CNR1 and central nervous system cancer: To date, many studies using immunohistochemical staining, Western blotting, qRT-PCR, or a combined method have demonstrated overexpression or expression of CB1R and/or CB2R in human cancers, including glioma [75,76,77,78], lymphoma [82,83], leukemia [84,85], breast [64,65,66,67], lung [60,61], ovarian [86,87], pancreatic [88], prostate [89,90,91], skin [52,92,93] and thyroid cancers [94], endometrial [95], esophageal [96], head and neck [97], hepatocellular [98,99,100], renal [101,102], and mobile tongue carcinomas [39,103].