The Role and Mechanism of Nicotinamide Riboside in Oxidative Damage and a Fibrosis Model of Trabecular Meshwork Cells.

Purpose: To investigate the potential effects and mechanism of nicotinamide riboside (NR) on the oxidative stress and fibrosis model of human trabecular meshwork (HTM) cell line cells. Methods: HTM cells were pretreated with NR, followed by the induction of oxidative injury and fibrosis by hydrogen peroxide (H2O2) and TGF-ß2, respectively. Cell viability was tested using Hoechst staining and MTT assays, cell proliferation was assessed by EdU assay, and cell apoptosis was detected by flow cytometry and western blotting. DCFH-DA and DHE probes were used to measure the level of reactive oxygen species (ROS), and MitoTracker staining was used to measure the mitochondrial membrane potential (MMP). Fibrotic responses, including cell migration and deposition of extracellular matrix (ECM) proteins, were detected via Transwell assays, qRT-PCR, and immunoblotting. Results: NR pretreatment improved the viability, proliferation, and MMP of H2O2-treated HTM cells. Compared to cells treated solely with H2O2, HTM cells treated with both NR and H2O2, exhibited a reduced rate of apoptosis and generation of ROS. Compared with H2O2 pretreatment, NR pretreatment upregulated expression of the JAK2/Stat3 pathway but inhibited mitogen-activated protein kinase (MAPK) pathway expression. Moreover, 10-ng/mL TGF-ß2 promoted cell proliferation and migration, which were inhibited by NR pretreatment. Both qRT-PCR and immunoblotting showed that NR inhibited the expression of fibronectin in a TGF-ß2-induced fibrosis model. Conclusions: NR has a protective effect on oxidative stress and fibrosis in HTM cells, which may be related to the JAK2/Stat3 pathway and MAPK pathway. Translational Relevance: Our research provides the ongoing data for potential therapy of NAD+ precursors in glaucoma.

Interaction between visual impairment and subjective cognitive complaints on physical activity impairment in U.S. older adults: NHANES 2005-2008.

BACKGROUND/AIM: To investigate the independent relationships of visual impairment (VI) and Subjective cognitive complaints (SCC) with physical function impairment (PFI) and the interaction effect between VI and SCC on PFI in American older adults. METHODS: The data of this cross-sectional study was obtained from the 2005-2008 National Health and Examination Survey (NHANES) conducted in the United States. The VI criterion included both subjective self-reported eyesight conditions and objective visual acuity test results. The self-reported questionnaires were utilized to determine PFI and SCC. According to the survey design of NHANS, original data were weighted to produce nationally representative estimates. Both the unweighted original data and weighted estimates underwent analysis. Crude and adjusted logistic models were employed to assess the pairwise associations among VI, SCC, and PFI. To assess the interactive effect, measures such as the relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP), and synergy index (S) were calculated. RESULTS: A total of 2,710 subjects (weighted n = 38,966,687) aged 60 years or older were included. Compared with subjects without subjective visual impairment (SVI), those with SVI had a significant positive association with PFI [weighted OR (95%CI): 3.11 (2.25, 4.31)]. After multi-variable adjusting, the relationship remained significant [weighted OR (95%CI): 1.90 (1.32, 2.72)]. Similarly, those with objective visual impairment (OVI) were positively associated with the risk of PFI in the crude model [weighted OR (95%CI): 2.35 (1.53, 3.61)] and adjusted model [weighted OR (95%CI): 1.84 (1.07, 3.17)]. Moreover, we found the association of SCC with an increased risk of FPI [crude weighted OR (95%CI): 5.02 (3.40, 7.40); adjusted weighted OR (95%CI): 3.29 (2.01, 5.38)]. Ultimately, the additive interaction showed there was a significant positive interaction term between SVI and SCC on PFI, while OVI and SCC did not. CONCLUSION: Both VI and SCC were significantly associated with PFI in elder adults. Besides, there was a significant synergistic interaction between SVI and SCC on PFI, which indicated the improvement of SVI and SCC may be beneficial for the prevention of PFI. For the elderly, especially those with multiple disabilities, comprehensive and targeted approaches are imperative to foster their overall well-being and health.

Mutation analysis of RHO in patients with non-syndromic retinitis pigmentosa.

PURPOSE: To identify RHO mutations in patients with non-syndromic retinitis pigmentosa (NS-RP). METHODS: A total of 143 probands (46 family history and 97 sporadic cases) with NS-RP were recruited from Southeast China. The coding exons and adjacent intronic regions of RHO were PCR-amplified and sequenced by Sanger sequencing. The candidate variant was evaluated by the guidelines of American College of Medical Genetics and further validated through co-segregation analysis within the family. RESULTS: Five heterozygous mutations in RHO were detected in 5 out of 143 probands, where the frequency of RHO mutations in our cohort was approximately 3.5% (5/143) and 10.8% (5/46) for probands and families with NS-RP, respectively. Three known disease-causing mutations including c.C1030T (p.Q344X), c.C173G (p.T58R), and c.G266A (p.G89D) were identified in three unrelated families. The other two previously unreported mutations c.557C>A (p.S186X) and c.944delA (p.N315TfsX43) were confirmed in Family RP-087 and Family RP-139, respectively. These mutations co-segregated with available affected individuals in each family were not observed in the unaffected family members or in the 112 unrelated controls. CONCLUSIONS: This report expands the mutational spectrum of RHO gene associated with NS-RP and demonstrates the frequency of RP RHO mutations in Southeast Chinese populations.

Novel Variants of HPS6 Cause Suspected Ocular Albinism: A Report of 2 Cases and the Profile of HPS6 Variants.

INTRODUCTION: Hermansky-Pudlak syndrome (HPS) is a rare autosomal-recessive disease characterized by ocular albinism (OA) or oculocutaneous albinism (OCA), platelet dysfunction, and other symptoms. This study aimed to analyze the molecular defect in two Chinese families with suspected OA, as well as to investigate the profile of HPS6 variants and their genotype-phenotype correlations. METHODS: Seven members from two families were recruited and underwent clinical ophthalmologic examinations. The genomic DNA was extracted from peripheral blood leukocytes. Whole-exome sequencing was performed on the proband of family JX. The single coding exon of HPS6 was directly Sanger sequenced based on PCR amplification in all available family members. An additional 46 probands from families or sporadic cases with the pathogenic variants of HPS6 reported in the literature were reviewed. RESULTS: We identified two different compound heterozygous truncating variants of HPS6 in probands with suspected OA from two independent families. The proband of family JX had c.1674dup and c.503-504del variants, and the other proband from family CZ had a nonsense variant of c.1114C>T and a frameshift variant of c.1556del. Among them, c.1674dup and c.1556del variants in HPS6 have not been reported previously. Therefore, our patients were diagnosed as HPS6 disease by molecular diagnostics. In the retrospective cohort of HPS6 patients, we delineated the profile of HPS6 variants and revealed a significant overlap between CpG islands and the variants of HPS6, suggesting a potential link between DNA methylation and HPS6 variants. We also observed a spatial aggregation of the variants in 3D structure of HPS6 protein, implying the possible functional significance of these structural regions. In addition, we did not find any significant genotype-phenotype correlation of HPS6, and neither did we observe a correlation between the truncation length of the HPS6 protein and the phenotype of HPS6 disease. CONCLUSION: Our research expands the spectrum of HPS6 variants, providing a comprehensive delineation of their profile and systematically investigating genotype-phenotype correlations in HPS6. These findings could offer potentially valuable clues for investigating the molecular mechanism underlying HPS6 pathogenesis, as well as aiding the clinical diagnosis of HPS6 patients and improving disease prognosis.

Clinical observation of phacoemulsification under the low perfusion pattern and low negative pressure in patients with low corneal endothelial cell density.

BACKGROUND: To observe the safety and effect of phacoemulsification combined with intraocular lens (IOL) implantation in patients with low corneal endothelial cell density (CD) under the low perfusion pattern with low negative pressure. METHODS: In this retrospective case series study, a total of 16 patients (17 eyes) were studied. They had all been diagnosed with low corneal endothelial (CD) and cataracts in the First Affiliated Hospital of Fujian Medical University from December 2019 to October 2021. They underwent phacoemulsification combined with IOL implantation under the low perfusion pattern with low negative pressure. The variations of corneal endothelial( CD), coefficient of variation (CV) of the cell area, central corneal thickness (CCT), visual acuity, and intraocular pressure before and after the operation were observed and assessed. Then a paired t-test, repeated measures analysis of variance, and Pearson correlation analysis were adopted for data analysis. RESULTS: The mean intraocular pressure of the 17 eyes was 16.88 ± 6.47 mmHg before the operation and 14.41 ± 3.10 mmHg after the operation, showing a statistically significant difference of t = 2.222, and p = 0.041. Before the operation, the mean visual acuity was 0.16 ± 0.09, and after the operation, it was 0.45 ± 0.16, displaying a statistically significant difference of t = -9.917, p < 0.001. Before and after the operation, four of the 17 eyes had no detectable CD. The mean CD of the other 13 eyes at one month after the operation (644.308 ± 106.24 cells/mm2) was lower than that before the operation (709.62 ± 119.19 cells/mm2), and the differences were statistically significant (F = 20.044, p < 0.001). However, no statistically significant differences were found in the mean CV before the operation (31.23 ± 4.21), and at one month after the operation (32.62 ± 3.80; F = 2.130, p = 0.157). Moreover, the mean CCT of 14 eyes at one month after the operation (562.72 ± 27.82 µm) was larger than that before the operation (534.79 ± 24.69 µm). CONCLUSIONS: The low perfusion pattern with low negative pressure is safe and effective for corneal endothelial dysfunction patients complicated with cataracts.

FOSL2 promotes intertumoral infiltration of T cells and increases pathological complete response rates in locally advanced rectal cancer patients.

The outcome of neoadjuvant chemoradiotherapy (nCRT) remains highly unpredictable for individuals with locally advanced rectal cancer (LARC). We set out to characterize effective biomarkers that promote a pathological complete response (pCR). We quantified the abundances of 6483 high-confidence proteins in pre-nCRT biopsies of 58 LARC patients from two hospitals with pressure cycling technology (PCT)-assisted pulse data-independent acquisition (PulseDIA) mass spectrometry. Compared with non-pCR patients, pCR patients achieved long-term disease-free survival (DFS) and had higher tumor immune infiltration, especially CD8+ T cell infiltration, before nCRT. FOSL2 was selected as the candidate biomarker for predicting pCR and was found to be significantly upregulated in pCR patients, which was verified in another 54 pre-nCRT biopsies of LARC patients by immunohistochemistry. FOSL2 expression was able to predict pCR by multiple reaction monitoring (MRM) with high efficiency (Area under curve (AUC) = 0.939, specificity = 1.000, sensitivity = 0.850), and high FOSL2 expression was associated with long-term DFS (p = 0.044). When treated with simulated nCRT, FOSL2 sufficiency resulted in more significant inhibition of cell proliferation, and more significant promotion of cell cycle arrest and cell apoptosis. Moreover, CXCL10 secretion with abnormal cytosolic dsDNA accumulation was found in FOSL2-wildtype (FOSL2-WT) tumor cells over nCRT, which might elevate CD8+ T-cell infiltration and CD8+ T-cell-mediated cytotoxicity to promote nCRT-induced antitumor immunity. Our study revealed proteomic profiles in LARC patients before nCRT and highlighted immune activation in the tumors of patients who achieved pCR. We identified FOSL2 as a promising biomarker to predict pCR and promote long-term DFS by contributing to CD8+ T-cell infiltration.

Structure‒function‒pathogenicity analysis of C-terminal myocilin missense variants based on experiments and 3D models.

MYOC is a common pathogenic gene for primary open-angle glaucoma and encodes the protein named myocilin. Multiple MYOC variations have been found, with different clinical significance. However, the pathogenesis of glaucoma induced by MYOC mutations has not been fully clarified. Here, we analyze the molecular and cellular biological differences caused by multiple variant myocilins, including protein secretion characteristics, structural changes, subcellular localization, cellular autophagic activity and oxidative stress. Denaturing and nondenaturing electrophoresis showed myocilin to be a secreted protein with the tendency to self-oligomerize. The full-length myocilin and its C-terminal cleavage fragment are secreted. Secretion analysis of 23 variant myocilins indicated that secretion defects are closely related to the pathogenicity of MYOC variants. Structural analysis showed that the alteration of steric clash is associated with the secretion characteristics and pathogenicity of myocilin variants. Immunocytochemistry results demonstrated that mutated myocilins are retained in the endoplasmic reticulum and disrupt autophagy. MTT assay, MitoTracker staining, and DCFH-DA staining showed increased oxidative injury in cells expressing MYOC mutants. Taken together, MYOC mutations are able to induce cell dysfunction via secretion defects and intracellular accumulation resulting from steric clash alterations.

A novel immune-related lncRNA pair signature for prognostic prediction and immune response evaluation in gastric cancer: a bioinformatics and biological validation study.

BACKGROUND: Gastric cancer (GC), the most commonly diagnosed cancer worldwide with poor 5-year survival rate in advanced stages. Although immune-related and survival-related biomarkers, which typically comprise aberrantly expressed long non-coding RNAs (lncRNAs) and genes, have been identified, there are no reports of immune-related lncRNA pair (IRLP) signatures for GC. METHODS: In this study, we acquired lncRNA expression profiles from The Cancer Genome Atlas (TCGA) and used the least absolute shrinkage and selection operator (LASSO) Cox proportional hazards model (iteration = 1000) to develop a IRLP prognostic signature. The area under curve (AUC) was used to assess the prognosis predictive power. The multivariate Cox regression analysis was performed to identify whether this signature was an independent prognostic factor. The immune cell infiltration analysis was performed between the two risk groups. Last, molecular experiments were performed to explore LINC01082 is involved in the development of GC. RESULTS: We acquired lncRNA expression profiles and used the LASSO Cox model to develop an 18-IRLP signature with a strong prognostic predictive power. The 5-year AUC values of the training, validation, and overall TCGA datasets were 0.77, 0.86, and 0.80, respectively. The different prognostic outcomes between the high- and low-risk groups were determined using our 18-IRLP signature. Moreover, our 18-IRLP signature was an independent prognostic factor as per the multivariate Cox regression analysis, and showed better prognostic evaluation than the traditional TNM staging system as well as other clinical features. We also found differences in cancer-associated fibroblast and macrophage M2 infiltration and the expression of PD-L1, CTLA4, LAG3, and HLA were also observed between the two risk groups (P < 0.05). Analysis of biological functions revealed that target genes of the lncRNAs in the IRLP signature were enriched in focal adhesion and regulation of actin cytoskeleton. Finally, as one of significant candidates of IRLP signature, overexpression of LINC01082 suppressed the invasion ability of GC cells as well as PD-L1 expression profiles. CONCLUSIONS: Our novel 18-IRLP signature provides new insights regarding immunological biomarkers, imparts a better understanding of the tumor immune microenvironment, and can be used for predicting prognosis and evaluating immune response in GC.

HomeoboxC6 promotes metastasis by orchestrating the DKK1/Wnt/ß-catenin axis in right-sided colon cancer.

Patients with right-sided colon cancer (RCC) generally have a poorer prognosis than those with left-sided colon cancer (LCC). We previously found that homeobox C6 (HOXC6) was the most significantly upregulated gene in RCC compared to LCC. However, it remains unclear whether HOXC6 plays a role in tumor proliferation and metastasis. Our study aimed to explore the potential oncogenic role and the detailed molecular mechanism of HOXC6 in RCC. In this study, HOXC6 was validated to be overexpressed in RCC and associated with poor prognosis. Furthermore, overexpression of HOXC6 promoted the migration and invasion of colon cancer cells through inducing EMT by activating the Wnt/ß-catenin signaling pathway and inhibition of DKK1 secretion. Lastly, we preliminary explored the translational effect of HOXC6 and found that silencing of HOXC6 made HCT116 and HT29 cells more sensitive to irinotecan.

Mitochondrial quality control protects photoreceptors against oxidative stress in the H2O2-induced models of retinal degeneration diseases.

Retinal degeneration diseases (RDDs) are common and devastating eye diseases characterized by the degeneration of photoreceptors, which are highly associated with oxidative stress. Previous studies reported that mitochondrial dysfunction is associated with various neurodegenerative diseases. However, the role of mitochondrial proteostasis mainly regulated by mitophagy and mitochondrial unfolded protein response (mtUPR) in RDDs is unclear. We hypothesized that the mitochondrial proteostasis is neuroprotective against oxidative injury in RDDs. In this study, the data from our hydrogen peroxide (H2O2)-treated mouse retinal cone cell line (661w) model of RDDs showed that nicotinamide riboside (NR)-activated mitophagy increased the expression of LC3B II and PINK1, and promoted the co-localization of LC3 and mitochondria, as well as PINK1 and Parkin in the H2O2-treated 661w cells. However, the NR-induced mitophagy was remarkably reversed by chloroquine (CQ) and cyclosporine A (CsA), mitophagic inhibitors. In addition, doxycycline (DOX), an inducer of mtUPR, up-regulated the expression of HSP60 and CHOP, the key proteins of mtUPR. Activation of both mitophagy and mtUPR increased the cell viability and reduced the level of apoptosis and oxidative damage in the H2O2-treated 661w cells. Furthermore, both mitophagy and mtUPR played a protective effect on mitochondria by increasing mitochondrial membrane potential and maintaining mitochondrial mass. By contrast, the inhibition of mitophagy by CQ or CsA reversed the beneficial effect of mitophagy in the H2O2-treated 661w cells. Together, our study suggests that the mitophagy and mtUPR pathways may serve as new therapeutic targets to delay the progression of RDDs through enhancing mitochondrial proteostasis.

Protective Effects of Nicotinamide Riboside on H2O2-induced Oxidative Damage in Lens Epithelial Cells.

Purpose: To investigate the protective effects of nicotinamide riboside (NR) on oxidative damage in hydrogen peroxide (H2O2)-exposed human lens epithelial cell lines (SRA01/04) and the possible mechanisms underlying its protective effects.Materials and methods: SRA01/04 cells were divided into three groups: the control (CON) group, model (H2O2) group and treatment (NR+H2O2) group. Superoxide dismutase (SOD), catalase (CAT) and total glutathione (GSH) levels were detected to evaluate oxidative damage induced by different concentrations of H2O2 in SRA01/04 cells. After SRA01/04 cells were treated with NR and/or H2O2, cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Hoechst staining, cell apoptosis was analysed using flow cytometry, reactive oxygen species (ROS) were measured with the DCFH-DA probe, and mitochondria were stained with MitoTracker to measure the mitochondrial membrane potential (MMP). In addition, western blotting was performed to detect the levels of proteins associated with apoptosis and related signalling pathways.Results: H2O2 induced oxidative damage in SRA01/04 cells by inhibiting the activity of SOD and CAT and reducing total GSH levels. Treatment of SRA01/04 cells with NR significantly increased cell viability and reduced cell apoptosis and ROS generation, whereas SOD and CAT activities and total GSH and MMP levels were improved by the NR treatment in an H2O2-exposed cell model. Furthermore, NR significantly inhibited the activation of the MAPK pathway but promoted activation of the JAK2/Stat3 pathway compared with the model group.Conclusions: NR may alleviate oxidative damage by targeting the MAPK and JAK2/Stat3 pathways in H2O2-treated SRA01/04 cells. NR may represent anovel drug for preventing or treating cataracts.

Reducing Frequency of Emergency Department and Inpatient Visits Through Focused Case Management.

PURPOSE OF STUDY: To evaluate whether the Oklahoma State University (OSU) Health Access Network's (HAN's) case management program is effective in reducing the attendance of frequent users to the emergency department (ED) and inpatient department. PRIMARY PRACTICE SETTING: This is a 2-year retrospective pre/post-case management analysis. Emergency department usage data from 2013 to 2016 of the OSU HAN contracted clinics are used in this study. This study involves case management interventions for high ED users and high-risk patients. The patients in the study must be enrolled in SoonerCare choice to be case managed. METHODOLOGY AND SAMPLE: Patients who visited the ED 3 times or more in 12 months prior to their HAN enrollment and patients with 12 months of data preenrollment and postenrollment were included in the study. A historical control was used to compare ED and inpatient use per patient per month pre- and post-HAN case management. Chi-square and Wilcoxon's signed-rank tests were used to assess the data. RESULTS: A total of 29 patients met the inclusion criteria. The number of ED and inpatient visits was reduced after HAN intervention (181 vs. 110, p < .001; 35 vs. 11, p < .001). The ED and inpatient use per patient per month reduced significantly from 0.52 to 0.31 (p < .001) and 0.10 to 0.03 (p < .01), respectively. IMPLICATIONS FOR CASE MANAGEMENT PRACTICE: This study suggests that continuous case management and implementation of various care plans with frequent follow-up are effective in reducing the cost of care and subsequent ED and inpatient visits.

A recognition survey of granular corneal dystrophy type 2 genetic detection in China.

AIM: To evaluate the feasibility of promoting genetic detection for granular corneal dystrophy type 2 (GCD2) by a questionnaire conducted among citizens in five cities in China. METHODS: The data were collected by questionnaire, and analyzed by Chi-square test and one-tailed t test in IBM SPSS statistics. RESULTS: Based on the survey data on the awareness of GCD2 genetic detection in this study and the positive predictive analysis report of the citizens in five cities in China, the vast majority (84.2%) of respondents had never heard of it and did not know that GCD2 patients have been prohibited from performing excimer surgery that can deteriorate GCD2 patients' condition even leading to blindness. Though 3.4% of patients understood GCD2 very much, they have no idea that GCD2 could not be 100% accuracy diagnosed by the conventional inspection methods. CONCLUSION: It is feasible and necessary to use GCD2 genetic detection as an excimer preoperative examination project. In order to promote the development of detection project, a few improvements should be carried out in terms of the promoting efforts, costs, and research progress.

Application of exosomes as liquid biopsy in clinical diagnosis.

Liquid biopsy refers to the sampling and molecular analysis of the biofluids of circulating tumor cells, extracellular vesicles, nucleic acids, and so forth. Exosomes are small extracellular vesicles with sizes between 30-150 nm. They are secreted by multivesicular bodies through exocytosis in live cells and can participate in intercellular communication due to their contents, including nucleic acids, proteins, and lipids. Herein, we investigate publication frequencies on exosomes over the past 10 years, and review recent clinical studies on liquid biopsy of exosomes in the fields of oncology, pregnancy disorders, cardiovascular diseases, and organ transplantation. We also describe the advantages of exosomes as an effective liquid biopsy tool and the progression of exosome extraction methods. Finally, we depict the commercial development of exosome research and discuss the future role of exosomes in liquid biopsy.

A circulating extracellular vesicles-based novel screening tool for colorectal cancer revealed by shotgun and data-independent acquisition mass spectrometry.

Background: Early screening for colorectal cancer (CRC) is essential to improve its prognosis. Liquid biopsies are increasingly being considered for diagnosing cancer due to low invasiveness and high reproducibility. In addition, circulating extracellular vesicles (crEVs, extracellular vesicles isolated from plasma) expressing tumour-specific proteins are potential biomarkers for various cancers. Here, we present a data-independent acquisition (DIA)-mass spectrometry (MS)-based diagnostic method for liquid biopsies. Methods: Extracellular vesicles (EVs) were isolated from culture supernatants of human CRC cell lines, and plasma of patients with CRC at different tumour stages, by overnight ultracentrifugation coupled with sucrose density gradient centrifugation. Tumour-specific EV proteins were prioritized using Tandem Mass Tag (TMT)-based shotgun proteomics and phosphoproteomics. The results were verified in a second independent cohort and a mouse tumour-bearing model using Western blotting (WB). The candidate biomarkers were further validated in a third cohort by DIA-MS. Finally, the DIA-MS methodology was accelerated to permit high-throughput detection of EV biomarkers in another independent cohort of patients with CRC and healthy controls. Results: High levels of total and phosphorylated fibronectin 1 (FN1) in crEVs, haptoglobin (HP), S100A9 and fibrinogen α chain (FGA) were significantly associated with cancer progression. FGA was the most dominant biomarker candidate. Analysis of the human CRC cell lines and the mouse model indicated that FGA+ crEVs were likely released by CRC cells. Furthermore, fast DIA-MS and parallel reaction monitoring (PRM)-MS both confirmed that FGA+ crEVs could distinguish colon adenoma with an area of curve (AUC) in the receiver operating characteristic (ROC) curve of 0.949 and patients with CRC (AUC of ROC is 1.000) from healthy individuals. The performance outperformed conventional tumour biomarkers. The DIA-MS quantification of FGA+ crEVs among three groups agreed with that from PRM-MS. Conclusion: DIA-MS detection of FGA+ crEVs is a potential rapid and non-invasive screening tool to identify early stage CRC. Abbreviations: FGA: fibrinogen α chain; CRC: colorectal cancer; crEVs: circulating extracellular vesicles; EV: extracellular vesicles;MS: mass spectrometry; WB: Western blotting; ROC: receiver operating characteristic; PRM: Parallel Reaction Monitoring; GPC1: Glypican-1; GO: Gene ontology; TEM: transmission electron microscopy; FN1: Fibronectin 1; HP: haptoglobin; TMT: Tandem Mass Tag; LC-MS/MS: liquid chromatography coupled to tandem mass spectrometry; DIA: data-independent acquisition; DDA: data-dependent acquisition; CiRT: Common internal Retention Time standards;AGC: Automatic gain control; AUC: area under curve.

Targeting the NAD+ salvage pathway suppresses APC mutation-driven colorectal cancer growth and Wnt/ß-catenin signaling via increasing Axin level.

BACKGROUND: The role and mechanism of the nicotinamide adenine dinucleotide (NAD+) salvage pathway in cancer cell proliferation is poorly understood. Nicotinamide phosphoribosyltransferase (NAMPT), which converts nicotinamide into NAD+, is the rate-limiting enzyme in the NAD+ salvage pathway. Here, we assessed the role of NAMPT in the proliferation of colorectal cancer. METHODS: Real-time PCR, immunohistochemistry, western blotting, and analyses of datasets from Oncomine and Gene Expression Omnibus were conducted to assess the expression of NAMPT at the mRNA and protein levels in colorectal cancer. The Kaplan Meier plotter online tool was used to evaluate the prognostic role of NAMPT. Knockdown of NAMPT was performed to assess the role of NAMPT in colorectal cancer cell proliferation and tumorigenesis both in vitro and in vivo. Overexpression of NAMPT was used to evaluate impact of NAMPT on colorectal cancer cell proliferation in vitro. NAD+ quantitation, immunofluorescence, dual luciferase assay and western blot were used to explore the mechanism of colorectal cancer proliferation. Transwell migration and invasion assays were conducted to assess the role of NAMPT in cell migration and invasion abilities of colorectal cancer cells. RESULTS: Our study indicated that the inhibition of NAMPT decreased proliferation capacity of colorectal cancer cells both in vitro and in vivo. Conversely, overexpression of NAMPT could promote cell proliferation in vitro. NAMPT inhibition induced ß-catenin degradation by increasing Axin expression levels; this resulted in the inhibition of Wnt/ß-catenin signaling and cell proliferation in colorectal cancer. The addition of nicotinamide mononucleotide, the enzymatic product of NAMPT, effectively reversed ß-catenin protein degradation and inhibited growth. Similarly, the knockdown of Axin also decreased the cell death induced by the inhibition of NAMPT. In addition, we showed that colorectal cancer tissues harbored significantly higher levels of NAMPT than the levels harbored by paired normal tissues, especially in colorectal cancer stages I and II. And the overexpression of NAMPT was associated with unfavorable survival results. CONCLUSIONS: Our findings reveal that NAMPT plays an important role in colorectal cancer proliferation via Wnt/ß-catenin pathway, which could have vital implications for the diagnosis, prognosis and treatment of colorectal cancer.

Significant prognostic values of differentially expressed-aberrantly methylated hub genes in breast cancer.

Introduction: Abnormal status of gene expression plays an important role in tumorigenesis, progression and metastasis of breast cancer. Mechanisms of gene silence or activation were varied. Methylation of genes may contribute to alteration of gene expression. This study aimed to identify differentially expressed hub genes which may be regulated by DNA methylation and evaluate their prognostic value in breast cancer by bioinformatic analysis. Methods: GEO2R was used to obtain expression microarray data from GSE54002, GSE65194 and methylation microarray data from GSE20713, GSE32393. Differentially expressed-aberrantly methylated genes were identified by FunRich. Biological function and pathway enrichment analysis were conducted by DAVID. PPI network was constructed by STRING and hub genes was sorted by Cytoscape. Expression and DNA methylation of hub genes was validated by UALCAN and MethHC. Clinical outcome analysis of hub genes was performed by Kaplan Meier-plotter database for breast cancer. IHC was performed to analyze protein levels of EXO1 and Kaplan-Meier was used for survival analysis. Results: 677 upregulated-hypomethylated and 361 downregulated-hypermethylated genes were obtained from GSE54002, GSE65194, GSE20713 and GSE32393 by GEO2R and FunRich. The most significant biological process, cellular component, molecular function enriched and pathway for upregulated-hypomethylated genes were viral process, cytoplasm, protein binding and cell cycle respectively. For downregulated-hypermethylated genes, the result was peptidyl-tyrosine phosphorylation, plasma membrane, transmembrane receptor protein tyrosine kinase activity and Rap1 signaling pathway (All p< 0.05). 12 hub genes (TOP2A, MAD2L1, FEN1, EPRS, EXO1, MCM4, PTTG1, RRM2, PSMD14, CDKN3, H2AFZ, CCNE2) were sorted from 677 upregulated-hypomethylated genes. 4 hub genes (EGFR, FGF2, BCL2, PIK3R1) were sorted from 361 downregulated-hypermethylated genes. Differential expression of 16 hub genes was validated in UALCAN database (p<0.05). 7 in 12 upregulated-hypomethylated and 2 in 4 downregulated-hypermethylated hub genes were confirmed to be significantly hypomethylated or hypermethylated in breast cancer using MethHC database (p<0.05). Finally, 12 upregulated hub genes (TOP2A, MAD2L1, FEN1, EPRS, EXO1, MCM4, PTTG1, RRM2, PSMD14, CDKN3, H2AFZ, CCNE2) and 3 downregulated genes (FGF2, BCL2, PIK3R1) contributed to significant unfavorable clinical outcome in breast cancer (p<0.05). High expression level of EXO1 protein was significantly associated with poor OS in breast cancer patients (p=0.03). Conclusion: Overexpression of TOP2A, MAD2L1, FEN1, EPRS, EXO1, MCM4, PTTG1, RRM2, PSMD14, CDKN3, H2AFZ, CCNE2 and downregulation of FGF2, BCL2, PIK3R1 might serve as diagnosis and poor prognosis biomarkers in breast cancer by more research validation. EXO1 was identified as an individual unfavorable prognostic factor. Methylation might be one of the major causes leading to abnormal expression of those genes. Functional analysis and pathway enrichment analysis of those genes would provide novel ideas for breast cancer research.