Maternal embryonic leucine zipper kinase: A novel biomarker and a potential therapeutic target in lung adenocarcinoma.

Maternal embryonic leucine zipper kinase (MELK), is an adenosine monophosphate-activated protein kinase-related kinase that serves important roles in tumourigenesis in multiple malignant tumours. However, to the best of our knowledge, the effect of MELK in lung adenocarcinoma (LUAD) has not been elucidated. The present study aimed to explore the clinical significance of MELK in the prognosis of LUAD. Data from Oncomine, Gene Expression Profiling Interactive Analysis (GEPIA) and The Cancer Genome Atlas (TCGA) were selected to predict the differential mRNA expression levels of MELK mRNA in LUAD and normal tissues. Subsequently, LUAD and adjacent normal tissue samples were collected from 75 patients with the disease, and immunohistochemistry was used to detect the protein expression of MELK. In addition, the Kaplan-Meier Plotter database, GEPIA and TCGA were used to verify the effect of MELK expression on clinical prognosis in patients with LUAD. MELK was significantly upregulated in LUAD tissues compared with that in normal tissues based on Oncomine, GEPIA and TCGA data (P<0.05). In addition, the results from immunohistochemistry demonstrated that the MELK protein level in LUAD tissues was significantly higher compared with that in matched normal tissues (P<0.05). Prognostic analysis performed using the Kaplan-Meier plotter, GEPIA and TCGA suggested that the expression of MELK was negatively associated with the overall survival time of patients with LUAD (P<0.05). In conclusion, MELK was highly expressed in LUAD based on bioinformatics and immunohistochemistry analysis, and increased expression of MELK was associated with a poor patient prognosis. MELK may serve as a potential diagnostic marker and therapeutic target for LUAD.

The expression and prognostic significance of Drp1 in lung cancer: A bioinformatics analysis and immunohistochemistry.

BACKGROUND: Dynamin-related protein 1 (Drp1) plays important roles in tumorigenesis, including lung cancer. However, the effect of Drp1 in lung cancer remains unclear. The present study was aimed to investigate the clinical significance and effect of Drp1 on prognosis of lung cancer. METHODS: Oncomine and The Cancer Genome Atlas (TCGA) databases were selected to predict the differential expression levels of Drp1 in lung cancer. Then, 70 cases of lung cancer and normal tissues were collected and immunohistochemistry was used to detect the expression of Drp1. In addition, Kaplan-Meier Plotter database and TCGA database were used to verify the correlation between Drp1 expression and the clinical prognosis in lung cancer patients. RESULTS: Drp1 was significantly overexpressed in lung cancer tissues based on Oncomine and TCGA databases (P < .05). Moreover, results from immunohistochemistry showed that Drp1 protein level in lung cancer was also significantly higher than that in the matched normal tissues (P < .05). Prognostic analysis from Kaplan-Meier Plotter database with the chosen probe IDs of 203105_s_at suggested that Drp1 was negatively correlated to overall survival (OS) of lung cancer patients (HR = 1.16, 95% CI: 1.02-1.31; P = .025), but not in the probe IDs of 226154_at (HR = 0.86, 95% CI: 0.73-1.01; P = .069). However, prognosis from TCGA database showed inconsistent results in which high expression of Drp1 was correlated with worse survival probability of all, male, female in lung adenocarcinoma (P < .05), but not in LUSC (P > .05). CONCLUSION: Drp1 was highly expressed in lung cancer based on bioinformatics analysis and tissue microarray, but there was a lot of inconsistency in prognosis depending on different levels of Drp1 from the bioinformatics analysis.