Downregulation of huntingtin-associated protein 1 predicts poor prognosis in gastric cancer

Highly expressed in the gastrointestinal mucosa, huntingtin-associated protein 1 (HAP1) is closely associated with tumor development and prognosis.

To investigate the clinical utility of HAP1 expression in gastric cancer (GC).

We randomly selected 124 GC patients had not undergone preoperative radiotherapy or chemotherapy, they were diagnosed at the Central Hospital of Wuhan between May 2013 and October 2018. Immunohistochemistry was used to detect HAP1 expression in paraffin-embedded GC tissues, as well as metastatic lymph nodes. Their clinical data were collected and all participants were follow up for 5 years. Western blotting and quantitative polymerase chain reaction were used to detect HAP1 levels in 20 matched pairs of fresh GC tissues.

HAP1 protein and mRNA levels were lower in fresh GC tissues than in normal mucosal tissues (P < 0.001, respectively). Immunohistochemistry also revealed lower HAP1 expression in GC tissues and metastatic lymph nodes than in normal mucosal tissues (P < 0.05). HAP1 expression in GC was closely associated with differentiation, lymph node metastasis, lymph node ratio, remote metastasis, clinical stage, tumor location, and survival time (P < 0.05). Furthermore, HAP1 expression independently predicted GC (P < 0.05) and was more accurate in advanced GC than in early GC (P < 0.05).

HAP1 is an important prognostic biomarker for GC, with low HAP1 expression positively correlating with poor overall survival, especially in advanced clinical stages.