Sun Shin , Hyun Ho Kim , Jae Woong Kim , Doeun Rim , Changhyeok An , Yeun-Jun Chung , Sug Hyung Lee
{"title":"Cellular responses to neoadjuvant FOLFOX6-bevacizumab treatment in colorectal cancers analyzed by single-cell transcriptome analysis","authors":"Sun Shin , Hyun Ho Kim , Jae Woong Kim , Doeun Rim , Changhyeok An , Yeun-Jun Chung , Sug Hyung Lee","doi":"10.1016/j.prp.2024.155681","DOIUrl":null,"url":null,"abstract":"<div><div>Neoadjuvant chemotherapy combined with bevacizumab is used to treat colorectal cancer (CRC) patients by targeting tumor and vascular cells. However, it is known that other cells in the tumor microenvironment (TME) also change in response to this treatment. To investigate the changes in TME subpopulations in response to neoadjuvant FOLFOX6 plus bevacizumab, we studied pre- and post-treatment CRC tissues in four patients using single-cell RNA sequencing (scRNA-seq). This analysis classified nine cell types, including epithelial, vascular, immune cells, and fibroblasts. The cellular responses were widespread across the cell types, but there were specific subpopulations that altered, especially in vascular, immune, and fibroblast cells. In vascular subpopulations, CDH13-endothelial, arteriole, and CA4 capillary cells were selectively reduced. In immune cells, CD4+, CD8+ T cells, conventional dendritic cell type 1 (cDC1), and <em>CCL19</em>-expressing migrating DC (migDC-1) increased, while Th17, Th22, and tumor-associated macrophage (TAM) cells decreased, indicating that the treatment might be immunostimulatory. In fibroblasts, two major cancer-associated fibroblasts (matrix CAF (mCAF) and inflammatory CAF (iCAF)) increased, while conventional fibroblasts decreased, suggesting that the treatment remodeled the reparative/inflammatory processes, which might lead to reduced aggressiveness from the cancer-associated fibroblasts. In summary, our study reveals that neoadjuvant FOLFOX6 plus bevacizumab leads to alterations in particular subpopulations of vascular, immune, and reparative/inflammatory cells in the TME of CRCs. These alterations include vascular reduction, immunologic stimulation, and reduction of cancer-associated fibroblasts, which may underlie the responsiveness to the therapy in CRC. Our results may provide insights into the mechanisms of responsiveness/resistance to neoadjuvant FOLFOX6 plus bevacizumab therapy in CRCs.</div></div>","PeriodicalId":19916,"journal":{"name":"Pathology, research and practice","volume":null,"pages":null},"PeriodicalIF":2.9000,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Pathology, research and practice","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0344033824005922","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PATHOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Neoadjuvant chemotherapy combined with bevacizumab is used to treat colorectal cancer (CRC) patients by targeting tumor and vascular cells. However, it is known that other cells in the tumor microenvironment (TME) also change in response to this treatment. To investigate the changes in TME subpopulations in response to neoadjuvant FOLFOX6 plus bevacizumab, we studied pre- and post-treatment CRC tissues in four patients using single-cell RNA sequencing (scRNA-seq). This analysis classified nine cell types, including epithelial, vascular, immune cells, and fibroblasts. The cellular responses were widespread across the cell types, but there were specific subpopulations that altered, especially in vascular, immune, and fibroblast cells. In vascular subpopulations, CDH13-endothelial, arteriole, and CA4 capillary cells were selectively reduced. In immune cells, CD4+, CD8+ T cells, conventional dendritic cell type 1 (cDC1), and CCL19-expressing migrating DC (migDC-1) increased, while Th17, Th22, and tumor-associated macrophage (TAM) cells decreased, indicating that the treatment might be immunostimulatory. In fibroblasts, two major cancer-associated fibroblasts (matrix CAF (mCAF) and inflammatory CAF (iCAF)) increased, while conventional fibroblasts decreased, suggesting that the treatment remodeled the reparative/inflammatory processes, which might lead to reduced aggressiveness from the cancer-associated fibroblasts. In summary, our study reveals that neoadjuvant FOLFOX6 plus bevacizumab leads to alterations in particular subpopulations of vascular, immune, and reparative/inflammatory cells in the TME of CRCs. These alterations include vascular reduction, immunologic stimulation, and reduction of cancer-associated fibroblasts, which may underlie the responsiveness to the therapy in CRC. Our results may provide insights into the mechanisms of responsiveness/resistance to neoadjuvant FOLFOX6 plus bevacizumab therapy in CRCs.
期刊介绍:
Pathology, Research and Practice provides accessible coverage of the most recent developments across the entire field of pathology: Reviews focus on recent progress in pathology, while Comments look at interesting current problems and at hypotheses for future developments in pathology. Original Papers present novel findings on all aspects of general, anatomic and molecular pathology. Rapid Communications inform readers on preliminary findings that may be relevant for further studies and need to be communicated quickly. Teaching Cases look at new aspects or special diagnostic problems of diseases and at case reports relevant for the pathologist''s practice.