VPS53 and neoplasm: We examined the expression of the adenovirus capsid protein hexon and HCCS1 (via an HA-tag-specific antibody) by immunohistochemical staining, and we found significant positive staining by hexon-specific antibody in the adenoviruses treated groups, but only Ad.SPDD-HCCS1HA infected tumor shows positive staining by HA tag-specific antibody (Figure 4C).