The development of hepatocellular carcinoma may be regulated by exosome-mediated cell-cell communication. GPC1-enriched exosomes have been associated with malignant phenotypes, while AQP1 has been related to tumor development and metastasis. The functional association of AQP1 and exosomal GPC1 in vivo remains to be clarified. Co-immunoprecipitation was applied to test the interaction of AQP1 with exosomal GPC1 in HCC cells. We generated a mouse xenograft model using control cells and AQP1 knockdown cells, with or without treatment with GPC1-high exosomes. Tumor growth was monitored by longitudinal caliper measurements and endpoint tumor weight. Histology and molecular characteristics were profiled using H phospho-ERK and phospho-MEK display condition-specific differences. Tumor AQP1 staining was markedly greater than that of peritumoral tissue. These data suggest that the AQP1 status may influence tumor sensitivity to GPC1 enriched exosomal stimulation in vivo, and suggest that further analysis of AQP1 as an effector in exosome related oncogenic activity in HCC is warranted.
Qian et al. (Sun,) studied this question.