Table 2.

Main findings regarding the role of NNMT in HNT.

Tumor Type	Biological and Clinical Role of NNMT
OSCC	- Increase in cell proliferation, colony formation, and tumor volume; - Overexpression in tumor samples; - Association with tumor size, histological grading, and pathological staging; - Higher enzyme activity in N+ OSCC; - Higher salivary levels in OSCC patients.
AdCC	- Higher expression in N+ and M+ AdCC cell lines.
OT	- Overexpression in recurrent lesions.
OMM	- Overexpression in ulcerated OMM; - Association with worse DFS.
PTC	- Overexpression in PTC samples and cell lines; - Correlation between NNMT and HNF-1β overexpression.
NPC	- Association with worse DSS and MeFS.
LSCC	- Overexpression in cell lines; - Increase in cell proliferation.
ESCC	- Overexpression in tumor samples - Overexpression in N+ ESCC; - Increase in cells growth, proliferation, and migration; - Increase tumor cell viability.