{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T05:52:22Z","timestamp":1771048342474,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2020,11,2]],"date-time":"2020-11-02T00:00:00Z","timestamp":1604275200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Peutz\u2013Jeghers Syndrome (PJS) is an autosomal dominant pre-cancerous disorder caused in 80\u201390% of cases by germline mutations in the tumor suppressor gene STK11. We performed a genetic test of the STK11 gene in two Italian young sisters suspected of PJS, since they showed pathognomonic caf\u00e9 au lait spots in absence of other symptoms and familiarity. Sequencing of all exons of STK11 gene and other 8 genes, suggested to be involved in hamartomatous syndromes, (PTEN, BMPR1A, SDHB, SDHD, SMAD4, AKT1, ENG, PIK3CA) led to the identification in both the probands of a novel germline silent mutation named c.597 G&gt;A, hitting the last nucleotide of exon 4. Interestingly, genetic testing of the two probands\u2019 parents showed that their unaffected father was carrier of this mutation. Moreover, he carried a second intronic substitution named c.465-51 T&gt;C (rs2075606) which was not inherited by his daughters. We also observed that all the family members carrying the c.597 G&gt;A mutation presented an aberrant splice variant of STK11 mRNA lacking exon 4. Furthermore, in silico analysis of c.465-51 T&gt;C substitution showed that it may activate an Enhancer Splicing Element. Finally, qRT-PCR analysis of STK11 expression levels showed a slight downregulation of the wild type allele in the father and a 2-fold downregulation in the probands compared to the unaffected mother. Our results have led the hypothesis that the c.465-51 T&gt;C intronic variant, which segregates with the wild type allele, could increase the splicing effectiveness of STK11 wild-type allele and compensate the side effect of the c.597 G&gt;A splicing mutation, being responsible for the phenotypic variability observed within this family. This finding highlight the importance of RNA analysis in genetic testing, remarking that silent DNA variant can often be splicing variant involved in disease onset and progression. The identification of these variants has a crucial role to ensure an appropriate follow-up and cancer prevention in at-risk individuals.<\/jats:p>","DOI":"10.3390\/ijms21218201","type":"journal-article","created":{"date-parts":[[2020,11,2]],"date-time":"2020-11-02T09:04:46Z","timestamp":1604307886000},"page":"8201","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Implications of Splicing Alterations in the Onset and Phenotypic Variability of a Family with Subclinical Manifestation of Peutz\u2013Jeghers Syndrome: Bioinformatic and Molecular Evidence"],"prefix":"10.3390","volume":"21","author":[{"given":"Andrea","family":"Cerasuolo","sequence":"first","affiliation":[{"name":"Molecular Biology and Viral Oncology Unit, Istituto Nazionale Tumori IRCCS \u201cFondazione G. Pascale\u201d, 80131 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesca","family":"Cammarota","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131 Naples, Italy"},{"name":"Ceinge Biotecnologie Avanzate, 80131 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesca","family":"Duraturo","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131 Naples, Italy"},{"name":"Ceinge Biotecnologie Avanzate, 80131 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Annamaria","family":"Staiano","sequence":"additional","affiliation":[{"name":"Department of Translational Medical Sciences, Section of Pediatrics, University of Naples Federico II, 80131 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2152-747X","authenticated-orcid":false,"given":"Massimo","family":"Martinelli","sequence":"additional","affiliation":[{"name":"Department of Translational Medical Sciences, Section of Pediatrics, University of Naples Federico II, 80131 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Erasmo","family":"Miele","sequence":"additional","affiliation":[{"name":"Department of Translational Medical Sciences, Section of Pediatrics, University of Naples Federico II, 80131 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paola","family":"Izzo","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131 Naples, Italy"},{"name":"Ceinge Biotecnologie Avanzate, 80131 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4752-5678","authenticated-orcid":false,"given":"Marina","family":"De Rosa","sequence":"additional","affiliation":[{"name":"Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, 80131 Naples, Italy"},{"name":"Ceinge Biotecnologie Avanzate, 80131 Naples, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Tchekmedyian, A., Amos, C.I., Bale, S.J., Zhu, D., Arold, S., Berrueta, J., Nabon, N., and McGarrity, T. (2013). Findings From the Peutz\u2013Jeghers Syndrome Registry of Uruguay. PLoS ONE.","DOI":"10.1371\/journal.pone.0079639"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1016\/j.path.2016.01.006","article-title":"Peutz\u2013Jeghers Syndrome: Pathobiology, Pathologic Manifestations, and Suggestions for Recommending Genetic Testing in Pathology Reports","volume":"9","author":"Meserve","year":"2016","journal-title":"Surg. Pathol. Clin."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1007\/s12328-019-00964-0","article-title":"Extremely Young Case of Small Bowel Intussusception Due to Peutz\u2013Jeghers Syndrome with Nonsense Mutation of STK11","volume":"12","author":"Sado","year":"2019","journal-title":"Clin. J. Gastroenterol."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Chen, H.Y., Jin, X.W., Li, B.R., Zhu, M., Li, J., Mao, G.P., Zhang, Y.F., and Ning, S.B. (2017). Cancer Risk in Patients with Peutz\u2013Jeghers Syndrome: A Retrospective Cohort Study of 336 Cases. Tumor Biol., 39.","DOI":"10.1177\/1010428317705131"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"162","DOI":"10.5152\/turkjsurg.2017.3241","article-title":"The Patients with Peutz\u2013Jeghers Syndrome Have a High Risk of Developing Cancer","volume":"3","author":"Tavusbay","year":"2018","journal-title":"Turk. J. Surg."},{"key":"ref_6","first-page":"135","article-title":"Peutz\u2013Jeghers Syndrome in Dermatology","volume":"28","author":"Nevozinskaya","year":"2019","journal-title":"Acta Dermatovenerol. Alp. Pannonica Adriat."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"38","DOI":"10.1038\/ng0198-38","article-title":"Peutz\u2013Jeghers Syndrome Is Caused by Mutations in a Novel Serine Threonine Kinase","volume":"18","author":"Jenne","year":"1998","journal-title":"Nat. Genet."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1641","DOI":"10.1086\/302159","article-title":"Loss of LKB1 Kinase Activity in Peutz\u2013Jeghers Syndrome, and Evidence for Allelic and Locus Heterogeneity","volume":"63","author":"Mehenni","year":"1998","journal-title":"Am. J. Hum. Genet."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"833","DOI":"10.1038\/sj.emboj.7600110","article-title":"LKB1 Is a Master Kinase That Activates 13 Kinases of the AMPK Subfamily, Including MARK\/PAR-1","volume":"23","author":"Lizcano","year":"2004","journal-title":"EMBO J."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1111\/j.1399-0004.2012.01928.x","article-title":"Large Deletions and Splicing-Site Mutations in the STK11 Gene in Peutz\u2013Jeghers Chilean Families","volume":"83","author":"Orellana","year":"2013","journal-title":"Clin. Genet."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1535","DOI":"10.1089\/dna.2012.1720","article-title":"One Novel Deletion and One Splicing Mutation of the LKB1 Gene in Two Chinese Patients with Peutz\u2013Jeghers Syndrome","volume":"31","author":"Chen","year":"2012","journal-title":"DNA Cell Biol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1007\/s10620-013-2875-7","article-title":"Exome Sequencing Revealed Novel Germline Mutations in Chinese Peutz\u2013Jeghers Syndrome Patients","volume":"59","author":"Wang","year":"2014","journal-title":"Dig. Dis. Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1016\/j.cancergen.2018.11.008","article-title":"STK11 Gene Analysis Reveals a Significant Number of Splice Mutations in Chinese PJS Patients","volume":"230","author":"Jiang","year":"2019","journal-title":"Cancer Genet."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Jiang, Y.L., Zhao, Z.Y., Li, B.R., Li, J., Jin, X.W., Yu, E.D., Xu, X.D., and Ning, S.B. (2019). Early Screening the Small Bowel Is Key to Protect Peutz\u2013Jeghers Syndrome Patients from Surgery: A Novel Mutation c.243delG in STK11 Gene. BMC Gastroenterol., 19.","DOI":"10.1186\/s12876-019-0987-z"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"2558","DOI":"10.1053\/j.gastro.2010.03.061","article-title":"Alu-mediated Genomic Deletion of the Serine\/Threonine Protein Kinase 11 (STK11) Gene in Peutz\u2013Jeghers Syndrome","volume":"138","author":"Galatola","year":"2010","journal-title":"Gastroenterology"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1136\/jmg.2003.010900","article-title":"Genotype-phenotype Correlations in Peutz\u2013Jeghers Syndrome","volume":"41","author":"Amos","year":"2004","journal-title":"J. Med. Genet."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"480","DOI":"10.1016\/j.asjsur.2017.08.002","article-title":"Clinical Manifestations and STK11 Germline Mutations in Taiwanese Patients with Peutz\u2013Jeghers Syndrome","volume":"41","author":"Chiang","year":"2018","journal-title":"Asian J. Surg."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1007\/s10689-017-0037-3","article-title":"An Exploration of Genotype-Phenotype Link between Peutz\u2013Jeghers Syndrome and STK11: A Review","volume":"17","author":"Daniell","year":"2018","journal-title":"Fam. Cancer"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"507","DOI":"10.3892\/etm.2016.3980","article-title":"Correlation between Genotype and Phenotype in Three Families with Peutz\u2013Jeghers Syndrome","volume":"13","author":"Zhang","year":"2017","journal-title":"Exp. Ther. Med."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"5397","DOI":"10.3748\/wjg.15.5397","article-title":"Peutz\u2013Jeghers Syndrome: Diagnostic and Therapeutic Approach","volume":"15","author":"Kopacova","year":"2009","journal-title":"World J. Gastroenterol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1353","DOI":"10.1016\/j.dld.2019.06.003","article-title":"Early Genetic Testing of STK11 Is Important for Management and Genetic Counseling for Peutz\u2013Jeghers Syndrome","volume":"51","author":"Shen","year":"2019","journal-title":"Dig. Liver Dis."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1215","DOI":"10.1093\/nar\/16.3.1215","article-title":"A Simple Salting Out Procedure for Extracting DNA from Human Nucleated Cells","volume":"16","author":"Miller","year":"1988","journal-title":"Nucleic Acids Res."},{"key":"ref_23","first-page":"2379","article-title":"Characterisation of Mesenchymal Colon Tumour-Derived Cells in Tumourspheres as a Model for Colorectal Cancer Progression","volume":"53","author":"Turano","year":"2018","journal-title":"Int. J. Oncol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"511","DOI":"10.3892\/ijmm.2015.2255","article-title":"Multivariate Analysis as a Method for Evaluating the Pathogenicity of Novel Genetic MLH1 Variants in Patients with Colorectal Cancer and Microsatellite Instability","volume":"36","author":"Duraturo","year":"2015","journal-title":"Int. J. Mol. Med."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Galatola, M., Paparo, L., Duraturo, F., Turano, M., Rossi, G.B., Izzo, P., and De Rosa, M. (2012). Beta Catenin and Cytokine Pathway Dysregulation in Patients with Manifestations of the \u201cPTEN Hamartoma Tumor Syndrome\u201d. BMC Med. Genet., 13.","DOI":"10.1186\/1471-2350-13-28"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2490","DOI":"10.1093\/hmg\/ddl171","article-title":"An Increased Specificity Score Matrix for the Prediction of SF2\/ASF-specific Exonic Splicing Enhancers","volume":"15","author":"Smith","year":"2006","journal-title":"Hum. Mol. Genet."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"3568","DOI":"10.1093\/nar\/gkg616","article-title":"ESEfinder: A Web Resource to Identify Exonic Splicing Enhancers","volume":"31","author":"Cartegni","year":"2003","journal-title":"Nucleic Acids Res."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"e67","DOI":"10.1093\/nar\/gkp215","article-title":"Human Splicing Finder: An Online Bioinformatics Tool to Predict Splicing Signals","volume":"37","author":"Desmet","year":"2009","journal-title":"Nucleic Acids Res."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"268","DOI":"10.1007\/DCR.0b013e318197d15c","article-title":"Implication of Adenomatous Polyposis Coli and MUTYH Mutations in Familial Colorectal Polyposis","volume":"52","author":"Galatola","year":"2009","journal-title":"Dis. Colon Rectum"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"e107","DOI":"10.1158\/1078-0432.CCR-17-0790","article-title":"Cancer Screening Recommendations and Clinical Management of Inherited Gastrointestinal Cancer Syndromes in Childhood","volume":"23","author":"Achatz","year":"2017","journal-title":"Clin. Cancer Res."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"170","DOI":"10.1053\/j.semdp.2018.01.004","article-title":"Hereditary Gastrointestinal Carcinomas and Their Precursors: An Algorithm for Genetic Testing","volume":"35","author":"Spoto","year":"2018","journal-title":"Semin. Diagn. Pathol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1016\/j.celrep.2018.03.052","article-title":"Systematic Analysis of Splice-Site-Creating Mutations in Cancer","volume":"23","author":"Jayasinghe","year":"2018","journal-title":"Cell Rep."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1007\/s13353-018-0444-7","article-title":"Splicing Mutations in Human Genetic Disorders: Examples, Detection, and Confirmation","volume":"59","author":"Abramowicz","year":"2018","journal-title":"J. Appl. Genet."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"655","DOI":"10.1038\/nrm.2017.86","article-title":"Mechanistic Insights into Precursor Messenger RNA Splicing by the Spliceosome","volume":"18","author":"Shi","year":"2017","journal-title":"Nat. Rev. Mol. Cell Biol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"291","DOI":"10.1146\/annurev-biochem-060614-034316","article-title":"Mechanisms and Regulation of Alternative Pre-mRNA Splicing","volume":"84","author":"Lee","year":"2015","journal-title":"Annu. Rev. Biochem."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"152","DOI":"10.3892\/br.2014.407","article-title":"Mechanism of Alternative Splicing and Its Regulation","volume":"3","author":"Wang","year":"2015","journal-title":"Biomed. Rep."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"329","DOI":"10.1016\/j.ygeno.2005.05.011","article-title":"Distribution of Exonic Splicing Enhancer Elements in Human Genes","volume":"3","author":"Wu","year":"2005","journal-title":"Genomics"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Papp, J., Kovacs, M.E., Solyom, S., Kasler, M., B\u00f8rresen-Dale, A.L., and Olah, E. (2010). High Prevalence of Germline STK11 Mutations in Hungarian Peutz\u2013Jeghers Syndrome Patients. BMC Med. Genet., 11.","DOI":"10.1186\/1471-2350-11-169"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"492","DOI":"10.1007\/s00535-008-2185-6","article-title":"Molecular Insights Into Peutz\u2013Jeghers Syndrome: Two Probands with a Germline Mutation of LKB1","volume":"43","author":"Hosogi","year":"2008","journal-title":"J. Gastroenterol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1002\/humu.1211","article-title":"Mutation Screening at the RNA Level of the STK11\/LKB1 Gene in Peutz\u2013Jeghers Syndrome Reveals Complex Splicing Abnormalities and a Novel mRNA Isoform (STK11 c.597(insertion mark)598insIVS4)","volume":"18","author":"Abed","year":"2001","journal-title":"Hum. Mutat."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1002\/humu.9046","article-title":"Two Novel Mutations and a New STK11\/LKB1 Gene Isoform in Peutz\u2013Jeghers Patients","volume":"20","author":"Resta","year":"2002","journal-title":"Hum. Mutat."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/21\/21\/8201\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:28:11Z","timestamp":1760178491000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/21\/21\/8201"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,11,2]]},"references-count":41,"journal-issue":{"issue":"21","published-online":{"date-parts":[[2020,11]]}},"alternative-id":["ijms21218201"],"URL":"https:\/\/doi.org\/10.3390\/ijms21218201","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,11,2]]}}}