Efficacy of laser capture microdissection plus RT-PCR technique in analyzing gene expression levels in human gastric cancer and colon cancer.
BACKGROUND
Thymidylate synthase, dihydropyrimidine dehydrogenase, thymidine phosphorylase, and orotate phosphoribosyltransferase gene expressions are reported to be valid predictive markers for 5-fluorouracil sensitivity to gastrointestinal cancer. For more reliable predictability, their expressions in cancer cells and stromal cells in the cancerous tissue (cancerous stroma) have been separately investigated using laser capture microdissection.


METHODS
Thymidylate synthase, dihydropyrimidine dehydrogenase, thymidine phosphorylase, and orotate phosphoribosyltransferase mRNA in cancer cells and cancerous stroma from samples of 47 gastric and 43 colon cancers were separately quantified by reverse transcription polymerase chain reaction after laser capture microdissection.


RESULTS
In both gastric and colon cancers, thymidylate synthase and orotate phosphoribosyltransferase mRNA expressions were higher (p < 0.0001, p <0.0001 respectively in gastric cancer and P = 0.0002, p < 0.0001 respectively in colon cancer) and dihydropyrimidine dehydrogenase mRNA expressions were lower in cancer cells than in cancerous stroma (P = 0.0136 in gastric cancer and p < 0.0001 in colon cancer). In contrast, thymidine phosphorylase mRNA was higher in cancer cells than in cancerous stroma in gastric cancer (p < 0.0001) and lower in cancer cells than in cancerous stroma in colon cancer (P = 0.0055).


CONCLUSIONS
By using this method, we could estimate gene expressions separately in cancer cells and stromal cells from colon and gastric cancers, in spite of the amount of stromal tissue. Our method is thought to be useful for accurately evaluating intratumoral gene expressions.
Makino
Hiroshi
H
Department of Translational Oncology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan. makino@po.kyoundo.jp
Uetake
Hiroyuki
H
Danenberg
Kathleen
K
Danenberg
Peter V
PV
Sugihara
Kenichi
K
D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000378:metabolism*; D017931:DNA Primers / Q000737:chemistry; D042943:Dihydrouracil Dehydrogenase (NADP) / Q000096:biosynthesis; D020869:Gene Expression Profiling / Q000379:methods*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007834:Lasers; D042282:Microdissection; D009962:Orotate Phosphoribosyltransferase / Q000096:biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D013274:Stomach Neoplasms / Q000378:metabolism*; D013939:Thymidine Phosphorylase / Q000096:biosynthesis; D013940:Thymidylate Synthase / Q000096:biosynthesis
D017931:DNA Primers; D012333:RNA, Messenger; D042943:Dihydrouracil Dehydrogenase (NADP); D013940:Thymidylate Synthase; D009962:Orotate Phosphoribosyltransferase; D013939:Thymidine Phosphorylase