Harnessing low-density lipoprotein receptor protein 6 (LRP6) genetic variation and Wnt signaling for innovative diagnostics in complex diseases

Improvement of spatial memory dysfunction in type 2 diabetic mice through a low-carbohydrate and high-protein diet: potential role of LRP6/Wnt3a signaling in the hippocampus

Hippocampal dysfunction associated with type 2 diabetes mellitus (T2DM), including deficits in spatial learning and memory, represent a significant challenge to overall health. Dietary interventions are considered effective therapeutic approaches for managing metabolic parameters in T2DM, with a low-carbohydrate and high-protein (LC-HP) diet being a representative example. However, the impact of an LC-HP diet on hippocampal dysfunction in T2DM remains unclear. In this study, we examined the potential role of an LC-HP diet to alleviate spatial memory impairments. C57BL/6J and ob/ob mice were assigned to either an LC-HP diet group (25.1% carbohydrate, 57.2% protein, and 17.7% fat as percentages of calories) or a control diet group (58.9% carbohydrate, 24.0% protein, and 17.1% fat as percentages of calories). After four weeks of dietary intervention, all mice underwent the Morris water maze test, followed by hippocampal mRNA expression analysis. The findings demonstrated that the LC-HP diet improved spatial memory performance in ob/ob mice. This dietary regimen mitigated the downregulation of hippocampal mRNA levels for low-density lipoprotein receptor-related protein 6 (Lrp6), IGF-1 receptor (Igf1r), and Wnt3a observed in ob/ob mice. These results suggest that modulating biochemical molecules may play a role in ameliorating memory deficits associated with T2DM through LC-HP dietary interventions, highlighting potential targets for developing nutritional strategies to address hippocampal dysfunction caused by T2DM.

Proximogram-A multi-omics network-based framework to capture tissue heterogeneity integrating single-cell omics and spatial profiling

The increasing availability of patient-derived multimodal biological data for various diseases has opened up avenues for finding the optimal methods for jointly leveraging the information extracted in a customizable and scalable manner. Here, we propose the Proximogram, a graph-based representation that provides a joint construct for embedding independently obtained omics and spatial data. To evaluate the representation, we generated proximograms from 2 distinct biological sources, namely, multiplexed immunofluorescence images and single-cell RNA-seq data obtained from patients across two pancreatic diseases that include normal and chronic Pancreatitis (CP) and pancreatic ductal adenocarcinoma (PDAC). The generated proximograms were used as inputs to 2 distinct graph deep-learning models. The improved classification results over simpler spatial-data-based input graphs point to the increased discriminatory power obtained by integrating structural information from single-cell ligand-receptor signaling data and the spatial architecture of cells in each disease class, which can help point to markers of high diagnostic significance.

Exosomal circFBLIM1 Promotes Hepatocellular Carcinoma Progression and Glycolysis by Regulating the miR-338/LRP6 Axis

Background: Hepatocellular carcinoma (HCC) is the most common form of liver cancer. Circular RNAs (circRNAs) play a vital role in cancer development and progression. This study investigated the role and potential mechanism of circRNA filamin binding LIM protein 1 (circFBLIM1) in HCC. Methods: Exosomes were identified by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and Western blot assay. The levels of circFBLIM1, miR-338, and low-density lipoprotein receptor-related protein 6 (LRP6) were measured by quantitative real-time polymerase chain reaction or Western blot. Glycolysis was analyzed by detecting glucose consumption, lactate production, ATP level, extracellular acidification rate (ECAR), and oxygen consumption rate (OCR). Cell viability was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Cell apoptosis was detected by flow cytometry. Xenograft assay was performed to analyze tumor growth in vivo. The interaction among circFBLIM1, miR-338, and LRP6 was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. This study was approved by the Institutional Review Board of the First Affiliated Hospital of Guizhou University of Traditional Chinese Medicine. Results: CircFBLIM1 was highly expressed in HCC serum exosomes and HCC cells. Inhibition of circFBLIM1 confined HCC glycolysis and progression. CircFBLIM1 knockdown blocked tumorigenesis in vivo. CircFBLIM1 was a sponge of miR-338 and promoted HCC progression and glycolysis by regulating miR-338. Moreover, miR-338 suppressed HCC progression and glycolysis via targeting LRP6. Mechanistically, circFBLIM1 functioned as an miR-338 sponge to upregulate LRP6. Conclusion: CircFBLIM1 facilitated HCC progression and glycolysis via modulating the miR-338/LRP6 axis, which may provide promising therapeutic targets for HCC.

LRP6 Bidirectionally Regulates Insulin Sensitivity through Insulin Receptor and S6K Signaling in Rats with CG-IUGR

OBJECTIVE

Intrauterine growth restriction followed by postnatal catch-up growth (CG-IUGR) increases the risk of insulin resistance-related diseases. Low-density lipoprotein receptor-related protein 6 (LRP6) plays a substantial role in glucose metabolism. However, whether LRP6 is involved in the insulin resistance of CG-IUGR is unclear. This study aimed to explore the role of LRP6 in insulin signaling in response to CG-IUGR.

METHODS

The CG-IUGR rat model was established via a maternal gestational nutritional restriction followed by postnatal litter size reduction. The mRNA and protein expression of the components in the insulin pathway, LRP6/β-catenin and mammalian target of rapamycin (mTOR)/S6 kinase (S6K) signaling, was determined. Liver tissues were immunostained for the expression of LRP6 and β-catenin. LRP6 was overexpressed or silenced in primary hepatocytes to explore its role in insulin signaling.

RESULTS

Compared with the control rats, CG-IUGR rats showed higher homeostasis model assessment for insulin resistance (HOMA-IR) index and fasting insulin level, decreased insulin signaling, reduced mTOR/S6K/ insulin receptor substrate-1 (IRS-1) serine307 activity, and decreased LRP6/β-catenin in the liver tissue. The knockdown of LRP6 in hepatocytes from appropriate-for-gestational-age (AGA) rats led to reductions in insulin receptor (IR) signaling and mTOR/S6K/IRS-1 serine307 activity. In contrast, LRP6 overexpression in hepatocytes of CG-IUGR rats resulted in elevated IR signaling and mTOR/S6K/IRS-1 serine307 activity.

CONCLUSION

LRP6 regulated the insulin signaling in the CG-IUGR rats via two distinct pathways, IR and mTOR-S6K signaling. LRP6 may be a potential therapeutic target for insulin resistance in CG-IUGR individuals.

The functional role of circular RNAs in the pathogenesis of retinoblastoma: a new potential biomarker and therapeutic target?

Retinoblastoma (RB) is a common cancer in infants and children. It is a curable disease; however, a delayed diagnosis or treatment makes the treatment difficult. Genetic mutations have a central role in the pathogenesis of RB. Genetic materials such as RNAs (coding and non-coding RNAs) are also involved in the progression of the tumor. Circular RNA (circRNA) is the most recently identified RNA and is involved in regulating gene expression mainly through "microRNA sponges". The dysregulation of circRNAs has been observed in several diseases and tumors. Also, various studies have shown that circRNAs expression is changed in RB tissues. Due to their role in the pathogenesis of the disease, circRNAs might be helpful as a diagnostic or prognostic biomarker in patients with RB. In addition, circRNAs could be a suitable therapeutic target to treat RB in a targeted therapy approach.

LRP6 Is a Functional Receptor for Attenuated Canine Distemper Virus

Wild-type canine distemper virus (CDV) is an important pathogen of dogs as well as wildlife that can infect immune and epithelial cells through two known receptors: the signaling lymphocytic activation molecule (SLAM) and nectin-4, respectively. Conversely, the ferret and egg-adapted CDV-Onderstepoort strain (CDV-OP) is employed as an effective vaccine for dogs. CDV-OP also exhibits promising oncolytic properties, such as its abilities to infect and kill multiple cancer cells in vitro. Interestingly, several cancer cells do not express SLAM or nectin-4, suggesting the presence of a yet unknown entry factor for CDV-OP. By conducting a genome-wide CRISPR/Cas9 knockout (KO) screen in CDV-OP-susceptible canine mammary carcinoma P114 cells, which neither express SLAM nor nectin-4, we identified low-density lipoprotein receptor-related protein 6 (LRP6) as a host factor that promotes CDV-OP infectivity. Whereas the genetic ablation of LRP6 rendered cells resistant to infection, ectopic expression in resistant LRP6KO cells restored susceptibility. Furthermore, multiple functional studies revealed that (i) the overexpression of LRP6 leads to increased cell-cell fusion, (ii) a soluble construct of the viral receptor-binding protein (solHOP) interacts with a soluble form of LRP6 (solLRP6), (iii) an H-OP point mutant that prevents interaction with solLRP6 abrogates cell entry in multiple cell lines once transferred into recombinant viral particles, and (iv) vesicular stomatitis virus (VSV) pseudotyped with CDV-OP envelope glycoproteins loses its infectivity in LRP6KO cells. Collectively, our study identified LRP6 as the long sought-after cell entry receptor of CDV-OP in multiple cell lines, which set the molecular bases to refine our understanding of viral-cell adaptation and to further investigate its oncolytic properties. IMPORTANCE Oncolytic viruses (OV) have gathered increasing interest in recent years as an alternative option to treat cancers. The Onderstepoort strain of canine distemper virus (CDV-OP), an enveloped RNA virus belonging to the genus Morbillivirus, is employed as a safe and efficient vaccine for dogs against distemper disease. Importantly, although CDV-OP can infect and kill multiple cancer cell lines, the basic mechanisms of entry remain to be elucidated, as most of those transformed cells do not express natural receptors (i.e., SLAM and nectin-4). In this study, using a genome-wide CRISPR/Cas9 knockout screen, we describe the discovery of LRP6 as a novel functional entry receptor for CDV-OP in various cancer cell lines and thereby uncover a basic mechanism of cell culture adaptation. Since LRP6 is upregulated in various cancer types, our data provide important insights in order to further investigate the oncolytic properties of CDV-OP.

Receptors that bind to PEDF and their therapeutic roles in retinal diseases

Retinal neovascular, neurodegenerative, and inflammatory diseases represented by diabetic retinopathy are the main types of blinding eye disorders that continually cause the increased burden worldwide. Pigment epithelium-derived factor (PEDF) is an endogenous factor with multiple effects including neurotrophic activity, anti-angiogenesis, anti-tumorigenesis, and anti-inflammatory activity. PEDF activity depends on the interaction with the proteins on the cell surface. At present, seven independent receptors, including adipose triglyceride lipase, laminin receptor, lipoprotein receptor-related protein, plexin domain-containing 1, plexin domain-containing 2, F1-ATP synthase, and vascular endothelial growth factor receptor 2, have been demonstrated and confirmed to be high affinity receptors for PEDF. Understanding the interactions between PEDF and PEDF receptors, their roles in normal cellular metabolism and the response the initiate in disease will be accommodating for elucidating the ways in which inflammation, angiogenesis, and neurodegeneration exacerbate disease pathology. In this review, we firstly introduce PEDF receptors comprehensively, focusing particularly on their expression pattern, ligands, related diseases, and signal transduction pathways, respectively. We also discuss the interactive ways of PEDF and receptors to expand the prospective understanding of PEDF receptors in the diagnosis and treatment of retinal diseases.

IUGR with catch-up growth programs impaired insulin sensitivity through LRP6/IRS-1 in male rats

Intrauterine growth restriction combined with postnatal accelerated growth (CG-IUGR) could lead to long-term detrimental metabolic outcomes characterized by insulin resistance. As an indispensable co-receptor of Wnt signaling, LRP6 plays a critical role in the susceptibility of metabolic disorders. However, whether LRP6 is involved in the metabolic programing is still unknown. We hypothesized that CG-IUGR programed impaired insulin sensitivity through the impaired LRP6-mediated Wnt signaling in skeletal muscle. A CG-IUGR rat model was employed. The transcriptional and translational alterations of the components of the Wnt and the insulin signaling in the skeletal muscle of the male CG-IUGR rats were determined. The role of LRP6 on the insulin signaling was evaluated by shRNA knockdown or Wnt3a stimulation of LRP6. Compared with controls, the male CG-IUGR rats showed an insulin-resistant phenotype, with impaired insulin signaling and decreased expression of LRP6/β-catenin in skeletal muscle. LRP6 knockdown led to reduced expression of the IR-β/IRS-1 in C2C12 cell line, while Wnt3a-mediated LRP6 expression increased the expression of IRS-1 and IGF-1R but not IR-β in the primary muscle cells of male CG-IUGR rats. The impaired LRP6/β-catenin/IGF-1R/IRS-1 signaling is probably one of the critical mechanisms underlying the programed impaired insulin sensitivity in male CG-IUGR.

LRP6 Receptor Plays Essential Functions in Development and Human Diseases

LRP6 is a member of the low-density lipoprotein receptor superfamily of cell-surface receptors. It is required for the activation of the Wnt/β-catenin signalling pathway. LRP6 is detected in different tissue types and is involved in numerous biological activities such as cell proliferation, specification, metastatic cancer, and embryonic development. LRP6 is essential for the proper development of different organs in vertebrates, such as Xenopus laevis, chickens, and mice. In human, LRP6 overexpression and mutations have been reported in multiple complex diseases including hypertension, atherosclerosis, and cancers. Clinical studies have shown that LRP6 is involved in various kinds of cancer, such as bladder and breast cancer. Therefore, in this review, we focus on the structure of LRP6 and its interactions with Wnt inhibitors (DKK1, SOST). We also discuss the expression of LRP6 in different model systems, with emphasis on its function in development and human diseases.

Changes of LRP6/β-catenin pathway in adipose tissue of rats with intrauterine growth restriction with catch-up growth

To investigate the expression of low-density lipoprotein receptor-related protein 6 (LRP6)/β-catenin pathway related proteins in adipose tissue of rats with intrauterine growth restriction with catch-up growth SD rats were randomly divided into nutrition-restriction rats and normal feed rats during pregnancy. CG-IUGR model was established by reducing the number of offspring in the nutrition-restriction rats (CG-IUGR group); while the rats in the control group were offspring of the normal feed pregnant rats. In order to exclude the interference of gender, male offspring mice were selected in both the CG-IUGR group and the control group in the following studies. The CG-IUGR group and the control group were subjected to glucose tolerance test at 12 weeks of age, and the perirenal adipose tissue samples were taken to observe the adipose structure by HE staining. Expression of LRP6, β-catenin and insulin receptor substrate 1 (IRS-1) in adipocytes were examined by confocal microscopy. Protein expression of LRP6, β-catenin and IRS-1 were measured by Western blotting. Blood glucose level and the area under the cure of CG-IUGR group were significantly higher than that of control group (both <0.05). Adipocyte size in the CG-IUGR group was significantly larger than that of control group, and the expression of LRP6, β-catenin and IRS-1 protein in adipose tissue of the CG-IUGR group was significantly lower than that of control group (all <0.05). : The expression of LRP6/β-catenin pathway related proteins is reduced in the adipose tissue in CG-IUGR rats, probably contributing to the insulin resistance in these rats.

Identification of Novel Variants in Cleft Palate-Associated Genes in Brazilian Patients With Non-syndromic Cleft Palate Only

The identification of genetic risk factors for non-syndromic oral clefts is of great importance for better understanding the biological processes related to this heterogeneous and complex group of diseases. Herein we applied whole-exome sequencing to identify potential variants related to non-syndromic cleft palate only (NSCPO) in the multiethnic Brazilian population. Thirty NSCPO samples and 30 sex- and genetic ancestry-matched healthy controls were pooled (3 pools with 10 samples for each group) and subjected to whole-exome sequencing. After filtering, the functional affects, individually and through interactions, of the selected variants and genes were assessed by bioinformatic analyses. As a group, 399 variants in 216 genes related to palatogenesis/cleft palate, corresponding to 6.43%, were exclusively identified in the NSCPO pools. Among those genes are 99 associated with syndromes displaying cleft palate in their clinical spectrum and 92 previously related to cleft lip palate. The most significantly biological processes and pathways overrepresented in the NSCPO-identified genes were associated with the folic acid metabolism, highlighting the interaction between LDL receptor-related protein 6 (LRP6) and 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR) that interconnect two large networks. This study yields novel data on characterization of specific variants and complex processes and pathways related to NSCPO, including many variants in genes of the folate/homocysteine pathway, and confirms that variants in genes related to syndromic cleft palate and cleft lip-palate may cause NSCPO.

Repositioning of antidiabetic drugs for Alzheimer's disease: possibility of Wnt signaling modulation by targeting LRP6 an in silico based study

Alzheimer disease (AD) is the most common, irreversible and progressive form of dementia for which the exact pathology and cause are still not clear. At present, we are only confined to symptomatic treatment, and the lack of disease-modifying therapeutics is worrisome. Alteration of Wnt signaling has been linked to metabolic diseases as well as AD. The crosstalk between Canonical Wnt signaling and insulin signaling pathway has been widely studied and accepted from several clinical and preclinical studies that have proven the beneficial effect of antidiabetic medications in the case of memory and cognition loss. This structure-based in silico study was focused on exploring the link between the currently available FDA approved antidiabetic drugs and the Wnt signaling pathway. The library of antidiabetics was obtained from drug bank and was screened for their binding affinity with protein (PDB ID: 3S2K) LRP6, a coreceptor of the Wnt signaling pathway using GLIDE module of Schrodinger. The top molecules, with higher docking score, binding energy and stable interactions, were subjected to energy-based calculation using MMGBSA, followed by a molecular dynamics-based simulation study. Drugs of class α-glucosidase inhibitors and peroxisome proliferator-activated receptors (PPARs) agonists were found to have a strong affinity towards LRP6 proteins, highlighting the possibility of the modulation of Wnt signaling by antidiabetics as one of the possible mechanisms for use in AD. However, further experimental based in vitro and in vivo studies are warranted for verification and support.Communicated by Ramaswamy H. Sarma.

Hsa_circ_0099198 facilitates the progression of retinoblastoma by regulating miR-1287/LRP6 axis

Retinoblastoma (RB) is an intraocular malignancy that occurs in children. Circular RNAs (circRNAs) have been confirmed to play an essential role in tumorigenesis and development. This study aimed to ascertain the role and potential mechanism of hsa_circ_0099198 in RB. The levels of circ_0099198, microRNA-1287 (miR-1287) and low-density lipoprotein receptor-related protein 6 (LRP6) were determined by real-time quantitative polymerase chain reaction and Western blot. Cell proliferation was assessed by colony formation assay. Cell cycle arrest and apoptosis were evaluated by flow cytometry. Cell migration and invasion were tested using transwell assay. The activity of caspase-3/caspase-9 was examined with commercial kits. The interaction among circ_0099198, miR-1287 and LRP6 were verified by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay or RNA pull-down assay. Xenograft experiment was used to assess tumor growth in vivo. circ_0099198 and LRP6 levels were increased, while miR-1287 level was reduced in RB cells. circ_0099198 silencing suppressed proliferation and metastasis and expedited cell cycle arrest and apoptosis in Y79 and So-RB50 cells. In addition, depletion of circ_0099198 inhibited RB cell progression via regulating miR-1287/LRP6 axis. Moreover, knockdown of circ_0099198 blocked the growth of xenograft tumors. circ_0099198 contributed to RB progression by sponging miR-1287 and up-regulating LRP6, which provided novel biomarkers for RB therapy.

Alzheimer's Disease: An Overview of Major Hypotheses and Therapeutic Options in Nanotechnology

Alzheimer's disease (AD), a progressively fatal neurodegenerative disorder, is the most prominent form of dementia found today. Patients suffering from Alzheimer's begin to show the signs and symptoms, like decline in memory and cognition, long after the cellular damage has been initiated in their brain. There are several hypothesis for the neurodegeneration process; however, the lack of availability of in vivo models makes the recapitulation of AD in humans impossible. Moreover, the drugs currently available in the market serve to alleviate the symptoms and there is no cure for the disease. There have been two major hurdles in the process of finding the same-the inefficiency in cracking the complexity of the disease pathogenesis and the inefficiency in delivery of drugs targeted for AD. This review discusses the different drugs that have been designed over the recent years and the drug delivery options in the field of nanotechnology that have been found most feasible in surpassing the blood-brain barrier (BBB) and reaching the brain.

In-silico identification of new inhibitors for Low-density lipoprotein receptor-related protein6 (LRP6)

Low-density lipoprotein receptor-related protein 6 (LRP6) is an important therapeutic target for diseases such as osteoporosis, Alzheimer, cancer, and neurodegenerative disease. Computational methods such as ligand-based and structure-based virtual screening have been introduced as an extremely efficient and accurate tool for finding new drug targets and candidates. In this study, we aimed to screen the National Cancer Institute (NCI) Diversity Set II and parts of the ZINC database by virtual screening to identify potential and safe compounds that can inhibit the LRP6 protein. By utilizing various screening methods such as rigid and flexible molecular docking and Lipinski's rule of five, we identified 10 potential compounds. Then, their validity was further tested by molecular dynamics simulation and MMPBSA binding free energy calculations. Eventually, it was concluded that ZINC03954520, ZINC01729523, ZINC03898665, ZINC13152226, ZINC26730911 and ZINC01069082 compounds can be potential drug compounds for inhibiting LRP6 protein. These compounds in complex with β-propeller domains of LRP6 showed that they are capable of altering the backbone of these domains and interfere with their structural dynamics which may lead to the inhibition of the signal transmission. Communicated by Ramaswamy H. Sarma.

Macrocyclic peptides that inhibit Wnt signalling via interaction with Wnt3a

Here we report de novo macrocyclic peptide binders to Wnt3a, a member of the Wnt protein family. By means of the Random non-standard Peptides Integrated Discovery (RaPID) system, we have performed in vitro selection against the complex of mouse Wnt3a (mWnt3a) with human afamin (hAFM) to discover macrocyclic peptides that bind mWnt3a with K _D values as tight as 110 nM. One of these peptides, WAp-D04 (Wnt-AFM-peptide-D04), was able to inhibit the receptor-mediated signaling process, which was demonstrated in a Wnt3a-dependent reporter cell-line. Based on this initial hit, we applied a block-mutagenesis scanning display to identify a mutant inhibitor, WAp-D04-W10P, with 5-fold greater potency in a reporter assay. This work represents the first instance of molecules capable of inhibiting Wnt signaling through direct interaction with a Wnt protein, a molecular class for which targeting has been challenging due its highly hydrophobic nature.

The involvement of the canonical Wnt-signaling receptor LRP5 and LRP6 gene variants with ADHD and sexual dimorphism: Association study and meta-analysis

Wnt-signaling is one of the most abundant pathways involved in processes such as cell-proliferation, -polarity, and -differentiation. Altered Wnt-signaling has been linked with several neurodevelopmental disorders including attention-deficit/hyperactivity disorder (ADHD) as well as with cognitive functions, learning and memory. Particularly, lipoprotein receptor-related protein 5 (LRP5) or LRP6 coreceptors, responsible in the activation of the canonical Wnt-pathway, were associated with cognitive alterations in psychiatric disorders. Following the hypothesis of Wnt involvement in ADHD, we investigated the association of genetic variations in LRP5 and LRP6 genes with three independent child and adolescent ADHD (cADHD) samples (total 2,917 participants), followed by a meta-analysis including previously published data. As ADHD is more prevalent in males, we stratified the analysis according to sex and compared the results with the recent ADHD Psychiatric Genomic Consortium (PGC) GWAS. Meta-analyzing our data including previously published cADHD studies, association of LRP5 intronic rs4988319 and rs3736228 (Ala1330Val) with cADHD was observed among girls (OR = 1.80 with 95% CI = 1.07-3.02, p = .0259; and OR = 2.08 with 95% CI = 1.01-4.46, p = .0026, respectively), whereas in boys association between LRP6 rs2302685 (Val1062Ile) and cADHD was present (OR = 1.66, CI = 1.20-2.31, p = .0024). In the PGC-ADHD dataset (using pooled data of cADHD and adults) tendency of associations were observed only among females with OR = 1.09 (1.02-1.17) for LRP5 rs3736228 and OR = 1.18 (1.09-1.25) for LRP6 rs2302685. Together, our findings suggest a potential sex-specific link of cADHD with LRP5 and LRP6 gene variants, which could contribute to the differences in brain maturation alterations in ADHD affected boys and girls, and suggest possible therapy targets.

Potential Fluid Biomarkers for the Diagnosis of Mild Cognitive Impairment

Mild cognitive impairment (MCI) is characterized by a level of cognitive impairment that is lower than normal for a person’s age, but a higher function than that that observed in a demented person. MCI represents a transitional state between normal aging and dementia disorders, especially Alzheimer’s disease (AD). Much effort has been made towards determining the prognosis of a person with MCI who will convert to AD. It is now clear that cerebrospinal fluid (CSF) levels of Aβ40, Aβ42, total tau and phosphorylated tau are useful for predicting the risk of progression from MCI to AD. This review highlights the advantages of the current blood-based biomarkers in MCI, and discusses some of these challenges, with an emphasis on recent studies to provide an overview of the current state of MCI.

Association between rs12742784 polymorphism and hip fracture, bone mineral density, and EPHB2 mRNA expression levels in elderly Chinese women

Objective: This study aimed to determine the association between rs12742784 polymorphism in the non-coding area and hip fracture, bone mineral density (BMD), and EPHB2 mRNA expression levels in elderly Chinese women.Methods: We investigated 250 Chinese women (mean age: 63.5 ± 8.3 years) including 123 hip fracture patients and 127 non-fracture controls. All participants underwent clinical examination to meet the inclusion criteria. Lumbar and hip BMD were detected by dual-energy X-ray absorptiometry. rs12742784 polymorphism was determined by restriction fragment length polymorphism and EPHB2 mRNA expression levels were measured by real-time polymerase chain reaction.Results: Distribution of rs12742784 genotypes agreed with Hardy-Weinberg equilibrium. The frequency of the CT + TT genotype was significantly associated with decreased risk of hip fracture (adjusted odds ratio = 0.57, p < 0.01) after adjusting for age and body mass index, and with increased BMD and EPHB2 mRNA expression levels. The T allele of the rs12742784 single nucleotide polymorphism (SNP) was a protective factor for hip fracture (adjusted odds ratio = 0.56, p < 0.01).Conclusion: rs12742784 polymorphism was associated with EPHB2 mRNA expression levels, BMD, and hip fracture in Chinese women. The T allele of the rs12742784 SNP was a protective factor for osteoporosis and hip fracture.

A panel of noncoding RNAs in non-small-cell lung cancer

Non-small-lung cancer (NSCLC) is the leading cause of cancer death. Early detection of NSCLC could pave the way for effective therapies. Analysis of molecular genetic biomarkers in biological fluids has been proposed as a useful tool for cancer diagnosis. Here, we aimed to develop a panel of noncoding RNAs (ncRNAs) in sputum for NSCLC early detection. Expression of 11 ncRNAs were analyzed by real-time polymerase chain reaction in sputum samples of 30 NSCLC patients and 30 sex- and age-matched cancer-free controls. Stability of endogenous microRNAs (miRNAs) in sputum was evaluated after 3 and 6 days at 4°C, 6 months, and 1 year at -80°C. Nine ncRNAs showed significant differences of their expression in sputum between NSCLC patients and controls. A logistic regression model with the best prediction was built based on miR-145, miR-126, and miR-7. The composite of the three miRNAs produced 90% sensitivity and specificity in distinguishing NSCLC patients from the controls. Results indicate that miRNAs could be useful biomarkers based on their stability under various storage conditions and maintain differential changes between cancer and control groups. Moreover, measurement of miRNAs in sputum could be a noninvasive approach for detection of lung cancer.

Whole exome sequencing identifies mutations in 10% of patients with familial non-syndromic cleft lip and/or palate in genes mutated in well-known syndromes

Background

Oral clefts, that is, clefts of the lip and/or cleft palate (CL/P), are the most common craniofacial birth defects with an approximate incidence of ~1/700. To date, physicians stratify patients with oral clefts into either syndromic CL/P (syCL/P) or non-syndromic CL/P (nsCL/P) depending on whether the CL/P is associated with another anomaly or not. In general, patients with syCL/P follow Mendelian inheritance, while those with nsCL/P have a complex aetiology and, as such, do not adhere to Mendelian inheritance. Genome-wide association studies have identified approximately 30 risk loci for nsCL/P, which could explain a small fraction of heritability.

Methods

To identify variants causing nsCL/P, we conducted whole exome sequencing on 84 individuals with nsCL/P, drawn from multiplex families (n=46).

Results

We identified rare damaging variants in four genes known to be mutated in syCL/P: TP63 (one family), TBX1 (one family), LRP6 (one family) and GRHL3 (two families), and clinical reassessment confirmed the isolated nature of their CL/P.

Conclusion

These data demonstrate that patients with CL/P without cardinal signs of a syndrome may still carry a mutation in a gene linked to syCL/P. Rare coding and non-coding variants in syCL/P genes could in part explain the controversial question of ‘missing heritability’ for nsCL/P. Therefore, gene panels designed for diagnostic testing of syCL/P should be used for patients with nsCL/P, especially when there is at least third-degree family history. This would allow a more precise management, follow-up and genetic counselling. Moreover, stratified cohorts would allow hunting for genetic modifiers.