Congenital bilateral absence of the vas deferens (CBAVD) is observed in 1%-2% of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator (CFTR) mutations. CFTR is one of the most well-known genes related to male fertility. The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia (NOA). CFTR mutations are highly polymorphic and have established ethnic specificity. Compared with F508Del in Caucasians, the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis. However, whether p.G970D participates in male infertility remains unknown. Herein, a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA. Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation (4.1%, 5/122), excluding polymorphic sites. Furthermore, we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients. The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells. In spermatocyte GC-2(spd)ts (GC2) Cftr p.G965D cells, RNA splicing variants were detected and CFTR expression decreased, which may contribute to the phenotypes associated with impaired spermatogenesis. Thus, this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.
Humans ; Animals ; Mice ; Male ; Mutation, Missense ; Retrospective Studies ; Cystic Fibrosis Transmembrane Conductance Regulator/genetics* ; Infertility, Male/genetics* ; Mutation ; Vas Deferens/abnormalities* ; Spermatogenesis/genetics*

Male ; Humans ; Mutation, Missense ; Cystic Fibrosis Transmembrane Conductance Regulator/genetics* ; Infertility, Male/genetics* ; Genetic Testing ; Mutation ; Vas Deferens

Cystic fibrosis (CF) is a rare autosomal recessive disease with only one pathogenic gene cystic fibrosis transmembrane conductance regulator (CFTR). To identify the potential pathogenic mutations in a Chinese patient with CF, we conducted Sanger sequencing on the genomic DNA of the patient and his parents and detected all 27 coding exons of CFTR and their flanking intronic regions. The patient is a compound heterozygote of c.2909G > A, p.Gly970Asp in exon 18 and c.1210-3C > G in cis with a poly-T of 5T (T5) sequence, 3 bp upstream in intron 9. The splicing effect of c.1210-3C > G was verified via minigene assay in vitro, indicating that wild-type plasmid containing c.1210-3C together with T7 sequence produced a normal transcript and partial exon 10-skipping-transcript, whereas mutant plasmid containing c.1210-3G in cis with T5 sequence caused almost all mRNA to skip exon 10. Overall, c.1210-3C > G, the newly identified pathogenic mutation in our patient, in combination with T5 sequence in cis, affects the CFTR gene splicing and produces nearly no normal transcript in vitro. Moreover, this patient carries a p.Gly970Asp mutation, thus confirming the high-frequency of this mutation in Chinese patients with CF.
China ; Cystic Fibrosis/genetics* ; Cystic Fibrosis Transmembrane Conductance Regulator/genetics* ; Humans ; Mutation ; Poly T ; RNA, Messenger/genetics*

OBJECTIVES: To study the clinical features and gene mutation sites of children with cystic fibrosis (CF), in order to improve the understanding of CF to reduce misdiagnosis and missed diagnosis. METHODS: A retrospective analysis was performed on the medical records of 8 children with CF who were diagnosed in Hebei Children's Hospital from 2018 to 2021. RESULTS: Among the 8 children with CF, there were 5 boys and 3 girls, with an age of 3-48 months (median 8 months) at diagnosis, and the age of onset ranged from 0 to 24 months (median 2.5 months). Clinical manifestations included recurrent respiratory infection in 7 children, sinusitis in 3 children, bronchiectasis in 4 children, diarrhea in 8 children, fatty diarrhea in 3 children, suspected pancreatic insufficiency in 6 children, pancreatic cystic fibrosis in 1 child, malnutrition in 5 children, and pseudo-Bartter syndrome in 4 children. The most common respiratory pathogens were Pseudomonas aeruginosa (4 children). A total of 16 mutation sites were identified by high-throughput sequencing, multiplex ligation-dependent probe amplification, and Sanger sequencing, including 5 frameshift mutations, 4 nonsense mutations, 4 missense mutations, 2 exon deletions, and 1 splice mutation. CFTR mutations were found in all 8 children. p.G970D was the most common mutation (3 children), and F508del mutation was observed in one child. Four novel mutations were noted: deletion exon15, c.3796_3797dupGA(p.I1267Kfs*12), c.2328dupA(p.V777Sfs*2), and c.2950G>A(p.D984N). CONCLUSIONS p.G970D is the most common mutation type in children with CF. CF should be considered for children who have recurrent respiratory infection or test positive for Pseudomonas aeruginosa, with or without digestive manifestations or pseudo-Bartter syndrome.
Bartter Syndrome ; Child, Preschool ; Cystic Fibrosis/genetics* ; Cystic Fibrosis Transmembrane Conductance Regulator/genetics* ; Diarrhea ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Mutation ; Respiratory Tract Infections ; Retrospective Studies

Cystic fibrosis (CF) is a fatal autosomal-recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. CF is characterized by recurrent pulmonary infection with obstructive pulmonary disease. CF is common in the Caucasian population but is rare in the Chinese population. The symptoms of early-stage CF are often untypical and may sometimes manifest as Bartter syndrome (BS)-like hypokalemic alkalosis. Therefore, the ability of doctors to differentiate CF from BS-like hypokalemic alkalosis in Chinese infants is a great challenge in the timely and accurate diagnosis of CF. In China, sporadic CF has not been diagnosed in children younger than three years of age to date. Three infants, who were initially admitted to our hospital over the period of June 2013 to September 2014 with BS-like hypokalemic alkalosis, were diagnosed with CF through exome sequencing and sweat chloride measurement. The compound heterozygous mutations of the CFTR gene were detected in two infants, and a homozygous missense mutation was found in one infant. Among the six identified mutations, two are novel point mutations (c.1526G > C and c.3062C > T) that are possibly pathogenic. The three infants are the youngest Chinese patients to have been diagnosed with sporadic CF at a very early stage. Follow-up examination showed that all of the cases remained symptom-free after early intervention, indicating the potential benefit of very early diagnosis and timely intervention in children with CF. Our results demonstrate the necessity of distinguishing CF from BS in Chinese infants with hypokalemic alkalosis and the significant diagnostic value of powerful exome sequencing for rare genetic diseases. Furthermore, our findings expand the CFTR mutation spectrum associated with CF.
Alkalosis ; complications ; Bartter Syndrome ; China ; Cystic Fibrosis ; diagnosis ; genetics ; Cystic Fibrosis Transmembrane Conductance Regulator ; genetics ; Diagnosis, Differential ; Exome ; Female ; Humans ; Hypokalemia ; complications ; Infant ; Male ; Mutation

BACKGROUND: The incidence of lung cancer is gradually increased, and the cystic fibrosis transmembrane conductance regulator (CFTR) has recently demonstrated to have an implication in the deoncogenesis and malignant transformation of many types of cancers. The aim of this study is to investigate impacts of CFTR on the malignant features of lung adenocarcinoma A549 cells. METHODS: The capacity of cell proliferation, migration, invasion and clonogenicity of non-small cell lung cancer A549 cells were detected by CCK8 cell proliferation assay, cell scratch assay, Transwell cell invasion assay and clone formation assay, respectively. Meanwhile, the effect of CFTR gene on the expression of cancer stem cell related transcriptional factors was also detected by immunoblotting (Western blot) assay. RESULTS: An overexpression of CFTR gene in A549 cells significantly inhibited the malignant capacity of A549 cells, including potencies of cell proliferation, migration, invasion and colony formation; while knockdown of CFTR gene expression by RNA interference in A549 cells resulted in an opposite effect seen in above cells overexpressing CFTR gene. Mechanistically, immunoblotting assay further revealed that the ectopic expression of CFTR gene led an inhibitory expression of stem cell-related transcriptional factors SOX2 and OCT3/4, and cancer stem cell surface marker CD133 in A549 cells, while a knockdown of CFTR expression yielded a moderately increased expression of these gene. However, an alteration of CFTR gene expression had neither effect on the expression of putative lung cancer stem cell marker aldehyde dehydrogenase1 (ALDH1), nor the frequency of ALDH1A-positive cells in A549 cells, as ascertained by the immunoblotting assay and cytometry analysis, respectively. CONCLUSIONS The CFTR exhibited an inhibitory role in the malignancy of lung adenocarcinoma A549 cells, suggesting that it may be a novel potential target for lung cancer treatment. However, its functions in other lung adenocarcinoma cell lines and its underlying molecular mechanisms require further investigation.
A549 Cells ; Adenocarcinoma ; pathology ; Adenocarcinoma of Lung ; Cell Movement ; genetics ; Cell Proliferation ; genetics ; Cystic Fibrosis Transmembrane Conductance Regulator ; metabolism ; Humans ; Lung Neoplasms ; pathology ; Mutation ; Neoplasm Invasiveness ; Neoplastic Stem Cells ; pathology ; Proto-Oncogene Proteins p21(ras) ; genetics

BACKGROUND: This study aimed to identify pathogenic variants of PRSS1, SPINK1, CFTR, and CTRC genes in Korean patients with idiopathic pancreatitis. METHODS: The study population consisted of 116 Korean subjects (65 males, 51 females; mean age, 30.4 yr, range, 1-88 yr) diagnosed with idiopathic chronic pancreatitis (ICP), idiopathic recurrent acute pancreatitis (IRAP), or idiopathic acute pancreatitis (IAP). We analyzed sequences of targeted regions in the PRSS1, SPINK1, CFTR, and CTRC genes, copy numbers of PRSS1 and SPINK1, and clinical data from medical records. RESULTS: We identified three types of pathogenic PRSS1 variants in 11 patients, including p.N29I (n=1), p.R122H (n=1), and p.G208A (n=9). Sixteen patients exhibited heterozygous pathogenic variants of SPINK1, including c.194+2T>C (n=12), p.N34S (n=3), and a novel pathogenic splicing variation c.194+1G>A. A heterozygous CFTR p.Q1352H pathogenic variant was detected in eight patients. One patient carried a heterozygous CTRC p.P249L pathogenic variant, which is a known high-risk variant for pancreatitis. All patients had normal PRSS1 and SPINK1 gene copy numbers. Weight loss occurred more frequently in patients carrying the p.G208A pathogenic variant, while pancreatic duct stones occurred more frequently in patients with the c.194+2T>C pathogenic variant. CONCLUSIONS: Pathogenic variants of PRSS1, SPINK1, and CFTR were associated with idiopathic pancreatitis, while pathogenic variants of CTRC were not. Copy number variations of PRSS1 and SPINK1 were not detected.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Asian Continental Ancestry Group/*genetics ; Carrier Proteins/*genetics ; Child ; Child, Preschool ; Chymotrypsin/*genetics ; Cystic Fibrosis Transmembrane Conductance Regulator/*genetics ; DNA Copy Number Variations ; Female ; Heterozygote ; Humans ; Infant ; Male ; Middle Aged ; Pancreatitis, Chronic/*genetics/pathology ; Polymorphism, Genetic ; Republic of Korea ; Trypsin/*genetics ; Young Adult

OBJECTIVETo discuss the results and significance of the detection of the CFTR gene mutation in azoospermia patients with congenital unilateral absence of the vas deferens (CUAVD).

METHODSWe collected peripheral blood samples from 6 azoospermia patients with CUAVD for detection of the CFTR gene mutations and single nucleotide polymorphisms. We analyzed the genome sequences of the CFTR gene in comparison with the website of the UCSC Genome Browser on Human Dec. 2013 Assembly.

RESULTSMissense mutation of c. 592G > C in exon 6 was found in 1 of the 6 azoospermia patients with CUAVD and splicing mutation of c. 1210-12T[5] was observed in the noncoding region before exon 10 in 2 of the patients, both with the V470 haplotype in exon 11.

CONCLUSIONMutations of the CFTR gene can be detected in azoospermia patients with CUAVD and the detection of the CFTR gene mutation is necessary for these patients.

Azoospermia ; genetics ; Cystic Fibrosis Transmembrane Conductance Regulator ; genetics ; Exons ; Humans ; Male ; Male Urogenital Diseases ; genetics ; Mutation, Missense ; genetics ; Vas Deferens ; abnormalities

OBJECTIVETo focus on the asthmatic pathogenesis and clinical manifestations related to epithelial sodium channel (ENaC)/chlorine ion channel.

DATA SOURCESThe data analyzed in this review were the English articles from 1980 to 2015 from journal databases, primarily PubMed and Google Scholar. The terms used in the literature search were: (1) ENaCs; cystic fibrosis (CF) transmembrane conductance regulator (CFTR); asthma/asthmatic, (2) ENaC/sodium salt; CF; asthma/asthmatic, (3) CFTR/chlorine ion channels; asthma/asthmatic, (4) ENaC/sodium channel/scnn1a/scnn1b/scnn1g/scnn1d/amiloride-sensitive/amiloride-inhibtable sodium channels/sodium salt; asthma/asthmatic, lung/pulmonary/respiratory/tracheal/alveolar, and (5) CFTR; CF; asthma/asthmatic (ti).

STUDY SELECTIONThese studies included randomized controlled trials or studies covering asthma pathogenesis and clinical manifestations related to ENaC/chlorine ion channels within the last 25 years (from 1990 to 2015). The data involving chronic obstructive pulmonary disease and CF obtained from individual studies were also reviewed by the authors.

RESULTSAirway surface liquid dehydration can cause airway inflammation and obstruction. ENaC and CFTR are closely related to the airway mucociliary clearance. Ion transporters may play a critical role in pathogenesis of asthmatic exacerbations.

CONCLUSIONSIon channels have been the center of many studies aiming to understand asthmatic pathophysiological mechanisms or to identify therapeutic targets for better control of the disease.

Asthma ; physiopathology ; Chloride Channels ; physiology ; Cystic Fibrosis ; genetics ; Cystic Fibrosis Transmembrane Conductance Regulator ; genetics ; Epithelium ; physiopathology ; Humans ; Respiratory System ; physiopathology ; Sodium Channels ; physiology

OBJECTIVETo determine the expression pattern of Slc26a3 gene in reproductive tract of male rodents to clarify whether the expression pattern is related to the subfertility observed in congenital chloride diarrhea (CLD) disease.

METHODSThe expression of Slc26a3 in mouse and rat epididymis has been studied with immunohistochemistry and Western blotting. Its developmental expression pattern in rat testis was detected by Western blotting, while both of immunofluorescence and Western blotting were used to localize the expression of Slc26a3 in mouse sperms. The potential change of Slc26a3 expression in CFTR (cystic fibrosis transmembrane conductance regulator) knockout mice and CFTR mutant mice was also detected with Western blotting.

RESULTSThe expression level of Slc26a3 gradually decreased along epididymis from its caput to corpus, then to its cauda part. This gradually decreasing expression pattern was also found in rat testis during development. Slc26a3 was localized mainly on the trunk of mouse sperm tail. In the testis and epididymis of CFTR knockout mice and CFTR mutant mice, no significant change of Slc26a3 expression was found.

CONCLUSIONSlc26a3 is expressed in male reproductive tract, and its expression pattern is related to the function. Thus, the subfertility observed in CLD disease may be related to the important role of SLC26A3 in acid-base regulation of epididymis.

Animals ; Antiporters ; genetics ; metabolism ; Blotting, Western ; Cystic Fibrosis Transmembrane Conductance Regulator ; genetics ; metabolism ; Diarrhea ; congenital ; genetics ; metabolism ; Epididymis ; growth & development ; metabolism ; Immunohistochemistry ; Male ; Metabolism, Inborn Errors ; genetics ; metabolism ; Mice, Inbred CFTR ; Mice, Inbred ICR ; Mice, Knockout ; Rats, Sprague-Dawley ; Spermatozoa ; metabolism ; Testis ; growth & development ; metabolism