Increased expression of DNAJC7 promotes the progression of hepatocellular carcinoma by influencing the cell cycle and immune microenvironment

Abstract

Background: Hepatocellular carcinoma (HCC) is the leading cause of cancer-related mortality worldwide owing to the lack of effective and early diagnostic tools and therapeutic approaches. DNAJC7, a member of the DnaJ heat shock family, is crucial in protein folding and stability; however, its specific functions and mechanisms in HCC remain unclear.

Objective: This study aimed to explore the role of DNAJC7 in HCC progression and evaluate its potential clinical significance as a prognostic marker.

Methods: Public databases (TCGA, ICGC, GEO, and TIMER) were used to assess DNAJC7 expression, correlations with clinical parameters, and related signaling pathways. Proliferation, migration, invasion, and cell cycle assays were performed to evaluate the function of DNAJC7 in HCC. Immune infiltration and associations with checkpoint proteins were analyzed using TIMER, and a Gene Set Enrichment Analysis (GSEA) was used to explore enriched pathways.

Results: DNAJC7 expression was higher in HCC tissues than in adjacent normal tissues and was associated with advanced malignancy and poor prognosis, including a lower overall survival, progression-free survival, and disease-free survival. DNAJC7 knockdown resulted in reduced malignant behavior of HCC cells, leading to S-phase cell cycle arrest. Increased DNAJC7 expression was associated with immune cell infiltration and the presence of immunological checkpoint molecules, including CTLA4 and PD-1. GSEA highlighted the activation of key pathways, including WNT signaling and cell cycle regulation.

Conclusion: DNAJC7 regulates tumor cell proliferation, migration, invasion, and immune evasion by acting as an oncogene in HCC. It can serve as a diagnostic and prognostic biomarker and potential treatment target for HCC.

Keywords: DNAJC7; Hepatocellular carcinoma; Prognosis; Signaling pathway.

Fig. 1

Comparison of expression levels of DNAJC7 in tumors and normal tissues. (A) The mRNA expression levels of DNAJC7 in various tumors from the TIMER database. (B) The Protein expression levels of DNAJC7 in different tumor types from the CPTAC database. (C) Based on TCGA RNA-seq analysis, the expression level of DNAJC7 is significantly higher in tumor tissues compared to normal tissues. (D) Paired analysis further confirmed that the expression level of DNAJC7 in tumor tissues is significantly higher than that in normal tissues in the TCGA RNA-seq database. (E-H) Based on the RNA-seq data analysis from ICGC and GEO (GSE25097, GSE54238, and GSE36376), the expression level of DNAJC7 in tumor tissues is significantly higher than that in normal tissues

Fig. 2

High expression of DNAJC7 leads to malignant clinical characteristics and poor prognosis in HCC patients. (A-C) Based on TCGA RNA-seq analysis, the high expression of DNAJC7 is significantly associated with T stage, tumor stage, and histological grade in HCC patients. (D-F) The analysis results after data integration indicate that high expression of DNAJC7 leads to more advanced malignant clinical characteristics in HCC patients. (G-I) K-M survival analysis suggests that high expression of DNAJC7 leads to poorer survival in HCC patients. (J-K) The ROC curve indicates that DNAJC7 has significant prognostic diagnostic value in HCC patients

Fig. 3

In vitro experiments indicate that high expression of DNAJC7 promotes the proliferation of HCC cells. (A, B) In vitro assays using SK-HEP-1 and MHCC97H cells with DNAJC7-targeting siRNAs established a knockdown model, selecting the siRNA with the highest efficiency for further experiments. (C, D) CCK-8 assays showed that DNAJC7 knockdown significantly inhibited HCC cell growth. (E, F) Colony formation assays confirmed that DNAJC7 promotes cell proliferation

Fig. 4

In vitro experiments have shown that high expression of DNAJC7 promotes the invasion and migration ability of HCC cells. (A) Transwell assays showed that silencing DNAJC7 significantly reduced the invasive capacity of the cells. (B, C) Similarly, scratch assays revealed a marked decrease in their migratory ability

Fig. 5

Flow cytometry analysis shows that high expression of DNAJC7 affects cell cycle distribution by regulating DNA replication. (A) In the SK-HEP-1 cell line, the percentage of cells in the S phase is significantly reduced when DNAJC7 expression is decreased. (B) In the HCC97H cell line, the percentage of cells in the S phase is also significantly reduced when DNAJC7 expression is decreased

Fig. 6

Co-Expression and GSEA Enrichment Analysis of DNAJC7. A summary table lists the top five genes with the strongest synergistic or antagonistic expression relationships with DNAJC7. (B) Visualization of the top five genes showing synergistic or antagonistic expression patterns with DNAJC7. GSEA enrichment analysis results based on TCGA RNA-seq. (C) Cell Cycle; (D) Homologous Recombination; (E) WNT Signaling Pathway. GSEA enrichment analysis results based on ICGC RNA-seq. (F) Cell Cycle; (G) Homologous Recombination; (H) DNA Replication

Fig. 7

The regulatory role of DNAJC7 in the immune microenvironment. (A) The expression level of DNAJC7 shows a positive correlation with the infiltration levels of six types of immune cells: B cells, CD8 + T cells, CD4 + T cells, macrophages, neutrophils, and dendritic cells. (B-G) Spearman analysis reveals that the expression level of DNAJC7 is positively correlated with the expression of M1 macrophage marker (IRF5), neutrophil marker (ITGAM), and dendritic cell markers (NRP1, HLA-DPB1, ITGAX, and HLA-DRA)

Fig. 8

Spearman analysis indicates that the expression level of DNAJC7 is positively correlated with the expression of five immune checkpoints. (A) PDCD1; (B) CTLA4; (C) HAVCR2; (D) IDO1; (E) CD276