Receptor of activated C Kinase 1 (RACK1) is an essential scaffold and anchoring
protein, which serves an important role in multiple
tumorigenesis signaling pathways. The present study aimed to investigate the expression of RACK1 in
gastric cancer (GC), and its association with the occurrence and development of GC. In addition, the effect and mechanism of RACK1 overexpression on the growth, and proliferation of GC cells was examined. Firstly, the
protein expression of RACK1 was detected in 70 cases of GC tissues and 30 cases of noncancerous tissues using immunohistochemical staining, and the association between clinical and pathological features of GC was analyzed. Secondly, the
mRNA and
protein expression of RACK1 was determined in the poorly-differentiated human
gastric cancer cell line HGC27 and gastric epithelial cell line GES-1. The growth of HGC27 cells following the upregulation of RACK1 was detected using MTT method. Subsequently, the interaction and co-location between RACK1, and WEE1 homolog (S. pombe) (WEE1) in HGC27 cells was confirmed using co-immunoprecipitation and indirect immunofluorescence. The expression level of RACK1 in GC was significantly lower compared with that in pericarcinous tissues (P<0.05). The
protein level of RACK1 expression correlated with
tumor node
metastasis stage,
tumor differentiation and
lymph node metastasis. The
mRNA and
protein levels of RACK1 in HGC27 cells were significantly reduced, and overexpressed RACK1 downregulated WEE1
protein expression, thus inhibiting the growth of HGC27 cells. Co-immunoprecipitation and immunofluorescence confirmed that RACK1, and WEE1 interacted and co-located in the cytoplasm of HGC27 cells. Therefore, the abnormal expression of RACK1 in GC tissues was identified to be involved in the occurrence and development of GC. Overexpression of RACK1 was able to inhibit the growth of HGC27 cells. The current study suggests that low expression of RACK1 is an important
indicator of poor prognosis of GC. RACK1 and WEE1 interact to regulate the growth of HGC27 cells.