APC loss induces Warburg effect via increased PKM2 transcription in colorectal cancer.

BACKGROUND: Most cancer cells employ the Warburg effect to support anabolic growth and tumorigenesis. Here, we discovered a key link between Warburg effect and aberrantly activated Wnt/ß-catenin signalling, especially by pathologically significant APC loss, in CRC. METHODS: Proteomic analyses were performed to evaluate the global effects of KYA1797K, Wnt/ß-catenin signalling inhibitor, on cellular proteins in CRC. The effects of APC-loss or Wnt ligand on the identified enzymes, PKM2 and LDHA, as well as Warburg effects were investigated. A linkage between activation of Wnt/ß-catenin signalling and cancer metabolism was analysed in tumour of Apcmin/+ mice and CRC patients. The roles of PKM2 in cancer metabolism, which depends on Wnt/ß-catenin signalling, were assessed in xenograft-tumours. RESULTS: By proteomic analysis, PKM2 and LDHA were identified as key molecules regulated by Wnt/ß-catenin signalling. APC-loss caused the increased expression of metabolic genes including PKM2 and LDHA, and increased glucose consumption and lactate secretion. Pathological significance of this linkage was indicated by increased expression of glycolytic genes with Wnt target genes in tumour of Apcmin/+ mice and CRC patients. Warburg effect and growth of xenografted tumours-induced by APC-mutated-CRC cells were suppressed by PKM2-depletion. CONCLUSIONS: The ß-catenin-PKM2 regulatory axis induced by APC loss activates the Warburg effect in CRC.

A mutant KRAS-induced factor REG4 promotes cancer stem cell properties via Wnt/ß-catenin signaling.

Mutant KRAS provides a driving force for enhancement of cancer stem cells (CSCs) characteristics contributing transformation of colorectal cancer (CRC) cells harboring adenomatous polyposis coli (APC) mutations. Here, we identified the factors mediating the promotion of CSCs properties induced by KRAS mutation through microarray analyses of genes specifically induced in CRC spheroids harboring both KRAS and APC mutations. Among them, REG4 was identified as a key factor since CRISPR/Cas9-mediated knockout of REG4 most significantly affected the stem cell characteristics in which CSCs markers were effectively suppressed. We show that REG4 mediates promotion of CSCs properties via Wnt/ß-catenin signaling in various in vitro studies including tumor organoid systems. Furthermore, expression patterns of CSCs markers and REG4 correlated in intestinal tumors from Apcmin/+ /KrasG12D LA2 mice and in CRC patient tissues harboring both KRAS and APC mutations. The role of REG4 in the tumor-initiating capacity accompanied by enhancement of CSCs characteristics was also revealed by NSG mice xenograft system. Collectively, our study highlights the importance of REG4 in promoting CSCs properties induced by KRAS mutation, and provides a new therapeutic strategy for CRC harboring both APC and KRAS mutations.

A Therapeutic Strategy for Chemotherapy-Resistant Gastric Cancer via Destabilization of Both ß-Catenin and RAS.

: Treatment of advanced gastric cancer patients with current standard chemotherapeutic agents frequently results in resistance, leading to poor overall survival. However, there has been no success in developing strategies to overcome it. We showed the expression levels of both ß-catenin and RAS were significantly increased and correlated in tissues of 756 gastric cancer (GC) patients and tissues of primary- and acquired-resistance patient-derived xenograft tumors treated with 5-fluorouracil and oxaliplatin modulated with leucovorin (FOLFOX). On the basis of our previous studies, where small molecules to suppress colorectal cancer (CRC) via degrading both ß-catenin and RAS were developed, we tested the effectiveness of KYA1797K, a representative compound functioning by binding axin, in the growth of GC cells. The efficacy test of the drugs using gastric tumor organoids of Apc1638N mice showed that the CD44 and ALDH1A3 cancer stem cell markers were induced by FOLFOX, but not by KYA1797K. KYA1797K also efficiently suppressed tumors generated by re-engrafting the FOLFOX-resistant patient-derived xenograft (PDX) tumors, which also showed resistance to paclitaxel. Overall, the small-molecule approach degrading both ß-catenin and RAS has potential as a therapeutic strategy for treating GC patients resistant to current standard chemotherapies.

Identification of Ras-degrading small molecules that inhibit the transformation of colorectal cancer cells independent of ß-catenin signaling.

Although the development of drugs that control Ras is an emerging topic in cancer therapy, no clinically applicable drug is currently available. We have previously utilized knowledge of the Wnt/ß-catenin signaling-dependent mechanism of Ras protein stability regulation to identify small molecules that inhibit the proliferation and transformation of various colorectal cancer (CRC) cells via degradation of both ß-catenin and Ras. Due to the absence of Ras degradation in cells expressing a nondegradable mutant form of ß-catenin and the need to determine an alternative mechanism of Ras degradation, we designed a cell-based system to screen compounds that degrade Ras independent of the Wnt/ß-catenin signaling pathway. A cell-based high-content screening (HCS) system that monitors the levels of EGFP-K-RasG12V was established using HCT-116 cells harboring a nondegradable mutant CTNNB1 (ΔS45). Through HCS of a chemical library composed of 10,000 compounds and subsequent characterization of hits, we identified several compounds that degrade Ras without affecting the ß-catenin levels. KY7749, one of the most effective compounds, inhibited the proliferation and transformation of CRC cells, especially KRAS-mutant cells that are resistant to the EGFR monoclonal antibody cetuximab. Small molecules that degrade Ras independent of ß-catenin may able to be used in treatments for cancers caused by aberrant EGFR and Ras.

Interaction of the Wnt/ß-catenin and RAS-ERK pathways involving co-stabilization of both ß-catenin and RAS plays important roles in the colorectal tumorigenesis.

Cancer development is usually driven by multiple genetic and molecular alterations rather than by a single defect. In the human colorectal cancer (CRC), series of mutations of genes are involved in the different stages of tumorigenesis. For example, adenomatous polyposis coli (APC) and KRAS mutations have been known to play roles in the initiation and progression of the tumorigenesis, respectively. However, many studies indicate that mutations of these two genes, which play roles in the Wnt/ß-catenin and RAS-extra-cellular signal regulated kinase (ERK) pathways, respectively, cooperatively interact in the tumorigenesis in several different cancer types including CRC. Both Apc and Kras mutations critically increase number and growth rate of tumors although single mutation of these genes does not significantly enhance the small intestinal tumorigenesis of mice. Both APC and KRAS mutations even result in the liver metastasis with inductions of the cancer stem cells (CSCs) markers in a mice xenograft model. In this review, we are going to describe the history for interaction between the Wnt/ß-catenin and RAS/ERK pathways especially related with CRC, and provide the mechanical basis for the cross-talk between the two pathways. The highlight of the crosstalk involving the stability regulation of RAS protein via the Wnt/ß-catenin signaling which is directly related with the cellular proliferation and transformation will be discussed. Activation status of GSK3ß, a key enzyme involving both ß-catenin and RAS degradations, is regulated by the status of the Wnt/ß-catenin signaling dependent upon extracellular stimuli or intracellular abnormalities of the signaling components. The levels of both ß-catenin and RAS proteins are co-regulated by the Wnt/ß-catenin signaling, and these proteins are overexpressed with a positive correlation in the tumor tissues of CRC patients. These results indicate that the elevation of both ß-catenin and RAS proteins is pathologically significant in CRC. In this review, we also will discuss further involvement of the increments of both ß-catenin and RAS especially mutant KRAS in the activation of CSCs and metastasis. Overall, the increments of ß-catenin and RAS especially mutant KRAS by APC loss play important roles in the cooperative tumorigenesis of CRC.

Predictors of the Use of Evidence-Based Interventions Among National Association of Social Work (NASW) Members.

There is growing emphasis on the use of evidence-based practice (EBP) in the field of social work.However, much remains unknown about the factors associated with the implementation of evidence-based interventions among social workers. In the current cross-sectional study the authors examined a sample of 180 NASW members who completed a survey assessing knowledge of EBP, organizational climate, and practitioner use of evidence-based interventions (EBI). Logistic regression was used to identify variables that predicted NASW members' self-reported use of EBI. Organizational climate factors and practitioner knowledge were predictive of self-reported EBI use in the sample of NASW members. Findings suggest that increased knowledge of evidence-based practice and higher levels of innovation and flexibility in the organizational climate may increase adoption of EBIs.

Optimization and modeling of reduction of wastewater sludge water content and turbidity removal using magnetic iron oxide nanoparticles (MION).

Economic and rapid reduction of sludge water content in sewage wastewater is difficult and requires special advanced treatment technologies. This study focused on optimizing and modeling decreased sludge water content (Y1) and removing turbidity (Y2) with magnetic iron oxide nanoparticles (Fe3O4, MION) using a central composite design (CCD) and response surface methodology (RSM). CCD and RSM were applied to evaluate and optimize the interactive effects of mixing time (X1) and MION concentration (X2) on chemical flocculent performance. The results show that the optimum conditions were 14.1 min and 22.1 mg L(-1) for response Y1 and 16.8 min and 8.85 mg L(-1) for response Y2, respectively. The two responses were obtained experimentally under this optimal scheme and fit the model predictions well (R(2) = 97.2% for Y1 and R(2) = 96.9% for Y2). A 90.8% decrease in sludge water content and turbidity removal of 29.4% were demonstrated. These results confirm that the statistical models were reliable, and that the magnetic flocculation conditions for decreasing sludge water content and removing turbidity from sewage wastewater were appropriate. The results reveal that MION are efficient for rapid separation and are a suitable alterative to sediment sludge during the wastewater treatment process.

Euodia sutchuenensis Dode extract stimulates osteoblast differentiation via Wnt/ß-catenin pathway activation.

The Wnt/ß-catenin pathway has a role in osteoblast differentiation and bone formation. We screened 100 plant extracts and identified an extract from Euodia sutchuenensis Dode (ESD) leaf and young branch as an effective activator of the Wnt/ß-catenin pathway. ESD extract increased ß-catenin levels and ß-catenin nuclear accumulation in murine primary osteoblasts. The ESD extract also increased mRNA levels of osteoblast markers, including RUNX2, BMP2 and COL1A1, and enhanced alkaline phosphatase (ALP) activity in murine primary osteoblasts. Both ESD extract-induced ß-catenin increment and ALP activation were abolished by ß-catenin knockdown, confirming that the Wnt/ß-catenin pathway functions in osteoblast differentiation. ESD extract enhanced terminal osteoblast differentiation as shown by staining with Alizarin Red S and significantly increased murine calvarial bone thickness. This study shows that ESD extract stimulates osteoblast differentiation via the Wnt/ß-catenin pathway and enhances murine calvarial bone formation ex vivo.