Compositions, including albumin compositions, which inhibit or reduce epithelial- mesenchymal transition (EMT) are described. In embodiments, such compositions comprise albumin and either i) no pro-EMT agent or a low concentration of pro-EMT agent; ii) a content of pro-EMT agent and anti-EMT agent in a ratio of pro-EMT agent : anti-EMT agent that is from 7:3 to 0:10; or iii) both. The pro-EMT agent is octanoic acid, octanoate salt or a combination thereof. The anti-EMT agent is a C9-C14 fatty acid, a salt of C9-C14 fatty acid, a monoglyceride of C9-C14 fatty acid, a diglyceride of C9-C14 fatty acid, a triglyceride of C9-C14 fatty acid, or a combination thereof. Use of such albumin compositions for various therapeutic applications based on albumin, and more particularly for the treatment of diseases or conditions in which EMT should be prevented or minimized. These albumin compositions can advantageously be used in combination with known active ingredients. Also, described are composition of an anti-EMT agent for use in the treatment of various therapeutic indications, and more particularly for the treatment of diseases or conditions where EMT should be prevented or minimized.Se describen composiciones, lo que incluye composiciones de albúmina, que inhiben o reducen la transición epitelio mesénquima (EMT). En modalidades, tales composiciones comprenden albúmina y ya sea i) ningún agente pro-EMT o una baja concentración de agente pro-EMT; ii) un contenido de agente pro-EMT y agente anti-EMT en una relación de agente pro-EMT:agente anti-EMT que es de 7:3 a 0:10, o iii) ambos. El agente pro-EMT es ácido octanoico, sal de octanoato o una combinación de estos. El agente anti-EMT es un ácido graso C9-CM, una sal de ácido graso C9-CM, un monoglicérido de ácido graso C9-CM, un diglicérido de ácido graso C9-CM, un triglicérido de ácido graso C9-CM o una combinación de estos. El uso de tales composiciones de albúmina para diversas aplicaciones terapéuticas basadas en albúmina