MD after Ph.D.

Hello
So I have a long way to go before i apply but I wanted to get some opinions. I am going to be starting a Ph.D. in the fall in the sciences,particularly pharmacology. I am an older student 28 and I am interested in applying to Medical School after I finish my Ph.D. I am interested in becoming a physician scientist and focusing my interests in oncology.I would prefer to have both degrees to fully see patients while participating in clinical trials. While i have read that my Ph.D. wont give me a leg up, I am interested to know the application process as far as pre-reqs/ Undergraduate GPA since this is the most important part. Since my pre/reqs sciences are past the 5 year deadline, would they consider just the classes i had to retake because they were out dated or my science career as a whole? Thankfullly the phd allow me to be published and i am able to participate in clinical trials. I am open to applying to DO schools as well. But just would like opinions.

I am pretty ok with the lack of life. By the time i am looking to apply and matriculate, my son will be grown and i'll be on my own...
Thanks