High expression of fructose-bisphosphate aldolase A induces progression of renal cell carcinoma.

Aldolase A (fructose-bisphosphate aldolase A, ALDOA) is a glycolytic enzyme that catalyzes reversible conversion of fructose‑1,6-bisphosphate to glyceraldehyde 3-phosphate and dihydroxyacetone phosphate. ALDOA has been revealed to be related with many carcinomas, but its expression and function in renal cell carcinoma (RCC) remain unknown. This study aimed to detect expression of ALDOA in human RCC tissue samples and to explore its function in RCC cell lines. Reverse transcription-polymerase chain reaction was used to quantify ALDOA in human RCC samples. A total of 139 RCC tissue samples obtained after surgery were analyzed in tissue microarray for ALDOA immunohistochemistry-based protein expression. Assays for cell cycle, viability, migration, and invasion were performed to assess phenotypic changes in RCC cells after ALDOA knockdown by small interfering RNA-mediated gene silencing approach and ALDOA upregulation by overexpression plasmids. Western blot analysis was used to identify alterations in markers for epithelial-mesenchymal transition (EMT), which affects metastasis and the Wnt/β‑catenin signaling pathway that influences RCC cell growth. ALDOA was upregulated in RCC samples and RCC cell lines (P<0.01). Expression of ALDOA was significantly associated with metastasis (P=0.020) and survival (P=0.0341). Downregulation of ALDOA suppressed proliferation (P<0.05) by triggering G0/G1 cell cycle arrest (P<0.05) and also inhibited migration (P<0.05) and invasion (P<0.01). Upregulation of ALDOA promoted proliferation (P<0.05) and enhanced migration (P<0.001) and invasion (P<0.001). Low expression of ALDOA could reverse EMT and inactivate the Wnt/β‑catenin signaling pathway. Our data revealed that ALDOA functions as a tumor promoter, plays a prominent role in proliferation, migration, and invasion of RCC cells with high expression, and may promote EMT and activate the Wnt/β‑catenin signaling pathway.