title: BCG strain S4-Jena: An early BCG strain is capable to reduce the proliferation of bladder cancer cells by induction of apoptosis.
abstract: BACKGROUND
  Intravesical immunotherapy with Mycobacterium bovis bacillus Calmette-Guérin has been established as the most effective adjuvant treatment for high risk non-muscle-invasive bladder cancer (NMIBC). We investigated the differences between the S4-Jena BCG strain and commercially available BCG strains. We tested the genotypic varieties between S4-Jena and other BCG strains and analysed the effect of the BCG strains TICE and S4-Jena on two bladder cancer cell lines.
  
  
  RESULTS
  In contrast to commercially available BCG strains the S4-Jena strain shows genotypic differences. Spoligotyping verifies the S4-Jena strain as a BCG strain. Infection with viable S4-Jena or TICE decreased proliferation in the T24 cell line. Additionally, hallmarks of apoptosis were detectable. In contrast, Cal29 cells showed only a slightly decreased proliferation with TICE. Cal29 cells infected with S4-Jena, though, showed a significantly decreased proliferation in contrast to TICE. Concordantly with these results, infection with TICE had no effect on the morphology and hallmarks of apoptosis of Cal29 cells. However, S4-Jena strain led to clearly visible morphological changes and caspases 3/7 activation and PS flip.
  
  
  CONCLUSIONS
  S4-Jena strain has a direct influence on bladder cancer cell lines as shown by inhibition of cell proliferation and induction of apoptosis. The data implicate that the T24 cells are responder for S4-Jena and TICE BCG. However, the Cal29 cells are only responder for S4-Jena and they are non-responder for TICE BCG. S4-Jena strain may represent an effective therapeutic agent for NMIBC.
authors.affiliation: Institute of Medical Microbiology, Friedrich-Schiller-University, Jena, Germany. katja.schwarzer@med.uni-jena.de.
authors.forename: Katja
authors.initials: K
authors.lastname: Schwarzer
authors.forename: Martin
authors.initials: M
authors.lastname: Foerster
authors.forename: Thomas
authors.initials: T
authors.lastname: Steiner
authors.forename: Inge-Marie
authors.initials: IM
authors.lastname: Hermann
authors.forename: Eberhard
authors.initials: E
authors.lastname: Straube