( Leukemias ( ( ( ( ( are ( caused ( by ( ( the proliferation ) ( of ( white ( blood cells ) ) ) ) ) ) ) , ) or ) leukocytes ) . ) )
(ROOT (S (NP (NNS Leukemias)) (VP (VP (VBP are) (VP (VBN caused) (PP (IN by) (NP (NP (DT the) (NN proliferation)) (PP (IN of) (NP (JJ white) (NN blood) (NNS cells))))))) (, ,) (CC or) (VP (VBZ leukocytes))) (. .)))
Leukemias are caused by the proliferation of white blood cells, or leukocytes.
(ROOT (S (NP (JJ Leukocytes) (NN blood) (NNS cells)) (VP (VBP are) (ADJP (JJ white))) (. .)))