ICAM-5 (telencephalin) gene expression in head and neck squamous carcinoma tumorigenesis and perineural invasion!
ICAM-5 (telencephalin) is an intercellular adhesion molecule reported to be expressed only in the somatodendritic membrane of telencephalic neurons. We recently identified high ICAM-5 expression in a cDNA array study of head and neck neoplasms with a propensity for perineural invasion. To determine the association of this gene in tumorigenesis and perineural invasion, we analyzed the expression and functional status of ICAM-5 mRNA transcripts in 30 different human cancer cell lines and 25 head and neck squamous carcinoma specimens by reverse-transcriptase polymerase chain reaction (cell lines and specimens) and in vitro functional assays (cell lines). ICAM-5 transcripts were detected in 28 (93%) of 30 cell lines derived from primary head and neck, colon, thyroid, cervical, pancreatic, skin, and adenoid cystic carcinomas. In cell lines, small interfering RNA blocked ICAM-5 expression and inhibited cell proliferation. Treatment with the phosphatidylinositol 3'-kinase (PBK) inhibitor LY294002 resulted in ICAM-5 down-regulation. In tissue specimens, none of the 25 histologically normal oral mucosal specimens had detectable ICAM-5 level, whereas 16 (64%) of the 25 matched primary squamous carcinomas showed expression. Carcinoma specimens high ICAM-5 expression had a high incidence of perineural invasion. Our study indicates that ICAM-5 may play a role in tumorigenesis and perineural invasion, most likely through the P13K/Akt-signaling pathway.
Department of Pathology, Unit 85, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030-4009, USA.
S I
SI
Maruya
J N
JN
Myers
R S
RS
Weber
D I
DI
Rosenthal
R
R
Lotan
A K
AK
El-Naggar
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D015815:Cell Adhesion Molecules; D002471:Cell Transformation, Neoplastic / Q000378:metabolism; D002867:Chromones / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006258:Head and Neck Neoplasms / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D009025:Morpholines / Q000494:pharmacology; D009062:Mouth Neoplasms / Q000378:metabolism / Q000473:pathology; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D000081082:Phosphoinositide-3 Kinase Inhibitors; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D014407:Tumor Cells, Cultured
D015815:Cell Adhesion Molecules; D002867:Chromones; D004791:Enzyme Inhibitors; C086747:ICAM5 protein, human; D008562:Membrane Glycoproteins; D009025:Morpholines; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D000081082:Phosphoinositide-3 Kinase Inhibitors; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D034741:RNA, Small Interfering; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one