Panoply™ Human DKK1 Over-expressing Stable Cell Line

Perineural invasion (PNI) is associated with a poor prognosis in patients with head and neck squamous cell carcinoma (HNSCC), yet the underlying mechanisms remain unclear. Here, researchers found that Dickkopf-1 (DKK1), a secreted protein in the Wnt signaling pathway, is highly expressed in HNSCC cells and tissues. High DKK1 expression is statistically significantly correlated with T-stage, N-stage, PNI, and poor prognosis in HNSCC. DKK1 overexpression enhances the migratory capacity of cancer cells; furthermore, DKK1-overexpressing cancer cells promote invasion into peripheral nerves both in vitro and in vivo. Mechanistic studies indicate that DKK1 activates the PI3K-AKT signaling pathway. The enhanced migration of neuroblastoma cells induced by DKK1-overexpressing HNSCC cell lines can be reversed by the Akt inhibitor MK2206. The association between DKK1 and PNI was also confirmed in clinical HNSCC samples. A nomogram incorporating variables such as T-stage, N-stage, DKK1 expression, and PNI was constructed to predict 3-year and 5-year overall survival and disease-free survival rates. In summary, DKK1 induces neurite outgrowth and promotes PNI by activating the PI3K-AKT signaling pathway in tumor cells. MK2206 may serve as a potential therapeutic agent for HNSCC patients with PNI.

To investigate the role of DKK1 in the progression of head and neck squamous cell carcinoma (HNSCC), researchers generated stable DKK1-overexpressing cell lines using HNSCC cell lines such as FaDu and TU686, validating them via real-time quantitative PCR (Figure 1A), Western blot (Figure 1B), and ELISA (Figure 1C). Transwell assays demonstrated that DKK1 overexpression enhanced the migratory capacity of FaDu and TU686 cells (Figure 1D). Colony formation assays confirmed that DKK1 overexpression also promoted cell proliferation (Figure 1E). Subsequently, the researchers subcutaneously injected DKK1-overexpressing cells and control cells into nude mice. The results showed that tumors derived from DKK1-overexpressing cells were larger in volume (Figure 1F) and heavier (Figure 1G) than those derived from control cells. Tumor growth rates were accelerated in the DKK1-overexpression group (Figure 1H). Furthermore, immunohistochemistry (IHC) analysis revealed elevated DKK1 expression levels (Figure 1I) and an increased Ki67-positive rate (Figure 1J) in the DKK1-overexpressing subcutaneous xenograft tumors. Additional H&E staining and immunofluorescence (IF) assays revealed an interesting phenomenon: in the DKK1-overexpression group, the tumors invaded the subcutaneous peripheral nerves of the nude mice (Figure 1K). Collectively, these results indicate that DKK1 not only promotes the proliferation and migration of cancer cells but may also induce perineural invasion (PNI).

Figure 1. DKK1 promotes HNSCC cell migration in vitro and in vivo. (Wang J, et al., 2024)