Secernin-1 contributes to colon cancer progression through enhancing matrix metalloproteinase-2/9 exocytosis

Genetic correlation, shared loci, but no causality between bipolar disorder and inflammatory bowel disease: A genome-wide pleiotropic analysis

BACKGROUND AND AIMS

The comorbidity between bipolar disorder (BD) and inflammatory bowel disease (IBD) has been widely reported in observational studies. However, unclear whether this comorbidity reflects a shared genetic architecture.

METHODS

Leveraging large-scale genome-wide association study (GWAS) summary statistics of BD, IBD and its subtypes, ulcerative colitis (UC) and Crohn's disease (CD), we performed a genome-wide pleiotropic analysis to estimate heritability and genetic correlation, identify pleiotropy loci/genes, and explore the shared biological pathway. Mendelian randomization (MR) studies were subsequently employed to infer whether the potential causal relationship is present.

RESULTS

We found a positive significant genetic correlation between BD and IBD (rg = 0.10, P = 7.00 × 10-4), UC (rg = 0.09, P = 2.90 × 10-3), CD (rg = 0.08, P = 6.10 × 10-3). In cross-trait meta-analysis, a total of 29, 24, and 23 independent SNPs passed the threshold for significant association between BD and IBD, UC, and CD, respectively. We identified five novel pleiotropy genes including ZDHHC2, SCRN1, INPP4B, C1orf123, and BRD3 in both BD and IBD, as well as in its subtypes UC and CD. Pathway enrichment analyses revealed that those pleiotropy genes were mainly enriched in several immune-related signal transduction pathways and cerebral disease-related pathways. MR analyses provided no evidence for a causal relationship between BD and IBD.

CONCLUSION

Our findings corroborated that shared genetic basis and common biological pathways may explain the comorbidity of BD and IBD. These findings further our understanding of shared genetic mechanisms underlying BD and IBD, and potentially provide points of intervention that may allow the development of new therapies for these co-occurrent disorders.

Knockdown of Secernin 1 inhibit cell invasion and migration by activating the TGF-β/Smad3 pathway in oral squamous cell carcinomas

Secernin-1 (SCRN1) is a regulator of exocytosis in mast cells. Recently, SCRN1 was reported to be correlated with the prognosis of colorectal cancer and gastric cancer, but its functional effects on oral squamous cell carcinoma (OSCC) remain unclear. Our aim was to explore the expression pattern and the migration and invasion effects of the newly identified SCRN1 in OSCC. Western blotting (WB) was performed to measure SCRN1 expression in human OSCC tissue samples and OSCC cell lines. The effects of SCRN1 on OSCC cell proliferation, invasion and migration were analyzed by cell counting kit-8 and Transwell assays. The expression levels of TGF-β, Smad3 and phosphorylated Smad3 (p-Smad3) were measured by WB. The secretion of matrix metalloproteinase (MMP)-2 and MMP-9 was determined by the enzyme-linked immunosorbent assay. The expression of SCRN1 was significantly elevated in OSCC tissues and cell lines. SCRN1 knockdown reduced the expression of TGF-β and p-Smad3 in OSCC cells. TGF-β stimulation promoted proliferation, invasion and migration and enhanced the expression of p-Smad3 and the secretion of MMP9 in SCRN1-knockdown OSCC cell lines. Our study demonstrated that SCRN1 is upregulated in OSCC. Further analyses demonstrated that SCRN1 promotes the proliferation, invasion and migration of OSCC cells via TGF-β/Smad3 signaling.

Plasma protein changes reflect colorectal cancer development and associated inflammation

Introduction

Colorectal cancer (CRC) is the third most common malignancy and the second leading cause of death worldwide. Efficient non-invasive blood-based biomarkers for CRC early detection and prognosis are urgently needed.

Methods

To identify novel potential plasma biomarkers, we applied a proximity extension assay (PEA), an antibody-based proteomics strategy to quantify the abundance of plasma proteins in CRC development and cancer-associated inflammation from few μL of plasma sample.

Results

Among the 690 quantified proteins, levels of 202 plasma proteins were significantly changed in CRC patients compared to age-and-sex-matched healthy subjects. We identified novel protein changes involved in Th17 activity, oncogenic pathways, and cancer-related inflammation with potential implications in the CRC diagnosis. Moreover, the interferon γ (IFNG), interleukin (IL) 32, and IL17C were identified as associated with the early stages of CRC, whereas lysophosphatidic acid phosphatase type 6 (ACP6), Fms-related tyrosine kinase 4 (FLT4), and MANSC domain-containing protein 1 (MANSC1) were correlated with the late-stages of CRC.

Discussion

Further study to characterize the newly identified plasma protein changes from larger cohorts will facilitate the identification of potential novel diagnostic, prognostic biomarkers for CRC.

Upregulation of MiR-1274a is Correlated with Survival Outcomes and Promotes Cell Proliferation, Migration, and Invasion of Colon Cancer

Purpose

Colon cancer has become one of the primary causes of cancer-related mortality in recent years. MicroRNAs (miRNAs) play important roles in the regulation of target genes expression. Some of these molecules are aberrantly expressed in colon cancer. The aim of this study was to investigate the potential role of miR-1274a in colon cancer.

Patients and Methods

The expression levels of miR-1274a in colon cancer tissues and cell lines were detected using RT-qPCR. The association between miR-1274a expression and clinical features was analyzed by the χ² test. Then the Kaplan–Meier method and multivariate Cox regression analysis were used to explore the clinical prognostic significance of miR-1274a in colon cancer. Finally, the effects of miR-1274a on cell growth, migration, and invasion were investigated with the CCK-8 assay, colony formation assay, transwell migration, and invasion assays, respectively.

Results

The expression of miR-1274a was increased in colon cancer tissues and cell lines. The miR-1274a expression was associated with lymph node metastasis, vascular invasion, and TNM stage. Patients with high miR-1274a expression had a poor overall survival time compared with those with low miR-1274a expression. Upregulated miR-1274a promoted cell proliferation, migration, and invasion of colon cancer cells, while inhibition of miR-1274a suppressed these cellular activities by targeting FOXO4.

Conclusion

Our study suggested that miR-1274a might function as an oncogene in human colon cancer and be a potential prognostic biomarker and therapeutic target for the treatment of colon cancer.

Secernin-1 is a novel phosphorylated tau binding protein that accumulates in Alzheimer's disease and not in other tauopathies

We recently identified Secernin-1 (SCRN1) as a novel amyloid plaque associated protein using localized proteomics. Immunohistochemistry studies confirmed that SCRN1 was present in plaque-associated dystrophic neurites and also revealed distinct and abundant co-localization with neurofibrillary tangles (NFTs). Little is known about the physiological function of SCRN1 and its role in Alzheimer's disease (AD) and other neurodegenerative diseases has not been studied. Therefore, we performed a comprehensive study of SCRN1 distribution in neurodegenerative diseases. Immunohistochemistry was used to map SCRN1 accumulation throughout the progression of AD in a cohort of 58 patients with a range of NFT pathology (Abundant NFT, n = 21; Moderate NFT, n = 22; Low/No NFT, n = 15), who were clinically diagnosed as having AD, mild cognitive impairment or normal cognition. SCRN1 accumulation was also examined in two cases with both Frontotemporal Lobar Degeneration (FTLD)-Tau and AD-related neuropathology, cases of Down Syndrome (DS) with AD (n = 5), one case of hereditary cerebral hemorrhage with amyloidosis - Dutch type (HCHWA-D) and other non-AD tauopathies including: primary age-related tauopathy (PART, [n = 5]), Corticobasal Degeneration (CBD, [n = 5]), Progressive Supranuclear Palsy (PSP, [n = 5]) and Pick's disease (PiD, [n = 4]). Immunohistochemistry showed that SCRN1 was a neuronal protein that abundantly accumulated in NFTs and plaque-associated dystrophic neurites throughout the progression of AD. Quantification of SCRN1 immunohistochemistry confirmed that SCRN1 preferentially accumulated in NFTs in comparison to surrounding non-tangle containing neurons at both early and late stages of AD. Similar results were observed in DS with AD and PART. However, SCRN1 did not co-localize with phosphorylated tau inclusions in CBD, PSP or PiD. Co-immunoprecipitation revealed that SCRN1 interacted with phosphorylated tau in human AD brain tissue. Together, these results suggest that SCRN1 is uniquely associated with tau pathology in AD, DS and PART. As such, SCRN1 has potential as a novel therapeutic target and could serve as a useful biomarker to distinguish AD from other tauopathies.

VAP-SCRN1 interaction regulates dynamic endoplasmic reticulum remodeling and presynaptic function

In neurons, the continuous and dynamic endoplasmic reticulum (ER) network extends throughout the axon, and its dysfunction causes various axonopathies. However, it remains largely unknown how ER integrity and remodeling modulate presynaptic function in mammalian neurons. Here, we demonstrated that ER membrane receptors VAPA and VAPB are involved in modulating the synaptic vesicle (SV) cycle. VAP interacts with secernin-1 (SCRN1) at the ER membrane via a single FFAT-like motif. Similar to VAP, loss of SCRN1 or SCRN1-VAP interactions resulted in impaired SV cycling. Consistently, SCRN1 or VAP depletion was accompanied by decreased action potential-evoked Ca2+ responses. Additionally, we found that VAP-SCRN1 interactions play an important role in maintaining ER continuity and dynamics, as well as presynaptic Ca2+ homeostasis. Based on these findings, we propose a model where the ER-localized VAP-SCRN1 interactions provide a novel control mechanism to tune ER remodeling and thereby modulate Ca2+ dynamics and SV cycling at presynaptic sites. These data provide new insights into the molecular mechanisms controlling ER structure and dynamics, and highlight the relevance of ER function for SV cycling.

Potential value of serum Progranulin as a biomarker for the presence and severity of micro vascular complications among Egyptian patients with type 2 diabetes mellitus

Objective

The increasing prevalence of type 2 diabetes mellitus (T2DM) calls for evolving a concomitant screening strategies for early disease detection and prediction of the complications. Progranulin (PRGN) was recently introduced as a biomarker of inflammation in T2DM. However, little data have been published as regarding progranulin in relation to diabetic micro angiopathy among Egyptian patients with T2DM. The aim of this study was therefore to investigate and evaluate serum progranulin as a biomarker for the presence and severity of micro vascular complications among Egyptian patients with T2DM.

Methods

A total of 90 age and sex matched participants were included in this cross sectional study. They were divided into group 1 included 30 non diabetic healthy controls and group 2 included 60 patients with type 2 diabetes mellitus. Furthermore, diabetic patients were categorized into two subgroups depending on the presence or absence of microvascular complications. Evaluation for diabetic nephropathy, neuropathy and retinopathy were determined. Furthermore, laboratory investigations were performed and serum progranulin levels were measured by a quantitative sandwich enzyme linked immune sorbent assay.

Results

The mean serum PRGN levels were significantly elevated in type 2 diabetic patients (20.90 ± 6.38 ng/ml) compared to control group (9.20 ± 1.41 ng/ml) (p < 0.001). Moreover,the serum PRGN levels were increased parallel to the severity of diabetic nephropathy (DN) and diabetic retinopathy (DR) with significantly highest detectable values were in macro albuminuric group of diabetic nephropathy as well as proliferative diabetic retinopathy (PDR) groups (P < 0.001). Besides, it worth mentioning that, the level of Serum progranulin started to increase significantly in stage 2 DN in spite of normal level of albuminuria. There were highly significant positive correlation between serum PRGN and disease duration, body mass index (BMI),fasting blood sugar (FBS), HbA1c, Total cholesterol (TC),triglyceride (TG), serum creatinine, ACR (r = 0.918, 0.623, 0.430, 0.539,0.910,0.842,0.759, 0.903, resp., P < 0.001) and a significant positive correlation with low density lipoprotein (LDL) (r = 0.344),but there was a highly significant negative correlation between serum PRGN and eGFR (r = -0.866, P < 0.001) in the studied diabetic patients.

Conclusion

Progranulin might be considered as a biomarker for diabetic micro angiopathy and its severity. In addition, there is a group of diabetic patients with decreased eGFR but without albuminuria in which serum PRGN level was indicated to be used as an early biomarker of diabetic nephropathy.

Proteomics Analysis Reveals the Implications of Cytoskeleton and Mitochondria in the Response of the Rat Brain to Starvation

Long-term starvation provokes a metabolic response in the brain to adapt to the lack of nutrient intake and to maintain the physiology of this organ. Here, we study the changes in the global proteomic profile of the rat brain after a seven-day period of food deprivation, to further our understanding of the biochemical and cellular mechanisms underlying the situations without food. We have used two-dimensional electrophoresis followed by mass spectrometry (2D-MS) in order to identify proteins differentially expressed during prolonged food deprivation. After the comparison of the protein profiles, 22 brain proteins were found with altered expression. Analysis by peptide mass fingerprinting and MS/MS (matrix-assisted laser desorption-ionization-time of flight mass spectrometer, MALDI-TOF/TOF) enabled the identification of 14 proteins differentially expressed that were divided into 3 categories: (1) energy catabolism and mitochondrial proteins; (2) chaperone proteins; and (3) cytoskeleton, exocytosis, and calcium. Changes in the expression of six proteins, identified by the 2D-MS proteomics procedure, were corroborated by a nanoliquid chromatography-mass spectrometry proteomics procedure (nLC-MS). Our results show that long-term starvation compromises essential functions of the brain related with energetic metabolism, synapsis, and the transmission of nervous impulse.

Long noncoding RNA BC200 regulates cell growth and invasion in colon cancer

Colon cancer is the third most commonly diagnosed and deadly cancer worldwide. Efforts have been made to characterize its pathological mechanisms and to explore new therapeutic targets of this disease. Aberrant expression of long noncoding RNAs (lncRNAs) has been associated with the pathogenesis of colon cancer. In the current study, we aimed to define the biological mechanism of the lncRNA BC200 in colon cancer. Here, we found that expression of BC200 was up-regulated in colon cancer tissues as compared with adjacent non-cancerous tissues. The BC200 level was positively correlated with advanced TNM stage. The Kaplan-Meier method indicated that the cumulative survival rate was significantly lower in patients with high BC200 expression than in those with low BC200 expression. Interestingly, we found that knockdown of BC200 inhibited proliferation of HCT-116 and HT29 colon cancer cell lines and reduce the expression of cell proliferation markers, such as Ki-67 and PCNA. In addition, silencing of BC200 could induce obvious G0/G1 arrest and cause apoptosis in HCT-116 and HT29 cells and reduced the expression of cyclin D1, cyclin E, and c-Myc through inhibiting the expression of β-catenin. Importantly, we found that knockdown of BC200 reduced invasion of HCT-116 and HT29 cells and epithelial-mesenchymal transition (EMT) by reducing the expression of MMP-2 and MMP-9. Mechanistically, silencing of BC200 significantly reduced the phosphorylation of STAT3. Overall, the findings presented here suggest that lncRNA BC200 may serve as a novel oncogene and a new therapeutic target for colon cancer.

Integrated genomic approaches identify upregulation of SCRN1 as a novel mechanism associated with acquired resistance to erlotinib in PC9 cells harboring oncogenic EGFR mutation

Therapies targeting the tyrosine kinase activity of Epidermal Growth Factor Receptor (EGFR) have been proven to be effective in treating a subset of non-small cell lung cancer (NSCLC) patients harboring activating EGFR mutations. Inevitably these patients develop resistance to the EGFR-targeted tyrosine kinase inhibitors (TKIs). Here, we performed integrated genomic analyses using an in vitro system to uncover alternative genomic mechanisms responsible for acquired resistance to EGFR-TKIs. Specifically, we identified 80 genes whose expression is significantly increased in the erlotinib-resistant clones. RNAi-based systematic synthetic lethal screening of these candidate genes revealed that suppression of one upregulated transcript, SCRN1, a secernin family member, restores sensitivity to erlotinib by enhancing inhibition of PI3K/AKT signaling pathway. Furthermore, immunohistochemical analysis revealed increased levels of SCRN1 in 5 of 11 lung tumor specimens from EGFR-TKIs resistant patients. Taken together, we propose that upregulation of SCRN1 is an additional mechanism associated with acquired resistance to EGFR-TKIs and that its suppression serves as a novel therapeutic strategy to overcome drug resistance in these patients.

Metastatic biomarkers in synovial sarcoma

Synovial sarcoma (SS) is an aggressive soft tissue sarcoma (STS) that typically occurs in the extremities near a joint. Metastatic disease is common and usually occurs in the lungs and lymph nodes. Surgical management is the mainstay of treatment with chemotherapy and radiation typically used as adjuvant treatment. Although chemotherapy has a positive impact on survival, the prognosis is poor if metastatic disease occurs. The biology of sarcoma invasion and metastasis remain poorly understood. Chromosomal translocation with fusion of the SYT and SSX genes has been described and is currently used as a diagnostic marker, although the full impact of the fusion is unknown. Multiple biomarkers have been found to be associated with SS and are currently under investigation regarding their pathways and mechanisms of action. Further research is needed in order to develop better diagnostic screening tools and understanding of tumor behavior. Development of targeted therapies that reduce metastatic events in SS, would dramatically improve patient prognosis.