Extracellular vesicles in non-small cell lung cancer stemness and clinical applications.

Non-small cell lung carcinoma (NSCLC) accounts for 85% of lung cancers, the leading cause of cancer associated deaths in the US and worldwide. Within NSCLC tumors, there is a subpopulation of cancer cells termed cancer stem cells (CSCs) which exhibit stem-like properties that drive NSCLC progression, metastasis, relapse, and therapeutic resistance. Extracellular vesicles (EVs) are membrane-bound nanoparticles secreted by cells that carry vital messages for short- and long-range intercellular communication. Numerous studies have implicated NSCLC CSC-derived EVs in the factors associated with NSCLC lethality. In this review, we have discussed mechanisms of EV-directed cross-talk between CSCs and cells of the tumor microenvironment that promote stemness, tumor progression and metastasis in NSCLC. The mechanistic studies discussed herein have provided insights for developing novel NSCLC diagnostic and prognostic biomarkers and strategies to therapeutically target the NSCLC CSC niche.

Rats' testicular toxicity induced by bisphenol A is lessened by crocin via an antiapoptotic mechanism and bumped P-glycoprotein expression.

Bisphenol A (BPA) engenders testicular toxicity via hydroxyl free radical genesis in rat striatum and depletion of the endogenous antioxidants in the epididymal sperms. The multi-drug resistance efflux carrier; P-glycoprotein (P-gp) expel the BPA from the testis and is responsible for the testicular protection through the deactivation of numerous xenobiotics. In our study, we investigated whether the BPA-induced testicular toxicity could be circumvented through administration of an antioxidant; crocin (Cr). Implication of P-gp expression was also investigated. Rats administered BPA (10 mg/kg b.w. orally for 14 days), dropped the body weight, testes/body weight ratio, total protein content, testosterone, follicle stimulating hormone, luteinizing hormone, and sperm motility & count, total antioxidant status, glutathione content and antioxidant enzymes (superoxide dismutase and catalase), concomitant with the elevation of the percentage abnormal sperm morphology, as well as testicular lipid peroxides and nitrite/nitrate levels. Histopathological examination showed spermatogenesis disorders after the BPA rats exposure. The immunohistochemical study showed up-regulation of the P-gp as evident by increasing immunoreactivity in interstitial cells, with positive localization in some spermatogonia cells. The BPA-treated rats showed positive immunoreactivity against caspase-3. The co-intake of Cr (200 mg/kg b.w./day, i.p. 14 days) along with the BPA, significantly ameliorated all the mentioned parameters, boosted histopathological image, fell the caspase-3 up-regulation, and perched the P-gp expression. We showed that, Cr promotes P-gp as an approach to nurture the testicles against the BPA toxicity. In conclusion; Cr lessens the oxidative stress conditions to safeguard rats from the BPA-induced testicular toxicity and sex hormones abnormalities, reducing apoptosis and up-regulating P-gp.

The impact of metformin on weight and metabolic parameters in patients with obesity: A systematic review and meta-analysis of randomized controlled trials.

There are conflicting data on the weight-reducing potential of metformin (MTF) in nondiabetic patients with obesity. The purpose of this systematic review and meta-analysis was to evaluate the effect of MTF on weight and cardiometabolic parameters in adults with overweight/obesity with or without nonalcoholic fatty liver disease (NAFLD) (CRD42018085512). We included randomized controlled trials (RCTs) in adults without diabetes mellitus, with mean body mass index (BMI) ≥ 25 kg/m2, with or without NAFLD, comparing MTF to placebo/control, lifestyle modification (LSM) or a US Food and Drug Administration-approved anti-obesity drug, reporting on weight or metabolic parameters, and extending over at least 3 months. We conducted a systematic search in MEDLINE, EMBASE, PubMed and the Cochrane Library without time limitation (until March 2022). We screened and selected eligible articles, abstracted relevant data, and assessed the risk of bias. All steps were in duplicate and independently. We conducted a random-effects model meta-analysis using Review Manager version 5.3, with prespecified subgroup analyses in case of heterogeneity. We identified 2650 citations and included 49 trials (55 publications). Compared to placebo, MTF was associated with a significant reduction in BMI (mean difference [MD] -0.56 [-0.74, -0.37] kg/m2; p < 0.0001), at doses ranging from 500 to 2550 mg/day, and with a significant percentage change in BMI of -2.53% (-2.90, -2.17) at the dose 1700 mg/day. There was no interaction by baseline BMI, MTF dose or duration, nor presence or absence of NAFLD. There was no significant difference between MTF and LSM. Orlistat was more effective than MTF (at doses of 1000-1700 mg/day) in terms of weight loss, with an MD in BMI of -3.17 (-5.88; -0.47) kg/m2, favouring the former. Compared to placebo/control, MTF improved insulin parameters, while no effect was detected when compared to LSM. A few small trials showed heterogenous effects on liver parameters in patients with NAFLD treated with MTF compared to placebo/control. There was a large variability in the expression of outcome measures and RCTs were of low quality. In conclusion, MTF was associated with a modest weight reduction in obese nondiabetic patients. Further high-quality and better powered studies are needed to examine the impact of MTF in patients with insulin resistance and NAFLD.

Development of canagliflozin nanocrystals sublingual tablets in the presence of sodium caprate permeability enhancer: formulation optimization, characterization, in-vitro, in silico, and in-vivo study.

Canagliflozin (CFZ) is a sodium-glucose cotransporter-2 inhibitor (SGLT2) that lowers albuminuria in type-2 diabetic patients, cardiovascular, kidney, and liver disease. CFZ is classified as class IV in the Biopharmaceutical Classification System (BCS) and is characterized by low permeability, solubility, and bioavailability, most likely attributed to hepatic first-pass metabolism. Nanocrystal-based sublingual formulations were developed in the presence of sodium caprate, as a wetting agent, and as a permeability enhancer. This formulation is suitable for children and adults and could enhance solubility, permeability, and avoid enterohepatic circulation due to absorption through the sublingual mucosa. In the present study, formulations containing various surfactants (P237, P338, PVA, and PVP K30) were prepared by the Sono-homo-assisted precipitation ion technique. The optimized formula prepared with PVP-K30 showed the smallest particle size (157 ± 0.32 nm), Zeta-potential (-18 ± 0.01), and morphology by TEM analysis. The optimized formula was subsequently formulated into a sublingual tablet containing Pharma burst-V® with a shorter disintegration time (51s) for the in-vivo study. The selected sublingual tablet improved histological and biochemical markers (blood glucose, liver, and kidney function), AMP-activated protein kinase (AMPK), and protein kinase B (AKT) pathway compared to the market formula, increased CFZ's antidiabetic potency in diabetic rabbits, boosted bioavailability by five-fold, and produced faster onset of action. These findings suggest successful treatment of diabetes with CFZ nanocrystal-sublingual tablets.

RAB27B Drives a Cancer Stem Cell Phenotype in NSCLC Cells Through Enhanced Extracellular Vesicle Secretion.

Cancer stem cells (CSC) within non-small cell lung carcinoma (NSCLC) tumors drive NSCLC progression, metastasis, relapse, and intrinsic chemoresistance. Understanding the mechanisms that support the malignant phenotypes of NSCLC CSCs may provide insights for improved NSCLC therapeutic interventions. Here, we report that expression of RAB27B, a small GTPase, is significantly upregulated in NSCLC CSCs when compared with bulk cancer cells (BCC). Short hairpin RNA-mediated knockdown of RAB27B leads to a loss of stem cell marker gene expression and reduced NSCLC spheroid growth, clonal expansion, transformed growth, invasion, and tumorigenicity. We find that NSCLC CSCs secrete significantly more extracellular vesicles (EV) than BCCs, and that this is RAB27B-dependent. Furthermore, CSC-derived EVs, but not BCC-derived EVs, induce spheroid growth, clonal expansion, and invasion in BCCs. Finally, RAB27B is required for CSC-derived EV-induced stemness in BCCs. Taken together, our results indicate that RAB27B is required for maintenance of a highly tumorigenic, cancer-initiating, invasive stem-like cell population in NSCLC and RAB27B is involved in propagating EV-mediated communication from NSCLC CSCs to BCCs. Our findings further suggest that inhibition of RAB27B-dependent EV secretion may be a potential therapeutic strategy for NSCLC. Significance: Expression of RAB27B in CSCs leads to elevated levels of EVs that mediate communication between CSCs and BCCs that maintains a stem-like phenotype in NSCLC cells.

Jordanian Undergraduate Students' Views of Participation in Clinical Trials: The COVID-19 Example.

The emergence of the COVID-19 pandemic has necessitated broad public participation in clinical trials. Knowledge of the attitudes of the relatively young would provide a perspective on future representative public enrollment in clinical trials. This study investigated the attitudes of undergraduate university students toward participation in COVID-19 clinical trials and determined the predictors of their attitudes. Using a validated, web-based questionnaire, 61.2% of the 425 respondents had heard about clinical trials before. Web-based media were the main sources of this knowledge. Less than 20% expressed willingness to participate in COVID-19 clinical trials or support the participation of a family member. The predictors were personal and family protection from the disease. On the contrary, being a female, possible political exploitation of the vaccine or drug, and their potential inefficacy were predictors of unwillingness to participate. This study may inform different stakeholders in developing effective study recruitment strategies to combat current and emerging pathogens.

The Protective and Therapeutic Anti-Alzheimer Potential of Olea europaea L. cv. Picual: An In Silico and In Vivo Study.

LC-HRESIMS metabolomic profiling of Olea europaea L. cv. Picual (OEP) (Saudi Arabian olive cultivar, F. Oleacea) revealed 18 compounds. Using pharmacology networking to specify the targets of the identified compounds with a relationship to Alzheimer's disease, it was possible to identify the VEGFA, AChE, and DRD2 genes as the top correlated genes to Alzheimer's disease with 8, 8, and 6 interactions in the same order. The mechanism of action on cellular components, biological processes, and molecular functions was determined by gene enrichment analysis. A biological pathway comparison revealed 13 shared pathways between the identified genes and Alzheimer protein genes (beta-amyloid band tau proteins). The suggested extract's anti-Alzheimer potential in silico screening was confirmed through in vivo investigation in regressing the neurodegenerative features of Alzheimer's dementia in an aluminum-intoxicated rat model (protective and therapeutic effects, 100 mg/kg b.w.). In vivo results suggested that OEP extract significantly improved Alzheimer's rats, which was indicated by the crude extract's ability to improve T-maze performance; lower elevated serum levels of AChE, AB peptide, and Ph/T ratio; and normalize the reduced level of TAC during the study. The results presented in this study may provide potential dietary supplements for the management of Alzheimer's disease.

Vitamin D Supplementation and Fractures in Adults: A Systematic Umbrella Review of Meta-Analyses of Controlled Trials.

CONTEXT: The growing number of systematic reviews/meta-analyses (SR/MAs) on vitamin D (±â€…calcium) for fracture prevention has led to contradictory guidelines. OBJECTIVE: This umbrella review aims to assess the quality and explore the reasons for the discrepancy of SR/MAs of trials on vitamin D supplementation for fracture risk reduction in adults. METHODS: We searched 4 databases (2010-2020), Epistemonikos, and references of included SRs/MAs, and we contacted experts in the field. We used A MeaSurement Tool to Assess systematic Reviews 2 (AMSTAR-2) for quality assessment. We compared results and investigated reasons for discordance using matrices and subgroup analyses (PROSPERO registration: CRD42019129540). We included 13 SR/MAs on vitamin D and calcium (Ca/D) and 19 SR/MAs on vitamin D alone, compared to placebo/control. RESULTS: Only 2 from 10 SRs/MAs on Ca/D were of moderate quality. Ca/D reduced the risk of hip fractures in 8 of 12 SRs/MAs (relative risk [RR] 0.61-0.84), and any fractures in 7 of 11 SR/MAs (RR 0.74-0.95). No fracture risk reduction was noted in SRs/MAs exclusively evaluating community-dwelling individuals or in those on vitamin D alone compared to placebo/control. Discordance in results between SRs/MAs stems from inclusion of different trials, related to search periods and eligibility criteria, and varying methodology (using intention to treat, per-protocol, or complete case analysis from individual trials). CONCLUSION: Ca/D reduces the risk of hip and any fractures, possibly driven by findings from institutionalized individuals. Individual participant data meta-analyses of patients on Ca/D with sufficient follow-up periods, and subgroup analyses, would unravel determinants for a beneficial response to supplementation.

Protective Effect of Nigella sativa and Onion Extract against 5-Fluorouracil-Induced Hepatic Toxicity.

Aim: The present study intended to compare the antioxidant, anti-lipid peroxidation, and anti-inflammatory potentials of Nigella Sativa (NS) and onion extract on 5-FU-induced liver damage in rats. Material and methods: 48 rats were divided into control, control group of the onion extract, control group of the NS extract, 5-FU-treated, concomitant NS-treated, and concomitant onion extract-treated. Liver sections were processed for histological analysis (light and electron microscopic examination). Liver enzymes (ALT, AST, and ALP), inflammatory markers (TNF-α and IL-1), antioxidant markers (SOD, GSH, and GSH/GSSG ratio), 4-HNE, NF-κB, and Nrf2 were evaluated. Results: The 5-FU-treated group exhibited inflammation, congested hepatic sinusoid, and steatosis. Improvement with few pathological residues was seen in the concomitant extract-treated groups. The 5-FU-treated group showed higher liver enzymes. The enzymes decreased in the concomitantly treated groups. 5-FU induced liver damage through oxidative stress, inflammation, and lipid peroxidation. Concomitantly using NS and onion extracts resulted in a reduction in oxidative stress, lipid peroxidation, and inflammation. Conclusion: NS and onion extracts attenuated 5-FU-induced liver damage via antioxidative, anti-lipid peroxidative, and anti-inflammatory mechanisms. NS's role was exceptional when compared with onion extract.

Risk of Postoperative Renal Failure in Radical Nephrectomy and Nephroureterectomy: A Validated Risk Prediction Model.

INTRODUCTION: The study aimed to construct and validate a risk prediction model for incidence of postoperative renal failure (PORF) following radical nephrectomy and nephroureterectomy. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database years 2005-2014 were used for the derivation cohort. A stepwise multivariate logistic regression analysis was conducted, and the final model was validated with an independent cohort from the ACS-NSQIP database years 2015-2017. RESULTS: In cohort of 14,519 patients, 296 (2.0%) developed PORF. The final 9-factor model included age, gender, diabetes, hypertension, BMI, preoperative creatinine, hematocrit, platelet count, and surgical approach. Model receiver-operator curve analysis provided a C-statistic of 0.79 (0.77, 0.82; p < 0.001), and overall calibration testing R2 was 0.99. Model performance in the validation cohort provided a C-statistic of 0.79 (0.76, 0.81; p < 0.001). CONCLUSION: PORF is a known risk factor for chronic kidney disease and cardiovascular morbidity, and is a common occurrence after unilateral kidney removal. The authors propose a robust and validated risk prediction model to aid in identification of high-risk patients and optimization of perioperative care.

Assessment of Multiple Sclerosis Awareness and Knowledge among the Community of Jeddah, Saudi Arabia.

Objective Multiple sclerosis (MS) is a degenerative disease of the central nervous system that can lead to lifelong disabilities. There is a significant increase in the global incidence of the disease. In Saudi Arabia (SA), the western region has the greatest number of MS cases. However, there is a lack of studies and research to assess public knowledge in the region. Thus, we aim to assess the public's knowledge of MS in Jeddah, SA. Methodology We conducted a cross-sectional study surveying 468 participants from the general population of Jeddah. A validated MS knowledge questionnaire (MSKQ-25) was used. Results Most participants were female 347 (74.1%) with a mean age of 35.73 ± 14.71 standard deviation (SD). MS was found in 14 (3%) of the participants. The average score of the (MSKQ) was 7.42 SD ± 4.568 versus the average score of people with MS with a mean of 13.92 SD ± 3.33 and a p value > 0.001. No significant variation was found in knowledge between gender and age groups, but there was a significant correlation between the educational level and the knowledge level. Conclusion The mean knowledge score was below average, which indicates poor knowledge of MS. Since the western region has the highest number of MS cases in SA, the level of understanding needs to increase. This can be improved by conducting educational programs using various types of media.

Vitamin D3 Dose Requirement That Raises 25-Hydroxyvitamin D to Desirable Level in Overweight and Obese Elderly.

CONTEXT: Guidelines for the dosage of vitamin D supplementation vary widely globally. OBJECTIVE: To investigate the impact of 2 vitamin D doses, bracketed between the IOM recommended dietary allowance (RDA) and the upper tolerable limit, on vitamin D nutritional status in elderly individuals. METHODS: This post hoc analysis of data collected from a 12-month, double-blind, randomized control trial included 221 ambulatory participants (≥ 65 years) with a mean BMI of 30.2 kg/m2 and a mean baseline serum 25-hydroxyvitamin D [25(OH)D] level of 20.4 ±â€…7.4 ng/mL, who were recruited from 3 outpatient centers in Lebanon. All participants received 1000 mg of elemental calcium daily from calcium citrate plus the daily equivalent of either 600 IU or 3750 IU of vitamin D3. RESULTS: Mean 25(OH)D level at 12 months was 26.0 ng/mL with low dose and 36.0 ng/mL with high dose vitamin D3. The proportion of participants reaching a value ≥ 20 ng/mL was 86% in the low dose, and 99% in the high dose arms, with no gender differences. The increment of 25(OH)D per 100 IU/day was 1 ng/mL with the low dose, and 0.41 ng/mL with the high dose. Serum 25(OH)D levels at 1 year were highly variable in both treatment arms. Baseline 25(OH)D level and vitamin D dose-but not age, BMI, gender, or season-were significant predictors of serum 25(OH)D level post-intervention. CONCLUSION: The IOM Recommended Dietary Allowance (RDA) of 600 IU/day does not bring 97.5% of ambulatory elderly individuals above the desirable threshold of 20 ng/mL. Country-specific RDAs are best derived taking into account the observed variability and predictors of achieved 25(OH)D levels.

Clinical heterogeneity of PLA2G6-related Parkinsonism: analysis of two Saudi families.

BACKGROUND: Recessive mutations in PLA2G6 have been associated with different neurodegenerative disorders, including infantile neuroaxonal dystrophy, neurodegeneration with brain iron accumulation and more recently, early-onset dystonia parkinsonism. METHOD: Targeted-next generation sequencing using a custom Neurology panel, containing 758 OMIM-listed genes implicated in neurological disorders, was carried out in two index cases from two different Saudi families displaying early-onset levodopa-responsive Parkinsonism with pyramidal signs and additional clinical features. The detected mutations were verified in the index cases and available family members by direct sequencing. RESULTS AND CONCLUSION: We identified a previously described PLA2G6 homozygous p.R741Q mutation in three affected and two asymptomatic individuals from two Saudi families. Our finding reinforces the notion of the broadness of the clinical spectrum of PLA2G6-related neurodegeneration.

Parkinson's Disease in Saudi Patients: A Genetic Study.

Parkinson's disease (PD) is one of the major causes of parkinsonism syndrome. Its characteristic motor symptoms are attributable to dopaminergic neurons loss in the midbrain. Genetic advances have highlighted underlying molecular mechanisms and provided clues to potential therapies. However, most of the studies focusing on the genetic component of PD have been performed on American, European and Asian populations, whereas Arab populations (excluding North African Arabs), particularly Saudis remain to be explored. Here we investigated the genetic causes of PD in Saudis by recruiting 98 PD-cases (sporadic and familial) and screening them for potential pathogenic mutations in PD-established genes; SNCA, PARKIN, PINK1, PARK7/DJ1, LRRK2 and other PD-associated genes using direct sequencing. To our surprise, the screening revealed only three pathogenic point mutations; two in PINK1 and one in PARKIN. In addition to mutational analysis, CNV and cDNA analysis was performed on a subset of patients. Exon/intron dosage alterations in PARKIN were detected and confirmed in 2 cases. Our study suggests that mutations in the ORF of the screened genes are not a common cause of PD in Saudi population; however, these findings by no means exclude the possibility that other genetic events such as gene expression/dosage alteration may be more common nor does it eliminate the possibility of the involvement of novel genes.

61-year-old man with sudden onset of gross hematuria: a case report.

A 61-year-old man with a medical history of gastroesophageal reflux disease presented with complaints of gross hematuria for 2 days and occasional epistaxis for 1 week. The medication list included only ranitidine. Laboratory data showed significantly elevated prothrombin time and international normalized ratio. The liver panel was normal. On inspection, the patient's bottle of ranitidine, which was refilled 20 days before, contained 5-mg tablets of warfarin. The international normalized ratio and prothrombin time were reversed with FFP, vitamin K, and Novoseven.

Prolonged pursuit by optokinetic drum testing in asymptomatic female carriers of novel FRMD7 splice mutation c.1050 +5 G>A.

OBJECTIVE: To determine the genotype underlying suspected X-linked infantile nystagmus in a family and to correlate genotype with clinical examination in potential female carriers. METHODS: Ophthalmic examination (ophthalmic, orthoptic, optokinetic [OKN] drum, and electrophysiologic when possible) and candidate gene analysis. RESULTS: Two affected brothers had infantile nystagmus with no evidence of associated visual or neurological disease. The symptomatic maternal aunt had infantile nystagmus in addition to congenital fibrosis of the extraocular muscles (CFEOM) (bilateral hypotropia, exotropia, ptosis, almost complete ophthalmoplegia, and poorly reactive pupils). A sister, the mother, and the maternal grandmother-all 3 of whom were asymptomatic-had delayed corrective saccades (prolonged pursuit) during OKN drum testing.A brother and the father­both of whom were asymptomatic­had unremarkable examination findings [corrected]. A FRMD7 splice variant (c.1050 + 5 G>A) was identified in the 2 affected brothers and in the 3 asymptomatic women only. Allele sharing analysis further confirmed that the aunt's phenotype was not related to the FRMD7 variant, which was absent in 246 ethnic controls. Her phenotype was also not related to mutation in known CFEOM genes (KIF21A, PHOX2A, TUBB3). CONCLUSIONS: Prolonged pursuit responses during OKN drum testing in asymptomatic female carriers is consistent with the concept of infantile nystagmus being an abnormally increased pursuit oscillation. Further studies are required to determine the reproducibility of this potential female carrier sign. Rather than being FRMD7 related, nystagmus in the maternal aunt represented a second disease in this family, likely related to CFEOM. CLINICAL RELEVANCE: Clinicians can use the OKN drum to assess obligate female carriers in a family suspected of having X-linked nystagmus.

Clinical and molecular characterization of ataxia with oculomotor apraxia patients in Saudi Arabia.

BACKGROUND: Autosomal recessive ataxias represent a group of clinically overlapping disorders. These include ataxia with oculomotor apraxia type1 (AOA1), ataxia with oculomotor apraxia type 2 (AOA2) and ataxia-telangiectasia-like disease (ATLD). Patients are mainly characterized by cerebellar ataxia and oculomotor apraxia. Although these forms are not quite distinctive phenotypically, different genes have been linked to these disorders. Mutations in the APTX gene were reported in AOA1 patients, mutations in SETX gene were reported in patients with AOA2 and mutations in MRE11 were identified in ATLD patients. In the present study we describe in detail the clinical features and results of genetic analysis of 9 patients from 4 Saudi families with ataxia and oculomotor apraxia. METHODS: This study was conducted in the period between 2005-2010 to clinically and molecularly characterize patients with AOA phenotype. Comprehensive sequencing of all coding exons of previously reported genes related to this disorder (APTX, SETX and MRE11). RESULTS: A novel nonsense truncating mutation c.6859 C > T, R2287X in SETX gene was identified in patients from one family with AOA2. The previously reported missense mutation W210C in MRE11 gene was identified in two families with autosomal recessive ataxia and oculomotor apraxia. CONCLUSION: Mutations in APTX , SETX and MRE11 are common in patients with autosomal recessive ataxia and oculomotor apraxia. The results of the comprehensive screening of these genes in 4 Saudi families identified mutations in SETX and MRE11 genes but failed to identify mutations in APTX gene.

Lack of KIF21A mutations in congenital fibrosis of the extraocular muscles type I patients from consanguineous Saudi Arabian families.

PURPOSE: Congenital fibrosis of the extraocular muscles type I (CFEOM1), the most common CFEOM worldwide, is characterized by bilateral ptotic hypotropia, an inability to supraduct above the horizontal midline, horizontal strabismus (typically exotropia), and ophthalmoplegia with abnormal synkinesis. This distinct non-syndromic phenotype is considered autosomal dominant and is virtually always from heterozygous missense mutations in kinesin family member 21A (KIF21A). However, there are occasional KIF21A-negative cases, opening the possibility for a recessive cause. The objective of this study is to explore this possibility by assessing CFEOM1 patients exclusively from consanguineous families, who are the most likely to have recessive cause for their phenotype if a recessive cause exists. METHODS: Ophthalmic examination and candidate gene direct sequencing (KIF21A, paired-like homeobox 2A [PHOX2A], tubulin beta-3 [TUBB3]) of CFEOM1 patients from consanguineous families referred for counseling from 2005 to 2010. RESULTS: All 5 probands had classic CFEOM1 as defined above. Three had siblings with CFEOM. None of the probands had mutations in KIF21A, PHOX2A, or TUBB3. CONCLUSIONS: The lack of KIF21A mutations in CFEOM1 patients exclusively from consanguineous families, most of whom had siblings with CFEOM, is strong evidence for a recessive form of CFEOM1. Further studies of such families will hopefully uncover the specific locus(loci).

Germline Mosaicism for KIF21A Mutation (p.R954L) Mimicking Recessive Inheritance for Congenital Fibrosis of the Extraocular Muscles.

OBJECTIVE: To document the genotype for familial congenital fibrosis of the extraocular muscles (CFEOM) with apparent autosomal recessive inheritance. DESIGN: Interventional family study. PARTICIPANTS: Two affected siblings, 3 asymptomatic siblings, and their 2 asymptomatic parents. METHODS: Ophthalmologic examination and candidate gene analysis (KIF21A and PHOX2A from venous blood samples) of the 2 affected siblings and their parents; confirmatory testing for 3 available asymptomatic siblings. MAIN OUTCOME MEASURES: Significant clinical observations and results of gene testing. RESULTS: The 2 affected siblings had large-angle exotropia, moderate bilateral hypotropia, moderate bilateral ptosis, sluggish pupils, and almost complete ophthalmoloplegia with some abnormal synkinesis. The asymptomatic parents were not related and had unremarkable ophthalmic examinations. Four other siblings were normal by history; 3 underwent venous blood sampling for confirmatory testing. Candidate gene testing of PHOX2A, the gene for recessive CFEOM (CFEOM2), did not reveal mutation in the 2 patients or their parents. Sequencing of KIF21A, the gene for dominant CFEOM (CFEOM1), revealed heterozygous p.R954L in both affected individuals but in not in their parents or 3 asymptomatic siblings, consistent with parental germline mosaicism. Haplotype analysis suggested paternal inheritance but was not conclusive. CONCLUSIONS: Parental germline mosaicism can mimic recessive inheritance in CFEOM and likely is underrecognized. Ophthalmologists should be aware of this phenomenon when counseling parents of children with apparent recessive (or de novo) hereditary eye disease. Unlike other reported KIF21A mutations that cause CFEOM1, the p.R954L variant seems to be associated with abnormal pupils. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Homozygous mutations in ADAMTS10 and ADAMTS17 cause lenticular myopia, ectopia lentis, glaucoma, spherophakia, and short stature.

Weill-Marchesani syndrome (WMS) is a well-characterized disorder in which patients develop eye and skeletal abnormalities. Autosomal-recessive and autosomal-dominant forms of WMS are caused by mutations in ADAMTS10 and FBN1 genes, respectively. Here we report on 13 patients from seven unrelated families from the Arabian Peninsula. These patients have a constellation of features that fall within the WMS spectrum and follow an autosomal-recessive mode of inheritance. Individuals who came from two families and met the diagnostic criteria for WMS were each found to have a different homozygous missense mutation in ADAMTS10. Linkage analysis and direct sequencing of candidate genes in another two families and a sporadic case with phenotypes best described as WMS-like led to the identification of three homozygous mutations in the closely related ADAMTS17 gene. Our clinical and genetic findings suggest that ADAMTS17 plays a role in crystalline lens zonules and connective tissue formation and that mutations in ADAMTS17 are sufficient to produce some of the main features typically described in WMS.