The finding in these leiomyosarcomas of rearrangements of the same regions of chromosomes 12 and 14 that are involved in the tumor-specific t(12;14)(q14-15;q23-24) of uterine leiomyoma indicates that the same genes in 12q and 14q might be important in the pathogenesis of benign and malignant smooth muscle tumors.
The cytogenetic profiles of leiomyoma and lipoma are strikingly similar; both tumor types have nonrandom rearrangements of 12q13-15, t(12;14) in leiomyoma and t(3;12) in lipoma, as well as variant rearrangements of the same 12q segment.
The three previously identified cytogenetic subgroups were all represented in this series: del(7) (q21.2q31.2) was found in 11, trisomy 12 in five, and t(12;14)(q14-15;q23-24) in one leiomyoma.
The expression of mRNAs encoding EGF and the EGF receptor in myometrial and leiomyoma cultures suggest that EGF may be involved in the autocrine/paracrine regulation of human uterine leiomyomata and myometrial growth.
In this study we analysed by immunohistochemistry the expression of p53 protein in 14 malignant fibrous histocytomas (MFHs), 22 other types of sarcoma (eight leiomyosarcomas, four rhabdomyosarcomas, four liposarcomas, two fibrosarcomas, two chondrosarcomas, one malignant schwannoma, and one dermatofibrosarcoma protuberans), and 25 non-malignant mesenchymal lesions (eight dermatofibromas, four cases of nodular fasciitis, three leiomyomas, three fibromatoses, two epithelioid.leiomyomas, two neurofibromas, one schwannoma, one myositis ossificans, and one giant cell tumour of tendon sheath).
Corresponding to increased progesterone receptor gene expression, the proliferation-associated antigen Ki-67 was also significantly elevated in the leiomyoma tissue.
The data showed that in fibroids compared to myometrium, 1) the relative abundance of IGF-I mRNA was not different, but there was an increase in the relative abundance of IGF-II mRNA (P < 0.001); 2) IGFBP-1 mRNA was undetectable in fibroids and detectable in only 1 specimen of myometrium; 3) there was no difference in the relative abundance of IGFBP-2 mRNA, but there was an increase in the relative abundance of IGFBP-3 mRNA in myometrium (P < 0.05).
The data showed that in fibroids compared to myometrium, 1) the relative abundance of IGF-I mRNA was not different, but there was an increase in the relative abundance of IGF-II mRNA (P < 0.001); 2) IGFBP-1 mRNA was undetectable in fibroids and detectable in only 1 specimen of myometrium; 3) there was no difference in the relative abundance of IGFBP-2 mRNA, but there was an increase in the relative abundance of IGFBP-3 mRNA in myometrium (P < 0.05).
The objective of this study was to examine the possible steroid dependence of IGF, IGFBP and IGF receptor gene expression and IGFBP synthesis in uterine leiomyomata, using tissues from women cycling normally and made hypo-oestrogenic by a gonadtrophin-releasing hormone agonist (GnRHa).
Our data show that the mRNAs encoding IGF-I, IGF-II, IGFBP-2, and IGFBP-3 are expressed in both fibroids and myometrium and that fibroids express more IGF-II and less IGFBP-3 mRNA than myometrium.