along a 1100‐km latitudinal gradient in Norway to investigate the role of climate, herbivory, topography, and vegetation on the establishment success of trees. To represent tree establishment, we recorded occurrence, survival, and height growth of short juvenile birch trees (stem height ≤1 m) as response variables at each site in 2008, 2012, and 2018. We used already available climate and herbivory data, and airborne laser scanning (ALS) and unmanned aerial vehicle (UAV) surveyed imagery together with field measurements to compute topography and vegetation explanatory variables per site on microsite scale (approx. 1 m2). We observed a clear decrease in short juvenile birch tree establishment due to livestock herbivory, evidenced by lower occurrence, reduced survival rate, and diminished height growth in treeline ecotones with higher livestock densities. Winter precipitation and the two land cover classes, tree‐covered area and lee side vegetation, were also important for tree establishment. However, the direction and magnitude of the relationships depended on the stage of establishment. While winter precipitation can lead to higher tree occurrence, long‐term survival is not necessarily ensured, reflecting diverse requirements for optimal conditions of tree establishment. Thus, our results show that occurrence, survival, and height growth of short juvenile birch trees differ in their requirements to climate, topography, and vegetation, but tree establishment is consistently low with livestock herbivory. Overall, our results suggest that treeline ecotones will shift toward higher elevations in areas with little or no livestock herbivory and close to already established trees and in lee sides. Regarding management and conservation issues, our results suggest that free‐roaming livestock can reduce tree establishment and hinder treeline ecotone shifts into threatened alpine ecosystems, at least for birch‐dominated treelines.

Effect of chemical or organic fertilizers in mining remnant substrate on forage production and marandu grass morphogenesis

Mining drives economic development, but it frequently alters the fertility of remaining soil or substrates. Increasing organic matter in these substrates has been a critical factor for the successful recovery and establishment of plants. In this study, the development of ‘Marandu’ Urochloa brizantha in a Cambisol substrate, a remnant of bauxite mining, was assessed in the municipality of Poços de Caldas-MG, in response to chemical and organic fertilizers derived from vermicomposting of residues from the production of shimeji mushrooms. An experiment was conducted in a greenhouse, where six treatments, namely: conventional fertilizers (FertConv; FertConv + micro and Cal) and exclusively with the use of vermicompost (20, 40 and 60 t ha-1) were evaluated in a completely randomized design in four replications. Fertilization with vermicompost resulted in significant increases in nutrients. Stem and leaf elongation rates, leaf appearance rate, phyllochron, tiller density and dry matter were influenced by both organic and conventional fertilization. However, the greatest benefits were observed with the application of vermicompost. After 90 days of growth, using conventional fertilization, there were no significant increases in the mentioned variables. The use of vermicompost is effective in improving the fertility conditions of the post-mining substrate, with significant impacts on the development of ‘Marandu’ grass, a fact that can contribute to the recovery of areas impacted by mining. Chemical fertilization based only on chemical fertilizers did not result in increases in TAlC, TAlF, TApF, DPP and DM until 90 days of initial growth of ‘Marandu’ grass.

Expansion of the Distribution Range and Size of the Invasive Blue Crab on the Turkish Coast of the Black Sea

The blue crab (Callinectes sapidus Rathbun, 1896) is an euryhaline species originally native to the western Atlantic Ocean. However, it has expanded its range into the Black Sea, including the Turkish coastal waters. Blue crab specimens were sampled along the Black Sea coast of Türkiye, covering the stretch from Cape Taşkana to the Georgian border. The monitoring studies spanned the period from 2017 to 2024. Analysis of the 16 specimens revealed a carapace width range of 14.8 to 20.3 cm, with males exhibiting larger sizes compared to females. Notably, two of the sampled females were observed to be carrying eggs, highlighting reproductive activity in the region. This study also reports the discovery of the largest blue crab ever recorded on the Turkish coasts of the Black Sea, with a male specimen measuring 20.33 cm in carapace width and weighing 565.1 g. Additionally, a male specimen sampled in the Rize region suggests the species has expanded its range to the easternmost part of the Black Sea. The findings contribute significantly to our understanding of the distribution and growth potential of the blue crab in the Black Sea. The larger sizes observed in males and the presence of ovigerous females indicate successful adaptation and potential establishment of a self-sustaining population. As invasive species, blue crabs can significantly influence benthic communities and food chains, highlighting the importance of a prudent management approach to fisheries biology and ecosystem management

The link between functional response and longevity of Trichogramma evanescens strains indigenous to Türkiye: A comparative assessment of parameters

AbstractA previous comprehensive survey in the Mediterranean and Southeastern regions of Türkiye investigating the natural egg parasitism of lepidopteran maize pests, Sesamia spp, (Lepidoptera: Noctuidae) Ostrinia nubilalis Hbn. and Chilo partellus (Swinhoe; Lepidoptera: Crambidae) by Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae) yielded successful establishment of laboratory cultures of six strains molecularly clustering into two main groups. In this study, the functional response and adult longevity of the strains reared and tested on a factitious host, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) were investigated to provide insights into their potential as candidate biocontrol agents under constant laboratory conditions. The functional response modelling process consisted of two main sequential steps: model selection using polynomial logistic regression and parameter estimation using an iterative maximum likelihood estimation method. The functional response of two strains showed negative linear parameters (type II): HAP068M and HAP268S. Although their attack rate did not differ, the handling time of HAP268S was longer than that of HAP068M. In contrast, four strains had positive linear and negative quadratic parameters (type III) in their functional response: HAP044S, HAP070S, HAP210S, and HAP258M. The strains exhibiting type III functional response did not differ in their handling time, while HAP044S had a higher attack coefficient than HAP070S, HAP210S, and HAP258M. The longevity of both female and male adults significantly differed between strains. More importantly, the females belonging to strains exhibiting type II functional response presented a shorter longevity, compared to those with type III functional response. Males also showed a similar trend in their longevity. This paper discusses the differences in functional response types and estimated parameters of the strains in relation to their relevance for biological control programs and reveals a link between their functional response and longevity as potential reciprocal predictors.

Rapid multiplication of Zingiber cassumunar using axillary bud explant

An in vitro regeneration system was standardized on a traditional medicinal plant of Zingiber cassumunar. The rhizome axillary buds upon transfer to MS basal medium with benzyl adenine (3mg/l) found optimum exhibiting maximum percent of shoot initiation as 92.5 ± 0.6, thereby maximum number of shoots as 6.8 ± 0.3 and maximum number of roots as 22.0 ± 0.4 were found in benzyl adenine (3mg/l) and indole acetic acid (0.5mg/l) combination. The micropropagated plants were transferred to field for successful establishment as 90% respectively. Furthermore, the morphological characteristic analysis was done between the conventional and micropropagated plants which showed very less significant variation. The present protocol reports the propagation of Z. cassumunar plantlets which could be used for commercial exploitation in future.

Litter Mass Loss of the Invasive Rhus typhina L. and Native Koelreuteria paniculata Laxm. Trees Alters Soil N-Fixing Bacterial Community Composition under Different N Forms

Soil N-fixing bacterial (NFB) community may facilitate the successful establishment and invasion of exotic non-nitrogen (N) fixing plants. Invasive plants can negatively affect the NFB community by releasing N during litter decomposition, especially where N input from atmospheric N deposition is high. This study aimed to quantitatively compare the effects of the invasive Rhus typhina L. and native Koelreuteria paniculata Laxm. trees on the litter mass loss, soil physicochemical properties, soil enzyme activities, and the NFB. Following N supplementation at 5 g N m−2 yr−1 in four forms (including ammonium, nitrate, urea, and mixed N with an equal mixture of the three individual N forms), a litterbag-experiment was conducted indoors to simulate the litter decomposition of the two trees. After four months of decomposition, the litter cumulative mass losses of R. typhina under the control, ammonium chloride, potassium nitrate, urea, and mixed N were 57.93%, 57.38%, 58.69%, 63.66%, and 57.57%, respectively. The litter cumulative mass losses of K. paniculata under the control, ammonium chloride, potassium nitrate, urea, and mixed N were 54.98%, 57.99%, 48.14%, 49.02%, and 56.83%, respectively. The litter cumulative mass losses of equally mixed litter from both trees under the control, ammonium chloride, potassium nitrate, urea, and mixed N were 42.95%, 42.29%, 50.42%, 46.18%, and 43.71%, respectively. There were antagonistic responses to the co-decomposition of the two trees. The litter mass loss of the two trees was mainly associated with the taxonomic richness of NFB. The form of N was not significantly associated with the litter mass loss in either species, the mixing effect intensity of the litter co-decomposition of the two species, and NFB alpha diversity. Litter mass loss of R. typhina was significantly higher than that of K. paniculata under urea. The litter mass loss of the two trees under the control and N in four forms mainly affected the relative abundance of numerous NFB taxa, rather than NFB alpha diversity.

Ecological Traits and Socio-Economic Impacts of the Alien Invader Weed Parthenium hysterophorus L. in South Africa’s Rangeland Ecosystems: A Review

Parthenium hysterophorus L. (Asteraceae), commonly known as famine weed in South Africa, is one of the most invasive weeds worldwide, accountable for losses to biodiversity, agriculture, the economy, and the health of livestock and human beings. The spread of this weed is not easy to manage or reverse. With globalization, trade, and human movement, it will continue to spread, allowing its range to expand into new areas. This weed has serious adverse effects on rangeland and agricultural crop production. Because of its unique characteristics, its invasiveness and competitive success rates are attributed to its high reproductive ability, fast growth rate, tolerance to environmental stresses, climate change adaptability, allelopathic potential, and unpalatability to animals. Parthenium hysterophorus dominates diverse habitats by spreading quickly as a contaminant of grain and other crop products and through farm machinery. It is widely distributed and has become problematic in various countries, including South Africa. It has successfully invaded several provinces in the country since its introduction in 1880. Since plant invasions are not universal, this study aimed to review research that has been conducted on the aggressive weed P. hysterophorus to understand the ecological characteristics that enable its successful establishment, the economic costs associated with its detrimental impacts, and to briefly assess knowledge gaps to improve its management strategies.

Transition from Fintech to Techfin

The fundamental goal of any state on the current stage of development is professional and systematic shaping and regulating money stock. Only properly organized cash circulation can foster successful establishment of the finance system and development of economy of the country in general. Today in the field of rendering finance services advanced technologies, digital mechanisms and tools are used, which modernize business-models and raise demand of clients. The future of banking service will be affected mainly by FinTech- and TechFin-companies. The authors studied these economic categories, analyzed key benefits and drawbacks of these structures and forecast their interaction in banking and non -banking fields.

Trained quantity discrimination in invasive red-eared slider and a comparison with the native stripe-necked turtle

Little is known about the behavioral and cognitive traits that best predict invasion success. Evidence is mounting that cognitive performance correlates with survival and fecundity, two pivotal factors for the successful establishment of invasive populations. We assessed the quantity discrimination ability of the globally invasive red-eared slider (Trachemys scripta elegans). We further compared it to that of the native stripe-necked turtle (Mauremys sinensis), which has been previously evaluated for its superior quantity discrimination ability. Specifically, our experimental designs aimed to quantify the learning ability as numerosity pairs increased in difficulty (termed fixed numerosity tests), and the immediate response when turtles were presented with varied challenges concurrently in the same tests (termed mixed numerosity tests). Our findings reaffirm the remarkable ability of freshwater turtles to discern numerical differences as close as 9 vs 10 (ratio = 0.9), which was comparable to the stripe-necked turtle’s performance. However, the red-eared slider exhibited a moderate decrease in performance in high ratio tests, indicating a potentially enhanced cognitive capacity to adapt to novel challenges. Our experimental design is repeatable and is adaptable to a range of freshwater turtles. These findings emphasize the potential importance of cognitive research to the underlying mechanisms of successful species invasions.

Comparative Analysis of the Sedative and Hypnotic Effects among Various Parts of Zizyphus spinosus Hu and Their Chemical Analysis.

Zizyphus spinosus Hu (ZS), as a "medicinal and food-homologous" plant, has been used for a long history. The study was to assess the sedative and hypnotic effects among various parts of ZS. The model, diazepam (DZP), ZS kernel (ZSS), ZS flesh (ZSF), and ZS husk (ZSKS) group occurred subsequent to the successful establishment of the para-chlorophenylalanine induced insomnia model via intraperitoneal injection. The latency and duration of sleep in mice in each group were recorded. The substance basis of various parts of ZS was analyzed by the UPLC-QTOF-MS technique. The results showed that relative to the model group, DZP, ZSS, ZSF, and ZSKS groups demonstrated shortened sleep latency (p < 0.05) and extended sleep duration (p < 0.01). The GABA, 5-HT, and BDNF levels were significantly upregulated in the brain tissues of the mice in the DZP, ZSF, and ZSS groups (p < 0.01). However, the improvement in ZSKS was non-significant. Additionally, the mRNA and protein expression levels of 5-HT1AR, GABAARα1, and BDNF in mice in the DZP, ZSS, and ZSF groups were significantly enhanced (p < 0.01). However, the improvement in the ZSKS group was insignificant (p < 0.05). The examination of the substance composition across different parts revealed that the shared chemical basis contributing to the sedative and hypnotic potency of different parts of ZS may involve the presence of compounds such as (1) magnoflorine, (8) betulinic acid, (9) ceanothic acid, and (10) alphitolic acid. It provides a basis for further elucidation of the substance basis responsible for the functional and medicinal effects of ZS.

Formononetin reverses Treg/Th17 imbalance in immune-mediated bone marrow failure mice by regulating the PI3K/Akt signaling pathway

BackgroundSevere aplastic anemia (SAA) is a syndrome of bone marrow failure which is life-threatening. Recent studies have demonstrated that CD4 + T cell subsets, including T regulatory (Treg) and T helper 17 (Th17) cells, play a pivotal role in the pathogenesis of SAA. Formononetin (FMN) is a natural compound extracted from the traditional Chinese medicine Huangqi, which has the ability to regulate the imbalance of Treg/Th17 cells in some inflammatory diseases. Nevertheless, the therapeutic effect of FMN in SAA has yet to be definitively established. Therefore, the objective of this research was to investigate the effect of FMN on SAA and elucidate its underlying mechanism.MethodsIn vivo experiments, the mice were divided into the following five groups: control, model, low-dose FMN, high-dose FMN, and positive control cyclosporine A group. The immune-mediated bone marrow failure (BMF) mouse model was established by the total body X-ray radiation and lymphocyte infusion. After 10 days of continuous administration of FMN, the numbers of Treg/Th17 cells in the bone marrow and spleen were assessed by flow cytometry. The protein expressions of PI3K/Akt pathway in the bone marrow and spleen was assessed by immunohistochemistry and western blotting. In vitro, the impact of FMN on the differentiation of naive CD4 + T cells into Treg cells was investigated by flow cytometry and ELISA.ResultsIn comparison with the control group, the model group showed a reduction in bone marrow nucleated cells, a significant decrease in peripheral blood cells, and an altered CD8 + /CD4 + T cell ratio. These findings indicate the successful establishment of a mouse model of immune-mediated BMF. After FMN treatment, there were the increased levels of red blood cells and hemoglobin. In addition, FMN mitigated the bone marrow destruction and restored the CD8 + /CD4 + T cell ratio. Furthermore, in comparison with the control group, the model group showed the decreased levels of Treg cells and the increased levels of Th17 cells. After FMN treatment, there was a significantly increased number of Treg cells and a decreased number of Th17 cells. Additionally, FMN remarkably down-regulated the expression levels of PI3K and Akt proteins in immune-mediated BMF mice.ConclusionsFMN alleviates immune-mediated BMF by modulating the balance of Treg/Th17 cells through the PI3K/Akt signaling pathway.

Drivers of tree establishment in planted windbreaks and riparian buffers: A case study of farms in southern Quebec, Canada

Successfully established windbreaks and riparian buffers contribute to protection of soils, crops, watercourses and biodiversity, and help to combat climate change. To improve establishment success of trees planted to form these agroforestry systems, identifying the factors influencing their survival and growth is crucial. We related survival and size of trees planted in windbreaks and riparian buffer strips to 23 abiotic, biotic, structural and technical explanatory factors using multiple generalized linear models. We sampled 52 windbreaks and 26 riparian buffer strips planted in different cultivated fields in southern Quebec (Canada). We analyzed volunteer vegetational composition in the tree planting right-of-way relative to eight explanatory factors. Average survival of planted trees was 86.4% and varied mainly with planting site; tree survival was negatively and significantly correlated with soil pH. We modelled correlations between size of the ten most frequently occurring tree species and 20 explanatory factors, of which six were significant, i.e., method of volunteer vegetation control, soil texture, soil preparation before planting, volunteer vegetation abundance, tree row structure and agroforestry system type (windbreak vs riparian buffer). Relative abundance of different functional types of volunteer vegetation was influenced mainly by the age of agroforestry systems. To increase tree establishment success in winbreaks and riparian buffers, species must be properly selected for planting based upon edaphic conditions, while implementing soil preparation prior to planting and maintaining sufficient spacing between trees to optimize long-term growth. Our results suggest that tree establishment in windbreaks and riparian buffers within an intensive agricultural context should not be perceived as a barrier to their adoption.

Abstract 935: Co-clinical endometrial cancer (EC) patient-derived organoids (PDO) to assess functional effects of replication stress (RS)-targeting agents

Abstract Background: EC is the most commonly diagnosed gynecologic cancer in the US and has both rising incidence and mortality. Uterine serous cancer (USC) and uterine carcinosarcoma (UCS) are high grade ECs characterized by TP53 mutation and molecular alterations suggesting high replication stress (RS) and cell cycle dysregulation. These molecular alterations could engender sensitivity to RS-targeting strategies such as WEE1 inhibition. In a single arm phase 2 of 35 patients, the WEE1 inhibitor adavosertib demonstrated clinical activity in recurrent USC, with an overall response rate of 29.4%. To support the development of predictive biomarkers of sensitivity to RS targeting agents, we report on the establishment of co-clinical EC PDOs from pre- and on-treatment biopsies from patients with USC or UCS enrolled to a translational trial of adavosertib. Methods: Patients with USC or UCS consented for trial participation underwent pre- and on-treatment biopsies while receiving adavosertib monotherapy. Biopsies were dissociated and passaged as 3D organoid cultures in Matrigel in an optimized media. Established PDOs were seeded in 3D microfluidic devices, treated with adavosertib in a dose-dependent manner and assessed for viability after 6 days of treatment by dual labeling live/dead imaging. IC50 values were calculated using log(inhibitor) vs response - variable slope (four parameters) model in GraphPad Prism. To assess the effect of adavosertib on replication fork speed, DNA fiber assays were conducted with PDOs treated with adavosertib for 72 hours. Finally, FFPE blocks were created from PDOs for assessment of DNA damage repair biomarkers by IHC. Results: 19 biopsies were obtained from 11 participating patients. 6 biopsies did not yield sufficient tumor cells for PDO generation. From the remaining 13 samples, 5 PDOs were successfully established (3 USC and 2 UCS), with a higher success rate when 3 biopsy cores were received (3 of 4; 75%) compared to when 2 biopsy cores were received (2 of 9; 22 %). Dual labeling live/dead imaging of PDOs treated with adavosertib resulted in IC50 values ranging from 113nM to 856nM. DNA fiber assays revealed consistent decrease in fork speed with adavosertib exposure, consistent with the hypothesized effect of adavosertib in increasing RS in these cells. A dose dependent effect on replication fork speed was observed, with greater decreases in fork speed with increasing concentrations of adavosertib. Due to the limited number of samples and the number of PDOs generated from on-treatment as opposed to pre-treatment biopsies, clinical correlation between PDO adavosertib sensitivity and clinical activity was not formally assessed. IHC analysis of potential DNA damage biomarkers is ongoing. Conclusions: We describe the successful establishment of co-clinical EC PDOs for functional evaluation of sensitivity to RS targeting agents. Citation Format: Elena Ivanova, Aisha L. Saldanha, Shrabasti Roychoudhury, Bose Kochupurakkal, Ari P. Zlota, Clare E. Padrick, Ha V. Vo, Eli K. Greenberg, Hannah Sawyer, Carina Feeney, Courtney H. Qi, Swati Narayan, Jennifer D. Curtis, Nabihah Tayob, Marisa R. Nucci, Panagiotis Konstantinopoulos, Dipanjan Chowdhury, Geoffrey Shapiro, Cloud P. Paweletz, Ursula A. Matulonis, Joyce F. Liu. Co-clinical endometrial cancer (EC) patient-derived organoids (PDO) to assess functional effects of replication stress (RS)-targeting agents [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 935.

Abstract 2271: Conservation and faithful representation of circular extrachromosomal DNA in orthotopic patient-derived medulloblastoma xenografts

Abstract Background: Extrachromosomal DNA (ecDNA) is a driver of tumor heterogeneity and is associated with poor survival in many different adult and childhood cancer types. Patient-derived xenograft (PDX) models facilitate preclinical drug testing in an in vivo environment that enables analysis of tumor growth and survival and molecular tumor profiling. These models, combined with single-cell profiling, can be used to study intratumoral heterogeneity under therapeutic pressure and the emergence of drug resistance. Here we investigate the abundance and conservation of ecDNA in PDX models with the aim of assessing the faithful representation of ecDNA compared to the tumors from which they are derived. Methods: Whole-genome sequencing (WGS) was applied to 27 medulloblastoma (MB) PDX models and their tumors of origin using Amplicon Architect, a tool used to reconstruct focally amplified regions of DNA to provide insights into the landscape of cancer genomes. The frequency of ecDNA in these models was also compared to that of ecDNA in the MB patient population. Optical genome mapping enabled accurate and reliable ecDNA sequence reconstructions. Multiome single-cell RNA and ATAC-sequencing of a PDX tumor enabled analysis of ecDNA conservation and intratumoral heterogeneity compared to similar data previously obtained from the primary tumor. Results: Comparative analyses revealed that ecDNA is largely conserved in PDX models, emphasizing their relevance as faithful models of the primary tumors. In addition, we find that ecDNA is significantly more frequent in MB PDX models (16 out of 27 analyzed patient-derived tumors) as compared to their frequency in the overall patient population (~18% of all medulloblastoma tumors contain ecDNA), suggesting ecDNA as a driver for successful establishment of MB PDX models. Single-cell analysis revealed that ecDNA is omnipresent in almost all PDX tumor cells, while its presence was limited to only ~9% of tumor cells in the primary tumor. Conclusion: Analysis of ecDNA in medulloblastoma primary tumors and in PDX models revealed that ecDNA is preserved in PDX models. This is an important characteristic that renders patient-derived mouse xenografts as faithful models of their primary tumors. These results emphasize the relevance of PDX models for preclinical in vivo studies aimed at analyzing the role of ecDNA under therapeutic pressure and for analyzing clonal selection along with molecular evolution of ecDNA during the development of therapeutic resistance. Citation Format: Rishaan Kenkre, Owen Chapman, Jens Luebeck, Vineet Bafna, Robert Wechsler-Reya, Jill Mesirov, Lukas Chavez. Conservation and faithful representation of circular extrachromosomal DNA in orthotopic patient-derived medulloblastoma xenografts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2271.

Evidence of mesophication following selective cutting and shelterwood in Virginia’s eastern deciduous forest, USA

The replacement of oaks (Quercus) with mesic tree species in the eastern deciduous forests of North America involves a positive feedback loop being driven by fire suppression and climate change. In this study, we explored the impact of timber harvesting as a potential facilitator of mesophication. Young stands resulting from shelterwoods (on federal lands) and selective cutting (on private lands) were sampled to compare the composition and density of seedlings, saplings, and trees in western Virginia, USA. Oak overstory trees had lower importance values and densities at selective cutting sites compared to shelterwood sites. Among saplings, mesic species had higher importance values and densities than oaks at both selective cutting and shelterwood sites. Evidence of mesophication was found at both selective cutting and shelterwood sites; but a higher level of mesophication appeared to be occurring at the selective cutting sites than at shelterwood sites. At selective cutting sites scarlet oak (Quercus coccinea) was absent from all sampled plots and a dense midstory of subcanopy trees, especially eastern redbud (Cercis canadensis), appeared to be hindering successful oak regeneration. Our results indicate timber harvesting, without regard for the composition of the regeneration layer, may facilitate mesophication in the eastern deciduous forest, with selective cutting resulting in more successful establishment of mesic species compared to shelterwoods. These findings have implications for mesophication on private forest lands, where selective cutting is a very common method of timber harvesting.

Abstract 5174: Organoids to predict treatment response in metastatic colorectal cancer (OPTIC)

Abstract Introduction: The inability to predict treatment response results in unnecessary toxicity, decreased efficacy and survival. There is a clinical need for an effective biomarker to select patients for cancer treatment. A promising biomarker for treatment efficacy is response testing on patient-derived organoids (PDOs). For metastatic colorectal cancer (mCRC), larger prospective studies are needed to evaluate the predictive value of standardized PDO screens. Methods: OPTIC is an ongoing prospective multicenter trial (NL61668.041.17, started 2018) that will evaluate the value of tumor PDOs in therapy response prediction. We establish PDOs for mCRC patients from newly obtained biopsies, prior to the start of treatment. We compare PDO sensitivity (area under drug response curve) with patient response measured by changes in biopsied metastatic lesion size on CT scans. Secondary outcome measures are RECIST response and progression-free survival. We evaluate the feasibility of using PDOs as a biomarker by examining drug screen availability in a clinically relevant timeframe of 4 weeks. From 2020 onwards, we incorporated whole genome sequencing (WGS) on fresh-frozen biopsies to correlate drug response in vitro and in vivo, to genetic tumor characteristics. Additionally, PDO screens with experimental drugs based on genetic alterations identified by WGS could be performed. Trial inclusion will continue until 85 PDOs from clinically evaluable patients for standard of care (SOC) treatment are established, with expected completion in Q1 2024. Results: Currently, 206 patients were included in 5 hospitals and 180 biopsies were taken. PDO establishment success gradually increased from 22% in 2018-2020 to 75% in 2023, yielding an overall success rate of 50% (n=84 PDOs and 13 in culture). Critical factors in optimizing culture success were replacement of several growth factors in the culture medium, reducing time to processing and more frequent handling of biopsies. We have established PDOs for comparing with patient response for the following treatment categories: 5-fluorouracil (n=4), CAPOX/FOLFOX (n=23), irinotecan/FOLFIRI (n=11), FOLFOXIRI (n=12), trifluridine/tipiracil (n=14), panitumumab (n=14), encorafenib-cetuximab (n=2), non-SOC drugs (n=4). We have successfully screened the first 8 PDOs in consistent technical triplicates and biological duplicates (R&amp;lt;0.88, p&amp;lt;0.02). WGS succeeded in 76% (n=75), primarily failing when tumor percentage was &amp;lt;20%. Conclusion: We improved PDO establishment success to 75% which is essential to facilitate the implementation of PDOs in clinical treatment. OPTIC will enhance the clinical application of PDOs by defining thresholds for PDO sensitivity and analyzing the diagnostic power for different treatments. To enable personalized treatment in clinical practice, PDO screening should guide mCRC treatment and result in enhanced chance of response and reduced over- and mistreatment. Citation Format: Lidwien P. Smabers, Emerens Wensink, Carla S. Verissimo, Mayke Doorn, Tao Yang, Timo Voskuilen, Yasmine Abouleila, Maarten A. Huismans, Liselot Valkenburg-van Iersel, Geert A. Cirkel, Elske C. Gootjes, Frank J. Jeurissen, Guus M. Bol, Hilde H. Nienhuis, Manon M. Braat, Bas Penning de Vries, Sjoerd G. Elias, Edwin Cuppen, Robert G. Vries, Onno Kranenburg, Miriam Koopman, Sylvia F. Boj, Jeanine M. Roodhart. Organoids to predict treatment response in metastatic colorectal cancer (OPTIC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5174.

Abstract 4258: An innovative PDX and patient-derived 3D platform for improved translatability of new medical entities

Abstract The preclinical platform landscape in oncology has radically changed in the last 15 years, mainly due to an increased ability to generate patient-derived models. Multiple 3D tumor cell cultures methods, either from established cell lines or from primary cultures, have been developed to assess the activity of therapeutic agents in vitro. These methods are strongly influenced by the experimental conditions, such as cell culture conditions, the presence of 3D supports like Matrigel, and the experimental design of the assay, such as the choice of the dose and the duration of the assay. The ability of these methods to predict drug efficacy in the patient relies not only in the optimization of the experimental settings, but also on the representativeness of the patient population, and on the prevention of model drifts due to clonal selection and/or tumor cell adaptation to culture conditions with passages. In this project, we aimed to develop an innovative 3D cell model platform that addresses all these experimental challenges. To do so, we took advantage of our low passage Tumorgraft platform, a bank of more than 1500 patient-derived xenografts (PDXs) well characterized at molecular and pharmacological level and highly representative of the patient population, to generate the Tumorgraft3D platform. We derived TumorGraft3D models from low passage PDXs, by using proprietary, indication-specific culture conditions. By keeping these models at low passage, we were able to avoid clonal drifts. Moreover, the use of indication specific media allowed the preservation of patient’s and PDX’s tumor histology, molecular traits at genetic, gene expression and proteomic level, and displayed proliferation rates that recapitulate those observed in the parental PDXs. So far, we have successfully developed over 100 models from breast, ovarian, prostate, NSCLC, colorectal and gastric indications, with success rates up to 90%. Ex-vivo testing of standard of care highlighted different response profiles in accordance with the molecular feature of these models. The tumor dissociation process and culture conditions optimized with PDXs were also used for the development of 3D cultures derived from patients’ samples. These data demonstrated that our 3D platform can integrate the complementarity of our PDX and patient-derived 3D platform, which lies in the possibility of evaluating test agent activity in the repeatable and reproducible setting provided by the patient-derived 3D models, as well as in models directly derived from patients with more heterogeneous and indication-specific establishment success rate, and throughput dependent on the amount of primary tumor material. Citation Format: Samaneh Kamali, Stefano Cairo, Fu-Ju Chou, Taylor Light, Mara Gilardi, Brandon Walling, Christine Baer, Hsiu-Wen Tsai, Abhay Andar, Karin Abarca-Heidemann, Maria Mancini. An innovative PDX and patient-derived 3D platform for improved translatability of new medical entities [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4258.