Subcutaneous transplant tumour tissues (H128-Mut, control), BPM tumour tissues, and LM tumour tissues were subjected to IHC analysis, which showed that H128-LM and H128-BPM still have the expression of neuroendocrine markers, including CD56, CHGA, SYP and INSM1 (Fig. 3C-G, P > 0.05). The gene discussed is SYP; the disease is neoplasm.