Ramat-Gan, Israel: The primary psychoactive agent in cannabis, THC, possesses anti-tumoral activity in glioblastoma multiforme (GBM) cell lines and should be evaluated in clinical trials as a treatment for brain cancer, according to preclinical data to be published in the journal Acta Oncologica.

Investigators at Bar-Ilan University in Israel report that the administration of THC significantly affects the viability of GBM cells. Glioblastoma multiforme, the most aggressive form of glioma (brain cancer), strikes some 7,000 Americans annually, and generally results in death within one to two years following diagnosis.

"THC [is] an essential mediator of cannabinoid antitumoral action," investigators concluded. "Administration of Delta(9)-THC to glioblastoma multiforme (GBM) cell lines results in a significant decrease in cell viability. … [I]t is suggested that Delta(9)-THC and other cannabinoids be implemented in future clinical evaluation as a therapeutic [agent] for brain tumors."

In 2006, investigators at Complutense University in Spain reported that the intracranial administration of THC decreased recurrent GBM tumor growth in humans.

Separate preclinical studies indicate that cannabinoids can inhibit the proliferation of various cancer cell lines, including breast carcinoma, prostate carcinoma, lung cancer, and lymphoma.

Full text of the study, "Delta9-Tetrahydrocannabinol inhibits cell cycle progression by downregulation of E2F1 in human glioblastoma multiforme cells," will appear in Acta Oncologica. Additional information on the anti-cancer properties of cannabis is available in NORML’s booklet, "Emerging Clinical Applications for Cannabis and Cannabinoids," available online at: http://norml.org/index.cfm?Group_ID=7002.