IBEC PhD Discussions
by Enrico Almici and Albert Manzano
Investigating Pathological Extracellular Matrix Architecture
The composition and architecture of the extracellular matrix (ECM), and their dynamic alterations, play an important regulatory role on numerous cellular processes. Furthermore, structural and biochemical properties of the ECM are central in regulating cell behavior via mechanical, chemical and topological cues detected by receptors in the cell membrane which induce cytoskeleton rearrangement and/or cell nucleus gene expression. Indeed, distinct ECM architectures are encountered in the native stroma, which depend on tissue type, function and composition. For instance, ECM anisotropy and stiffness are associated with altered ECM degradation and remodeling in cancer. In turn, this architecture favors tumor progression and invasion. Moreover, numerous diseases are associated with mutations in genes encoding ECM components, leading to deficient mechanical properties and altered ECM structure. Thus, there is an increasing interest to exploit and consolidate this knowledge to improve patients’ treatment and care. In my work I focused on Collagen-VI related muscular dystrophies and Non-small cell lung cancer, to investigate in vitro and in patient tissues ECM-related biomarkers to be implemented in clinical setting. I employed automatic image segmentation to quantify fibrillar characteristics and investigate the association with the clinicopathological information from patients. Ultimately this analysis along with the tools presented is promising for addressing the need of novel descriptors, to stratify patients and evaluate their response to experimental treatments.
Enrico Almici, Nanobioengineering
Personalizing pediatric leukemia treatment using cell-based functional assays and microfluidics
Cancer personalized medicine improves treatment by testing different drugs in samples from every individual patient to select the best option in every case, maximizing efficacy and reducing side effects. Pediatric B-cell Precursor Acute Lymphoblastic Leukemia (BCP-ALL) has an acceptable cure rate, however, almost 10% of the cases are refractory to standard-of-care treatments, showing an urgent need for new therapeutic options. Here, we use Dynamic BH3 Profiling (DBP), a new assay that uses synthetic peptides mimicking the pro-apoptotic effect of the BH3 family of proteins, to predict treatment efficacy and anti-apoptotic adaptations conferring treatment resistance. Applying DBP in two BCP-ALL cell lines we identified new treatment options including both targeted agents and chemotherapies. We were also able to describe the mechanistic response of these cells after treatment, which acquired resistance using anti-apoptotic proteins that were later overcome using specific inhibitors called BH3 mimetics. Importantly, this resistance mechanism was also seen in patient-derived xenografts opening the use of these new combinations with BH3 mimetics in BCP-ALL patients. In the second part of the presentation, we developed a new version of the DBP protocol. Actual cytometry-based DBP requires a large number of viable cells which are easily obtained in liquid tumors but not in solid tumor biopsies, limiting the number of treatments that can be explored. To solve this problem, we developed a microfluidic-based DBP that drastically reduces cell requirement to perform the assay and helps to automatize the process to be implemented as a routinely clinical technique. We validated this microfluidic-based DBP using two gastrointestinal stromal tumor (GIST) cell lines obtaining similar results between the new protocol and the cytometry-based DBP. Finally, we used a primary GIST sample to identify a treatment combination that induced apoptosis to these patient cells, which proves that the microfluidic-based DBP can help to personalize solid cancers treatment.
Albert Manzano, Nanobioengineering
This PhD Discussion session will be held at Tower I, 11th floor Baobab room, there will be 30 avialable seats, the free spots will be assigned on a first come first served basis.