New perspectives on β-catenin control of cell fate and proliferation in colon cancer

Disintegration of Cav-1/β-catenin complex attenuates neuronal death after ischemia-reperfusion injury by promoting β-catenin nuclear translocation

BACKGROUND

The roles of Caveolin-1 (Cav-1) and the Wnt/β-catenin signaling pathways in cerebral ischemia-reperfusion (I/R) injury are well established. The translocation of β-catenin into the nucleus is critical for regulating neuronal apoptosis, repair, and neurogenesis within the ischemic brain. It has been reported that the scaffold domain of Caveolin-1 (Cav-1) (residues 95-98) interacts with β-catenin (residues 330-337). However, the specific contribution of the Cav-1/β-catenin complex to I/R injury remains unknown.

METHODS AND RESULTS

To investigate the mechanism underlying the involvement of the Cav-1/β-catenin complex in the subcellular translocation of β-catenin and its subsequent effects on cerebral I/R injury, we treated ischemic brains with ASON (Cav-1 antisense oligodeoxynucleotides) or FTVT (a competitive peptide antagonist of the Cav-1 and β-catenin interaction). Our study demonstrated that the binding of Cav-1 to β-catenin following I/R injury prevented the nuclear accumulation of β-catenin. Treatment with ASON or FTVT after I/R injury significantly increased the levels of nuclear β-catenin. Furthermore, ASON reduced the phosphorylation of β-catenin at Ser33, Ser37, and Thr41, which contributes to its proteasomal degradation, while FTVT increased phosphorylation at Tyr333, which is associated with its nuclear translocation.

CONCLUSIONS

The above results indicate that the formation of the Cav-1/β-catenin complex anchors β-catenin in the cytoplasm following I/R injury. Additionally, both ASON and FTVT treatments attenuated neuronal death in ischemic brains. Our study suggests that targeting the interaction between Cav-1 and β-catenin serve as a novel therapeutic strategy to protect against neuronal damage during cerebral injury.

Phenotypic dento-osseous characterization of a Brazilian family with Familial Adenomatous Polyposis

OBJECTIVE

To perform a phenotypic characterization of the dento-osseous anomalies in a Brazilian family with Familial Adenomatous Polyposis (FAP) and to investigate the adenomatous polyposis coli (APC) causative variant.

DESIGN

The study included a family of 14 individuals (Group A: affected; Group B: non-affected). The frequency of radiographic findings in both groups was evaluated according to the Dental Panoramic Radiograph Score (DPRS) diagnostic method. The accuracy and reproducibility of DPRS were tested. The DNA was isolated from the index patient's saliva and submitted to whole-exome and Sanger sequencing approach.

RESULTS

DPRS ≥ 7 was observed in 80 % of Group A but in none of Group B. The most common findings in Group A were dense bone islands (60 %), hazy sclerosis (40 %), osteomas (40 %), and supernumerary tooth (20 %). DPRS has proved to be a reliable method while DPRS ≥ 5 and DPRS ≥ 7 were taken as positive for FAP, and reproducible diagnosis test considering that the evaluators correctly identified the affected patients (Kappa agreement>0.8, p = 0.002). A nonsense heterozygous mutation in the APC gene (c.1370C > G; p.Ser457*) of the index case was detected.

CONCLUSION

FAP patients have a higher frequency of dento-osseous anomalies (p = 0.005). Bone abnormalities were more prevalent than dental anomalies (p = 0.001). Thus, FAP patients should be referred for dental examination and genetic counseling to perform early diagnosis of dento-osseous anomalies and evaluate the implications of the molecular findings in each particular family.

PPARG expression in colorectal cancer and its association with staging and clinical evolution

Purpose

To evaluate the gene expression of peroxisome proliferator activated receptors gamma (PPARG) in colorectal tumors and to correlate this data with clinical variables of the patients.

Methods

We analyzed the gene expression of PPARG in 50 samples of colorectal tumors using real-time reverse transcription polymerase chain reaction, and 20 adjacent normal tissue samples as control. The results of these quantifications were correlated with the respective patients’ medical records’ clinical information.

Results

PPARG expression was not different in the tumor tissue compared to the control tissue. Patients older than 60 years, histological type with mucinous differentiation, more advanced staging at the time of diagnosis, and patients who evolved with recurrence of the disease or death did not present higher PPARG expression.

Conclusion

Expression of PPARGD was not associated with worse prognosis.

RETRACTED: KYA1797K down-regulates PD-L1 in colon cancer stem cells to block immune evasion by suppressing the β-catenin/STT3 signaling pathway

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Concern was raised about the reliability of the Western blot results in Figures 2B,C,D+E and 3A,B,C,F+G, and a suspected image duplication within Figure 1B, as they appeared to feature in previous publications, as detailed here: https://pubpeer.com/publications/DCF33B20702DC3AE0C9D750A90174B; and here: https://docs.google.com/spreadsheets/d/1r0MyIYpagBc58BRF9c3luWNlCX8VUvUuPyYYXzxWvgY/edit#gid=262337249. The journal requested the corresponding author comment on these concerns and to provide the raw data. The corresponding author, Xinguo Su, stated “…the researchers responsible for technical support and data storage have left due to the impact of the epidemic, and along with much of the data involved in the paper”. The editorial team were not convinced that the raw Western blot data that was shared represented uncropped and unadjusted source data, so its veracity could not be adequately confirmed. The Editor-in-Chief decided to retract the article.

miR-512-5p suppresses the progression of non-small cell lung cancer by targeting β-catenin

The oncogenic protein β-catenin is regulated by microRNAs (miRs) in non-small cell lung cancer (NSCLC). miR-512-5p is downregulated in NSCLC compared with healthy tissues and exhibits a tumour-suppressive effect. To study whether miR-512-5p acts on β-catenin to exert its anticancer effect in NSCLC, miR-512-5p mimic and inhibitor were transfected into NSCLC A549 and H1975 cells. miR-512-5p mimic inhibited the invasion of NSCLC cells and increased apoptosis, which suggested an inhibitory effect of miR-512-5p in NSCLC progression in vitro. By contrast, transfection with the miR-512-5p inhibitor resulted in the opposite effects. A dual-luciferase assay demonstrated that miR-512-5p complementarily bound to the 3′-untranslated region of β-catenin. miR-512-5p mimic suppressed the transcription and translation of β-catenin and reduced the expression of the downstream oncogenes cyclin D1 and matrix metalloproteinases, leading to the inhibition of Wnt/β-catenin signalling and subsequent inhibition of NSCLC tumourigenesis in vitro. In conclusion, miR-512-5p may function as a tumour suppressor in NSCLC by inhibiting the Wnt/β-catenin pathway.

Anti-Invasion and Antimetastatic Effects of Porcine Recombinant NK-lysin on SMMC-7721 Human Hepatocellular Carcinoma Cells

The high invasion and metastasizing abilities of hepatocellular carcinoma (HCC) are the primary reasons for the high mortality rate of patients. Therefore, identification of agents to inhibit invasion and metastasis is very important for treatment of HCC. We analyzed the anti-invasion and antimetastatic effects of porcine recombinant NK-lysin, which was designed and expressed in vitro by our research group, on SMMC-7721 hepatocellular carcinoma cells via wound-healing assays, adhesion assays, invasion assays, real-time polymerase chain reaction (PCR), and Western blot analysis. MTT assay results indicated that NK-lysin inhibited the growth of SMMC-7721 cells in a dose- and time-dependent manner. NK-lysin reduced the ability of cell migration, adhesion, and invasion. Based on gene and protein expression analysis, NK-lysin decreased β-catenin and MMP-2 expression. These results suggested that NK-lysin has anti-invasion and antimetastatic effects on hepatocellular carcinoma cells in vitro by reducing the level of the β-catenin and MMP-2.

Ethanolic extract of Brucea javanica inhibit proliferation of HCT-116 colon cancer cells via caspase activation

Brucea javanica (L.) Merr. is a well-known plant in Chinese System of Medicine. Its fruits and seeds have been reported to possess curative properties against various ailments. The chemical constituents and biological activity of this plant have been an interesting area in plant and chemistry medicine. The aim of this study is to evaluate the antiproliferative effects of the B. javanica extract against a colon cancer cell line and identification of the chemical components derived from the extract. An ethanolic extract from B. javanica fruits was prepared by cold maceration method, subjected to LC-MS profiling to elucidate the composition abbreviated as BJEE. The extract was screened for the cytotoxicity effects on HCT-116 colon cancer cells via MTT and LDH methods. Additionally, AO/PI staining verified apoptosis features in HCT-116 cells through microscopic analysis. ROS, caspase activity, and gene expression has been performed to identify its possible mechanism of actions which contribute to apoptosis. Output data from this study showed BJEE inhibited the cell proliferation of HCT-116 colon cancer cells at IC50 value of 8.9 ± 1.32 (μg mL-1) and significantly increased the levels of caspase-8, 9, and 3/7 in treated cells in comparison to untreated. The changes in expression of caspase genes and some apoptosis genes like Bax and Bcl-2 were confirmed using RT-PCR. Phytochemical analysis by LC-MS identified six major active compounds (bruceine D, isobrucein A, quassimarin, C16 sphinganine, phytosphingosine, and enigmol) in BJEE that may play a key role in cell apoptosis. The current study showed BJEE could be a promising agent for colorectal cancer therapy by significant increase in caspase activity level, and up-regulation of the specific apoptotic genes.

Tianfoshen oral liquid: a CFDA approved clinical traditional Chinese medicine, normalizes major cellular pathways disordered during colorectal carcinogenesis

Colorectal cancer remains the third leading cause of cancer death worldwide, suggesting exploration of novel therapeutic avenues may be useful. In this study, therefore, we determined whether Tianfoshen oral liquid, a Chinese traditional medicine that has been used to treat non-small cell lung cancer, would be therapeutically beneficial for colorectal cancer patients. Our data show that Tianfoshen oral liquid effectively inhibits growth of colorectal cancer cells both in vitro and in vivo. We further employed a comprehensive strategy that included chemoinformatics, bioinformatics and network biology methods to unravel novel insights into the active compounds of Tianfoshen oral liquid and to identify the common therapeutic targets and processes for colorectal cancer treatment. We identified 276 major candidate targets for Tianfoshen oral liquid that are central to colorectal cancer progression. Gene enrichment analysis showed that these targets were associated with cell cycle, apoptosis, cancer-related angiogenesis, and chronic inflammation and related signaling pathways. We also validated experimentally the inhibitory effects of Tianfoshen oral liquid on these pathological processes, both in vitro and in vivo. In addition, we demonstrated that Tianfoshen oral liquid suppressed multiple relevant key players that sustain and promote colorectal cancer, which is suggests the potential therapeutic efficacy of Tianfoshen oral liquid in future colorectal cancer treatments.

Effects of SOST Gene Silencing on Proliferation, Apoptosis, Invasion, and Migration of Human Osteosarcoma Cells Through the Wnt/β-Catenin Signaling Pathway

Our study explored the effects of SOST gene silencing on the proliferation, apoptosis, invasion, and migration of human osteosarcoma cells through Wnt/β-catenin signaling pathway. Fresh tissues were obtained from 108 patients with osteosarcoma and 46 patients with osteochondroma. Human osteosarcoma cells (MG-63, U2-OS, HOS, and Saos-2) and normal osteoblast (hFoB1.19) were selected and cultured. Osteosarcoma cells were grouped randomly into the blank group, the scrambled control group, and the SOST-siRNA group. Cell proliferation was determined by MTT assay. Cell cycle and apoptosis were tested by flow cytometry. Transwell and scratch test were performed to determine cell invasion and migration. The qRT-PCR and Western blotting were used to detect mRNA and protein expression level of sclerostin, Wnt1, β-catenin, C-Myc, Cyclin D1, and MMP-7. The activity of caspase-3 was assessed by immunocytochemistry. Alkaline phosphatase (ALP) activity was measured using P-nitrophenylphosphate as a substrate. Low SOST mRNA and sclerostin protein expression levels were observed in osteosarcoma tissues and cells. Compared with the blank and scrambled control groups, sclerostin expression, apoptotic cells, ALP activity, and caspase-3 activity were down-regulated, while the proliferation, invasion, and migration abilities of osteosarcoma cells were evidently enhanced in the SOST-siRNA group. After SOST gene silencing, the mRNA and protein expression levels of Wnt1, β-catenin, C-Myc, Cyclin D1, and MMP-7 in osteosarcoma cells and β-catenin protein expression levels in the nucleus and cytoplasm were significantly elevated. SOST gene silencing promotes the proliferation, invasion, and migration, and inhibits apoptosis of osteosarcoma cells by activating Wnt/β-catenin signaling pathway.

Secreted HMGB1 from Wnt activated intestinal cells is required to maintain a crypt progenitor phenotype

BACKGROUND AND AIMS

Colorectal cancer (CRC) arises via multiple genetic changes. Mutation of the tumour suppressor gene APC, a key regulator of Wnt signalling, is recognised as a frequent early driving mutation in CRC. We have previously shown that conditional loss of Apc within the murine small intestine (Apcfloxmice) results in acute Wnt signalling activation, altered crypt-villus architecture and many hallmarks of neoplasia. Our transctipomic profiling (Affymetrix Microarrays) and proteomic profiling (iTRAQ-QSTAR) of Apc-deficient intestine inferred the involvement of High Mobility Group Box 1 (Hmgb1) in CRC pathogenesis. Here we assess the contribution of HMGB1 to the crypt progenitor phenotype seen following Apc loss.

RESULTS

Elevated HMGB1 was confirmed in intestinal epithelia and serum following conditional loss of Apc. Treatment of Apcflox mice with anti-HMGB1 neutralising antibody significantly reduced many of the crypt progenitor phenotypes associated with Apc loss; proliferation and apoptosis levels were reduced, cell differentiation was restored and the expansion of stem cell marker expression was eradicated.

METHODS

Hmgb1 levels in intestinal epithelia and serum in Apcflox and ApcMin mice were assessed using qRT-PCR, Western blot and ELISA assays. The functional importance of elevated extracellular Hmgb1 was assessed using an anti-HMGB1 neutralising antibody in Apcflox mice.

CONCLUSIONS

HMGB1 is expressed and secreted from intestinal epithelial cells in response to Wnt signalling activation. This secreted HMGB1 is required to maintain nearly all aspects of the crypt progenitor phenotype observed following Apc loss and add to the body of accumulating evidence indicating that targeting HMGB1 may be a viable novel therapeutic approach.

Loss of TFF1 promotes Helicobacter pylori-induced β-catenin activation and gastric tumorigenesis

Using in vitro and in vivo models, we investigated the role of TFF1 in suppressing H. pylori-mediated activation of oncogenic β-catenin in gastric tumorigenesis. A reconstitution of TFF1 expression in gastric cancer cells decreased H. pylori-induced β-catenin nuclear translocation, as compared to control (p < 0.001). These cells exhibited significantly lower β-catenin transcriptional activity, measured by pTopFlash reporter, and induction of its target genes (CCND1 and c-MYC), as compared to control. Because of the role of AKT in regulating β-catenin, we performed Western blot analysis and demonstrated that TFF1 reconstitution abrogates H. pylori-induced p-AKT (Ser473), p-β-catenin (Ser552), c-MYC, and CCND1 protein levels. For in vivo validation, we utilized the Tff1-KO gastric neoplasm mouse model. Following infection with PMSS1 H. pylori strain, we detected an increase in the nuclear staining for β-catenin and Ki-67 with a significant induction in the levels of Ccnd1 and c-Myc in the stomach of the Tff1-KO, as compared to Tff1-WT mice (p < 0.05). Only 10% of uninfected Tff1-KO mice, as opposed to one-third of H. pylori-infected Tff1-KO mice, developed invasive adenocarcinoma (p = 0.03). These findings suggest that loss of TFF1 could be a critical step in promoting the H. pylori-mediated oncogenic activation of β-catenin and gastric tumorigenesis.

Heterophyllin B inhibits the adhesion and invasion of ECA-109 human esophageal carcinoma cells by targeting PI3K/AKT/β-catenin signaling

The present study aimed to measure the effect of heterophyllin B (HB) on the adhesion and invasion of ECA-109 human esophageal carcinoma cells, and examine the possible mechanism involved. A Cell Counting kit 8 assay was performed to determine the cell viability. Cell adhesion and invasion were determined following treatment of the ECA-109 cells with HB (0, 10, 25 and 50 µM) for 24 h. The levels of phosphorylated (p-)ATK and p-phosphoinositide 3-kinase (PI3K), and the protein levels of β-catenin were measured using western blot analysis. The mRNA and protein expression levels of E-cadherin, vimentin, snail, matrix metalloproteinase (MMP)2 and MMP9 were detected using reverse transcription-quantitative polymerase chain reaction and western blot analyses, respectively. HB (10, 25 and 50 µM) significantly suppressed the adhesion and invasion of the ECA-109 human esophageal carcinoma cells in a dose-dependant manner. The expression levels of p-ATK, p-PI3K and β-catenin were markedly decreased. The expression of E-cadherin was promoted, whereas the expression levels of snail, vimentin, MMP 2 and MMP 9 were decreased significantly in the ECA-109 cells treated with HB. In addition, HB inhibited the adhesion and invasion induced by PI3K activating peptide in the ECA-109 cells, and the protein expression levels were also adjusted. These results suggested that HB effectively suppressed the adhesion and invasion of the human esophageal carcinoma cells by mediating the PI3K/AKT/β-catenin pathways and regulating the expression levels of adhesion- and invasion-associated genes.

Evaluation of the correlation of KAI1/CD82, CD44, MMP7 and β-catenin in the prediction of prognosis and metastasis in colorectal carcinoma

BACKGROUND

To investigate the relationship of KAI1/CD82, CD44, matrix metalloproteinase 7 (MMP7) and β-catenin, and examine its association with clinicopathological features, metastasis and prognosis in colorectal carcinoma (CRC).

METHODS

Immunohistochemical (IHC) analysis was used to detect the expression of KAI1/CD82, CD44, MMP7 and β-catenin in 174 archival surgical specimens of human CRC. Furthermore, clinicopathological features such as age, sex and so on were also collected retrospectively.

RESULTS

CD44, MMP7 and β-catenin expression was positively associated with distant metastasis, lymph node metastasis and tumor-node-metastasis (TNM) stage. However, decreased KAI1/CD82 expression correlated significantly with distant metastasis, lymph node metastasis and TNM stage. KAI1/CD82 expression showed a negative correlation with CD44, MMP7 and β-catenin. Furthermore, β-catenin expression showed a positive correlation with CD44 and MMP7. Multivariate logistic regression analysis showed that KAI1/CD82 and β-catenin expression were significantly associated with lymph node metastasis and KAI1/CD82 was significantly associated with distant metastasis. Kaplan-Meier analysis revealed that CD44, MMP7 and β-catenin expression was negatively correlated with overall survival (OS), while KAI1/CD82 expression was positively correlated with OS. Low KAI1/CD82 expression and high expression of CD44, MMP7 and β-catenin was associated with a poor prognosis in CRC. Multivariate Cox regression analysis indicated that the expression of KAI1/CD82, MMP7 and β-catenin were independent predictors of OS in CRC.

CONCLUSION

The expression of KAI1/CD82, CD44, MMP7 and β-catenin is related to tumor metastasis and prognosis in CRC. Combined detection of these factors may be of significant value in predicting the prognosis and metastasis in CRC patients.

Synergistic apoptosis-inducing effect of aspirin and isosorbide mononitrate on human colon cancer cells

Aspirin and isosorbide mononitrate (ISMN) are two commonly used drugs, which are clinically applied for the treatment of inflammatory and cardiovascular diseases, respectively. Recently, aspirin has attracted interest due to its potential application for the treatment of cancer, particularly colon cancer. NO-aspirin, an aspirin derivative containing a covalently bound NO-donating moiety, has been proven to be an effective anti‑tumor agent with apoptosis-inducing ability. In the present study, ISMN was used as an NO donor and its synergic effect with aspirin was assessed in human colon cancer cells. In vitro, an MTT assay demonstrated that ISMN had a synergistic effect on the growth inhibitory effects of aspirin on HCT116 and SW620 colon cancer cells, while the growth of EA.hy926 normal endothelial cells was unaffected. This synergistic anti‑tumor effect was further validated in vivo using nude mouse HCT116 cell xenograft model. Observation of nuclear morphology, Annexin V-fluorescein isothiocyanate/propidium iodide double staining and a caspase-3 activity assay suggested that the combination of the two drugs induced apoptosis in HCT116 cells. Furthermore, the molecular mechanisms of the apoptotic effect of the drugs was assessed using an NO release assay, reverse transcription quantitative polymerase chain reaction analysis, western blot analysis and a luciferase reporter assay. It was certified that the increase in the amount of NO release, the decrease in the luciferase promoter activity and the expression of cyclin D1 and c-myc in HCT116 cells were affected by aspirin and ISMN in a synergistic manner. In conclusion, the present study was the first, to the best of our knowledge, to report on the synergistic apoptosis-inducing effects of aspirin and ISMN in human colon cancer cells, which were mediated via Wnt and NO signaling pathways. The results of the present study will facilitate the development of future therapeutic strategies.

Novel cancer chemotherapy hits by molecular topology: dual Akt and Beta-catenin inhibitors

Background and Purpose

Colorectal and prostate cancers are two of the most common types and cause of a high rate of deaths worldwide. Therefore, any strategy to stop or at least slacken the development and progression of malignant cells is an important therapeutic choice. The aim of the present work is the identification of novel cancer chemotherapy agents. Nowadays, many different drug discovery approaches are available, but this paper focuses on Molecular Topology, which has already demonstrated its extraordinary efficacy in this field, particularly in the identification of new hit and lead compounds against cancer. This methodology uses the graph theoretical formalism to numerically characterize molecular structures through the so called topological indices. Once obtained a specific framework, it allows the construction of complex mathematical models that can be used to predict physical, chemical or biological properties of compounds. In addition, Molecular Topology is highly efficient in selecting and designing new hit and lead drugs. According to the aforementioned, Molecular Topology has been applied here for the construction of specific Akt/mTOR and β-catenin inhibition mathematical models in order to identify and select novel antitumor agents.

Experimental Approach

Based on the results obtained by the selected mathematical models, six novel potential inhibitors of the Akt/mTOR and β-catenin pathways were identified. These compounds were then tested in vitro to confirm their biological activity.

Conclusion and Implications

Five of the selected compounds, CAS n° 256378-54-8 (Inhibitor n°1), 663203-38-1 (Inhibitor n°2), 247079-73-8 (Inhibitor n°3), 689769-86-6 (Inhibitor n°4) and 431925-096 (Inhibitor n°6) gave positive responses and resulted to be active for Akt/mTOR and/or β-catenin inhibition. This study confirms once again the Molecular Topology’s reliability and efficacy to find out novel drugs in the field of cancer.