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Biology subjects

Lubanska, D.

Publications and source records attributed to Lubanska, D..

3 recordsLinked to original sources

Profiling Glioma Stem Cell Dynamics via 3D-based Cell Cycle Reporter Assays

Successful containment of unwanted cell cycle progression in tumours such as glioblastoma (GBM) requires targeted therapeutic approaches which rely on understanding cell cycle dynamics in response to microenvironmental stimuli. Glioma Stem Cells (GSCs) can drive tumour initiation, recurrence, therapy resistance, and are often attributed to the heterogeneity and plasticity of GBM. In vitro models using patient-derived GSCs provide a life relevant tool for exploration of complex molecular mechanisms underlying the aggressive characteristics of GBM. Introduction of 3D tissue culture systems permits the study of spatial complexity of the tumour mass and enables control over diverse conditions within the surrounding microenvironment. This chapter demonstrates detailed methods to study spatio-temporal changes to the cell cycle dynamics using available fluorescent cell cycle reporter systems in combination with bioinformatics-based signal intensity and localization analysis. We present a successful approach that investigates the 3D cell cycle dynamics of GSC populations. This approach utilizes GBM neurosphere and organoid cultures, which are assessed over time and under therapeutic pressure. These models can be further explored, manipulated, and customized to serve specific experimental designs.

cancer biology↗

Atypical Cell Cycle Regulation over Neural Stem Cell Expansion

Populations of adult neural stem cells (NSCs) that reside in the mammalian brain aid in neurogenesis throughout life and can be identified by a type VI intermediate filament protein, Nestin. Cell cycle regulation plays an important role in maintaining a balance between self-renewal and differentiation and determining the fate of NSCs. Data from our group and others support that the atypical cyclin-like protein Spy1 (also called RingoA; gene SPDYA) plays a critical role in activating NSCs from a quiescent state. Elevated levels of Spy1 are found in aggressive human brain cancers, including glioblastoma. Using a conditional mouse model, we demonstrate that driving the expression of Spy1, in the Nestin-enriched NSC population of the brain, increases stemness characteristics, decreases differentiation, and increases susceptibility to oncogenic transformation. This study contributes to better understanding of intricate cell cycle mechanisms which lead to deviation from the homeostatic state, promoting aberrant changes in adult NSCs.

molecular biology↗

Tuberin levels during cellular differentiation in brain development

Tuberin is a member of a large protein complex, Tuberous Sclerosis Complex, and acts as a sensor for nutrient status regulating protein synthesis and cell cycle progression. Mutations in the Tuberin gene, TSC2, lead to the formation of tumors and developmental defects in many organ systems, including the central nervous system. Tuberin is expressed in the brain throughout development and levels of Tuberin have been found to decrease during neuronal differentiation in cell lines in vitro. Our current work investigates the levels of Tuberin at two stages of embryonic development in vivo, and we study the mRNA and protein levels during a time course using immortalized cell lines in vitro. Our results show that Tuberin levels remain stable in the olfactory bulb but decrease in the Purkinje cell layer during embryonic mouse brain development. We show here that Tuberin levels are higher when cells are cultured as neurospheres, and knockdown of Tuberin results in a reduction in the number of neurospheres. These data provide support for the hypothesis that Tuberin is an important regulator of stemness and the reduction of Tuberin levels might support functional differentiation in the central nervous system. Understanding how Tuberin expression is regulated throughout neural development is essential to fully comprehend the role of this protein in several developmental and neural pathologies. HIGHLIGHTSO_LITuberin protein levels are decreased in the Purkinje cell layer in later stages of embryonic development. C_LIO_LITuberin protein and mRNA levels decrease as cells undergo neuronal differentiation. C_LIO_LIDownregulation of Tuberin impairs neurosphere formation. C_LIO_LITuberin is implicated in the maintenance of stemness in the developing brain. C_LI

developmental biology↗