Expression of NGF family and their receptors in gastric carcinoma: a cDNA microarray study.
OBJECTIVE
To investigate the expression of NGF family and their receptors in gastric carcinoma and normal gastric mucosa, and to elucidate their effects on gastric carcinoma.


METHODS
RNA of gastric cancer tissues and normal gastric tissues was respectively isolated and mRNA was purified. Probes of both mRNA reverse transcription product cDNAs labeled with alpha-(33)P dATP were respectively hybridized with Atlas Array membrane where NGF and their family genes were spotted on. Hybridized signal images were scanned on phosphor screen with ImageQuant 5.1 software after hybridization. Normalized values on spots were analyzed with ArrayVersion 5.0 software. Differential expression of NGF family and their receptors mRNA was confirmed between hybridized Atlas Array membranes of gastric cancer tissues and normal gastric mucosa, then their effects on gastric carcinoma were investigated.


RESULTS
Hybridization signal images on Atlas Array membrane appeared in a lower level of nonspecific hybridization. Both of NGF family and their receptors Trk family mRNA were expressed in gastric cancer and normal gastric mucosa. But adversely up-regulated expression in other tissues and organs. NGF, BDGF, NT-3, NT-4/5, NT-6 and TrkA, B and C were down-regulated simultaneously in gastric carcinoma in comparison with normal gastric mucosa. Degrees of down-regulation in NGF family were greater than those in their receptors Trk family. Down-regulation of NT-3 and BDGF was the most significant, and TrkC down-regulation level was the lowest in receptors Trk family.


CONCLUSIONS
Down-regulated expression of NGF family and their receptors Trk family mRNA in gastric cancer is confirmed. NGF family and their receptors Trk family probably play a unique role in gastric cancer cell apoptosis by a novel Ras or Raf signal transduction pathway. Their synchronous effects are closely associated with occurrence and development of gastric carcinoma induced by reduction of signal transduction of programmed cell death.
Du
Jian-Jun
JJ
Department of General Surgery, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shanxi Province, China.
Dou
Ke-Feng
KF
Peng
Shu-You
SY
Qian
Bing-Zhi
BZ
Xiao
Hua-Sheng
HS
Liu
Feng
F
Wang
Wei-Zhong
WZ
Guan
Wen-Xian
WX
Gao
Zhi-Qing
ZQ
Liu
Ying-Bin
YB
Han
Ze-Guang
ZG
D002277:Carcinoma / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D009414:Nerve Growth Factors / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000032:analysis; D017475:Receptors, Nerve Growth Factor / Q000235:genetics*; D013274:Stomach Neoplasms / Q000235:genetics*
D009414:Nerve Growth Factors; D012333:RNA, Messenger; D017475:Receptors, Nerve Growth Factor