Smoking is considered a cofactor for the disease to develop. HPV DNA integrates into the host genome. Normally, if the cell DNA is damaged, p53 is in charge of stopping the cell cycle so the DNA can be repaired. Now, if the DNA is altered, the cell keeps replicating. Hm, sounds familiar.
Retinoblastoma normally keeps the cell from growing too fast or responding to growth stimulators.
And so, without these two mechanisms to slow down cell growth and prevent mutation. . . Preventing HPV infection is very difficult. Most infections are asymptomatic, yet transmissible. Also cofactors such as smoking and number of sexual partners can increase the risk of actually developing neoplasias or malignant transformations. Vaccines Vaccines have yet to be developed for Human Papillomavirus.