Research Paper Volume 14, Issue 17 pp 6936—6956

Clinical significance for diagnosis and prognosis of POP1 and its potential role in breast cancer: a comprehensive analysis based on multiple databases

Xiao He1, *, , Ji Wang2, *, , Honghao Yu1, , Wenchang Lv1, , Yichen Wang1, , Qi Zhang1, , Zeming Liu1, , Yiping Wu1, ,

  • 1 Department of Plastic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
  • 2 Department of Emergency, The People’s Hospital of China Three Gorges University, The First People’s Hospital of Yichang, Yichang 443000, Hubei, China
* Equal contribution and co-first authors

Received: May 7, 2022       Accepted: August 17, 2022       Published: September 9, 2022
How to Cite

Copyright: © 2022 He et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Background: Breast cancer (BC) is one of the most common cancers in women. The discovery of available biomarkers is crucial for early diagnosis and improving prognosis. The effect of POP1 in BC remains unrevealed. Our study aims to explore the expression of POP1 in BC and demonstrate its clinical significance and potential molecular mechanisms.

Methods: The Cancer Genome Atlas (TCGA) BC cohort transcriptome data and corresponding clinical information were downloaded. GSE42568 cohort, GSE162228 cohort, GSE7904 cohort, and GSE161533 cohort in the Gene Expression Omnibus (GEO) database were used as verification groups. R software and several web tools were used for statistical analysis. Moreover, the proliferation, transwell, wound healing experiments, and flow cytometry were used for in vitro investigation.

Results: Compared with normal breast tissue, POP1 expression was up-regulated in BC tissue with a higher mutation rate. POP1 had good diagnostic value for BC and could be utilized as a new marker. POP1 was significantly correlated with multiple pathways in BC and played an important role in the immune infiltration of BC. High-POP1 expression patients were more prone to be responded to immunotherapy and had a significantly higher percentage of immunotherapy response rate. Moreover, POP1 promoted proliferation and migration and inhibited apoptosis in BC cells.

Conclusions: POP1 expression was up-regulated in BC and was associated with a poor prognosis. Patients with high-POP1 expression were more likely to be responded to immunotherapy. Our study can provide a potential marker POP1 for BC, which is beneficial in the diagnosis and treatment of BC.


BC: Breast cancer; TCGA: The Cancer Genome Atlas; GEO: Gene Expression Omnibus; ER: Estrogen receptor; TNBC: Triple-negative breast cancer; ROC: Receiver operating characteristic; AUC: Area under the curve; CI: Confidence interval; SMD: Standardized mean difference; SROC: Summary receiver operating characteristic; GO: Gene Ontology; GSEA: Gene set enrichment analysis; SiRNA: Small interference RNA; qRT-PCR: Real-time reverse transcription-PCR; OD: Optional density; DMEM: Dulbecco’s modified Eagle’s medium; FBS: Fetal bovine serum; PBS: Phosphate-buffered saline; Tregs: T cells regulatory; NK: Natural killer; DC: Dendritic cell; CCK-8: Cell Counting Kit-8; OS: Overall survival; CAR: Chimeric antigen receptor; ICB: Immune checkpoint blockade; PD-1: Programmed cell death protein-1; PD-L1: Programmed death ligand-1; CTLA-4: Cytotoxic T-lymphocyte-associated protein 4; TIDE: Tumor Immune Dysfunction and Exclusion; TIL: Tumor-infiltrating lymphocyte; TME: Tumor microenvironment; TIDE: Tumor Immune Dysfunction and Exclusion; MSI: Microsatellite instability.