title: Tetraspanin 7 (TSPAN7) expression is upregulated in multiple myeloma patients and inhibits myeloma tumour development in vivo.
abstract: BACKGROUND
  Increased expression of the tetraspanin TSPAN7 has been observed in a number of cancers; however, it is unclear how TSPAN7 plays a role in cancer progression.
  
  
  METHODS
  We investigated the expression of TSPAN7 in the haematological malignancy multiple myleoma (MM) and assessed the consequences of TSPAN7 expression in the adhesion, migration and growth of MM plasma cells (PC) in vitro and in bone marrow (BM) homing and tumour growth in vivo. Finally, we characterised the association of TSPAN7 with cell surface partner molecules in vitro.
  
  
  RESULTS
  TSPAN7 was found to be highly expressed at the RNA and protein level in CD138(+) MM PC from approximately 50% of MM patients. TSPAN7 overexpression in the murine myeloma cell line 5TGM1 significantly reduced tumour burden in 5TGM1/KaLwRij mice 4 weeks after intravenous adminstration of 5TGM1 cells. While TSPAN7 overexpression did not affect cell proliferation in vitro, TSPAN7 increased 5TGM1 cell adhesion to BM stromal cells and transendothelial migration. In addition, TSPAN7 was found to associate with the molecular chaperone calnexin on the cell surface.
  
  
  CONCLUSIONS
  These results suggest that elevated TSPAN7 may be associated with better outcomes for up to 50% of MM patients.
authors: Myeloma Research Laboratory, School of Medical Sciences, University of Adelaide, and South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5000, SA, Australia.
authors: Chee Man
authors: CM
authors: Cheong
authors: Myeloma Research Laboratory, School of Medical Sciences, University of Adelaide, and South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5000, SA, Australia; Department of Haematology, SA Pathology, Adelaide 5000, SA, Australia.
authors: Annie W S
authors: AW
authors: Chow
authors: Myeloma Research Laboratory, School of Medical Sciences, University of Adelaide, and South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5000, SA, Australia.
authors: Stephen
authors: S
authors: Fitter
authors: Myeloma Research Laboratory, School of Medical Sciences, University of Adelaide, and South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5000, SA, Australia; School of Medicine, University of Adelaide, Adelaide 5005, SA, Australia.
authors: Duncan R
authors: DR
authors: Hewett
authors: Myeloma Research Laboratory, School of Medical Sciences, University of Adelaide, and South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5000, SA, Australia; Department of Haematology, SA Pathology, Adelaide 5000, SA, Australia; School of Medicine, University of Adelaide, Adelaide 5005, SA, Australia.
authors: Sally K
authors: SK
authors: Martin
authors: Myeloma Research Laboratory, School of Medical Sciences, University of Adelaide, and South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5000, SA, Australia.
authors: Sharon A
authors: SA
authors: Williams
authors: Department of Haematology, SA Pathology, Adelaide 5000, SA, Australia.
authors: L Bik
authors: LB
authors: To
authors: Myeloma Research Laboratory, School of Medical Sciences, University of Adelaide, and South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5000, SA, Australia; Department of Haematology, SA Pathology, Adelaide 5000, SA, Australia; School of Medicine, University of Adelaide, Adelaide 5005, SA, Australia; Centre for Cancer Biology and Hanson Institute, SA Pathology, Adelaide 5000, SA, Australia; Centre for Personalised Cancer Medicine, University of Adelaide, Adelaide 5000SA, Australia.
authors: Andrew C W
authors: AC
authors: Zannettino
authors: Myeloma Research Laboratory, School of Medical Sciences, University of Adelaide, and South Australian Health and Medical Research Institute (SAHMRI), Adelaide 5000, SA, Australia; Department of Haematology, SA Pathology, Adelaide 5000, SA, Australia; School of Medicine, University of Adelaide, Adelaide 5005, SA, Australia. Electronic address: kate.vandyke@health.sa.gov.au.
authors: Kate
authors: K
authors: Vandyke
mesh_terms: D000818:Animals; D037281:Calnexin / Q000235:genetics / Q000378:metabolism; D002448:Cell Adhesion; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D018920:Coculture Techniques; D015870:Gene Expression; D006801:Humans; D008810:Mice, Inbred C57BL; D009101:Multiple Myeloma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D009368:Neoplasm Transplantation; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism; D016016:Proportional Hazards Models; D059470:Tetraspanins / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D009419:Nerve Tissue Proteins; C404405:TSPAN7 protein, human; D059470:Tetraspanins; D037281:Calnexin
keywords: Adhesion; Calnexin; Migration; Multiple myeloma; Tetraspanin 7