CDCA3 is a potential prognostic marker that promotes cell proliferation in gastric cancer.

Gastric cancer (GC) is an aggressive and highly lethal gastrointestinal cancer, with an exceedingly poor prognosis. In the present study, the carcinogenic mechanism of human GC and the role of cell division cycle‑associated 3 (CDCA3) were investigated. The expression levels of CDCA3 were investigated in GC samples and matched, peritumoral tissues by reverse transcription‑quantitative polymerase chain reaction and immunohistochemical analysis. The effects of CDCA3 on cell proliferation were explored by Cell Counting Kit‑8, colony formation, flow cytometric analysis and western blotting in vitro, and in vivo tumorigenesis in nude mice. The results demonstrated that CDCA3 expression was increased in human GC tissues compared with those in adjacent non‑tumor tissues. Evaluation of the clinicopathological significance indicated that CDCA3 was closely associated with features of GC and patients with unfavorable overall survival times. CDCA3 overexpression resulted in the stimulation of cell growth and colony formation in vitro and xenograft tumors in vivo. Conversely, knockdown of CDCA3 inhibited these effects. Furthermore, the ectopic expression of CDCA3 in SGC7901 cells consistently promoted the cell cycle transition from the G0/G1 phase to the S phase; whereas knockdown of CDCA3 in BGC823 cells blocked the transition from the G0/G1 phase. Additionally, the present study revealed that the Ras signaling pathway was involved in CDCA3‑mediated regulation of GC cell proliferation. CDCA3 activated the Ras signaling pathway to promote cell proliferation in vitro and in vivo in GC cells. Levels of CDCA3 greatly accelerated the progression of human GC. CDCA3 served as an oncogene, and may be a significant prognostic predictor and a novel therapeutic target for patients with GC.