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Chemokines orchestrate many aspects of tumorigenic processes such as angiogenesis, apoptosis and metastatic spread, and related receptors are expressed on tumor cells as well as on inflammatory cells (e.g., tumor-infiltrating T cells, TILs) in the tumor microenvironment. Expressional changes of chemokines and their receptors in solid cancers are common and well known, especially in affecting colorectal cancer patient outcomes. Therefore, the aim of this current systematic review and meta-analysis was to classify chemokines as a prognostic biomarker in colorectal cancer patients. A systematic literature search was conducted in PubMed, CENTRAL and Web of Science. Information on the chemokine expression of 25 chemokines in colorectal cancer tissue and survival data of the patients were investigated. The hazard ratio of overall survival and disease-free survival with chemokine expression was examined. The risk of bias was analyzed using Quality in Prognosis Studies. Random effects meta-analysis was performed to determine the impact on overall respectively disease survival. For this purpose, the pooled hazard ratios (HR) and their 95% confidence intervals (CI) were used for calculation. Twenty-five chemokines were included, and the search revealed 5556 publications. A total of thirty-one publications were included in this systematic review and meta-analysis. Overexpression of chemokine receptor CXCR4 was associated with both a significantly reduced overall survival (HR = 2.70, 95%-CI: 1.57 to 4.66, p = 0.0003) as well as disease-free survival (HR = 2.68, 95%-CI: 1.41 to 5.08, p = 0.0026). All other chemokines showed either heterogeneous results or few studies were available. The overall risk of bias for CXCR4 was rated low. At the current level of evidence, this study demonstrates that CXCR4 overexpression in patients with colorectal cancer is associated with a significantly diminished overall as well as disease-free survival. Summed up, this systematic review and meta-analysis reveals CXCR4 as a promising prognostic biomarker. Nevertheless, more evidence is needed to evaluate CXCR4 and its antagonists serving as new therapeutic targets. [ABSTRACT FROM AUTHOR]

S100A11 is a small Ca2+-activatable protein known to localize along stress fibers (SFs). Analyzing S100A11 localization in HeLa and U2OS cells further revealed S100A11 enrichment at focal adhesions (FAs). Strikingly, S100A11 levels at FAs increased sharply, yet transiently, just before FA disassembly. Elevating intracellular Ca2+ levels with ionomycin stimulated both S100A11 recruitment and subsequent FA disassembly. However, pre-incubation with the nonmuscle myosin II (NMII) inhibitor blebbistatin or with an inhibitor of the stretch-activatable Ca2+ channel Piezo1 suppressed S100A11 recruitment, implicating S100A11 in an actomyosin-driven FA recruitment mechanism involving Piezo1-dependent Ca2+ influx. Applying external forces on peripheral FAs likewise recruited S100A11 to FAs even if NMII activity was inhibited, corroborating the mechanosensitive recruitment mechanism of S100A11. However, extracellular Ca2+ and Piezo1 function were indispensable, indicating that NMII contraction forces act upstream of Piezo1-mediated Ca2+ influx, in turn leading to S100A11 activation and FA recruitment. S100A11-knockout cells display enlarged FAs and had delayed FA disassembly during cell membrane retraction, consistent with impaired FA turnover in these cells. Our results thus demonstrate a novel function for S100A11 in promoting actomyosin contractility-driven FA disassembly. [ABSTRACT FROM AUTHOR]

Background: Liver metastases severely reduce the long term survival of colorectal cancer patients. Long non-coding RNAs (lncRNAs) CCAT1 and CCAT2 have previously been found to be associated with impaired patient outcomes in primary colorectal cancer. We aimed to elucidate the role of CCAT1 and CCAT2 in colorectal liver metastases. Methods: Total RNA was isolated from 97 human tissue samples of colorectal liver metastases and adjacent normal liver tissue. Gene expression analysis was performed by RT-qPCR and Multiplex ELISA and correlated with patient characteristics and survival. Gene expression, cancer cell migration, invasion, and proliferation were studied after siRNA-mediated knockdown of CCAT1, CCAT2, and MYC in metastatic colorectal cancer cell lines Colo205 and HROC277Met2. Results: Elevated expression levels of lncRNAs CCAT1 and CCAT2, and their common target MYC in colorectal liver metastases were associated with prolonged progression-free survival after liver resection. High expression of CCAT1 was likewise associated with prolonged overall survival. Knockdown of CCAT1, CCAT2, and MYC resulted in increased migratory and invasive potential in metastatic colorectal cancer cell lines. Gene expression analysis revealed alterations in constituents of Wnt signaling following knockdown. Conclusion: Our findings demonstrate tumor-suppressive functions of lncRNAs CCAT1 and CCAT2 in colorectal liver metastases. They suppress Wnt signaling directly and indirectly through target gene MYC and might prevent further metastatic spread from colorectal liver metastases. [ABSTRACT FROM AUTHOR]

A protocol combining immobilized metal ion affinity chromatography and [beta]-elimination with concurrent Michael addition has been developed for enhanced analysis of protein phosphorylation. Immobilized metal ion affinity chromatography was initially used to enrich for phosphorylated peptides. [beta]-Elimination, with or without concurrent Michael addition, was then subsequently used to simultaneously elute and derivatize phosphopeptides bound to the chromatography resin. Derivatization of the phosphate facilitated the precise determination of phosphorylation sites by MALDI-PSD/LIFT tandem mass spectrometry, avoiding complications due to ion suppression and phosphate lability in mass spectrometric analysis of phosphopeptides. Complementary use of immobilized metal ion affinity chromatography and [beta]-elimination with concurrent Michael addition in this manner circumvented several inherent disadvantages of the individual methods. In particular, (i) the protocol discriminated O-linked glycosylated peptides from phosphopeptides prior to [beta]-elimination/Michael addition and (ii) the elution of peptides from the chromatography resin as derivatized phosphopeptides distinguished them from unphosphorylated species that were also retained. The chemical derivatization of phosphopeptides greatly increased the information obtained during peptide sequencing by mass spectrometry. The combined protocol enabled the detection and sequencing of phosphopeptides from protein digests at low femtomole concentrations of initial sample and was employed to identify novel phosphorylation sites on the cell adhesion protein p120 catenin and the glycoprotein fetuin.