Paired-related homeobox 1 induces epithelial-mesenchymal transition in oesophageal squamous cancer.

BACKGROUND: It is unclear that paired-related homeobox 1 (PRRX1) induces epithelial-mesenchymal transition (EMT) in oesophageal cancer and the specific function of PRRX1 in oesophageal cancer metastasis. AIM: To assess the significance of PRRX1 expression and investigate the mechanism of EMT in oesophageal cancer metastasis. METHODS: Detect the expression of PRRX1 by immunohistochemistry in oesophageal tumour tissues and adjacent normal oesophageal tissues; the PRRX1 short hairpin RNA (shRNA) or blank vector lentiviral gene delivery system was transfected into cells; cell proliferation assay, soft agar colony formation assays, cell invasion and migration assays and animal studies were used to observe cells biological characteristics In vitro and in vivo; XAV939 and LiCl were used to alter the activity of Wnt/ß-catenin pathway. Immunofluorescence staining and western blot analysis were used to detect protein expression of EMT markers and Wnt/ß-catenin pathway. RESULTS: PRRX1 is expressed at high levels in oesophageal cancer specimens and is closely related to tumour metastasis in patients with oesophageal cancer. Regulation of PRRX1 expression might exert obvious effects on cell proliferation, especially the migration and invasion of oesophageal cancer cells. Moreover, silencing PRRX1 expression using a shRNA produced the opposite effects. In addition, when PRRX1 was overexpressed, inhibition of the Wnt/ß-catenin pathway with XAV939 negated the effect of PRRX1 on EMT, whereas when PRRX1 was downregulated, activation of the Wnt/ß-catenin pathway with LiCl impaired the effect on EMT. CONCLUSION: PRRX1 is upregulated in oesophageal cancer is closely correlated with cancer metastasis. Additionally, PRRX1 induces EMT in oesophageal cancer metastasis through activation of Wnt/ß-catenin signalling.

Clinical significance of serum S100A10 in lung cancer.

OBJECTIVE: To investigate the clinical significance of serum S100 calcium-binding protein A10 (S100A10) levels in lung cancer. METHODS: This prospective study enrolled patients with lung cancer, patients with benign lung nodules and healthy control subjects. Serum S100A10 levels and three biomarkers were measured and compared between the groups. Associations between serum S100A10 and clinical characteristics in patients with lung cancer were investigated. The diagnostic efficacy of serum S100A10 and carcinoembryonic antigen for lung cancer was calculated. RESULTS: The study enrolled 82 patients with lung cancer, 21 with benign lung nodules and 50 healthy controls. Serum S100A10 levels were significantly higher in patients with lung cancer compared with patients with benign lung nodules and healthy control subjects. Serum S100A10 levels of patients with advanced lung cancer were significantly higher than those with early stage disease. Patients with lymph node metastases had significantly higher serum S100A10 levels than patients without lymph node metastases. The cut-off serum S100A10 value for lung cancer detection was 1.34 ng/ml, which had a sensitivity of 48.2%, a specificity of 76.2% and an area under the curve of 0.63. CONCLUSION: Serum S100A10 was significantly correlated with disease stage and lymph node metastasis. It has the potential to be a tumour biomarker for lung cancer.

Sestrin 2 suppresses cells proliferation through AMPK/mTORC1 pathway activation in colorectal cancer.

Sestrin 2 is a conserved antioxidant protein that reduces reactive oxygen species (ROS) and inhibits mammalian target of rapamycin complex 1 (mTORC1). We previously showed that sestrin 2 is abnormally decreased in colorectal cancer (CRC). To elucidate the molecular mechanism behind the potential contribution of sestrin 2 to CRC, we used a lentiviral expression vector system to determine the effects of sestrin 2 overexpression on human CRC cells. We found that sestrin 2 overexpression decreased ROS production, inhibited cell growth, and stimulated apoptosis in two CRC cell lines. In parallel, expression of the proliferation marker PCNA was decreased, proapoptotic caspase 3, 7, and 9 levels were increased, and expression of the anti-apoptotic protein survivin was reduced. Sestrin 2 overexpression also activated the adenosine monophosphate-activated protein kinase (AMPK) pathway, and suppressed mTORC1 signaling. Treating CRC cells with compound C, an AMPK inhibitor, reversed or attenuated changes in proliferation, apoptosis, and signaling proteins of the AMPK/mTORC1 axis. In a xenograft mouse model, CRC growth was attenuated by sestrin 2 overexpression. These results suggest that sestrin 2 suppresses CRC cell growth through activation of the AMPK/mTORC1 pathway and induction of apoptosis, and could be a novel pharmacological target for the treatment of CRC.

Decreased expression of sestrin 2 predicts unfavorable outcome in colorectal cancer.

Sestrin 2 is a conserved antioxidant protein that is involved in p53­dependent antioxidant defenses and protects cells against oxidative stresses. The present study was conducted to examine the expression of sestrin 2 in colorectal cancer (CRC) and investigate a possible relationship between sestrin 2 expression and prognosis in CRC. The expression of sestrin 2 in human CRC tissues and cell lines was evaluated by immunohistochemical or immunofluorescent staining and western blot analysis. The correlations between sestrin 2 expression in human CRC tissues and clinicopathological variables, including overall survival (OS) and disease­free survival (DFS), were analyzed. Both human CRC tissues and cell lines showed a decreased expression of sestrin 2. Furthermore, a low expression of sestrin 2 was significantly correlated with advanced tumor stage, lymphatic invasion, lymph node metastasis, vascular invasion and liver metastasis. Survival analysis showed that patients with low sestrin 2 staining had a significantly worse DFS and OS. Additionally, early or advanced stage CRC patients with a low expression of sestrin 2 had a shorter survival. In univariate analysis, the patients with low sestrin 2 expression, advanced tumor stage, lymphatic invasion, lymphatic node metastasis, vascular invasion, liver metastasis and peritoneal metastasis had shorter OS and DFS. In multivariate analysis, only low sestrin 2 expression, advanced tumor stage, lymphatic node metastasis, vascular invasion and liver metastasis remained as independent prognostic factors of poor OS and DFS. The findings suggested that a decreased expression of sestrin 2 is associated with an unfavorable prognosis, which suggests that it is a novel and crucial predictor for CRC metastasis.

High expression of CASK correlates with progression and poor prognosis of colorectal cancer.

Calcium/calmodulin-dependent serine protein kinase (CASK), which localizes at cell-cell adhesion sites and binds to the heparan sulfate proteoglycan syndecan-2, is involved in cell proliferation, cytoskeletal remodeling, and cell migration. To demonstrate the role of CASK in colorectal cancer (CRC) carcinogenesis, we examined the expression of CASK and its binding protein syndecan-2 in human CRC tissues. The expression of CASK was measured in CRC specimens and the controls from adenomas and normal mucosae by immunohistochemical staining and Western blot analysis. Syndecan-2 protein level was tested in CRC samples and the controls by Western blot analysis. The correlations between CASK expression and clinicopathological variables, including disease-free survival (DFS) and overall survival (OS), were analyzed. Compared to the controls, both CASK and syndecan-2 expression were enhanced in CRC tissues. Furthermore, high expression of CASK and syndecan-2 was significantly correlated with advanced tumor stage, lymphatic invasion, lymph node metastasis, vascular invasion, liver metastasis, and unresectable metastatic CRC. Survival analysis showed that patients with low CASK staining had a significantly better survival compared to patients with high CASK staining. In multivariate analysis, CASK overexpression, advanced tumor stage, lymph node metastasis, vasvular invasion, and liver metastasis were independent prognostic factors of poor DFS and OS. Our present study indicates that CASK overexpression is associated with an unfavorable prognosis. CASK is an independent prognostic factor for CRC, which suggests that it is a novel and crucial predictor for CRC metastasis.

2-Bromo-4-chloro-6-[(E)-o-tolyl-imino-meth-yl]phenol.

The title compound, C(14)H(11)BrClNO, is a Schiff base compound derived from the condensation of 3-bromo-5-chloro-salicyl-aldehyde and o-toluidine in methanol. The aromatic rings make a dihedral angle of 38.3 (1)°. The mol-ecular conformation is stabilized by an intra-molecular O-H⋯N hydrogen bond, generating an S(6) ring.

[Study on the interaction of hesperidin or icariin with lysozyme by fluorescence spectroscopy].

The interaction of hesperidin (HES) or icariin (ICA) and lysozyme (LYS) was studied by fluorescence spectroscopy in physiological buffer solution. It was observed that there was a strong fluorescence quenching effect of hesperidin or icariin on lysozyme. The quenching constants of the drugs with lysozyme were measured at different temperatures, and the quenching mechanism was suggested as dynamic quenching for HES-LYS system and both static and dynamic quenching for ICA-LYS system. The thermodynamic parameters of the interaction of hesperidin or icariin and lysozyme were measured according to the Van's Hoff equation: the enthalpy change (DeltaH) and the entropy change (DeltaS) of HES-LYS system and ICA-LYS system were calculated to be 20.29 kJ x mol(-1) and 146.28 J x mol(-1) x K(-1), and -3.47 kJ x mol(-1) and 81.16 J x mol(-1) x K(-1), respectively, which indicated that the interaction of hesperidin and lysozyme was driven mainly by hydrophobic force, whereas the interaction of icariin and lysozyme was driven mainly by electrostatic force. It was showed that the reaCtion processes of the two systems occurred spontaneously since Gibbs free energy change (DeltaG) values were negative. The binding distances of hesperidin and icariin from the lysozyme tryptophan residue were calculated to be 1.34 nm and 1.24 nm, respectively, based on the Förster's theory of non-radiation energy transfer. The results of synchronous fluorescence spectra showed that the binding of hesperidin or icariin to lysozyme induced conformational changes in lysozyme.