Cells living in aggregates can perform more complex tasks than individual cells, but they also face key challenges as they have less access to space and nutrients. Tumors, like the healthy tissues they disrupt, must balance these physical forces and effectively distribute metabolites to continue to grow. Dr. Klumpe [Merck Fellow] will use yeast as a simplified model of cell aggregation to engineer diverse aggregates and observe their growth and maintenance over many generations. Understanding how certain properties of an aggregate affect its long-term stability can shed light on "design principles" that underlie the persistence of tumors, as well as what stabilizes other multicellular structures, such as healthy tissue and biomaterials. Dr. Klumpe received her PhD from the California Institute of Technology and her BS/BA from North Carolina State University.

Cancer cells rely on efficient uptake, conversion, and exchange of nutrients and vitamins to support their rapid growth and survival. The molecular transport channels that allow passage of nutrients between the different cellular compartments are critical for the survival of cancer cells and are thus promising as potential drug targets. However, drug discovery efforts are hampered by a lack of basic understanding of these channels' identities, functions, and regulation inside cancer cells. Dr. Kory's research aims to identify transporters central to cancer cell nutrient supply and detoxification pathways and determine their role in the emergence, survival, and aggressiveness of cancer. Her research is relevant to all cancers, but particularly pediatric, blood, and breast cancers.

Cancer initiation and progression stems from cell division errors that promote chromosome breakage and accumulation of mutations. Dr. Krishnamoorthy [HHMI Fellow] will use cutting-edge, cross-disciplinary approaches to provide insights into the fundamental question of how cell division shapes the cancer genome. Understanding the mechanisms of cancer genome complexity will help identify better diagnostics and treatments for cancers linked with high levels of genome alterations. Dr. Krishnamoorthy received her PhD from Vanderbilt University, Nashville and her MS from Middle Tennessee State University, Murfreesboro and her BS from PES Institute of Technology, Bangalore. 

Dr. Lalanne investigates the biophysical determinants of gene expression. Dysregulation of the expression of select oncogenes and tumor suppressors in specific tissues is sufficient to initiate tumorigenesis. Such dysregulation can arise from small-scale genetic changes that alter the binding sites of transcription factors in otherwise inactive enhancers (the short, non-coding regions of DNA to which transcription factors bind, activating gene expression). Despite substantial efforts in functional genomics, the quantitative connection between DNA sequence and expression remains largely elusive. Using a combination of single-cell transcriptomics and reporter assays, Dr. Lalanne plans to decipher the underlying sequence determinants of cell type-specific gene regulation. His goal is to formulate predictive models of which mutations in the non-coding genome can perturb the gene expression program and ultimately lead to cancer development.

In both embryonic development and disease, the same genetic mutation can lead to highly variable outcomes in different individuals. Dr. Lammers aims to shed light on the drivers of this nongenetic variability using the developing zebrafish embryo as a model system. By combining fluorescence microscopy and single-cell sequencing, he will test whether subtle differences in gene expression within individual cells can explain why some embryos with a given genetic mutation survive to adulthood, while others perish within the first 24 hours of their development. His findings will provide a quantitative foundation for understanding the genetic and molecular basis of cancer outcomes in human patients where, for instance, tumors with the same underlying mutations often exhibit dramatically different disease courses.

Dr. Lammers will train Variational Autoencoders to learn low-dimensional latent space representations of whole-embryo transcriptomes and grayscale images depicting embryonic morphology. He will then train a third neural network to translate from transcriptional latent space to morphological latent space. Together, these three networks will comprise a new computational method, morphSeq, that takes single-cell transcriptomes of mutant and wildtype embryos as input and produces predictions for corresponding embryo morphologies as its output.

Dr. Lapointe examines how the synthesis of proteins (translation) is controlled, as dysregulated translation is a ubiquitous feature of cancer. He is focused on a key challenge: how regulation that originates at the end of a messenger RNA (mRNA, a genetic molecule that encodes a protein) impacts the start of translation, which occurs near the beginning of the mRNA. His goal is to reveal and analyze dynamic pathways that underlie this fundamental mechanism to control gene expression. Using an integrated approach of single-molecule fluorescence microscopy, structural, and biochemical strategies, this research should yield generalizable insights into how translation is precisely regulated and how it is disrupted in a wide array of cancers.

Stable levels of ions (such as sodium or potassium) are critical for human health. Imbalanced ion concentrations indicate a metabolic disorder and are related to the process of metastasis. Dr. Liu aims to develop small molecule therapies that target proteins involved in metabolic disorders. To this end, she is developing computational methods to screen billions of compounds and identify potential drug candidates. With this project she hopes to not only meet an urgent therapeutic need but also improve the computational-based drug discovery pipeline.

Dr. Luo [HHMI Fellow] is focusing on the interplay between energy-producing mitochondria and the nucleus inside mammalian cells. Mitochondria contain their own small genome that encodes some proteins, but the vast majority are encoded in the cell's nucleus. The communication between mitochondria and the nucleus to produce the proteins necessary to properly function is tightly controlled, and its dysregulation has been implicated in human diseases including cancer. Dr. Luo is using ribosome profiling in parallel with CRISPR to quantitatively monitor translation (the process of protein production from RNA) on the mitochondrial surface and identify key regulators of this process. She hopes gaining an understanding of the underlying mechanism will yield fundamental insights into mitochondrial biology and its role in disease.

Metastatic cancers exploit cellular machinery to increase their proliferative potential and direct invasive cell migration. Specifically, cancer cells can adjust the translation of RNA into proteins to keep up with the demands of growth and metastasis. An important way that cells fine-tune their translation and quickly modulate cellular responses is through localized translation, or the translation of proteins in other areas of the cell further from the nucleus. To study the scope of localized translation, Dr. Luo has developed a highly sensitive, spatially-specific, and optically-controlled technique, which enables the quantification of translation at any given subcellular location. She will focus on understanding mechanisms of localized translation by identifying which genes are locally translated, how they are regulated, and why this process is important. Understanding the molecular mechanism of local protein synthesis could yield invaluable insights into the basis of cancer metastasis and inform therapeutic strategies. 

Patients with the same cancer diagnosis may experience very distinct disease progressions and treatment responses. These differences between patients have been associated with their degree of intra-tumor heterogeneity-the genetic, epigenetic, spatial, and environmental differences between the tumor cells. Characterizing the genetic and epigenetic states of different tumor cells is key to understanding how intra-tumor heterogeneity influences tumor progression, expansion, metastasis, and treatment response. Recent advances in single-cell RNA sequencing and spatial transcriptomics (which shows the spatial distribution of RNA molecules within a tissue sample) provide new opportunities to study intra-tumor heterogeneity in higher resolution. Dr. Ma's research aims to characterize intra-tumor heterogeneity in terms of specific genetic and epigenetic measures, and eventually develop 3D tumor models that capture this heterogeneity across multiple cancer types. Dr. Ma received her BS from Zhejiang University and her PhD in computational biology from Carnegie Mellon University.

The proposed computational methods will be based on previous methods developed in the group. Dr. Ma will develop a better method for identifying tumor clones for spatially resolved transcriptomics (SRT) data using both copy number and allele information using HMM and HMRF. She will adapt optimal transport frameworks and include biological networks as prior knowledge for integrating epigenetic data with SRT and between SRT slices to construct 3D spatial tumor multi-omics models.