# Analysis and validation of necroptosis-related diagnostic biomarkers associated with immune infiltration in bronchopulmonary dysplasia

## TL;DR

This study identifies a necroptosis-related gene, STAT4, as a potential diagnostic marker for bronchopulmonary dysplasia and explores its link to immune infiltration.

## Contribution

The study introduces a diagnostic nomogram based on necroptosis-related genes and evaluates their relationship with immune infiltration in BPD.

## Key findings

- 27 differentially expressed necroptosis-related genes were identified, including those involved in necroptosis and inflammatory response.
- Three hub genes (PELI1, PYGL, and STAT4) were selected, with STAT4 showing diagnostic potential (AUC > 0.7).
- Immune infiltration analysis revealed differences in six immune cell types between BPD and control groups.

## Abstract

Bronchopulmonary dysplasia (BPD) is the most common serious complication in very preterm infants. This study aims to identify necroptosis-related genes (NRGs) and analyze the relationship between necroptosis-related diagnostic markers and immune infiltration in BPD.

We obtained the dataset GSE32472 from the GEO database and analyzed the differentially expressed NRGs (DE-NRGs). We identified the biological functions and pathways of DE-NRGs. RF (random forest) and LASSO (least absolute shrinkage and selection operator) algorithms were applied to identify hub genes. We explored the immune landscape of BPD and controls by CIBERSORT. The correlations between hub genes and immune cells were evaluated using Spearman correlation analysis. ELISA was used to verify the diagnostic value of hub genes in patients with BPD in our hospital.

27 DE-NRGs were screened. We found the primary biological functions and pathways of DE-NRGs, including necroptosis, and regulation of inflammatory response. Three hub genes (PELI1, PYGL, and STAT4) were identified and utilized to construct a diagnostic nomogram. The AUC value of the nomogram was greater than 0.7 in the validation dataset GSE188944. CIBERSORT showed that the proportions of 6 different immune cell types in the BPD group were higher or lower than the control group (P < 0.05). Correlation analysis showed that three hub genes may correlate with immune cells to varying degrees. Serum ELISA results of PELI1 and PYGL showed no significant difference between BPD and Controls (P > 0.05), the expression level of STAT4 was downregulated in BPD samples (P < 0.05), and the AUC value of the STAT4 was higher than 0.7.

The necroptosis-related gene STAT4 can be a diagnostic marker of BPD patients. The necroptosis-related gene and immune infiltration may be related to the progression of BPD.