The overexpression of certain membrane-bound receptors is a hallmark of cancer progression and it has been suggested to affect the organization, activation, recycling and down-regulation of receptor-ligand complexes in human cancer cells. Thus, comparing receptor trafficking pathways in normal vs. cancer cells requires the ability to image cells expressing dramatically different receptor expression levels. Here, we have presented a significant technical advance to the analysis and processing of images collected using intensity based Förster resonance energy transfer (FRET) confocal microscopy. An automated Image J macro was developed to select region of interests (ROI) based on intensity and statistical-based thresholds within cellular images with reduced FRET signal. Furthermore, SSMD (strictly standardized mean differences), a statistical signal-to-noise ratio (SNR) evaluation parameter, was used to validate the quality of FRET analysis, in particular of ROI database selection. The Image J ROI selection macro together with SSMD as an evaluation parameter of SNR levels, were used to investigate the endocytic recycling of Tfn-TFR complexes at nanometer range resolution in human normal vs. breast cancer cells expressing significantly different levels of endogenous TFR. Here, the FRET-based assay demonstrates that Tfn-TFR complexes in normal epithelial vs. breast cancer cells show a significantly different E% behavior during their endocytic recycling pathway. Since E% is a relative measure of distance, we propose that these changes in E% levels represent conformational changes in Tfn-TFR complexes during endocytic pathway. Thus, our results indicate that Tfn-TFR complexes undergo different conformational changes in normal vs. cancer cells, indicating that the organization of Tfn-TFR complexes at the nanometer range is significantly altered during the endocytic recycling pathway in cancer cells. In summary, improvements in the automated selection of FRET ROI datasets allowed us to detect significant changes in E% with potential biological significance in human normal vs. cancer cells.
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http://dx.doi.org/10.1016/j.ymeth.2013.08.017 | DOI Listing |
Anim Cells Syst (Seoul)
December 2024
Department of Oral Biochemistry, Dental and Life Science Institute, School of Dentistry, Pusan National University, Yangsan, Republic of Korea.
(), a periodontal pathogen, has been implicated in the impairment of anti-tumor responses in colorectal cancer (CRC). The tumor microenvironment in CRC involves tumor-associated macrophages (TAMs), which are pivotal in modulating tumor-associated immune responses. The polarization of TAMs towards an M2-like phenotype promotes CRC progression by suppressing the immune system.
View Article and Find Full Text PDFAnim Cells Syst (Seoul)
January 2025
Department of Biochemistry, College of Natural Sciences, Chungnam National University, Daejeon, Korea.
Interferon gamma (IFNγ) is well-known for its ability to stimulate immune cells in response to pathogen infections and cancer. To develop an effective cancer therapeutic vaccine, CT26 colon carcinoma cells were genetically modified to express IFNγ either as a secreted form (sIFNγ) or as a membrane-bound form. For the membrane-bound expression, IFNγ was fused with Fas (mbIFNγ/Fas), incorporating the extracellular cysteine-rich domains, transmembrane, and cytoplasmic domains of Fas.
View Article and Find Full Text PDFMol Clin Oncol
February 2025
Department of Biological Sciences, Tennessee State University, Nashville, TN 37209, USA.
Although peptide vaccines offer a novel venue for cancer immunotherapy, clinical success has been rather limited. Cell-penetrating peptides, due to their ability to translocate through the cell membrane, could be conjugated to the peptide vaccine to2 enhance therapeutic efficiency. The S4 transduction domain of the shaker-potassium channel was conjugated to mammaglobin-A (MamA) immunodominant epitope (MamA2.
View Article and Find Full Text PDFFront Immunol
December 2024
Department of Medical Oncology, The First Hospital of China Medical University, Shenyang, Liaoning, China.
Background: Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, with the worst prognosis among all subtypes. The impact of distinct cell subpopulations within the tumor microenvironment (TME) on TNBC patient prognosis has yet to be clarified.
Methods: Utilizing single-cell RNA sequencing (scRNA-seq) integrated with bulk RNA sequencing (bulk RNA-seq), we applied Cox regression models to compute hazard ratios, and cross-validated prognostic scoring using a GLMNET-based Cox model.
Front Immunol
December 2024
Molecular Immunology and Gene Therapy, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.
Generation of high avidity T cell receptors (TCRs) reactive to tumor-associated antigens (TAA) is impaired by tolerance mechanisms, which is an obstacle to effective T cell therapies for cancer treatment. NY-ESO-1, a human cancer-testis antigen, represents an attractive target for such therapies due to its broad expression in different cancer types and the restricted expression in normal tissues. Utilizing transgenic mice with a diverse human TCR repertoire, we isolated effective TCRs against NY-ESO-1 restricted to HLA-A*02:01.
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