AKR1B1 VE AKR1B10 aşırı ifadelenmesinin kolorektal kanser hücre hatları üzerindeki fonksiyonel etkilerinin değerlendirilmesi

Aldo-keto reductases (AKRs) are nicotinamide adenine dinucleotide phosphate (NADPH)-dependent enzymes with diverse cellular metabolism functions. AKR1B1 and AKR1B10 are two of the most studied enzymes in the AKR family. AKR1B1 reduces excess glucose into sorbitol using reducing electrons from NADPH, and the hyperactivation of the AKR1B1 pathways is associated with oxidative stress and cell death. AKR1B10 is a poor reductant of glucose but is a vital enzyme that can metabolize retinol and many other drugs and therefore is implicated in cancer development. Our previous research has shown that high expression of AKR1B1 and AKR1B10 in colorectal cancer can have divergent effects. Thus, while high expression of AKR1B1 was associated with a strong epithelial to mesenchymal (EMT) and pro-inflammatory phenotype, high expression of AKR1B10 showed activation of nutrient-sensing pathways. In order to better understand the functional effects and underlying cellular signaling pathways, we overexpressed both enzymes in cell lines RKO and SW480 that do not endogenously express AKR1B1 or AKR1B10. Functional assays showed no significant alterations in cellular proliferation in 2D cell culture, which was also reflected in no alterations in colony formation capacity. AKR1B10 overexpressing cells had a greater vulnerability to serum starvation reflected by a high number of cells arrested in the G1 phase of the cell cycle. AKR1B1 overexpressing cells compared to AKR1B10 overexpressing cells showed significantly higher motility, confirming our previous data. RNA sequencing of AKR1B1 and AKR1B10 overexpressing RKO cells indicated that gene ontology (GO) terms previously established in high AKR1B1 or AKR1B10 expressing tumor samples (that have an expression from both epithelial and stromal compartments) overlapped with the GO terms obtained in RKO cells. Thus, high AKR1B1 overexpressing cells were significantly associated with ROS-related processes, whereas AKR1B10 overexpressing cells were significantly associated with the inhibition of metabolic and biosynthetic processes.