Familial Melanoma Phenotype With Xeroderma Pigmentosum Group C (XP-C) Genotype - The Putative Role of MC1R Polymorphism as Modifier.

INTRODUCTION: Xeroderma pigmentosum (XP), a rare inherited condition, hallmarked by extreme sensitivity to sun exposure resulting in multiple skin cancers and non-malignant skin alterations is attributed to homozygous inactivating pathogenic variants (PVs) in DNA repair genes, predominantly the XPC gene. OBJECTIVES: Report a unique phenotypic expression of mutant XPC allele that may be compatible with a putative modifier role for MC1R polymorphism. METHODS: A family of 13 siblings, seven of whom were diagnosed with at least one cutaneous melanoma (N = 53) and non-melanoma skin cancers (N = 9) was studied. Of seven melanoma-affected cases, five consented for genetic analysis. CDKN2A revealed no PV in any case and subsequent whole-exome sequencing (WES) identified a rare homozygous missense PV (c.919C>T; p.Arg307Trp) in exon 8 of the XPC gene in all affected individuals. Notably, XPC PV carriers who co-harbored the p.I155T MC1R variant (N = 3) exhibited larger number of tumors, deeper Breslow indexes, higher rates of invasive melanomas and earlier age at diagnosis compared with non MC1R variant carriers (N = 2). CONCLUSIONS: Familial malignant melanoma phenotype may, in fact, be an unusual clinical presentation of XPC, and MC1R may be a genetic modifier of penetrance and phenotype of mutant XPC alleles.

Bilateral Peters' anomaly, aniridia and Wilms tumour (WAGR syndrome) in monozygotic twins.

AIM: This study reports the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins subsequently diagnosed with Wilms tumour (WAGR syndrome). METHODS: Two monozygotic female twins were referred at age 2 months with bilateral corneal opacity. A diagnosis of Peters' anomaly associated to aniridia was made in both eyes of both twins. Physical examination and ultrasonography were carried out at 12 months of age to explore the possibility of WAGR-related anomalies, specifically Wilms tumour. DNA were isolated and subjected to whole exome sequencing. RESULTS: Peters' anomaly associated to aniridia in both eyes as well as bilateral Wilms tumour in both children were diagnosed. Exome analyses showed a large heterozygous deletion encompassing 6 648 473 bp in chromosome 11p13, using Integrative Genomics Viewer and AnnotSV software. CONCLUSION: WAGR syndrome is a rare contiguous gene deletion syndrome with a greater risk of developing Wilms tumour associated with Peters' anomaly and congenital aniridia. However, co-occurrence of both anomalies was rarely reported in twins, and never in both eyes of monozygotic twins. Here, we report the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins with WAGR syndrome.

Evaluation of clinical and genetic factors in obstructive sleep apnoea.

Purpose: To evaluate the correlation between several presumed candidate genes for obstructive sleep apnoea (OSA) and clinical OSA phenotypes and propose a predictive comprehensive model for diagnosis of OSA. Methods: This case-control study compared polysomnographic patterns, clinical data, morbidities, dental factors and genetic data for polymorphisms in PER3, BDNF, NRXN3, APOE, HCRTR2, MC4R between confirmed OSA cases and ethnically matched clinically unaffected controls. A logistic regression model was developed to predict OSA using the combined data. Results: The cohort consisted of 161 OSA cases and 81 controls. Mean age of cases was 53.5 ± 14.0 years, mostly males (57%) and mean body mass index (BMI) of 27.5 ± 4.3 kg/m2. None of the genotyped markers showed a statistically significant association with OSA after adjusting for age and BMI. A predictive algorithm included the variables gender, age, snoring, hypertension, mouth breathing and number of T alleles of PER3 (rs228729) presenting 76.5% specificity and 71.6% sensitivity. Conclusions: No genetic variant tested showed a statistically significant association with OSA phenotype. Logistic regression analysis resulted in a predictive model for diagnosing OSA that, if validated by larger prospective studies, could be applied clinically to allow risk stratification for OSA.

Traboulsi syndrome without features of Marfan syndrome caused by a novel homozygous ASPH variant associated with a heterozygous FBN1 variant.

BACKGROUND: Traboulsi syndrome is a rare disease clinically characterized by facial dysmorphism, abnormal spontaneous filtering blebs, ectopia lentis (EL) and multiple anterior segment abnormalities. MATERIAL AND METHODS: An 18-year-old female was referred to the Emergency Service of Hospital São Geraldo (HSG) claiming decreased right eye (RE) visual acuity associated with ocular pain that was noticed approximately 2 months earlier. She underwent a complete ophthalmic and physical examination including hands, ankle, wrist and chest X-ray, abdominal ultrasound, echocardiogram and genetic analysis (whole-exome sequencing). RESULTS: The ophthalmic examination revealed a high myopia with spherical equivalent of - 9.50 D and best corrected visual acuity (BCVA) of 20/60 in RE and - 9.25 D with BCVA of 20/30 in the left eye (LE). Slit-lamp examination showed normal conjunctiva in both eyes (BE) and a superior-temporal cystic lesion in RE and nasal in LE; the flat anterior chamber in BE with the transparent crystalline lens touches the central corneal endothelium in the RE. Fundoscopy suggested glaucoma as the cup/disc ratio was 0.7, although the intraocular pressure (IOP) was 10 mmHg in BE without medication. Validation of data from whole exome demonstrated a novel splicing homozygous pathogenic variant (PV) (c.1765-1G>A) of the ASPH gene as well as a heterozygous variant of unknown significance (VUS) of the FBN1 gene (c.6832C>T). CONCLUSION: We here report a novel splice-affecting homozygous pathogenic variant in the ASPH gene that was detected in a Brazilian patient with clinical features of Traboulsi syndrome.

Whole-exome identifies germline variants in families with obstructive sleep apnea syndrome.

Background: Obstructive sleep apnea syndrome (OSAS) (OMIM #107650) is characterized by complete or partial obstruction of the upper airways, resulting in periods of sleep associated apnea. OSAS increases morbidity and mortality risk from cardiovascular and cerebrovascular diseases. While heritability of OSAS is estimated at ∼40%, the precise underlying genes remain elusive. Brazilian families with OSAS that follows as seemingly autosomal dominant inheritance pattern were recruited. Methods: The study included nine individuals from two Brazilian families displaying a seemingly autosomal dominant inheritance pattern of OSAS. Whole exome sequencing of germline DNA were analyzed using Mendel, MD software. Variants selected were analyzed using Varstation® with subsequent analyses that included validation by Sanger sequencing, pathogenic score assessment by ACMG criteria, co-segregation analyses (when possible) allele frequency, tissue expression patterns, pathway analyses, effect on protein folding modeling using Swiss-Model and RaptorX. Results: Two families (six affected patients and three unaffected controls) were analyzed. A comprehensive multistep analysis yielded variants in COX20 (rs946982087) (family A), PTPDC1 (rs61743388) and TMOD4 (rs141507115) (family B) that seemed to be strong candidate genes for being OSAS associated genes in these families. Conclusion: Sequence variants in COX20, PTPDC1 and TMOD4 seemingly are associated with OSAS phenotype in these families. Further studies in more, ethnically diverse families and non-familial OSAS cases are needed to better define the role of these variants as contributors to OSAS phenotype.

Selective visuoconstructional impairment following mild COVID-19 with inflammatory and neuroimaging correlation findings.

People recovered from COVID-19 may still present complications including respiratory and neurological sequelae. In other viral infections, cognitive impairment occurs due to brain damage or dysfunction caused by vascular lesions and inflammatory processes. Persistent cognitive impairment compromises daily activities and psychosocial adaptation. Some level of neurological and psychiatric consequences were expected and described in severe cases of COVID-19. However, it is debatable whether neuropsychiatric complications are related to COVID-19 or to unfoldings from a severe infection. Nevertheless, the majority of cases recorded worldwide were mild to moderate self-limited illness in non-hospitalized people. Thus, it is important to understand what are the implications of mild COVID-19, which is the largest and understudied pool of COVID-19 cases. We aimed to investigate adults at least four months after recovering from mild COVID-19, which were assessed by neuropsychological, ocular and neurological tests, immune markers assay, and by structural MRI and 18FDG-PET neuroimaging to shed light on putative brain changes and clinical correlations. In approximately one-quarter of mild-COVID-19 individuals, we detected a specific visuoconstructive deficit, which was associated with changes in molecular and structural brain imaging, and correlated with upregulation of peripheral immune markers. Our findings provide evidence of neuroinflammatory burden causing cognitive deficit, in an already large and growing fraction of the world population. While living with a multitude of mild COVID-19 cases, action is required for a more comprehensive assessment and follow-up of the cognitive impairment, allowing to better understand symptom persistence and the necessity of rehabilitation of the affected individuals.

Interrogation of TERT promoter hotspot mutations in ameloblastoma and ameloblastic carcinoma.

BACKGROUND: TERT promoter mutations increase telomerase activity, conferring cell immortality. The coexistence of TERT promoter mutations with BRAFV600E is associated with aggressiveness. Ameloblastoma and ameloblastic carcinoma are infiltrative neoplasms that harbor BRAFV600E; however, it remains unknown if these odontogenic tumors also show TERT promoter mutations. METHODS: Genomic DNA of paraffin-embedded ameloblastomas (n = 6) and ameloblastic carcinomas (n = 3) were Sanger-sequenced to assess the hotspot TERT promoter mutations C228T and C250T. BRAFV600E status was screened by TaqMan allele-specific quantitative polymerase chain reaction. RESULTS: None of the samples harbored TERT promoter mutations. The BRAFV600E mutation was positive in 3 of 6 of ameloblastomas and in 1 of 3 of ameloblastic carcinomas. CONCLUSION: The absence of TERT promoter mutation in the samples indicates that this molecular event is not relevant to the tumors' pathogenesis. Further studies are necessary to explore undefined genetic or epigenetic mechanisms related to TERT-upregulation in ameloblastoma, and the telomerase activity in ameloblastic carcinoma.

Analysis of KRAS, BRAF, and EGFR mutational status in respiratory epithelial adenomatoid hamartoma (REAH).

BACKGROUND: Respiratory epithelial adenomatoid hamartoma (REAH) is a sinonasal glandular overgrowth arising from the surface respiratory epithelium and invaginating into the stroma. Clinically, it appears as a polypoid mass that may cause nasal obstruction, anosmia, and epistaxis. The presence of cartilaginous and/or osseous areas move the lesion to a chondro-osseous respiratory epithelial (CORE) hamartoma subtype. Scattered small seromucinous glands may be observed between typical REAH glands and when it is the only feature, it represents seromucinous hamartoma (SH). The molecular pathogenesis of REAH has been poorly explored and remains unclear. Given that KRAS, BRAF, and EGFR mutations have been detected in a variety of sinonasal tumors, we aimed to assess these mutations in REAH and SH. METHODS: Ten REAH (including one CORE subtype), in addition to two SH cases, were Sanger sequenced by standard techniques. The targeted regions included KRAS exons 2-4 (encompassing hotspots codons 12, 13, 61, and 146), BRAF exons 11 and 15 (spanning the V600 codon), and EGFR exons 19 and 20. RESULTS: All REAH and SH samples showed wild-type sequences for KRAS, BRAF, and EGFR genes. CONCLUSION: Our results demonstrate a lack of KRAS, BRAF, or EGFR pathogenic variants with further evaluation of REAH and SH needed to elucidate driver genetic events.

Chronic rhinosinusitis with nasal polyps does not harbor KRAS, BRAF, and EGFR mutations.

BACKGROUND: Chronic rhinosinusitis is a chronic inflammation of the nasal mucosa and nasal polyps are present in ~25%-30% of cases (chronic rhinosinusitis with nasal polyps [CRSwNP]). CRSwNP is associated with significant morbidity and decreased quality of life, making it clinically important. Inflammation leads to DNA damage and DNA mutations occur in some inflammatory diseases. Notably, mutations in KRAS, BRAF, and EGFR have been reported in different human benign and malignant neoplastic lesions. In addition, KRAS mutations have also been reported in non-neoplastic tissues under chronic inflammatory conditions. Importantly, KRAS mutations have been reported in oncocytic sinonasal papillomas and sinonasal squamous cell carcinoma associated with oncocytic sinonasal papilloma and EGFR mutations have been reported in sinonasal adenocarcinoma, inverted sinonasal papilloma, and sinonasal squamous cell carcinoma associated with inverted sinonasal papilloma. The molecular pathogenesis of nasal polyps remains unclear. Therefore, the present study aimed to investigate the presence of KRAS, BRAF, and EGFR pathogenic mutations in CRSwNP. METHODS: Fourteen chronic rhinosinusitis-associated nasal polyp samples were direct sequenced, targeting KRAS exons 2, 3, and 4 (encompassing important hotspot mutations, including codons 12, 13, 61 and 146), BRAF exons 11 and 15, and EGFR exons 19 and 20. RESULTS: No pathogenic mutations were detected in the sequenced regions of KRAS, BRAF, and EGFR genes. CONCLUSION: This finding suggests that mutations in these genes are not a frequent event in CRSwNP, and, if they occur, they might represent marginal events at best.

Adenoid ameloblastoma harbors beta-catenin mutations.

Adenoid ameloblastoma is a very rare benign epithelial odontogenic tumor characterized microscopically by epithelium resembling conventional ameloblastoma, with additional duct-like structures, epithelial whorls, and cribriform architecture. Dentinoid deposits, clusters of clear cells, and ghost-cell keratinization may also be present. These tumors do not harbor BRAF or KRAS mutations and their molecular basis appears distinct from conventional ameloblastoma but remains unknown. We assessed CTNNB1 (beta-catenin) exon 3 mutations in a cohort of 11 samples of adenoid ameloblastomas from 9 patients. Two of the 9 patients were female and 7 male and in 7/9 patients the tumors occurred in the maxilla. Tumors of 4 of these 9 patients harbored CTNNB1 mutations, specifically p.Ser33Cys, p.Gly34Arg, and p.Ser37Phe. Notably, for one patient 3 samples were analyzed including the primary tumour and two consecutive recurrences, and results were positive for the mutation in all three tumors. Therefore, 6/11 samples tested positive for the mutation. In the 6 mutation-positive samples, ghost cells were present in only 2/6, indicating beta-catenin mutations are not always revealed by ghost cell formation. Dentinoid matrix deposition was observed in 5/6 mutation-positive samples and clear cells in all 6 cases. None of the cases harbored either BRAF or KRAS mutations. Beta-catenin immunoexpression was assessed in the samples of 8 patients. Except for one wild-type case, all cases showed focal nuclear expression irrespective of the mutational status. Together with the absence of BRAF mutation, the detection of beta-catenin mutation in adenoid ameloblastomas supports its classification as a separate entity, and not as a subtype of ameloblastoma. The presence of this mutation may help in the diagnosis of challenging cases.

Quantitative proteomic study reveals differential expression of matricellular proteins between fibrous dysplasia and cemento-ossifying fibroma pathogenesis.

BACKGROUND: Fibrous dysplasia (FD) and cemento-ossifying fibroma (COF) are the most common gnathic fibro-osseous lesions. These diseases exhibit remarkable overlap of several clinicopathological aspects, and differential diagnosis depends on the combination of histopathological, radiographic, and clinical aspects. Their molecular landscape remains poorly characterized, and herein, we assessed their proteomic and phosphoproteomic profiles. METHODS: The quantitative differences in protein profile of FD and COF were assessed by proteomic and phosphoproteomic analyses of formalin-fixed paraffin-embedded tissue samples. Pathway enrichment analyses with differentially regulated proteins were performed. RESULTS: FD and COF exhibited differential regulation of pathways related to extracellular matrix organization, cell adhesion, and platelet and erythrocytes activities. Additionally, these lesions demonstrated distinct abundance of proteins involved in osteoblastic differentiation and tumorigenesis and differential abundance of phosphorylation of Ser61 of Yes-associated protein 1 (YAP1). CONCLUSIONS: In summary, despite the morphological similarity between these diseases, our results demonstrated that COF and DF present numerous quantitative differences in their proteomic profiles. These findings suggest that these fibro-osseous lesions trigger distinct molecular mechanisms during their pathogenesis. Moreover, some proteins identified in our analysis could serve as potential biomarkers for differential diagnosis of these diseases after further validation.

Exploring a Region on Chromosome 8p23.1 Displaying Positive Selection Signals in Brazilian Admixed Populations: Additional Insights Into Predisposition to Obesity and Related Disorders.

We recently reported a deviation of local ancestry on the chromosome (ch) 8p23.1, which led to positive selection signals in a Brazilian population sample. The deviation suggested that the genetic variability of candidate genes located on ch 8p23.1 may have been evolutionarily advantageous in the early stages of the admixture process. In the present work, we aim to extend the previous work by studying additional Brazilian admixed individuals and examining DNA sequencing data from the ch 8p23.1 candidate region. Thus, we inferred the local ancestry of 125 exomes from individuals born in five towns within the Southeast region of Brazil (São Paulo, Campinas, Barretos, and Ribeirão Preto located in the state of São Paulo and Belo Horizonte, the capital of the state of Minas Gerais), and compared to data from two public Brazilian reference genomic databases, BIPMed and ABraOM, and with information from the 1000 Genomes Project phase 3 and gnomAD databases. Our results revealed that ancestry is similar among individuals born in the five Brazilian towns assessed; however, an increased proportion of sub-Saharan African ancestry was observed in individuals from Belo Horizonte. In addition, individuals from the five towns considered, as well as those from the ABRAOM dataset, had the same overrepresentation of Native-American ancestry on the ch 8p23.1 locus that was previously reported for the BIPMed reference sample. Sequencing analysis of ch 8p23.1 revealed the presence of 442 non-synonymous variants, including frameshift, inframe deletion, start loss, stop gain, stop loss, and splicing site variants, which occurred in 24 genes. Among these genes, 13 were associated with obesity, type II diabetes, lipid levels, and waist circumference (PRAG1, MFHAS1, PPP1R3B, TNKS, MSRA, PRSS55, RP1L1, PINX1, MTMR9, FAM167A, BLK, GATA4, and CTSB). These results strengthen the hypothesis that a set of variants located on ch 8p23.1 that result from positive selection during early admixture events may influence obesity-related disease predisposition in admixed individuals of the Brazilian population. Furthermore, we present evidence that the exploration of local ancestry deviation in admixed individuals may provide information with the potential to be translated into health care improvement.

Activating genomic alterations in the Gs alpha gene (GNAS) in 274 694 tumors.

Activating point mutations in two codons (R201 and Q227) in the alpha subunit of the stimulatory GTP binding protein (GNAS) gene-coined gsp mutations-were originally reported in growth hormone secreting pituitary adenomas. In these tumor types, gsp activating mutations were associated with uncontrolled intracellular cAMP accumulation leading to cellular proliferation and tumor formation. Since the original description of gsp mutations in pituitary and later thyroid neoplasia, many more tumors were genotyped for these specific activating mutations. In this paradigm, GNAS is an oncogene that can be activated by other molecular mechanisms, such as DNA amplification and translocation. Herein, we describe the largest account to date of tumor types that harbor pathogenic GNAS genomic alterations (GAs) including the "classical" gsp activating point mutations, delineate some common features of these tumors, and speculate as to the possible mechanisms whereby GNAS activating GAs are associated with the various stages of tumorigenesis.

Germline Mutations in Familial Papillary Thyroid Cancer.

Thyroid cancer, predominantly of papillary histology (PTC), is a common cancer mostly diagnosed sporadically. Hereditary PTC is encountered in ~ 5% of cases and may present at an earlier age, with greater risks of metastasis and recurrence, compared with sporadic cases. The molecular basis of hereditary PTC is unknown in most cases. In this study, the genetic basis of hereditary PTC in three Brazilian families was investigated. Whole exome sequencing (WES) was carried out for probands in each family, and validated, pathogenic/likely pathogenic sequence variants (P/LPSVs) were genotyped in additional family members to establish their putative pathogenic role. Overall, seven P/LPSVs in seven novel genes were detected: p.D283N*ANXA3, p.Y157S*NTN4, p.G172W*SERPINA1, p.G188S*FKBP10, p.R937C*PLEKHG5, p.L32Q*P2RX5, and p.Q76*SAPCD1. These results indicate that these novel genes are seemingly associated with hereditary PTC, but extension and validation in other PTC families are required.

Long-term remission of disseminated parathyroid cancer following immunotherapy.

PURPOSE: Parathyroid cancer is a rare tumor associated with poor prognosis particularly when disseminated. While chemotherapy and/or radiotherapy are of no clinical value in disseminated disease, immunotherapy should be considered. SUBJECT AND RESULTS: A patient with CDC73-associated metastatic parathyroid carcinoma was treated with combined anti-hPTH immunotherapy and surgery. CONCLUSIONS: Following five courses of anti-hPTH immunotherapy and subsequent surgery, a 12-year long remission of disseminated parathyroid cancer is reported. This case further supports the ever-expanding spectrum of cancers that may benefit from immunotherapy.

Prevalence of the DPYD variant (Y186C) in Brazilian individuals of African ancestry.

PURPOSE: The presence of deleterious variants of dihydropyrimidine-dehydrogenase gene (DPYD) is associated with 5-Fluorouracil toxicity. Most of the data are based on findings in Caucasian populations. The variant Y186C (rs115232898) is found almost exclusively in African populations and is related to low DPD function. Its prevalence may vary among African subpopulations and in African Americans. There is no information in other populations. Brazil has the biggest African population outside Africa. We studied for the first time the frequency of this mutation in African Brazilians. METHODS: We amplified exon 6 of DPYD extracted from genomic DNA of 79 healthy volunteers of genetically defined African ancestry from Southeast Brazil and 36 self-reported African descendants from Northeast Brazil in order to determine the prevalence of the variant Y186C in Brazilians of African ancestry. RESULTS: The variant Y186C was found in heterozygosity in two samples from Southeast (2.53%) and one from Northeast (2.77%) Brazil. Overall, the prevalence of this mutation in the 115 African Brazilians was 2.6%. CONCLUSIONS: The variant Y186C is prevalent among Brazilians of African ancestry and should be taken in account in targeted genotyping for fluoropyrimidine risk variants.

Lack of association between denture trauma and loss of heterozygosity confronts the proposed pathologic role of chronic mucosal trauma in oral carcinogenesis.

Chronic mucosal trauma is suggested as an additional etiologic risk factor for oral squamous cell carcinoma (OSCC), but there is a lack of experimental-molecular data. If chronic trauma of the oral mucosa is carcinogenic, it should be associated with early genetic alterations seen during typical progression of OSCC, like loss of heterozygosity (LOH). We investigated LOH in the key chromosomal arms 3p, 9p and 17p in inflammatory fibrous hyperplasia associated with removable dental prosthesis and also in normal oral mucosa, by using the polymorphic microsatellite markers D3S1300 at 3p14.2, D9S1748 at 9p21, D17S1289 at 17p12 and D17S974 at 17p13 and capillary electrophoresis. LOH was detected in 2/15 (13%) fibrous hyperplasia samples similarly to other reactive and inflammatory lesions. None of the normal mucosa samples presented LOH. Our experimental-molecular results do not support the hypothesis that trauma associated with dental prosthesis has an important role in oral carcinogenesis.

Molecular and immunohistochemical analyses of uveal melanoma patient cohort.

Uveal melanoma is a rare form of melanoma and the most frequent primary eye malignancy in adults. The major molecular alterations underlying uveal melanoma pathogenesis affect mainly the GNAQ, GNA11, SF3B1, and BAP1 genes. In this study, we somatically genotyped 31 Brazilian uveal melanomas for BRAF, GNA11, GNAQ, SF3B1, and BAP1 gene mutations and assessed BRCA2 and p53 protein expression. GNAQ and GNA11 mutations were detected in 60%, and SF3B1 mutation rate was 30%. p53 Immunostaining was markedly positive in 5/31, and 3/31 samples showed negative BRCA2 expression. This study supports the importance of these key genes in uveal melanoma tumorigenesis; p53 and BRCA pathways seem to play a role in a subset of patients, possibly heralding unfavorable prognosis.