Evaluation of the correlation of vasculogenic mimicry, Notch4, DLL4, and KAI1/CD82 in the prediction of metastasis and prognosis in non-small cell lung cancer

Abstract

Vasculogenic mimicry (VM) is a new blood supply style in tumors and has long been treated as a useful factor in malignant tumor metastasis and prognosis. Notch4 (a marker of Notch signaling pathway receptors), DLL4 (a marker of Notch signaling pathway ligands) and KAI1/CD82 (a suppressor gene of tumor metastasis) are all effective predictive factors for tumor metastasis. In this study, we analyzed correlations among VM, Notch4, DLL4, and KAI1/CD82 in non-small cell lung cancer (NSCLC), and their respective associations with patients' clinicopathological parameters and survival rate in NSCLC.Positive rates of VM, Notch4, DLL4, and KAI1/CD82 in 189 whole NSCLC specimens were detected by histochemical and immunohistochemical staining. Moreover, patients' clinicopathological information was also collected.Positive rates of VM, Notch4, and DLL4 were significantly higher, and levels of KAI1/CD82 were significantly lower in NSCLC than in normal lung tissues. Positive rates of VM, Notch4, and DLL4 were positively associated with tumor size, lymph node metastasis (LNM), distant metastasis (DM) and tumor-node-metastasis (TNM) stage, and inversely with patients, overall survival (OS) time and positive rate of DLL4 were positively associated with tumor grade. Levels of KAI1/CD82 were negatively associated with tumor size, LNM, DM, and TNM stage. The KAI1/CD82+ subgroup had significantly longer OS time than did the KAI1/CD82- subgroup. In multivariate analysis, high VM, Notch4, DLL4 levels, tumor size, LNM, DM, TNM stage, and low KAI1/CD82 levels were potential to be independent prognostic factors for overall survival time (OST) in NSCLC patients.VM and the expression of Notch4, DLL4, and KAI1/CD82 represent promising markers for tumor metastasis and prognosis, and maybe potential therapeutic targets for NSCLC.

Figure 1

Positive staining of VM, or Notch4, or DLL4, or KAI1/CD82 in non-small cell lung cancer or the control tissue. (A) Positive staining of VM in the NSCLC tissue (100 magnification, red arrow is VM structure, black arrow is microvessel); (B) Positive staining of VM in the NSCLC tissue (400 magnification, red arrow is VM structure, black arrow is microvessel); (C) Positive staining of Notch4 in the cytoplasm of cancer cells (400 magnification); (D) Negative staining of Notch4 in the control tissue (100 magnification); (E) Positive staining of DLL4 in the cytoplasm of cancer cells (400 magnification); (F) Negative staining of DLL4 in the control tissue (400 magnification); (G) Negative staining of KAI1/CD82 in the NSCLC tissue (400 magnification); (H) Positive staining of KAI1/CD82 in the membrane and cytoplasm of the normal lung cells (400 magnification).

Figure 2

Kaplan–Meier analysis of the survival rate of patients with non-small cell lung cancer. The y-axis represents the percentage of patients; the x-axis, their survival in months. (A) Overall survival of all patients in relation to VM (log-rank = 126.642, P <.001); (B) Overall survival of all patients in relation to Notch4 expression (log-rank = 82.373, P <.001); (C) Overall survival of all patients in relation to DLL4 expression (log-rank = 62.322, P <.001); (D) Overall survival of all patients in relation to KAI1/CD82 expression (log-rank = 90.483, P <.001). In (A), (B), and (C) analyses, the green line represents patients with positive expression of VM, or Notch4, or DLL4 with a trend of worse survival time than the blue line representing the negative VM, or Notch4, or DLL4 group. In (D) analyses, the green line represents patients with positive expression of KAI1/CD82 with a trend of better survival time than the blue line representing the negative KAI1/CD82 group. (E) Overall survival of all patients in relation to the combination of KAI1/CD82, VM, Notch4, and DLL4 expression (log-rank = 177.119, P <.001). The blue line represents negative expression of KAI1/CD82 and positive expression of VM, Notch4, DLL4 and the green line represents positive expression of KAI1/CD82 and negative expression of VM, Notch4, DLL4. The red line represents other positive or negative expression of the proteins.