NOTCH1 expression predicts patient prognosis in esophageal squamous cell cancer

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.

A comprehensive multi-omics analysis reveals molecular features associated with cancer via RNA cross-talks in the Notch signaling pathway

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Many Notch genes are identified as cancer-associated genes with an important role in tumorigenesis.

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Dynamic expression patterns are associated with the Notch activity that are largely regulated by multiple ncRNAs.

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Cross-talks among diverse RNAs are crucial in cancers via ceRNA network.

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The Notch pathway shows a robust prognostic ability via integrating multi-omics features as well as their targets.

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The Notch pathway is also correlated with immune infiltration and maybe available cancer treatment drug targets.

The Notch signaling has an important role in multiple cellular processes and is related to carcinogenic process. To understand the potential molecular features of the crucial Notch pathway, a comprehensive multi-omics analysis is performed to explore its contributions in cancer, mainly including analysis of somatic mutation landscape, pan-cancer expression, ncRNA regulation and potential prognostic power. The screened 22 Notch core genes are relative stable in DNA variation. Dynamic expression patterns are associated with the Notch activity, which are mainly regulated by multiple ncRNAs via interactions of ncRNA:mRNA and ceRNA networks. The Notch pathway shows a potential prognostic ability through integrating multi-omics features as well as their targets, and it is correlated with immune infiltration and maybe available drug targets, implying the potential role in individualized treatment. Collectively, all of these findings contribute to exploring crucial role of the key pathway in cancer pathophysiology and gaining mechanistic insights into cross-talks among RNAs and biological pathways, which indicates the possible application of the well-conserved Notch signaling pathway in precision medicine.

The Notch1 gene may control cell chemoresistance in esophageal squamous cell cancer

BACKGROUND

In our previous study, missense mutations in the Notch1 gene were found in chemotherapy-resistant esophageal squamous cell cancer (ESCC) patients. In this study, we explored changes in the interaction between Notch1 and DLL4 resulting from missense mutations.

METHODS

Bioinformatics analysis was performed to assess and compare the different biological structures and functions of wild type (WT) and mutation type (MT) sequences of Notch1. A genetic information search was performed, and the results were analyzed using in silico modeling. Homology modeling of the Notch1 protein was carried out using Swiss-Model software, and modeling of site-directed mutations was carried out using PyMOL software to observe the protein structure. The Notch1-DLL4 ligand-receptor complex protein model was constructed, Wincoot software was used to determine site-directed mutations, and a protein-ligand interaction profiler (PLIP) was used to calculate the noncovalent interactions in the complex.

RESULTS

The mutation site was located in the region where Notch1 binds to DLL4. A careful examination of the in silico structural model revealed that the mutation caused an alteration in the surface charge, and the water-bridge bonds of the interaction between Notch1-DLL4 increased in number from 5 to 7.

CONCLUSIONS

Notch1 gene missense mutation leads to an increase in the number of water-bridge bonds, thus enhancing the Notch1-DLL4 interaction, which may lead to tighter Notch1-DLL4 binding, either making the pathway easier to activate or increasing the length of time it is active.

Molecular analysis of Chinese oesophageal squamous cell carcinoma identifies novel subtypes associated with distinct clinical outcomes

BACKGROUND

Oesophageal squamous cell carcinoma (ESCC) is a highly heterogeneous cancer with a distinct incidence and prognosis. Molecular events driving ESCC subtypes and prognosis have not been established, and little is known regarding Chinese ESCC patients in Xinjiang, China.

METHODS

Here, we first integrated the genomic and transcriptomic data of 125 Chinese ESCC patients from Xinjiang Tumor Hospital (Urumqi, China). Two independent datasets of GSE53624 and The Cancer Genome Atlas (TCGA) ESCC were used to confirm the results of this study. DNA mutation and overall survival (OS) were analysed independently in the Chinese ESCC cohorts.

FINDINGS

Genomic analyses revealed a consistent mutation signatures and discordance among mutated genes across the different ESCC cohorts. In addition, transcriptomic profiling identified three Chinese ESCC subtypes associated with clinical and molecular attributes, including patient survival, lymph node status and genetic profile. Moreover, Chinese ESCC subtypes have distinct metabolic, inflammatory, metastatic, and cell proliferation features and unique potential therapeutics. Furthermore, the expression of cell cycle- and/or cell proliferation-related genes was higher in cyclin D1 (CCND1)-amplified tumours than in CCND1-normal tumours from Chinese ESCC patients, suggesting that CCND1 amplification promoted cell proliferation.

INTERPRETATION

Our findings provide a framework to facilitate the rational categorization of ESCC in Chinese patients and a foundation for new therapies.

FUNDING

This study was supported by the Research Fund of Key Laboratory of Xinjiang oncology (Grant no.2017D04006) and the Outstanding Youth Science and technology training project fund of Xinjiang, China (Grant no. 2017Q058).

Interleukin-23 receptor signaling mediates cancer dormancy and radioresistance in human esophageal squamous carcinoma cells via the Wnt/Notch pathway

Abstract

In the tumor microenvironment, inflammatory cells and molecules influence almost every process; among them, interleukin-23 (IL-23) is a pro-inflammatory molecule that exhibits pro- or anti-tumor properties, but both activities remain poorly understood. In this study, we investigated the effect of extracellular IL-23 in IL-23 receptor-positive (IL-23R⁺) esophageal squamous cell carcinoma (ESCC) and explored the mechanisms underlying this effect. We analyzed ESCC tumor tissues by immunohistochemical and immunofluorescence staining and found that IL-23, which was highly expressed, co-localized with Oct-4A in IL-23R⁺ ESCC cells. In addition, IL-23 treatment significantly increased the accumulation of CD133⁺ cells and activated the Wnt and Notch signaling pathways in CD133⁻IL-23R⁺ ESCC cell lines. Consistently, CD133⁻IL-23R⁺ cells pretreated with IL-23 showed stronger anti-apoptosis activity when exposed to radiation and higher survival than untreated groups. Moreover, the inhibition of Wnt/Notch signaling by a small-molecule inhibitor or siRNA abolished the effect of IL-23-induced dormancy and consequent radioresistance. Taken together, these results suggested that IL-23 facilitates radioresistance in ESCC by activating Wnt/Notch-mediated G0/1 phase arrest, and attenuating these detrimental changes by blocking the formation of dormancy may prove to be an effective pretreatment for radiotherapy.

Key messages

IL-23/IL-23R is correlated with the acquisition of stem-like potential in ESCC.

CD133⁻IL-23R⁺ ESCCs acquired dormancy via IL-23.

Radioresistance depends on IL-23-mediated Wnt/Notch pathway activation in vitro and vivo.

Electronic supplementary material

The online version of this article (10.1007/s00109-018-1724-8) contains supplementary material, which is available to authorized users.

A systematic analysis of the association between Notch1 expression and the patients with digestive tract cancers

AIM

Notch1 expression remains controversial on digestive tract cancers. This meta-analysis was performed to assess the clinicopathological significance of Notch1 expression in individuals with digestive tract cancers, mainly involving esophageal squamous cell carcinoma (ESCC), gastric cancer (GC), pancreatic cancer (PC) and colorectal cancer (CRC).

METHODS

Available articles were searched from the online databases, and the meta-analysis was done using Review Manager software 5.3.

RESULTS

35 studies were included in this analysis (6187 samples). Notch1 is downregulated in esophageal squamous cell carcinoma (p < 0.00001), Notch1 expression at high levels was detected in GC (p = 0.02) and CRC (p < 0.001), and no significant difference exists between PC and normal tissue (p = 0.76).

CONCLUSION

Notch1 overexpression in GC and CRC suggested aggressive biological behaviors, and Notch1 may be a biomarker in digestive tract cancers.

Novel transduction of nutrient stress to Notch pathway by RasGRP3 promotes malignant aggressiveness in human esophageal squamous cell carcinoma

In the process of enlarging of tumors, the dissolving tissue structures and remodeling endothelial cells for restoring gas exchange and nutritional support, further facilitate tumor cell invasion and metastasis. Activation of Ras plays a critical role in the development of esophageal squamous cell carcinoma (ESCC), but the underlying mechanisms remain poorly understood. We therefore investigated whether Ras guanyl-releasing protein 3 (RasGRP3), a Ras activator, could promote metastasis by inducing vascular regeneration and further epithelial-mesenchymal transition under nutrient stress (NS). In the present study, we explored that the accumulation of RasGRP3 regulated vascular endothelial growth factor-A production, co-stimulated Notch pathway with high expression of Notch intracellular domain (NICD) and Hes1. Moreover, ESCC cells under NS increased the expression of vimentin, Snail, Slug and MMP9 proteins; while inhibition of Notch activation by DAPT (a γ-secretase inhibitor) or RasGRP3-targeted RNA interference prevented from the effect. In conclusion, these findings provide a new insight into the upregulation of RasGRP3 involved in Notch pathway activation in the development of ESCC, especially under nutrient deprivation.

NOTCH receptors in gastric and other gastrointestinal cancers: oncogenes or tumor suppressors?

Gastric cancer (GC) ranks the most common cancer types and is one of the leading causes of cancer-related death. Due to delayed diagnosis and high metastatic frequency, 5-year survival rate of GC is rather low. It is a complex disease resulting from the interaction between environmental factors and host genetic alterations that deregulate multiple signaling pathways. The Notch signaling pathway, a highly conserved system in the regulation of the fate in several cell types, plays a pivotal role in cell differentiation, survival and proliferation. Notch is also one of the most commonly activated signaling pathways in tumors and its aberrant activation plays a key role in cancer advancement. Whether Notch cascade exerts oncogenic or tumor suppressive function in different cancer types depends on the cellular context. Mammals have four NOTCH receptors that modulate Notch pathway activity. In this review, we provide a comprehensive summary on the functional role of NOTCH receptors in gastric and other gastrointestinal cancers. Increasing knowledge of NOTCH receptors in gastrointestinal cancers will help us recognize the underlying mechanisms of Notch signaling and develop novel therapeutic strategies for GC.

Notch2 as a promising prognostic biomarker for oesophageal squamous cell carcinoma

We aimed to examine Notch2 expression in oesophageal squamous cell carcinoma (ESCC) patients and to evaluate its prognostic potential. Immunohistochemical (IHC) staining, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis were utilized to investigate the Notch2 expression status and prognostic value. Furtherly, CCK8 and clonogenic assays were conducted to determine if Notch2 inhibition by shRNA could lead to a decrease in the proliferation and survival of ESCC cells. A notably higher Notch2 expression level was found in ESCC tissues at the mRNA (P < 0.0001) and protein levels (IHC: P = 0.004; western blot: P = 0.021). Log-rank analysis demonstrated that Notch2 overexpression was significantly associated with worse overall survival (OS) (29.1% vs. 49.1%; P = 0.013) and progression-free survival (PFS) (15.3% vs. 34.4%; P = 0.006) rates in ESCC patients. The multivariate analysis revealed Notch2 as an independent prognostic factor for OS and PFS (P = 0.002 and 0.006, resp.). Besides, in vitro assays showed that OD450 values and colony formations were significantly reduced in Notch2-shRNA group (all P < 0.0001). In conclusion, these results show that Notch2 is up-regulated in ESCC tissues and could serve as a promising biomarker for identifying individuals with poor prognostic potential.

Genomic Characterization of Esophageal Squamous Cell Carcinoma Reveals Critical Genes Underlying Tumorigenesis and Poor Prognosis

The genetic mechanisms underlying the poor prognosis of esophageal squamous cell carcinoma (ESCC) are not well understood. Here, we report somatic mutations found in ESCC from sequencing 10 whole-genome and 57 whole-exome matched tumor-normal sample pairs. Among the identified genes, we characterized mutations in VANGL1 and showed that they accelerated cell growth in vitro. We also found that five other genes, including three coding genes (SHANK2, MYBL2, FADD) and two non-coding genes (miR-4707-5p, PCAT1), were involved in somatic copy-number alterations (SCNAs) or structural variants (SVs). A survival analysis based on the expression profiles of 321 individuals with ESCC indicated that these genes were significantly associated with poorer survival. Subsequently, we performed functional studies, which showed that miR-4707-5p and MYBL2 promoted proliferation and metastasis. Together, our results shed light on somatic mutations and genomic events that contribute to ESCC tumorigenesis and prognosis and might suggest therapeutic targets.

Genomic analyses reveal FAM84B and the NOTCH pathway are associated with the progression of esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is the sixth most lethal cancer worldwide and the fourth most lethal cancer in China. Genomic characterization of tumors, particularly those of different stages, is likely to reveal additional oncogenic mechanisms. Although copy number alterations and somatic point mutations associated with the development of ESCC have been identified by array-based technologies and genome-wide studies, the genomic characterization of ESCCs from different stages of the disease has not been explored. Here, we have performed either whole-genome sequencing or whole-exome sequencing on 51 stage I and 53 stage III ESCC patients to characterize the genomic alterations that occur during the various clinical stages of ESCC, and further validated these changes in 36 atypical hyperplasia samples.

RESULTS

Recurrent somatic amplifications at 8q were found to be enriched in stage I tumors and the deletions of 4p-q and 5q were particularly identified in stage III tumors. In particular, the FAM84B gene was amplified and overexpressed in preclinical and ESCC tumors. Knockdown of FAM84B in ESCC cell lines significantly reduced in vitro cell growth, migration and invasion. Although the cancer-associated genes TP53, PIK3CA, CDKN2A and their pathways showed no significant difference between stage I and stage III tumors, we identified and validated a prevalence of mutations in NOTCH1 and in the NOTCH pathway that indicate that they are involved in the preclinical and early stages of ESCC.

CONCLUSIONS

Our results suggest that FAM84B and the NOTCH pathway are involved in the progression of ESCC and may be potential diagnostic targets for ESCC susceptibility.

Clinicopathological significance of Notch1 expression in cervical cancer patients: a meta-analysis

Aim: Notch1 expression remains incompatible and contradictory with previous findings on cervical cancer. The purpose of this study is to evaluate the association between Notch1 and cervical cancer. Methods: Available studies were searched from diverse databases and Review Managers 5.3 software was used to perform analysis. Results: A total of 798 samples were included in this meta-analysis. The Notch1 expression in cancer tissues was higher than that in precancer (p = 0.0003) and normal tissues (p < 0.02). However, the difference of Notch1 expression between cancer cases and precancer cases has no statistical significance (p = 0.35). Moreover, lymph node metastasis (p = 0.02) was associated with higher Notch1 expression in cervical cancer. Conclusion: Notch1 over-expression indicated aggressive biological behaviors.

Notch and Wnt signaling pathway in cancer: Crucial role and potential therapeutic targets (Review)

There is no radical cure for all cancer types. The most frequently used therapies are surgical treatment, radiotherapy and chemotherapy. However, recrudescence, radiation resistance and chemotherapy resistance are the most challenging issues in clinical practice. To address these issues, they should be further studied at the molecular level, and the signaling pathways involved represent a promising avenue for this research. In the present review, we mainly discuss the components and mechanisms of activation of the Notch and Wnt signaling pathways, and we summarize the recent research efforts on these two pathways in different cancers. We also evaluate the ideal drugs that could target these two signaling pathways for cancer therapy, summarize alterations in the Notch and Wnt signaling pathways in cancer, and discuss potential signaling inhibitors as effective drugs for cancer therapy.

Hepatitis B virus X protein activates Notch signaling by its effects on Notch1 and Notch4 in human hepatocellular carcinoma

Deregulated expression of Notch receptors and abnormal activity of Notch signaling have been observed in a growing number of malignant tumors, however, the expression and activity of Notch in hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC) and their relationship with HBV X protein (HBx) are still not fully elucidated. To address this, we examined the overall expression of Notch receptors in HBV-associated HCC tissues, analyzed their relationship with HBx, and further investigated the role of Notch signaling in HBx stable transfected HepG2 cells (HepG2X). The results showed that Notch signaling could be activated by HBx in HepG2 cells. The expression of cytoplasmic Notch1 or nuclear Notch4 was correlated with the expression of HBx in HBV-associated HCC tissues. The expression of cytoplasmic Notch1 or nuclear Notch4 could also be upregulated by HBx in HepG2X cells. The upregulation of Notch1 by HBx was through p38 MAPK pathway. Moreover, HBx was found to directly interact with Notch1, whereas, not with Notch4 in HepG2X cells. Suppression of Notch signaling by γ-secretase inhibitor (GSI) decreased cell growth, blocked cell cycle progression and induced cell apoptosis in HepG2X cells. The present study indicates that HBx activates Notch signaling by its effects on Notch1 and Notch4, and therefore, recruits Notch signaling as a downstream pathway contributing to its carcinogenic role in HBV-associated HCC.

Prognostic value of Notch-1 expression in hepatocellular carcinoma: a meta-analysis

Association of Notch-1 expression with prognosis of patients with hepatocellular carcinoma (HCC) remains controversial. We conducted a meta-analysis to reevaluate the association of Notch-1 expression with clinicopathological characteristics and prognosis of HCC. PubMed, Embase, Web of Science, and China National Knowledge Infrastructure were searched to look for relevant studies. The association between Notch-1 expression and clinicopathological parameters and overall survival (OS) was then reassessed using the meta-analysis for odds ratio (OR) or hazard ratio (HR) and 95% confidence interval (CI). A total of seven studies, including 810 HCC patients, were eligible for the meta-analysis. Our data showed that high Notch-1 expression was able to predict poor OS (HR 1.50, 95% CI 1.17–1.83, P=0.0001). The pooled OR showed that high Notch-1 expression was significantly associated with tumor metastasis (OR 0.37, 95% CI 0.16–0.86, P=0.02) and tumor size >5 cm (OR 0.48, 95% CI 0.26–0.88, P=0.02). In contrast, there was no association between high Notch-1 expression and tumor differentiation, late TNM stage, tumor number, and portal vein invasion of HCC. In conclusion, Notch-1 overexpression might predict poorer survival and more aggressive behavior in patients with HCC.

Thymoquinone Pretreatment Overcomes the Insensitivity and Potentiates the Antitumor Effect of Gemcitabine Through Abrogation of Notch1, PI3K/Akt/mTOR Regulated Signaling Pathways in Pancreatic Cancer

BACKGROUND

The gemcitabine-insensitivity remains the main challenge for pancreatic cancer treatment. Thymoquinone, the predominant bioactive ingredient of Nigella sativa, has been shown to possess promising anti-cancer and chemo-sensitizing effects on pancreatic cancer, however, its meticulous mechanism is still indistinct.

AIM

The objective of the present study was to investigate the potency of thymoquinone in combination with gemcitabine in inducing apoptosis and preventing the development of gemcitabine-insensitivity in pancreatic cancer cells.

METHODS

The anti-tumor effects of thymoquinone and gemcitabine were analyzed via evaluation of alterations of cell viability, tumor weight, apoptosis-related proteins, caspase-3, -9 activities and NF-κB DNA binding activity in pancreatic cancer cells in vitro and PANC-1 cells orthotopic xenograft in vivo.

RESULTS

Thymoquinone pretreatment following gemcitabine treatment synergistically caused an increase in pancreatic cancer cells apoptosis and tumor growth inhibition both in vitro and in vivo. The novel combinational regimen also contributes to alterations of multiple molecular signaling targets, such as the suppression of Notch1, NICD accompanying with up-regulation of PTEN, the inactivation of Akt/mTOR/S6 signaling pathways, and the suppression of phosphorylation and nuclear translocation of p65 induced by TNF-α. Thymoquinone pretreatment and gemcitabine also induced down-regulation of anti-apoptotic Bcl-2, Bcl-xL, XIAP and up-regulation and activation of pro-apoptotic molecules including Caspase-3, Caspase-9, Bax and increased release of cytochrome c.

CONCLUSIONS

This novel modality of thymoquinone pretreatment can enhance the anti-cancer activity of gemcitabine and may be a promising option in the treatment of pancreatic cancer.