The patient, a White, Caucasian female, age 43, blood type A+, had been treated with radiation, steroids, cytoxan and 5-fluorouracil.

The AU565 cell line amplifies and overexpresses the HER-2/neu oncogene; it expresses the HER-3, HER-4 and p53 oncogenes.

Treating the cells with mycophenolic acid (MPA), phorbol 12-myristate 13-acetate (PMA), retinoic acid (RA) or the TA-1 monoclonal antibody to the extracellular domain of the HER-2/neu protein can induce cell differentiation.

Treatment of AU565 cells with Neu differentiation factor (NDF) also induces mature phenotype, which is characterized by the morphological appearance of the cells.

A culture submitted to the ATCC in April of 1995 was found to be contaminated with mycoplasma and progeny were cured by a 21-day treatment with BM Cycline.

The cells were assayed for mycoplasma, by the Hoechst stain, PCR and the standard culture test, after a six-week period following treatment. All tests were negative.

1. Remove and discard culture medium.
2. Briefly rinse the cell layer with 0.25% (w/v) Trypsin-0.53 mMxa0EDTA solution to remove all traces of serum that contains trypsin inhibitor.
3. Add 2.0 to 3.0 mL of Trypsin-EDTA solution to flask and observe cells under an inverted microscope until cell layer is dispersed (usually within 5 to 15 minutes).
   Note: To avoid clumping do not agitate the cells by hitting or shaking the flask while waiting for the cells to detach. Cells that are difficult to detach may be placed at 37°C to facilitate dispersal.
4. Add 6.0 to 8.0 mL of complete growth medium and aspirate cells by gently pipetting.
5. Add appropriate aliquots of the cell suspension to new culture vessels.
6. Incubate cultures at 37°C

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