Summary: | <p>Abstract</p> <p>Background</p> <p>The three far-upstream element (FUSE) binding proteins (FBP1, FBP2, and FBP3) belong to an ancient family of single-stranded DNA binding proteins which are required for proper regulation of the <it>c-myc </it>proto-oncogene. Whereas it is known that <it>c-myc </it>alterations play a completely different role in various carcinomas of the urogenital tract, the relevance of FBPs is unclear.</p> <p>Methods</p> <p>FBP1, FBP3 and <it>c-myc </it>expression was studied in 105 renal cell, 95 prostate and 112 urinary bladder carcinomas by immunohistochemistry using tissue microarrays.</p> <p>Results</p> <p>High rates of FBP1 and FBP3 expression were observed in all cancer types. There was a concomitant up-regulation of FBP1 and FBP3 in renal cell and prostate carcinomas (p < 0.001 both). <it>C-myc </it>expression was detectable in 21% of prostate, 30% of renal and 34% of urothelial carcinomas. Interestingly, strong FBP1 and FBP3 expression was associated with <it>c-myc </it>up-regulation in clear cell renal cell carcinomas (p < 0.001 and 0.09 resp.), but not in bladder or prostate cancer.</p> <p>Conclusion</p> <p>The correlation between FBP1/FBP3, <it>c-myc </it>and high proliferation rate in renal cell carcinoma provides strong <it>in viv</it>o support for the suggested role of FBP1 and FBP3 as activators of <it>c-myc</it>. The frequent up-regulation of FBP1 and FBP3 in urothelial and prostate carcinoma suggests that FBPs also have an important function in gene regulation of these tumors.</p>
|