Diagnostic and predictive role of cell-free midkine in malignant pleural effusions

mRNA markers associated with malignant pleural effusion

Malignant pleural effusions (MPE) commonly result from malignant tumors and represent advanced-stage cancers. Thus, in clinical practice, early recognition of MPE is valuable. However, the current diagnosis of MPE is based on pleural fluid cytology or histologic analysis of pleural biopsies with a low diagnostic rate. This research aimed to assess the diagnostic ability of eight previously identified Non-Small Cell Lung Cancer (NSCLC)-associated genes for MPE. In the study, eighty-two individuals with pleural effusion were recruited. There were thirty-three patients with MPE and forty-nine patients with benign transudate. mRNA was isolated from the pleural effusion and amplified by Quantitative real-time PCR. The logistic models were further applied to evaluate the diagnostic performance of those genes. Four significant MPE-associated genes were discovered in our study, including Dual-specificity phosphatase 6 (DUSP6), MDM2 proto-oncogene (MDM2), Ring finger protein 4 (RNF4), and WEE1 G2 Checkpoint Kinase (WEE1). Pleural effusion with higher expression levels of MDM2 and WEE1 and lower expression levels of RNF4 and DUSP6 had a higher possibility of being MPE. The four-gene model had an excellent performance distinguishing MPE and benign pleural effusion, especially for pathologically negative effusions. Therefore, the gene combination is a suitable candidate for MPE screening in patients with pleural effusion. We also identified three survival-associated genes, WEE1, Neurofibromin 1 (NF1), and DNA polymerase delta interacting protein 2 (POLDIP2), which could predict the overall survival of patients with MPE.

Diagnostic utility of pleural cell-free nucleic acids in undiagnosed pleural effusions

Pleural effusion (PE) is a common sign caused by various disorders. Microbiology, histology and cytology are reference standards for these disorders. However, these diagnostic tools have limitations, including invasiveness, high cost, long turnaround time, and observer-dependent. Soluble biomarkers in pleural fluid (PF) are promising diagnostic tools because they are mininvasive, economical, and objective. Recent studies have revealed that some cell-free nucleic acids (e.g., DNA, mRNA, microRNA, and lncRNA) in PF are potential diagnostic markers for many disorders. Here, we review the performance of PF cell-free nucleic acids for differentiating and stratification of PE.

The diagnostic value of CEA for lung cancer-related malignant pleural effusion in China: a meta-analysis

Objective: To accurately evaluate the diagnostic value of carcinoembryonic antigen (CEA) for malignant pleural effusion associated with lung cancer in the Chinese population.Methods: Three English databases, PubMed, Embase and Web of Science, and two Chinese databases, China National Knowledge Infrastructure (CNKI) and Wanfang Data, up to 5 November 2020, were searched. The literature on the diagnosis of lung cancer-related malignant pleural effusion by CEA in the Chinese population were collected. The data was analyzed by Stata15.0 software.Results: A total of 15 studies were included in the meta-analysis. The combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio were 0.80 (95% CI: 0.74-0.84), 0.92 (95% CI: 0.89-0.95), 10.46 (95% CI: 7.29-15.00), 0.22 (95% CI: 0.17-0.28), 47.26 (95% CI: 28.84-77.44), respectively . The area under the receiver operating characteristic curve was 0.93 (95% CI: 0.91-0.95). No significant publication bias was found (P > 0.05)Conclusion: CEA has anexcellent diagnostic value for patients with lung cancer-related malignant pleural effusion in the Chinese population.

Midkine is a potential novel marker for malignant mesothelioma with different prognostic and diagnostic values from mesothelin

Background

We evaluated possible diagnostic and prognostic values of serum midkine in malignant pleural mesothelioma in comparison with those of serum mesothelin, a well-established diagnostic biomarker.

Methods

Serum mesothelin and midkine levels were determined with an enzyme-linked immunosorbent assay. We examined specimens from 95 Turkish cases with malignant pleural mesothelioma, 56 metastatic cancers to pleura, 27 other types of benign pleural diseases and 20 benign asbestos pleurisy. The cut-off values were 1.5 nmol/L for mesothelin and 421 pg/mL for midkine.

Results

Sensitivity and specificity of mesothelin were 51.6 and 71.4%, 51.6 and 85.2%, and 51.6 and 85% for differentiating mesothelioma from metastatic cancers to pleura, other benign pleural diseases and benign asbestos pleurisy, respectively. Sensitivity and specificity of midkine were 61.1 and 41.1%, 61.1 and 48.1%, and 61.1 and 75% to distinguish mesothelioma from metastatic cancers to pleura, other benign pleural diseases and benign asbestos pleurisy, respectively. Combination of both biomarkers did not improve the differential diagnostic efficacy. Mesothelin levels were elevated in the epitheloid type and in the advanced cases, but were not related to the prognosis. In contrast, elevated baseline levels of midkine were independently associated with a poor prognosis of mesothelioma patients after adjusting for the stage, the histological subtypes and treatment schedules (HR = 1.84; 95% CI: 1.09-3.09) (p = 0.022).

Conclusions

Serum mesothelin showed moderate sensitivity and high specificity to differentiate malignant pleural mesothelioma from metastatic malignancy to pleura and from benign pleural diseases. In contrast, midkine was a useful marker for predicting prognosis of mesothelioma patients.

MDK Protein Overexpression Correlates with the Malignant Status and Prognosis of Non-small Cell Lung Cancer

BACKGROUND AND AIMS

Midkine (MDK) is a heparin-binding growth factor and is overexpressed in various types of human cancer. However, little is known about the clinical significance of MDK in non-small cell lung cancer (NSCLC). The aim of this study was to measure MDK protein levels in patients with NSCLC and to explore its clinical significance.

METHODS

The expression status of MDK in NSCLC at Gene Expression Omnibus (GEO accession number: GSE19804) was observed. The expression of MDK mRNA and protein was examined in NSCLC tissues and normal lung tissues through real-time PCR and Western blot. Meanwhile, the relationship of MDK protein expression levels with clinical characteristics of 186 NSCLC patients was analyzed by immunohistochemistry.

RESULTS

MDK expression was increased in NSCLC tissues compared with paired normal lung tissues in microarray data (GSE19804). MDK mRNA and protein expression were obviously increased in NSCLC tissues than in paired adjacent normal lung tissues. Using immunohistochemistry, MDK protein overexpression was positively correlated with status of clinical stage, T classification, N classification, and M classification in NSCLC patients. In survival analysis, patients with higher MDK protein expression had a significantly shorter overall survival time than did patients with lower MDK protein expression. Multivariate analysis indicated that the MDK protein overexpression was an independent poor prognostic indicator for patients with NSCLC.

CONCLUSIONS

MDK plays an important role in NSCLC progression and prognosis and may act as a convincing prognostic indicator for NSCLC patients.

Itraconazole can inhibit malignant pleural effusion by suppressing lymphangiogenesis in mice

BACKGROUND

The presence of malignant pleural effusion (MPE) indicates a poor prognosis in patients with non-small cell lung cancer (NSCLC). Itraconazole has been identified as a potent inhibitor of endothelial cell proliferation that suppresses angiogenesis; however, its role in the suppression of lymphangiogenesis is still unclear. The aim of this study was to investigate the efficacy of itraconazole for MPE and the mechanism of lymphangiogenesis suppression.

METHODS

Lewis lung carcinoma (LLC) cells were injected into the mouse pleural cavity to establish the MPE mouse model, followed by randomization of the mice into three groups. Each mice was injected with either a high dose of itraconazole (25 mg/kg, H-ITCZ), a low dose of itraconazole (8 mg/kg, L-ITCZ), or 50 μL of hydroxypropyl-β-cyclodextrin (130 mg/mL, H-β-C) into the pleural cavity four times every 3 days. The MPE of the mice was collected and measured with a 1 mL syringe. The vascular endothelial growth factor-C (VEGF-C) expression level in the MPE was detected by enzyme-linked immunosorbent assay (ELISA), while the VEGF-C expression and lymphatic micro vessel density (LMVD) in the tumor tissue was observed by immunohistochemistry (IHC) staining.

RESULTS

The number of pleural tumor foci, the volume of pleural effusion, the LMVD and the VEGF-C expression levels in the tumor tissue were significantly reduced in the H-ITCZ-treated group.

CONCLUSIONS

Our results revealed that itraconazole may play an important role in the MPE mice by suppressing lymphangiogenesis, which demonstrated the usefulness of itraconazole in the treatment of MPE.