Immunotherapy leads to cancer eradication despite the tumor's immunosuppressive environment. Here, we used extended long-term in-vivo imaging and high-resolution spatial transcriptomics of endogenous melanoma in zebrafish, and multiplex imaging of human melanoma, to identify domains that facilitate immune response during immunotherapy. We identified crater-shaped pockets at the margins of zebrafish and human melanoma, rich with beta-2 microglobulin (B2M) and antigen recognition molecules.
View Article and Find Full Text PDFInternalization from the cell membrane and endosomal trafficking of receptor tyrosine kinases (RTKs) are important regulators of signaling in normal cells that can frequently be disrupted in cancer. The adrenal tumor pheochromocytoma (PCC) can be caused by activating mutations of the rearranged during transfection (RET) receptor tyrosine kinase, or inactivation of TMEM127, a transmembrane tumor suppressor implicated in trafficking of endosomal cargos. However, the role of aberrant receptor trafficking in PCC is not well understood.
View Article and Find Full Text PDFInternalization from the cell membrane and endosomal trafficking of receptor tyrosine kinases (RTK) are important regulators of signaling in normal cells that can frequently be disrupted in cancer. The adrenal tumour pheochromocytoma (PCC) can be caused by activating mutations of the RET receptor tyrosine kinase, or inactivation of TMEM127, a transmembrane tumour suppressor implicated in trafficking of endosomal cargos. However, the role of aberrant receptor trafficking in PCC is not well understood.
View Article and Find Full Text PDFStudies of post-mortem human tissue provide insight into pathological processes, but are inherently limited by practical considerations that limit the scale at which tissue can be examined, and the obvious issue that the tissue reflects only one time point in a continuous disease process. We approached this problem by adapting new tissue clearance techniques to an entire cortical area of human brain, which allows surveillance of hundreds of thousands of neurons throughout the depth of the entire cortical thickness. This approach allows detection of 'rare' events that may be difficult to detect in standard 5 micrometre-thick paraffin sections.
View Article and Find Full Text PDFDifficulty achieving complete, specific, and homogenous staining is a major bottleneck preventing the widespread use of tissue clearing techniques to image large volumes of human tissue. In this manuscript, we describe a procedure to rapidly design immunostaining protocols for antibody labeling of cleared brain tissue. We prepared libraries of 0.
View Article and Find Full Text PDFTissue clearing of gross anatomical samples was first described over a century ago and has only recently found widespread use in the field of microscopy. This renaissance has been driven by the application of modern knowledge of optical physics and chemical engineering to the development of robust and reproducible clearing techniques, the arrival of new microscopes that can image large samples at cellular resolution and computing infrastructure able to store and analyze large data volumes. Many biological relationships between structure and function require investigation in three dimensions and tissue clearing therefore has the potential to enable broad discoveries in the biological sciences.
View Article and Find Full Text PDFThe rapidly increasing use of digital technologies requires the rethinking of methods to store data. This work shows that digital data can be stored in mixtures of fluorescent dye molecules, which are deposited on a surface by inkjet printing, where an amide bond tethers the dye molecules to the surface. A microscope equipped with a multichannel fluorescence detector distinguishes individual dyes in the mixture.
View Article and Find Full Text PDFThe oncogenic transcription factor STAT3 is aberrantly activated in 70% of breast cancers, including nearly all triple-negative breast cancers (TNBCs). Because STAT3 is difficult to target directly, we considered whether metabolic changes driven by activated STAT3 could provide a therapeutic opportunity. We found that STAT3 prominently modulated several lipid classes, with most profound effects on N-acyl taurine and arachidonic acid, both of which are involved in plasma membrane remodeling.
View Article and Find Full Text PDFSpherical aberration (SA) occurs when light rays entering at different points of a spherical lens are not focused to the same point of the optical axis. SA that occurs inside the lens elements of a fluorescence microscope is well understood and corrected for. However, SA is also induced when light passes through an interface of refractive index (RI)-mismatched substances (i.
View Article and Find Full Text PDFLeasing instead of purchasing scientific instruments is an economic option for academic core facilities to stay technologically ahead and competitive with predictable, consistent costs.
View Article and Find Full Text PDFTissue clearing has become an important tool for the investigation of biological systems in three dimensions. However, many pioneering techniques were based on serendipitous discoveries. Next-generation clearing methods have been (re)designed with a better understanding of the chemistry and physics required to equalize the refractive index throughout a sample which prevents the random bending of light that clouds biological tissues.
View Article and Find Full Text PDFFluorescence-based biosensors have become essential tools for modern biology, allowing real-time monitoring of biological processes within living cells. Intracellular fluorescent pH probes comprise one of the most widely used families of biosensors in microscopy. One key application of pH probes has been to monitor the acidification of vesicles during endocytosis, an essential function that aids in cargo sorting and degradation.
View Article and Find Full Text PDFThe neuronal synapse is a primary building block of the nervous system to which alterations in structure or function can result in numerous pathologies. Studying its formation and elimination is the key to understanding how brains are wired during development, maintained throughout adulthood plasticity, and disrupted during disease. However, due to its diffraction-limited size, investigations of the synaptic junction at the structural level have primarily relied on labor-intensive electron microscopy or ultra-thin section array tomography.
View Article and Find Full Text PDFUnderstanding physical and chemical processes at an organismal scale is a fundamental goal in biology. While science is adept at explaining biological phenomena at both molecular and cellular levels, understanding how these processes translate to organismal functions remains a challenging problem. This issue is particularly significant for the nervous system where cell signaling and synaptic activities function in the context of broad neural networks.
View Article and Find Full Text PDFCell Biol Toxicol
February 2016
Biological specimens are intrinsically three dimensional; however, because of the obscuring effects of light scatter, imaging deep into a tissue volume is problematic. Although efforts to eliminate the scatter by "clearing" the tissue have been ongoing for over a century, there have been a large number of recent innovations. This Review introduces the physical basis for light scatter in tissue, describes the mechanisms underlying various clearing techniques, and discusses several of the major advances in light microscopy for imaging cleared tissue.
View Article and Find Full Text PDFCell surface biotinylation is a biochemical approach to covalently bind membrane-impermeable biotin to the extracellular domain of membrane proteins, such as receptor tyrosine kinases (RTKs). Subsequent to ligand incubation periods, activated biotinylated receptors may internalize from the cell surface into early endosomes and then travel through intracellular compartments to either recycle back to the membrane or degrade in lysosomes. The biotin-labeled proteins may be detected through affinity purification with streptavidin agarose resins.
View Article and Find Full Text PDFRET encodes a receptor tyrosine kinase that is essential for spermatogenesis, development of the sensory, sympathetic, parasympathetic, and enteric nervous systems and the kidneys, as well as for maintenance of adult midbrain dopaminergic neurons. RET is alternatively spliced to encode multiple isoforms that differ in their C-terminal amino acids. The RET9 and RET51 isoforms display unique levels of autophosphorylation and have differential interactions with adaptor proteins.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
November 2010
Internalization and intracellular trafficking of membrane proteins are now recognized as essential mechanisms that contribute to a number of cellular processes. Current methods lack the ability to specifically label the plasma membrane of a live cell, follow internalization of labeled membrane molecules, and conclusively differentiate newly formed membrane-derived vesicles from pre-existing endocytic or secretory structures in the cytoplasm. Here, we detail a visualization method for surface biotinylation of plasma membrane-derived vesicles that allows us to follow their progress from membrane to cytosol at specific time points.
View Article and Find Full Text PDFMutations to the RET proto-oncogene occur in as many as one in three cases of thyroid cancer and have been detected in both the medullary (MTC) and the papillary (PTC) forms of the disease. Of the nearly 400 chromosomal rearrangements resulting in oncogenic fusion proteins that have been identified to date, the rearrangements that give rise to RET fusion oncogenes in PTC remain the paradigm for chimeric oncoprotein involvement in solid tumors. RET-associated PTC tumors are phenotypically indolent and relatively less aggressive than RET-related MTCs.
View Article and Find Full Text PDFThe inherited cancer syndrome multiple endocrine neoplasia type 2 (MEN 2) is caused by mutations of the RET receptor tyrosine kinase and is characterized by medullary thyroid carcinoma. MEN 2 subtypes have distinct mutational spectrums and vary in severity. The most severe disease subtype, MEN 2B, is associated with a specific RET mutation (M918T) that has been predicted to alter downstream signaling and target gene expression patterns.
View Article and Find Full Text PDFThe RET receptor tyrosine kinase has essential roles in cell survival, differentiation, and proliferation. Oncogenic activation of RET causes the cancer syndrome multiple endocrine neoplasia type 2 (MEN 2) and is a frequent event in sporadic thyroid carcinomas. However, the molecular mechanisms underlying RET's potent transforming and mitogenic signals are still not clear.
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