The Hedgehog Signaling Networks in Lung Cancer: The Mechanisms and Roles in Tumor Progression and Implications for Cancer Therapy

Figure 1

Lung cancer. Lung cancer is mainly classified into small cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC). NSCLC is further classified into adenocarcinoma, squamous cell carcinoma, and large cell carcinoma. Adenocarcinoma is the most common lung cancer and arises in the distal airway. Squamous cell carcinoma and SCLC arise in the proximal airway. Large cell carcinoma also arises in the distal airway.