Significance of PYK2 level as a prognosis predictor in patients with colon adenocarcinoma after surgical resection

PF-431396 hydrate inhibition of kinase phosphorylation during adherent-invasive Escherichia coli infection inhibits intra-macrophage replication and inflammatory cytokine release

Adherent-invasive Escherichia coli (AIEC) have been implicated in the aetiology of Crohn's disease (CD). They are characterized by an ability to adhere to and invade intestinal epithelial cells, and to replicate intracellularly in macrophages resulting in inflammation. Proline-rich tyrosine kinase 2 (PYK2) has previously been identified as a risk locus for inflammatory bowel disease and a regulator of intestinal inflammation. It is overexpressed in patients with colorectal cancer, a major long-term complication of CD. Here we show that Pyk2 levels are significantly increased during AIEC infection of murine macrophages while the inhibitor PF-431396 hydrate, which blocks Pyk2 activation, significantly decreased intramacrophage AIEC numbers. Imaging flow cytometry indicated that Pyk2 inhibition blocked intramacrophage replication of AIEC with no change in the overall number of infected cells, but a significant reduction in bacterial burden per cell. This reduction in intracellular bacteria resulted in a 20-fold decrease in tumour necrosis factor α secretion by cells post-AIEC infection. These data demonstrate a key role for Pyk2 in modulating AIEC intracellular replication and associated inflammation and may provide a new avenue for future therapeutic intervention in CD.

Computational Design of Peptides with Improved Recognition of the Focal Adhesion Kinase FAT Domain

We describe a two-stage computational protein design (CPD) methodology for the design of peptides binding to the FAT domain of the protein focal adhesion kinase. The first stage involves high-throughput CPD calculations with the Proteus software. The energies of the folded state are described by a physics-based energy function and of the unfolded peptides by a knowledge-based model that reproduces aminoacid compositions consistent with a helicity scale. The obtained sequences are filtered in terms of the affinity and the stability of the complex. In the second stage, design sequences are further evaluated by all-atom molecular dynamics simulations and binding free energy calculations with a molecular mechanics/implicit solvent free energy function.

RB1CC1 functions as a tumor-suppressing gene in renal cell carcinoma via suppression of PYK2 activity and disruption of TAZ-mediated PDL1 transcription activation

Rb1-inducible coiled-coil 1 (RB1CC1) has been demonstrated to function as an inhibitor of proline-rich/Ca-activated tyrosine kinase 2 (PYK2) by binding to the kinase domain of PYK2, which promotes the proliferation, invasion, and migration of renal cell carcinoma (RCC) cells. Additionally, in breast cancer, PYK2 positively regulates the expression of transcriptional co-activator with PDZ-binding motif (TAZ) which in turn can enhance PDL1 levels in breast and lung cancer cells. The current study was performed to decipher the impact of RB1CC1 in the progression of RCC via regulation of the PYK2/TAZ/PDL1 signaling axis. Expression of RB1CC1 and PYK2 was quantified in clinical tissue samples from RCC patients. The relationship between TAZ and PYK2, TAZ and PDL1 was then validated. The cellular processes of doxorubicin (DOX)-induced human RCC cell lines including the abilities of proliferation, colony formation, sphere formation and apoptosis, as well as the tumorigenicity of transfected cells, were evaluated after the alteration of RB1CC1 expression. RB1CC1 exhibited decreased expression in RCC tissues and was positively correlated with patient survival. RB1CC1 could inhibit the activity of PYK2, which in turn stimulated the stability of TAZ protein by phosphorylating TAZ. Meanwhile, TAZ protein activated PDL1 transcription by binding to the promoter region of PDL1. RB1CC1 overexpression or PYK2 knockdown could help everolimus (EVE) to inhibit tumor proliferation and activate immune response. Taken together, RB1CC1 can potentially augment the response of RCC cells to immunotherapy by suppressing the PYK2/TAZ/PDL1 signaling axis.

MET-Pyk2 Axis Mediates Acquired Resistance to FGFR Inhibition in Cancer Cells

Deregulation of fibroblast growth factor receptors (FGFRs) signaling, as a result of FGFR amplification, chromosomal translocation, or mutations, is involved in both initiation and progression of a wide range of human cancers. Clinical data demonstrating the dependence of cancer cells on FGFRs signaling clearly indicate these receptors as the molecular targets of anti-cancer therapies. Despite the increasing number of tyrosine kinase inhibitors (TKIs) being investigated in clinical trials, acquired resistance to these drugs poses a serious therapeutic problem. In this study, we focused on a novel pan-FGFR inhibitor-CPL304110, currently being investigated in phase I clinical trials in adults with advanced solid malignancies. We analyzed the sensitivity of 17 cell lines derived from cancers with aberrant FGFR signaling, i.e. non-small cell lung cancer, gastric and bladder cancer to CPL304110. In order to explore the mechanism of acquired resistance to this FGFR inhibitor, we developed from sensitive cell lines their variants resistant to CPL304110. Herein, for the first time we revealed that the process of acquired resistance to the novel FGFR inhibitor was associated with increased expression of MET in lung, gastric, and bladder cancer cells. Overexpression of MET in NCI-H1703, SNU-16, RT-112 cells as well as treatment with HGF resulted in the impaired response to inhibition of FGFR activity. Moreover, we demonstrated that cells with acquired resistance to FGFR inhibitor as well as cells overexpressing MET displayed enhanced migratory abilities what was accompanied with increased levels of Pyk2 expression. Importantly, inhibition of both MET and Pyk2 activity restored sensitivity to FGFR inhibition in these cells. Our results demonstrate that the HGF/MET-Pyk2 signaling axis confers resistance to the novel FGFR inhibitor, and this mechanism is common for lung, gastric, and bladder cancer cells. Our study suggests that targeting of MET/Pyk2 could be an approach to overcome resistance to FGFR inhibition.

Recognition of LD motifs by the focal adhesion targeting domains of focal adhesion kinase and proline-rich tyrosine kinase 2-beta: Insights from molecular dynamics simulations

The focal adhesion kinase (FAK) and the proline-rich tyrosine kinase 2-beta (PYK2) are implicated in cancer progression and metastasis and represent promising biomarkers and targets for cancer therapy. FAK and PYK2 are recruited to focal adhesions (FAs) via interactions between their FA targeting (FAT) domains and conserved segments (LD motifs) on the proteins Paxillin, Leupaxin, and Hic-5. A promising new approach for the inhibition of FAK and PYK2 targets interactions of the FAK domains with proteins that promote localization at FAs. Advances toward this goal include the development of surface plasmon resonance, heteronuclear single quantum coherence nuclear magnetic resonance (HSQC-NMR) and fluorescence polarization assays for the identification of fragments or compounds interfering with the FAK-Paxillin interaction. We have recently validated this strategy, showing that Paxillin mimicking polypeptides with 2 to 3 LD motifs displace FAK from FAs and block kinase-dependent and independent functions of FAK, including downstream integrin signaling and FA localization of the protein p130Cas. In the present work we study by all-atom molecular dynamics simulations the recognition of peptides with the Paxillin and Leupaxin LD motifs by the FAK-FAT and PYK2-FAT domains. Our simulations and free-energy analysis interpret experimental data on binding of Paxillin and Leupaxin LD motifs at FAK-FAT and PYK2-FAT binding sites, and assess the roles of consensus LD regions and flanking residues. Our results can assist in the design of effective inhibitory peptides of the FAK-FAT: Paxillin and PYK2-FAT:Leupaxin complexes and the construction of pharmacophore models for the discovery of potential small-molecule inhibitors of the FAK-FAT and PYK2-FAT focal adhesion based functions.

The YTH Domain Family of N6-Methyladenosine "Readers" in the Diagnosis and Prognosis of Colonic Adenocarcinoma

To profile the landscape of methylation N⁶ adenosine (m⁶A) RNA regulators in colonic adenocarcinoma (COAD) and to explore potential diagnostic and prognostic biomarkers, we assessed the differential expression patterns of m⁶A RNA methylation regulators between 418 COAD patients and 41 controls based on profiling from The Cancer Genome Atlas (TCGA) database. We plotted the receiver operating characteristic (ROC) curves and calculated the area under the curve (AUC) values to estimate the discrimination ability. The relationship between the expression of m⁶A RNA methylation regulators and clinicopathological characteristics was explored. Kaplan-Meier plotter, log-rank test, and Cox regression were used and a nomogram was created to explore the prognostic significance of m⁶A-related genes in overall survival at the mRNA level. Pathway analysis was performed by gene set enrichment analysis (GSEA) using TCGA dataset, and a coexpression network was built based on the STRING database. We observed that YTHDF1, METTL3, and KIAA1429 were significantly upregulated, while YTHDF3, YTHDC2, METTL14, and ALKBH5 were significantly downregulated in COAD samples compared to normal samples. YTHDF1 had the highest diagnostic value. Low expression of YTHDF3 predicted a poor survival rate in COAD patients. YTHDC2 was related to sex and showed a downward trend as clinical stage increased. Our results indicate that the YT521-B homology (YTH) domain family (“readers”), especially YTHDF1, YTHDF3, and YTHDC2, might play a significant role in the detection, progression, and prognosis of COAD, indicating that they are promising cancer biomarkers.

Glycerophosphodiester phosphodiesterase 1 (GDE1) acts as a potential tumor suppressor and is a novel therapeutic target for non-mucin-producing colon adenocarcinoma

Colon adenocarcinoma (COAD) represents a major public health issue due to its high incidence and mortality. As different histological subtypes of COAD are related to various survival outcomes and different therapies, finding specific targets and treatments for different subtypes is one of the major demands of individual disease therapy. Interestingly, as these different subtypes show distinct metabolic profiles, it may be possible to find specific targets related to histological typing by targeting COAD metabolism. In this study, the differential expression patterns of metabolism-related genes between COAD (n = 289) and adjacent normal tissue (n = 41) were analyzed by one-way ANOVA. We then used weighted gene co-expression network analysis (WGCNA) to further identify metabolism-related gene connections. To determine the critical genes related to COAD metabolism, we obtained 2,114 significantly differentially expressed genes (DEGs) and 12 modules. Among them, we found the hub module to be significantly associated with histological typing, including non-mucin-producing colon adenocarcinoma and mucin-producing colon adenocarcinoma. Combining survival analysis, we identified glycerophosphodiester phosphodiesterase 1 (GDE1) as the most significant gene associated with histological typing and prognosis. This gene displayed significantly lower expression in COAD compared with normal tissues and was significantly correlated with the prognosis of non-mucin-producing colon adenocarcinoma (p = 0.0017). Taken together, our study showed that GDE1 exhibits considerable potential as a novel therapeutic target for non-mucin-producing colon adenocarcinoma.

CDHR5 inhibits proliferation of hepatocellular carcinoma and predicts clinical prognosis

BACKGROUND

As one of the most prevalent malignancies, hepatocellular carcinoma (HCC) ranks the third leading cause of cancer death worldwide. Due to the lack of biomarkers for early diagnosis, the clinical outcome of HCC remains unsatisfied with the current common therapeutic approaches, including surgery and chemotherapies. Thus, sensitive biomarkers and targeted therapies are in great need.

AIMS

In this study, we explored and verified whether CDHR5 (cadherin-related family member 5), a cadherin family protein, could serve as the potential biomarkers for HCC in the clinic.

METHODS

A retrospective study which contained 154 HCC patients was performed. Chi-square was utilized to analyze the relationship between CDHR5 expression and the clinicopathological features of HCC patients. The Kaplan-Meier method and Cox regression analyses were then used to evaluate the survival of HCC patients. In addition, cell proliferation assay and colony formation assay were performed to examine the effects of CDHR5 on the progression of HepG2 and Huh7 cells.

RESULTS

IHC and RT-qPCR revealed that CDHR5 was downregulated in HCC tissues compared with adjacent liver tissues. In addition, CDHR5 expression was significantly correlated with tumor numbers, tumor size, and TNM stage. CDHR5 expression was then shown to be an independent risk factor for survival of HCC patients by survival analysis. In vitro experiments showed that CDHR5 suppressed the proliferation capacity of HCC cells.

CONCLUSIONS

Taken together, our study not only identified CDHR5 as a novel prognostic biomarker in HCC but also provided evidence that CDHR5 can inhibit HCC cell proliferation.