The present invention provides SERF2, a nucleic acid encoding said SERF2 or a cell expressing SERF2 for use as a medicament, in particular for use for use in treating or preventing an atrophy disease or condition or for increasing cellular growth in a patient such as sarcopenia, cachexia, dystrophy, hypoplasia, hypotonia, or muscle loss, as well as in vitro methods suitable for cell culture proliferation and pharmaceutical compositions.