Upregulation of NETO2 gene in colorectal cancer

TYMSOS-miR-101-3p-NETO2 axis promotes osteosarcoma progression

BACKGROUND

Osteosarcoma (OS) is a type of bone cancer most often affects pre-teens and teens, but it is still a rare disorder. Neuropilin and tolloid-like 2 (NETO2) has been reported to promote OS progression, but its upstream mechanism in OS cells remains obscure.

METHODS

Quantitative real-time PCR (RT-qPCR) and Western blot were conducted to examine RNA and protein levels, separately. Functional assays were performed to assess the impact of NETO2 on OS cell malignancy. Moreover, bioinformatics analyses and mechanism experiments were performed to identify the upstream mechanism of NETO2 in OS cells.

RESULTS

Functionally, NETO2 depletion repressed cell proliferation, migration and invasion as well as epithelial-mesenchymal transition (EMT) but triggered the apoptosis of OS cells. NETO2 is directly targeted and negatively regulated by microRNA-101-3p (miR-101-3p). Mechanically, miR-101-3p could combine with long noncoding RNA (lncRNA) TYMS opposite strand RNA (TYMSOS) in OS cells. In addition, our study proved that TYMSOS promotes the malignancy of OS via elevating NETO2 expression as miR-101-3p sponge.

CONCLUSION

TYMSOS-miR-101-3p-NETO2 axis promotes the malignant behaviors of OS cells, which might offer a novel sight for OS treatment.

Glioma-derived LRIG3 interacts with NETO2 in tumor-associated macrophages to modulate microenvironment and suppress tumor growth

Tumor-associated macrophages (TAMs) account for 30-50% of glioma microenvironment. The interaction between glioma tumor cells and TAMs can promote tumor progression, but the intrinsic mechanisms remain unclear. Herein, we reported that soluble LRIG3 (sLRIG3) derived from glioma tumor cells can block the M2 polarization of TAMs via interacting with NETO2, thus suppressing GBM malignant progression. The expression or activity of ADAM17 in glioma cells was positively correlated with the expression of sLRIG3 in cell supernatant. Soluble LRIG3 can suppress the M2-like polarity transformation of TAMs and inhibit the growth of tumor. High expression of LRIG3 predicts a good prognosis in patients with glioma. Mass spectrometry and Co-immunoprecipitation showed that sLRIG3 interacts with the CUB1 domain of NETO2 in TAMs. Silencing or knockout of NETO2 could block the effect of sLRIG3, which inhibited the M2-like polarity transformation of TAMs and promoted GBM tumor growth. However, overexpressing His-target NETO2 with CUB1 deletion mutation does not fully recover the suppressive effects of sLRIG3 on the TAM M2-polarization in NETO2-Knockout TAMs. Our study revealed vital molecular crosstalk between GBM tumor cells and TAMs. Glioma cells mediated the M2 polarization of TAM through the sLRIG3-NETO2 pathway and inhibited the progression of GBM, suggesting that sLRIG3-NETO2 may be a potential target for GBM treatment.

NETO2 Is Deregulated in Breast, Prostate, and Colorectal Cancer and Participates in Cellular Signaling

The NETO2 gene (neuropilin and tolloid-like 2) encodes a protein that acts as an accessory subunit of kainate receptors and is predominantly expressed in the brain. Upregulation of NETO2 has been observed in several tumors; however, its role in tumorigenesis remains unclear. In this study, we investigated NETO2 expression in breast, prostate, and colorectal cancer using quantitative PCR (qPCR), as well as the effect of shRNA-mediated NETO2 silencing on transcriptome changes in colorectal cancer cells. In the investigated tumors, we observed both increased and decreased NETO2 mRNA levels, presenting no correlation with the main clinicopathological characteristics. In HCT116 cells, NETO2 knockdown resulted in the differential expression of 17 genes and 2 long non-coding RNAs (lncRNAs), associated with the upregulation of circadian rhythm and downregulation of several cancer-associated pathways, including Wnt, transforming growth factor (TGF)-β, Janus kinase (JAK)-signal transducer and activator of transcription (STAT), mitogen-activated protein kinase (MAPK), and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathways. Furthermore, we demonstrated the possibility to utilize a novel model organism, short-lived fish Nothobranchius furzeri, for evaluating NETO2 functions. The ortholog neto2b in N. furzeri demonstrated a high similarity in nucleotide and amino acid sequences with human NETO2, as well as was characterized by stable expression in various fish tissues. Collectively, our findings demonstrate the deregulation of NETO2 in the breast, prostate, and colorectal cancer and its participation in the tumor development primarily through cellular signaling.

MiR-581/SMAD7 Axis Contributes to Colorectal Cancer Metastasis: A Bioinformatic and Experimental Validation-Based Study

Metastasis is a well-known poor prognostic factor and primary cause of mortality in patients with colorectal cancer (CRC). Recently, with the progress of high through-put sequencing, aberrantly expressed non-coding RNAs (ncRNAs) were found to participate in the initiation and development of cancer. However, the mechanisms of ncRNA-mediated regulation of metastasis in CRC remain largely unknown. In this study, we systematically analyzed the expression network of microRNAs (miRNAs) and genes in CRC metastasis using bioinformatics, and discovered that the miR-581/SMAD7 axis could be a potential factor that drives CRC metastasis. A dual luciferase report assay and protein analysis confirmed the binding relationship between miR-581 and SMAD7. Further functional assays revealed that miR-581 inhibition could suppress cell proliferation and induce apoptosis in SW480 cells. Up-regulation or down-regulation of miR-581 could both affect cell invasion capacity and modulate epithelial to mesenchymal transition (EMT) via a SMAD7/TGFβ signaling pathway. In conclusion, our findings elucidated that miR-581/SMAD7 could be essential for CRC metastasis, and may serve as a potential therapeutic target for CRC patients.

Pilot deep RNA sequencing of worker blood samples from Singapore printing industry for occupational risk assessment

Several engineered nanomaterials (ENMs) are used in toner-based printing equipment (TPE) including laser printers and photocopiers to improve toner performance. High concentration of airborne nanoparticles due to TPE emissions has been documented in copy centers and chamber studies. Recent animal inhalation studies by our group suggested exposure to laser printer-emitted nanoparticles (PEPs) increased cardiovascular risk by impairing ventricular performance and inducing hypertension and arrhythmia, consistent with global transcriptomic and metabolomic profiling results. There has been no genome-wide transcriptomic analysis of workers exposed to TPE emissions to systematically assess the occupational exposure health risks. In this pilot study, deep RNA sequencing of blood samples of workers in two printing companies in Singapore was performed. The genome-scale analysis of the blood samples from TPE exposed workers revealed perturbed transcriptional activities related to inflammatory and immune responses, metabolism, cardiovascular impairment, neurological diseases, oxidative stress, physical morphogenesis/deformation, and cancer, when compared with the control peers (office workers). Many of these disease risks associated with particle inhalation exposures in such work environments were consistent with the observation from the PEPs rat inhalation studies. In particular, the cell adhesion molecules (CAMs) was a top significantly perturbed pathway in blood samples from exposed workers compared with the office workers in both companies. The protein expression of sICAM was verified in plasma of exposed workers, showing a positive correlation with daily average nanoparticle concentration in indoor air measured in these two companies. Larger scale genomic and molecular epidemiology studies in copier operators are warranted in order to assess potential risks from such particulate matter exposures.

Effect of PIERCE1 on colorectal cancer

Colorectal cancer is the second most lethal cancer type across all ages and sexes, the many mechanisms of which are still currently being further elucidated. PIERCE1 has been known to be involved in the cell cycle and proliferation, the expression of which is regulated by stress conditions in a p53-dependent manner. Through a database search, we found that PIERCE1 was significantly augmented in patients with colorectal carcinoma compared to normal samples, suggesting its possible role in tumor regulation. Recently, PIERCE1 has also been reported to increase proliferation of a liver cancer cell line, indicating its possible role as an oncogene. To examine its relevance to tumorigenesis, such as whether it has either oncogenic or tumor suppressive function, PIERCE1 was knocked down and overexpressed in several colorectal cancer cell lines and mice, respectively. To evaluate the roles of Pierce1 in vivo, we established a Pierce1 transgenic (TG) mouse model and then administered azoxymethane with dextran sodium sulfate (DSS) to induce colorectal carcinogenesis via promoting mutations in Apc and Kras. Nonetheless, PIERCE1 depletion in these cell lines showed no significant change in cell growth. AOM/DSS-treated Pierce1 TG mice were comparable with respect to colon lengths, the number of polyps, and tumor sizes to those of the control mice. These results implicate that PIERCE1 does not play an oncogenic or tumor suppressive role in AOM/DSS-induced colorectal cancer.

Differentially Expressed Genes Associated With Prognosis in Locally Advanced Lymph Node-Negative Prostate Cancer

Older age is one of the main risk factors for cancer development. The incidence of prostate cancer, as a multifactorial disease, also depends upon demographic factors, race, and genetic predisposition. Prostate cancer most frequently occurs in men over 60 years of age, indicating a clear association between older age and disease onset. Carcinogenesis is followed by the deregulation of many genes, and some of these changes could serve as biomarkers for diagnosis, prognosis, prediction of drug therapy efficacy, as well as possible therapeutic targets. We have performed a bioinformatic analysis of a The Cancer Genome Atlas (TCGA) data and RNA-Seq profiling of a Russian patient cohort to reveal prognostic markers of locally advanced lymph node-negative prostate cancer (lymph node-negative LAPC). We also aimed to identify markers of the most common molecular subtype of prostate cancer carrying a fusion transcript TMPRSS2-ERG. We have found several genes that were differently expressed between the favorable and unfavorable prognosis groups and involved in the enriched KEGG pathways based on the TCGA (B4GALNT4, PTK6, and CHAT) and Russian patient cohort data (AKR1C1 and AKR1C3). Additionally, we revealed such genes for the TMPRSS2-ERG prostate cancer molecular subtype (B4GALNT4, ASRGL1, MYBPC1, RGS11, SLC6A14, GALNT13, and ST6GALNAC1). Obtained results contribute to a better understanding of the molecular mechanisms behind prostate cancer progression and could be used for further development of the LAPC prognosis marker panel.

NETO2 promotes pancreatic cancer cell proliferation, invasion and migration via activation of the STAT3 signaling pathway

Purpose: The biological functions of neuropilin and tolloid-like 2 (NETO2) in the progression of pancreatic cancer remained unexplored. We aimed to investigate the biological roles and underlying molecular mechanisms of NETO2 in pancreatic cancer.

Materials and methods: Thirty paired pancreatic tumor tissue samples and corresponding nontumor tissues were obtained from 30 pancreatic cancer patients who did not receive preoperative chemotherapy or radiotherapy. The changes in multiple cellular functions associated with tumor progression were assessed after NETO2 knockdown/overexpression in pancreatic cancer cell lines. Additionally, a mouse-xenograft model was developed to verify the in vitro results.

Results:NETO2 was upregulated in pancreatic tumor tissues. Elevated expression of NETO2 was not only associated with an advanced tumor stage, but was also a prediction of poor prognosis for pancreatic cancer patients. Knockdown of NETO2 in pancreatic cancer cell lines arrested the cell cycle and inhibited cell proliferation, colony formation, invasion, and migration; in contrast, overexpression of NETO2 had an opposite effect on all of these parameters. A STAT3 specific inhibitor, cryptotanshinone, reversed the tumor-promoting effects induced by NETO2 overexpression in pancreatic cancer. Western blot analysis showed that invasion and migration were closely related to epithelial–mesenchymal transition, and that the STAT3 signaling pathway was involved in NETO2-mediated oncogenic transformation in pancreatic cancer cells. Furthermore, NETO2 knockdown significantly inhibited the growth of pancreatic tumor xenografts in nude mice.

Conclusion:NETO2 has an important role in the progression and metastasis of pancreatic cancer and could serve as a novel candidate for targeted therapy of pancreatic cancer.

Reducing NETO2 expression prevents human nasopharyngeal carcinoma (NPC) progression by suppressing metastasis and inducing apoptosis

Nasopharyngeal carcinoma (NPC), the most common cancer in head and neck regions, is a serious health problem worldwide. Neuropilin and tolloid-like 2 (NETO2), a member of the subfamily of CUB domain and LDLa-containing proteins, has been suggested to be involved in tumor progression. Nevertheless, little is known about the function and molecular mechanism of NETO2 in NPC progression. In the study, NETO2 was found to be significantly up-regulated in clinical tissues and NPC cell lines. NETO2 expression was positively correlated with tumor size. NETO2 knockdown inhibited cell proliferation, migration and invasion in NPC cell lines. Significantly, NETO2 knockdown promoted the radiotherapy in vitro, as evidenced by the further reduced cell proliferation and metastasis in NPC cells using 3-[4, 5-dimethylthiazol-2-yl]-2, 5 diphenyl tetrazolium bromide (MTT), colony formation and transwell analysis. In addition, NETO2 inhibition markedly induced apoptosis in NPC cells through activating Caspase-3 signaling. Also, the knockdown of NETO2 obviously promoted the efficacy of radiotherapy in apoptosis induction, along with higher expression of cleaved Caspase-3. NETO2 knockdown-triggered apoptosis in NPC cells were considerably diminished by Caspase-3 inactivation, demonstrating the essential role of Caspase-3 in NETO2-regulated NPC development. Moreover, in vivo experiments suggested that NETO2 knockdown promoted radiation-induced tumor growth suppression in the absence of significant side effects. Collectively, reducing NETO2 expression might elevate the efficiency of radiotherapy in NPC patients.

Mutational load in carotid body tumor

Background

Carotid body tumor (CBT) is a rare neoplasm arising from paraganglion located near the bifurcation of the carotid artery. There is great intra-tumor heterogeneity, and CBT development could be associated with both germline and somatic allelic variants. Studies on the molecular genetics of CBT are limited, and the molecular mechanisms of its pathogenesis are not fully understood. This work is focused on the estimation of mutational load (ML) in CBT.

Methods

Using the NextSeq 500 platform, we performed exome sequencing of tumors with matched lymph node tissues and peripheral blood obtained from six patients with CBT. To obtain reliable results in tumors with low ML, we developed and successfully applied a complex approach for the analysis of sequencing data. ML was evaluated as the number of somatic variants per megabase (Mb) of the target regions covered by the Illumina TruSeq Exome Library Prep Kit.

Results

The ML in CBT varied in the range of 0.09–0.28/Mb. Additionally, we identified several pathogenic/likely pathogenic somatic and germline allelic variants across six patients studied (including TP53 variants).

Conclusions

Using the developed approach, we estimated the ML in CBT, which is much lower than in common malignant tumors. Identified variants in known paraganglioma/pheochromocytoma-causative genes and novel genes could be associated with the pathogenesis of CBT. The obtained results expand our knowledge of the mutation process in CBT as well as the biology of tumor development.

NETO2 promotes invasion and metastasis of gastric cancer cells via activation of PI3K/Akt/NF-κB/Snail axis and predicts outcome of the patients

Aberrant expression of neuropilin and tolloid-like 2 (NETO2) has been observed during the progression of some human carcinomas. However, the expression pattern and clinical relevance of NETO2 in gastric cancer (GC) remain to be elucidated. In this study, we found that NETO2 expression was higher in GC tissues compared with paired non-cancerous tissues. Moreover, the expression of NETO2 was positively correlated with clinical stage, invasion depth, lymph node metastasis, and tumor size, but inversely correlated with overall and disease-free survival rates. Cox regression analysis identified NETO2 as an independent prognostic indicator for GC patients. Overexpression of NETO2 facilitated migration and invasion of GC cells in vitro and metastasis in vivo in association with induction of epithelial-mesenchymal transition. Conversely, knockdown of NETO2 had the opposite effects. Mechanistically, silencing NETO2 reduced the phosphorylation of PI3K, AKT, and NF-κB p65 as well as the expression of Snail, whereas NETO2 overexpression achieved the opposite results. Furthermore, we identified TNFRSF12A as a mediator for NETO2 to activate PI3K/AKT/NF-κB/Snail axis. Collectively, our results demonstrate that NETO2 promotes invasion and metastasis of GC cells and represents a novel prognostic indicator as well as a potential therapeutic target in GC.