A case of dilated cardiomyopathy caused by FHL2 gene variant and a literature review / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical phenotype and genetic features of a child with dilated cardiomyopathy (DCM).@*METHODS@#Clinical data of the child who had presented at the Zhengzhou Children's Hospital on April 28, 2020 was collected. Trio-whole exome sequencing (trio-WES) was carried out for the child and her parents, and candidate variants were validated by Sanger sequencing. "FHL2" was taken as the key word to retrieve related literature from January 1, 1997 to October 31, 2021 in the PubMed database and was also searched in the ClinVar database as a supplement to analyze the correlation between genetic variants and clinical features.@*RESULTS@#The patient was a 5-month-old female infant presented with left ventricular enlargement and reduced systolic function. A heterozygous missense variant c.391C>T (p.Arg131Cys) in FHL2 gene was identified through trio-WES. The same variant was not detected in either of her parents. A total of 10 patients with FHL2 gene variants have been reported in the literature, 6 of them had presented with DCM, 2 with hypertrophic cardiomyopathy (HCM), and 2 with sudden unexplained death (SUD). Phenotypic analysis revealed that patients with variants in the LIM 3 domain presented hypertrophic cardiomyopathy and those with variants of the LIM 0~2 and LIM 4 domains had mainly presented DCM. The c.391C>T (p.Arg131Cys) has been identified in a child with DCM, though it has not been validated among the patient's family members. Based on the guidelines of the American College of Medical Genetics and Genomics, the c.391C>T(p.Arg131Cys) variant was re-classified as likely pathogenic (PS2+PM2_Supporting+PP3+PP5).@*CONCLUSION@#The heterozygous missense variant of c.391C>T (p.Arg131Cys) in the FHL2 gene probably predisposed to the DCM in this child, which has highlighted the importance of WES in the clinical diagnosis and genetic counseling.

Research progress on molecular genetics of male homosexuality / 中华医学遗传学杂志

Sexual orientation is influenced by both environmental factors and biological factors. Family and twin studies have shown that genetic factors play an important role in the formation of male homosexuality. Genome-wide scan also revealed candidate chromosomal regions which may be associated with male homosexuality, but so far no clearly related genes have been found. This article reviews the progress of relevant studies and candidate genes which are related to male homosexuality.

Recent advances in the research on mechanisms underlying podocyte-specific gene mutation-related steroid-resistant nephrotic syndrome / 中国当代儿科杂志

Steroid-resistant nephrotic syndrome poses a significant clinical challenge. Its pathogenesis has not been fully elucidated. In recent years, numerous studies have shown that podocyte-specific gene mutations may play important roles in the development of steroid-resistant nephrotic syndrome. Among the identified genes mutated in podocytes include NPHS2, NPHS1, WT1, TRPC6, MDR1, PLCE1, LMX1B, and LAMB2. This review aims to summarize the characteristics of these mutated genes in podocytes. The putative role for these podocyte-specific mutated genes in the pathogenesis, diagnosis, treatment and prognosis of steroid-resistant nephrotic syndrome is also discussed.

Association between two SNPs of ISL1 gene and congenital heart disease in children / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the association between 2 SNPs of ISL1 gene and congenital heart disease (CHD) in Tianjin Han children.</p><p><b>METHODS</b>Polymerase chain reaction and DNA sequencing were used to detect 2 SNPs at rs41268421 and rs1017 sites of ISL1 gene, including 35 CHD cases and 30 non-CHD controls. Differences of genotype and allele frequencies of rs41268421 and rs1017 sites were compared, and haplotype analysis of the two sites was performed.</p><p><b>RESULTS</b>Three genotypes (GG, GT and TT) were detected at ISL1 gene SNP rs41268421, and three genotypes (AA, AT and TT) were detected at SNP rs1017. At rs41268421, GT+TT genotypes and T allele frequencies in the CHD group were statistically higher than in the controls. The risk of CHD in children with T allele was significantly increased compared with children with G allele (OR=4.833). At rs1017, AT+TT genotypes and T allele frequencies in the CHD group were statistically higher than controls. The risk of CHD in children with T allele was greater compared with children with A allele (OR=4.491; P<0.05). Four kinds of haplotype were detected in the two SNPs sites and TT type increased the risk of CHD (OR=7.813).</p><p><b>CONCLUSIONS</b>Haplotype TT may increase the risk of CHD in Tianjin Han children.</p>

Construction of lentivirus vector containing human LIM mineralization protein-1 (LMP-1) and its expression in rat bone mesenchymal stem cells / 中国骨伤

<p><b>OBJECTIVE</b>To construct a recombiant lentivirus vector of human LMP-1 and detect the expression of LMP-1 in infected rat bone mesenchymal stem cells.</p><p><b>METHODS</b>LMP-1 gene from the cDNA library were extracted by Polymerase Chain Reaction (PCR). The LMP-1 genes were connected into lentiviral vectors pGC-FU-EGFP which was linearized by Age I enzyme to produce recombiant lentivirus vector called as pGC-FU-LMP-1-EGFP,then packaged by 293T cells. The virus supernant congtaining LV-LMP-1-EGFP was harvested, concentrated and titrated. The rat BMSCs were transfected with recombiant lentivirus LV-LMP-1-EGFP at the most appropriate MOI. The mRNA and protein expression of LMP-1 were detected by RT-PCR and Western blot.</p><p><b>RESULTS</b>1LV-LMP-1I-EGFP was recombined successfully and the titer reached 2x108TU/ml. 2The efficiency of infection was 93.5% ,which was get after LV-LMP-1-EGFP infected rat BMSCs at the most appropriate MOI=100. The expression of LMP-1 gene was confirmed by RT-PCR and Western blot.</p><p><b>CONCLUSION</b>Lentivirus vector containing human LMP-1 gene is constructed successfully,which can transfected efficiently into rat BMSCs,and the infected rat BMSCs can effectively express LMP-1.</p>

FHL2 inhibits the Id3-promoted proliferation and invasive growth of human MCF-7 breast cancer cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Id3 plays a key role in the progression of breast cancer. Previously, four and a half LIM protein (FHL2) was identified as a repressor of Id family proteins by interacting with them. This study aimed to investigate the effects of FHL2 on the transcriptional regulation and oncogenic activities of Id3 in human breast cancer cells.</p><p><b>METHODS</b>Cell transfection was performed with SuperFect reagent. Stable transfectants that overexpressed Id3 were obtained by selection on G418. The level of Id3 protein was determined by Western blotting analysis. Dual luciferase assays were used to measure the effect of Id3 and FHL2 on E47-mediated transcriptional activity in MCF-7 human breast cancer cells. The MTT assay was used to measure cell proliferation. The transwell assay was used to measure the invasive capacity of MCF-7 cancer cells.</p><p><b>RESULTS</b>Id3 markedly repressed transcription mediated by the basic helix-loop-helix (bHLH) factor E47 in MCF-7 cells. This Id3-mediated repression was effectively antagonized by FHL2. Overexpression of Id3 markedly promoted the proliferation and invasive capacity of MCF-7 cells; however, these effects were significantly suppressed by the overexpression of FHL2.</p><p><b>CONCLUSIONS</b>FHL2 can inhibit the proliferation and invasive growth of human breast cancer cells by repressing the functional activity of Id3. The functional roles of FHL2-Id3 signaling in the development of human breast cancer need further research.</p>

Expression of FHL2 during mineralization of human periodontal ligament cells in vitro / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression pattern of FHL2, which is an intracellular signaling transcription molecule during mineralization in cultured human periodontal ligament cells (hPDLCs) in vitro.</p><p><b>METHODS</b>hPDLCs were cultured in vitro. Test group was cultured with mineral induction media while control group without induction media. 0, 14, 28 days after culture, alizarin red staining was used to measure the mineral nodules formation. Immunocytochemistry was used to examine the expression of FHL2 protein 0 day and 14 days after mineral induction. Meanwhile, mRNA expression level of FHL2 was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) on the 0, 14, 28 days after induction.</p><p><b>RESULTS</b>14 and 28 days after cultivation, mineral nodules formed and were stained positively with alizarin red staining in test group while no mineral nodule formed in control group. Immunocytochemical results indicated that hPDLCs in test group expressed FHL2 positively. According to RT-PCR results, 14 and 28 days after mineral induction, the expression levels of FHL2 both increased significantly when compared with 0 day (P<0.01), and the expression level at 14 days was 1.4 folds of 0 day.</p><p><b>CONCLUSION</b>FHL2 protein is found to be involved in the in vitro mineralization of hPDLCs. FHL2 protein may play a role in the differentiation and mineralization of hPDLCs.</p>

Dexamethasone inhibits osteoblastic differentiation by down-regulation of LIM mineralization protein 1 / 生理学报

To investigate the mechanisms of the inhibition of osteoblastic differentiation by dexamethasone (DEX), the effects of different doses of DEX on the activity of alkaline phosphatase (ALP), the synthesis of osteocalcin (OC) and the expression of collagen type I were observed in the cultured rat osteoblasts. The LIM mineralization protein-1 (LMP-1) mRNA, a positive regulator of osteoblasts, was semi-quantified by RT-PCR. The results showed that a lower dose (10(-9) mol/L) of DEX could enhance the activity of ALP, the synthesis of OC and the expression of collagen type I. However, a higher dose (10(-7) mol/L) of DEX inhibited them and down-regulated the expression of LMP-1 mRNA in osteoblasts. It is suggested that DEX stimulates osteoblast differentiation at lower dose, while at higher dose it inhibits osteoblast differentiation. The inhibitory action of DEX on osteoblast differentiation might be mediated by the down-regulation of LMP-1 mRNA.