Prognostic significance of PD-L1 expression on cell-surface vimentin-positive circulating tumor cells in gastric cancer patients.
胃癌患者细胞表面波形蛋白阳性循环肿瘤细胞 PD-L1 表达的预后意义。
- 作者列表："Liu M","Wang R","Sun X","Liu Y","Wang Z","Yan J","Kong X","Liang S","Liu Q","Zhao T","Ji X","Wang G","Wang F","Wang G","Chen L","Zhang Q","Lv W","Li H","Sun M
:Although circulating tumor cells (CTCs) have shown promise as potential biomarkers for diagnostic and prognostic assessment in gastric cancer (GC), determining the predictive and prognostic value of programmed death-ligand 1 (PD-L1)-positive CTCs in patients with GC is a challenge. Here, we identified that the expression of total vimentin protein was positively correlated with PD-L1 and inhibited CD8+ T cell activation in patients with GC according to bioinformatics analysis. Notably, co-expression of PD-L1 and cell-surface vimentin (CSV) was detected by immunofluorescence and IHC assay in locally advanced GC tumor specimens and metastatic lymph nodes. Likewise, CSV expression level was significantly decreased after transiently knocking down PD-L1 in GC cell lines. Based on our established CTC detection platform, CTCs were isolated from peripheral blood samples collected from 70 patients (38 resectable and 32 unresectable) with GC using magnetic positive selection and a CSV-specific monoclonal antibody, 84-1. CSV+ PD-L1+ CTCs were observed in 50 of 70 (71%) GC patient samples, ranging from 0 to 261 mL-1 . A higher number of CSV+ PD-L1+ CTCs were significantly associated with a short survival duration and poor therapeutic response. This study demonstrated that detection of PD-L1+ CTCs using a CSV-enrichment method has promising value as a clinically relevant prognostic marker for GC.
: 尽管循环肿瘤细胞 (CTCs) 已显示出有望作为胃癌 (GC) 诊断和预后评估的潜在生物标志物, 确定程序性死亡配体 1 (PD-L1) 阳性 CTCs 在 GC 患者中的预测和预后价值是一个挑战。在此，我们根据生物信息学分析确定 GC 患者总波形蛋白的表达与 PD-L1 呈正相关，并抑制 CD8 + T 细胞活化。值得注意的是，通过免疫荧光和 IHC 试验检测局部晚期 GC 肿瘤标本和转移淋巴结中 PD-L1 和细胞表面波形蛋白 (CSV) 的共表达。同样，在 GC 细胞系中，瞬时敲低 PD-L1 后，CSV 表达水平显著降低。基于我们建立的 CTC 检测平台，使用磁阳性选择和一种 CSV 特异性单克隆抗体，用 GC 从 70 例患者 (38 例可切除，32 例不可切除) 采集的外周血样本中分离 CTCs, 84-1.在 70 例 (71%) GC 患者样本中的 50 例中观察到 CSV + PD-L1 + CTCs，范围为 0-261 mL-1。较高的 CSV + PD-L1 + ctc 数量与较短的生存期和较差的治疗反应显著相关。本研究表明，使用 CSV 富集法检测 PD-L1 + CTCs 作为 GC 的临床相关预后标志物具有良好的价值。
METHODS::Diffuse gastric cancer (DGC) is a lethal malignancy lacking effective systemic therapy. Among the most provocative recent results in DGC has been that the alter of the cellular cytoskeleton and intercellular adhesion. CD2-associated protein (CD2AP) is one of the critical proteins regulating cytoskeleton assembly and intercellular adhesion. However, no study has investigated the expression and biological significance of CD2AP in gastric cancer (GC) to date. Therefore, the aim of our study was to explore if the expression of CD2AP is associated with any clinical features of GC and to elucidate the underlying mechanism. Immunohistochemistry of 620 patient tissue samples indicated that the expression of CD2AP is downregulated in DGC. Moreover, a low CD2AP level was indicative of poor patient prognosis. In vitro, forced expression of CD2AP caused a significant decrease in the migration and invasion of GC cells, whereas depletion of CD2AP had the opposite effect. Immunofluorescence analysis indicated that CD2AP promoted cellular adhesion and influenced cell cytoskeleton assembly via interaction with the F-actin capping protein CAPZA1. Overall, the upregulation of CD2AP could attenuate GC metastasis, suggesting CD2AP as a novel biomarker for the prognosis and treatment of patients with GC.
METHODS::Aim: To identify the methylated-differentially expressed genes (MDEGs) that may serve as diagnostic markers and therapeutic targets in Epstein-Barr virus-associated gastric cancer (EBVaGC) and to explore the methylation-based pathways for elucidating biological mechanisms of EBVaGC. Materials & methods: Gene expression and methylation profiles were downloaded from GEO database. MDEGs were identified by GEO2R. Pathway enrichment analyses were conducted based on DAVID database. Hub genes were identified by Cytoscape, which were further verified by The Cancer Genome Atlas database. Results: A total of 367 hypermethylated, lowly expressed genes were enriched in specific patterns of cell differentiation. 31 hypomethylated, highly expressed genes demonstrated enrichment in regulation of immune system process. After validation using The Cancer Genome Atlas database, seven genes were confirmed to be significantly different hub genes in EBVaGC. Conclusion: EBVaGC-specific MDEGs and pathways can be served as potential biomarkers for precise diagnosis and treatment of EBVaGC and provide novel insights into the mechanisms involved.
METHODS:Gastric adenocarcinoma, like other cancers, is a multifactorial genetic disease, andmetastasis of cancer cells is one of the main features of this illness. The expressionlevels of the CFL1 gene have been modulated in this pathway. Using small interferingRNA (siRNA) in the treatment of gastric cancer is considered a hopeful genetherapeutic approach. The present study reported the level of CFL1 genes betweentumor and margin and healthy tissue of gastric cancer. Also, the features of a cationicnanoparticle with a polymer coating containing polyacrylic acid and polyethylenei-mine that were used in the delivery of CFL1 siRNA, were shown. Then thecytotoxicity, cellular uptake, and gene silencing efficiency of this nanoparticle wereevaluated with CFL1siRNA. Method:In this study, the CFL1 gene expression was measured in 40 gastricadenocarcinoma, marginal and 15 healthy biopsy samples by a real‐time polymerasechain reaction. Physicochemical characteristics, apoptosis, and inhibition of migrationof the delivery of CFL1 siRNA by nanoparticle and lipofectamine were investigated ingastric cancer cells. Result:The CFL1 expression was remarkably increased in gastric cancer tissues incomparison with the marginal samples and normal tissues (p< .05) and the biomarkerindex for CFL1 was obtained as 0.94, then this gene can be probably used as abiomarker for gastric cancer. After treatment of the AGS cell line by CFL1 siRNA, theCFL1 expression level of mRNA and migration in AGS cells were remarkablysuppressed after transfection. Furthermore, the amount of apoptosis increased(p< .05). Conclusion:Our results demonstrated that CFL1 downregulation in AGS cells caninterdict cell migration. Finally, our outcomes propose that CFL1 can function as anoncogenic gene in gastric cancer and would be considered as a potential purpose ofgene therapy for gastric cancer treatment