NTRK1 and neoplasm: We observed that cells in inferred tumor cluster A exhibited high expression of NDUFA4L2 and COX4I2, while cells in inferred tumor cluster B expressed high levels of PNMT and RET (Figure 3D and E), suggesting the different gene expression between tumor cluster A and B. PNMT is known as an enzyme that catalyzes the conversion of norepinephrine to epinephrine and that RET is a member of the receptor tyrosine kinase family, while NDUFA4L2 and COX4I2 respectively function in the oxidative phosphorylation and glycolysis pathways (Drilon et al., 2018; Mahmoodi et al., 2020; Sinkler et al., 2017).