Overexpression of DOCK6 in oral squamous cell cancer promotes cellular migration and invasion and is associated with poor prognosis.

ABSTRACT

OBJECTIVE: We aimed to identify the role of DOCK6 in oral squamous cell cancer (OSCC) in this study. DESIGN: DOCK6 expression in OSCC was analyzed using TCGA and GEO datasets and was verified by quantitative real-time PCR, Western blotting, and immunohistochemistry. Statistical analyses were performed to evaluate the relationships between DOCK6 expression and the clinicopathological characteristics of OSCC patients. Wound healing and Transwell assays were performed to assess OSCC cell migration and invasion, respectively. STRING and GO analyses and gene set enrichment analysis were used to identify DOCK6-interacting proteins, their functions and their potential pathways. RESULTS: DOCK6 was significantly upregulated at both the mRNA and protein levels in OSCC tissues (all P < 0.05). DOCK6 levels were positively correlated with age (P < 0.05), lymph node metastasis status (P < 0.001), clinical stage (P < 0.001), differentiation (P < 0.05), and poor clinical outcome (P < 0.05) in OSCC patients. Furthermore, univariate and multivariate analyses revealed that high DOCK6 expression (P < 0.01) and clinical stage III-IV (P < 0.05) might serve as independent prognostic factors for OSCC patients. Functionally, DOCK6 silencing significantly suppressed OSCC cell migration and invasion (all P < 0.05). Ten proteins that interact with DOCK6, more than ten functions related to cancer, and more than six pathways related to DOCK6 in OSCC were identified via bioinformatic methods. CONCLUSION: DOCK6 is upregulated in OSCC, is associated with a poor prognosis in OSCC patients and increases OSCC cells migration and invasion. These findings suggest that DOCK6 may be a potential therapeutic target with prognostic implication in patients with OSCC.