reference index of lymph node in central region.

Long non-coding RNAs (lncRNAs) are a kind of transcripts which are longer than 200nt and have not protein-coding ability due to the lack of an open reading frame. However, lncRNAs can be involved in tumorigenesis and progression in various ways at the transcriptional and post-transcriptional levels. Bladder cancer associated transcript 1 (BLACAT1) as a lncRNA located on human chromosome 1q32.1, is ectopic expression in various tumors (bladder cancer, gastric malignant tumor, lung carcinoma, et al) and can regulate tumor cell proliferation, anti-apoptosis, invasion and metastasis by different mechanisms leading to occurrence and development of tumors. In this review, we summarized current studies of the functions and mechanisms of BLACAT1 in malignant tumors.

The insidious onset of cholangiocarcinoma and the lack of early diagnosis markers have made most patients diagnosed with cholangiocarcinoma in the advanced stage of the disease. At present, surgical treatment is the first choice for patients with cholangiocarcinoma, but surgery also faces problems such as high risks and many difficulties. Recent studies have found that long non-coding RNA (lncRNA) and circular RNA (circRNA) have the functions of regulating the cell proliferation, metastasis, invasion, epithelial-mesenchymal transition and drug resistance of cholangiocarcinoma. This article aims to review the potential regulatory role of lncRNA and circRNA in the occurrence and development of cholangiocarcinoma, in order to provide clinical references for the early diagnosis, targeted therapy and patient's prognosis evaluation of cholangiocarcinoma.

ObjectiveTo investigate the expression level of lysophosphatidyllecithin acyltransferase 4 （LPCAT4） in pancreatic cancer and its effect on the proliferation of pancreatic cancer cells. MethodsIn this study， the differentially expressed genes of patients with KRAS mutant and wild-type pancreatic cancer were analyzed by online database LinkedOmics. The LPCAT4 expression in pancreatic cancer tissues was analyzed online by the University of Alabama at Birmingham Cancer Data Analysis （UALCAN）， Sangerbox and gene expression profile interaction analysis 2 （GEPIA2）. Kaplan-Meier Plotter database was used to explore the correlation between LPCAT4 and the prognosis of patients with pancreatic cancer. The expression of LPCAT4 in human pancreatic cancer cells were detected by quantitative real-time PCR and Western blot analysis. LPCAT4 was knocked down in the high-expressing SW1990 cell line and overexpressed in the low-expressing MIA PaCa-2 cell line. The effects of LPCAT4 expression on cell proliferation were assessed using CCK-8 and EdU assays. STRING and GEPIA2 databases were used to obtain LPCAT4 binding and coexpressed genes in tumors， which were then analyzed by GO and KEGG. ResultsAnalysis of the LinkedOmics online database revealed a significant upregulation of LPCAT4 in patients with KRAS mutant pancreatic cancer compared to patients with KRAS wild-type pancreatic cancer. The online analysis of GEPIA2， UALCAN and Sangerbox 3.0 showed that the expression of LPCAT4 was higher in pancreatic cancer than in normal tissues. Analysis of the Kaplan-Meier Plotter database revealed that high LPCAT4 expression was associated with poorer prognosis in pancreatic cancer patients.Western blot and qPCR results showed that expression of LPCAT4 in pancreatic cancer cell lines was significantly higher than in normal pancreatic ductal epithelial cells. Knockdown of LPCAT4 in SW1990 cells inhibited proliferation， while overexpression in MIA PaCa-2 cells promoted proliferation. Enrichment analysis indicated that LPCAT4 was closely related to sulfur metabolism. ConclusionsLPCAT4 is highly expressed in pancreatic cancer and is associated with poor prognosis of patients. It plays a significant regulatory role in the proliferation of pancreatic cancer cells， with its expression level closely correlated with cell proliferation capacity. These findings reveal the critical role of LPCAT4 in the malignant progression of pancreatic cancer and provide important evidence for its potential as a therapeutic target.