HMGIC expression in human adult and fetal tissues and in uterine leiomyomata

The high-mobility-group (HMG) protein gene, HMGIC, is localized to chromoso me 12, band q15, a region often rearranged in benign mesenchymal tumors, in cluding uterine leiomyomata. Although some evidence suggests a role in regu lation of cell proliferation, the precise function of HMGIC in the developm ent or progression of these tumors remains unclear. We investigated HMGIC e xpression in 17 fetal tissues (adrenal, aorta, bone, brain, heart, intestin e, kidney, liver, lung, muscle, ovary, placenta, skin, spleen, stomach, tes tis, and uterus) and 10 adult tissues (aorta, brain, cerebellum, fat, kidne y, liver, lung, lymph node, myometrium, and spinal cord) by Northern blot a nd reverse transcriptase-polymerase chain reaction (RT-PCR) assays. Compari sons between HMGIC gene expression in tumor samples from 11 uterine leiomyo mata and 7 normal matched myometrium or in vitro cell cultures (chorionic v illi, placenta, myometrium, leiomyoma, and skin) were also performed. The g ene was expressed in all fetal tissues tested but only in adult lung and ki dney. HMGIC was also expressed in leiomyoma tumor samples containing t(12; 14) and in all in vitro cell cultures. The pattern of HMGIC expression sugg ests that this gene is important in rapidly proliferating human fetal tissu es. Restoration of expression in leiomyomata required dysregulation of HMGI C. Transcripts of HMGIC can also be detected after in vitro cell culture, s uggesting that HMGIC expression may be affected by factors present in cultu re media and serum. Genes Chromosomes Cancer 25:316-322, 1999. (C) 1999 Wil ey-Liss, Inc.