rationalskepticism.org

Writings attributed to Justin Martyr and Celsus support the argument that Marcion knew nothing of the Pauline epistles and that he [Marcion] preached or wrote nothing about Jesus.

Justin was a contemporary of Marcion and the writings attributed to him specifically state that Marcion preached about ANOTHER GOD and ANOTHER SON.

http://earlychristianwritings.com/text/justinmartyr-firstapology.html

Firtst Apology XXVI

And there is Marcion, a man of Pontus, who is even at this day alive, and teaching his disciples to believe in some other god greater than the Creator.

And he, by the aid of the devils, has caused many of every nation to speak blasphemies, and to deny that God is the maker of this universe, and to assert that some other being, greater than He, has done greater works.

And, as we said before, the devils put forward Marcion of Pontus, who is even now teaching men to deny that God is the maker of all things in heaven and on earth, and that the Christ predicted by the prophets is His Son, and preaches another god besides the Creator of all, and likewise another son.

And this man many have believed, as if he alone knew the truth, and laugh at us......

The writing attributed to Celsus "True Discourse" also confirms that Paul and the Jesus story in Pauline letters were unknown up to at least the last quarter of the 2nd century.

The writing "Against Celsus" attributed to Origen admits that Celsus wrote nothing of Paul.

http://newadvent.org/fathers/04161.htm

Against Celsus 1.63

And I do not know how Celsus should have forgotten or not have thought of saying something about Paul, the founder, after Jesus, of the Churches that are in Christ.