Wnt1 and SFRP1 as potential prognostic factors and therapeutic targets in cutaneous squamous cell carcinoma

Higher immunoexpression of CK14 from the Wnt-1/β-catenin pathway in the development of odontomas

Tooth development depends on a series of reciprocal signaling interactions between the oral epithelium and ectomesenchyme. This study aimed to investigate the role of CK14, a protein involved in Wnt-1/β-catenin signaling, in odontogenesis and the development of odontomas. This cross-sectional, retrospective, immunohistochemical study analyzed 30 compound odontomas, 30 complex odontomas, and 17 tooth germs. Higher immunoexpression of CK14 was observed in odontogenic epithelial cells of tooth germs (p < 0.001) and odontogenic epithelial cells of odontomas (p < 0.001). There was higher immunoexpression of Wnt-1 and β-catenin proteins in epithelial cells of tooth germs (p = 0.002 and p < 0.001, respectively), as well as in the ectomesenchyme of odontomas (p = 0.003 and p < 0.001, respectively). β-Catenin was moderately and significantly correlated with CK14 in the membrane of reduced enamel epithelial cells in odontomas (p = 0.007). Higher immunoexpression of CK14 was observed in the odontogenic epithelium during the bud and cap stages and lower immunoexpression in the internal enamel epithelium during the bell stage. In odontomas, lower expression of Wnt-1/β-catenin and higher immunoexpression of CK14 were found in odontogenic epithelial cells, especially adjacent to the mineralized material resembling the tooth formed in these lesions.

UVB-induced SFRP1 methylation potentiates skin damage by promoting cell apoptosis and DNA damage

In response to the accumulation of genetic mutations and cellular changes, ultraviolet radiation B (UVB) skin lesions undergo dysplasia and transform into a cutaneous squamous cell carcinoma (CSCC). Consistent with our previous findings that secreted frizzled-related protein 1 (SFRP1), a member of the SFRP gene family, was downregulated in human CSCC tissue samples, we found a significant downregulation of SFRP1 in HaCaT, A431, and SCL-1 cells after UVB irradiation. DNA methyltransferase 1 (DNMT1) was significantly increased in CSCC tissues as well as UVB-exposed A431 and SCL-1 cells. Bisulfite genomic sequencing analysis showed that the downregulation of SFRP1 was mainly due to methylation of the SFRP1 promoter, as indicated by increased methylation rate of SFRP1 after UVB irradiation in HaCaT cells. Moreover, demethylation treatment with 5-aza'-deoxycytidine (5-AzaC) increased SFRP1 expression and reduced the methylation rate of SFRP1 in HaCaT cells. Flow cytometry analyses demonstrated that 5-AzaC treatment or overexpression of SFRP1 ameliorated UVB-induced apoptosis, while knockdown of SFRP1 promoted UVB-induced apoptosis in HaCaT cells. In addition, a comet assay confirmed that 5-AzaC treatment reduced DNA damage following UVB irradiation, while knockdown of SFRP1 enhanced DNA damage following UVB irradiation. In conclusion, our study identified DNA methylation of SFRP1 as a key mediator in the UVB-induced apoptosis of keratinocytes. These findings indicate that reinforcing SFRP1 defenses by 5-AzaC may help prevent UVB-induced skin damage.

Tamoxifen Downregulates the Expression of Notch1 and DLL1 Genes in MKN-45 Gastric Cancer Cells

PURPOSE

Gastric cancer is one of the most prevalent cancers worldwide and the second most common cause for cancer associated mortality. Anti-tumor effects of tamoxifen in breast cancer are well-established. However, no study has so far investigated the effects of tamoxifen on gene expression of Notch1 and DLL1 in gastric cancer cell line. The present study was conducted to explore the effects of tamoxifen, as a repurposed drug, on gene expression of Notch1 and DLL1 in MKN-45, a gastric cancer cell line.

METHODS

MKN-45 cells were cultured in DMEM/F12 medium containing 10% FBS. Cytotoxic effects of tamoxifen on these cells at various concentrations were evaluated by trypan blue exclusion assay. For gene expression analysis, the cells were first incubated with 100 μM tamoxifen followed by total RNA extraction from treated and control cells. Then, cDNA was synthesized. Quantitative real-time PCR using specific primers for Notch1 and DLL1 was performed to assess the effect of tamoxifen on the transcript of them.

RESULTS

Treatment with tamoxifen decreased viability of MKN-45 cells in a dose-dependent manner. CC₅₀ was estimated to be around 200 μM. Also, tamoxifen at the dose of 100 μM could significantly downregulate mRNA levels of both Notch1 and DLL1 genes as compared with untreated cells by 24% and 92%, respectively.

CONCLUSION

Based on these results, tamoxifen interferes with Notch signaling pathway through downregulating the expression of Notch1 and DLL1 genes and this could be regarded as a mechanism for its anti-cancer effects in this malignant disease.

Evaluating antitumor activity of antiglypican-3 therapy in experimentally induced skin cancer in mice

Glypican-3 (GPC3) is considered as a cell surface heparan sulfate proteoglycan. It is overexpressed in skin cancer and promotes tumor progression and pathogenicity. Therefore, we aimed to find out the therapeutic effects of immuno-suppressing GPC3 in skin cancer experimentally induced in mice as well as to underline molecular mechanisms especially inflammatory and apoptotic pathways. Skin cancer was experimentally induced in mice by repeated rubbing of mice skin with 7,12-dimethylbenz (a) anthracene. Mice were injected with anti-GPC3. Skin samples were isolated to investigate the gene and protein expression of GPC3, Wnt-1, NFκB, TNF-α, IGF-1, p38 MAPK and caspase-3 using PCR, Western blot and ELISA. Moreover, skin sections were stained with hematoxylin and eosin. Treating skin cancer mice with anti-GPC3 significantly blocked GPC3, which is accompanied by amelioration of skin cancer-induced increase in the numbers of tumors and scratching behavior. Moreover, anti-GPC3 attenuated skin cancer-induced increase in the expression of Wnt-1, NFκB, TNF-α, IGF-1, p38 MAPK and caspase-3. In parallel, anti-GPC3 reduced degeneration of melanocyte cells and reduced phagocytic cells epidermal hyperplasia and dysplasia in skin sections stained with hematoxylin and eosin stain. In conclusion, anti-GPC3 produced anti-tumor effects against skin cancer, which can be explained by reduction in both inflammatory and apoptotic pathways. Targeting GPC3 is a promising therapeutic approach for skin cancer.

Comprehensive bioinformatic analysis of Wnt1 and Wnt1-associated diseases

Wnt1 is the first member of the Wnt family that was identified. It is phylogenetically conserved and essential for oncogenesis and multiple developmental processes. This study has summarized diseases and mutations related to Wnt1. Wnt1 is involved in various cancers, genetic type XV osteogenesis imperfecta, osteoporosis, and neurological diseases. The expression of Wnt1 in normal tissues and different types of cancers and the potential survival of cancer were analyzed using experiment-based bioinformatic analysis. Systematic analysis indicated that abnormal expression of Wnt1 is significantly associated with cancers, such as kidney renal carcinoma, hepatocellular carcinoma, thyroid carcinoma, head and neck squamous cell carcinoma, and uterine corpus endometrial carcinoma. GeneMANIA and STRING predicted that 32 proteins were involved with Wnt1 in Wnt signaling pathways and sorting and secretion of Wnts. These interacting molecules significantly co-occurred according to cBioPortal analysis. Thirty-three genes with an alteration frequency of more than 50% were observed in several cancers like esophageal squamous cell carcinoma, melanoma, and non-small cell lung cancer. Functional and experiment-based bioinformatics indicated that Wnt1 may act as a target of a potential biomarker for various types of human cancers. Wnt1 and other Wnt1-related proteins and signaling pathways may be ways to treat osteoporosis.

AXIN2 and SNAIL expression predict the risk of recurrence in cutaneous squamous cell carcinoma after Mohs micrographic surgery

Recurrence is a common complication observed during cutaneous squamous cell carcinoma (cSCC) treatment; however, biomarkers for predicting recurrence in cSCC remain unknown. The present study aimed to investigate the predictive value of axis inhibition protein 2 (AXIN2) and SNAIL expression in cSCC recurrence. AXIN2 and SNAIL expression was evaluated using immunohistochemistry in 111 cSCC tissue samples obtained from 18 patients who presented recurrence (recurrence interval, 1–91 months) and 93 patients who did not experience recurrence following Mohs micrographic surgery (MMS) during the follow-up period (156 months). Nomogram construction was performed using patients' clinicopathological characteristics and AXIN2 and SNAIL protein expression. The results demonstrated that high AXIN2 (histoscore >100) and SNAIL (histoscore >100) expression was detected in 35 and 44 cSCC tissues, respectively. Furthermore, the expression levels of AXIN2 and SNAIL were significantly associated in patients with cSCC (P=0.001). AXIN2 and SNAIL expression levels were significantly associated with tumor size (P=0.021 and P=0.044, respectively) and recurrence of cSCC (P=0.017 and P=0.042, respectively). In addition, the results of the Kaplan-Meier curve analysis revealed that recurrence-free survival was significantly associated with tumor size (P=0.025), differentiation status (P<0.001), AXIN2 expression (P=0.001) and SNAIL expression (P=0.001). Furthermore, the results of the multivariate analysis demonstrated that age (P=0.043), AXIN2 expression (P=0.001) and SNAIL expression (P=0.045) were independent risk factors for cSCC recurrence in the present cohort. A nomogram for predicting the 1-, 2-, 3-, and 5-year recurrence-free survival was developed for patients with cSCC by including independent risk factors with a concordance index of 0.75. The results suggested that high AXIN2 and SNAIL expression may be considered as potential risk factors for cSCC recurrence. This nomogram may therefore be useful to assess the probability of recurrence in patients with cSCC following MMS.

Blocking Wnt as a therapeutic target in mice model of skin cancer

Wnt pathway plays an important role in controlling metabolism in cancer cells. It acts as positive modulator for both cell inflammation, through activation of NFκB, and fibrosis, through activation of TGF-β. Therefore, the aim of this study is to investigate the therapeutic effects of blocking Wnt pathway by IWP12 on skin cancer by studying its effects on skin cancer-induced inflammation and fibrosis in a mice model of skin cancer. Skin cancer was induced by application of 7,12-dimethylbenz[a]anthracene (DMBA) and croton oil on the dorsal skin of mice. Dorsal skin was removed for estimation of gene and protein expression of Wnt, β-catenin, SMAD, TGF-β, NFκB, TNF-α, IL-4 and IL-10. Part of the skin is stained with hematoxylin/eosin for assessment of cell structure. Treatment of mice with IWP12 completely blocked Wnt in skin cancer mice without affecting the control mice. Skin of tumorigenic mice showed marked skin hyperkeratosis, parakeratosis, acanthosis and dysplasia. Treatment with IWP12 markedly attenuated epidermal atypia and hyperplasia. In addition, IWP12 reduced expression of β-catenin, SMAD, TGF-β, NFκB and TNF-α associated with increase in the expression of IL-4 and IL-10. In conclusion, blocking Wnt production ameliorated skin cancer via blocking pro-inflammatory cytokines and enhancing the anti-inflammatory cytokines. Moreover, blocking Wnt attenuated skin cancer-induced activation of fibrosis pathway.

In Silico Approach for Immunohistochemical Evaluation of a Cytoplasmic Marker in Breast Cancer

Breast cancer is the most frequently diagnosed cancer in women and the second most common cancer overall, with nearly 1.7 million new cases worldwide every year. Breast cancer patients need accurate tools for early diagnosis and to improve treatment. Biomarkers are increasingly used to describe and evaluate tumours for prognosis, to facilitate and predict response to therapy and to evaluate residual tumor, post-treatment. Here, we evaluate different methods to separate Diaminobenzidine (DAB) from Hematoxylin and Eosin (H&E) staining for Wnt-1, a potential cytoplasmic breast cancer biomarker. A method comprising clustering and Color deconvolution allowed us to recognize and quantify Wnt-1 levels accurately at pixel levels. Experimental validation was conducted using a set of 12,288 blocks of m×n pixels without overlap, extracted from a Tissue Microarray (TMA) composed of 192 tissue cores. Intraclass Correlations (ICC) among evaluators of the data of 0.634, 0.791, 0.551 and 0.63 for each Allred class and an average ICC of 0.752 among evaluators and automatic classification were obtained. Furthermore, this method received an average rating of 4.26 out of 5 in the Wnt-1 segmentation process from the evaluators.

Specific knockdown of HOXB7 inhibits cutaneous squamous cell carcinoma cell migration and invasion while inducing apoptosis via the Wnt/β-catenin signaling pathway

Metastatic cutaneous squamous cell carcinoma (CSCC) is a major cause of death associated with nonmelanoma skin cancer. The involvement of homeobox B7 ( HOXB7) in cancers has been reported. Thus, the current study intends to explore the effect of HOXB7 on CSCC and its relationship with the Wnt/β-catenin signaling pathway. Initially, microarray-based gene expression profiling of CSCC was performed, and HOXB7 was identified as an upregulated gene based on the microarray data of GSE66359 . Following this, the experimental results indicated that HOXB7 and β-catenin formed a composite, demonstrating that endogenous HOXB7 binds to β-catenin. Subsequently, CSCC cells were treated with siRNA against HOXB7 or an inhibitor of the Wnt/β-catenin signaling pathway to analyze any underlying regulatory mechanism of HOXB7 on the CSCC cells. Tumor growth involving xenografts in nude mice was also observed so as to explore whether or not HOXB7 could regulate subcutaneous tumor growth through in vivo culturing. To investigate the potential effects of HOXB7 on the Wnt/β-catenin signaling pathway, we determined the expression of HOXB7 and downstream genes of the Wnt/β-catenin signaling pathway. Notably, siRNA-mediated knockdown of HOXB7 inhibited the activation of the Wnt/β-catenin signaling pathway, thereby impeding the progression of cell viability, migration, and invasion as well as of the tumor growth, although contrarily facilitating cell apoptosis. Taken together, silencing of the HOXB7 has the mechanism of inactivating the Wnt/β-catenin signaling pathway, thereby accelerating cell apoptosis and suppressing cell migration and invasion in CSCC, which could provide a candidate target for the CSCC treatment.

Secreted frizzled-related protein 1 (SFRP1) gene methylation changes in the human lung adenocarcinoma cells treated with L-securinine

Lung cancer remains the leading cause of cancer-related death worldwide. It is important to explore the biomarkers of diagnosis and prognosis in lung cancer. To evaluate the cytotoxicity of L-securinine and the expression and methylation of secreted frizzled-related proteins (SFRPs) genes in the human lung adenocarcinoma cells, cell counting kit-8 (CCK-8) assay was used to assess the proliferation of lung adenocarcinoma cells treated with L-securinine. Quantitative real-time PCR (qRT-PCR) and bisulfite sequencing PCR were used to detect the expression and the DNA methylation of SFRPs genes, respectively. L-securinine inhibited the proliferation of lung adenocarcinoma cells and induced the upregulation of SFRP1 gene expression and the methylation changes at CpG sites in the SFRP1 promoter region. L-securinine was a potential agent in the treatment of lung cancer by upregulation of SFRP1 gene expression and changing the SFRP1 gene methylation.

Long non-coding RNA XIST promotes cell growth and metastasis through regulating miR-139-5p mediated Wnt/β-catenin signaling pathway in bladder cancer

Bladder cancer is one of the most common urological malignancy all over the world. Recently, long non-coding RNA (lncRNA) XIST has been identified as an oncogenic gene in several type of cancers. However, the expression level and functional role of XIST in bladder cancer remain largely unknown. In the present study, we found that XIST was significantly up-regulated in bladder cancer tissues and cell lines, and was correlated with poor prognosis of bladder cancer patients. Furthermore, XIST knockdown significantly inhibited bladder cancer cell growth and metastasis in vitro and tumor growth in vivo. We also demonstrated that XIST acted as a competing endogenous RNA for miR-139-5p and repression of miR-139-5p could restore the inhibitory effects on bladder cancer cells induced by XIST shRNA. In addition, we identified that Wnt1 was a direct target of miR-139-5p, and XIST played the oncogenic role in bladder cancer by activating the Wnt/β-catenin signaling pathway. Taken together, our study suggested that lncRNA XIST may serve as a prognostic biomarker and a potential therapeutic target for bladder cancer.