Long non-coding RNA HOTAIR promotes cancer cell energy metabolism in pancreatic adenocarcinoma by upregulating hexokinase-2

Hox transcript antisense RNA (HOTAIR) is a long non-coding RNA (IncRNA) that serves a key role in the pathogenesis of various types of cancer, including pancreatic adenocarcinoma. However, the diagnostic and prognostic values of HOTAIR in pancreatic adenocarcinoma, as well as its involvement in cancer cell energy metabolism, remain unclear. In the present study, tumor tissues and adjacent healthy tissues were collected from patients with pancreatic adenocarcinoma, and blood samples were collected from patients and healthy controls. Expression levels of HOTAIR and hexokinase-2 (HK2) were detected by reverse transcription-quantitative polymerase chain reaction. All patients were followed up for 5 years, and the diagnostic and prognostic values of serum HOTAIR levels were investigated by receiver operating characteristic curve and survival analyses, respectively. Pancreatic adenocarcinoma cell lines overexpressing HOTAIR and HK2 were established, and the effects on cell proliferation, lactate production, glucose uptake and ATP production were detected by Cell Counting Kit-8, lactate, glucose uptake and ATP assays, respectively. The protein expression was detected by western blot analysis. The results revealed that HOTAIR and HK2 expression levels were increased in tumor tissues compared with adjacent healthy tissues. The serum levels of HOTAIR and HK2 were higher in patients with pancreatic cancer compared with healthy controls. The serum levels of these two factors may be used to accurately predict pancreatic adenocarcinoma and its prognosis. HOTAIR and HK2 overexpression led to the promotion of tumor cell proliferation. HOTAIR overexpression increased lactate production, glucose uptake and ATP production. Furthermore, it promoted HK2 expression, however HK2 overexpression displayed no significant effects on HOTAIR expression levels. Therefore, it was concluded that the lncRNA HOTAIR may promote cancer cell energy metabolism in pancreatic adenocarcinoma by upregulating HK2. Key words; pancreatic adenocarcinoma, energy metabolism, pancreatic cancer