In 1989 - 1995, she portrayed the Queen of the Night in a production of Mozart's Die Zauberflöte at the Shinjuku Cultural Center. She is known for Violetta in La traviata conducted by, Lauretta, Gretel, Juliette, In addition, she performed a multitude of operettas for many concerts. In 1990, Shinada crossed over from Japan to Italy for further operatic studies. She performed in music festivals and was regarded as one of Japan's finest vocalists. In 1994, she went with the Japanese Performance Association to a French music competition and won first prize. That year she performed in the Toho Gakuen School of Music's 30th anniversary ceremony as one of the top students. Shinada also performed in the Coca-Cola Special Musical Opera. She has worked on the music and script for Akai Kutsu and the operatic adaptation of the Yokohamafairy taleAoi Hitomi. All of her works have been performed in multiple opera circuits in Asia. Also, she has been noted for working with Yuki Kajiura on the anime series Noir, , and the OVA.hack//Liminality, in which she sang four versions of the song "liminality". A few of Kasahara's lines from "liminality" also make a cameo with Emily Bindiger on a remix of the .hack//SIGN song "The World". She is a frequent guest vocalist with See-Saw. She makes an appearance on Kajiura's solo albumFiction, singing a redone version of "Salva Nos" and a new song "Red Rose". In 2006, Shinada sang for the soundtrack My-Otome on the song "Materialise". In 2002, Shinada recorded a two-disc album entitled An Encounter featuring several of her most famous non-anime related performances, rerecorded with the Tokyo Konsei. She is featured as a vocalist for the Madlax soundtrack. In 2003 she sang the role of Forest bird in Siegfried conducted by . In 2013 she established Labravoce, a music school that combines music training with psychological counseling. On 12 May 2015 she appeared in the opera Humanitarian Cherry Blossoms, which premiered at the Russian Drama Theatre of Lithuania in Vilnius. It was composed by Yuki Ando to a libretto by Shinada. She sang the leading role of Yukiko. She sang the role again when the opera was performed in March 2017 at Shinjuku Cultural Center. She recorded television commercials using over 150 songs as of July 2016.