Although speaking Kansai-ben should be a breeze for Kitagawa, the problem is that she had left her hometown to work and stay in Tokyo since she was 17 so she had to go through training with a dialect teacher so as to get the intonation correct. As most of the cast members are from the Kansai region, Kitagawa commented that it is a very rare experience to be able to converse in Kansai-ben with her colleagues and staff.
The only cast member who does not come from the Kansai region is Hashimoto Manami who hails from Yamagata and she plays the lover of a movie producer (Hashizume Isao). Although Hashimoto has been named as the No.1 woman who men want to have as a lover, this is actually her first role as a lover. Hashimoto remarked that the biggest challenge for her is having to speak her lines in Kansai-ben so she has been practising hard to get the accent correct.
Sources: Sanspo 1 / Sanspo 2