Reversion of transformed phenotype in ovarian cancer cells by intracellular expression of anti folate receptor antibodies

M. Figini, R. Ferri, D. Mezzanzanica, M. Bagnoli, E. Luison, S. Miotti, S. Canevari

Research output: Contribution to journalArticlepeer-review


The α-folate receptor (FR) is selectively overexpressed in 90% of nonmucinous ovarian carcinomas, whereas no expression is detectable in normal ovarian surface epithelium (OSE). Indirect evidence suggests that FR expression is associated with tumor progression and affects cell proliferation. To evaluate better the role of FR, we developed an approach based on intracellular expression of single-chain (sc) antibodies (intrabody) to downmodulate membrane expression of FR in ovary cancer cells. IGROV-1 and SKOV3 ovarian carcinoma cell lines were transtected with an anti-FR intrabody. Transfectants and parental cells were tested for FR, integrins and anti-FR intrabody expression by fluorescence-activated cell sorting (FACS), reverse transcription and polymerase chain reaction (RT-PCR) and/or immunoblotting. Cell growth characteristics and adhesion properties were evaluated in liquid, semisolid and organotypic cultures. The anti-FR scFv inhibited FR expression from 60 to 99%. At physiological concentrations of folate, proliferation varied directly as a function of FR expression. FR downmodulation was accompanied by reduced colony-forming ability in soft agar, morphological change of the cells, significant enhanced adhesion to laminin or Matrigel, a two- to three-fold increase in α6β4 integrin expression, and a marked reduction in laminin production. In three-dimensional organotypic cultures, anti-FR intrabody-transfected IGROV1 cells grew as a single-ordered layer, reminiscent of normal OSE growth in vivo. In conclusion, the anti-FR intrabody reverses the transformed phenotype in ovary cancer cells and may provide an efficient means to inhibit selectively the growth of these cells.

Original languageEnglish
Pages (from-to)1018-1025
Number of pages8
JournalGene Therapy
Issue number12
Publication statusPublished - Jun 2003


  • Human α-folate receptor
  • Intrabody
  • Organotypic culture
  • Ovarian carcinoma
  • Phenotype reversion

ASJC Scopus subject areas

  • Genetics


Dive into the research topics of 'Reversion of transformed phenotype in ovarian cancer cells by intracellular expression of anti folate receptor antibodies'. Together they form a unique fingerprint.

Cite this