title: H2 relaxin overexpression increases in vivo prostate xenograft tumor growth and angiogenesis.
abstract: Our study reports a preliminary investigation into the role of human H2 relaxin in prostate tumor growth. A luciferase-expressing human prostate cancer cell line, PC-3, was generated and termed PC3-Luc. PC3-Luc cells were transduced with lentiviral vectors engineering the expression of either enhanced green fluorescent protein (eGFP) or both H2 relaxin and eGFP in a bicistronic format. These transduced cells were termed PC3-Luc-eGFP and PC3-Luc-H2/eGFP, respectively. To gauge effects, PC3-Luc-H2/eGFP and PC3-Luc-eGFP cells were injected into NOD/SCID mice and monitored over 6 weeks. PC-3 tumor xenografts overexpressing H2 relaxin exhibited greater tumor volumes compared to control tumors. Circulating H2 relaxin levels in sera increased with the relative size of the tumor, with moderately elevated H2 relaxin levels in mice bearing PC3-Luc-H2/eGFP tumors compared to PC3-Luc-eGFP tumors. Zymographic analysis demonstrated that proMMP-9 enzyme activity was significantly downregulated in H2 relaxin-overexpressing tumors. An advanced angiogenic phenotype was observed in H2 relaxin-overexpressing tumors indicated by greater intratumoral vascularization by immunohistochemical staining of endothelial cells with anti-mouse CD31. Moreover, PC3-Luc-H2/eGFP tumors exhibited increased VEGF transcript by reverse-transcription PCR, compared to basal levels in control animals. Taken together, our study provides the first account of a potential role of H2 relaxin in prostate tumor development.
authors.affiliation: Division of Stem Cell and Differentiation, Ontario Cancer Institute, University Health Network, Toronto, Canada.
authors.forename: Josh D
authors.initials: JD
authors.lastname: Silvertown
authors.forename: Jonathan
authors.initials: J
authors.lastname: Ng
authors.forename: Takeya
authors.initials: T
authors.lastname: Sato
authors.forename: Alastair J
authors.initials: AJ
authors.lastname: Summerlee
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Medin
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D005819:Genetic Markers; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D016513:Mice, SCID; D009389:Neovascularization, Pathologic; D010641:Phenotype; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000473:pathology*; D012065:Relaxin / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014161:Transduction, Genetic; D014183:Transplantation, Heterologous; D014407:Tumor Cells, Cultured; D015854:Up-Regulation
chemical_list: D005819:Genetic Markers; C095068:RLN2 protein, human; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D012065:Relaxin