We prove that a finitely generated pro-p group acting on a prop tree T with procyclic edge stabilizers is the fundamental pro-p group of a finite graph of pro-p groups with edge and vertex groups being stabilizers of certain vertices and edges of T respectively, in the following two situations: 1) the action is n-acylindrical, i.e., any non-identity element fixes not more than n edges; 2) the group G is generated by its vertex stabilizers. This theorem is applied to obtain several results about pro-p groups from the class L defined and studied in [16] as pro-p analogues of limit groups. We prove that every pro-p group G from the class L is the fundamental pro-p group of a finite graph of pro-p groups with infinite procyclic or trivial edge groups and finitely generated vertex groups; moreover, all non-abelian vertex groups are from the class L of lower level than G with respect to the natural hierarchy. This allows us to give an affirmative answer to questions 9.1 and 9.3 in [16]. Namely, we prove that a group G from the class L has Euler-Poincaré characteristic zero if and only if it is abelian, and if every abelian pro-p subgroup of G is procyclic and G itself is not procyclic, then def(G) ≥ 2. Moreover, we prove that G satisfies the Greenberg-Stallings property and any finitely generated non-abelian subgroup of G has finite index in its commensurator.We also show that all non-solvable Demushkin groups satisfy the Greenberg-Stallings property and each of their finitely generated non-trivial subgroups has finite index in its commensurator.