Figure 2

Menin expression is inactivated in prostate cancers from Men1 ^+/- mice. Microscopic images of prostate glands from Men1 ^+/+ (A) and Men1 ^+/- mice (B-I) subjected to menin detection by IHC. Menin is widely expressed in the nuclei of prostate epithelial cells in the lateral (LP), dorsal (DP), ventral (VP) and anterior (AP) prostate from a 21-month-old Men1 ^+/+ mouse (A), but is completely inactivated in two of four tested mPINs and in all six prostatic cancerous lesions in Men1 ^+/- mice. Four representative types of lesions are shown: mPIN from a 21-month-old Men1 ^+/- mouse (B, F), an in situ prostate carcinoma from a 26-month-old mouse (C, G), a well-differentiated adenocarcinoma from a 23-month-old mouse (D, H) and a papillary adenocarcinoma from a 23-month-old mouse (E, I). Panels F-I are two-fold magnifications of the upper panels (B-E). Insets show an amplified view of a part of the prostate glands. Scale bars, 50 μm. (J) Representative results from two independent LOH analyses of prostatic lesions in Men1 ^+/- mice. Semi-quantitative amplification of Men1 wild-type (+) and mutant (-) alleles with PCR was performed on DNA samples extracted from microdissected paraffin-embedded sections from Men1 ^+/+ normal prostate (WT) and prostate lesions from Men1 ^+/- mice, including two mPIN (PIN1 and PIN2) and one adenocarcinoma (ADC). Tail DNA from wild-type (+/+) and heterozygous (+/-) Men1 mice were used as controls. The intensity of both alleles (+ and -) was quantified and used to calculate the +/- ratio, which was compared with the +/- ratio obtained from the controls.