ELMO3 predicts poor outcome in T1 laryngeal cancer

Identification and analysis of key genes related to efferocytosis in colorectal cancer

The impact of efferocytosis-related genes (ERGs) on the diagnosis of colorectal cancer (CRC) remains unclear. In this study, efferocytosis-associated biomarkers for the diagnosis of CRC were identified by integrating data from transcriptome sequencing and public databases. Finally, the expression of biomarkers was validated by real-time quantitative polymerase chain reaction (RT-qPCR). Our study may provide a reference for CRC diagnosis.

BACKGROUND

It has been shown that some efferocytosis related genes (ERGs) are associated with the development of cancer. However, it is still uncertain how ERGs may influence the diagnosis of colorectal cancer (CRC).

METHODS

In our study, the CRC cohorts were gained from transcriptome sequencing and the gene expression omnibus (GEO) database (GSE71187). Efferocytosis related biomarkers with diagnostic utility for CRC were identified through combining differentially expressed analysis, machine learning algorithms, and receiver operating characteristic (ROC) analysis. Then, infiltration abundance of immune cells between CRC and control was evaluated. The regulatory networks (including mRNA-miRNA-lncRNA and miRNA/transcription factors (TF)-mRNA networks) were created. Finally, the expression of biomarkers was validated via real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

There were 3 biomarkers (ELMO3, P2RY12, and PDK4) related diagnosis for CRC patients gained. ELMO3 was highly expressed in CRC group, while P2RY12 and PDK4 was lowly expressed. Besides, the infiltrating abundance of 3 immune cells between CRC and control groups was significantly differential, namely activated CD4 memory T cells, macrophages M0, and resting mast cells. We then constructed a mRNA-miRNA-lncRNA network containing 3 mRNAs, 33 miRNAs, and 22 lncRNAs, and a miRNA/TF-mRNA network including 3 mRNAs, 33 miRNAs, and 7 TFs. Additionally, RT-qPCR results revealed that the expression trends of all biomarkers were consistent with the transcriptome sequencing data and GSE71187.

CONCLUSION

Taken together, this study provides three efferocytosis related biomarkers (ELMO3, P2RY12, and PDK4) for diagnosis of CRC, providing a scientific reference for further studies of CRC.

Comparative Morphological, Metabolic and Transcriptome Analyses in elmo1−/−, elmo2−/−, and elmo3−/− Zebrafish Mutants Identified a Functional Non-Redundancy of the Elmo Proteins

The ELMO protein family consists of the homologues ELMO1, ELMO2 and ELMO3. Several studies have shown that the individual ELMO proteins are involved in a variety of cellular and developmental processes. However, it has poorly been understood whether the Elmo proteins show similar functions and act redundantly. To address this question, elmo1−/−, elmo2−/− and elmo3−/− zebrafish were generated and a comprehensive comparison of the phenotypic changes in organ morphology, transcriptome and metabolome was performed in these mutants. The results showed decreased fasting and increased postprandial blood glucose levels in adult elmo1−/−, as well as a decreased vascular formation in the adult retina in elmo1−/−, but an increased vascular formation in the adult elmo3−/− retina. The phenotypical comparison provided few similarities, as increased Bowman space areas in adult elmo1−/− and elmo2−/− kidneys, an increased hyaloid vessel diameter in elmo1−/− and elmo3−/− and a transcriptional downregulation of the vascular development in elmo1−/−, elmo2−/−, and elmo3−/− zebrafish larvae. Besides this, elmo1−/−, elmo2−/−, and elmo3−/− zebrafish exhibited several distinct changes in the vascular and glomerular structure and in the metabolome and the transcriptome. Especially, elmo3−/− zebrafish showed extensive differences in the larval transcriptome and an impaired survivability. Together, the data demonstrated that the three zebrafish Elmo proteins regulate not only similar but also divergent biological processes and mechanisms and show a low functional redundancy.

Comparative gene expression analysis of the engulfment and cell motility (ELMO) protein family in the mouse brain

Engulfment and cell motility (ELMO) proteins bind to Dock180, a guanine nucleotide exchange factor (GEF) of the Rac family, and regulate GEF activity. The resultant ELMO/Dock180/Rac module regulates cytoskeletal reorganization responsible for the engulfment of apoptotic cells, cell migration, and neurite extension. The expression and function of Elmo family proteins in the nervous system, however, are not yet fully understood. Here, we characterize the comparative gene expression profiles of three Elmo family members (Elmo1, Elmo2, and Elmo3) in the brain of C57BL/6J mice, a widely used inbred strain, together with reeler mutant mice to understand gene expression in normal laminated brain areas compared with abnormal areas. Although all three Elmo genes showed widespread mRNA expression over various mouse tissues tested, Elmo1 and Elmo2 were the major types expressed in the brain, and three Elmo genes were up-regulated between the first postnatal week (infant stage) and the third postnatal week (juvenile, weaning stage). In addition, the mRNAs of Elmo genes showed distinct distribution patterns in various brain areas and cell-types; such as neurons including inhibitory interneurons as well as some non-neuronal cells. In the cerebral cortex, the three Elmo genes were widely expressed over many cortical regions, but the predominant areas of Elmo1 and Elmo2 expression tended to be distributed unevenly in the deep (a lower part of the VI) and superficial (II/III) layers, respectively, which also changed depending on the cortical areas and postnatal stages. In the dentate gyrus of the hippocampus, Elmo2 was expressed in dentate granule cells more in the mature stage rather than the immature-differentiating stage. In the thalamus, Elmo1 but not the other members was highly expressed in many nuclei. In the medial habenula, Elmo2 and Elmo3 were expressed at intermediate levels. In the cerebellar cortex, Elmo1 and Elmo2 were expressed in differentiating-mature granule cells and mature granule cells, respectively. In the Purkinje cell layer, Elmo1 and Elmo2 were expressed in Purkinje cells and Bergmann glia, respectively. Disturbed cellular distributions and laminar structures caused by the reeler mutation did not severely change expression in these cell types despite the disturbed cellular distributions and laminar structures, including those of the cerebrum, hippocampus, and cerebellum. Taken together, these results suggested that these three Elmo family members share their functional roles in various brain regions during prenatal-postnatal development.

CCT α is a novel biomarker for diagnosis of laryngeal squamous cell cancer

Choline phosphate-based delivery systems can target the acidic tumor microenvironment. In this study, we set out to evaluate the diagnostic value of Choline phosphate cytidylyltransferase-α (CCTα) in laryngeal squamous cell cancer (LSCC). The expression of CCTα was detected using immunohistochemistry in 50 LSCC patients’ tissues and 16 vocal polyps as control group. Then, clinical data was collected and we used receiver operating characteristic curve (ROC) to estimate the potential of CCTα as diagnostic biomarker. We found CCTα levels to be significantly high in the tissues derived from LSCC patients, (p < 0.001). Further, we observed a positive correlation of CCTα with tumor size (p < 0.001), TNM stage (p < 0.001), lymph node metastasis (p < 0.001) as well as the grade of LSCC malignancy (p < 0.001). Furthermore, AUC was determined to be 0.939 by ROC, and the optimal cutoff value 3.100, with 76.0% sensitivity and 100% specificity. We also found an epigenetic basis of CCTα over-expression in LSCC tissues with significantly reduced methylation of CCTα in LSCC tissues, compared to vocal polyps (p < 0.001). These results support epigenetically-induced over-expression of CCTα as a potential diagnostic marker for LSCC.

Down Regulation of the Expression of ELMO3 by COX2 Inhibitor Suppresses Tumor Growth and Metastasis in Non-Small-Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is one of the most common malignancies. Studies have shown that engulfment and cell motility 3 (ELMO3) is highly expressed in NSCLC and can be used as a novel biomarker, but its underlying mechanism remains to be explored. The aim of this study was to investigate the mechanism by which ELMO3 may be down-regulated by COX-2 inhibitors to inhibit NSCLC. NSCLC tissue and adjacent normal lung tissue from 24 patients were used to detect the mRNA and protein expression of ELMO3, COX-2, and other related proteins by Western blot, RT-PCR, and Immunohistochemical analysis. Lewis Lung carcinoma (LLC) cells were used to investigate the effects and the mechanism of siELMO3 and COX-2 inhibitor. C57BL/6 mice inoculated with LLC cells by subcutaneous (s.c.) injection were used to detect the in vivo effects of cox-2 inhibitor. The expression of ELMO3 and cyclooxygenase-2 (COX-2) in human NSCLC tissues was significantly increased compared with that in the adjacent normal tissues. ELMO3 exhibited a positive correlation with COX-2 expression. Moreover, knockdown of ELMO3 suppressed the epithelial-mesenchymal transition (EMT), adhesion, and metastasis of Lewis lung carcinoma (LLC) cells. Importantly, Parecoxib, a selective inhibitor of COX-2, significantly reduced the expression of ELMO3 and EMT in LLC cells and LLC-bearing mice. Furthermore, it could inhibit the growth, adhesion and metastasis of LLC cells in vitro. Our results demonstrate that down regulation of ELMO3 suppressed growth and metastasis of lung cancer by inhibiting EMT. Parecoxib could reduce ELMO3 expression and suppress growth and metastasis of lung cancer, which might be a useful chemotherapeutic agent for inhibiting metastasis and recurrence of NSCLC.

ELMO3 - a Negative Prognostic Marker in Minor Salivary Gland Carcinoma

Engulfment and cell motility 3 protein (ELMO3) is a protein that is involved in cell migration and promotes the remodeling of the cytoskeleton. Moreover, it is described as a prognostic marker in several cancers. The aim of this study was to evaluate ELMO3 expression in patients with minor salivary gland carcinoma. The expression of ELMO3 was examined by immunohistochemistry. The intensity of staining was evaluated and data was correlated to clinical outcome. Forty-six patients with complete clinical data were included into statistical analysis. ELMO3 expression was observed in 85% of the cases. High staining intensity of ELMO3 correlated with a significantly worse disease free survival (p = .0495) and a higher recurrence rate (p = .0071). In conclusion, it is still difficult to predict the clinical outcome of patients with minor salivary gland carcinoma. Evaluation of ELMO3 might serve as a clinical prognostic marker in future.

Silencing ELMO3 Inhibits the Growth, Invasion, and Metastasis of Gastric Cancer

ELMO3 is a member of the engulfment and cell motility (ELMO) protein family, which plays a vital role in the process of chemotaxis and metastasis of tumor cells. However, remarkably little is known about the role of ELMO3 in cancer. The present study was conducted to investigate the function and role of ELMO3 in gastric cancer (GC) progression. The expression level of ELMO3 in gastric cancer tissues and cell lines was measured by means of real-time quantitative PCR (qPCR) and Western blot analysis. RNA interference was used to inhibit ELMO3 expression in gastric cancer cells. Then, wound-healing assays, Transwell assays, MTS assays, flow cytometry, and fluorescence microscopy were applied to detect cancer cell migration, cell invasion, cell proliferation, the cell cycle, and F-actin polymerization, respectively. The results revealed that ELMO3 expression in GC tumor tissues was significantly higher than in the paired adjacent tissues. Moreover, knockdown of ELMO3 by a specific siRNA significantly inhibited the processes of cell proliferation, invasion, metastasis, regulation of the cell cycle, and F-actin polymerization. Collectively, the results indicate that ELMO3 participates in the processes of cell growth, invasion, and migration, and ELMO3 is expected to be a potential diagnostic and prognostic marker for GC.

DNA Methylation Levels of the ELMO Gene Promoter CpG Islands in Human Glioblastomas

Complete surgical resection of glioblastoma is difficult due to the invasive nature of this primary brain tumor, for which the molecular mechanisms behind remain poorly understood. The three human ELMO genes play key roles in cellular motility, and have been linked to metastasis and poor prognosis in other cancer types. The aim of this study was to investigate methylation levels of the ELMO genes and their correlation to clinical characteristics and outcome in patients diagnosed with glioblastoma. To measure DNA methylation levels we designed pyrosequencing assays targeting the promoter CpG island of each the ELMO genes. These were applied to diagnostic tumor specimens from a well-characterized cohort of 121 patients who received standard treatment consisting of surgery, radiation therapy, plus concomitant and adjuvant chemotherapy. The promoter methylation levels of ELMO1 and ELMO2 were generally low, whereas ELMO3 methylation levels were high, in the tumor biopsies. Thirteen, six, and 18 biopsies were defined as aberrantly methylated for ELMO1, ELMO2, and ELMO3, respectively. There were no significant associations between the methylation status of any of the ELMO gene promoter CpG islands and overall survival, progression-free survival, and clinical characteristics of the patients including intracranial tumor location. Therefore, the methylation status of the ELMO gene promoter CpG islands is unlikely to have prognostic value in glioblastoma.