# Exploring the Role of PCDHGB4 in the Occurrence of Lung Squamous Cell Carcinoma Based on Bioinformatics Analysis

## TL;DR

This study uses bioinformatics to explore how PCDHGB4 affects lung squamous cell carcinoma development and patient outcomes.

## Contribution

The novel contribution is identifying PCDHGB4 as a potential prognostic marker and immunotherapy target in LUSC.

## Key findings

- PCDHGB4 is underexpressed in LUSC tissues compared to normal tissues.
- Higher PCDHGB4 expression correlates with worse patient survival in LUSC.
- PCDHGB4 is linked to immune cell infiltration and cancer-related pathways.

## Abstract

肺鳞状细胞癌（lung squamous cell carcinoma, LUSC）是非小细胞肺癌（non-small cell lung cancer, NSCLC）的亚型之一。有报道原钙黏蛋白γ家族的成员能通过抑制Wnt信号通路来调节肿瘤细胞的生长，原钙黏蛋白γB4（protocadherin-gamma subfamily B4, PCDHGB4）作为家族成员在LUSC中的研究少有报道，本研究旨在通过生物信息学方法探究PCDHGB4在LUSC发生发展中的作用及潜在的预后价值。

应用癌症基因组图谱（The Cancer Genome Atlas, TCGA）、cBioPortal和UALCAN等数据库，对PCDHGB4在LUSC中的表达与预后、临床病理特征、免疫细胞浸润、免疫调节基因、免疫检查点抑制剂（immune checkpoint inhibitors, ICIs）和甲基转移酶等进行分析。单细胞水平的研究对细胞亚型的聚类结果和PCDHGB4在不同免疫细胞亚群中的表达情况进行了分析。此外，我们还比较了LUSC组织与正常组织中PCDHGB4的启动子甲基化水平，并对其进行了蛋白质-蛋白质相互作用和突变分析。最后基于差异表达基因进行富集分析。

生信分析结果显示PCDHGB4在LUSC组织的表达水平低于正常组织。生存分析显示，PCDHGB4表达增加与患者较差的预后有关。单细胞分析显示，PCDHGB4主要在T细胞、单核细胞或巨噬细胞以及树突状细胞中表达，进一步发现PCDHGB4在肿瘤免疫中发挥着不可忽视的作用，并证实了PCDHGB4与免疫检查点途径基因、免疫调节基因和甲基转移酶有一定的相关性。此外，通过富集分析发现PCDHGB4参与了癌症相关的多条通路。

PCDHGB4在LUSC中低表达，PCDHGB4与患者预后不良有关，并且PCDHGB4与肿瘤免疫细胞浸润和通路密切相关。PCDHGB4可能是LUSC潜在的预后标志物和免疫治疗新靶点。

Clinicopathological features of LUSC patients with low and high expression of PCDHGB4

The significant prognostic values of CpG in PCDHGB4

Univariate and multivariate analysis of OS in patients with LUSC