TGFA and cancer: For cervical cancers with HPV infection, we have constructed the following regression model:(9)ypx=−249.42∗f1x−102.73∗f2x−2.66∗f3x+2.54∗f1x∗f3x+207.09where f1x is the age-dependent distribution of cancer risk, f2x is a continuous function approximating the age-dependent HPV infection rate in the USA, and f3x is the age-dependent distribution of blood level of TGFα, identified to be the sole growth signal specifically needed for this class of cervical cancer.