Complex genotype-phenotype correlation of MYH11: new insights from monozygotic twins with highly variable expressivity and outcomes.

BACKGROUND: Thoracic aortic aneurysm/dissection (TAAD) and patent ductus arteriosus (PDA) are serious autosomal-dominant diseases affecting the cardiovascular system. They are mainly caused by variants in the MYH11 gene, which encodes the heavy chain of myosin 11. The aim of this study was to evaluate the genotype-phenotype correlation of MYH11 from a distinctive perspective based on a pair of monozygotic twins. METHODS: The detailed phenotypic characteristics of the monozygotic twins from the early fetal stage to the infancy stage were traced and compared with each other and with those of previously documented cases. Whole-exome and Sanger sequencing techniques were used to identify and validate the candidate variants, facilitating the analysis of the genotype-phenotype correlation of MYH11. RESULTS: The monozygotic twins were premature and presented with PDA, pulmonary hypoplasia, and pulmonary hypertension. The proband developed heart and brain abnormalities during the fetal stage and died at 18 days after birth, whereas his sibling was discharged after being cured and developed normally post follow-up. A novel variant c.766 A > G p. (Ile256Val) in MYH11 (NM_002474.2) was identified in the monozygotic twins and classified as a likely pathogenic variant according to the American College of Medical Genetics/Association for Molecular Pathology guidelines. Reviewing the reported cases (n = 102) showed that the penetrance of MYH11 was 82.35%, and the most common feature was TAAD (41.18%), followed by PDA (22.55%), compound TAAD and PDA (9.80%), and other vascular abnormalities (8.82%). The constituent ratios of null variants among the cases with TAAD (8.60%), PDA (43.8%), or compound TAAD and PDA (28.6%) were significantly different (P = 0.01). Further pairwise comparison of the ratios among these groups showed that there were significant differences between the TAAD and PDA groups (P = 0.006). CONCLUSION: This study expands the mutational spectrum of MYH11 and provides new insights into the genotype-phenotype correlation of MYH11 based on the monozygotic twins with variable clinical features and outcomes, indicating that cryptic modifiers and complex mechanisms beside the genetic variants may be involved in the condition.

Histological study of telocytes in mice intrauterine adhesion model and their positive effect on mesenchymal stem cells in vitro.

Intrauterine adhesions (IUA), the main cause of secondary infertility in women, result from irreversible fibrotic repair of the endometrium due to inflammation or human factors, accompanied by disruptions in the repair function of endometrial stem cells. This significantly impacts the physical and mental health of women in their childbearing years. Telocytes (TCs), a distinctive type of interstitial cells found in various tissues and organs, play diverse repair functions due to their unique spatial structure. In this study, we conduct the inaugural exploration of the changes in TCs in IUA disease and their potential impact on the function of stem cells. Our results show that in vivo, through double immunofluorescence staining (CD34+/Vimentin+; CD34+/CD31-), as endometrial fibrosis deepens, the number of TCs gradually decreases, telopodes shorten, and the three-dimensional structure becomes disrupted in the mouse IUA mode. In vitro, TCs can promote the proliferation and cycle of bone mesenchymal stem cells (BMSCs) by promoting the Wnt/ß-catenin signaling pathway, which were inhibited using XAV939. TCs can promote the migrated ability of BMSCs and contribute to the repair of stem cells during endometrial injury. In addition, TCs can inhibit the apoptosis of BMSCs through the Bcl-2/Bax pathway. In conclusion, our study demonstrates, for the first time, the resistance role of TCs in IUA disease, shedding light on their potential involvement in endometrial repair through the modulation of stem cell function.

[Analysis of a child with DIGFAN syndrome due to variant of MORC2 gene].

OBJECTIVE: To explore the clinical features and genetic etiology for a child with developmental delay, impaired growth, facial dysmorphism, and axonal neuropathy (DIGFAN). METHODS: A child who was admitted to the Second Affiliated Hospital of Guangxi Medical University on March 22, 2021 was selected the study subject. Clinical data of the child was collected. Following extraction of genomic DNA, the child and his parents were subjected to whole exome sequencing (WES), and candidate variant was verified by Sanger sequencing and bioinformatic analysis. RESULTS: The child, a 10-year-and-9-month-old boy, had manifested with short stature, intellectual disability, delayed speech, motor and language development, and facial dysmorphism. WES and Sanger sequencing revealed that he has harbored a novel de novo c.800T>C (p.Leu267Pro) variant of the MORC2 gene. The Leucine at position 267, which is highly conserved among various species, is located in the S5 domain of ribosome protein in the ATPase binding region of MORC2. And the Leu267Pro may affect the function of MORC2 by altering the spatial conformation and activity of ATPase. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.800T>C variant was classified as likely pathogenic (PS2+PM2_Supporting+PP2+PP3). CONCLUSION: The MORC2: c.800T>C (p.Leu267Pro) variant probably underlay the pathogenesis of DIGFAN syndrome in this child.

Telocyte-Derived Exosomes Provide an Important Source of Wnts That Inhibits Fibrosis and Supports Regeneration and Repair of Endometrium.

Intrauterine adhesions (IUAs) often occurred after common obstetrical and gynecological procedures or infections in women of reproductive age. It was characterized by the formation of endometrial fibrosis and prevention of endometrial regeneration, usually with devastating fertility consequences and poor treatment outcomes so far. Telocytes (TCs), as a novel interstitial cell type, present in female uterus with in vitro therapeutic potential in decidualization-defective gynecologic diseases. This study aims to further investigate the role of TC-derived Wnt ligands carried by exosomes (Exo) in reversal of fibrosis and enhancement of regeneration repair in endometrium. IUA cellular and animal models were established from endometrial stromal cells (ESCs) and mice, followed with treatment of TC-conditioned medium (TCM) or TC-derived Exo. In cellular model, fibrosis markers (collagen type 1 alpha 1 [COL1A1], fibronectin [FN], and α-smooth muscle actin [α-SMA]), angiogenesis (vascular endothelial growth factor [VEGF]), and pathway protein (ß-catenin) were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blotting (WB), and immunofluorescence. Results showed that, TCs (either TCM or TC-derived Exo) provide a source of Wnts that inhibit cellular fibrosis, as evidenced by significantly elevated VEGF and ß-catenin with decreased fibrotic markers, whereas TCs lost salvage on fibrosis after being blocked with Wnt/ß-catenin inhibitors (XAV939 or ETC-159). Further in mouse model, regeneration repair (endometrial thickness, number of glands, and fibrosis area ratio), fibrosis markers (fibronectin [FN]), mesenchymal-epithelial transition (MET) (E-cadherin, N-cadherin), and angiogenesis (VEGF, microvessel density [MVD]) were studied by hematoxylin-eosin (HE), Masson staining, and immunohistochemistry. Results demonstrated that TC-Exo treatment effectively promotes regeneration repair of endometrium by relieving fibrosis, enhancing MET, and angiogenesis. These results confirmed new evidence for therapeutic perspective of TC-derived Exo in IUAs.

Inhibitory effect of telocyte-induced M1 macrophages on endometriosis: Targeting angiogenesis and invasion.

PURPOSE: Telocytes (TCs), a novel type of stromal cells found in tissues, induce macrophage differentiation into classically activated macrophages (M1) types and enhance their phagocytic function. The purpose of this study was to investigate the inhibitory effects of TC-induced M1 macrophages on endometriosis (EMs). METHODS: mouse uterine primary TCs and endometrial stromal cells (ESCs) were isolated and identified using double immunofluorescence staining. For the in vitro study, ESCs were treated with TC-induced M1 macrophages, and the vascular endothelial growth factor (VEGF), matrix metalloproteinase 9 (MMP9), and nuclear factor kappa B (NF-κb) genes were identified by quantitative real-time PCR (qRT-PCR) or western blotting (WB). For the in vivo study, an EMs mouse model received TC-conditioned medium (TCM) via abdominal administration, and characterized the inhibitory effects on growth (lesion weight, volume, and pathology), tissue-resident macrophages differentiation by immunostaining, angiogenic capacity (CD31 and VEGF), invasive capacity (MMP9), and NF-κb expression within EMs lesions. RESULTS: immunofluorescent staining showed that uterine TCs expressed CD34+ and vimentin+, whereas ESCs expressed vimentin+ and cytokeratin-. At the cellular level, TC-induced M1 macrophages can significantly inhibit the expression of VEGF and MMP9 in ESCs through WB or qRT-PCR, possibly by suppressing the NF-κb pathway. The in vivo study showed that macrophages switch from the alternatively activated macrophages (M2) in untreated EMs lesions to the M1 subtype after TCM exposure. Thereby, TC-induced M1 macrophages contributed to the inhibition of EMs lesions. More importantly, this effect may be achieved by suppressing the expression of NF-κb to inhibit angiogenesis (CD31 and VEGF) and invasion (MMP9) in the tissue. CONCLUSION: TC-induced M1 macrophages play a prevailing role in suppressing EMs by inhibiting angiogenic and invasive capacity through the NF-κb pathway, which provides a promising therapeutic approach for EMs.

Case report: A novel heterozygous synonymous variant in deep exon region of NIPBL gene generating a non-canonical splice donor in a patient with cornelia de lange syndrome.

Cornelia de Lange syndrome (CdLS) is an autosomal dominant or X-linked genetic disease with significant genetic heterogeneity. Variants of the NIPBL gene are responsible for CdLS in 60% of patients. Herein, we report the case of a patient with CdLS showing distinctive facial features, microcephaly, developmental delay, and growth retardation. Whole exome sequencing was performed for the patient, and a novel de novo heterozygous synonymous variant was identified in the deep region of exon 40 in the NIPBL gene (NM_133433.4: c. 6819G > T, p. Gly2273 = ). The clinical significance of the variant was uncertain according to the ACMG/AMP guidelines; however, based on in silico analysis, it was predicted to alter mRNA splicing. To validate the prediction, a reverse transcriptase-polymerase chain reaction was conducted. The variant activated a cryptic splice donor, generating a short transcript of NIPBL. A loss of 137 bp at the 3' end of NIPBL exon 40 was detected, which potentially altered the open reading frame by inserting multiple premature termination codons. Quantitative real-time PCR analysis showed that the ratio of the transcription level of the full-length transcript to that of the altered short transcript in the patient was 5:1, instead of 1:1. These findings may explain the relatively mild phenotype of the patient, regardless of the loss of function of the truncated protein due to a frameshift in the mRNA. To the best of our knowledge, this study is the first to report a synonymous variant in the deep exon regions of the NIPBL gene responsible for CdLS. The identified variant expands the mutational spectrum of the NIPBL gene. Furthermore, synonymous variations may be pathogenic, which should not be ignored in the clinical and genetic diagnosis of the disease.

Telocytes in Fibrosis Diseases: From Current Findings to Future Clinical Perspectives.

Telocytes (TCs), a distinct type of interstitial (stromal) cells, have been discovered in many organs of human and mammal animals. TCs, which have unique morphological characteristics and abundant paracrine substance, construct a three-dimensional (3D) interstitial network within the stromal compartment by homocellular and heterocellular communications which are important for tissue homeostasis and normal development. Fibrosis-related diseases remain a common but challenging problem in the field of medicine with unclear pathogenesis and limited therapeutic options. Recently, increasing evidences suggest that where TCs are morphologically or numerically destructed, many diseases continuously develop, finally lead to irreversible interstitial fibrosis. It is not difficult to find that TCs are associated with chronic inflammation and fibrosis. This review mainly discusses relationship between TCs and the occurrence of fibrosis in various diseases. We analyzed in detail the potential roles and speculated mechanisms of TCs in onset and progression of systemic fibrosis diseases, as well as providing the most up-to-date research on the current therapeutic roles of TCs and involved related pathways. Only through continuous research and exploration in the future can we uncover its magic veil and provide strategies for treatment of fibrosis-related disease.

Risk Score Based on Two microRNAs as a Prognostic Marker of Hepatocellular Carcinoma and the Corresponding Competitive Endogenous RNA Network.

PURPOSE: Liver transplantation (LT) currently yields the best outcomes for hepatocellular carcinoma (HCC). However, tumor recurrence still occurs in some patients. Identifying markers that predict HCC recurrence after LT is an unmet medical need. METHODS: In this study, differential expression analysis was used to identify differentially expressed microRNAs (DEmiRs) between HCC and liver tissues in the The Cancer Genome Atlas database and in data from patients with recurrent or non-recurrent HCC in the GSE64989 dataset. The expression profiles of the overlap DEmiRs were used to construct an miRNA-based risk score to predict prognosis using Cox regression analysis. The target genes of the miRNAs of interest were predicted, and they were analyzed for functional enrichment. Furthermore, we used the miRNAs of interest to construct a competitive endogenous RNA (ceRNA) network of long non-coding RNAs (lncRNAs), miRs and mRNAs. RESULTS: Four up-regulated and three down-regulated miRNAs in HCC and recurrent HCC after LT were considered as candidate miRs. MiR-3200-3p and miR-3690 were selected to construct the miR-based risk score, which was found to be associated with poor overall survival and progression-free survival. Furthermore, it proved to be an independent prognostic factor after adjusting for other clinicopathological factors. The corresponding ceRNA networks of these two miRs that we constructed may help to understand their regulatory mechanisms in HCC. CONCLUSION: We propose a risk score based on miR-3200-3p and miR-3690 that may be useful as a prognostic marker to predict HCC recurrence after LT. We generated a ceRNA network involving these miRNAs, which may help reveal their regulatory roles in HCC.