Biology subjects

Macias, V.

Publications and source records attributed to Macias, V..

5 recordsLinked to original sources

bioRxiv2026

Integrative pipeline to profile and target endocrine therapy-insensitive cell populations in ER+ breast cancer

Up to 40% of patients with estrogen receptor positive breast cancer will experience relapse, either while on endocrine therapy (ET) or after ET is completed. A major contributor to ET failure is the presence of ET-insensitive cell populations within tumors. Here, we developed an analytical pipeline to systematically identify and target these populations by integrating single-cell RNA sequencing of ER+ tumors from the FELINE clinical trial with functional validation in a panel of patient-derived xenograft organoid models. We found that ET-insensitive cells are detected in all tumors regardless of clinical response and exhibit higher transcriptional heterogeneity than ET-sensitive populations. Using our pipeline, we identified and validated new therapeutic options that target patient-specific and shared ET-insensitive populations. Our integrated workflow provides a robust platform for identifying and targeting ET-insensitive cells and offers a translational framework to develop precision medicine approaches to improve outcome in breast cancer patients.

cancer biology↗

bioRxiv2024

IgG autoantibodies in bullous pemphigoid directly induce a pathogenic MyD88-dependent pro-inflammatory response in keratinocytes:

AbstractWhile autoantibodies in bullous pemphigoid (BP) are known to activate the innate immune response, their direct effect on keratinocytes, and the contribution of BP-IgG autoantibody-dependent keratinocyte responses to BP pathology is largely unknown. Herein, we performed multiplex immunoassays and bulk RNA-seq on primary keratinocytes treated with IgG from BP patients or controls. We identified a pro-inflammatory and proteolytic response with release of several cytokines (IL-6, IL-24, TGF-{beta}1), chemokines (CXCL16, CTACK, MIP-3{beta}, RANTES), C1s, DPP4, and MMP-9. We further validated this response using spatial transcriptomics and scRNA-seq of diseased and control skin. Blistering itself appeared to be major driver of this inflammatory response, with attached BP skin and spongiotic dermatitis revealing highly similar transcriptomes. Based on elevated levels of MyD88 and MyD88-dependent cytokines, we studied the impact of MyD88 deficiency in keratinocytes and demonstrated that MyD88 regulates BP-IgG-induced expression of IL-8, IL-24, and MMP-9. Induction of experimental BP in mice with Krt14-specific Myd88 knockout revealed significantly decreased disease severity with decreased serum levels of IL-1{beta}, IL-4, and IL-9 indicating the contributory role of keratinocyte-derived skin inflammation towards systemic response. Our work demonstrates the key contributions of keratinocyte and MyD88 dependent signaling in response to autoantibodies in BP. Key Messages-IgG antibodies from bullous pemphigoid (BP) patients induce significant upregulation of several inflammatory markers in keratinocytes including cytokines (IL-6, IL-24, TGF-{beta}1), chemokines (CXCL16, CTACK, MIP-3{beta}, RANTES), C1s, DPP4, and MMP9. Several of these markers, including IL-8, IL-24, and MMP9 are regulated by MyD88. -Spatial transcriptomics reveals that BP patient blistered skin demonstrated similar transcriptomic profiles to BP-IgG-treated keratinocytes. With attached skin demonstrating a comparable transcriptome to that seen in spongiotic dermatitis. -In a mouse BP model, keratinocyte-specific MyD88 deficiency results in decreased disease severity with a subsequent decrease in serum IL-1{beta}, IL-4, and IL-9 levels. Capsule summaryIgG from patients with bullous pemphigoid (BP) induces a pro-inflammatory response in keratinocytes, indicating their direct role in driving the inflammatory response in BP.

immunology↗

bioRxiv2024

Multiplex Imaging Reveals Novel Subcellular, Microenvironmental, and Racial Patterns of MRTFA/B Activation in Invasive Breast Cancers and Metastases

Breast cancer progression and metastasis involve the action of multiple transcription factors in tumors and in the cells of the tumor microenvironment (TME) and understanding how these transcription factors are coordinated can guide novel therapeutic strategies. Myocardin related transcription factors A and B (MRTFA/B) are two related transcription factors that redundantly control cancer cell invasion and metastasis in mouse models of breast cancer, but their roles in human cancer are incompletely understood. Here, we used a combination of multiplexed immunofluorescence and bioinformatics analyses to show that MRTFA/B are concurrently activated in tumor cells, but they show distinct patterns of expression across different histological subtypes and in the TME. Importantly, MRTFA expression was elevated in metastatic tumors of African American patients, who disproportionately die from breast cancer. Interestingly, in contrast to publicly available mRNA expression data, MRTFA was similarly expressed across estrogen receptor (ER) positive and negative breast tumors, while MRTFB expression was highest in ER+ breast tumors. Furthermore, MRTFA was specifically expressed in the perivascular antigen presenting cells (APCs) and its expression correlated with the expression of the immune checkpoint protein V-set immunoregulatory receptor (VSIR). These results provide unique insights into how MRTFA and MRTFB can promote metastasis in human cancer, into the racial disparities of their expression patterns, and their function within the complex breast cancer TME. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/573909v1_ufig1.gif" ALT="Figure 1"> View larger version (52K): org.highwire.dtl.DTLVardef@12037b3org.highwire.dtl.DTLVardef@28e2feorg.highwire.dtl.DTLVardef@4e95e1org.highwire.dtl.DTLVardef@152019b_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2023

Gene editing in the Chagas disease vector Rhodnius prolixus by Cas9-mediated ReMOT Control

Rhodnius prolixus is currently the model vector of choice for studying Chagas disease transmission, a debilitating disease caused by Trypanosoma cruzi parasites. Despite the broad use of double-stranded RNA interference for the knockdown of gene function in R. prolixus, transgenesis and gene editing protocols are still lacking. Here we tested Receptor-Mediated Ovary Transduction of Cargo (ReMOT Control) and direct parental injection of CRISPR (DIPA-CRISPR) for the maternal delivery of CRISPR/Cas9 elements to developing R. prolixus oocytes, and strategies for the identification of insertions/deletions (indels) in target loci of resulting gene-edited G0 nymphs. We demonstrate successful ReMOT Control-mediated gene editing of the eye color markers Rp-scarlet and Rp-white, and the cuticle color marker Rp-yellow, with highest effectiveness obtained using the ovary-targeting BtKV ligand. These results provide proof-of-concepts for generating somatic mutations in R. prolixus and potentially for generating germline edited lines in triatomines. Our studies also suggest that optimal strategies for recovery of mutations include performing multiple gRNA injections and the use of visible phenotypes such as those displayed in the Rp-scarlet, Rp-white and Rp-yellow loci for future Co-CRISPR experiments. These results will lay the foundation for gene editing protocols for triatomines and could lead to the development of novel control strategies for vectors of Chagas disease. Author SummaryRhodnius prolixus is an insect vector of the protozoan Trypanossoma cruzi, causative agent of debilitating Chagas disease. To fight the spread of the disease, it has been suggested that biological control of the insect should be attempted. Gene editing by the novel CRISPR methodology holds great promise in this sense, as it enables to target almost any gene in the genome for mutagenesis, thus allowing the control of insect physiology and reproduction. Here we have tested protocols for the delivery of CRISPR reagents as an attempt to enable genome editing of the vector. Our results show that maternal delivery of CRISPR by the ReMOT Control method is efficient for mutating eye and cuticle color genes in the resulting nymphs, generating edited animals with red eyes, white eyes or a yellow cuticle. This is the first report of gene editing in a vector of Chagas disease and should lay the basis to produce modified animals either unable to carry the T. cruzi parasite or to reproduce.

molecular biology↗

bioRxiv2021

Label-free imaging of collagen fibers in tissue slices using phase imaging with computational specificity

Evaluating the tissue collagen content in addition to the epithelial morphology has been proven to offer complementary information in histopathology, especially in oncology tumor staging and prediction of survival in cancer patients. One imaging modality widely used for this purpose is second harmonic generation microscopy (SHGM), which reports on the nonlinear susceptibility associated with the collagen fibers. Another method is polarization light microscopy (PLM) combined with picrosirius-red (PSR) tissue staining. However, SHGM requires expensive equipment and provides limited throughput, while PLM and PSR staining are not part of the routine surgical pathology workflow. Here, we utilize phase imaging with computational specificity (PICS) to computationally infer the collagen distribution of unlabeled tissue, with high specificity. PICS utilizes deep learning to translate quantitative phase images (QPI) into corresponding PSR images with high accuracy and inference speed of 200 milisecond per forwardpass through the model once trained. We developed a multimodal imaging instrument that yields both Spatial light Inference Microscopy (SLIM) and polarized light microscopy (PLM) images from the same field of view. Our results indicate that the distributions of collagen fiber orientation, length, and straightness reported by PICS closely match the ones from ground truth as defined by KL-divergence.

pathology↗