Abstract: In the present disclosure, the effect of the TGF?/Smad3/EPB41L5 molecular mechanism on cancer cells has been identified, and it has been found that high expression of EPB41L5 is correlated with poor overall survival of cancer patients, indicating that EPB41L5 is a potential prognostic marker of cancer. Thus, the present disclosure specifies an epitope of EPB41L5 to allow EPB41L5 to be recognized as an antigen, and relates to an antibody or a fragment thereof which binds specifically to the epitope. The antibody according to the present disclosure may be usefully employed as a therapeutic agent for EPB41L5-related cancer.