Medical Genetics Commons^™

Therapeutic Targeting Of Syndecan-1 Axis Overcomes Acquired Resistance To Kras-Targeted Therapy In Gastrointestinal Cancers, Madelaine S Theardy, Mitsunobu Takeda, Alexey Sorokin, Shuaitong Chen, Zecheng Yang, Xiaofei Wang, Preeti Kanikarla, Oluwadara Coker, Phuoc Nguyen, Yongkun Wei, Jun Yao, Liang Yan, Yanqing Jin, Yiming Cai, Masakatsu Paku, Ziheng Chen, Kara Z Li, Francesca Citron, Hideo Tomihara, Sisi Gao, Angela K Deem, Jun Zhao, Huamin Wang, Samir Hanash, Ronald A Depinho, Anirban Maitra, Giulio F Draetta, Haoqiang Ying, Scott Kopetz, Wantong Yao

Faculty, Staff and Student Publications

The therapeutic benefit of recently developed mutant KRAS (KRAS∗) inhibitors remains limited by the rapid onset of resistance. Here, we aim to delineate mechanisms underlying acquired resistance and identify actionable targets for overcoming this clinical challenge. Previously, we identified syndecan-1 (SDC1) as a key effector for pancreatic cancer progression whose surface expression is driven by KRAS∗. By leveraging both pancreatic and colorectal cancer models, we show that surface SDC1 expression initially diminishes upon KRAS∗ inhibition but recovers in tumor cells that bypass KRAS∗ dependency. Mechanistically, we reveal that YAP1 activation drives the recovery of SDC1 surface localization to enhance macropinocytosis-mediated …

Mathematical Modeling And Association Analysis Decipher The Impact Of The Gut Microbiome On Cancer Immunotherapy, Andreas G Hadjigeorgiou, Constantinos Harkos, Aditya K Mishra, Golnaz Morad, Sarah B Johnson, Nadim J Ajami, Jennifer A Wargo, Lance L Munn, Triantafyllos Stylianopoulos, Rakesh K Jain

Faculty, Staff and Student Publications

The gut microbiome has emerged as a key regulator of response to cancer immunotherapy. However, a better understanding of the underlying mechanisms by which the microbiome influences immunotherapy is needed to identify strategies to optimize outcomes. To this end, we developed a mathematical model to obtain insights into the effect of the microbiome on the immune system and immunotherapy response. This model was based on (i) gut microbiome data derived from preclinical studies, (ii) mathematical modeling of the antitumor immune response, (iii) association analysis of microbiome profiles with model-predicted immune profiles, and (iv) statistical models that correlate model parameters with …

Ribosome Deficiency Induces Salmonella Filamentation Within Host Cells, Zhihui Lyu, Cierra Wilson, Kalyn Weiss, Spencer Lewis, Kurt Fredrick, William Margolin, Jiqiang Ling

Faculty, Staff and Student Publications

The ribosome is the central hub for protein synthesis and is heavily targeted by antibiotics. Ribosomal mutations, antibiotic treatment, and nutrient starvation can alter translational efficiency and lead to stressed cells. Ribosome deficiency plays a critical role in stress responses and disease progression; yet, how it affects bacteria-host interactions remains poorly understood. In this study, we show that a ribosome-deficient strain exhibits a surprising morphological change from rod shape to filamentous in Salmonella cells growing inside host macrophages. Such filamentation depends on an acidic condition within macrophages and in a defined medium mimicking macrophage conditions. Further genetic analyses revealed that …

Non-Isolated Tetralogy Of Fallot (Tof+): Exome Sequencing Efficacy And Phenotypic Expansions, Julia Volpi, Xiaonan Zhao, Nichole Owen, Tia Evans, Muriel Holder-Espinasse, Nayana Lahiri, Eleanor Sherlock, Gemma Poke, Jeroen Breckpot, Koen Devriendt, Bjorn Cools, Alfredo Brusco, Giovanni Battista Ferrero, Enrico Grosso, Pradeep Vasudevan, Sara Loddo, Antonio Novelli, Maria Cristina Digilio, Aafke Engwerda, Marrit Hitzert, Alison Male, Lucy Bownass, Ruth Newbury-Ecob, Zosia Miedzybrodzka, Ruth Armstrong, Sally Ann Lynch, Gunnar Houge, Shiyi Xiong, Seema R Lalani, Jill A Rosenfeld, Pamela N Luna, Chad A Shaw, Daryl A Scott

Faculty, Staff and Students Publications

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart defect (CHD). TOF may present in isolation or in conjunction with one or more non-cardiac congenital anomalies or neurodevelopmental disorders (TOF+). Uncertainty regarding the efficacy of various genetic testing strategies, and an incomplete understanding of the genetic causes of TOF+, may lead to hesitancy in recommending genetic testing, particularly, clinical exome sequencing (cES). Here, we analyzed cES data from 131 individuals with TOF+. A definitive or probable diagnosis was made for 31 individuals, yielding a diagnostic rate of 23.6% (31/131). One individual received three diagnoses. Commercially available CHD panels …

Extracellular Vesicles For Clinical Diagnostics: From Bulk Measurements To Single-Vesicle Analysis, Hai Linh Tran, Wenshu Zheng, David A Issadore, Hyungsoon Im, Yoon-Kyoung Cho, Yuanqing Zhang, Dingbin Liu, Yang Liu, Bo Li, Fei Liu, David Tai Wai Wong, Jiashu Sun, Kun Qian, Mei He, Meihua Wan, Yong Zeng, Ke Cheng, Tony Jun Huang, Daniel T Chiu, Luke P Lee, Lei Zheng, Andrew K Godwin, Raghu Kalluri, Steven A Soper, Tony Y Hu

Faculty, Staff and Student Publications

Extracellular vesicles (EVs) play a crucial role in intercellular communication, signaling pathways, and disease pathogenesis by transporting biomolecules such as DNA, RNA, proteins, and lipids derived from their cells of origin, and they have demonstrated substantial potential in clinical applications. Their clinical significance underscores the need for sensitive methods to fully harness their diagnostic potential. In this comprehensive review, we explore EV heterogeneity related to biogenesis, structure, content, origin, sample type, and function roles; the use of EVs as disease biomarkers; and the evolving landscape of EV measurement for clinical diagnostics, highlighting the progression from bulk measurement to single vesicle …

Hippocampal Avoidance During Prophylactic Cranial Irradiation For Patients With Small Cell Lung Cancer: Randomized Phase Ii/Iii Trial Nrg-Cc003, Vinai Gondi, Stephanie L Pugh, Minesh P Mehta, Jeffrey S Wefel, Wolfgang A Tomé, Alexander Y Sun, John Grecula, Kristin J Redmond, Shannon Fogh, Laurie Gaspar, Andre Konski, Joseph Bovi, Clifford G Robinson, Benjamin Corn, Gregory M Videtic, Benjamin H Lok, Harold A Yoon, John H Heinzerling, Albert S Denittis, Ronald C Mcgarry, Kiran Devisetty, Vijayananda Kundapur, Abraham J Wu, Edward C Mccarron, Isabelle Thibault, Edmund L Simon, Andrew M Baschnagel, Samir Narayan, Jondavid Pollock, Rebecca Paulus, Lisa A Kachnic

Faculty, Staff and Student Publications

Purpose: Hippocampal avoidance (HA) during therapeutic whole-brain radiotherapy reduces the risk of neurocognitive function (NCF) toxicity in patients with brain metastasis. This trial hypothesized that HA during prophylactic cranial irradiation (PCI) in patients with small cell lung cancer (SCLC) leads to noninferior intracranial relapse (ICR) and reduction in NCF toxicity.

Methods: This randomized phase II/III trial enrolled patients with SCLC, no brain metastases, and response to chemotherapy. The primary end points were 12-month ICR (noninferiority design, randomized phase II) and 6-month Hopkins Verbal Learning Test-Revised (HVLT-R) Delayed Recall (DR) failure (phase III). Secondary end points were failure in any NCF …

Keap1 And Stk11/Lkb1 Alterations Enhance Vulnerability To Atr Inhibition In Kras Mutant Non-Small Cell Lung Cancer, Ana Galan-Cobo, Natalie I Vokes, Yu Qian, David Molkentine, Kavya Ramkumar, Alvaro G Paula, Marlese Pisegna, Daniel J Mcgrail, Alissa Poteete, Sungnam Cho, Minh Truong Do, Amirali Karimi, Yifan Kong, Anisha Solanki, Ankur Karmokar, Nicolas Floc'h, Adina Hughes, Rebecca Sargeant, Lucy Young, Li Shen, Gozde Kar, Caezaan Keshvani, Claudio Arrechedera, Sharia Hernandez, Katharina Schlacher, Jing Wang, Sonia Iyer, James Conway, Mohamed Reda Keddar, Marta Milo, Ilario De Toma, Susan E Critchlow, J Carl Barrett, Jan Cosaert, Alan Lau, Viia Valge-Archer, Lauren A Byers, Simon T Barry, John V Heymach

Faculty, Staff and Student Publications

KRAS mutations frequently co-occur with alterations in STK11/LKB1 and/or KEAP1, defining an aggressive subset of lung cancers resistant to immuno- and chemotherapy. While LKB1 loss is associated with vulnerability to DNA damage response-based therapies, the impact of KEAP1 alterations remains unknown. We demonstrate that KEAP1-NRF2 pathway drives a compensatory modulation of ATR-CHK1 signaling, enhancing vulnerability to ATR inhibitors (ATRi), particularly in the setting of increased replication stress associated with LKB1 loss. ATRi shows enhanced anti-tumor activity in LKB1 and/or KEAP1-deficient non-small cell lung cancer (NSCLC) models and synergizes with gemcitabine. ATRi also enhances antitumor immunity and mitigates the immunosuppressed phenotype …

Mutant P53 Confers Chemoresistance By Activating Kmt5b-Mediated Dna Repair Pathway In Nasopharyngeal Carcinoma, Haidan Luo, Mo-Fan Huang, An Xu, Donghui Wang, Julian A Gingold, Jian Tu, Ruoyu Wang, Zijun Huo, Yen-Ting Chiang, Kuang-Lei Tsai, Jie Su, Danielle A Bazer, Mien-Chie Hung, Canmao Xie, Yubiao Guo, Dung-Fang Lee, Huiling Yang, Ruiying Zhao

Faculty, Staff and Student Publications

Nasopharyngeal carcinoma (NPC), a malignancy arising from the nasopharyngeal epithelium, is common in the east and southeast area of Asia. Treatments for locally advanced and recurrent NPC include chemotherapy (usually combined with 5-Fluorouracil, 5-FU) and radiotherapy, but response is limited due to chemo-resistance. p53 mutation is a critical factor for 5-FU resistance in some cancers, but its role in NPC chemo-resistance remains unclear. Here, we demonstrate that p53(R280T), a common p53 somatic mutation found in multiple NPC tumor samples, induces gain-of-function upregulation of DNA repair genes which leads to 5-FU resistance in NPC. p53(R280T) specifically upregulates the expression of DNA …

Rare Variants In Bmal1 Are Associated With A Neurodevelopmental Syndrome, Vishnu Anand Cuddapah, Dechun Chen, Bumsik Cho, Rebecca Moore, Mohnish Suri, Hana Safraou, Frederic Tran-Mau-Them, Ashley Wilson, Jacqueline Odgis, Atteeq U Rehman, Carol Saunders, Shiva Ganesan, Vaidehi Jobanputra, Stephen W Scherer, Ingo Helbig, Amita Sehgal

Duncan NRI Faculty and Staff Publications

Children with neurodevelopmental disorders exhibit highly penetrant sleep and circadian dysfunction, but the underlying mechanisms are unclear. We asked whether a subset of individuals with neurodevelopmental disorders might have genetic variants in genes known to drive circadian rhythms. Through international collaboration, we identified ten individuals with very rare genetic variants in BMAL1, a core component of the molecular clock. These individuals exhibited overlapping signs and symptoms including developmental delay, autism spectrum disorder, and variably penetrant marfanoid features. We functionally tested the identified BMAL1 variants in cell culture and in vivo and found disrupted BMAL1 function. These findings demonstrate that …

Rapid Dissection And Dissociation Of The Mouse Olfactory Epithelium For Single-Nucleus Suspensions, Benjamin D W Belfort, Anthony M Insalaco, Claude C Chew, Johnathan D Jia, Julia Younis, Benjamin R Arenkiel

Duncan NRI Faculty and Staff Publications

The murine olfactory epithelium is the initial entry point of the olfactory system, housing various cell types that include olfactory sensory neurons, their regenerating progenitors, and support cells. Olfactory sensory neurons transduce chemical odorants into neural signals, yet the mechanisms underlying how these cells develop and turnover, create synapses with the olfactory bulb, and regulate their odorant receptors remain areas of intense study. Located on the dorsal aspect of the nasal cavity, the olfactory epithelium adheres to intricate bony structures known as turbinates. This anatomy poses unique challenges for its extraction and dissociation, especially in the context of preparing viable …

Acquired Resistance In Cancer: Towards Targeted Therapeutic Strategies, Alice Soragni, Erik S Knudsen, Thomas N O'Connor, Cristina E Tognon, Jeffrey W Tyner, Beatrice Gini, Donghwa Kim, Trever G Bivona, Xingxing Zang, Agnieszka K Witkiewicz, David W Goodrich, Dadi Jiang, Seth T Gammon, Christopher D Willey, Paul C Boutros, Vlad C Sandulache, Abdullah A Osman, Jeffrey N Myers, Kamiya Mehla, Pankaj K Singh, Keith S Chan, Hongbo Gao, Himangi Marathe

Faculty, Staff and Student Publications

Development of acquired therapeutic resistance limits the efficacy of cancer treatments and accounts for therapeutic failure in most patients. How resistance arises, varies across cancer types and differs depending on therapeutic modalities is incompletely understood. Novel strategies that address and overcome the various and complex resistance mechanisms necessitate a deep understanding of the underlying dynamics. We are at a crucial time when innovative technologies applied to patient-relevant tumour models have the potential to bridge the gap between fundamental research into mechanisms and timing of acquired resistance and clinical applications that translate these findings into actionable strategies to extend therapy efficacy. …

De Novo And Inherited Variants In Ddx39b Cause A Novel Neurodevelopmental Syndrome, Kevin T A Booth, Sharayu V Jangam, Martin M C Chui, Kayla Treat, Lorenzo Graziani, Alessia Soldano, Yao Ruan, Jeffrey Wan-Hei Hui, Kerry White, Celanie K Christensen, Ty Lynnes, Shinya Yamamoto, Oguz Kanca, Mandy H Y Tsang, Sally A Lynch, Sureni V Mullegama, Julia Baptista, Daniela Iancu, Shelagh K Joss, Sandra Y Y Wong, Christopher C Y Mak, Anna K Y Kwong, Hugo J Bellen, Erin Conboy, Remo Sanges, Anskar Yu-Hung Leung, Michael F Wangler, Brian H Y Chung, Francesco Vetrini

Duncan NRI Faculty and Staff Publications

DDX39B is a conserved member of the DEAD-box family of ATP-dependent RNA helicases, critical in mRNA metabolism across eukaryotes. DDX39B is also a core component of the TRanscription-EXport (TREX) super protein complex, and recent studies have highlighted the important role of its subunits in neurodevelopmental disorders. Here, we describe six individuals from five families, four harbouring de novo missense variants in DDX39B and one with an inherited splicing variant, presenting with variable developmental delay, congenital hypotonia, epilepsy, short stature, skeletal abnormalities, dysmorphic features and microcephaly in three patients.

3D molecular modelling predicts these variants would alter protein structure. In vitro …

Folliculin Depletion Results In Liver Cell Damage And Cholangiocarcinoma Through Mit/Tfe Activation, Bruno Maria Custode, Francesco Annunziata, Felipe Dos Santos Matos, Valentina Schiano, Veronica Maffia, Milena Lillo, Rita Colonna, Rossella De Cegli, Andrea Ballabio, Nunzia Pastore

Duncan NRI Faculty and Staff Publications

Mutations in the tumor suppressor gene Folliculin (FLCN) are responsible for Birt-Hogg-Dube’ (BHD) syndrome, a rare inherited condition that predisposes affected individuals to skin tumors, pulmonary cysts, and kidney tumors. FLCN regulates key cellular pathways, including TFEB, TFE3, and mTORC1, which are critical for maintaining cell homeostasis. Loss of FLCN leads to both hyperactivation of mTORC1 and constitutive activation of TFEB and TFE3, contributing to tumorigenesis. While previous studies showed that Flcn liver-specific conditional knockout (FlcnLiKO) mice are protected from developing liver fibrosis and damage upon high-fat diet exposure, the potential role of FLCN loss in liver carcinogenesis …

The Glycosyltransferase Poglut1 Regulates Muscle Stem Cell Development And Maintenance In Mice, Soomin Cho, Emilia Servián-Morilla, Victoria Navarro, Beatriz Rodriguez-Gonzalez, Youxi Yuan, Raquel Cano, Arjun A Rambhiya, Radbod Darabi, Robert S Haltiwanger, Carmen Paradas, Hamed Jafar-Nejad

Faculty, Staff and Students Publications

Mutations in protein O-glucosyltransferase 1 (POGLUT1) cause a recessive limb-girdle muscular dystrophy (LGMDR21) with reduced satellite cell number and NOTCH1 signaling in adult patient muscles and impaired myogenic capacity of patient-derived muscle progenitors. However, the in vivo roles of POGLUT1 in the development, function, and maintenance of satellite cells are not well understood. Here, we show that conditional deletion of mouse Poglut1 in myogenic progenitors leads to early lethality, postnatal muscle growth defects, reduced Pax7 expression, abnormality in muscle extracellular matrix, and impaired muscle repair. Poglut1-deficient muscle progenitors exhibit reduced proliferation, enhanced differentiation, and accelerated fusion into myofibers. Inducible loss …

Mx1-Labeled Pulp Progenitor Cells Are The Main Contributors Of Odontoblast And Dentin Regeneration In Murine Molars, Dongwook Yang, Youngjae Jeong, Laura Ortinau, Jea Giezl Solidum, Dongsu Park

Faculty, Staff and Students Publications

Regeneration of dentin and odontoblasts from dental pulp progenitor cells is essential for the maintenance of permanent tooth. However, the in vivo identity of endogenous pulp progenitor cells and how they contribute to reparative dentinogenesis remain elusive. Here we show that comparative single-cell analysis of pulp cells before and after molar eruption reveal that endogenous pulp progenitor cells are enriched in coronal papilla-like cells with Mx1-Cre and Cxcl12–GFP expression. Further, lineage tracing and fluorescence-activated cell sorting analysis indicated that Mx1-labeled (Mx1+) pulp cells include long-term repopulating progenitor cells with higher expression of stem cell markers. Notably, …

Nanotechnology For Immuno-Oncology, Adam J Grippin, Daeyong Lee, Eileen E Parkes, Wen Jiang, Betty Y S Kim

Faculty, Staff and Student Publications

Although the first generation of cancer immunotherapeutics produced unprecedented improvements in clinical outcomes for individuals with cancer, novel strategies to increase treatment specificity, delivery efficiency and pharmacokinetics are still needed. In this Review, we describe the potential advantages and current limitations of nanomaterials for cancer immunotherapy and highlight rational uses of nanosystems to generate potent and durable antitumor immune responses. We close with a review of the current state of clinical development of nanomedicine for cancer immunotherapy.

Human And Mouse Alzheimer's Seeds Differentially Affect Amyloid Deposition And Microglia-Dependent Plaque Response In Aged Mice, Juana Andreo-Lopez, Cristina Nuñez-Diaz, Kelly Do Huynh, Marie Minh Thu Nguyen, Celia Da Cunha, Francisco J Cantero-Molina, Cynthia Campos-Moreno, Stefania Zimbone, Francesco Bellia, Maria Laura Giuffrida, Laura Trujillo-Estrada, Juan Antonio Garcia-Leon, Miriam Bettinetti-Luque, Nazaret Gamez, Catalina Valdes, Rodrigo Morales, Stefania Forner, Alessandra C Martini, Antonia Gutierrez, Frank M Laferla, David Baglietto-Vargas

Faculty, Staff and Student Publications

Alzheimer's disease (AD) is a complex neurodegenerative proteinopathy in which Aβ and tau misfold and aggregate into entities that structurally unsettle native proteins, mimicking a prion-like or "seeding" process. These Aβ and tau "seeds" can arrange in different conformations or strains that might display distinct pathogenic properties. Furthermore, recent evidence suggests that microglia play a key role in the amyloidogenic event and can modulate the propagation and aggregation processes. Here, we employed histological and molecular approaches to determine whether seeds from human AD brains compared to those from transgenic mice (3xTg-AD) are more prone to induce Aβ and tau aggregates …

12/15-Lipooxygenase Inhibition Reduces Microvessel Constriction And Microthrombi After Subarachnoid Hemorrhage In Mice, Ari Dienel, Sung Ha Hong, Hussein A Zeineddine, Sithara Thomas, Shafeeque C M, Dania A Jose, Kiara Torres, Jose Guzman, Andrew Dunn, P Kumar T, Gadiparthi N Rao, Spiros L Blackburn, Devin W Mcbride

Faculty, Staff and Student Publications

Impaired cerebral circulation, induced by blood vessel constrictions and microthrombi, leads to delayed cerebral ischemia after subarachnoid hemorrhage (SAH). 12/15-Lipooxygenase (12/15-LOX) overexpression has been implicated in worsening early brain injury outcomes following SAH. However, it is unknown if 12/15-LOX is important in delayed pathophysiological events after SAH. Since 12/15-LOX produces metabolites that induce inflammation and vasoconstriction, we hypothesized that 12/15-LOX leads to microvessel constriction and microthrombi formation after SAH, and thus, 12/15-LOX is an important target to prevent delayed cerebral ischemia. SAH was induced in C57BL/6 and 12/15-LOX−/− mice of both sexes by endovascular perforation. Expression of 12/15-LOX was assessed …

Inhibition Of Methylthioadenosine Phosphorylase Protects From Experimental Acute Kidney Injury, Afaf Saliba, Yidong Chen, Jonathan W Nelson, Abhinav Vetcha, Wei Wei Wang, Li Kang, Nagarjunachary Ragi, Soumya Maity, Hamid Rabb, W Brian Reeves, Kumar Sharma

Faculty, Staff and Student Publications

Methylthioadenosine phosphorylase (MTAP) is a key enzyme in purine metabolism that may influence cellular responses to injury. We evaluated the effects of prophylactic MTAP inhibition in mouse models of ischemia-reperfusion and cisplatin-induced acute kidney injury (AKI). MTAP inhibition was confirmed by accumulation of methylthioadenosine (MTA). Treated mice showed reduced renal injury and decreased tubular damage. Transcriptomic analysis revealed protection from inflammatory and stress pathways, while maintaining oxidative phosphorylation, fatty acid metabolism, and epithelial integrity-related genes. Analysis of human single-cell RNA-seq data from the Kidney Precision Medicine Project indicated that MTAP is highly expressed in kidney injury marker-positive adaptive proximal tubule …

Orp2 Regulates Free Cholesterol Accumulation In Hepatocytes During Mash, Jin Wu, Yudi Zhao, Liwen Qiu, Qiaoli Chen, Xiaowei Wang, Jingwen Gu, Yan Liang, Yingjie Zhang, Hong-Yu Wang, Yang Liu, Xiaoqin Wu, Shuai Chen, Feng-Jung Chen, Mingming Gao, Hongyuan Yang

Faculty, Staff and Student Publications

Background: Cholesterol crystals in hepatocytes are known to strongly associate with human metabolic dysfunction-associated steatohepatitis. However, it remains unclear which molecular pathway(s) regulates free cholesterol accumulation and the formation of cholesterol crystals in hepatocytes. In cultured cell lines, oxysterol-binding protein-related protein 2 (ORP2) functions to deliver cholesterol to the plasma membrane from endosomal compartments.

Methods: Here, we generated liver-specific ORP2 knockout (ORP2-LKO) mice and characterized their metabolic phenotypes on chow and high-fat diet.

Results: The ORP2-LKO mice developed much more severe hepatic steatosis than floxed control mice after high-fat diet feeding. They also demonstrated more severe liver inflammation and damage. …

Mitophagy’S Impacts On Cancer And Neurodegenerative Diseases: Implications For Future Therapies, Jason Huang, Vincent Truong Pham, Shaozi Fu, Gang Huang, Ya-Guang Liu, Lei Zheng

Faculty, Staff and Student Publications

Substantial evidence supports an inverse relationship between cancer and neurodegenerative diseases (NDDs), but few studies investigate the biological mechanisms underlying this phenomenon. While previous explanations-such as inflammation, reactive oxygen species (ROS), genetic mutations, and cell death-remain significant, they ultimately converge on mitophagy. This review identifies mitophagy as a pivotal factor in the development of both cancer and NDDs, while also evaluating specific mechanisms and processes to clarify how mitophagy connects these opposing disease trajectories. By examining these factors, we aim to uncover the underlying mechanisms that explain the inverse relationship between cancer and NDDs, which will help develop therapeutic strategies …

Gd3 Synthase Drives Resistance To P53-Induced Apoptosis In Breast Cancer By Modulating Mitochondrial Function, Vivek Anand, Fouad El-Dana, Natalia Baran, Jenny Borgman, Zheng Yin, Hong Zhao, Stephen T Wong, Michael Andreeff, V Lokesh Battula

Faculty, Staff and Student Publications

TP53 mutations are common in breast cancer (BC) and are associated with poor prognosis. GD3 synthase (GD3S/ST8SIA1), a gene associated with breast cancer stem cells, is upregulated in tumors with p53 mutations. However, the functional relationship between GD3S and p53 is unknown. Here, we show that GD3S levels are highest in breast tumors with specific p53 mutations. Functional studies revealed that wild-type (WT) p53 inhibits GD3S expression, whereas mutation in p53 enhances GD3S expression by upregulating GD3S promoter activity. Moreover, we found that GD3S inhibits wild-type p53-induced apoptosis in BC cells, while BC cells harboring gain-of-function p53 mutations are dependent …

Sleep Drive, Not Total Sleep Amount, Increases Seizure Risk, Vishnu Anand Cuddapah, Cynthia T Hsu, Fernanda Valle Sirias, Yongjun Li, Hrishit M Shah, Christopher Saul, Samantha Killiany, Camilo Guevara, Joy Shon, Zhifeng Yue, Gabrielle L Gionet, Mary E Putt, Amita Sehgal

Duncan NRI Faculty and Staff Publications

Sleep loss has been associated with increased seizure risk since antiquity. Using automated video detection of spontaneous seizures in Drosophila epilepsy models, we show that seizures worsen only when sleep restriction raises homeostatic "sleep drive," not simply when total sleep amount falls. This is supported by the paradoxical finding that acute activation of sleep-promoting circuits worsens seizures, because it increases sleep drive without changing sleep amount. Sleep-promoting circuits become hyperactive after sleep loss and are associated with increased whole-brain activity. During sleep restriction, optogenetic inhibition of sleep-promoting circuits to reduce sleep drive protects against seizures. Downregulation of the 5HT1A serotonin …

Melanoma Antigens In Pediatric Medulloblastoma Contribute To Tumor Heterogeneity And Species-Specificity Of Group 3 Tumors, Rebecca R J Collins, Rebecca R Florke Gee, Sima Tozandehjani, Tara Bayat, Maria Camila Hoyos Sanchez, Juan Sebastian Solano Gutierrez, Barbara Breznik, Anna K Lee, Samuel T Peters, Jon P Connelly, Shondra M Pruett-Miller, Martine F Roussel, Dinesh Rakheja, Heather S Tillman, Patrick Ryan Potts, Klementina Fon Tacer

Faculty, Staff and Student Publications

Medulloblastoma (MB) is the most malignant childhood brain cancer. Group 3 MB (G3 MB) subtype accounts for about 25% of MB and is associated with the worst outcomes. Herein, we report that more than half of G3 MB tumors express melanoma antigens (MAGEs), which are potential prognostic and therapeutic markers. MAGEs are cancer-testis antigens, aberrantly expressed in several adult cancers, and associated with poorer prognosis and therapy resistance; however, their role in pediatric cancers is mostly unknown. This study aimed to determine whether MAGEs are activated and important in pediatric MB. We obtained formalin-fixed paraffin-embedded tumor samples of 34 patients, …

Human Ipsc-Based Breast Cancer Model Identifies S100p-Dependent Cancer Stemness Induced By Brca1 Mutation, Jingxin Liu, Cai Zhao, Jiahao Chen, Pengguihang Zeng, Qingjian Li, Ranran Dai, Xingqiang Lai, Wenqian Song, Jianing Chen, Xixi Zhu, Xinyi Liu, Jun Sun, Jia Wang, Peihang Fang, Tengfei Wang, Wenjie Chen, Diana Guallar, Nan Cao, Jianli Zhao, Shicheng Su, Andy Peng Xiang, Yi Arial Zeng, Jie Li, Junchao Cai, Dung-Fang Lee, Jinxin Bei, Yongliang Huo, Hai Hu, Shengbao Suo, Dong-Feng Huang, Jin Bai, Junjun Ding

Faculty, Staff and Student Publications

Breast cancer is the most common malignancy in females and remains the leading cause of cancer-related deaths for women worldwide. The cellular and molecular basis of breast tumorigenesis is not completely understood partly due to the lack of human research models which simulate the development of breast cancer. Here, we developed a method for generating functional mammary-like cells (MCs) from human-induced pluripotent stem cells (iPSCs). The iPSC-MCs closely resemble human primary MCs at cellular, transcriptional, and functional levels. Using this method, a breast cancer model was generated using patient-derived iPSCs harboring germline

The Histone H3 Lysine 36 Demethylase Kdm2a/Fbxl11 Controls Polycomb-Mediated Gene Repression And Germ Cell Development In Male Mice, Michael T Bocker, Grigorios Fanourgakis, Kristie Wetzel, Pavel A Komarov, Hélène Royo, Alexia Rohmer, Sunwoo Chun, Ching-Yeu Liang, Hubertus Kohler, Taiping Chen, Xiaohong Mao, Mark A Labow, Reginald A Valdez, Michael B Stadler, Dirk G De Rooij, Paola Capodieci, John Tallarico, Antoine H F M Peters, Thomas B Nicholson

Faculty, Staff and Student Publications

KDM2A/FBXL11 is a Jumonji-domain containing lysine demethylase catalyzing the removal of mono- and di-methyl modifications of histone H3 lysine 36 (H3K36me1/2). While Kdm2a is required for mouse embryogenesis, its role in adult physiology has been largely unexplored. Using conditional deletion approaches, we demonstrate that Kdm2a deficiency leads to testicular atrophy and male infertility. Although spermatogonial stem cells remain unaffected, proliferating and differentiating spermatogonia exhibit delayed cell cycle progression and apoptosis. RNA-sequencing of purified spermatogonia and spermatocytes reveals Kdm2a-dependent repression of over 750 genes during spermatogonial differentiation. Chromatin immunoprecipitation followed by sequencing (ChIP-seq) demonstrates increased H3K36me2 levels at CpG-rich gene promoters …

An Alternative Neural Basis Underlying Leptin Resistance, Hongli Li, Cunjin Su, Yuanzhong Xu, Mette Q Ludwig, Jon Davis, Qingchun Tong

Faculty, Staff and Student Publications

Overconsumption of a palatable Western diet, a condition linked to central leptin resistance, contributes extensively to the current obesity epidemic. In this context, intensive efforts have focused on detailing the molecular mechanisms underlying leptin resistance. Here, we demonstrate that chronic inhibition of hypothalamic arcuate GABAergic neurons (ArcGABA) effectively reduced diet-induced obesity (DIO). Interestingly, palatable food exposure increased the activity level of ArcGABA neurons, which do not express the leptin receptor (non-LepR neurons; nonresponsive to leptin). Chronic activation of ArcGABA non-LepR neurons led to massive obesity, which was associated with normal leptin-induced pSTAT3 signaling but phenotypic leptin resistance; i.e., high leptin …

Efficacy Of A Novel Bcl-Xl Degrader, Dt2216, In Preclinical Models Of Jak2-Mutated Post-Mpn Aml, Zhe Wang, Anna Skwarska, Gowri Poigaialwar, Sovira Chaudhry, Alba Rodriguez-Meira, Pinpin Sui, Emmanuel Olivier, Yannan Jia, Varun Gupta, Warren Fiskus, Cassandra L Ramage, Guangrong Zheng, Alexandra Schurer, Kira Gritsman, Eirini P Papapetrou, Kapil Bhalla, Daohong Zhou, Adam J Mead, Raajit K Rampal, Jeffrey W Tyner, Hussein A Abbas, Naveen Pemmaraju, Qi Zhang Tatarata, Marina Konopleva

Faculty, Staff and Student Publications

Acute myeloid leukemia (AML) that evolves from myeloproliferative neoplasm (MPN) is known as post-MPN AML. Current treatments do not significantly extend survival beyond 12 months. B-cell lymphoma-extra large (BCL-xL) has been found to be overexpressed in leucocytes from patients with MPN, making it a potential therapeutic target. We investigated the role of BCL-xL in post-MPN AML and tested the efficacy of DT2216, a platelet-sparing BCL-xL proteolysis-targeting chimera, in preclinical models of post-MPN AML. We found that BCL2L1, the gene encoding BCL-xL, is expressed at higher levels in patients with post-MPN AML than in those with de novo AML. Single-cell multiomics …

Epha4 Signaling Dysregulation Links Abnormal Locomotion And The Development Of Idiopathic Scoliosis, Lianlei Wang, Xinyu Yang, Sen Zhao, Pengfei Zheng, Wen Wen, Kexin Xu, Xi Cheng, Qing Li, Anas M Khanshour, Yoshinao Koike, Junjun Liu, Xin Fan, Nao Otomo, Zefu Chen, Yaqi Li, Lulu Li, Haibo Xie, Panpan Zhu, Xiaoxin Li, Yuchen Niu, Shengru Wang, Sen Liu, Suomao Yuan, Chikashi Terao, Ziquan Li, Shaoke Chen, Xiuli Zhao, Pengfei Liu, Jennifer E Posey, Zhihong Wu, Guixing Qiu, Disco Study Group (Deciphering Disorders Involving Scoliosis & Comorbidities), Shiro Ikegawa, James R Lupski, Jonathan J Rios, Carol A Wise, Jianguo T Zhang, Chengtian Zhao, Nan Wu

Faculty, Staff and Students Publications

Idiopathic scoliosis (IS) is the most common form of spinal deformity with unclear pathogenesis. In this study, we first reanalyzed the loci associated with IS, drawing upon previous studies. Subsequently, we mapped these loci to candidate genes using either location-based or function-based strategies. To further substantiate our findings, we verified the enrichment of variants within these candidate genes across several large IS cohorts encompassing Chinese, East Asian, and European populations. Consequently, we identified variants in the EPHA4 gene as compelling candidates for IS. To confirm their pathogenicity, we generated zebrafish mutants of epha4a. Remarkably, the zebrafish epha4a mutants exhibited …

Synergistic Activity Of Combined Flt3-Itd And Mdm2 Inhibition With Quizartinib And Milademetan In Flt3-Itd Mutant/Tp53 Wild-Type Acute Myeloid Leukemias, Weiguo Zhang, Li Li, Muharrem Muftuoglu, Mahesh Basyal, Noriko Togashi, Koichi Iwanaga, Fumie Tanzawa, Masashi Numata, Dale L Bixby, Harry P Erba, Nikolai Podoltsev, Gary J Schiller, Prasanna Kumar, Arnaud Lesegretain, Takeshi Isoyama, Takahiko Seki, Naval Daver, Michael Andreeff

Faculty, Staff and Student Publications

Purpose: Acute myeloid leukemia (AML) is characterized by frequent mutations in FMS-like tyrosine kinase 3 (FLT3), overexpression of murine double minute 2 (MDM2), and TP53 wild-type (WT). Monotherapies targeting FLT3 frequently result in the development of resistant disease. In this study, we investigated the antileukemic efficacy of co-targeting FLT3 and MDM2 with quizartinib and milademetan (Q/M) in FLT3 internal tandem duplication (FLT3-ITD) AML cell lines, xenograft and patient-derived xenograft (PDX) models, and a phase I clinical trial.

Experimental design: Preclinical studies used human and murine cell lines carrying FLT3-ITD and/or tyrosine kinase domain mutations, TP53 WT/knockdown, leukemia cell xenograft models, …