Type Locality Research Articles

New data on Turkish Pyraloidea: a new species of Hyperlais Marion, 1959 (Lepidoptera: Pyraloidea: Crambidae: Glaphyriinae) and the first report of the little-known Polyochodes albidiscella (Amsel, 1954)

In this study, Hyperlais cakiri sp. nov. is described and illustrated from the east of Türkiye. The new species is compared with the closely related species H. nemausalis (Duponchel, [1834]) and H. elbursalis (Amsel, 1961). Moreover, Polyochodes albidiscella (Amsel, 1954), previously known only from the type locality in Iran, is recorded as new to the Turkish fauna. Male adult and genital pictures of P. albidiscella as well as those of P. farsella (Amsel, 1951) are presented.

The scientific discovery and subsequent history of the douc monkey Pygathrix nemaeus (Linnaeus, 1771) near Da Nang, Vietnam

Abstract In 1750 Pierre Poivre donated the holotype of the douc monkey Pygathrix nemaeus to R.-A. F. de Réaumur. Its type locality is here restricted from “Cochinchine” to near Da Nang, Vietnam. In 1757, Buffon appropriated the holotype for the King’s collection, wrongly inferring that the species lacks ischial callosities, and conflating it with the sifaka of Madagascar. “D’ouc” is evidently a corruption of Voọc, the Vietnamese word for colobine monkey. In 1819, a French crew shot 100 doucs before breakfast on a mountain near Da Nang. In 2016, the whole mountain population was estimated at 70. By 1831 doucs had learnt to fear gunfire, but locals accepted their proximity, and provided some protection from meat-seeking foreigners. Several doucs were collected for museums in the 19th and 20th century; in 1897 two even lived for a fortnight at the Jardin des Plantes, Paris. The douc was observed and collected near Da Nang during its miraculous survival of the Vietnam War; its evergreen forest habitat surprisingly resilient. This situation is rapidly deteriorating, as forests are reduced to isolated pockets, and hunting prohibitions unenforced. The closely-monitored Mount Son Tra douc population was expanding, but tourist development is illegally eroding the Nature Reserve.

Breast Cancer in Patients with Previous Endometriosis Showed Low Aggressive Subtype

Background and Objectives: The association between endometriosis and breast cancer still remains controversial. The aim of this study was to investigate the different subtypes of breast cancer, immunohistochemical markers, hormone receptors, and ki67 proliferation indexes in patients with and without endometriosis and/or adenomyosis. Materials and Methods: All patients with endometriosis and breast cancer were enrolled. Women with endometriosis and breast cancer (Group BC+EN+) were compared to patients with breast cancer without endometriosis (group BC+EN−) and those with endometriosis without breast cancer (group BC-EN+). General population characteristics and histological and immunohistochemical subtypes of breast cancer were compared between groups. Results: Our study included 41 cases affected by both endometriosis and/or adenomyosis and breast cancer (Group BC+EN+) that were matched (1:2) with 82 patients affected only by breast cancer (group BC+EN−) and 82 patients affected only by endometriosis and/or adenomyosis (group BC-EN+). Group BC+EN+ presented a higher percentage of ER receptor expression (83% vs. 70%, p = 0.02), as well as lower values of Ki 67% (15% vs. 24%, p < 0.0001) and HER2+ (9.8% vs. 28%, p = 0.022). These findings were more evident when comparing patients with premenopausal status, while in postmenopausal patients, this difference was no longer significant. Regarding endometriosis, no statistical differences were observed in type or specific localization of the disease among the groups with and without breast cancer. Conclusions: Patients with endometriosis presented lower aggressive breast cancer rates with higher values of ER% and lower values of Ki 67 and HER2neu+. The type and severity of endometriotic diseases seemed not to influence breast cancer occurrence.

Catalogue of species of the subgenus Afromorgus Scholtz, 1986 (Coleoptera: Trogidae: Omorginae) known from the Oriental and Palaearctic Regions, including a description of one new species from the Deccan Plateau in India

In this paper, we describe and illustrate another species of the family Trogidae, Omorgus (Afromorgus) moreshwar Kalawate & Strümpher, new species from the western part of Maharashtra State in India. In addition, a catalogue of all 22 valid species with their available synonyms of the subgenus Afromorgus Scholtz, 1986 known from the Oriental and Palaearctic Regions is presented. For each species we report type depository, type locality, chresonymy and distribution. Lectotypes are designated for the following species: Trox haagi Harold, 1872 (now Omorgus (A.) haagi), Trox indicus Harold, 1872 (now Omorgus (A.) indicus) and Trox lobicollis Arrow, 1927 (now Omorgus (A.) lobicollis). Omorgus (A.) desertorum (Harold, 1872), valid species, is redescribed and raised from a subspecies of Omorgus (A.) niloticus (Harold, 1872).

Leptanilla voldemort sp. nov., a gracile new species of the hypogaeic ant genus Leptanilla (Hymenoptera, Formicidae) from the Pilbara, with a key to Australian Leptanilla

The genus Leptanilla Emery, 1870 of the family Formicidae, subfamily Leptanillinae, comprises miniscule, pale, blind ants that are rarely collected and poorly understood due to their hypogaeic (i.e. underground) lifestyles. Here we describe a new Leptanilla species from two workers collected via subterranean scraping in the arid Pilbara region of Western Australia. Leptanilla voldemortsp. nov. is the second leptanilline species documented in Australia after the elusive Leptanilla swani Wheeler, 1932. Workers of L. voldemortsp. nov. display a remarkably gracile morphology characterised by elongated legs, antennae, and mandibles, and they are easily differentiated from other Leptanilla species. We also provide new measurements for L. swani from two workers found proximally to the type locality of L. voldemortsp. nov. A key to the worker caste of Leptanilla species of the Australian continent is presented.

Typification of the name <i>Cistus</i> × <i>skanbergii</i> Lojac., a rare rockrose extinct in its type locality

In 1885 Lojacono-Pojero described Cistus skanbergi, also known as the dwarf pink rockrose, from the Island of Lampedusa (Sicily, Italy). Despite becoming extinct in its type locality and being very rare in the Mediterranean Basin, during the last decades the plant corresponding to this name, a natural hybrid between C. parviflorus Lam. and C. monspeliensis L., has been successfully cultivated and introduced worldwide for ornamental purposes. The search carried out in several European herbaria allowed to select as lectotype a specimen collected by Lojacono-Pojero and kept at the herbarium of Kew, to detect other isolectotypes, kept in the herbaria of Geneva and Palermo, and to detect another syntype corresponding to a specimen collected by Gussone and currently kept at the herbarium of Palermo.

A new Bothriembryon from the Nullarbor Plain, Western Australia, with insights on the age of Bothriembryon praecursor from Kangaroo Well, Northern Territory

Fossil Bothriembryon specimens were recovered from the northwestern edges of the Nullarbor Plain, Western Australia, ∼300 km inland from the current southern coastline. This locality is significant because extant species of Bothriembryon from the Nullarbor are confined to within 50 km of the coastline. Principle component analysis (PCA) was used to compare the Nullarbor Bothriembryon species with a morphologically comparable extant species from the Eucla Basin, Bothriembryon barretti, and geographically closest fossil species: Bothriembryon kremnobates and Bothriembryon praecursor. Results showed strong support for a new fossil species herein described as Bothriembryon pilkiensis sp. nov. Specimens were found as internal moulds within pisolitic calcrete overlying the early Miocene Colville Sandstone. The chronology of the pisolitic calcrete is poorly studied; here we discuss the results of palynological and U–Th disequilibrium investigations which attempted to constrain the time of deposition and fossilization, with palynology results suggesting the late Pliocene. The type locality of B. praecursor, Kangaroo Well, Northern Territory, was also re-evaluated in age to the early Miocene, using biocorrelation of two balbarid species to taxa found within Riversleigh World Heritage Area assemblages. http://zoobank.org/urn:lsid:zoobank.org:pub:E33B1587-1023-419D-AFE8-11FD8C443A27 Helen E. Ryan [ helen.ryan@museum.wa.gov.au ], Collection and Research Centre, WA Museum, 49 Kew Street, Welshpool, WA, 6106; Kenny J. Travouillon [ Kenny.travouillon@museum.wa.gov.au ], Collection and Research Centre, WA Museum, 49 Kew Street, Welshpool, WA, 6106; Lynne A. Milne [ L.Milne@curtin.edu.au ], School of Earth and Planetary Sciences, Curtin University, Kent Street, Bentley, WA, 6102; Sarah K. Martin [ sarah.martin@dmirs.wa.gov.au ], Geological Survey of Western Australia, Department of Energy, Mines, Industry Regulation and Safety, 100 Plain Street, East Perth, WA, 6004; Kailah M. Thorn [ Kailah.thorn@museum.wa.gov.au ], Collection and Research Centre, WA Museum, 49 Kew Street, Welshpool, WA, 6106; Corey S. Whisson [ corey.whisson@museum.wa.gov.au ], Collection and Research Centre, WA Museum, 49 Kew Street, Welshpool, WA, 6106.

Rediscovery of rare steno-endemic Impatiens violoides Edgew. ex Hook.f. (Balsaminaceae) from Western Himalaya, after 179 years of type collection

Impatiens violoides Edgew. ex Hook.f. (Balsaminaceae) is a little known steno-endemic spurless balsam species that was known only from a single type collection by Edgeworth in 1844. It is rediscovered after a gap of 179 years from its type locality in Shimla district, Himachal Pradesh, Western Himalaya. Augmented and detailed morphological description based on observations of living material is given along with global distribution; information on habitat and associated species, floral morphology photographs and IUCN red list assessment are also provided for the first time.

Taxonomic re-appraisal of Scolopocryptops quadristriatus (Verhoeff, 1934) and a description of a new species from Japan and Taiwan (Chilopoda, Scolopendromorpha, Scolopocryptopidae)

Centipedes of the genus Scolopocryptops Newport, 1844 are blind species mostly described from the New World and East Asia. In this study, a Japanese species, S. quadristriatus (Verhoeff, 1934), which is characterised by four longitudinal keels on the tergites, is re-described, based on the likely holotype preserved in the Zoologische Staatssammlung München and specimens newly collected from near the type locality. In addition, S. longisetosussp. nov., a new species that bears tergal keels like S. quadristriatus, is described from the Ryukyu Islands in Japan and Taiwan. Although the presence of four keels on tergites is unique to these two species, phylogenetic analyses using nuclear and mitochondrial markers showed that S. longisetosussp. nov. is not sister to S. quadristriatus. The obtained phylogeny indicates that the tergal longitudinal keels evolved in parallel within Scolopocryptops or that the presence of keels represents a plesiomorphic character of the clade containing these species.

Exploring hidden diversity: Molecular insights into the Leporinus species of the rivers of the Brazilian states of Maranhão and Piauí.

The present study delved into the world of hidden diversity by examining specimens identified as Leporinus piau from the river basins of the northern Brazilian states of Maranhão and Piauí. Using genetic analyses that combined data from three mitochondrial markers and one nuclear marker, the study identified two well-supported groups, reinforcing the findings of previous publications. The first group, found in samples from the Itapecuru, Mearim, Turiaçu, and Pericumã basins, in Maranhão, appears to represent a relatively ancient diversification and the possibility of concealed cryptic diversity. The second group, comprising specimens from the Parnaíba (Piauí) and Mearim (Maranhão) basins, appears to have resulted from a more recent process of diversification and has a close relationship with Leporinus friderici from the type locality. Our findings not only confirm the existence of a complex scenario of cryptic diversity in the genus Leporinus from the study basins but also underscore the taxonomic inconsistencies within this group of fish. This study offers a comprehensive analysis of the species diversity of the Maranhão and Piauí basins, which are critical regions for the conservation of Amazonian fish, providing valuable insights for the sustainable management and conservation of these fish.

1135 Classification of Temporal Lobe Epilepsy Anatomo-clinico-electrical Hypotheses: A Stereo EEG Study

INTRODUCTION: Temporal lobe epilepsy (TLE) has historically been divided into mesial and lateral (neocortical) TLE, but electrophysiological, semiological, and anatomical evidence indicate that the epileptogenic zone (EZ) and areas of propagation involve both temporal and extratemporal structures. Hypothesis-driven, structured interrogation is crucial for a successful stereo EEG (SEEG) exploration and subsequent successful surgical intervention. METHODS: 59 patients (ages 19-77) with drug-resistant TLE underwent SEEG at our institution from 2020-2022. We retrospectively reviewed each patient’s multidisciplinary discussions, history, imaging, and outcomes. We proposed four types of implantation hypotheses: temporal, temporal/basal/occipital, anterior perisylvian, and perisylvian. We quantitatively validated these types against anatomic coverage and semiology using unsupervised clustering and clinically by comparing classification to rates of successful localization of the epileptogenic zone (EZ) and seizure outcomes. RESULTS: Temporal (only) hypotheses were the least frequent (13.6%), followed by temporal/basal/occipital (25.4%), anterior perisylvian (30.5%), and perisylvian (30.5%). The hypotheses were not different in age at SEEG (p = 0.32), sex (p = 0.67), and handedness (p = 0.33). Frequent semiological features by type were: temporal – autonomic features, dÉjÀ vu; temporal/basal/occipital – visual and language disturbance; anterior perisylvian – oromotor; perisylvian – sensory manifestation. Clustering was validated against semiology (RI = 0.63) and lobar coverage (RI = 0.73). Successful localization of the EZ occurred in 79.7% and did not associate with hypothesis type (p = 0.22). Hypothesis type (p = 0.30) or EZ localization (p = 1.00) did not associate with the presence of an MRI lesion. 6-month Engel 1a rate was 71% and did not vary by hypothesis type (p = 0.29). CONCLUSIONS: The anatomo-clinico-electrical hypotheses in TLE must consider both temporal and extratemporal structures and not be limited by a medial vs. lateral TLE mindset. This proposed classification of TLE hypotheses can serve as starting point for multidisciplinary patient discussion as well as a tool to compare SEEG exploration and outcomes across centers.

Redescription of Pronematus ubiquitus (McGregor, 1932) (Acari, Iolinidae), description of two new species and redescription of two additional species with a review of and key to all Pronematus species

Pronematus ubiquitus (McGregor) is redescribed based on specimens collected at the type locality. Additionally, in a survey for natural enemies of Aculops lycopersici (Tryon), P. ubiquitus was found in most European countries where samples were gathered as well as in Morocco. Together with specimens available from museum collections and originating from Brazil, South Africa and Türkiye, the newly collected specimens were measured and morphologically compared with those from the type locality. Additionally, single female expansion lines were set-up with specimens from California (USA), Belgium, France, Italy, The Netherlands and Morocco, and molecular analysis were performed in order to construct a phylogenetic tree. The tree showed differences between origins, but this was assigned to intraspecific variation. A PCA analysis on morphological characters separated the Brazilian specimens from those of all other geographical origins. The Californian (USA) specimens grouped together, as did the Moroccan and all European specimens, but with overlap between the groups. The Brazilian specimens were described as a new species, P. brasiliensis n. sp. All other specimens were considered as P. ubiquitus. Furthermore, we searched for types of early described Pronematus species and studied P. rykei, P. karrooi and P. tenuisetosus types; the first two species were confirmed morphologically as a distinct Pronematus species while the latter belongs to the genus Pseudopronematulus. The morphological characteristics of specimens that were used for a recent redescription of P. rykei did not coincide with our redescription of the type. We transferred those specimens to the new species, P. juglandi sp. nov.

Catalog of Anaedus Blanchard, 1842 with nomenclatural notes (Coleoptera: Tenebrionidae: Lagriinae)

The genus Anaedus Blanchard, 1842 in the tribe Goniaderini Lacordaire, 1859 has experienced drastic genus-level change where seven other genera were subsumed as synonyms by Aalbu et al. (2023). That study addressed multiple nomenclatural issues including several replacement names, but did not provide a full species-group catalog. This study presents a full catalog for the 142 species-group names currently belonging to Anaedus and rectifies several nomenclatural issues missed within the previous study. The catalog includes full nomenclatural histories and type localities for all taxa. The following New Combinations are established: Anaedus keralensis (Kaszab, 1979), An. madrensis (Kaszab, 1979), An. philippinus (Schawaller, 1994), An. setosus (Kaszab, 1979), An. simillimus (Kaszab, 1979). The following New Replacement Names are established for the species listed in parentheses: Anaedus fairmairei Kanda & Johnston (replaces An. fulvipennis Fairmaire, 1889), An. pici Kanda & Johnston (replaces An. rufipes Pic, 192), An. pictus Kanda & Johnston (replaces Spinolyprops maculatus Kulzer, 1954), An. neorufescens Kanda & Johnston (replaces Aspisoma rufescens Pic, 1951).

Cantharis zapatai nom. nov., an overlooked species of Cantharis Linnaeus, 1758 from Central Spain (Coleoptera: Cantharidae)

Cantharis zapatai nom. nov. is proposed for Cantharis schrammi Pic, 1918, which is a primary homonym of Cantharis paulinoi var. schrammi Pic, 1907. The male of the species is redescribed, and the female is described here. The aedeagus and several external features are illustrated, and the species is compared with the closest relatives. Cantharis zapatai nom. nov. differs from its congeners by the characteristic spot in the vertex, yellowish pronotum and elytra, and black scutellum and appendages. The species is known from three localities of west central and central Spain (Iberian Peninsula), Guadalupe (Cáceres) (type locality), Puerto del Milagro (Toledo) and Fuencaliente (Ciudad Real). A key to the Iberian species of the genus Cantharis is provided.

Cayenniola albaserrata n. sp., a geographical relict from a Brazilian hotspot of subterranean biodiversity and the first troglobitic Priodesmini (Polydesmida: Chelodesmidae: Chelodesminae)

A new troglobitic species of Chelodesmidae, Cayenniola albaserrata n. sp., from the Água Clara cave system, Caatinga Domain, Bahia, Brazil is described. The new species is only the sixth known troglobitic chelodesmid, the first troglobitic species in the Priodesmini, and the first member of the tribe recorded from the state of Bahia. Unique among the Priodesmini, male C. albaserrata n. sp. possess greatly elongated pre-gonopodal tarsal claws and differ from the only congener, Cayenniola styliger (Jeekel, 1963), by a combination of gonopodal and somatic characters including classical troglomorphic traits such as a nearly unpigmented body and remarkably long antennae, legs, and tarsal claws. Cayenniola styliger is only known from the type locality in the Amazon rainforest of coastal French Guiana, suggesting that C. albaserrata n. sp. may represent a relictual species from the Caatinga Domain of Brazil. We provide ecological notes and evaluate the potential threats to the habitat of C. albaserrata n. sp., considering both the subterranean environment and the surrounding areas.  

Redescription of Arabella iricolor (Montagu, 1804) with descriptions of two new species from the United Kingdom and South Africa

Arabella iricolor (Montagu, 1804) was described with no diagnostic information for the characters used today to distinguish species within the genus. An updated description, together with genetic data, is provided using the holotype in conjunction with additional specimens collected at or near the type locality, to facilitate comparative analysis of other Arabella species and improve taxonomy within the genus. Arabella iricolor can be distinguished primarily through the long notopodial cirri that reach to or beyond the prechaetal lobes on chaetigers 1–9, in combination with unidentate maxilla I on both sides, four short digitiform pygidial cirri and gradually tapering ventralmost chaetae. The updated description and molecular information enabled the identification of a new species co-habiting with A. iricolor at the type locality and elsewhere. The new species, Arabella ampulliformis sp. nov., is characterised by two lateral pygidial lobes that extend into short cirri, appearing ampulliform in lateral view, in combination with a bifid left maxilla I, short left and long right maxilla II, short notopodial cirri and gradually tapering ventralmost chaetae. A new species from South Africa is also described, Arabella umgazanae sp. nov., distinguished through a bifid left maxilla I, short left and long right maxilla II, short notopodial cirri, two large lateral pygidial lobes and gradually tapering ventralmost chaetae along with additional characters relating to the chaetae, mandibles and maxillary apparatus. Problems surrounding the identification of Arabella species in South Africa are discussed in conjunction with details of the other species reported from the region. ZooBank: urn:lsid:zoobank.org:pub:9E60941E-7F95-4327-8884-5A56A5E7F309

Deep learning approaches for seizure video analysis: A review

Seizure events can manifest as transient disruptions in the control of movements which may be organized in distinct behavioral sequences, accompanied or not by other observable features such as altered facial expressions. The analysis of these clinical signs, referred to as semiology, is subject to observer variations when specialists evaluate video-recorded events in the clinical setting. To enhance the accuracy and consistency of evaluations, computer-aided video analysis of seizures has emerged as a natural avenue. In the field of medical applications, deep learning and computer vision approaches have driven substantial advancements. Historically, these approaches have been used for disease detection, classification, and prediction using diagnostic data; however, there has been limited exploration of their application in evaluating video-based motion detection in the clinical epileptology setting. While vision-based technologies do not aim to replace clinical expertise, they can significantly contribute to medical decision-making and patient care by providing quantitative evidence and decision support. Behavior monitoring tools offer several advantages such as providing objective information, detecting challenging-to-observe events, reducing documentation efforts, and extending assessment capabilities to areas with limited expertise. The main applications of these could be (1) improved seizure detection methods; (2) refined semiology analysis for predicting seizure type and cerebral localization. In this paper, we detail the foundation technologies used in vision-based systems in the analysis of seizure videos, highlighting their success in semiology detection and analysis, focusing on work published in the last 7 years. We systematically present these methods and indicate how the adoption of deep learning for the analysis of video recordings of seizures could be approached. Additionally, we illustrate how existing technologies can be interconnected through an integrated system for video-based semiology analysis. Each module can be customized and improved by adapting more accurate and robust deep learning approaches as these evolve. Finally, we discuss challenges and research directions for future studies.

Abstract 76: Correlated multi-scale 3D optical microscopy of tumor tissues

Abstract Three-dimensional (3D) optical microscopy in combination with advanced tissue clearing methods permits the interrogation of intact large-sized tumor tissues. There are many optical microscopy methods (e.g. light-sheet and confocal microscopy) offering 3D tumor images at varying levels of spatial resolution (e.g. organ, tissue, cell, and molecule level). However, it is a challenge to correlatively integrate various resolution 3D images obtained by different optical microscopy of tumor tissue. In this project, we developed a correlated multi-scale 3D optical microscopy method that enables the acquisition of macroscopic to microscopic spatial information from a single tumor tissue in 3D. Firstly, we used light sheet microscopy to image a whole large-sized, cleared tumor tissue and analyzed the results to identify regions of interests (ROIs). After defining ROIs in the 3D whole tumor image, we added a UV-activatable visible dye, spiropyran, in the agarose gel surrounding the cleared tumor and exposed the sample to a UV light sheet horizontally at the height (z-axis) of the tumor where the ROIs present. The activated dye showed ‘purple’ colored lines in the agarose gel and we physically marked the gel along the visible colored lines. We further sectioned the tumor at the ROI positions using a vibratome after reversing tissue clearing process. After immunofluorescence staining and aqueous-based tissue clearing, confocal microscopy allowed the localization of various cell types in the ROIs of tumor macrosections. To validate the method for multi-scale evaluation of cancer immunotherapy, we tested it with control and DMXAA-treated mouse mammary tumor tissues. We successfully acquired the 3D images of whole tumors by capturing autofluorescence signals with a 633 nm excitation laser and its matched emission filter. Based on the autofluorescence tumor images, we defined two ROIs for each control and treated tumor and performed optical marking and physical sectioning of the tumors as described above. Next, we stained the macrosections (400 µm thick) with DAPI, CK8-DL488, CD45-DL550, and ER-TR7-DL680 to visualize cancer, immune, and stromal cells in the ROIs at cellular resolution. We quantitatively analyzed the correlated multi-scale 3D image data for assessment of the effects of DMXAA treatment on the tumor microenvironment including eradiation of cancer cells, immune infiltration, and remodeling of tumor stroma. In summary, this new microscopy method will provide comprehensive spatial information of tumor tissues and benefit a broad cancer research field such as the discovery of new tumor biomarkers and the development of effective cancer therapies. Citation Format: Jingtian Zheng, Steve Seung-Young Lee. Correlated multi-scale 3D optical microscopy of tumor tissues [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 76.

Abstract 3876: A spatial transcriptomic study of a triple-negative breast cancer (TNBC) patient-derived xenograft (PDX) model of residual disease refractory to conventional chemotherapy

Abstract Combating chemotherapy resistance in TNBC is critical to improving quality of care and reducing fatality. To understand chemoresistance, it has been proposed that the spatial interactions between cell types in the tumor microenvironment (TME) could offer insights into the differential response to therapy and metastatic potential. Thus, this study utilizes spatially resolved transcriptomics (SRT) to profile the spatial interactions in TNBC TME. With the goal of understanding chemoresistance and providing a proof-of-concept for new technology, we launched a longitudinal SRT study of a TNBC PDX of residual disease before, during, and after adriamycin and cyclophosphamide (AC) treatment (Tx). SRT by 10X Visium was performed on Veh, AC-residual tumor (21 d post-Tx), and AC-regrown tumor (50 d post-Tx when tumors regrew). This study is divided into two parts. 1. Due to the lack of specialized tools for processing xenograft reads from SRT, we developed the Xenomake pipeline, which combines xenograft sorting and spatial barcode demultiplexing to assign reads into the host and graft organisms per spatial spot. It permits clustering the spots into stroma-rich (mouse), and epithelial-rich (human) regions. We show that it can find differential cytokines in the stroma (S) and epithelium (E), and finding SS, EE, and SE interactions. 2. Although using PDX necessitates immune-compromised mice, several types of stromal populations are present and analyzable. Thus, using Xenomake, we inferred the localization of stromal cell types in Visium spots including cancer associated fibroblasts (CAF), macrophages (MP), endothelial (ENDO), monocytes, and perivascular cells. We compared the spatial localization profiles (SLP) of stromal cell types across samples. With human reads, we computed the spatial pathway activity map (SPAM) for HALLMARK pathways. We correlated SPAM with stroma cell type SLP to survey stroma-epithelial interactions. Stroma cells are distributed in the tumor periphery in vehicle and AC50, while in AC21 there is a notable increase in stroma abundance and stroma infiltration within tumor mass. SLP of MP (Cd68+ and Csf1r+) is correlated with ENDO (Pecam1+), and CAF (Acta2+ and Pdgfrb+). Additionally, all 3 cell types are correlated with Vim and Cd44 expression. Although all samples show enrichment of MP, ENDO, and CAF, they interact differently with pathway activities of adjacent epithelial cells. In vehicle and AC50, the 3 cell types are colocalized with OXPHOS, MYC targets, E2F pathway, while in AC21, a switch to colocalization with EMT is observed. Further, hypoxia response and glycolysis display anti-correlation with stroma cell types, meaning that these pathway activities are further away from stroma and occupy distinct territories. The results suggest stroma-tumor metabolic crosstalk and ways of targeting residual disease. Citation Format: Benjamin Strope, Katherine Pendleton, William Bowie, Gloria Echeverria, Qian Zhu. A spatial transcriptomic study of a triple-negative breast cancer (TNBC) patient-derived xenograft (PDX) model of residual disease refractory to conventional chemotherapy [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 3876.

Abstract 196: In vitro modeling of pediatric solid tumor lung metastases

Abstract Metastasis remains the main cause of death in pediatric cancer patients with the lung being one of the most common affected organs. Our inability to cure these patients is largely due to insufficient knowledge about tumor and metastatic niche plasticity, while existing models are not fully effective in mirroring the response seen in clinical setting. Our goal is to overcome these limitations by establishing in vitro lung metastasis models using tumor/lung organoid co-cultures to study lung infiltration of pediatric solid tumors. We successfully established patient-derived lung organoids from pediatric lung tissue and characterized them according to the presence and the localization of the respective lung epithelial cell types. Co-culture conditions of lung organoids with PDX-derived Ewing sarcoma and osteosarcoma cells were optimized and models established, while the establishment of models for other pediatric solid tumor entities is ongoing. We have observed infiltration of the lung organoids by tumor cells, and our preliminary findings suggest distinct patterns of infiltration among different tumor entities. Furthermore, we have performed single-cell RNA sequencing analysis on these co-cultures in comparison to the parental lung organoids and tumor cells, aiming to uncover the specific signaling pathways activated in the lung metastatic niche in response to tumor cell invasion. Additionally, experiments using conditioned medium suggest that the lung organoid secretome is sufficient to induce homing of osteosarcoma and Ewing sarcoma cells to the organoids, with the CXCL12/CXCR4 signaling axis as a prime candidate driver. To ascertain the extent to which our in vitro model recapitulates the in vivo lung metastatic niche, we performed spatial transcriptomics (using VISIUM/10X Genomics) on formalin-fixed paraffin-embedded (FFPE) tissue blocks of paired primary tumors and lung metastasis samples for Ewing sarcoma and osteosarcoma. Comprehensive data analysis is currently ongoing, which will instruct a stepwise incorporation of additional factors into our modular organoid co-culture model, resulting in a better representation of the lung metastatic niche. Further, the analysis of patient-derived material will elucidate the spatial organization of solid tumor lung metastases and contribute to the identification of signaling pathways implicated in lung infiltration. In conclusion, our study not only unravels the complexities of pediatric solid tumor metastasis, but also lays the foundation for exploring the anti-metastatic potential of pathway-specific compounds targeting tumor/lung interactions using the established in vitro lung metastasis models. This study is supported by grant 35353-B of the Austrian Science Fund. Citation Format: Martha Zylka, Christoph Hafemeister, Lukas Watzke, Ulrike Mann, Didier Surdez, E. Alejandro Sweet-Cordero, Bernadette Liegl-Atzwanger, Matthias Dettmer, Matthias Farlik, Florian Halbritter, Martin Metzelder, Heinrich Kovar, Branka Radic-Sarikas. In vitro modeling of pediatric solid tumor lung metastases [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 196.