Notch1 regulates tongue cancer cells proliferation, apoptosis and invasion

Deubiquitinase PSMD7 facilitates pancreatic cancer progression through activating Nocth1 pathway via modifying SOX2 degradation

BACKGROUND

Ubiquitination is a critical post-translational modification which can be reversed with an enzyme family known as deubiquitinating enzymes (DUBs). It has been reported that dysregulation of deubiquitination leads to carcinogenesis. As a member of the DUBs family, proteasome 26 S subunit non-ATPase 7 (PSMD7) serves as an underlying tumour-promoting factor in multiple cancers. However, the clinical significance and biological functions of PSMD7 in pancreatic cancer (PC) remain unclear.

RESULTS

In this study, we first reported frequent overexpression of PSMD7 in PC tissues, and high levels of PSMD7 were markedly linked to shorter survival and a malignant phenotype in PC patients. An array of in vitro and in vivo gain/loss-of-function tests revealed that PSMD7 facilitates the progression of PC cells. Additionally, we found that PSMD7 promotes PC cell progression by activating the Notch homolog 1 (Notch1) signalling. Interestingly, in PC cells, the inhibitory effect of PSMD7 knockdown on cellular processes was comparable to that observed upon Notch1 knockdown. Mechanistically, PSMD7 deubiquitinated and stabilised sex determining region Y (SRY)-box 2 (SOX2), a key mediator of Notch1 signalling. The stabilisation of SOX2, mediated by PSMD7, dramatically increased SOX2 protein levels, subsequently activating the Notch1 pathway. Finally, restoration of SOX2 expression abrogated the PSMD7-silenced antitumour effect.

CONCLUSIONS

Taken together, our work identifies and validates PSMD7 as a promoter of PC progression through augmentation of the Notch1 signalling pathway mediated by SOX2. This finding suggests that PSMD7 holds promise as a potential therapeutic target for the management of this refractory disease.

Regulation of the Notch signaling pathway by natural products for cancer therapy

The Notch signaling pathway is an evolutionarily conserved pathway that modulates normal biological processes involved in cellular differentiation, apoptosis, and stem cell self-renewal in a context-dependent fashion. Attributed to its pleiotropic physiological roles, both overexpression and silencing of the pathway are associated with the emergence, progression, and poorer prognosis in various types of cancer. To decrease disease incidence and promote survival, targeting Notch may have chemopreventive and anti-cancer effects. Natural products with profound historical origins have distinguished themselves from other therapies due to their easy access, high biological compatibility, low toxicity, and reliable effects at specific physiological sites in vivo. This review describes the Notch signaling pathway, particularly its normal activation process, and some main illnesses related to Notch signaling pathway dysregulation. Emphasis is placed on the effects and mechanisms of natural products targeting the Notch signaling pathway in diverse cancer types, including curcumin, ellagic acid (EA), resveratrol, genistein, epigallocatechin-3-gallate (EGCG), quercetin, and xanthohumol and so on. Existing evidence indicates that natural products are feasible solution to fight against cancer by targeting Notch signaling, either alone or in combination with current therapeutic agents.

Cytotoxic Imidazolyl-Mesalazine Ester-Based Ru(II) Complexes Reduce Expression of Stemness Genes and Induce Differentiation of Oral Squamous Cell Carcinoma

The aggressiveness and recurrence of cancer is linked to cancer stem cells (CSCs), but drugs targeting CSCs may not succeed in the clinic due to the lack of a distinct CSC subpopulation. Clinical Pt(II) drugs can increase stemness. We screened 15 RuII or IrIII complexes with mesalazine or 3-aminobenzoate Schiff bases of the general formulas [Ru(p-cym)L]+, [Ru(p-cym)L], and [Ir(Cp*)L]+ (L = L1-L9) and found three complexes (2, 12, and 13) that are active against oral squamous cell carcinoma (OSCC) CSCs. There is a putative oncogenic role of transcription factors (viz. NOTCH1, SOX2, c-MYC) to enhance the stemness. Our work shows that imidazolyl-mesalazine ester-based RuII complexes inhibit growth of CSC-enriched OSCC 3D spheroids at low micromolar doses (2 μM). Complexes 2, 12, and 13 reduce stemness gene expression and induce differentiation markers (Involucrin, CK10) in OSCC 3D cultures. The imidazolyl-mesalazine ester-based RuII complex 13 shows the strongest effect. Downregulating c-MYC suggests that RuII complexes may target c-MYC-driven cancers.

Increased NOTCH1 expression is associated with low survival in moderate/ poor differentiated human oral squamous cell carcinoma patients

Notch deregulation has been reported in various types of cancers, including Oral squamous cell carcinomas (OSCCs). The role of Notch1 signaling in oral squamous cell carcinoma (OSCC) remains poorly understood. In this study, NOTCH1 was aberrantly expressed in human oral cancer tissues compared with that in normal marginal tissues and was associated with poor prognosis. The positive Notch 1 expression was significantly associated with poor tumor differentiation status. Kaplan-Meier survival curves revealed that elevated cytoplasmic NOTCH1 expression levels in OSCC patients were associated with poor overall survival. Moreover, multivariate COX proportional hazard models revealed that T N status, AJCC stage histological grade were independent prognostic factors for survival. Our result clearly demonstrates the oncogenic role of Notch1 in oral cancer and Notch1 may be a useful biomarker to target oral cancer patients.

ZFP64 Promotes Gallbladder Cancer Progression through Recruiting HDAC1 to Activate NOTCH1 Signaling Pathway

The lack of meaningful and effective early-stage markers remains the major challenge in the diagnosis of gallbladder cancer (GBC) and a huge barrier to timely treatment. Zinc finger protein 64 (ZFP64), a member of the zinc finger protein family, is considered to be a promising predictor in multiple tumors, but its potential effect in GBC still remains unclear. Here, we identified that ZFP64 was a vital regulatory protein in GBC. We found that ZFP64 expressed higher in GBC gallbladder carcinoma tissues than in normal tissues and was positively correlated with poor prognosis. Furthermore, ZFP64 was responsible for the migration, invasion, proliferation, anti-apoptosis, and epithelial mesenchymal transition (EMT) of GBC cells in vitro and in vivo. Mechanistically, through Co-IP assay, we confirmed that ZFP64 recruits HDAC1 localized to the promoter region of NUMB for deacetylation and therefore inhibits NUMB expression. The downregulation of NUMB enhanced the activation of the Notch1 signaling pathway, which is indispensable for the GBC-promotion effect of ZFP64 on GBC. In conclusion, ZFP64 regulated GBC progression and metastasis through upregulating the Notch1 signaling pathway, and thus ZFP64 is expected to become a new focus for a GBC prognostic marker and targeted therapy.

Targeted inhibition of eIF5Ahpu suppresses tumor growth and polarization of M2-like tumor-associated macrophages in oral cancer

Eukaryotic initiation factor 5A2 (eIF5A2) is overexpressed in many types of cancer, and spermidine-mediated eIF5A hypusination (eIF5Ahpu) appears to be essential to most of eIF5A's biological functions, including its important role in regulating cancer cell proliferation, epithelial-mesenchymal transition (EMT), and cancer stem cell (CSC) properties as well as immune cell functions. Here we investigated the role of eIF5Ahpu in the growth of oral squamous cell carcinoma cells (OSCCs) and OSCC-induced polarization of M2-like tumor-associated macrophages (TAMs). TCGA dataset analysis revealed an overall upregulation in the mRNA expression of eIF5A2 and several key enzymes involved in polyamine (PA) metabolism in HNSCC, which was confirmed by Western blot and IHC studies. Blocking eIF5Ahpu by GC-7 but not the upstream key enzyme activities of PA metabolism, remarkably inhibited cell proliferation and the expression of EMT- and CSC-related genes in OSCC cells. In addition, blocking eIF5Ahpu robustly inhibited OSCC-induced M2-like TAM polarization in vitro. More Importantly, blocking eIF5Ahpu dramatically retarded tumor growth and infiltration/polarization of M2-like TAM in a syngeneic orthotopic murine tongue SCC model. Thus, eIF5Ahpu plays dual functions in regulating tumor cell growth and polarization of M2-TAMs in OSCC.

MiRNA-related metastasis in oral cancer: moving and shaking

Across the world, oral cancer is a prevalent tumor. Over the years, both its mortality and incidence have grown. Oral cancer metastasis is a complex process involving cell invasion, migration, proliferation, and egress from cancer tissue either by lymphatic vessels or blood vessels. MicroRNAs (miRNAs) are essential short non-coding RNAs, which can act either as tumor suppressors or as oncogenes to control cancer development. Cancer metastasis is a multi-step process, in which miRNAs can inhibit or stimulate metastasis at all stages, including epithelial-mesenchymal transition, migration, invasion, and colonization, by targeting critical genes in these pathways. On the other hand, long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), two different types of non-coding RNAs, can regulate cancer metastasis by affecting gene expression through cross-talk with miRNAs. We reviewed the scientific literature (Google Scholar, Scopus, and PubMed) for the period 2000-2023 to find reports concerning miRNAs and lncRNA/circRNA-miRNA-mRNA networks, which control the spread of oral cancer cells by affecting invasion, migration, and metastasis. According to these reports, miRNAs are involved in the regulation of metastasis pathways either by directly or indirectly targeting genes associated with metastasis. Moreover, circRNAs and lncRNAs can induce or suppress oral cancer metastasis by acting as competing endogenous RNAs to inhibit the effect of miRNA suppression on specific mRNAs. Overall, non-coding RNAs (especially miRNAs) could help to create innovative therapeutic methods for the control of oral cancer metastases.

Identification of NLE1/CDK1 axis as key regulator in the development and progression of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the most common pathological type of lung cancer, which is a severer threaten to human health because of its extremely high morbidity and mortality. In this study, the role of Notchless homolog 1 (NLE1) in the development of NSCLC was investigated and the underlying mechanism was explored. The outcomes showed that NLE1 expression is significantly higher in tumor tissues than normal tissues, and is correlated with the pathological stage. The regulation of NSCLC development by NLE1 was also visualized by the in vitro and in vivo loss-of-function studies, which indicated the inhibition of cell growth and migration, as well as enhancement of cell apoptosis on condition of NLE1 knockdown. As for the mechanism, it was demonstrated that NLE1 may execute its tumor-regulating function through activating E2F1-mediated transcription of CDK1, and PI3K/Akt signaling pathway was also supposed as a downstream of NLE1 in the regulation of NSCLC. Both CDK1 overexpression and treatment of Akt pathway activator could reverse the NLE1 knockdown induced NSCLC inhibition to some extent. In conclusion, this study identified NLE1 as a novel tumor promotor in the development and progression of NSCLC, which may be a potential therapeutic target in the treatment of NSCLC.

Potential Alternative Therapeutic Modalities for Management Head and Neck Squamous Cell Carcinoma: A Review

Head and neck squamous cell carcinoma (HNSCC) includes malignancies of the lip and oral cavity, oropharynx, nasopharynx, larynx, and hypopharynx. It is among the most common malignancy worldwide, affecting nearly 1 million people annually. The traditional treatment options for HNSCC include surgery, radiotherapy, and conventional chemotherapy. However, these treatment options have their specific sequelae, which produce high rates of recurrence and severe treatment-related disabilities. Recent technological advancements have led to tremendous progress in understanding tumor biology, and hence the emergence of several alternative therapeutic modalities for managing cancers (including HNSCC). These treatment options are stem cell targeted therapy, gene therapy, and immunotherapy. Therefore, this review article aims to provide an overview of these alternative treatments of HNSCC.

Advanced Squamous Cell Carcinomas of the Pelvic and Perineal Region: A Comprehensive Genomic Profiling Study

BACKGROUND

Advanced pelvic squamous cell carcinoma (pSCC) is a broad category of cancers affecting different pelvic organs and usually featuring unfavorable clinical outcomes. Thus, we aimed to assess genomic differences among pSCC cases and learn whether pSCC could potentially benefit from targeted therapies and/or immunotherapy.

MATERIALS AND METHODS

A total of 1917 advanced pSCCs, including penile (penSCC), male urethral (murthSCC), male anal (manSCC), female urethral (furthSCC), vulvar (vulSCC), cervical (crvSCC), female anal (fanSCC), and vaginal (vagSCC), underwent comprehensive genomic profiling (CGP). We used hybrid capture-based CGP to evaluate recurrent genomic alterations (GAs). Tumor mutational burden (TMB) was determined on up to 1.1 Mb of sequenced DNA and microsatellite instability (MSI) was determined on up to 95 loci. Programmed cell-death-ligand-1 (PD-L1) expression was determined by immunohistochemistry (IHC; Dako 22C3).

RESULTS

PIK3CA was the most frequently identified potentially "actionable" GA (22%-43%), followed by mTOR pathway [PTEN (0%-18%), FBXW7 (7%-29%)], and cell-cycle GAs. DNA-damage response (DDR) GAs and receptor-tyrosine kinase (RTK) targeted options were uncommon. NOTCH1 GAs were present in >15% of penSCC and vulvSCC. TMB ≥10 mut/Mb was >15% in manSCC, fanSCC, crvSCC, and vagSCC. PD-L1 high expression was >18% in all pSCC except urthSCC, manSCC, and vagSCC. HPV-16/18 detection was highest in manSCC, fanSCC, and crvSCC.

CONCLUSION

Despite similar histology, pSCCs can differ in GAs and HPV status. Overall, PIK3CA is the most frequent potentially "targetable" GA followed by mTOR and cell cycle pathway. RTK and DDR GAs are rare in pSCC. Immunotherapy could be considered for pSCC management based on TMB and PD-L1 expression.

Siah1 promotes the proliferation of NSCLC cells through ubiquitinating and stabilizing Notch1

Seven in absentia homolog 1 (Siah1) has been shown plays important roles in the pathogenesis and development of multiple cancers. However, the functions and mechanisms of Siah1 in non-small cell lung cancer (NSCLC) remain unclear. In our study, we found that knock down of Siah1 could inhibit the proliferation of NSCLC cells, while over-expression of Siah1 had the opposite effects. Molecularly, the bioinformatics analysis determined that notch receptor 1 (Notch1) might be the potential target of Siah1. Subsequently, we identified that Siah1 acted as an E3 ligase to promote the ubiquitination and stabilization of Notch1 through the proteasome pathway. Furthermore, the results showed that the Siah1 expression was directly correlated with CTR9 in human NSCLC tissues. Finally, Siah1 could promote Akt phosphorylation through regulating Notch1, thus promoting the proliferation of NSCLC cells. In conclusion, our study demonstrated that Siah1 acts as an oncogene, can ubiquitinate and stabilize Notch1 by proteasome pathway, which promotes Akt phosphorylation and ultimately leads to NSCLC cell proliferation.

Effect of Notch1 signaling on cellular proliferation and apoptosis in human laryngeal carcinoma

Background

The occurrence and development of malignancies include excessive proliferation and apoptosis resistance in tumor cells. This study aimed to identify the effects of Notch1 signaling on proliferation and apoptosis of laryngeal cancer cells in a hypoxic microenvironment.

Methods

Notch1 and Ki-67 expression in laryngeal squamous cell carcinoma (LSCC) tissues was detected by immunohistochemistry. The apoptotic index (AI) of LSCC was evaluated by the TUNEL method. Small interfering RNA (siRNA) was used to inhibit Notch1 expression in laryngeal cancer cells. Real-time PCR was used to measure Notch1, Hes1, and Hey1 mRNA expression, and Western blotting was used to measure Notch1 and Notch1 intracellular domain (N1ICD) protein expression. Annexin V-FITC/propidium iodide staining and Cell Counting Kit-8 assays were used to measure cell apoptosis and proliferation, respectively.

Results

Notch1 expression was significantly related to the proliferation index (PI) and AI in LSCC tissues. Hypoxia could induce proliferation and inhibit apoptosis in cancer cells. Notch1 expression and Notch1 signaling activity could be upregulated by hypoxia. Suppressing Notch1 signaling activity in hypoxic cells could decrease proliferation and increase apoptosis.

Conclusions

Our study has demonstrated that hypoxia may promote proliferation and inhibit apoptosis of laryngeal cancer cells. Notch1 signaling may play a pivotal role in regulating the proliferation and apoptosis resistance of laryngeal cancer cells under hypoxic conditions.

Comprehensive Integrated Single-Cell Whole Transcriptome Analysis Revealed the p-EMT Tumor Cells-CAFs Communication in Oral Squamous Cell Carcinoma

Cancer-associated fibroblasts (CAFs) and partial epithelial–mesenchymal transition (p-EMT) tumor cells are closed together and contribute to the tumor progression of oral squamous cell carcinoma (OSCC). In the present study, we deeply analyzed and integrated OSCC single-cell RNA sequencing datasets to define OSCC CAFs and p-EMT subpopulations. We highlighted the cell–cell interaction network of CAFs and p-EMT tumor cells and suggested biomarkers for the diagnosis and prognosis of OSCC during the metastasis condition. The analysis discovered four subtypes of CAFs: one p-EMT tumor cell population, and cycling tumor cells as well as TNFSF12-TNFRSF25/TNFRSF12A interactions between CAFs and p-EMT tumor cells during tumor metastasis. This suggests the prediction of therapeutically targetable checkpoint receptor–ligand interactions between CAFs and p-EMT tumor cells in OSCC regarding the metastasis status.

Signaling pathways and their potential therapeutic utility in esophageal squamous cell carcinoma

Esophageal cancer is a complex gastrointestinal malignancy with an extremely poor outcome. Approximately 80% of cases of this malignancy in Asian countries including India are of squamous cell origin, termed Esophageal Squamous Cell Carcinoma (ESCC).The five-year survival rate in ESCC patients is less than 20%. Neo-adjuvant chemo-radiotherapy (NACRT) followed by surgical resection remains the major therapeutic strategy for patients with operable ESCC. However, resistance to NACRT and local recurrence after initial treatment are the leading cause of dismal outcomes in these patients. Therefore, an alternative strategy to promote response to the therapy and reduce the post-operative disease recurrence is highly needed. At the molecular level, wide variations have been observed in tumor characteristics among different populations, nevertheless, several common molecular features have been identified which orchestrate disease progression and clinical outcome in the malignancy. Therefore, determination of candidate molecular pathways for targeted therapy remains the mainstream idea of focus in ESCC research. In this review, we have discussed the key signaling pathways associated with ESCC, i.e., Notch, Wnt, and Nrf2 pathways, and their crosstalk during disease progression. We further discuss the recent developments of novel agents to target these pathways in the context of targeted cancer therapy. In-depth research of the signaling pathways, gene signatures, and a combinatorial approach may help in discovering targeted therapy for ESCC.

ADAM12 is an independent predictor of poor prognosis in liver cancer

Disintegrin and metalloproteinase 12 (ADAM12) is thought to trigger the occurrence and development of numerous tumours, including colorectal, breast, and pancreatic cancers. On the basis of The Cancer Genome Atlas (TCGA) datasets, in this study, the relationship between ADAM12 gene expression and hepatocellular carcinoma (HCC), the prognostic value of this relationship, and the potential mechanisms influencing HCC development were evaluated. The results showed that the ADAM12 gene was significantly and highly expressed in liver cancer tissue. The high expression of the ADAM12 gene in liver cancer tissue significantly and positively correlated with T stage, pathological stage, and residual tumour. Kaplan–Meier and Cox regression analyses revealed that ADAM12 gene expression is an independent risk factor influencing the prognosis of patients with liver cancer. Pathway analyses of ADAM12 in HCC revealed ADAM12-correlated signalling pathways, and the expression level of ADAM12 was associated with immune cell infiltration. In vitro experiments demonstrated that the expression level of ADAM12 in Huh-7 and Hep3B cells was significantly higher than that in other HCC cells. ShRNA transfection experiments confirmed that the expression levels of TGF-β and Notch pathway-related proteins were significantly decreased. An EdU cell proliferation assay showed that a low level of ADAM12 gene expression significantly inhibited the proliferative activity of HCC cells. Cell cycle experiments showed that low ADAM12 expression blocked the G1/S phase transition. Overall, this research revealed that high ADAM12 gene expression implies a poor prognosis for patients with primary liver cancer. In addition, it is a potential indicator for the diagnosis of liver cancer.

Molecular mechanism of albumin in suppressing invasion and metastasis of hepatocellular carcinoma

BACKGROUND & AIMS

Worldwide, hepatocellular carcinoma (HCC) is one of the most common causes of death in people. Albumin (ALB) is considered as an important indicator for HCC prognosis, and evidence has shown HCC cell growth can be regulated by ALB. However, the role of ALB in hepatocarcinogenesis and the mechanism of action is still unknown.

METHODS

The expression of ALB was determined by clinical profiles, immunohistochemistry, and western blot. Wound healing and Transwell assays were conducted to evaluate the effects of ALB during migration and invasion in HCC. We used mass spectrometry coupled isobaric tags for relative and absolute quantitation (iTRAQ)-technology to identify secretory differentially expressed proteins (DEPs) in ALB knockdown HepG2 cells. Western blot, reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay techniques were used for verification.

RESULTS

We suggested that ALB was associated with aggressive metastasis and depleting ALB significantly promoted invasion and migration of HCC. A total of 210 DEPs were identified after silencing of ALB. We observed that a negative correlation between ALB and urokinase plasminogen activator surface receptor (uPAR) expression levels.

CONCLUSIONS

ALB acts as a tumour suppressor and plays a key role in HCC progression, particularly in invasion and metastasis. Suppression of ALB promoted migration and invasion of HCC cells by increasing uPAR, matrix metalloproteinase (MMP2), and MMP9.

SNHG1/miR-194-5p/MTFR1 Axis Promotes TGFβ1-Induced EMT, Migration and Invasion of Tongue Squamous Cell Carcinoma Cells

Tongue squamous cell carcinoma (TSCC) is a common malignancy with aggressive biological behaviors. Mitochondrial fission regulator 1 (MTFR1), is aberrantly expressed in head and neck squamous cell carcinoma (HNSC), but its role in TSCC remains unclear. We aimed to explore the role of MTFR1 in TSCC. The expression of long non-coding RNA small nucleolar RNA host gene 1 (SNHG1), microRNA-194-5p and MTFR1 in TSCC cells was measured by RT-qPCR. Luciferase reporter assay and RNA pull down assay were applied to confirm the binding capacity between miR-194-5p and SNHG1 (or MTFR1). TSCC cell invasion and migration were accessed by Transwell assays. The protein levels of MTFR1 and epithelial-mesenchymal transition (EMT) markers were examined by western blot. MTFR1 had high expression level in TSCC. MTFR1 knockdown inhibited transforming growth factor β1 (TGFβ1)-induced EMT, migration and invasion of TSCC cells in vitro. MiR-194-5p targeted MTFR1 and negatively regulated its expression. In addition, SNHG1 upregulated the expression of MTFR1 by binding with miR-194-5p. Importantly, SNHG1 promoted EMT, invasion and migration of TSCC cells by upregulating MTFR1. SNHG1/miR-194-5p/MTFR1 axis promotes TGFβ1-induced EMT, migration and invasion of cells in TSCC, which could be potential targets for treating TSCC patients.

A2B5-positive oligodendrocyte precursor cell transplantation improves neurological deficits in rats following spinal cord contusion associated with changes in expression of factors involved in the Notch signaling pathway

BACKGROUND

Oligodendrocyte precursor cells (OPCs) are myelinated glial cells of the central nervous system (CNS), able to regenerate oligodendrocytes and myelin. This study aimed to elucidate the effect of A2B5-positive (A2B5+) OPC transplantation in rats with spinal cord contusion (SCC) and to investigate changes in expression of various factors involved in the Notch signaling pathway after OPC transplantation.

METHODS

OPCs were obtained from induced pluripotent stem cells (iPSCs) originating from mouse embryo fibroblasts (MEFs). After identification of iPSCs and iPSC-derived OPCs, A2B5+ OPCs were transplanted into the injured site of rats with SCC one week after SCC insult. Behavioral tests evaluated motor and sensory function 7 days after OPC transplantation. Real-time quantitative polymerase chain reaction (RT-qPCR) determined the expression of various cytokines related to the Notch signaling pathway after OPC transplantation.

RESULTS

IPSC-derived OPCs were successfully generated from MEFs, as indicated by positive immunostaining of A2B5, PDGFα and NG2. Further differentiation of OPCs was identified by immunostaining of Olig2, Sox10, Nkx2.2, O4, MBP and GFAP. Importantly, myelin formation was significantly enhanced in the SCC+ OPC group and SCI-induced motor and sensory dysfunction was largely alleviated by A2B5+ OPC transplantation. Expression of factors involved in the Notch signaling pathway (Notch-1, Numb, SHARP1 and NEDD4) was significantly increased after OPC transplantation.

CONCLUSIONS

A2B5+ OPC transplantation attenuates motor and sensory dysfunction in SCC rats by promoting myelin formation, which may be associated with change in expression of factors involved in the Notch signaling pathway.

CAMSAP1 Mutation Correlates With Improved Prognosis in Small Cell Lung Cancer Patients Treated With Platinum-Based Chemotherapy

Platinum-based chemotherapy is the first-line treatment for small cell lung cancer (SCLC). However, due to patients developing a resistance to the drug, most experience relapse and their cancer can become untreatable. A large number of recent studies have found that platinum drug sensitivity of various cancers is affected by specific gene mutations, and so with this study, we attempted to find an effective genetic biomarker in SCLC patients that indicates their sensitivity to platinum-based drugs. To do this, we first analyzed whole exome sequencing (WES) and clinical data from two cohorts to find gene mutations related to the prognosis and to the platinum drug sensitivity of SCLC patients. The cohorts used were the Zhujiang cohort (N = 138) and the cohort reported by George et al. (N = 101). We then carried out gene set variation analysis (GSVA) and gene set enrichment analysis (GSEA) to investigate possible molecular mechanisms through which these gene mutations affect patient prognosis and platinum drug sensitivity. We found that for SCLC patients, CAMSAP1 mutation can activate anti-tumor immunity, mediate tumor cell apoptosis, inhibit epithelial-mesenchymal transition (EMT), improve prognosis, and improve platinum drug sensitivity, suggesting that CAMSAP1 mutation may be a potential biomarker indicating platinum drug sensitivity and patient prognosis in SCLC.

Enabled homolog (ENAH) regulated by RNA binding protein splicing factor 3b subunit 4 (SF3B4) exacerbates the proliferation, invasion and migration of hepatocellular carcinoma cells via Notch signaling pathway

Enabled homolog (ENAH) is an actin-binding protein that implicated in multiple malignant tumors. High ENAH expression has been verified to be associated with poor prognosis in hepatocellular carcinoma (HCC). We aimed to reveal the role of ENAH in HCC and the potential mechanism. ENAH expression in HCC tissues and the prognostic correlation were analyzed by GEPIA2 database. RT-qPCR and Western blot were used to test ENAH expression in HCC cells. Following ENAH silencing, cell proliferation was estimated by CCK-8 and colony formation assays. Transwell and wound healing assays were to assess cell invasion and migration. ENCORI database was to analyze the correlation between ENAH and splicing factor 3b subunit 4 (SF3B4) in HCC tissues, which was then verified by RIP and actinomycin D assay. Then, the expression of Notch signaling-related proteins was detected by Western blotting after ENAH knockdown. Afterward, Notch1 was overexpressed to validate whether ENAH impacted the biological events of HCC cells through mediating Notch signaling. Results revealed that ENAH expression was elevated in HCC tissues and cells and associated with poor prognosis. ENAH deficiency mitigated proliferation, invasion and migration of HCC cells. Mechanistically, ENAH was positively correlated with SF3B4 in HCC tissues. SF3B4 could bind to ENAH mRNA and stabilized ENAH. Besides, ENAH activated Notch signaling. Notch1 up-regulation reversed the influence of ENAH knockdown on biological events of HCC cells. Collectively, ENAH regulated by SF3B4 promoted the development of HCC through activating Notch signaling, which identified ENAH as a potent molecular target for HCC therapy and prognosis.

Shooting at Moving and Hidden Targets-Tumour Cell Plasticity and the Notch Signalling Pathway in Head and Neck Squamous Cell Carcinomas

Head and Neck Squamous Cell Carcinoma (HNSCC) is often aggressive, with poor response to current therapies in approximately 40-50% of the patients. Current therapies are restricted to operation and irradiation, often combined with a small number of standard-of-care chemotherapeutic drugs, preferentially for advanced tumour patients. Only very recently, newer targeted therapies have entered the clinics, including Cetuximab, which targets the EGF receptor (EGFR), and several immune checkpoint inhibitors targeting the immune receptor PD-1 and its ligand PD-L1. HNSCC tumour tissues are characterized by a high degree of intra-tumour heterogeneity (ITH), and non-genetic alterations that may affect both non-transformed cells, such as cancer-associated fibroblasts (CAFs), and transformed carcinoma cells. This very high degree of heterogeneity likely contributes to acquired drug resistance, tumour dormancy, relapse, and distant or lymph node metastasis. ITH, in turn, is likely promoted by pronounced tumour cell plasticity, which manifests in highly dynamic and reversible phenomena such as of partial or hybrid forms of epithelial-to-mesenchymal transition (EMT), and enhanced tumour stemness. Stemness and tumour cell plasticity are strongly promoted by Notch signalling, which remains poorly understood especially in HNSCC. Here, we aim to elucidate how Notch signal may act both as a tumour suppressor and proto-oncogenic, probably during different stages of tumour cell initiation and progression. Notch signalling also interacts with numerous other signalling pathways, that may also have a decisive impact on tumour cell plasticity, acquired radio/chemoresistance, and metastatic progression of HNSCC. We outline the current stage of research related to Notch signalling, and how this pathway may be intricately interconnected with other, druggable targets and signalling mechanisms in HNSCC.

Variances in the Expression of mRNAs and miRNAs Related to the Histaminergic System in Endometrioid Endometrial Cancer

Research has indicated higher concentrations of histamine and polyamine in endometrioid tissue in comparison with healthy tissue. The aim of this study was to evaluate changes in the expression patterns of messenger RNA (mRNAs) and microRNA (miRNAs) related to the histaminergic system in endometrial samples and whole blood in women with endometrioid endometrial cancer. The study group consisted of 30 women with endometrioid endometrial cancer qualified for hysterectomy (G1 well-differentiated, 15 cases; G2 moderately differentiated, 8 cases; and G3 poorly differentiated, 7 cases). The control group included 30 women with no neoplastic changes during routine gynecological examinations. The molecular analysis consisted of the microarray analysis of mRNAs and miRNAs related to the histaminergic system, reverse-transcription quantitative polymerase chain reaction (RTqPCR), and enzyme-linked immunosorbent assay (ELISA). Out of 65 mRNAs connected with the histaminergic system, 10 differentiate the samples of tissue and blood obtained from patients with endometrioid endometrial cancer in comparison with the control group (p < 0.05). mRNA histamine receptor 1,3 (HRH1, HRH3), and solute carrier family 22 member 3 (SLC23A2) differentiating samples of endometrioid endometrial cancer independent of either G or control. The highest probability of interaction, based on the target score miRDB, between the selected miRNAs and mRNAs was found for the hybrids hsa-miR-1-3p and endothelin 1 (END1), hsa-miR-27a-5β and SLC23A2. The selected mRNA and miRNA transcripts seem to be promising for molecularly targeted therapies in the context of endometrioid endometrial cancer.

Notch signaling in oral pre-cancer and oral cancer

Notch signaling involves cell to cell contact. It is an ancient signaling mechanism that is conserved throughout the animal kingdom. The basic function of Notch signaling is to decide cell fate and execute asymmetrical division. Notch signaling is indispensable for embryo growth. Aberrant Notch signaling involves in cancer progression by altering cell proliferation rate, tumor micro-environment, stem cell activities. The role of Notch signaling in cancer progression is context-dependent. In breast cancer and T cell lymphoma Notch signaling is highly active, whereas in squamous cell carcinoma (SCC) as oral and skin cancer, the signaling is suppressed. It is believed that in SCC, Notch-mediated tumor growth is due to the cell non-autonomous function. Oral cancer is the 6th most risky cancer worldwide. In many patients, oral cancer is preceded by pre-cancer conditions. In this review, we have summarized the research knowledge related to the role of Notch signaling in oral cancer and pre-cancer conditions and the therapeutic options available targeting different components of Notch pathways.

EGCG inhibits growth of tumoral lesions on lip and tongue of K-Ras transgenic mice through the Notch pathway

Epigallocatechin-3-gallate (EGCG), the main active ingredient of green tea, exhibits low toxic side effect and versatile bioactivities, and its anti-cancer effect has been extensively studied. Most of the studies used cancer cell lines and xenograft models. However, whether EGCG can prevent tumor onset after cancer-associated mutations occur is still controversial. In the present study, Krt14-cre/ERT-Kras transgenic mice were developed and the expression of K-RasG12D was induced by tamoxifen. Two weeks after induction, the K-Ras mutant mice developed exophytic tumoral lesions on the lips and tongues, with significant activation of Notch signaling pathway. Administration of EGCG effectively delayed the time of appearance, decreased the size and weight of tumoral lesions, relieved heterotypic hyperplasia of tumoral lesions, and prolonged the life of the mice. The Notch signaling pathway was significantly inhibited by EGCG in the tumoral lesions. Furthermore, EGCG significantly induced cell apoptosis and inhibited the proliferation of tongue cancer cells by blocking the activation of Notch signaling pathway. Taken together, these results indicate EGCG as an effective chemotherapeutic agent for tongue cancer by targeting Notch pathway.

Long-non-coding RNA RUSC1-AS1 accelerates osteosarcoma development by miR-101-3p-mediated Notch1 signalling pathway

Background

Long non-coding RNA (lncRNA) RUSC1-AS1 has been found to modulate several cancers development. In this study, we explored the role of RUSC1-AS1 on osteosarcoma (OS) progression.

Methods

Quantitative Real-time PCR (qRT-PCR) was conducted to test the relative expression of RUSC1-AS1, Notch1 mRNA and miR-101-3p in OS tissues and adjacent normal tissues. Gain- or loss- of functional assays were carried out to determine the roles of RUSC1-AS1 and miR-101-3p in OS progression both in vitro and in vivo. The expression of E-cadherin, N-cadherin, Vimentin, Snail, Notch1, Ras and ERK was determined by Western blot. Furthermore, the relationships between RUSC1-AS1 and miR-101-3p, Notch1 and miR-101-3p were confirmed through RNA immunoprecipitation (RIP) and dual luciferase reporter gene assay.

Results

RUSC1-AS1 and Notch1 were up-regulated in OS cells and tissues. Down-regulating RUSC1-AS1 significantly attenuated the proliferative, epithelial-mesenchymal transition (EMT), growth, lung metastasis, migrative and invasive abilities of MG-63 and Saos-2 cells, and aggravated apoptosis, accompanied with down-regulated Notch1-Ras-ERK1/2 in those cells both in vitro and in vivo, while overexpression of RUSC1-AS1 exerted opposite effects. Overexpressing miR-101-3p in OS cells had similar effects as RUSC1-AS1 inhibition. In addition, RUSC1-AS1 functioned as a competing endogenous RNA (ceRNA) to competitively sponge miR-101-3p, thus upregulating Notch1 expression and mediating the malignant behaviors of OS cells.

Conclusion

RUSC1-AS1 is a novel oncogenic lncRNA in OS through the miR-101-3p-Notch1-Ras-ERK pathway, which might be a potential therapeutic target for OS.

CDH11 Regulates Adhesion and Transcellular Migration of Tongue Squamous Cell Carcinoma

Purpose

CDH11, as a member of cadherins, mediates homotypic cell adhesion. Some studies have shown that CDH11 plays an important role in the development of tumors, especially in the processes of tumor invasion and metastasis. While features of CDH11 in tongue squamous cell carcinoma (TSCC) are still indeterminate, the purpose of the present study is to explore the role of CDH11 in TSCC.

Methods

The expression of cadherin gene in a TSCC cell line with high metastatic potential (LN4) and the parental CAL27 were examined both in the TCGA database and in collected clinical samples, further verified by quantitative real-time PCR. The effects of CDH11 on the proliferation, apoptosis, migration, invasion and adhesion were tested in appropriate ways after CDH11 was overexpressed in TSCC cells.

Results

Among the 22 cadherin genes, CDH11 was one of the most obviously inhibited genes in LN4 cells as compared with the parental cells. Overexpression of CDH11 did not show a significant effect on cell proliferation, apoptosis, stemness, migration and invasion ability of TSCC cells themselves, but it increased the adhesion of TSCC cells with human oral epithelial cells and decreased their ability to pass through human oral epithelial cells (HOECs) for migration.

Conclusion

The results indicated that CDH11 plays as a tumor suppressor in tongue squamous cell carcinoma by inhibiting the invasion and migration of tongue cancer cells. CDH11 may serve as an effective clinical target for new tongue cancer treatments.

DLX5 promotes osteosarcoma progression via activation of the NOTCH signaling pathway

The distal-less (dlx) homeobox transcription factors have been implicated roles in bone development. DLX5, in particular, was shown to play essential roles in osteoblast differentiation by targeting RUNX2, a master transcription factor for bone development. Interestingly, DLX5 has also been shown to play an oncogenic role in lung and other cancers, possibly via regulation of MYC expression. Given its dual roles in bone and cancer, this study aimed to investigate the effect of DLX5 on progression of osteosarcoma (OS), the primary bone cancer that is characterized by abnormal bone formation and osteoblast activity. Expression of DLX5 in OS cell lines was detected by quantitative real-time PCR (qRT-PCR) and western blot (WB). In vitro and in vivo assays were performed to investigate the oncogenic function of DLX5 in OS cells and xenograft models. Luciferase reporter assay was performed to determine the underlying mechanism of DLX5-mediated OS aggressiveness. The results showed that DLX5 was differentially expressed in OS cell lines, with significantly upregulated levels in HOS and MG-63 and relatively low levels in U2OS and 143B cell lines, compared with the normal bone cell line. DLX5 knockdown in HOS and MG-63 cell lines by siRNA inhibited OS cell growth and progression, and induced cell apoptosis and cell cycle changes both in vitro and in vivo. Meanwhile, DLX5 overexpression had the opposite effect on U2OS and 143B cell lines. Notably, a positive correlation between the expression patterns of NOTCH1 and DLX5 was also observed. The expression levels of NICD (NOTCH1 intracellular domain) and HES1 (classical target of NOTCH) were closely associated with DLX5 expression. Whereas knockdown of DLX5 in OS cells resulted in decreased expression of NOTCH1 and reduced cell proliferation and migration, which were rescued by overexpression of NOTCH1. We further analyzed DLX5 and NOTCH1 genes using JASPAR software and found two potential DLX5 binding sites within the NOTCH1 promoter. Dual-luciferase assay demonstrated that DLX5 specifically activates the NOTCH1 promoter and controls its expression. Taken together, our results support that DLX5 plays an oncogenic role in OS development, which can at least partially, be attributed to activation of the NOTCH signaling pathway.

Molecular Landscape of the Epithelial-Mesenchymal Transition in Endometrioid Endometrial Cancer

Modern diagnostics are based on molecular analysis and have been focused on searching for new molecular markers to use in diagnostics. Included in this has been the search for the correlation between gene expression in tissue samples and liquid biological materials. The aim of this study was to evaluate the differences in the expression profile of messenger RNA (mRNA) and micro-RNA (miRNA) related to the epithelial-mesenchymal transition (EMT) in different grades of endometrial cancer (G1-G3), in order to select the most promising molecular markers. The study material consisted of tissue samples and whole blood collected from 30 patients with endometrial cancer (study group; G1 = 15; G2 = 8; G3 = 7) and 30 without neoplastic changes (control group). The molecular analysis included the use of the microarray technique and RTqPCR. Microarray analysis indicated the following number of mRNA differentiating the endometrial cancer samples from the control (tissue/blood): G1 vs. C = 21/18 mRNAs, G2 vs. C = 19/14 mRNAs, and G3 vs. C = 10/9 mRNAs. The common genes for the tissue and blood samples (Fold Change; FC > 3.0) were G1 vs. C: TGFB1, WNT5A, TGFB2, and NOTCH1; G2 vs. C: BCL2L, SOX9, BAMBI, and SMAD4; G3 vs. C STAT1 and TGFB1. In addition, mRNA TGFB1, NOTCH1, and BCL2L are common for all grades of endometrial cancer. The analysis showed that miR-144, miR-106a, and miR-30d are most strongly associated with EMT, making them potential diagnostic markers.

Up-regulation of miR-34c-5p inhibits nasopharyngeal carcinoma cells by mediating NOTCH1.Biosci Rep. 2020;40. [PMID: 32458967 DOI: 10.1042/BSR20200302]

OBJECTIVE

To explore the correlation between miR-34c-5p and NOTCH1 in nasopharyngeal carcinoma (NPC).

MATERIALS AND METHODS

qPCR was employed to quantify miR-34c-5p and NOTCH1 mRNA in NPC, and Western blot to detect NOTCH1. MiR-34c-5p mimics/inhibitor and NOTCH1 siRNA were constructed to analyze the role of miR-34c-5p/NOTCH1 on the biological function of NPC cells.

RESULTS

NPC cells showed lower miR-34c-5p expression and higher NOTCH1 expression than normal cells, and up-regulating miR-34c-5p or inhibiting NOTCH1 could strongly suppress the epithelial-mesenchymal transition (EMT), proliferation, invasion and migration of NPC cells, and induce apoptosis in them. Up-regulating miR-34c-5p could inhibit NOTCH1, and miR-34c-5p was negatively correlated with NOTCH1. Rescue experiment results revealed that NOTCH1 up-regulation could counteract the changes of cell process induced by increased miR-34c-5p.

CONCLUSION

MiR-34c-5p inhibits the growth of NPC by down-regulating NOTCH1, so up-regulating miR-34c-5p or down-regulating NOTCH1 may become the potential direction of NPC treatment.

The Important Role of N6-methyladenosine RNA Modification in Non-Small Cell Lung Cancer

N6-methyladenosine (m⁶A) is one of the most prevalent epigenetic modifications of eukaryotic RNA. The m⁶A modification is a dynamic and reversible process, regulated by three kinds of regulator, including m⁶A methyltransferases, demethylases and m⁶A-binding proteins, and this modification plays a vital role in many diseases, especially in cancers. Accumulated evidence has proven that this modification has a significant effect on cellular biological functions and cancer progression; however, little is known about the effects of the m⁶A modification in non-small cell lung cancer (NSCLC). In this review, we summarized how various m⁶A regulators modulate m⁶A RNA metabolism and demonstrated the effect of m⁶A modification on the progression and cellular biological functions of NSCLC. We also discussed how m⁶A modification affects the treatment, drug resistance, diagnosis and prognosis of NSCLC patients.

Statistical and bioinformatic analysis of hemimethylation patterns in non-small cell lung cancer

Background

DNA methylation is an epigenetic event involving the addition of a methyl-group to a cytosine-guanine base pair (i.e., CpG site). It is associated with different cancers. Our research focuses on studying non-small cell lung cancer hemimethylation, which refers to methylation occurring on only one of the two DNA strands. Many studies often assume that methylation occurs on both DNA strands at a CpG site. However, recent publications show the existence of hemimethylation and its significant impact. Therefore, it is important to identify cancer hemimethylation patterns.

Methods

In this paper, we use the Wilcoxon signed rank test to identify hemimethylated CpG sites based on publicly available non-small cell lung cancer methylation sequencing data. We then identify two types of hemimethylated CpG clusters, regular and polarity clusters, and genes with large numbers of hemimethylated sites. Highly hemimethylated genes are then studied for their biological interactions using available bioinformatics tools.

Results

In this paper, we have conducted the first-ever investigation of hemimethylation in lung cancer. Our results show that hemimethylation does exist in lung cells either as singletons or clusters. Most clusters contain only two or three CpG sites. Polarity clusters are much shorter than regular clusters and appear less frequently. The majority of clusters found in tumor samples have no overlap with clusters found in normal samples, and vice versa. Several genes that are known to be associated with cancer are hemimethylated differently between the cancerous and normal samples. Furthermore, highly hemimethylated genes exhibit many different interactions with other genes that may be associated with cancer. Hemimethylation has diverse patterns and frequencies that are comparable between normal and tumorous cells. Therefore, hemimethylation may be related to both normal and tumor cell development.

Conclusions

Our research has identified CpG clusters and genes that are hemimethylated in normal and lung tumor samples. Due to the potential impact of hemimethylation on gene expression and cell function, these clusters and genes may be important to advance our understanding of the development and progression of non-small cell lung cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07990-7.

Prognostic Implications of ALDH1 and Notch1 in Different Subtypes of Oral Cancer

Background

The present study aimed to investigate the clinical significance and prognostic value of the immunoexpression of cancer stem cell markers, ALDH1 and Notch1, in subtypes of oral squamous cell carcinoma.

Materials and Methods

The expression of ALDH1 and Notch1 in 63 patients with well and poorly differentiated oral squamous cell carcinomas and their subtypes, verrucous carcinoma and basaloid squamous cell carcinoma, was evaluated by immunohistochemistry. The semi-quantitative analysis of the ALDH1 and Notch immunoexpression levels, based on the capture of 10 microscopic fields, at 400X magnification, at the invasive tumor front was performed and associated with clinicopathological variables using the chi-square test or Fisher's exact test. The overall and disease-free survival rates were estimated according to the Kaplan-Meier method and the curves were compared using the log-rank test. The independent effects of variables were calculated using Cox's proportional hazards regression model.

Results

Strong ALDH1 and Notch1 expression was observed in 16 (25.4%) and 27 (42.9%) oral squamous cell carcinomas including their subtypes, respectively. Most tumors with strong immunoexpression of ALDH1 were basaloid squamous cell carcinoma (56.3%). Statistically significant associations were observed between the strong immunoexpression of Notch1 in poorly differentiated oral squamous cell carcinoma with perineural infiltration (p = 0.011) and lymph node involvement (pN+) (p = 0.034). The strong immunoexpression of ALDH1 was a prognostic factor associated with worse overall survival (p = 0.040) for patients with oral cancer.

Conclusion

The strong immunoexpression of Notch1 can contribute to identification of patients with poorly differentiated oral squamous cell carcinoma, who have perineural infiltration or lymph node metastasis. In addition, the strong immunoexpression of ALDH1 may help to identify a worse prognosis in patients with oral squamous cell carcinoma and their subtypes.

High expression of Notch2 drives tongue squamous cell carcinoma carcinogenesis

Tongue squamous cell carcinoma (TSCC) is one of the most common cancers in the oral cavity. Notch signaling is frequently dysregulated in cancer. However, the role of Notch2 in TSCC is not well understood. The aim of this study was to investigate the effect of abnormal expression of Notch2 in TSCC. The expression of Notch2 was tested in 47 pairs of tissues from tongue cancer and normal samples by using immunohistochemical staining. Tongue cancer cells were transfected with siRNA or plasmid. The proliferation of the cells was tested by the CCK8 assay and colony formation assay. Subcutaneous tumor model was established to observe tumor growth. Transwell assay was used to detect the changes of cell migration and invasion ability. A humanized anti-Notch2 antibody was used to TSCC cells. We found that Notch2 was upregulated in tongue carcinoma tissues. Knocking down the expression of Notch2 by siRNA in the TSCC cell lines decreased proliferation ability both in vitro and in vivo. In addition, migration and invasion abilities were inhibited by knockdown of Notch2 in the TSCC cells. However, overexpression of Notch2 increased tongue cancer cell proliferation, invasion and migration. The humanized anti-Notch2 antibody inhibited TSCC cell growth. The results indicated that Notch2 is an oncogene in tongue squamous cell carcinoma and may become the target of a new approach for treating TSCC.

MiR-21 mediates the protection of kaempferol against hypoxia/reoxygenation-induced cardiomyocyte injury via promoting Notch1/PTEN/AKT signaling pathway

Kaempferol, a natural flavonoid compound, possesses potent myocardial protective property in ischemia/reperfusion (I/R), but the underlying mechanism is not well understood. The present study was aimed to explore whether miR-21 contributes to the cardioprotective effect of kaempferol on hypoxia/reoxygenation (H/R)-induced H9c2 cell injury via regulating Notch/phosphatase and tensin homologue (PTEN)/Akt signaling pathway. Results revealed that kaempferol obviously attenuates H/R-induced the damages of H9c2 cells as evidence by the up-regulation of cell viability, the down-regulation of lactate dehydrogenase (LDH) activity, the reduction of apoptosis rate and pro-apoptotic protein (Bax) expression, and the increases of anti-apoptotic protein (Bcl-2) expression. In addition, kaempferol enhanced miR-21 level in H9c2 cells exposed to H/R, and inhibition of miR-21 induced by transfection with miR-21 inhibitor significantly blocked the protection of kaempferol against H/R-induced H9c2 cell injury. Furthermore, kaempferol eliminated H/R-induced oxidative stress and inflammatory response as illustrated by the decreases in reactive oxygen species generation and malondialdehyde content, the increases in antioxidant enzyme superoxide dismutase and glutathione peroxidase activities, the decreases in pro-inflammatory cytokines interleukin (IL)-1β, IL-8 and tumor necrosis factor-alpha levels, and an increase in anti-inflammatory cytokine IL-10 level, while these effects of kaempferol were all reversed by miR-21 inhibitor. Moreover, results elicited that kaempferol remarkably blocks H/R-induced the down-regulation of Notch1 expression, the up-regulation of PTEN expression, and the reduction of P-Akt/Akt, indicating that kaempferol promotes Notch1/PTEN/AKT signaling pathway, and knockdown of Notch1/PTEN/AKT signaling pathway induced by Notch1 siRNA also abolished the protection of kaempferol against H/R-induced the damage of H9c2 cells. Notably, miR-21 inhibitor alleviated the promotion of kaempferol on Notch/PTEN/Akt signaling pathways in H9c2 cells exposed to H/R. Taken together, these above findings suggested thatmiR-21 mediates the protection of kaempferol against H/R-induced H9c2 cell injuryvia promoting Notch/PTEN/Akt signaling pathway.

GPR50 Promotes Hepatocellular Carcinoma Progression via the Notch Signaling Pathway through Direct Interaction with ADAM17

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide, and it is thus critical to identify novel molecular biomarkers of HCC prognosis and elucidate the molecular mechanisms underlying HCC progression. Here, we show that G-protein-coupled receptor 50 (GPR50) in HCC is overexpressed and that GPR50 knockdown may downregulate cancer cell progression through attenuation of the Notch signaling pathway. GPR50 knockdown was found to reduce HCC progression by inactivating Notch signaling in a ligand-independent manner through a disintegrin and metalloproteinase metallopeptidase domain 17 (ADAM17), a proteolytic enzyme that cleaves the Notch receptor, which was corroborated by GPR50 overexpression in hepatocytes. GPR50 silencing also downregulated transcription and translation of ADAM17 through the AKT/specificity protein-1 (SP1) signaling axis. Notably, GPR50 was found to directly interact with ADAM17. Overall, we demonstrate a novel GPR50-mediated regulation of the ADAM17-Notch signaling pathway, which can provide insights into HCC progression and prognosis and development of Notch-based HCC treatment strategies.

A Review on Notch Signaling and Colorectal Cancer

Colorectal cancer (CRC) has one of the highest mortality rates despite the advancement of treatment options. Aggressive CRC remains difficult to treat owing to the activation of oncogenic signaling pathways such as the Notch signaling pathway. The role of Notch receptors varies according to the difference in their structures; in particular, aberrant activation of Notch1 has been attributed to the severity of CRC. Notch1 activation in CRC is inhibited by small molecule inhibitors that target γ-secretase, an enzyme responsible for the third and last cleavage step of Notch receptors. γ-Secretase also produces the intracellular domain that finally carries out cellular functions by activating downstream effectors. However, most inhibitors block γ-secretase non-selectively and cause severe toxicity. Plant-source-derived small molecules, monoclonal antibodies, biological molecules (such as SiRNAs), and compounds targeting the Notch1 receptor itself or the downstream molecules such as HES1 are some of the options that are in advanced stages of clinical trials. The Negative Regulatory Region (NRR), which plays a central role in the transduction of Notch1 signaling in the event of ligand-dependent and ligand-independent Notch1 processing is also being targeted specifically by monoclonal antibodies (mAbs) to prevent aberrant Notch1 activation. In this review, we discuss the role of Notch1 in CRC, particularly its metastatic phenotype, and how mutations in Notch1, specifically in its NRR region, contribute to the aberrant activation of Notch1 signaling, which, in turn, contributes to CRC pathogenesis. We also discuss prevailing and emerging therapies that target the Notch1 receptor and the NRR region, and we highlight the potential of these therapies in abrogating Notch signaling and, thus, CRC development and progression.

Role of HSP27 in the multidrug sensitivity and resistance of colon cancer cells

Multidrug resistance in cancer cells is a primary factor affecting therapeutic efficacy. Heat shock 27 kD protein 1 (HSP27) is associated with cell apoptosis and resistance to chemotherapy. However, the mechanisms underlying HSP27-associated pathways in colon cancer cells remain unclear. Therefore, the present study used short hairpin (sh) RNA to inhibit HSP27 expression in colon cancer cells in order to investigate the effects in vitro and in vivo. Flow cytometry was used to investigate cell apoptosis and a xenograft model was employed to examine the tumorigenesis. Protein expression was measured by Western blotting. The results revealed that suppression of HSP27 expression significantly increased cell apoptosis, inhibited tumor growth and enhanced sensitivity to the anti-cancer agents 5-fluorouracil (5-FU) and vincristine (VCR). shHSP27 significantly decreased the expression of notch receptor 1 and the phosphorylation level of Akt and mTOR, and enhanced the effect of 5-FU and VCR. In conclusion, HSP27 suppression enhanced the sensitivity of colon cancer cells to 5-FU and VCR, and increased colon cancer cell apoptosis with and without chemotherapy. Therefore, the development of novel therapeutic agents that inhibit the expression of HSP27 may offer a new treatment option for colon cancer.

FLI-06 Intercepts Notch Signaling And Suppresses The Proliferation And Self-renewal Of Tongue Cancer Cells

Purpose

The Notch signaling pathway plays an oncogenic role in tongue squamous cell carcinoma. The aim of this study was to inhibit the proliferation and self-renewal of tongue cancer cells by applying Notch signaling pathway inhibitor FLI-06 (Selleck, USA) and to lay a foundation for the clinically targeted treatment of tongue cancer for the future.

Methods

The mRNA expression level of Notch1 and the overall survival rate of patients with tongue cancer were examined by analyzing the TCGA database. Tongue cancer cells were treated with FLI-06. Cell proliferation, apoptosis, and stem cell self-renewal ability were tested in appropriate ways. A xenograft mouse model was established to observe tumor growth.

Results

From the TCGA data, we demonstrated that patients with high expression of Notch1 had a poor prognosis. We observed that the Notch signaling pathway inhibitor FLI-06 can restrain the activation of the Notch signaling pathway, decrease cell proliferation and induce cell apoptosis in vitro. The xenograft experiment indicated that intraperitoneal injection of FLI-06 inhibited tumor growth and increased cell apoptosis. FLI-06 suppressed both the mRNA and protein expression of Notch receptor and Notch targeted genes. We also observed that FLI-06 suppressed the proliferation of tongue cancer stem cells.

Conclusion

FLI-06 can block the proliferation and self-renewal of tongue cancer cells. It is inferred that this compound, which inhibits the Notch signaling pathway, may serve as a potential targeted drug for the treatment of tongue cancer in the clinic.

FZD2 regulates cell proliferation and invasion in tongue squamous cell carcinoma

Many studies have shown that FZD2 is significantly associated with tumor development and tumor metastasis. The purpose of the present study was to gain insight into the role of FZD2 in the cell proliferation and invasion of tongue squamous cell carcinoma. According to TCGA-HNSC dataset, among the 10 Frizzled receptors, FZD2 exhibited the highest degree of differential expression between cancer tissues and normal tissues, and the overall survival of patients with higher FZD2 levels was shown to be significantly shorter compared with those with lower FZD2 levels. The upregulation of FZD2 in clinical tongue cancer tissues was validated by real-time PCR. Knockdown of FZD2 inhibited the proliferation, migration and invasion of CAL-27 and TCA-8113 cells, whereas overexpression of FZD2 led to the opposite results. Further analysis revealed that FZD2 is positively correlated with WNT3A, WNT5B, WNT7A and WNT2 and is negatively correlated with WNT4. These results indicated that FZD2 may act as an oncogene in tongue squamous cell carcinoma. Therefore, FZD2 may be a target for the diagnosis, prognosis and gene therapy of tongue cancer.

MicroRNA‑495 targets Notch1 to prohibit cell proliferation and invasion in oral squamous cell carcinoma

MicroRNAs (miRNAs) are associated with the initiation and progression of oral squamous cell carcinoma (OSCC) by regulating a variety of cancer‑associated behaviors. Fully understanding the regulatory mechanism of miRNAs in the pathogenesis of OSCC may provide novel promising approaches for the identification of prognostic biomarkers and therapeutic targets for this particular malignancy. In the present study, reverse transcription‑quantitative polymerase chain reaction analysis was performed to detect miRNA (miR)‑495 expression in OSCC tissues and cell lines. The effects of miR‑495 on the proliferation and invasion of OSCC cells were determined using Cell Counting Kit‑8 and Matrigel invasion assays, respectively. The mechanisms underlying the action of miR‑495 in OSCC cells were also investigated. Results from the present study revealed that miR‑495 expression was downregulated in OSCC tissues and cell lines compare with in adjacent normal tissues and human oral keratinocytes, respectively. Exogenous expression of miR‑495 restricted cell proliferation and invasion of OSCC cells in vitro. Notch1 was identified as a direct functional target of miR‑495 in OSCC. Furthermore, Notch1 knockdown exhibited inhibitory effects, similar to those induced by miR‑495 overexpression in OSCC cells. Restoration of Notch1 expression rescued the suppressive effects of miR‑495 on OSCC cell proliferation and invasion. These findings suggested an important role for miR‑495 in the regulation of OSCC cell growth and metastasis, at least partly by directly targeting Notch1. In addition, the findings of the present study revealed the potential of miR‑495 as a novel therapeutic target for the treatment of patients with OSCC.

Notch1 serves as a prognostic factor and regulates metastasis via regulating EGFR expression in hypopharyngeal squamous cell carcinoma

Objective

Hypopharyngeal squamous cell carcinoma (HSCC) remains one of the most lethal malignancies in head and neck. Notch1 has been validated to play prominent roles in the occurrence and development of various types of cancer. The aim of this study was to explore the function and underlying mechanism of Notch1 in HSCC.

Patients and methods

Seventy-one cancer tissue samples and adjacent noncancerous formalin-fixed paraffin embedded tissue specimens were analyzed by immunohistochemistry. As Notch1 is overexpressed in HSCC, we further questioned whether there was a relationship between Notch1 and the clinicopathological characteristics. After confirming the successful knockdown of Notch1 by siRNA, the migration and invasion after gene knockdown were investigated by Transwell chambers. We then tried to identify YBX1 and EGFR expression using real-time PCR (RT-PCR) and Western blot analyses. To further determine whether the downexpression of EGFR was caused by YBX1 and the overexpression of YBX1 was caused by gene amplification, the expression of EGFR was detected by RT-PCR and Western blot assays.

Results

We found that the expression of Notch1 and EGFR in HSCC tissues was upregulated compared with those in the adjacent noncancerous tissues. Further clinicopathological characteristics analysis revealed that the expression of Notch1 was positively correlated with distant metastasis (P=0.003) and tumor differentiation (P=0.031). The high expression of Notch1 is an independent prognostic factor for a poor overall survival in patients with HSCC (P=0.015, χ ²=10.403). Knocking down of Notch1 significantly inhibits the migration and invasion of FaDu cells in vitro. Mechanistic investigation reveals that Notch1 knockdown is found suppressing the expression of EGFR at transcriptional level. Interestingly, we further found that Notch1 knockdown also decreased the expression of YBX1, which is a transcription factor of EGFR. Moreover, the upregulation of YBX1 reverses the suppression of Notch1 on EGFR. Furthermore, forced overexpression of YBX1 induced the invasion of FaDu cells.

Conclusion

Taken together, we found a positively cross-linked role of Notch1 signaling in the outcome of HSCC, providing a novel valuable prognostic marker and potential therapeutic target for the treatment of HSCC patients. Notch1 is a core signaling molecule for regulating migration and invasion via interplaying with EGFR in HSCC cells.

Suppression of Notch1 and AKT mediated epithelial to mesenchymal transition by Verrucarin J in metastatic colon cancer

Epithelial to mesenchymal transition (EMT) in colorectal cancer (CRC) has been attributed to activation of AKT and Notch1 signaling pathways. As EMT corresponds to increased aggressiveness of CRC, approaches that prevent metastasis by targeting AKT/Notch1 pathways are at the forefront of current research paradigms. This study examined the anti-metastatic potential of Verrucarin J (VJ), a small molecule, in CRC cells overexpressing AKT and Notch1. VJ significantly inhibited AKT/HCT 116 cell growth by acting on the AKT/NFκB/Bcl-2 signaling axis and initiated apoptotic signaling as was evident from increased expression of pro-apoptotic markers such as cleaved PARP, cleaved caspase 3, and cleaved caspase 9. Also, VJ inhibited the cell growth in AKT/Notch1-overexpressing CRC cells and abrogated EMT. The down-regulation of AKT and Notch1 signaling was apparent in immunoblot analysis and corresponded with down-regulation of mesenchymal markers including Snail, and β-catenin. Intraperitoneal administration of VJ in control (pCMV/HCT 116) and AKT/HCT 116 mice significantly suppressed AKT-induced tumor growth in a xenograft model. In addition, down-regulation of prosurvival markers as well as AKT and Notch1 was observed in the immunohistochemical analysis of the xenografted tumors. In conclusion, our study substantiates the role of AKT and Notch1 in cell proliferation, angiogenesis, and EMT of CRC cells and demonstrates that VJ may be a viable therapeutic option to counter AKT-induced cell proliferation and tumor outgrowth in CRC.