Should we consider sarcopenia in pediatric patients with chronic kidney disease? A preliminary cross-sectional analysis.

BACKGROUND: Pediatric patients with chronic kidney disease (CKD) frequently present an inadequate nutritional profile and musculoskeletal impairments. We investigated sarcopenia and its related traits in children and adolescents with CKD. METHODS: A cross-sectional study that enrolled pediatric patients with CKD (≥ 4 and < 18 years old). Physical function was assessed by handgrip strength and the 60-s sit-to-stand (STS-60) tests. Body composition measurement was performed by bioelectrical impedance analysis and anthropometry through mid-upper arm circumference (MUAC). Normative reference values from healthy pediatrics were used for identifying poor physical function and low MUAC. Probable sarcopenia was considered as low handgrip strength, whereas sarcopenia was defined by adding low MUAC. RESULTS: Twenty-two pediatric patients with CKD (11 ± 4 years and 59% boys) were evaluated; eight on peritoneal dialysis (36%), six on hemodialysis (27%), and eight non-dialysis (36%). Regarding sarcopenia traits, we observed low physical function by handgrip strength and STS-60 in 59% and 100% of the patients, respectively, while low MUAC in 77%. Probable sarcopenia was found in 9% and sarcopenia in 50%, but prevalence did not differ among stages. Handgrip strength was strongly associated with MUAC (r = 0.90; p < 0.001); on the other hand, the STS-60 was not significantly associated with any of the body composition variables. CONCLUSION: Among pediatric patients with CKD, the prevalence of sarcopenia and its related traits was high. Nephrology professionals should consider the assessment of sarcopenia in this population, while more evidence is needed to determine its prognostic value. A higher resolution version of the Graphical abstract is available as Supplementary information.

Making sense of giant cell lesions of the jaws (GCLJ): lessons learned from next-generation sequencing.

Next-generation sequencing has revealed mutations in several bone-related lesions and was recently used to uncover the genetic basis of giant cell lesions of the jaws (GCLJ). Consistent with their benign nature, GCLJ show a low tumor mutation burden. They also harbor somatic, heterozygous, mutually exclusive mutations in TRPV4, KRAS, or FGFR1. These signature mutations occur only in a subset of lesional cells, suggesting the existence of a 'landscaping effect', with mutant cells inducing abnormal accumulation of non-mutant cells that form the tumor mass. Osteoclast-rich lesions with histological similarities to GCLJ can occur in the jaws sporadically or in association with genetically inherited syndromes. Based on recent results, the pathogenesis of a subgroup of sporadic GCLJ seems closely related to non-ossifying fibroma of long bones, with both lesions sharing MAPK pathway-activating mutations. In this review, we extrapolate from these recent findings to contextualize GCLJ genetics and we highlight the therapeutic implications of this new information. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Patient-derived xenografts of a case of ameloblastic fibrodentinoma.

OBJECTIVES: The establishment of animal models of xenotransplantation can contribute to the elucidation of the molecular pathogenesis of ameloblastic fibrodentinomas (AFD) and it also provides an opportunity for drug tests. We aimed to evaluate the possibility of AFD tumour growth in a patient-derived xenograft (PDX) model. In addition, we characterized the human tumour and the PDXs. MATERIALS AND METHODS: A sample of a recurrent AFD was obtained and two fragments were contralaterally implanted subcutaneously in an 8-week old female NUDE mouse. After 250 days, the PDXs were removed and submitted to histopathological and molecular analysis. Immunohistochemical reactions for Ki67 and the phosphorylated form of ERK1/2 were carried out in both, PDXs and human tumour, and the presence of BRAFV600E was assessed. RESULTS: From day 135 onwards, the PDXs presented a growth peak and remained stable until day 250. Histopathologically, the PDXs presented the same features of the patient's tumour. Tumour cells exhibited Ki67 and pERK1/2 immunoexpression in the patient's tumour and PDX. The AFD was wild-type for BRAFV600E. CONCLUSION: The PDX model recapitulated well the human tumour after a long implantation time, representing a possible model to study the AFD and other odontogenic tumours pathobiology.

Ameloblastic carcinoma: a Brazilian collaborative study of 17 cases.

AIMS: Ameloblastic carcinoma (AMECA) is an odontogenic malignancy that combines the histological features of ameloblastoma and cytological atypia. Because of its rarity, it poses difficulties in diagnosis. The aim of this study was to investigate the socio-demographic data, histopathology, immunohistochemical features, treatment and outcomes of 17 cases. METHODS AND RESULTS: Descriptive statistical analyses were used to portray the clinicopathological data collected, retrospectively. Log-rank tests were performed to determine new prognostic factors. Lesions were immunostained for Ki67, p16, p53, and cytokeratins (CKs), and compared with solid/multicystic ameloblastomas (n = 15). AMECA was mostly diagnosed at a late stage, affecting the posterior mandible of male patients in their fifth decade of life. Recurrence was diagnosed in nearly 90% of treated patients, and metastasis occurred in four patients. The mean number of Ki67-positive cells was 86.4 ± 66 per field. Tumours were focally positive for CK7, CK8, CK14, and CK18, and diffusely positive for CK19, p53, and p16. AMECA showed increased immunoexpression of CK18, CK19, p16, p53 and Ki67 as compared with benign cases. CONCLUSIONS: Our study has contributed to the improved characterization of the epidemiology, prognostic markers, treatment options and outcomes of AMECA. Current criteria must be reviewed to simplify the diagnostic process for these neoplasms.

Association between histopathological features of dysplasia in oral leukoplakia and loss of heterozygosity.

AIMS: Oral leukoplakia (OL) dysplasia is graded on the basis of architectural and cytological features, and grade does not correlate well with malignant transformation. Loss of heterozygosity (LOH) profiles have been validated as risk predictors of OL malignant transformation. We aimed to assess whether the histological parameters used to grade dysplasia show different LOH profiles. METHODS AND RESULTS: Areas of epithelial dysplasia of 29 OL samples were microdissected, and LOH was assessed by use of a panel of 11 microsatellite markers located on chromosomes 3, 9, 11, and 17. Dysplasia was graded, and the cytological and architectural parameters were scored. Dysplasia was graded as mild in 18 samples, moderate in nine, and severe in two. The moderate/severe dysplasias and the mild dysplasias did not show different frequencies of allelic loss. Irregular epithelial stratification was associated with LOH at marker D3S1234 (3p14.2). In addition, the presence of drop-shaped rete ridges and premature keratinization in single cells showed associations with LOH at D9S162 (9p22) and P53 (17p13.1), respectively. CONCLUSIONS: We provide evidence that architectural and cellular changes in OL have different LOH patterns.

Hsp27 (HSPB1) differential expression in normal salivary glands and pleomorphic adenomas and association with an increased Bcl2/Bax ratio.

Pleomorphic adenoma (PA) is the most common salivary gland neoplasm. The Hsp27 (HSPB1) is an antiapoptotic protein whose synthesis follows cytotoxic stresses and result in a transient increase in tolerance to subsequent cell injury. Although Hsp27 is expressed in a range of normal tissues and neoplasms, a wide variation in its expression exists among different cells and tissues types. In certain tumours of glandular origin (such as oesophageal adenocarcinomas), the level of Hsp27 is decreased. In the present study, Hsp27 protein levels were evaluated by enzyme-linked immunosorbent assay (ELISA) in a set of 18 fresh PA and 12 normal salivary gland samples. In addition, we tested if Hsp27 protein levels correlated with p53 expression and cell proliferation index, as well as with the transcriptional levels of Bcl-2-associated X protein (BAX), B cell lymphoma 2 (BCL2) and Caspase 3 in PA. We further tested the association between Hsp27 expression and PA tumour size. While all normal salivary gland samples expressed Hsp27 protein, only half of the PA samples expressed it, resulting in a reduced expression of Hsp27 in PA when compared with normal salivary glands (P = 0.003). The expression levels of this protein correlated positively with a higher messenger ribonucleic acid (mRNA) ratio of Bcl2/Bax (R = 0.631; P = 0.01). In conclusion, a decreased Hsp27 protein expression level in PA was found. In addition, Hsp27 levels correlated positively with the Bcl2/Bax mRNA ratio, suggesting an antiapoptotic effect.

Relationship between microRNA expression levels and histopathological features of dysplasia in oral leukoplakia.

BACKGROUND: Increased expression of microRNAs (miRNAs), miR-21, miR-345, and miR-181b has been demonstrated in oral leukoplakia (OL) that progresses to oral squamous cell carcinoma (OSCC), suggesting a miRNA signature with potential prognostic value. On the basis of these findings, this pilot study aimed to investigate the cytological and histopathological features that are used to grade oral dysplasia and determine associations with the expression of these 3 potentially cancer-related miRNAs. We also compared the expression levels of these miRNAs in OL with normal oral mucosa and OSCC. METHODS: We evaluated miRNA expression by qPCR in 22 samples of OL demonstrating different grades of dysplasia, as well as 17 cases of OSCC, and 6 samples of normal oral mucosa. We associated the miRNAs expression profiles with cytological and histopathological features of OL. RESULTS: OSCC cases showed increased expression of all 3 miRNAs when compared with OL and normal oral mucosa. Increased expression of miR-21 was also observed in OL when compared with normal oral mucosa. We found a higher expression of miR-21 and miR-181b in OL that presented with an increased number of mitotic figures, increased nuclear/cytoplasmic ratio, or hyperchromasia. Increased expression of miR-21 was also detected in OL with abnormally superficial mitosis. Higher expression of miR-345 was observed in OL with an increased number and size of nucleoli or increased nuclear/cytoplasmic ratio. CONCLUSIONS: In conclusion, the present study shows that some cytological and histopathological parameters used to grade dysplasia are associated with altered miRNA expression.

TP53 single nucleotide polymorphism rs1042522 in salivary gland neoplasms.

BACKGROUND: The TP53 single nucleotide polymorphism (SNP) rs1042522 encodes arginine (Arg) or proline (Pro). The Arg variant is more effective at inducing apoptosis than the Pro. METHODS: We assessed this SNP through direct sequencing of benign and malignant salivary neoplasms of Brazilian patients and compared the results with healthy controls' data. BAX, BCL-2, and CASPASE-3 mRNA levels were assessed by quantitative polymerase chain reaction (qPCR) in a set of salivary tumors, and the results were correlated with the tumor genotype. RESULTS: We found a higher frequency of the Arg/Arg genotype in the malignant group. However, the SNP did not influence the age of onset in either benign or malignant tumors. The SNP was not associated with the transcription levels of apoptotic/antiapoptotic genes. CONCLUSION: Malignant salivary neoplasms showed a higher frequency of the allele encoding Arg and a higher frequency of the Arg/Arg genotype. However, the different genotypes did not impact the transcription of genes involved in apoptosis.

Loss of heterozygosity (LOH) in tumour suppressor genes in benign and malignant mixed odontogenic tumours.

Although molecular alterations are reported in different types of odontogenic tumours, their pathogenesis remains to be established. Loss of heterozygosity (LOH) studies allow the identification of minimal regions of deletions of known or putative tumour suppressor genes, the losses of which may promote neoplastic growth. The purpose of this study was to investigate LOH in a set of odontogenic mixed tumours. Tumour suppressor gene loci on 3p, 9p, 11p, 11q and 17p chromosomes were analysed in five samples of ameloblastic fibroma (AF), three samples of ameloblastic fibro-odontoma (AFO) and three samples of ameloblastic fibrosarcoma (AFS). The most frequently lost genetic loci were p53 (17p13, 62%) and CHRNB1 (17p13, 55%). LOH at the chromosome regions 3p24.3, 9p22 and 9p22-p21 was identified only in AFS. No sample showed LOH at the chromosomal loci 3p21.2 and 11q13.4. For the region 9p22-p13, LOH occurred in one sample of AFO. The fractional allelic loss (FAL) was calculated for each sample. The mean FAL of the benign lesions (i.e. AF and AFO) was 22%, whereas the mean FAL of the malignant lesions (i.e. AFS) was 74.6%. In conclusion, our results show a higher FAL in AFS compared to its benign counterparts and reveal a different pattern of LOH of tumour suppressor genes in AFS, which may regulate changes in tumour behaviour.

Polymorphism in the promoter region of the gene for 5-HTT in individuals with aggressive periodontitis.

Susceptibility to and development of periodontal disease have been associated with psychological conditions. Previous studies have associated the presence of polymorphism in the promoter region of the serotonin transporter with several behavioral traits and psychological conditions such as depression, anxiety, and stress. The short allele S has a reduced transcriptional efficiency and is associated with lowered serotonin expression and uptake. The purpose of the present study was to investigate the association between 5-HTTLPR polymorphism and aggressive periodontitis in a sample of Brazilian individuals. This study involved 61 individuals affected by aggressive periodontitis and 71 without periodontitis. Genomic DNA was obtained from oral swabs, amplified by polymerase chain reaction (PCR), and genotyped at 5-HTTLPR. The Chi-square test and multivariate logistic regression were used for statistical analysis. The aggressive periodontitis group displayed a significantly higher occurrence of genotype SS (P < 0.01) and of allele S (P < 0.01). After adjustment for gender and age, it was observed that genotype SS occurred 8 times more frequently in this group. Our findings suggest that 5-HTTLPR polymorphism might be associated with aggressive periodontitis in the Brazilian population.

MicroRNA and oral cancer: future perspectives.

MicroRNAs (miRNAs) are small non-coding RNAs that mediate gene expression at the post-transcriptional level by degrading or repressing target messenger RNAs (mRNA). They are about 22 nucleotides in length and regulate mRNA translation by base pairing to partially complementary sites, predominantly in the 3' untranslated region (3' UTR) of mRNA. In this review, we discuss miRNA biogenesis and function, together with its possible involvement in oral cancer. Despite its great importance in normal cell development and diseases, a small number of studies have attempted to investigate miRNA in oral cancer. Overexpression of oncogenic miRNA may reduce protein products of tumor-suppressor genes. On the other hand, loss of tumor-suppressor miRNA expression may cause elevated levels of oncogenic protein. One or both of these alterations could represent new targets for cancer diagnosis and treatment in the future. Many researchers have focused on genetic and epigenetic alterations in oral squamous cell carcinoma cells. The emergence of miRNA knowledge, and its potential interactive action with such alterations, therefore creates a new understanding of cell transformation.

P21/ WAF1 and cyclin D1 variants and oral squamous cell carcinoma.

BACKGROUND: Genetic factors are known to be involved in oral squamous cell carcinoma (OSCC) development. METHOD: We evaluated a possible association between CCND1 A870G and P21/WAF1 C98A polymorphisms and OSCC, as well as the impact of the genotypes on protein immunoexpression. The study group consisted of 80 individuals with histopathological diagnosis of OSCC and the control group consisted of 80 healthy individuals without oral lesions and matched by age, sex and tobacco usage. The genotypes were studied by the polymerase chain reaction and restriction fragment length polymorphic analysis. Paraffin-embedded sections were used for immunohistochemical analysis. RESULTS: No statistical association between CCND1 and/or P21/WAF1 genotypes and OSCC was demonstrated, although we found that people harbouring the combined presence of at least one variant allele of both genes showed a 1.8 times more chance of developing OSCC compared to the referent genotype. OSCC tumours from individuals with P21 heterozygous genotype showed a significantly higher immunopositivity than tumours from wild-type individuals. CONCLUSION: The present study did not demonstrate a significant association between CCND1 and / or P21 / WAF1 genotypes and OSCC. However, P21 protein expression in OSCC tumours is affected by P21 / WAF1 genotype.