Overexpression of SUGT1 in human colorectal cancer and its clinicopathological significance

As recent technological innovations make it possible to clarify the concordant relationship between genomic alterations and aberrant gene expression during the progression of colorectal cancer (CRC), we aimed at identifying new overexpressing genes with genomic amplification on the responsible loci in CRC. The candidate gene was found using cDNA microarray and array-based comparative genomic hybridization (CGH) analysis after laser microdissection (LMD) in 132 Japanese CRC. We focused on SUGT1, which is associated with the assembling of kinetochore proteins at the metaphase of the cell cycle, with significant association between genetic alterations and expression. SUGT1 mRNA expression was evaluated in 98 CRC cases to determine the clinicopathological significance of SUGT1 expression. The mean level of SUGT1 mRNA expression in tumor tissue specimens was significantly higher than in non-tumor tissue. The high SUGT1 expression group was characterized by a significantly elevated frequency of recurrence and a significantly poorer prognosis than the low expression group. There was a significant association between poor prognosis of CRC cases and the overexpression of SUGT1 with genomic amplification of the loci concordantly. The amplification of SUGT1 might give rise to promote the transcription of the gene directly subsequent to the progression of CRC cases with worsening prognosis.