CB1a can inhibit the growth of lung tumors in an <i>in</i><i>vivo</i> mouse model.

<p>Six mice were subcutaneously pre-treated with CB1a (50 mg/kg) for one week prior to them being subcutaneously xenografted with human tumorigenic NCI-H460 lung cancer cells (0.2 ml; 1×10⁶ cells/ml). A control was studied in which saline was used instead of CB1a (6 mice in this control group). (<i>A</i>) The CB1a/saline injection point was in the dorsolateral neck area (arrow labelled <i>Ia</i>) and the cancer cells were transplanted to the abdominal flank area of the mouse (arrow labelled <i>Ib</i>). The ruler shows that these points are ∼4 cm apart, which is long relative to the length of the mouse (∼6 cm). (<i>B</i>) Mean body weight (g) vs. time (days); the mean body weight of CB1a treated mice (triangles) was comparable to that of saline treated mice (circles), which indicates that CB1a is not overly toxic to normal cells. (<i>C</i>) Mean tumor volume (mm³) vs. time (days) for CB1a (triangles) or saline (circles) treated mice. The tumor is much smaller in CB1a treated mice; after 36 days the mean tumor volume in CB1a treated mice is just 19.3% of that in saline treated mice. (<i>D</i>) The mice were sacrificed on day 36 in order for their tumors to be weighed. Mean tumor weight in saline treated mice normalized as 1.0; the mean tumor weight of CB1a treated mice is just 9% of this value.