Table 1 The signature of 25 genes for characterizing lung cancer subtypes. Enrichment shows that there are 23 unique genes in the signature.

ABCC3

ATP-binding cassette, sub-family C (CFTR/MRP), member 3

ABC transporters

BICD2

bicaudal D homolog 2 (Drosophila)

CDA

cytidine deaminase

Pyrimidine metabolism, Drug metabolism

CLDN3

claudin 3

Cell adhesion molecules, Tight junction, Leukocyte transendothelial migration

DPP4

dipeptidyl-peptidase 4

HGD

homogentisate 1,2-dioxygenase (homogentisate oxidase)

Tyrosine metabolism, Styrene degradation

ITPKA

inositol 1,4,5-trisphosphate 3-kinase A

Inositol phosphate metabolism, Calcium signaling pathway, Phosphatidylinositol signaling system

KRT14

keratin 14 (epidermolysis bullosa simplex, Dowling-Meara, Koebner)

Cell communication

KRT6A, KRT6B, KRT6C

keratin 6A, keratin 6B, keratin 6C,

Cell communication

MUC3B

mucin 3B, cell surface associated

MUC5B

mucin 5B, oligomeric mucus/gel-forming

NMNAT2

nicotinamide nucleotide adenylyltransferase 2

Nicotinate and nicotinamide metabolism

NTRK2

neurotrophic tyrosine kinase, receptor, type 2

MAPK signaling pathway

RHCG

Rh family, C glycoprotein

SERPINB13

serpin peptidase inhibitor, clade B (ovalbumin), member 13

SOX2

SRY (sex determining region Y)-box 2

SPINK1

serine peptidase inhibitor, Kazal type 1

SPRR1A

small proline-rich protein 1A

TJP3

tight junction protein 3 (zona occludens 3)

Tight junction

TOX3

TOX high mobility group box family member 3

VSNL1

visinin-like 1