Definition of overexpressed in English:
overexpressed
adjective ˌəʊv(ə)rɪkˈsprɛstˌəʊv(ə)rɛkˈsprɛst
1Expressed in an excessive or exaggerated way.
2Genetics. Of a gene product: produced in abnormally large amounts.
Origin
1950s; earliest use found in Norman Mailer (1923–2007), novelist and journalist. From overexpress + -ed.