Antangana was sentenced in an overnight trial to 15 years in prison in 1997. He underwent trial a second time in Yaounde last year, again was found guilty and was sentenced to an additional 20 prison terms with a fine of $2.2 million to be paid to the Cameroon government, Radio France Internationale reported.
Antangana, who in 1994 was sent to Cameroon by his French employer, Jean Lefebre, was accused of embezzling funds from the state of Cameroon and stood trial without a lawyer, the radio station reported.
Antangana's family, lawyer and political commentators said both his trials were purely political, that he was targeted because at the time he was close with a politician who opposed President Paul Biya for the presidency, the radio station reported.
The French government didn't provide support for Antangana during the first 12 years of his imprisonment. That changed only when a new French ambassador came to Cameroon in 2009 and French officials began visiting him and attending his court hearings, the radio station reported.
Protesters on a Facebook page continue to work for Atangana's release, the radio station said.