Elevated levels of RanBP7 mRNA in colorectal carcinoma are associated with increased proliferation and are similar to the transcription pattern of the proto-oncogene c-myc.
We have used suppression subtractive hybridisation, "in silico" cloning and reverse Northern dot blot analysis to identify significant up-regulation of RanBP7 transcription in a human colorectal carcinoma. Quantitative RT-PCR analyses using the Taqman system demonstrated that RanBP7 mRNA levels were elevated in 47/75 colorectal tumours. There was no significant difference in 17 matched normal and tumour pairs and reduced levels in 11. Since RanBP7 specifies a key member of nuclear transport receptors responsible for the nuclear import of histone H1 and ribosomal proteins, we investigated whether this up-regulation might be proliferation-associated. RanBP7 mRNA copy numbers were significantly correlated with those of proliferating cell nuclear antigen in both normal and cancer tissue. Interestingly, the transcription pattern of the proto-oncogene c-myc showed a similar correlation with PCNA mRNA. Our results highlight the need for the careful interpretation of quantitative data that compare mRNA levels in normal and cancer tissue.
Li
S R
SR
Academic Department of Surgery, St Bartholomew's and the Royal London School of Medicine and Dentistry, London, United Kingdom.
Gyselman
V G
VG
Dorudi
S
S
Bustin
S A
SA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D002277:Carcinoma / Q000378:metabolism*; D002455:Cell Division / Q000235:genetics; D003106:Colon / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000378:metabolism*; D015536:Down-Regulation; D005260:Female; D016259:Genes, myc / Q000235:genetics; D006801:Humans; D028884:Karyopherins; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000096:biosynthesis*; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D000090063:Proto-Oncogene Mas; D016271:Proto-Oncogene Proteins c-myc / Q000096:biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014158:Transcription, Genetic; D015854:Up-Regulation; D020931:ran GTP-Binding Protein / Q000096:biosynthesis*
C466996:IPO7 protein, human; D028884:Karyopherins; C000715470:MAS1 protein, human; D009687:Nuclear Proteins; D000090063:Proto-Oncogene Mas; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D020931:ran GTP-Binding Protein