Expression of Terminally Glycosylated Calcitonin Receptor–Like Receptor in Uterine Leiomyoma: Endothelial Phenotype and Association with Microvascular Density

Abstract

Purpose: The role for the hypoxia-inducible angiogenic factor adrenomedullin (AM) in tumor growth and progression has been suggested. Calcitonin receptor^like receptor (CL) is a G protein^coupled receptor (GPCR) that mediates effects of AM, but little information is available on its expression and functional state in human tumors.The present study attempted to determine CL potential for antiangiogenic therapy of uterine leiomyoma. Experimental Design and Results: GPCR CL is transported to the cell surface and recognized byAM only when terminally/mature glycosylated.The presence and localization of this form of the receptor in tumor and surrounding myometrial tissues obtained from leiomyoma-bearing uteri were examined using deglycosylation, immunoblotting, and immunofluorescence analysis. The mature CL glycoprotein was expressed in both tissues and localized exclusively in normal and tumor endothelium within leiomyoma-bearing uteri. The functionality of the receptor expressed in myometrial microvascular endothelial cells (MMVEC) was examined in vitro using receptor internalization and angiogenic assays. The mature CL glycoprotein expressed by primary MMVECs was functional because AM interacted with this GPCR and induced its internalization as well as angiogenic effects (proliferation and migration) in MMVECs in vitro. Finally, the levels of tissue-expressed mature CL glycoprotein as a functional form of this GPCR were analyzed by immunoblotting. The expression of this functional form of the receptor in vivo was significantly decreased (P = 0.01) in leiomyoma tissue, and this was concurrent with the decrease in microvascular density (measured by Chalkley counting) in tumor compared with surrounding myometrium (P = 0.031). Conclusions: Our findings suggest that GPCR CL mediates angiogenic effects of AM in myometrium and that further evaluation of the properties of the CL expressed in both normal and tumor endothelium in vivo may be essential before targeting this endothelial GPCR for antiangiogenic therapies.

The Expression and Regulation of Adrenomedullin in the Human Endometrium: A Candidate for Endometrial Repair

“…Our finding that CLR protein is localized to endothelial cells of blood vessels in the human endometrium is consistent with previous studies (30, 37, 38). In addition, we have demonstrated CLR localization in the lymphatic vasculature.…”

An Integrative Genomic and Transcriptomic Analysis Reveals Potential Targets Associated with Cell Proliferation in Uterine Leiomyomas

“…Furthermore, we also verified new genomic imbalances mapping to 1q41, 2q32.1, 2q32.2, 2q35, 5q31.2, 5q35.3, 8p12, 8q24.3, 10p15.3, 10q21.3, 11q13.2, 12p11.21, 12p13.31, 16p11.2, 16q24.3, 17q21.31, 20p11.2 and 20p13. Among the 75 modulators, only CALCRL , COL3A1 , and FGFR1 were previously described to be associated with ULs [30], [31], [32], [33]. All 75 modulators were associated with ULs pathogenesis regardless of tumour multiplicity and menstrual cycle phase, which indicates that they play central roles in the aetiology of these tumours.…”

Adrenomedullin Haploinsufficiency Predisposes to Secondary Lymphedema

“…Paraffin-embedded or frozen sections of mouse skin and human tissues were prepared as previously described (Shimosawa et al , 2002; Nikitenko et al , 2006a, 2006b) and stained either with hematoxylin and eosin or Azan or processed for immunostaining. Histopathological analysis was performed by scoring epidermal thickening in the skin.…”