SPARC-like1 mRNA is overexpressed in human uterine leiomyoma

Uterine leiomyomas (ULs), also known as fibroids, are benign and monoclonal tumors frequently found in the female population. The genetic alterations that contribute to UL tumor development have not been well established, and the goal of this study was to reveal gene expression variation between ULs and healthy uterine tissue. We compared the gene expression profiles of 13 UL tumors with that of their adjacent normal tissue using the Differential Display mRNA assay (DDRT-PCR). Among the genes upregulated in some of the UL samples, several genes previously described in the context of cancer were identified, namely LIMK1, MCM3 and UHRF1. In addition, we identified a cDNA present in UL samples from distinct patients, which was absent from their normal tissue. Direct sequencing of this cDNA revealed a human SPARC-like1 (SPARCL1) mRNA homology. Through semi-quantitative PCR, we demonstrated that SPARCL1 was upregulated in approximately 77% of UL samples, but was absent in normal tissue. Real-time PCR (QPCR) revealed that SPARCL1 expression was increased 5-fold in ULs compared to adjacent normal tissue. These results suggest that the SPARCL1 gene is involved in UL development.