Gastric neuroendocrine tumors in a BRCA2 germline mutation carrier:A case report

BACKGROUND The molecular changes present in gastric neuroendocrine tumors(NETs)include a loss of heterozygosity or mutation of MEN1,CDKN1B gene mutation,P27 heterozygous mutation,and ATP4A gene missense mutation.We identified and are the first to report a case of type 1 histamine-producing enterochromaffin-like cell NETs(ECL-cell NETs)with a BRCA2 gene germline mutation.CASE SUMMARY The patient had a history of iron-deficient anemia for 5 years,and gastroscopic examination indicated multiple gastric tumors.Then,the patient underwent distal gastrectomy.Microscopically,multifocal tumor cells were found in the mucosa and submucosa;tumor cells were organoid and arranged in nests and cords,and the stroma was rich in sinusoids.The surrounding gastric mucosa showed atrophy with mild intestinal metaplasia or pseudopyloric gland metaplasia.Neuroendocrine cells could be seen with diffuse linear,nodular,and adenomatous hyperplasia.Immunohistochemically,the tumor cells diffusely expressed cytokeratin,chromogranin,synaptophysin,and CD56.Whole-genome highthroughput molecular sequencing revealed a pathogenic germline mutation in the BRCA2 gene,a heterozygous germline frameshift mutation in exon 11,c.6443_6444del(p.S2148Yfs*2).The final diagnosis was gastric type 1 ECL-cell NETs with a BRCA2 gene germline mutation,accompanied by autoimmune gastritis.CONCLUSION This is the first report of a case of type 1 gastric ECL-cell NETs with a pathogenic germline mutation of the BRCA2 gene.The findings of this report will expand the germline mutation spectrum of gastric NETs and increase the understanding of the molecular changes present in these tumors for their improved diagnosis in the future.

Detection of germline mutations of hMLH1 and hMSH2 based on cDNA sequencing in China

AIM： TO detect the germline mutations Of hMLH1 and hMSH2 based on mRNA sequencing to identify hereditary non polyposis oolorectal cancer （HNPCC） families. METHODS： Total RNA was extracted from peripberal blood of 14 members from 12 different families fulfilling Amsterdam criteria II. mRNA of hMLH1 and hMSH2 was reversed with special primers and heat-resistant reverse tmnscriptase, cDNA was amplified with expand long template PCR and cDNA sequendng analysis was followed. RESULT： Seven germline mutations were found in 6 families （6/12, 50%）, in 4 hMLH1 and 3 hMSH2 mutations （4/12, 33.3%）; （3/12, 25%）. The mutation types involved 4 missense, 1 silent and 1 frame shift mutations as well as 1 mutation in the non-coding area. Four out of the seven mutations have not been reported previously. The 4 hMLH1 mutations were distributed in exons 8, 12, 16, and 19. The 3 hMSH2 mutations were distributed in exons 1 and 2. Six out of the 7 mutations were pathological, which were dislTibuted in 5 HNPCC families. CONCLUSION： Germline mutations of hMLH1 and hMSH2 can be found based on cDNA sequencing so as to identify HNPCC family, which is highly sensitive and has the advantages of cost and time saving.

Germline mutation analysis of MLH1 and MSH2 in Malaysian Lynch syndrome patients

AIM: To investigate the protein expression profi le of mismatch repair (MMR) genes in suspected cases of Lynch syndrome and to characterize the associated germline mutations. METHODS: Immunohistochemical analysis of tumor samples was performed to determine the protein expression profile of MMR protein. Germline mutation screening was carried out on peripheral blood samples. The entire exon regions of MLH1 and MSH2 geneswere amplifi ed by polymerase chain reaction, screened by denaturing high performance liquid chromatography (dHPLC) and analyzed by DNA sequencing to characterize the germline mutations. RESULTS: Three out of 34 tissue samples (8.8%) and four out of 34 tissue samples (11.8%) showed loss of nuclear staining by immunohistochemistry, indicating the absence of MLH1 and MSH2 protein expression in carcinoma cells, respectively. dHPLC analysis followed by DNA sequencing showed these samples to have germline mutations of MSH2 gene. However, no deleterious mutations were identifi ed in any of the 19 exons or coding regions of MLH1 gene, but we were able to identify MLH1 promoter polymorphism, -93G > A (rs1800734), in 21 out of 34 patients (61.8%). We identified one novel mutation, transversion mutation c.2005G > C, which resulted in a missense mutation (Gly669Arg), a transversion mutation in exon 1, c.142G > T, which resulted in a nonsense mutation (Glu48Stop) and splice-site mutation, c.2006-6T > C, which was adjacent to exon 13 of MSH2 gene. CONCLUSION: Germline mutations were identified in four Malaysian Lynch syndrome patients. Immunohistochemical analysis of tumor tissue proved to be a good pre-screening test before proceeding to germline mutation analysis of DNA MMR genes.

Imatinib response of gastrointestinal stromal tumor patients with germline mutation on KIT exon 13:A family report

Familial gastrointestinal stromal tumor(GIST) is a rare autosomal dominant disorder associated with mutations in the KIT gene in the majority of cases. Although, exon 11 appears to be the hot spot region for approximately 95% of germline mutations, pathogenic variations have also been identified in exon 8, 13 and 17. Exon 13 germline mutations are extremely rare amongst familial GISTs and seven families with a germline mutation have been reported to date. Moreover, the role of imatinib mesylate in this rare familiar settings is not completely known so far. We describe here clinical, imaging, pathological and genetic findings of a family with four affected members; grandmother, his son and two grand-sons having a germline gain-of-function mutation of KIT in exon 13 and discuss the imatinib mesylate treatment surveillance outcomes towards disease management.

Two novel germline mutations of MLH1 and investigation of their pathobiology in hereditary non-polyposis colorectal cancer families in China

AIM： To detect germline mutations of MLH1, and investigate microsatellite instability and expression of MLH1 in tumor tissues of hereditary non-polyposis colorectal cancer （HNPCC） with two novel germline mutations, and further investigate the pathobiology of the two novel mutations of MLH1. METHODS： RNA was extracted from the peripheral blood of 12 patients from 12 different families that fulfilled the Amsterdam 11 Criteria for HNPCC. Germline mutations of MLH1 were determined by RT-PCR, followed by cDNA sequencing analysis. PCR-GeneScan analysis was used to investigate microsatellite instability with a panel of five microsatellite markers （BAT26, BAT25, D5S346, D2S123 and mfd15）, along with immunohistochemical staining to detect the expression of MLH1 protein in two patients＇ tumor tissues with novel mutations. RESULTS： Three germline mutations were found in four patients, one of the mutations has previously been reported, but the other two, CGC→TGC at codon 217 of exon 8 and CCG→CTG at codon 581 of exon 16, have not been reported. The two patients＇ tumor tissues with novel mutations had high-frequency microsatellite instability that showed more than two unstable loci, and both tumors lost their MLH1 protein expression. CONCLUSION： The two novel germline mutations of MLH1 in HNPCC families i.e. CGC→TGC at codon 217 of exon 8 and CCG→CTG at codon 581 of exon 16, are very likely to have pathological significance.

Germline mutations in hereditary diffuse gastric cancer

Gastric cancer is one of the leading causes of cancer-related deaths worldwide. Among which, about 1%–3% of gastric cancer patients were characterized by inherited gastric cancer predisposition syndromes, knowing as hereditary diffuse gastric cancer（HDGC）. Studies reported that CDH1 germline mutations are the main cause of HDGC. With the help of rapid development of genetic testing technologies and data analysis tools, more and more researchers focus on seeking candidate susceptibility genes for hereditary cancer syndromes. In addition, National Comprehensive Cancer Network（NCCN） guidelines recommend that the patients of HDGC carrying CDH1 mutations should undergo prophylactic gastrectomy or routine endoscopic surveillances. Therefore, genetic counseling plays a key role in helping individuals with pathogenic mutations make appropriate risk management plans. Moreover, experienced and professional genetic counselors as well as a systematic multidisciplinary team（MDT） are also required to facilitate the development of genetic counseling and benefit pathogenic mutation carriers who are in need of regular and standardized risk management solutions. In this review, we provided an overview about the germline mutations of several genes identified in HDGC, suggesting that these genes may potentially act as susceptibility genes for this malignant cancer syndrome. Furthermore, we introduced information for prevention, diagnosis and risk management of HDGC. Investigations on key factors that may have effect on risk management decision-making and genetic data collection of more cancer syndrome family pedigrees are required for the development of HDGC therapeutic strategies.

First report of a de novo germline mutation in the MLH1 gene

Hereditary non-polyposis colorectal carcinoma （HNPCC） is an autosomal dominant disorder associated with colorectal and endometrial cancer and a range of other tumor types. Germline mutations in the DNA mismatch repair （MMR） genes, particularly MLH1, MEH2, and MEH5, underlie this disorder. The vast majority of these HNPCC-associated mutations have been proven, or assumed, given the family history of cancer, to be transmitted through several generations. To the best of our knowledge, only a single case of a de novo germline MMR gene mutation （in MEH2） has been reported till now. Here, we report a patient with a de novo mutation in MLH1. We identified a MLH1 Q701X truncating mutation in the blood lymphocytes of a male who had been diagnosed with rectal cancer at the age of 35. His family history of cancer was negative for the first- and second-degree relatives. The mutation could not be detected in the patient＇s parents and sibling and paternity was confirmed with a set of highly polymorphic markers. Non-penetrance and small family size is the common explanation of verified negative family histories of cancer in patients with a germline MMR gene mutation. However, in addition to some cases explained by non-paternity, de novo germline mutations should be considered as a possible explanation as well. As guidelines that stress not to restrict MMR gene mutation testing to patients with a positive family history are more widely introduced, more cases of de novo MMR gene germline mutations may be revealed.

Clinicopathological features of typical and nontypical hereditary non-polyposis colorectal cancer and their germline mutation of hMLH_1 and hMSH_2

Objective To study the clinicopathological features of the Chinese hereditary non-polyposis colorectal cancer and its germline mutation of hMLH1 and hMSH2. Methods Thirteen typical Chinese hereditary non-polyposis colorectal carcinoma (HNPC) C kindreds and 19 nontypical HNPCC families were registered and followed up. The germline mutation of the hMLH1 and hMSH2 of 12 index cases of 6 typical and 6 nontypical NHPCC were screened by PCR-SSCP. Samples with abnormal mobility were sequenced direcdy. Results The average age of typical HNPCC was 47, no difference existed between sexs. Location of the tumors of typical HNPCC represented 44.7% on the right half colon and non-typical HNPCC 65. 8% on the rectum. The rate of the metachronos cancer was 11.5%. The 3 - , 5 - and 10 -year survival rate was 64. 0%, 45. 3% and 31. 2% respectively. Among 12 cases, 8 showed abnormal mobility. Except for an intron polymorphinism, six exons abnormalities were found in 5 of 12 proband. Sequencing showed 4 missense,7

Familial gastrointestinal stromal tumors with KIT germline mutation in a Chinese family:A case report

BACKGROUND Familial gastrointestinal stromal tumors(GISTs)is a rare autosomal dominant disorder characterized by an array of clinical manifestations.Only 35 kindreds with germline KIT mutations and six with germline PDGFRA mutations have been reported so far.It is often characterized by a series of manifestations,such as multiple lesions and hyperpigmentation.However,the effect of imatinib treatment in these patients is still uncertain.CASE SUMMARY Here,we report two patients(father and daughter)in a Chinese family(for the first time)with germline KIT mutation,and described their pathology,genetics and clinical manifestations.A 25-year-old Chinese woman went to hospital because of abdominal pain,and computed tomography showed multiple tumors in the small intestine.Small pigmented spots appeared on the skin within a few months after birth.Her father also had multiple pigmented spots and a history of multifocal GISTs.Multiple GISTs associated with diffuse interstitial Cajal cells(ICCs)hyperplasia were positive for CD117 and DOG-1.Gene sequencing revealed a germline mutation at codon 560 of exon 11(p.V560G)of KIT gene in these two patients.Imatinib therapy showed the long-lasting disease stability after resection.Remarkably,the hypopigmentation of the skin could also be observed.Luckily germline KIT mutation has not been identified yet in the 3-year-old daughter of the female patient.CONCLUSION Diagnosis of familial GISTs depends on combination of diffuse ICCs hyperplasia,germline KIT/PDGFRA mutation,hyperpigmentation and family history.

Identification of Germline Mutations in East‑Asian Young Never‑Smokers with Lung Adenocarcinoma by Whole‑Exome Sequencing

Recently,an increasing number of young never-smokers are diagnosed with lung cancer.The aim of this study is to investigate the genetic predisposition of lung cancer in these patients and discover candidate pathogenic variants for lung adenocarcinoma in young never-smokers.Peripheral blood was collected from 123 never-smoking east-Asian patients diagnosed with lung adenocarcinoma before the age of 40.Whole-exome sequencing(WES)was conducted on genomic DNA extracted from peripheral blood cells.As a result,3,481 single nucleotide variants were identified.By bioinformatical tools and the published gene list associated with genetic predisposition of cancer,pathogenic variants were detected in ten germline genes:ATR,FANCD2,FANCE,GATA2,HFE,MSH2,PDGFRA,PMS2,SDHB,and WAS.Patients with pathogenic variants were more likely to occur in females(9/10,90.0%)and have stage IV lung adenocarcinoma(4/10,40%).Furthermore,germline muta-tions in 17 genes(ASB18,B3GALT5,CLEC4F,COL6A6,CYP4B1,C6orf132,EXO1,GATA4,HCK,KCP,NPHP4,PIGX,PPIL2,PPP1R3G,RRBP1,SALL4,and TTC28),which occurred in at least two patients,displayed potentially pathogenic effects.Gene ontology analysis further showed that these genes with germline mutations were mainly located in nucleo-plasm and associated with DNA repair-related biological processes.The study provides spectrum of pathogenic variants and functional explanation for genetic predisposition of lung adenocarcinoma in young never-smokers,which sheds a light on prevention and early diagnosis of lung cancer.

A new era of mutation rate analyses: Concepts and methods

The mutation rate is a pivotal biological characteristic,intricately governed by natural selection and historically garnering considerable attention.Recent advances in high-throughput sequencing and analytical methodologies have profoundly transformed our understanding in this domain,ushering in an unprecedented era of mutation rate research.This paper aims to provide a comprehensive overview of the key concepts and methodologies frequently employed in the study of mutation rates.It examines various types of mutations,explores the evolutionary dynamics and associated theories,and synthesizes both classical and contemporary hypotheses.Furthermore,this review comprehensively explores recent advances in understanding germline and somatic mutations in animals and offers an overview of experimental methodologies,mutational patterns,molecular mechanisms,and driving forces influencing variations in mutation rates across species and tissues.Finally,it proposes several potential research directions and pressing questions for future investigations.

Germline MLH1 and MSH2 mutational spectrum including frequent large genomic aberrations in Hungarian hereditary non-polyposis colorectal cancer families:Implications for genetic testing

AIM: To analyze the prevalence of germline MLH1 and MSH2 gene mutations and evaluate the clinical characteristics of Hungarian hereditary non-polyposis colorectal cancer (HNPCC) families. METHODS: Thirty-six kindreds were tested for mutations using conformation sensitive gel electrophoreses, direct sequencing and also screening for genomic rearrangements applying multiplex ligation-dependent probe amplifi cation (MLPA). RESULTS: Eighteen germline mutations (50%) were identifi ed, 9 in MLH1 and 9 in MSH2. Sixteen of these sequence alterations were considered pathogenic, the remaining two were non-conservative missense alterations occurring at highly conserved functional motifs. The majority of the defi nite pathogenic mutations (81%, 13/16) were found in families fulfilling the stringent Amsterdam Ⅰ/Ⅱ criteria, including three rearrangements revealed by MLPA (two in MSH2 and one in MLH1). However, in three out of sixteen HNPCC-suspected families (19%), a disease-causing alteration could be revealed. Furthermore, nine mutations described here are novel, and none of the sequence changes were found in more than one family.CONCLUSION: Our study describes for the f irst time the prevalence and spectrum of germline mismatch repair gene mutations in Hungarian HNPCC and suspected-HNPCC families. The results presented here suggest that clinical selection criteria should be relaxed and detection of genomic rearrangements should be included in genetic screening in this population.

Identification of a novel germline missense mutation of the androgen receptor in African American men with familial prostate cancer

Race, family history and age are the unequivocally accepted risk factors for prostate cancer （PCa）. Androgen receptor （AR）-dependent signaling is an important element in prostate carcinogenesis and its progression to metastatic disease. We examined the possibility of genomic changes in the AR in association with familial PCa in African Americans who have a higher incidence and mortality rate and a clinically more aggressive disease presentation than Caucasians. Genomic DNAs of 60 patients from 30 high-risk African American and Caucasian families participating in the Louisiana State University Health Sciences Center genetic linkage study of PCa were studied. Exon-specific polymerase-chain reaction, bi-directional automated sequencing and restriction enzyme genotyping were used to analyze for mutations in the coding region of the AR gene. We identified a germline AR （A1675T） （T559S） substitution mutation in the DNA-binding domain in three PCa-affected members of an African- American family with a history of early-onset disease. The present study describes the first AR germline mutation in an African-American family with a history of familial PCa. The AR （T559S） mutation may contribute to the disease by altering AR DNA-binding affinity and/or its response to androgens, non-androgenic steroids or anti-androgens. Additional studies will be required to define the frequency and contribution of the AR （A 1675T） allele to early-onset and/or familial PCa in African Americans.

Germline mutational profile of Chinese patients under 70 years old with colorectal cancer

Background:Inherited susceptibility accounts for nearly one-third of colorectal cancer(CRC)predispositions and has an 80%-100%lifetime risk of this disease.However,there are few data about germline mutations of hereditary CRC-related genes in Chinese patients with CRC.This study aimed to assess the prevalence of gene mutations related to cancer susceptibility among Chinese patients with CRC,differences between Chinese and Western patients,and the phenotypegenotype correlation.Methods:We retrospectively collected tumor samples from 526 patients with CRC under 70 years old who underwent hereditary CRC genetic testing.A series of bioinformatic analyses,as well as statistical comparisons,were performed.Results:We found that 77 patients(14.6%)harbored functional variants of the 12 genes.The mutation frequencies of the top 5 mutated genes were 6.5%for MutL homolog 1(MLH1),5.1%for MutS homolog 2(MSH2),1.0%for MSH6,0.8%for PMS1 homolog 2(PMS2),and 0.8%for APC regulator of the WNT signaling pathway(APC).Our data showed much higher rates of mutations of MSH6 and PMS2 genes among all mismatch repair(MMR)genes as compared with those in Western populations.Mutations in MLH1,MSH2,and MSH6 were found to be mutually exclusive.Patients with MLH1 or MSH2 mutations had higher frequencies of personal history of cancer(MLH1:20.6%vs.8.7%;MSH2:25.9%vs.8.6%)and family history of cancer than those without these mutations(MLH1:73.5%vs.48.4%;MSH2:70.4%vs.48.9%),and the lesions were more prone to occur on the right side of the colon than on the left side(MLH1:73.5%vs.29.3%;MSH2:56.0%vs.31.0%).The proportion of stage I/II disease was higher in patients with MLH1 mutations than in those without MLH1 mutations(70.6%vs.50.7%),and the rate of polyps was higher in patients withAPC mutations than in those with wild-type APC(75.0%vs.17.4%).Conclusion:These results provide a full-scale landscape of hereditary susceptibility over 12 related genes in CRC patients and suggest that a comprehensive multi-gene panel testing for hereditary CRC predisposition could be a helpful analysis in clinical practice.

Absence of MutY homologue mutation in patients with multiple sporadic adenomatous polyps in Korea

AIM： Recently, germ-line mutation in the base excision repair gene MYH has been identified to cause a novel autosomal recessive form of familial adenomatous polyposis （FAP）. Interestingly, a striking evidence for MYH mutations within different ethnic groups has been demonstrated. In this study, we screened 30 patients with multiple adenomatous polyps for MYH mutations to assess its prevalence and ethnic specificity in Korea. METHODS： Thirty patients （21 men and 9 women; mean age 62.3 years） with multiple adenomatous polyps were examined for MYH mutations. The mean number of adenomas per patient was 10.0. Sixteen exonic regions and their intronic sequences were amplified by PCR and subjected to SSCP and DNA sequencing analyses. RESULTS： None of the patients was identified to carry any truncating or sequence alterations in MYH. Our screening for the mutational regions, which were recognized from Caucasian patients or affected Indian families, also failed to detect sequence substitutions. CONCLUSION： Mutation in MYHmay be rarely involved in the pathogenesis of multiple sporadic colorectal adenomas in Korean population, although a large-scale analysis will be required to clarify the presence of specific MYH variants in a subset of patients and their role in the predisposition of multiple colorectal adenomas in Korean population.

Identification of novel Lynch syndrome mutations in Chinese patients with endometriod endometrial cancer

Objective:Lynch syndrome(LS)predisposes patients to early onset endometrioid endometrial cancer(EEC).However,little is known about LS-related EEC in the Chinese population.The aim of this study was to investigate the prevalence of LS and to identify the specific variants of LS in Chinese patients with EEC.Methods:We applied universal immunohistochemistry screening to detect the expression of mismatch repair(MMR)proteins,which was followed by MLH1 methylation analysis to identify suspected LS cases,next-generation sequencing(NGS)to confirm LS,and microsatellite instability(MSI)analysis to verify LS.Results:We collected 211 samples with EEC.Twenty-seven(27/211,12.8%)EEC cases had a loss of MMR protein expression.After MLH1 methylation analysis,16 EEC cases were suggested to be associated with LS.Finally,through NGS and MSI analysis,we determined that 10 EEC(10/209,4.78%)cases were associated with LS.Among those cases,3 unreported mutations(1 frameshift and 2 nonsense)were identified.M SH6 c.597_597delC,found in 4 patients,is likely to be a founder mutation in China.Conclusions:We demonstrated the feasibility of a process for LS screening in Chinese patients with EEC,by using universal immunohistochemistry screening followed by MLH1 methylation analysis and confirmation through NGS and MSI analysis.The novel mutations identified in this study expand knowledge of LS.

Specific intronic p53 mutation in esophageal squamous cell carcinoma in Southern Thailand

AIM:To investigate p53 mutations in esophageal cancer in a high-risk population,and correlate them with smoking,alcohol consumption and betel chewing.METHODS:One hundred and sixty-five tumor samples of esophageal squamous cell carcinoma(ESCC) obtained from a university hospital in Songkhla province,Southern Thailand were investigated for p53 mutations in exons 5-8,using polymerase chain reaction-single strand conformation polymorphism analysis,followed by direct sequencing.A polymerase chain reactionrestriction fragment length polymorphism(RFLP) assay was additionally used to confirm possible germline mutation in intron 6.A history of risk habits was obtained by interviews.The association between risk habits and mutation frequency was evaluated using the χ 2 test.RESULTS:The studied specimens were from 139 male and 26 female patients with ESCC,treated at Songklanagarind Hospital.Most of the patients were smokers(86.7%) and alcohol consumers(72.73%),and 38.3% were betel chewers.Forty-three mutations of the p53 gene were detected in 25.5%(42/165) of tumor samples.Mutations were most commonly found in exon 5(25.6%) and exon 8(25.6%).Mutations in the hot-spot codon 248 were found in four cases(9.3% of all mutations).G:C→C:G(30.23%),G:C→A:T(27.90%) and G:C →T:A(16.28%) were the prevalent spectra of mutations.Unexpectedly,among 10 intronic mutations,eight cases harbored a similar mutation:G→C substitution in intron 6(nucleotide 12759,GenBank NC_000017).These were additionally confirmed by the RFLP technique.Similar mutations were also detected in their matched blood samples using RFLP and direct sequencing,which suggested germline mutations.There was no significant correlation between risk habits and p53 mutation frequency.CONCLUSION:A proportion of Thai ESCC patients harbored specific intronic p53 mutations,which might be germline mutations.Further studies are needed to explore this novel finding.

Novel TINF2 gene mutation in dyskeratosis congenita with extremely short telomeres:A case report

BACKGROUND Dyskeratosis congenita is a rare disease characterized by bone marrow failure and a clinical triad of oral leukoplakia,nail dystrophy,and abnormal skin pigmentation.The genetics of dyskeratosis congenita include mutations in genes involved in telomere maintenance,including TINF2.CASE SUMMARY Here,we report a female patient who presented thrombocytopenia,anemia,reticulate hyperpigmentation,dystrophy in fingernails and toenails,and leukoplakia on the tongue.A histopathological study of the skin showed dyskeratocytes;however,a bone marrow biopsy revealed normal cell morphology.The patient was diagnosed with dyskeratosis congenita,but her family history did not reveal significant antecedents.Whole-exome sequencing showed a novel heterozygous punctual mutation in exon 6 from the TINF2 gene,namely,NM_001099274.1:-c.854delp.(Val285-Alafs*32).An analysis of telomere length showed short telomeres relative to the patient’s age.CONCLUSION The disease in this patient was caused by a germline novel mutation of TINF2 in one of her parents.

Inherited Genetic Susceptibility to Nonimmunosuppressed Epstein-Barr Virus-associated T/NK-cell Lymphoproliferative Diseases in Chinese Patients

Epstein-Barr virus(EBV)T/NK-cell lymphoproliferative diseases are characterized by clonal expansion of EBV-infected T or NK cells,including chronic active EBV infection of T/NK-cell type(CAEBVT/NK),EBV-associated hemophagocytic lymphohistiocytosis(EBV HLH),extranodal NK/T-cell lymphoma of nasal type(ENKTL),and aggressive NK-cell leukemia(ANKL).However,the role of inherited genetic variants to EBV+T/NK-LPDs susceptibility is still unknown.A total of 171 nonimmunosuppressed patients with EBV T/NK-LPDs and 104 healthy donors were retrospectively collected and a targeted sequencing study covering 15 genes associated with lymphocyte cytotoxicity was performed.The 94 gene variants,mostly located in UNCI 3D,LYST,ITK,and PRF1 genes were detected,and mutations covered 28/50(56.00%)of CAEBV-T/NK,31/51(60.78%)of EBV HLH,13/28(46.42%)of ENKTL,and 13/48(27.09%)of ANKL.Most mutations represented monoallelic and missense.Three-year overall survival rate of patients with CAEBV-T/NK and EBV+HLH was significantly lower in patients with germline mutations than in those without germline mutations(P=0.0284,P=0.0137).Our study provided novel insights into understanding a spectrum of nonimmunosuppressed EBV*T/NK-LPDs with respect to genetic defects associated with lymphocyte cytotoxicity and reminded us that the gene sequencing may be an auxiliary test for diagnosis and risk stratification of EBV+T/NK-LPDs.

A rare occurrence of a hereditary Birt-Hogg-Dubésyndrome:A case report

BACKGROUND Birt-Hogg-Dubé(BHD)syndrome is a rare autosomal dominant disease caused by germline mutations in the folliculin(FLCN)protein gene,which usually manifests as cutaneous fibrofolliculoma,pulmonary cysts,renal cell carcinoma,and spontaneous pneumothorax.CASE SUMMARY A 26-year-old woman with no history of smoking was admitted to the Respiratory Department of our hospital due to intermittent wheezing that lasted for 8 mo.She had experienced recurrent spontaneous pneumothorax more than four times during the past 8 mo.After admission,the patient again suffered from left pneumothorax without a clear reason.Lung computed tomography(CT)showed multiple low-density cystic changes in both lungs.Physical examination on admission revealed multiple white dome-shaped papules in the neck,the nape,and behind the ear.In addition,the patient had a family history of spontaneous pneumothorax.Her mother had suffered from pneumothorax four times(at age 36,37,42,and 50 years).Her second maternal aunt had suffered from a right pneumothorax at the age of 40.The multidisciplinary diagnosis of BHD,which included the Respiratory Department,Radiology Department,Pathology Department,and Dermatological Department,was BHD and was later confirmed by family genetic testing.The same variation(FLCN gene)was found in the patient’s mother and aunt.CONCLUSION This case highlights the importance of multidisciplinary diagnosis and a treatment platform for the diagnosis of BHD.