Light elements lithium, beryllium and boron (LiBeB) were used in the last years as "possible probe" for a deeper understanding of some extra-mixing phenomena occurring in young Main-Sequence stars. They are mainly destroyed by (p,a) reactions and cross section measurements for such channels are then needed. The Trojan Horse Method (THM) allows one to extract the astrophysical S(E)-factor without the experience of tunneling through the Coulomb barrier. In this work a resume of the recent results about the B-11(p,alpha(0))Be-8 and B-10(p,alpha)Be-7 reactions is shown.