A Sensitive IHC Method for Monitoring Autophagy-Specific Markers in Human Tumor Xenografts

Figure 5

Xenograft tissues of multiple tumor types were randomly selected and stained in triplicate using LC3B and NBR1 Amp HQ IHC assays. (a) Whole slide image analysis was performed using positive pixel count. All values are expressed as the mean ± SD. The data show that the average basal expression of LC3B and NBR1 varied between tumors and the ratio of LC3B to NBR1 signal levels is not consistently proportional across the samples tested. U87 MG, SKOV-3, and H1975 xenograft tumors showed higher levels of LC3B compared to NBR1 in the same tumors. Conversely, A375, LuCap105, CWR22, H1650, HCT116, MDA-MD-361, MM1.S, and HT-29 xenograft tumors showed higher levels of NBR1 relative to LC3B. The remaining xenograft tumors were separated into groups having either relatively equivalent LC3B and NBR1 signals, including OCI-LY10, MDA-MB-231, WSU-DLCL2, ES2, and SW48, or very low expression of both markers including HL60, A549, and THP-1 xenograft tumors. (b) Representative images of LC3B and NBR1 stained xenograft tissues.

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