Thesis and Dissertation Announcements

Dissertation Proposal Defense

Identifying Novel Oncogenic Differentiation-blocking Genes from Human Druggable Receptome in Neuroblastoma Cells

Major Advisor: Liqin Du

Committee Members:

• Mar Huertas
• Peggy Biga
• Snezna Rogelj
• Tamer Saad Kaoud

Zoom: https://txstate.zoom.us/j/85862773868pwd=PylaPsOdiybiCdBwfQr0tqtnBHxAEN.1

Meeting ID: 858 6277 3868, Passcode: 961195

Abstract: Neuroblastoma is the most common extracranial solid tumor in children and a major cause of pediatric cancer related deaths. High-risk neuroblastoma is often characterized by poor differentiation, resistance to therapy, and unfavorable clinical outcomes. Differentiation therapy, such as retinoic acid treatment, has shown clinical benefit by promoting tumor cell maturation, but the molecular mechanisms that block differentiation remain poorly understood, limiting the development of more effective targeted therapies. This research project aims to identify key receptor proteins that act as molecular barriers to neuroblastoma cell differentiation and to determine whether pharmacological inhibition of these receptors can restore differentiation and suppress tumor growth. By focusing on receptor-driven signaling pathways within the human druggable receptome, the study seeks to uncover critical regulators that maintain neuroblastoma cells in an undifferentiated and proliferative state. The project integrates high-throughput functional screening with system-level network analysis to identify candidate receptor genes involved in neuronal differentiation and cell proliferation. These candidates are further explored through signaling pathway and interaction network analyses, along with microRNA-based regulatory studies, to reveal mechanisms underlying differentiation control in neuroblastoma. A key translational component of this research involves evaluating FDA-approved and clinically advanced small-molecule inhibitors targeting the identified receptors. By assessing both differentiation induction and cell viability, the study aims to prioritize compounds that promote differentiation at non-toxic concentrations. This drug repurposing strategy offers a rapid and cost-effective pathway to identify promising therapeutic candidates. Overall, this research has the potential to advance understanding of neuroblastoma biology and contribute to the development of safer, more effective differentiation-based therapies for children with high-risk neuroblastoma

Bio: Saika Anne is a PhD researcher in Aquatic Resources and Integrative Biology at Texas State University, USA. Her interdisciplinary background in agriculture, genetics, and biology has shaped her interest in understanding complex biological processes. Her research interests include molecular biology, environmental stress responses, and integrative biological systems. She aims to pursue a career in academia and foster interdisciplinary collaboration to address biological and environmental challenges.

Dissertation Proposal Defense

Spatio-temporal dynamics of tropical mammalian carnivores: functional traits, niche conservatism and human impacts

Major Advisor:  Dr. Iván Castro-Arellano

Committee Members:

• Dr. Leila Siciliano-Martina
• Dr. Michael Clay Green
• Dr. Juliana Bedoya-Durán
• Dr. José F. González-Maya

Zoom: https://txstate.zoom.us/j/85151169049pwd=eK2TaYbopMOGsAwyYdgM6gBBm35Bca.1

Meeting ID: 851 5116 9049; Passcode: 843133 

Abstract: The mechanisms structuring mammalian carnivore assemblages (order Carnivora) remain incompletely understood, limiting biodiversity conservation efforts. Resource utilization, constrained by biomechanical and physiological factors, is central to these dynamics and linked to niche dimensions such as microhabitat, diet, and time. Among these, time represents a critical axis that can be partitioned to reduce resource overlap and competition. Functional traits, including body size and dental morphology, influence energetic requirements, prey size limits, and degrees of carnivory specialization, thereby facilitating trophic niche differentiation. Coexistence is further promoted through variation in hunting strategies, activity patterns, and habitat use. Analytical tools such as the Rosario algorithm enhance assessments of temporal overlap, yet applications remain limited. Comparative evidence indicates that activity patterns differ between island and continental species, reflecting adaptive responses to distinct ecological pressures. Anthropogenic disturbances, including fragmentation, urbanization, and apex predator loss disrupt temporal partitioning, intensify competition, and destabilize communities. My dissertation addresses critical gaps in understanding how mammalian carnivores use time as a niche axis across continental and island ecosystems under natural and human-modified conditions. Specifically, it aims to: (1) test whether diel activity patterns exhibit temporal niche conservatism between islands and continents; (2) examine interactions between spatio-temporal overlap and functional traits such as body size and dentition; and (3) evaluate how habitat fragmentation reshapes temporal partitioning and coexistence strategies. Chapter 1 updates the Rosario algorithm for cyclical pattern analysis using R. Chapter 2 investigates spatio-temporal partitioning among carnivore species, the influence of functional traits on activity patterns, and the role of temporal niche conservatism across continental and island ecosystems. Chapter 3 evaluates the effects of habitat fragmentation on carnivore activity patterns in Colombia, comparing large-scale patterns (continent vs. island) with local-scale dynamics (forest remnants functioning as islands within a transformed matrix). By integrating ecological theory, functional morphology, landscape ecology, and advanced analytical tools, my research aims to elucidate mechanisms driving mammalian carnivore assemblages’ structure and providing insights for biodiversity conservation in increasingly human-modified landscapes.

Bio: Tatiana is a wildlife biologist from Colombia. Growing up in a charming small town in the middle of the Colombian Andean mountains has fueled her interest in wildlife studies. She holds a bachelor’s degree in biology from Universidad del Quindío (2016) and a master's degree from Universidad del Valle (2024). Her research focuses on the ecology, taxonomy and conservation of tropical mammals. After completing her degree, she wants to remain in academia and will encourage collaboration between NGOs, local communities, and universities in Colombia with the goal of developing targeted conservation strategies for tropical ecosystems.