Correlation analyses between INHBA expression, immune infiltrates and miRNAs. A, Waterfall plot showing Spearman correlation between INHBA expression level and infiltrating ratios (IR) of different immune cells, as computed by immune cell deconvolution. Rho > 0.4 was considered relevant (dashed line). *, P ≤ 0.05; ***, P ≤ 0.001; ns, not significant. B, Correlation matrix between INHBA and the pro-tumor M1 signature showing Spearman rho and P-value symbols (*, P ≤ 0.05; **, P ≤ 0.01; ***, P ≤ 0.001) in the upper triangular matrix and scatter plots in the lower triangular matrix. TPM = transcripts per million. C, Waterfall plot showing Spearman correlation between INHBA expression level and miRNAs (TCGA cohort). miRNAs with Rho < −0.4 and P < 0.05 were considered relevant (dashed line). D, Venn diagram showing intersections between negatively correlating miRNAs from C and miRNAs predicted to interact with the 3′UTR of INHBA by miRDB and Targetscan resulting in three candidates of interest (hsa-mir-106a, hsa-mir-20b, hsa-mir-9-1/2/3). Their putative binding sites to the INHBA 3′UTR are highlighted. E–G, Kaplan–Meier plots with log-rank test for overall survival of patients with OPSCC (TCGA cohort) based on tumor miRNA expression of the outlined candidates (E: hsa-mir-106a, F: hsa-mir-20b, G: hsa-mir-9). Blue indicates low and red indicates high miRNA expression, as determined using median of raw counts as cutoff.
ARTICLE ABSTRACT
Patients with oropharyngeal squamous cell carcinoma (OPSCC) caused by human papilloma virus (HPV) exhibit a better prognosis than those with HPV-negative OPSCC. This study investigated the distinct molecular pathways that delineate HPV-negative from HPV-positive OPSCC to identify biologically relevant therapeutic targets. Bulk mRNA from 23 HPV-negative and 39 HPV-positive OPSCC tumors (n = 62) was sequenced to uncover the transcriptomic profiles. Differential expression followed by gene set enrichment analysis was performed to outline the top enriched biological process in the HPV-negative compared with HPV-positive entity. INHBA, the highest overexpressed gene in the HPV-negative tumor, was knocked down. Functional assays (migration, proliferation, cell death, stemness) were conducted to confirm the target's oncogenic role. Correlation analyses to reveal its impact on the tumor microenvironment were performed. We revealed that epithelial-to-mesenchymal transition (EMT) is the most enriched process in HPV-negative compared with HPV-positive OPSCC, with INHBA (inhibin beta A subunit) being the top upregulated gene. INHBA knockdown downregulated the expression of EMT transcription factors and attenuated migration, proliferation, stemness, and cell death resistance of OPSCC cells. We uncovered that INHBA associates with a pro-tumor microenvironment by negatively correlating with antitumor CD8+ T and B cells while positively correlating with pro-tumor M1 macrophages. We identified three miRNAs that are putatively involved in repressing INHBA expression. Our results indicate that the upregulation of INHBA is tumor-promoting. We propose INHBA as an attractive therapeutic target for the treatment of INHBA-enriched tumors in patients with HPV-negative OPSCC to ameliorate prognosis.
Patients with HPV-negative OPSCC have a poorer prognosis due to distinct molecular pathways. This study reveals significant transcriptomic differences between HPV-negative and HPV-positive OPSCC, identifying INHBA as a key upregulated gene in HPV-negative OPSCC's oncogenic pathways. INHBA is crucial in promoting EMT, cell proliferation, and an immunosuppressive tumor environment, suggesting its potential as a therapeutic target for HPV-negative OPSCC.
