LEP and neoplasm: In particular, during the carcinogenesis process, peritumoral AT progressively increases the expression of leptin, CD31, VEGF, VEGF-C, CD45, CD34, nucleostemin (NSTM), octamer-binding transcription factor 4 (OCT-4) and alpha-smooth muscle actin (α-SMA) under the stimulation of tumour-derived factors or AT-secreted adipokines such as leptin.