The present invention relates to proteins comprising amino acid sequences encoded by nucleic acids derived from the human chromosomal region C19Orf10 termed Factor1 and/or C19Orf63 termed Factor 2 for the use in enhancing proliferation and/or healing and/or inhibiting apoptosis of none-transformed tissue or none-transformed cell or inhibitors thereof. The invention further relates to the use of inhibitors of factor1 and factor 2 for medical use, preferably for use in treating or preventing a disease in which angiogenesis contributes to disease development or progression.