Differential expression of delta-like gene and protein in neuroblastoma, ganglioneuroblastoma and ganglioneuroma.
Neuroblastoma is an extremely malignant solid tumor in children, characterized by spontaneous differentiation and regression. An epidermal growth factor-like homeotic protein, delta-like (dlk), has been involved in differentiation of neuroblastoma cell lines, but is unknown in in vivo expression of neuroblastoma. By using in situ hybridization and immunohistochemistry, dlk mRNA and protein expression were studied in formalin-fixed archival tissues from 10 patients with neuroblastoma, five with ganglioneuroblastoma, and five with ganglioneuroma. Three adrenal tissues from children died of diseases other than adrenal tumors and one from an adult with pheochromocytoma were severed as normal and disease controls. The results showed strong immunoreactive dlk staining in endothelial cells in neuroblastoma, ganglioneuroblastoma and ganglioneuroma. Dlk was detectable in mature neuromatous stroma and gangliocytes of ganglioneuroma, but not in neuroblasts of neuroblastoma and ganglioneuroblastoma, neither in gangliocytes of ganglioneuroblastoma. In contrast, dlk mRNA expression was mainly observed in the gangliocytes, but was less intense in the neuroblasts and neuromatous stroma cells. Endothelial cells were essentially devoid of dlk mRNA expression. The findings indicated that there is differential expression of dlk gene and protein among neuroblastoma, ganglioneuroblastoma and ganglioneuroma. The stronger expression of dlk in gangliocytes in ganglioneuroma, in contrast to weaker or no expression in gangliocytes in ganglioneuroblastoma and neuroblasts in neuroblastoma, suggests upregulation of dlk during differentiation of neuroblastoma into more benign form. Furthermore, higher dlk protein expression in the tumor endothelium than in the endothelium of normal adrenal gland implies that dlk may regulate the endothelial function in neuroblastic tumors.
Hsiao
Chih-Cheng
CC
Department of Pediatrics, Division of Hematology/Oncology, Chang Gung Memorial Hospital, Kaohsiung, Taiwan.
Huang
Chao-Cheng
CC
Sheen
Jiunn-Ming
JM
Tai
Ming-Hong
MH
Chen
Ching-Mei
CM
Huang
Lynn L H
LL
Chuang
Jiin-Haur
JH
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004815:Epidermal Growth Factor / Q000235:genetics / Q000378:metabolism; D005260:Female; D018305:Ganglioneuroblastoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D005729:Ganglioneuroma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006023:Glycoproteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D018302:Neoplasms, Neuroepithelial / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D009447:Neuroblastoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
D006023:Glycoproteins; D012333:RNA, Messenger; D004815:Epidermal Growth Factor