Born in Buenos Aires, Juan Carlos Colombres abandonned his architecture studies for journalism and humorous cartooning. His first cartoon appeared in the magazine Don Fulgencio in 1945. His first political drawing appeared in Cascabeles in 1946. One of Colombres' colleagues told him that he resembled the famous French assassin Landru. From then on, Colombres signed his work "Landrú". Colombres contributed to Rico Tipo, Vea y Lea, Pobre Diabolo, Paturuzú, Avivato and Mundo Argentino.
In 1957, he launched the magazine Tia Vicenta, a magazine with political humor in which he satirized the customs and the speech of the Argentine society. Among his many characters are the title character 'Tia Vicenta', 'Diogenes el Curandero', 'Rogelio el Hombre que Razonava Demasiando', 'El Detective Cuculiu', 'Rudy el Play Boy' and 'Fofoli un Niño Abominable'. During the 1960s, Landrú had problems with censorship, which led to the cancellation of Tia Vicenta. Landrú returned in 1968 with the shortlived magazine Tio Landru.