The present disclosure provides a novel antineoplastic extract obtained from Deschampsia antarctica plant. Active components of the antineoplastic extract are also disclosed and a method to prevent proliferation of cancerous or tumorous cells with the extract or with components thereof is disclosed. Furthermore, a method to induce production of active ingredients in in vitro grown plants by submitting the plants to physical or chemical treatements before preparing the antineoplastic extract is disclosed. This disclosure provides compostions of tablets and pellets for treating patients with cancer or for prevention of occurence of cancerous diseases.
