Nectin-3 is a new biomarker that mediates the upregulation of MMP2 and MMP9 in ovarian cancer cells

Identification of Poliovirus Receptor-like 3 Protein as a Prognostic Factor in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) represents an aggressive subtype of breast cancer, with a bad prognosis and lack of targeted therapeutic options. Characterized by the absence of estrogen receptors, progesterone receptors, and HER2 expression, TNBC is often associated with a significantly lower survival rate compared to other breast cancer subtypes. Our study aimed to explore the prognostic significance of 83 immune-related genes, by using transcriptomic data from the TCGA database. Our analysis identified the Poliovirus Receptor-Like 3 protein (PVRL3) as a critical negative prognostic marker in TNBC patients. Furthermore, we found that the Enhancer of Zeste Homolog 2 (EZH2), a well-known epigenetic regulator, plays a pivotal role in modulating PVRL3 levels in TNBC cancer cell lines expressing EZH2 along with high levels of PVRL3. The elucidation of the EZH2-PVRL3 regulatory axis provides valuable insights into the molecular mechanisms underlying TNBC aggressiveness and opens up potential pathways for personalized therapeutic intervention.

Identification of the biological functions and chemo-therapeutic responses of ITGB superfamily in ovarian cancer

BACKGROUND

Patients with ovarian cancer (OC) tend to face a poor prognosis due to a lack of typical symptoms and a high rate of recurrence and chemo-resistance. Therefore, identifying representative and reliable biomarkers for early diagnosis and prediction of chemo-therapeutic responses is vital for improving the prognosis of OC.

METHODS

Expression levels, IHC staining, and subcellular distribution of eight ITGBs were analyzed using The Cancer Genome Atlas (TCGA)-Ovarian Serous Cystadenocarcinoma (OV) database, GEO DataSets, and the HPA website. PrognoScan and Univariate Cox were used for prognostic analysis. TIDE database, TIMER database, and GSCA database were used to analyze the correlation between immune functions and ITGBs. Consensus clustering analysis was performed to subtype OC patients in the TCGA database. LASSO regression was used to construct the predictive model. The Cytoscape software was used for identifying hub genes. The 'pRRophetic' R package was applied to predict chemo-therapeutic responses of ITGBs.

RESULTS

ITGBs were upregulated in OC tissues except ITGB1 and ITGB3. High expression of ITGBs correlated with an unfavorable prognosis of OC except ITGB2. In OC, there was a strong correlation between immune responses and ITGB2, 6, and 7. In addition, the expression matrix of eight ITGBs divided the TCGA-OV database into two subgroups. Subgroup A showed upregulation of eight ITGBs. The predictive model distinguishes OC patients from favorable prognosis to poor prognosis. Chemo-therapeutic responses showed that ITGBs were able to predict responses of common chemo-therapeutic drugs for patients with OC.

CONCLUSIONS

This article provides evidence for predicting prognosis, immuno-, and chemo-therapeutic responses of ITGBs in OC and reveals related biological functions of ITGBs in OC.

CD155 as an emerging target in tumor immunotherapy

CD155 is an immunoglobulin-like protein overexpressed in almost all the tumor cells, which not only promotes proliferation, adhesion, invasion, and migration of tumor cells, but also regulates immune responses by interacting with TIGIT, CD226 or CD96 receptors expressed on several immune cells, thereby modulating the functionality of these cellular subsets. As a novel immune checkpoint, the inhibition of CD155/TIGIT, either as a standalone treatment or in conjunction with other immune checkpoint inhibitors, has demonstrated efficacy in managing advanced solid malignancies. In this review, we summarize the intricate relationship between on tumor surface CD155 and its receptors, with further discussion on how they regulate the occurrence of tumor immune escape. In addition, novel therapeutic strategies and clinical trials targeting CD155 and its receptors are summarized, providing a strong rationale and way forward for the development of next-generation immunotherapies.

Comprehensive Analysis of MICALL2 Reveals Its Potential Roles in EGFR Stabilization and Ovarian Cancer Cell Invasion

Molecules interacting with CasL (MICALs) are critical mediators of cell motility that act by cytoskeleton rearrangement. However, the molecular mechanisms underlying the regulation of cancer cell invasion remain elusive. The aim of this study was to investigate the potential role of one member of MICALs, i.e., MICALL2, in the invasion and function of ovarian cancer cells. We showed by bioinformatics analysis that MICALL2 expression was significantly higher in tissues of advanced-stage ovarian cancer and associated with poor overall survival of patients. MICALL2 was strongly correlated with the infiltration of multiple types of immune cells and T-cell exhaustion markers. Moreover, enrichment analyses showed that MICALL2 was involved in the tumor-related matrix degradation pathway. Mechanistically, MMP9 was identified as the target gene of MICALL2 for the regulation of invadopodium formation and SKOV3, HO-8910PM cell invasion. In addition, EGFR-AKT-mTOR signaling was identified as the downstream pathway of MICALL2 in the regulation of MMP9 expression. Furthermore, MICALL2 silencing promoted EGFR degradation; however, this effect was abrogated by treatment with the autophagy inhibitors acadesine and chloroquine diphosphate. Silencing of MICALL2 resulted in a suppressive activity of Rac1 while suppressing Rac1 activation attenuated the pro-EGFR, pro-MMP9, and proinvasive effects induced by the overexpression of MICALL2. Collectively, our results indicated that MICALL2 participated in the process of immune infiltration and invasion by ovarian cancer cells. Moreover, MICALL2 prevented EGFR degradation in a Rac1-dependent manner, consequently leading to EGFR-AKT-mTOR-MMP9 signaling activation and invadopodia-mediated matrix degradation.

miR-1180 Targets FXYD5 to Regulate Pancreatic Cancer Cells Migration and Invasion

Pancreatic cancer is a fatal malignancy typically diagnosed in older males and has an aggressive progression. The function of the miR-1180/FXYD5 axis in pancreatic cancer malignant behaviors was investigated. 20 pairs of pancreatic cancer and adjacent normal tissue samples were harvested from pancreatic cancer patients, and qRT-PCR, IHC, and western blot assays were performed, respectively, to detect the mRNA expression and protein levels of miR-1180 or FXYD5. Transwell and scratch assays were conducted to detect the migratory and invasive ability of pancreatic cancer cells; a Dual-luciferase reporter assay was employed to validate miR-1180 targeting FXYD5. miR-1180 targeting FXYD5 to regulate the migratory and invasive ability of pancreatic cancer cells was validated in mouse xenograft tumor models. FXYD5 expression was increased in pancreatic cancer tissue samples than in adjacent normal tissue samples (P < 0.01), and FXYD5 expression exhibited a positive correlation with the migratory and invasive ability of pancreatic cancer cells. miR-1180 targeted FXYD5 and negatively regulated FXYD5. Restoring miR-1180 expression could inhibit the migratory and invasive ability of pancreatic cancer cells (P < 0.01), and this effect could potentially be alleviated by FXYD5 overexpression. The miR-1180/FXYD5 axis positively regulated E-cadherin and negatively regulated MMP2 and MMP9 expression levels. In vivo findings demonstrated that miR-1180 overexpression inhibited tumor growth and lung metastasis (P < 0.05), while FXYD5 overexpression promoted tumor growth and lung metastasis (P < 0.05). In conclusion, the miR-1180 /FXYD5 axis could be involved in pancreatic cancer metastasis through the regulation of EMT and extracellular matrix degradation.

RARγ promotes the invasion and metastasis of thyroid carcinoma by activating the JAK1-STAT3-CD24/MMPs axis

The nuclear receptor superfamily RAR is generally considered to play a crucial role in the development of tumors by regulating the transcription of target genes. Nevertheless, whether RARγ performs tumor-promoting or tumor-suppressing functions and its specific mechanism in thyroid carcinoma (TC) remain unknown. Here, our study demonstrated that RARγ was abnormally overexpressed in TC tissues compared with normal thyroid tissues. Moreover, RARγ expression was remarkably correlated with cell phenotypes such as cell proliferation, migration and invasion. Mechanistically, RARγ knockdown effectively decreased the phosphorylation levels of JAK1 and STAT3, leading to decreased expression of the membrane protein CD24. In a coculture system, TC cells with high levels of CD24 in the membrane were more likely to escape phagocytosis by macrophages via the combination of CD24 with the inhibitory receptor Siglec-10 in the membrane of macrophages. In contrast, the ability of macrophages to engulf TC cells was notably elevated through exogenous addition of CD24 antibody. Collectively, our study revealed a previously undiscovered molecular mechanism of RARγ in promoting the development of TC, shedding light on RARγ as a promising therapeutic target for TC.

Clinical Significance of Nectins in HCC and Other Solid Malignant Tumors: Implications for Prognosis and New Treatment Opportunities-A Systematic Review

The nectin family comprises four proteins, nectin-1 to -4, which act as cell adhesion molecules. Nectins have various regulatory functions in the immune system and can be upregulated or decreased in different tumors. The literature research was conducted manually by the authors using the PubMed database by searching articles published before 2023 with the combination of several nectin-related keywords. A total of 43 studies were included in the main section of the review. Nectins-1-3 have different expressions in tumors. Both the loss of expression and overexpression could be negative prognostic factors. Nectin-4 is the best characterized and the most consistently overexpressed in various tumors, which generally correlates with a worse prognosis. New treatments based on targeting nectin-4 are currently being developed. Enfortumab vedotin is a potent antibody-drug conjugate approved for use in therapy against urothelial carcinoma. Few reports focus on hepatocellular carcinoma, which leaves room for further studies comparing the utility of nectins with commonly used markers.

UBP43 promotes epithelial ovarian carcinogenesis via activation of β-catenin signaling pathway

Dysregulation of the deubiquitinating protease, UBP43, has been implicated in many human diseases, including cancer. Here, we evaluated the functional significance and mechanism of action of UBP43 in epithelial ovarian cancer. We found that UBP43 was significantly upregulated in the tumor tissues of patients with epithelial ovarian cancer. Similar results were observed in OVCAR-3, Caov-3, TOV-112D, A2780, and SK-OV-3 cells. Furthermore, in vitro functional assays of A2780 and TOV-112D cells demonstrated that UBP43 overexpression promoted cell proliferation, migration, and invasion. Upregulation of UBP43 might result in epithelial-mesenchymal transition by inducing the nuclear transport of β-catenin, which was accompanied by enhanced N-cadherin but decreased E-cadherin expression. These malignant phenotypes were reversed by UBP43 silencing. Further investigation revealed that the knockdown of UBP43 inhibited cell proliferation by inducing a cell cycle arrest at the G2/M phase. The oncogenic characteristics of UBP43 were validated in a subcutaneous xenograft mouse model. In vivo, tumor growth was delayed in the UBP43-silenced group but accelerated after UBP43 overexpression. Finally, we demonstrated that β-catenin is a key protein in the UBP43-mediated malignant development of epithelial ovarian cancer. Specifically, overexpression of UBP43 decreased the ubiquitination degradation of β-catenin and enhanced its protein stability. Also, we observed that the downstream genes of beta-catenin such as cyclin D1, MMP2, and MMP9 were upregulated due to UBP43 overexpression. Thus, we concluded that UBP43 promoted epithelial ovarian cancer tumorigenesis and metastasis through activation of the β-catenin pathway, suggesting that UBP43 may be a potential therapeutic target for this intractable disease.

The Prognostic Significance of Nectin-2 and Nectin-4 expression in glial tumors

Glial tumors are the most frequent neoplasms of the central nervous system in adults and despite recent advances in diagnosis and treatment of the disease, the prognosis of glioma is poor. Therefore, there is a great need to identify new prognostic factors and potential immunotherapeutic targets. Members of the Nectin family of proteins are gaining significant attention as possible diagnostic and immunotherapeutic targets in many solid tumors, but they have not been extensively investigated in glial tumors. The aim of the present study was to evaluate the expression of Nectin-2 and Nectin-4 in glial tumors of different grades, and to assess their prognostic value. The results showed heterogeneous expression of Nectin-2 and Nectin-4 in tumor cells and neuropil, with significantly higher Nectin-2 expression compared to Nectin-4, but without differences among tumor grades. In addition, the expression of Nectin-2 and Nectin-4 was associated with shorter survival times in patients with grade II/III gliomas. These results suggest that Nectin-2 and Nectin-4 expression may be used as an independent prognostic indicator for patients with II/III gliomas. This study contributes to the development of personalized care for patients with glioma and provides a basis for further research on nectin-based immunotherapy for brain tumors.

Nectins and Nectin-like Molecules in Colorectal Cancer: Role in Diagnostics, Prognostic Values, and Emerging Treatment Options: A Literature Review

In 2020, colorectal cancer was the third most common type of cancer worldwide with a clearly visible increase in the number of cases each year. With relatively high mortality rates and an uncertain prognosis, colorectal cancer is a serious health problem. There is an urgent need to investigate its specific mechanism of carcinogenesis and progression in order to develop new strategies of action against this cancer. Nectins and Nectin-like molecules are cell adhesion molecules that take part in a plethora of essential processes in healthy tissues as well as mediating substantial actions for tumor initiation and evolution. Our understanding of their role and a viable application of this in anti-cancer therapy has rapidly improved in recent years. This review summarizes the current data on the role nectins and Nectin-like molecules play in colorectal cancer.

The Dual Blockade of the TIGIT and PD-1/PD-L1 Pathway as a New Hope for Ovarian Cancer Patients

The prognosis for ovarian cancer (OC) patients is poor and the five-year survival rate is only 47%. Immune checkpoints (ICPs) appear to be the potential targets in up-and-coming OC treatment. However, the response of OC patients to immunotherapy based on programmed cell death pathway (PD-1/PD-L1) inhibitors totals only 6-15%. The promising approach is a combined therapy, including other ICPs such as the T-cell immunoglobulin and ITIM domain/CD155/DNAX accessory molecule-1 (TIGIT/CD155/DNAM-1) axis. Preclinical studies in a murine model of colorectal cancer showed that the dual blockade of PD-1/PD-L1 and TIGIT led to remission in the whole studied group vs. the regression of the tumors with the blockade of a single pathway. The approach stimulates the effector activity of T cells and NK cells, and redirects the immune system activity against the tumor. The understanding of the synergistic action of the TIGIT and PD-1/PD-L1 blockade is, however, poor. Thus, the aim of this review is to summarize the current knowledge about the mode of action of the dual TIGIT and PD-1/PD-L1 blockade and its potential benefits for OC patients. Considering the positive impact of this combined therapy in malignancies, including lung and colorectal cancer, it appears to be a promising approach in OC treatment.

The Anti-Nectin 4: A Promising Tumor Cells Target. A Systematic Review

The nectin cell adhesion protein 4 (Nectin-4) is overexpressed in multiple human malignancies. Such aberrant expression is correlated with cancer progression and poor prognostic. Nectin-4 has emerged as a potential biomarker and promising targeted therapy. This review aimed to gather the current state of the literature about Nectin-4 relevance in preclinical tumor models and to summarize its clinical relevance regarding cancer. A systematic assessment of literature articles was performed by searching in PUBMED (MEDLINE) from the database inception to May 2021, following PRISMA guidelines. Preclinical models unanimously demonstrated membrane and cytoplasmic location of the Nectin-4. Furthermore, Nectin-4 was overexpressed whatever the location of the solid tumors. Interestingly, a heterogeneity of Nectin-4 expression has been highlighted in bladder urothelial carcinoma. High serum Nectin-4 level was correlated with treatment efficiency and disease progression. Finally, generated Anti-drug-Conjugated targeting Nectin-4 induced cell death in multiple tumor cell lines. Nectin-4 emerge as a promising target for anti-cancer drugs development because of its central role in tumorigenesis, and lymphangiogenesis. Enfortumab vedotin targeting Nectin-4 demonstrated encouraging results and should be extended to other types of solid tumors.

Transcriptional and Epigenetic Bioinformatic Analysis of Claudin-9 Regulation in Gastric Cancer

Gastric cancer is a heterogeneous disease that represents 5% to 10% of all new cancer cases worldwide. Advances in histological diagnosis and the discovery of new genes have admitted new genomic classifications. Nevertheless, the bioinformatic analysis of gastric cancer databases has favored the detection of specific differentially expressed genes with biological significance. Claudins, a family of proteins involved in tight junction physiology, have emerged as the key regulators of cellular processes, such as growth, proliferation, and migration, associated with cancer progression. The expression of Claudin-9 in the gastric cancer tissue has been linked to poor prognosis, however, its transcriptional and epigenetic regulations demand a more comprehensive analysis. Using the neural network promoter prediction, TransFact, Uniprot-KB, Expasy-SOPMA, protein data bank, proteomics DB, Interpro, BioGRID, String, and the FASTA protein sequence databases and software, we found the following: (1) the promoter sequence has an unconventional structure, including different transcriptional regulation elements distributed throughout it, (2) GATA 4, GATA 6, and KLF5 are the key regulators of Claudin-9 expression, (3) Oct1, NF-κB, AP-1, c-Ets-1, and HNF-3β have the higher binding affinity to the CLDN9 promoter, (4) Claudin-9 interacts with cell differentiation and development proteins, (5) CLDN9 is highly methylated, and (6) Claudin-9 expression is associated with poor survival. In conclusion, Claudin-9 is a protein that should be considered a diagnostic marker as its gene promoter region binds to the transcription factors associated with the deregulation of cell control, enhanced cell proliferation, and metastasis.

Orosomucoid 1 promotes epirubicin resistance in breast cancer by upregulating the expression of matrix metalloproteinases 2 and 9

Orosomucoid 1 (ORM1) has been shown to be upregulated in the serum of breast cancer patients; however, the expression and function of ORM1 in breast cancer remains unknown. We measured the expression of ORM1 in breast cancer tissues and cell lines using qRT-PCR. A colony formation assay was done to assess cell proliferation and Transwell and wound healing assays were performed to determine the migration and invasion capacity of the cells, respectively. In addition, a CCK-8 assay was used to measure epirubicin cytotoxicity and western blot assays were done to analyze the putative mechanisms of epirubicin sensitivity. We found that the expression of ORM1 was upregulated in breast cancer tissues and cell lines. The expression of ORM1 enhanced the proliferation and migration of the cell lines. In contrast, down-regulation of ORM1 inhibited the expression of MMP-2 and MMP-9 and activation of the AKT/ERK signaling pathway. Therefore, ORM1 may represent a potential therapeutic target for breast cancer and promote epirubicin resistance by regulating the expression of MMP-2 and MMP-9, as well as activating the AKT/ERK signaling pathway.

Emerging roles of the nectin family of cell adhesion molecules in tumour-associated pathways

Tumour cells achieve maximum survival by modifying cellular machineries associated with processes such as cell division, migration, survival, and apoptosis, resulting in genetically complex and heterogeneous populations. While nectin and nectin-like cell adhesion molecules control development and maintenance of multicellular organisation in higher vertebrates by mediating cell-cell adhesion and related signalling processes, recent studies indicate that they also critically regulate growth and development of different types of cancers. In this review, we detail current knowledge about the role of nectin family members in various tumours. Furthermore, we also analyse the seemingly opposing roles of some members of nectin family in tumour-associated pathways, as they function as both tumour suppressors and oncogenes. Understanding this functional duality of nectin family in tumours will further our knowledge of molecular mechanisms regulating tumour development and progression, and contribute to the advancement of tumour diagnosis and therapy.

Ethanol Extracts of Solanum lyratum Thunb Regulate Ovarian Cancer Cell Proliferation, Apoptosis, and Epithelial-to-Mesenchymal Transition (EMT) via the ROS-Mediated p53 Pathway

Ovarian cancer is a type of common gynecological tumors with high incidence and poor survival. The anticancer effects of the traditional Chinese medicine Solanum lyratum Thunb (SLT) have been intensively investigated in various cancers but in ovarian cancer is rare. The current study is aimed at investigating the effect of SLT on ovarian cancer cells. Lactate dehydrogenase (LDH) and MTT assays indicated that SLT concentrations of 0.25 and 0.5 μg/mL were not cytotoxic and had significant inhibitory effects on the cell viabilities of A2780 and SKOV3 cells, hence were used for subsequent experiments. Flow cytometric and western blot analysis revealed that SLT effectively suppressed ovarian cancer cell proliferation via inducing cell cycle arrest and increasing apoptosis. Cell cycle and apoptosis-related protein expressions were also regulated in SLT-treated cells. Moreover, DCFH-DA and western blot assays demonstrated that SLT enhanced ROS accumulation and subsequently activated the p53 signaling pathway. However, SLT-regulated ovarian cancer cell proliferation, apoptosis, migration, invasion, and EMT were significantly reversed by an ROS inhibitor (NAC, N-acetyl-L-cysteine). Furthermore, A2780 and SKOV3 cells cocultured with M0 macrophages showed that SLT activated the polarization of M0 macrophages to M1 macrophages and inhibited the polarization to M2 macrophages, with the increased percentage of CD86+ cells and decreased percentage of CD206+ cells were detected. In summary, this study illustrated the anticancer effects of SLT on ovarian cancer cells, suggesting that SLT may have the potential to provide basic evidence for the discovery of antiovarian cancer agents.

SLC39A1 contribute to malignant progression and have clinical prognostic impact in gliomas

BACKGROUND

Gliomas are one of the most common primary tumors of the central nervous system, and have an unfavorable prognosis. SLC39A1 is a zinc ion transport protein which inhibits the progression of prostate cancer. By studying the role and mechanism of SLC39A1 in the progression of gliomas, perhaps a new therapeutic target can be provided for their treatment.

METHOD

The TCGA, CCGA, GSE16011, GSE44971 and GSE11260 data sets were employed to evaluate the expression level of SLC39A1 in paracancerous and glioma tissues. In addition, Kaplan-Meier analysis, Cox analysis, and the ESTIMATE and CIBERSORT algorithms were used to analyze its prognostic value and immune infiltration correlation. A CCK-8 and flow cytometer were used to measure the effects of SLC39A1 on U87 cell proliferation or apoptosis; RT-qPCR and western blot were used to detect its effects on the expression of MMP2\MMP9.

RESULTS

SLC39A1 has up-regulated expression in glioma tissues. High SLC39A1 expression predicted significantly worse survival. Univariate and multivariate analysis show that SLC39A1 independently indicated poor prognosis in patients with gliomas. The expression of SLC39A1 is significantly correlated with clinical pathological parameters such as Grade, IDH mutation status, and 1p19q codeletion status. In vitro experimental results show that SLC39A1 promotes proliferation of glioma cells, inhibits their apoptosis, and promotes expression of MMP2\MMP9. In addition, it may affect infiltration of immune cells into the glioma microenvironment.

CONCLUSION

SLC39A1 may serve as a new prognostic biomarker and potential target for treatment of gliomas.

Slc39a5-mediated zinc homeostasis plays an essential role in venous angiogenesis in zebrafish

Angiogenesis is a precise process mediated by a variety of signals and the environmental niche. Although the essential trace element zinc and its homeostasis are essential for maintaining proper cellular functions, whether zinc plays a role in angiogenesis is currently unknown. Using zebrafish embryos as a model system, we found that zinc treatment significantly increased the expression of the slc39a5 gene, which encodes the zinc transporter Slc39a5. Moreover, knocking down slc39a5 expression using either a morpholino or CRISPR/Cas9-mediated gene editing led to cardiac ischaemia and an accumulation of red blood cells in the caudal vein plexus (CVP), as well as delayed venous sprouting and fewer vascular loops in the CVP region during early development. Further analysis revealed significantly reduced proliferation and delayed cell migration in the caudal vein of slc39a5 morphants. At the mechanistic level, we found increased levels of systemic zinc in slc39a5-deficient embryos, and chelating zinc restored CVP development. In addition, we found that zinc overload in wild-type embryos leads to impaired CVP formation. Taken together, these results indicate that Slc39a5 plays a critical role in endothelial sprouting and migration in venous angiogenesis by regulating zinc homeostasis.

ZNF582 hypermethylation promotes metastasis of nasopharyngeal carcinoma by regulating the transcription of adhesion molecules Nectin-3 and NRXN3

Background

Epigenetic regulation plays an important role in the development and progression of nasopharyngeal carcinoma (NPC). However, the epigenetic mechanisms underlying NPC metastasis remains poorly understood. We aimed to find functional genes which regulate the metastasis of NPC and identify therapeutic targets for NPC treatment.

Methods

Bisulfite pyrosequencing was used to analyze zinc finger protein 582 (ZNF582) methylation in NPC tissues and cell lines. Quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR) and Western blotting were used to determine the expression of ZNF582. In vitro and in vivo experiments were performed to evaluate the biological function of ZNF582 in NPC. ZNF582‐targeting genes were identified by chromatin immunoprecipitation sequencing (ChIP‐seq) and were confirmed by ChIP‐qPCR and luciferase assay.

Results

ZNF582 promoter was hypermethylated in NPC, and both the mRNA and protein levels of ZNF582 were down‐regulated in NPC tissues and cell lines. The restoration of ZNF582 inhibited NPC migration, invasion, and metastasis, while the knockdown of ZNF582 promoted NPC migration, invasion, and metastasis in vitro and in vivo. ZNF582 directly regulated the transcription and expression of adhesion molecules Nectin‐3 and NRXN3. Both Nectin‐3 and NRXN3 were identified as functional targets of ZNF582, and the restoration or abrogation of these genes reversed the tumor suppressor effect of ZNF582 in NPC metastasis.

Conclusions

ZNF582 acts as a tumor suppressor gene in NPC by regulating the transcription and expression of adhesion molecules Nectin‐3 and NRXN3, which may provide novel therapeutic targets for NPC treatment.

GHR knockdown enhances the sensitivity of HCC cells to sorafenib

Sorafenib is approved for treatment of advanced hepatocellular carcinoma (HCC) by the Drug Administration. However, the efficacy of sorafenib has become very limited because most tumors have developed resistance to this drug. In this study, we found that sorafenib stimulated GHR expression in HCC cell lines. Thus, GHR might be linked to sorafenib resistance. To verify this hypothesis, we researched the roles of GHR knockdown and sorafenib combination in cell viability, apoptosis, cycle, and migration. The results showed that GHR blockage enhanced sorafenib blocking of cell cycle progression, leading to inhibition of this drug on HCC cell viability, and the improved promoting ability of sorafenib on cell apoptosis. In addition, it was found that GHR knockdown enhanced sorafenib inhibition of cell migration. The synergistic antitumor effects of sorafenib and GHR knockdown combination may be attributed to inhibition of PI3K/AKT/ERK1/2 signaling pathway. In conclusion, the findings suggest that GHR knockdown enhances the sensitivity of HCC cells to sorafenib. and the inactivation of PI3K/AKT/ERK1/2 signaling pathway may be the underlying mechanisms. This highlights the absence of GHR as a promising way to enhance sorafenib efficacy in HCC.

Nectin4 is a novel TIGIT ligand which combines checkpoint inhibition and tumor specificity

BACKGROUND

The use of checkpoint inhibitors has revolutionized cancer therapy. Unfortunately, these therapies often cause immune-related adverse effects, largely due to a lack of tumor specificity.

METHODS

We stained human natural killer cells using fusion proteins composed of the extracellular portion of various tumor markers fused to the Fc portion of human IgG1, and identified Nectin4 as a novel TIGIT ligand. Next, we generated a novel Nectin4 blocking antibody and demonstrated its efficacy as a checkpoint inhibitor in killing assays and in vivo.

RESULTS

We identify Nectin4 to be a novel ligand of TIGIT. We showed that, as opposed to all other known TIGIT ligands, which bind also additional receptors, Nectin4 interacts only with TIGIT. We show that the TIGIT-Nectin4 interaction inhibits natural killer cell activity, a critical part of the innate immune response. Finally, we developed blocking Nectin4 antibodies and demonstrated that they enhance tumor killing in vitro and in vivo.

CONCLUSION

We discovered that Nectin4 is a novel ligand for TIGIT and demonstrated that specific antibodies against it enhance tumor cell killing in vitro and in vivo. Since Nectin4 is expressed almost exclusively on tumor cells, our Nectin4-blocking antibodies represent a combination of cancer specificity and immune checkpoint activity, which may prove more effective and safe for cancer immunotherapy.

Loss of nectin-3 expression as a marker of tumor aggressiveness in pancreatic neuroendocrine tumor

Pancreatic neuroendocrine tumors (PanNETs) are rare, and prediction of aggressive characteristics, such as recurrence and metastasis and prognosis of PanNETs remain difficult. Nectins are cell adhesion molecules that regulate the formation of adherens and tight junctions. In this study, we investigated the clinicopathological significance of nectin-3 expression in patients with PanNETs. Immunohistochemical analysis of nectin-3 expression was performed on 78 cases of PanNET. Low nectin-3 expression in the membrane (positive ratio ≤25%) was observed in 62 cases (79.5%) and was significantly correlated with larger tumor size (>20 mm; P = 0.003), G2/G3 tumors (P = 0.025), higher Ki67 labeling index (≥3%; P = 0.009), lymphatic involvement (P = 0.047), advanced pT-factor (T2-T4; P = 0.003), lymph node metastasis (P = 0.006), advanced Union for International Cancer Control/American Joint Committee on Cancer-stage (Stage II-IV; P = 0.001), advanced ENETS stage (Stage IIa-IV; P = 0.001), nonfunctioning tumors (P = 0.002), and a shorter disease-free survival (P = 0.019). However, there was no significant correlation between nectin-3 expression in the membrane and/or cytoplasm and the clinicopathological parameters. The present results suggest that decreased nectin-3 expression in the membrane is associated with increased tumor aggressiveness of PanNETs. Clinically, immunohistochemical analysis of nectin-3 may help predict tumor aggressiveness for PanNETs.

The role of low density lipoprotein receptor-related protein 11 as a tumor promoter in cervical cancer

Background

It is unclear whether low density lipoprotein receptor-related protein 11 (LRP11), a newly found lipoprotein receptor regulatory protein, has the carcinogenic effects in cervical cancer.

Methods

Bioinformatics analysis, immunohistochemical (IHC) staining and evaluation, cell proliferation assay, flow cytometry, transwell migration and invasion assays, Western blotting, growth of LRP11-silenced cells in athymic nude mice were performed in this research.

Results

We found that LRP11 expression was higher in high-grade squamous intraepithelial lesions (HSIL) and cervical cancer tissue than in normal cervix, and high expression of LRP11 was associated with differentiation degree (P=0.0266), indicating poor prognosis (P=0.0210). The silencing of LRP11 in SiHa and CaSki cell lines inhibited cell proliferation, reduced migration and invasion and suppressed cell growth in nude mice, which possibly related to cell cycle protein regulation of CDK 2/4, cyclin D1/E1, MMP-2/9, and VEGF. Furthermore, LRP11 showed substantial positive correlation with P16 in vivo and in vitro.

Conclusion

LRP11 plays important roles in proliferation, migration and invasion, with the potential to be a useful prognostic marker and therapeutic target for patients with HSIL and cervical cancer.

Mimicking the tumor microenvironment: Fibroblasts reduce miR-29b expression and increase the motility of ovarian cancer cells in a co-culture model

Ovarian cancer (OC) is a highly prevalent gynecological malignancy worldwide. Throughout ovarian carcinogenesis, the crosstalk between cellular components of the microenvironment, including tumor cells and fibroblasts, is proposed to play critical roles in cancer progression. The dysregulation of microRNA expression is also a pronounced feature of the OC. The screening of microRNAs, mainly those involved in OC microenvironment, could have diagnostic and/or therapeutic potential for this malignancy. Thus, we assessed the influence of fibroblasts on microRNA expression and the motility of OC cells. To achieve this goal, SKOV-3 cancer cells were co-cultured with human normal fibroblasts derived from primary culture (FP-96). Cell viability, expression of tumor suppressor microRNAs and oncomiRs by RT-qPCR, cell migration by wound healing assay and analysis of MMP-2 activity by zymography were performed in SKOV-3 cells. Moreover, α-smooth muscle actin (α-SMA) expression was evaluated by Western blot in FP-96 fibroblasts. Notably, the co-culture downregulated the tumor suppressor miR-29b and increased migration of SKOV-3 cells. In addition, co-culture increased the activity of MMP-2, which is a miR-29 target, and accounted for extracellular matrix remodeling and augmented cellular motility. Concomitantly, the co-culture system induced α-SMA expression in FP-96 fibroblasts, the commonly expressed marker in cancer-associated fibroblasts (CAFs). Our findings suggest that the potential crosstalk between OC cells and fibroblasts in tumor microenvironment may play a key role in the progression of OC.