DLK1 and AIDS dementia complex: DLK1 was found to be significantly up-regulated in 126 (72.4%) SCC specimens and 137 (77.4%) ADC specimens, whereas the expression was hardly detected in adjacent non-cancerous bronchial epithelium (48/156; 30.8%) or alveolus (7/181; 3.9%) (Figure 1 and Table 1).