Phosphatase and Tensin Homolog (PTEN) Represses Colon Cancer Progression through Inhibiting Paxillin Transcription via PI3K/AKT/NF-κB Pathway.

The tumor suppressor gene phosphatase and tensin homolog (PTEN) is frequently mutated in colon cancer. However, the potential contribution of loss of PTEN to colon cancer progression remains unclear. In this study, we demonstrated that PTEN overexpression or knockdown in Lovo colon cancer cells decreased or increased paxillin expression, respectively. Moreover, paxillin reversed PTEN-mediated inhibition of Lovo cell invasion and migration. Overexpression of PTEN in an orthotropic colon cancer nude mice model inhibited tumor formation and progression. In addition, PTEN protein level was negatively correlated with that of paxillin in human colon cancer tissues. Mechanistically, we identified three NF-κB binding sites on paxillin promoter and confirmed that paxillin was a direct transcriptional target of NF-κB. Our findings reveal a novel mechanism by which PTEN inhibits the progression of colon cancer by inhibiting paxillin expression downstream of PI3K/AKT/NF-κB pathway. Thereby, PTEN/PI3K/AKT/NF-κB/paxillin signaling cascade is an attractive therapeutic target for colon cancer progression.

Low microRNA150 expression is associated with activated carcinogenic pathways and a poor prognosis in patients with breast cancer.

Breast cancer is the most common type of cancer amongst women worldwide, and numerous microRNAs (miRNAs/miRs) are involved in the initiation and progression of breast cancer. The aim of the present study was to identify hub miRNAs and determine the underlying mechanisms regulated by these miRNAs in breast cancer. Breast invasive carcinoma transcriptome data (including mRNAs and miRNAs), and clinical data were acquired from The Cancer Genome Atlas database. Differential gene expression analysis, co­expression network analysis, gene set enrichment analysis (GSEA) and prognosis analysis were used to screen the hub miRNAs and explore their functions. Functional experiments were used to determine the underlying mechanisms of the hub miRNAs in breast cancer cells. The results revealed that low miR150 expression predicted a more advanced disease stage, and was associated with a less favorable prognosis. Through the combined use of five miRNA­target gene prediction tools, 31 potential miR150 target genes were identified. GSEA revealed that low miR150 expression was associated with the upregulation of several cancer­associated signaling pathways, and the downregulation of several tumor suppressor genes. Furthermore, miR150 independently affected overall survival in patients, and interacted with its target genes to indirectly affect overall and disease­free survival. Functional experiments demonstrated that miR150 positively regulated B and T lymphocyte attenuator (BTLA), and the downregulation of miR150 and BTLA combined promoted cell migration. In conclusion, the present study revealed that low miR150 expression was associated with less favorable clinical features, upregulation of several carcinogenic signaling pathways, and poor patient survival. Additionally, a miR150­BTLA axis was suggested to regulate cell viability and migration.

MFAP2 is overexpressed in gastric cancer and promotes motility via the MFAP2/integrin α5ß1/FAK/ERK pathway.

Gastric cancer (GC) is one of the most common malignancies and its prognosis is extremely poor. This study identifies a novel oncogene, microfibrillar-associated protein 2 (MFAP2) in GC. With integrative reanalysis of transcriptomic data, we found MFAP2 as a GC prognosis-related gene. And the aberrant expression of MFAP2 was explored in GC samples. Subsequent experiments indicated that silencing and exogenous MFAP2 could affect motility of cancer cells. The inhibition of silencing MFAP2 could be rescued by another FAK activator, fibronectin. This process is probably through affecting the activation of focal adhesion process via modulating ITGB1 and ITGA5. MFAP2 regulated integrin expression through ERK1/2 activation. Silencing MFAP2 by shRNA inhibited tumorigenicity and metastasis in nude mice. We also revealed that MFAP2 is a novel target of microRNA-29, and miR-29/MFAP2/integrin α5ß1/FAK/ERK1/2 could be an important oncogenic pathway in GC progression. In conclusion, our data identified MFAP2 as a novel oncogene in GC and revealed that miR-29/MFAP2/integrin α5ß1/FAK/ERK1/2 could be an important oncogenic pathway in GC progression.

Aberrant high expression level of MORC2 is a common character in multiple cancers.

Microrchidia 2 (MORC2) plays important roles in DNA damage repair and lipogenesis, but the clinical and functional role of MORC2 in cancer remains largely unexplored. In this study, we showed that MORC2 was widely expressed in human tissues while significantly up-regulated in most cancer types using immunohistochemical staining and analysis of messenger RNA expression profile of more than 2000 human tissue samples from 15 different organs (lung, prostate, liver, breast, brain, stomach, colon/rectum, pancreas, ovary, endometrium, skin, nasopharynx, kidney, esophagus, and bladder). We also found that the MORC2 expression level in high-grade cancer tissues was much more elevated and associated with unfavorable pathological characteristics, poor overall survival, and disease-free survival in several kinds of cancers such as non-small cell lung cancer and breast cancer. Gene set enrichment analysis was used to predict the genes modulated by MORC2, and the results showed that dysregulation of MORC2 in tumor may take part in the cell cycle regulation and genomic instability. We observed that MORC2 knockdown would arrest the cell cycle progress, and the genome of tumors with high MORC2 expression contained more point mutations and gene copy number variation, which validates our gene set enrichment analysis results. The results also showed that MORC2 knockdown would significantly inhibit the proliferation, colony forming, migration, and invasion in multiple cancer cell lines. Taken together, these results highlight the importance of MORC2 in tumorigenesis and cancer progression, and it may act as a potential diagnostic marker and therapeutic target for these diseases.

Evaluation of left ventricular myocardial mechanics by three-dimensional speckle tracking echocardiography in the patients with different graded coronary artery stenosis.

To investigate the relationship between left ventricular (LV) myocardial mechanics evaluated by three-dimensional speckle tracking echocardiography (3D-STE) and degree of coronary artery stenosis in patients with coronary artery disease (CAD). Ninety-seven suspected CAD patients without LV regional wall motion abnormality (RWMA) observed visually form traditional echocardiography were divided into four groups according to coronary artery angiography (CAG): 23 patients in slight stenosis group [stenosis rate (SR) ≤25%], 26 patients in mild stenosis group (25< SR ≤50%), 28 patients in moderate stenosis group (50< SR ≤75%), and 20 patients in severe stenosis group (SR >75%). Global longitudinal strain (GLS), circumferential strain (GCS), radial strain (GRS), area strain (AS) and three dimensional strain (3D-Strain) were obtained. The parameters from 3D-STE were compared between different groups and then the diagnostic value of global strains indicating different graded coronary artery stenosis was analyzed by the receiver operating characteristic curve. (1) There were significant difference in GLS, GCS, GRS, GAS and 3D-Strain between the severe stenosis group and any other group while all 3D-STE parameters except GCS in the moderate stenosis group were remarkably different from those respectively in mild group. (2) Receiver operator characteristic curve (ROC) analysis showed that the area under the curve of GLS, GRS, GCS, GAS, 3D-Strain were 0.899, 0.873, 0.723, 0.856 and 0.863 respectively for the identification of stenosis rate >50%, and 0.896, 0.866, 0.797, 0.909 and 0.899 respectively for the identification of severe stenosis. GAS less than -29.13% allowed a sensitivity of 95% and a specificity of 71.4%, while 3D strain less than 41.35% allowed a sensitivity of 90% and a specificity of 80.5% for evaluating serve coronary artery stenosis. The myocardial mechanics from 3D-STE in the CAD patients were characteristic. It could be expected to identify serve coronary stenosis with a good sensitivity and an acceptable specificity by using GAS or 3D-strain especially in the suspected CAD patients without RWMA on conventional echocardiography.