Toll-like receptor 6 inhibits colorectal cancer progression by suppressing NF-κB signaling.

Background: Toll-like receptors (TLRs) are implicated in the pathogenesis and progression of inflammation-associated cancers, except their role in regulating innate immunity. Specifically, a berrant expression of TLR6 has been observed in colorectal cancers (CRC). However, the effect of abnormal TLR6 expression on CRC remians unclear. Therefore, the present study evaluated TLR6 expression in CRC, its effect on CRC proliferation, and its underlying mechanism. Methods: The expression of TLR6 in CRC was assessed using data from TCGA, GTEx, and HPA datasets and immunohistochemical assays of tumor tissues from patients with CRC. In human CRC cell lines, TLR6 signaling was activated using the TLR6 agonist Pam2CSK4 and was blocked using antiTLR6-IgG; subsequently, cell growth, migration, invasion, cell cycle, and apoptosis were compared in CRC cells. The levels of the anti-apoptotic protein Bcl-2 and the apoptotic protein Bax were identified using western blotting. In addition, the effect of TLR6 knockdown by shRNAs in CRC cells was observed both in vitro and in vivo. Nuclear factor κB (NF-κB) level was evaluated using immunofluorescence and western bolt. Results: TLR6 expression was significantly downregulated in CRC tissues. The activation of TLR6 by Pam2CSK4 (100 pg/mL to 10 ng/mL) inhibited the proliferation of CRC cells. Compared with blocking TLR6 signaling using antiTLR6-IgG, activating TLR6 signaling significantly inhibited CRC cell growth, migration, and invasion as well as decreased the proportion of cells in the S and G2/M phases and promoted apoptosis. Furthermore, the knockdown of TLR6 by shRNA promoted the biological activity of CRC cells both in vitro and in vivo. Moreover, the activation of TLR6 signaling by Pam2CSK4 significantly downregulated NF-κB and Bcl-2 levels but upregulated Bax levels. Conclusion: The findings of this study demonstrate that TLR6 may play a inhibitive role in CRC tumorigenesis by suppressing the activity of NF-κB signaling.

Calprotectin and Neutrophil Gelatinase-Associated Lipocalin As Biomarkers of Acute Kidney Injury in Acute Coronary Syndrome.

BACKGROUND: Acute kidney injury (AKI) is increasingly being seen in patients with acute coronary syndromes (ACS) and it is associated with higher short-term and long-term morbidity and mortality. Therefore, it is of paramount importance to identify those ACS patients at risk for the development of AKI. The objective of this study was to evaluate two different plasma biomarkers calprotectin and neutrophil gelatinase-associated lipocalin (NGAL) in early detecting the development of AKI in ACS patients. METHODS: 172 ACS patients admitted to the Coronary Care Unit in Yantai Yuhuangding Hospital were prospectively enrolled. Their blood samples were obtained on admission and subjected to enzyme-linked immunosorbent assay to determine the levels of novel biomarkers. The clinical data and biomarkers were recorded and analyzed. RESULTS: In this study, 23 (13.4%) patients had a diagnosis of AKI. Statistical analysis demonstrated that in ACS patients with AKI, the following two biomarkers were significantly higher than these without AKI: plasma calprotectin (5942.26 ± 1955.88 ng/mL vs. 3210.29 ± 1833.60 ng/mL, p < 0.001) and plasma NGAL (164.91 ± 43.63 ng/mL vs. 122.48 ± 27.33 ng/mL, p < 0.001). Plasma calprotectin and NGAL could discriminate the development of AKI respectively with an area under the ROC curve (AUC) of 0.864 and 0.850. A combination of the two plasma biomarkers calprotectin and NGAL could early discriminate AKI in ACS patients with an AUC of 0.898. CONCLUSIONS: This study demonstrated a promising panel of plasma calprotectin and NGAL as early diagnostic biomarkers for AKI in ACS patients.

Ang-(1-7) inhibited mitochondrial fission in high-glucose-induced podocytes by upregulation of miR-30a and downregulation of Drp1 and p53.

BACKGROUND: The aim of this study was to investigate the possible effects of angiotensin-(1-7) [Ang-(1-7)] on podocytes and the mitochondrial signaling pathway in a high-glucose (HG) environment. METHODS: We established a model of HG-induced podocytes by incubating podocytes in RPMI 1640 containing 33mM glucose. The cells were divided into the following groups: (1) normal glucose group as control incubated in Roswell Park Memorial Institute (RPMI) 1640 containing 5mM glucose; (2) Ang-(1-7), 10nM, incubated in RPMI 1640 containing 5mM glucose; (3) the HG group incubated in RPMI 1640 containing 33mM glucose; and (4) Ang-(1-7), 10nM, incubated in HG group incubated in RPMI 1640 containing 33mM glucose. After a period of 24 hours, mitochondrial fission and podocyte fusion were observed by electron microscope. Additionally, p53 and Drp1 were tested by Western blot, the position of Drp1 was detected by immunofluorescence, and miR-30a was analyzed by quantitative real-time polymerase chain reaction. RESULTS: Ang-(1-7) inhibited mitochondrial fission in HG-treated podocytes. However, Ang-(1-7) also significantly reduced the expression of Drp1 and p53, and improved the expression of miR-30a in HG-induced podocytes. CONCLUSION: Ang-(1-7) inhibited mitochondrial fission in HG-induced podocytes by upregulation of miR-30a and downregulation of Drp1 and p53.