Deciphering Key microRNA Regulated Pathways in Tissue-Engineered Blood Vessels: Implications for Vascular Scaffold Production.

MicroRNAs (miRNAs) are non-coding RNAs involved in the regulation of gene expression associated with cell differentiation, proliferation, adhesion, and important biological functions such as inflammation. miRNAs play roles associated with the pathogenesis of chronic degenerative disorders including cardiovascular diseases. Understanding the influence of miRNAs and their target genes can effectively streamline the identification of key biologically active pathways that are important in the development of vascular grafts through the tissue engineering of blood vessels. To determine miRNA expression levels and identify miRNA target genes and pathways with biological roles in scaffolds that have been repopulated with adipose-derived stem cells (ASCs) generated through tissue engineering for the construction of blood vessels. miRNA quantification assays were performed in triplicate to determine miRNA expression in a total of 20 samples: five controls (natural inferior vena cava), five scaffolds recellularized with ASCs and differentiated into the endothelium (luminal layer), five samples of complete scaffolds seeded with ASCs differentiated into the endothelium (luminal layer) and smooth muscle (extraluminal layer), and five samples of ASC without cell differentiation. Several differentially expressed miRNAs were identified and predicted to modulate target genes with roles in key pathways associated with angiogenesis, vascular system control, and endothelial and smooth muscle regulation, including migration, proliferation, and growth. These findings underscore the involvement of these pathways in the regulatory mechanisms that are essential for vascular scaffold production through tissue engineering. Our research contributes to the knowledge of miRNA-regulated mechanisms, which may impact the design of vascular substitutes, and provide valuable insights for enhancing clinical practice. The molecular pathways regulated by miRNAs in tissue engineering of blood vessels (TEBV) allowed us to elucidate the main phenomena involved in cellular differentiation to constitute a blood vessel, with the main pathways being essential for angiogenesis, cellular differentiation, and differentiation into vascular smooth muscle.

Low muscle mass in lung cancer is associated with an inflammatory and immunosuppressive tumor microenvironment.

BACKGROUND: Computed tomographies (CT) are useful for identifying muscle loss in non-small lung cancer (NSCLC) cachectic patients. However, we lack consensus on the best cutoff point for pectoralis muscle loss. We aimed to characterize NSCLC patients based on muscularity, clinical data, and the transcriptional profile from the tumor microenvironment to build a cachexia classification model. METHODS: We used machine learning to generate a muscle loss prediction model, and the tumor's cellular and transcriptional profile was characterized in patients with low muscularity. First, we measured the pectoralis muscle area (PMA) of 211 treatment-naive NSCLC patients using CT available in The Cancer Imaging Archive. The cutoffs were established using machine learning algorithms (CART and Cutoff Finder) on PMA, clinical, and survival data. We evaluated the prediction model in a validation set (36 NSCLC). Tumor RNA-Seq (GSE103584) was used to profile the transcriptome and cellular composition based on digital cytometry. RESULTS: CART demonstrated that a lower PMA was associated with a high risk of death (HR = 1.99). Cutoff Finder selected PMA cutoffs separating low-muscularity (LM) patients based on the risk of death (P-value = 0.003; discovery set). The cutoff presented 84% of success in classifying low muscle mass. The high risk of LM patients was also found in the validation set. Tumor RNA-Seq revealed 90 upregulated secretory genes in LM that potentially interact with muscle cell receptors. The LM upregulated genes enriched inflammatory biological processes. Digital cytometry revealed that LM patients presented high proportions of cytotoxic and exhausted CD8+ T cells. CONCLUSIONS: Our prediction model identified cutoffs that distinguished patients with lower PMA and survival with an inflammatory and immunosuppressive TME enriched with inflammatory factors and CD8+ T cells.

Survival in patients undergoing surgical resection for brain metastasis from lung cancer and utility of different prognostic scales.

Brain metastases (BM) from lung cancer are among the most common intracranial tumors. Several studies have published scales to estimate the survival of patients with BM. Routine access to molecular diagnostics and modern oncologic treatments, including targeted therapy and immunotherapy, is limited in low- and middle-income countries (LMICs); therefore, incorporating them into recent prognostic scales may diminish the reliability of the scales in LMICs. This retrospective study aimed to determine the survival of 55 patients who were surgically treated for BM from lung cancer at a Brazilian public tertiary teaching hospital between 2012 and 2022. We determined clinical factors associated with survival, and compared observed survival rates with the estimated survival on prognostic scales. The mean overall survival (OS) was 9.3 months (range:0.2-76.5). At univariate analysis, female sex and improved postoperative Karnofsky performance status (KPS) score were associated with longer survival. The median survival did not differ between groups when classified using the Graded Prognostic Assessment (GPA)-2008, Lung-molecular GPA-2017, and Lung-GPA-2021 scales. According to the Diagnosis-Specific (DS)-GPA-2012 scale, there was a significant difference between the groups. In the multivariate Cox regression survival analysis, a higher DS-GPA-2012 and improved postoperative KPS score remained significantly associated with longer survival. In conclusion, this cohort showed a mean OS of < 1 year. Improved KPS score after surgery was associated with increased survival. This cohort DS-GPA scale demonstrated the highest concordance with observed survival, indicating its potential as a valuable tool for patient stratification in surgical treatment decision-making in LMICs.

Circulating Extracellular Vesicles microRNAs Are Altered in Women Undergoing Preterm Birth.

Preterm labor (PTL) and preterm premature rupture of membranes (PPROM) lead to high perinatal morbidity/mortality rates worldwide. Small extracellular vesicles (sEV) act in cell communication and contain microRNAs that may contribute to the pathogenesis of these complications. We aimed to compare the expression, in sEV from peripheral blood, of miRNAs between term and preterm pregnancies. This cross-sectional study included women who underwent PTL, PPROM, and term pregnancies, examined at the Botucatu Medical School Hospital, SP, Brazil. sEV were isolated from plasma. Western blot used to detect exosomal protein CD63 and nanoparticle tracking analysis were performed. The expression of 800 miRNAs was assessed by the nCounter Humanv3 miRNA Assay (NanoString). The miRNA expression and relative risk were determined. Samples from 31 women-15 preterm and 16 term-were included. miR-612 expression was increased in the preterm groups. miR-612 has been shown to increase apoptosis in tumor cells and to regulate the nuclear factor κB inflammatory pathway, processes involved in PTL/PPROM pathogenesis. miR-1253, miR-1283, miR378e, and miR-579-3p, all associated with cellular senescence, were downregulated in PPROM compared with term pregnancies. We conclude that miRNAs from circulating sEV are differentially expressed between term and preterm pregnancies and modulate genes in pathways that are relevant to PTL/PPROM pathogenesis.

Telomere-associated genes and telomeric lncRNAs are biomarker candidates in lung squamous cell carcinoma (LUSC).

In the past decade, research efforts were made to identify molecular biomarkers useful as therapeutic targets in Non-Small Cell Lung Cancer (NSCLC), the most frequent type of lung carcinoma. NSCLC presents different histological subtypes being the most prevalent LUSC (Lung Squamous Cell Cancer) and LUAD (Lung Adenocarcinoma), and only a subset of LUAD patients' present tumors expressing known targetable genetic alterations. Telomeres and its components, including telomerase, the enzyme that replenishes telomeres, have been considered potential cancer biomarkers due to their crucial role in cell proliferation and genome stability. Our study aims to quantify expression changes affecting telomere-associated genes and ncRNAs associated with telomere regulation and maintenance in NSCLC. We first assessed the transcriptome (RNA-Seq) data of NSCLC patients from The Cancer Genome Atlas (TCGA) and then we tested the expression of telomere-associated genes and telomeric ncRNAs (TERC, telomerase RNA component, and TERRA, telomere repeat-containing RNA) in Brazilian NCSLC patient samples by quantitative RT-PCR, using matched normal adjacent tissue samples as the control. We also estimated the mean size of terminal restriction fragments (TRF) of some Brazilian NSCLC patients using telomeric Southern blot. The TCGA analysis identified alterations in the expression profile of TERT and telomere damage repair genes, mainly in the LUSC subtype. The study of Brazilian NSCLC samples by RT-qPCR showed that LUSC and LUAD express high amounts of TERT and that although the mean TRF size of tumor samples was shorter compared to normal cells, telomeres in NSCLC are probably maintained by telomerase. Also, the expression analysis of Brazilian NSCLC samples identified statistically significant alterations in the expression of genes involved with telomere damage repair, as well as in TERC and TERRA, mainly in the LUSC subtype. We, therefore, concluded that telomere maintenance genes are significantly deregulated in NSCLC, representing potential biomarkers in the LUSC subtype.

The Pathway to Cancer Cachexia: MicroRNA-Regulated Networks in Muscle Wasting Based on Integrative Meta-Analysis.

Cancer cachexia is a multifactorial syndrome that leads to significant weight loss. Cachexia affects 50%-80% of cancer patients, depending on the tumor type, and is associated with 20%-40% of cancer patient deaths. Besides the efforts to identify molecular mechanisms of skeletal muscle atrophy-a key feature in cancer cachexia-no effective therapy for the syndrome is currently available. MicroRNAs are regulators of gene expression, with therapeutic potential in several muscle wasting disorders. We performed a meta-analysis of previously published gene expression data to reveal new potential microRNA-mRNA networks associated with muscle atrophy in cancer cachexia. We retrieved 52 differentially expressed genes in nine studies of muscle tissue from patients and rodent models of cancer cachexia. Next, we predicted microRNAs targeting these differentially expressed genes. We also include global microRNA expression data surveyed in atrophying skeletal muscles from previous studies as background information. We identified deregulated genes involved in the regulation of apoptosis, muscle hypertrophy, catabolism, and acute phase response. We further predicted new microRNA-mRNA interactions, such as miR-27a/Foxo1, miR-27a/Mef2c, miR-27b/Cxcl12, miR-27b/Mef2c, miR-140/Cxcl12, miR-199a/Cav1, and miR-199a/Junb, which may contribute to muscle wasting in cancer cachexia. Finally, we found drugs targeting MSTN, CXCL12, and CAMK2B, which may be considered for the development of novel therapeutic strategies for cancer cachexia. Our study has broadened the knowledge of microRNA-regulated networks that are likely associated with muscle atrophy in cancer cachexia, pointing to their involvement as potential targets for novel therapeutic strategies.

DNA rare copy number alterations in Reinke's Edema.

INTRODUCTION: Reinke's Edema (RE) is a laryngeal lesion related to excessive tobacco smoking, voice overuse, and laryngopharyngeal reflux. Although the risk of malignancy has been considered low in literature, RE is classified among precancerous lesions. OBJECTIVES: We investigated DNA Copy Number Alterations (CNAs) in specimens of RE and its potential association with malignant progression. METHODS: We used array-based comparative genomic hybridization (aCGH, Agilent 4 × 180 K platform) to study eight RE cases. All patients were heavy tobacco users for at least 30 years, and none of them progressed to cancer in the follow-up (>8 years). Two RE presented mild dysplasia, one moderate dysplasia, and no histological alterations were found in the remaining five cases. CNAs were compared with the Database of Genomic Variants (DGV) and genes mapped on altered regions had their functions annotated. RESULTS: Six of eight patients showed different rare copy number alterations on chromosomes 2q37.3, 4q13.1, 4q13.3, 7q11.22, 10p14, and 13q34. A gain of the whole chromosome 8 were detected in one case. Of interest, four of eight RE cases showed copy number imbalances involving genes previously described in several tumor types (RASA3, COL6A3, LINC00707, LINP1, SMR3A, and SMR3B). CONCLUSION: The genomic imbalances herein found in RE have the potential to contribute to the phenotype but with limited or no risk of cancer. A long-term follow-up in a large series of patients could clarify the mechanisms involved in the malignant progression of RE.

Bacteriophages M13 and T4 Increase the Expression of Anchorage-Dependent Survival Pathway Genes and Down Regulate Androgen Receptor Expression in LNCaP Prostate Cell Line.

Wild-type or engineered bacteriophages have been reported as therapeutic agents in the treatment of several types of diseases, including cancer. They might be used either as naked phages or as carriers of antitumor molecules. Here, we evaluate the role of bacteriophages M13 and T4 in modulating the expression of genes related to cell adhesion, growth, and survival in the androgen-responsive LNCaP prostatic adenocarcinoma-derived epithelial cell line. LNCaP cells were exposed to either bacteriophage M13 or T4 at a concentration of 1 × 105 pfu/mL, 1 × 106 pfu/mL, and 1 × 107 pfu/mL for 24, 48, and 72 h. After exposure, cells were processed for general morphology, cell viability assay, and gene expression analyses. Neither M13 nor T4 exposure altered cellular morphology, but both decreased the MTT reduction capacity of LNCaP cells at different times of treatment. In addition, genes AKT, ITGA5, ITGB1, ITGB3, ITGB5, MAPK3, and PI3K were significantly up-regulated, whilst the genes AR, HSPB1, ITGAV, and PGC1A were down-regulated. Our results show that bacteriophage M13 and T4 interact with LNCaP cells and effectively promote gene expression changes related to anchorage-dependent survival and androgen signaling. In conclusion, phage therapy may increase the response of PCa treatment with PI3K/AKT pathway inhibitors.

The expression landscape of cachexia-inducing factors in human cancers.

BACKGROUND: Cachexia is a multifactorial syndrome highly associated with specific tumour types, but the causes of variation in cachexia prevalence and severity are unknown. While circulating plasma mediators (soluble cachectic factors) derived from tumours have been implicated with the pathogenesis of the syndrome, these associations were generally based on plasma concentration rather than tissue-specific gene expression levels. Here, we hypothesized that tumour gene expression profiling of cachexia-inducing factors (CIFs) in human cancers with different prevalence of cachexia could reveal potential cancer-specific cachexia mediators and biomarkers of clinical outcome. METHODS: First, we combined uniformly processed RNA sequencing data from The Cancer Genome Atlas and Genotype-Tissue Expression databases to characterize the expression profile of secretome genes in 12 cancer types (4651 samples) compared with their matched normal tissues (2737 samples). We systematically investigated the transcriptomic data to assess the tumour expression profile of 25 known CIFs and their predictive values for patient survival. We used the Xena Functional Genomics tool to analyse the gene expression of CIFs according to neoplastic cellularity in pancreatic adenocarcinoma, which is known to present the highest prevalence of cachexia. RESULTS: A comprehensive characterization of the expression profiling of secreted genes in different human cancers revealed pathways and mediators with a potential role in cachexia within the tumour microenvironment. Cytokine-related and chemokine-related pathways were enriched in tumour types frequently associated with the syndrome. CIFs presented a tumour-specific expression profile, in which the number of upregulated genes was correlated with the cachexia prevalence (r2 : 0.80; P value: 0.002) and weight loss (r2 : 0.81; P value: 0.002). The distinct gene expression profile, according to tumour type, was significantly associated with prognosis (P value ≤ 1.96 E-06). In pancreatic adenocarcinoma, the upregulated CIF genes were associated with tumours presenting low neoplastic cellularity and high leucocyte fraction and not with tumour grade. CONCLUSIONS: Our results present a biological dimension of tumour-secreted elements that are potentially useful to explain why specific cancer types are more likely to develop cachexia. The tumour-specific profile of CIFs may help the future development of better targeted therapies to treat cancer types highly associated with the syndrome.

An Integrated Meta-Analysis of Secretome and Proteome Identify Potential Biomarkers of Pancreatic Ductal Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is extremely aggressive, has an unfavorable prognosis, and there are no biomarkers for early detection of the disease or identification of individuals at high risk for morbidity or mortality. The cellular and molecular complexity of PDAC leads to inconsistences in clinical validations of many proteins that have been evaluated as prognostic biomarkers of the disease. The tumor secretome, a potential source of biomarkers in PDAC, plays a crucial role in cell proliferation and metastasis, as well as in resistance to treatments, which together contribute to a worse clinical outcome. The massive amount of proteomic data from pancreatic cancer that has been generated from previous studies can be integrated and explored to uncover secreted proteins relevant to the diagnosis and prognosis of the disease. The present study aimed to perform an integrated meta-analysis of PDAC proteome and secretome public data to identify potential biomarkers of the disease. Our meta-analysis combined mass spectrometry data obtained from two systematic reviews of the pancreatic cancer literature, which independently selected 20 studies of the secretome and 35 of the proteome. Next, we predicted the secreted proteins using seven in silico tools or databases, which identified 39 secreted proteins shared between the secretome and proteome data. Notably, the expression of 31 genes of these secretome-related proteins was upregulated in PDAC samples from The Cancer Genome Atlas (TCGA) when compared to control samples from TCGA and The Genotype-Tissue Expression (GTEx). The prognostic value of these 39 secreted proteins in predicting survival outcome was confirmed using gene expression data from four PDAC datasets (validation set). The gene expression of these secreted proteins was able to distinguish high- and low-survival patients in nine additional tumor types from TCGA, demonstrating that deregulation of these secreted proteins may also contribute to the prognosis in multiple cancers types. Finally, we compared the prognostic value of the identified secreted proteins in PDAC biomarkers studies from the literature. This analysis revealed that our gene signature performed equally well or better than the signatures from these previous studies. In conclusion, our integrated meta-analysis of PDAC proteome and secretome identified 39 secreted proteins as potential biomarkers, and the tumor gene expression profile of these proteins in patients with PDAC is associated with worse overall survival.

MicroRNA expression profiles in the esophagus of children with caustic stenosis: A pathway towards esophageal cancer?

BACKGROUND: Eighty percent of caustic ingestions occur in children and esophageal neoplasms may develop as a late complication of such injury. The identification of biomarkers is a promising strategy to improve early diagnosis of esophageal cancer or caustic lesions that are at an increased risk of progression. STUDY DESIGN/AIMS: This study aimed at identifying global microRNA (miRNA) expression changes in esophageal mucosa from children with caustic stenosis. The study included 27 biopsy samples from 15 patients. Samples were divided into two groups, according to the time elapsed after injury (N = 15 in Group A, with less than five years of follow-up and N = 12 in Group B, with more than five years of follow-up). miRNA expression profiles were determined in each lesion, compared with normal esophageal tissues from control group. We used the TaqMan Human MicroRNA Arrays (Thermo Fisher) platform. Furthermore, bioinformatic algorithms were used to identify miRNA target genes and biological pathways including miRNAs and their target genes potentially associated with esophageal disease. RESULTS: Thirteen miRNAs were significantly deregulated (9 over- and 4 underexpressed) in patients from Group A. In patients from Group B, two miRNAs were over- and two were underexpressed. Of note, miR-374 and miR-574 were deregulated in Group B patients and have been linked to esophageal tumorigenesis. We identified signal transduction and transcription factor networks with genes strongly related to development and progression of esophageal cancer. CONCLUSION: miRNAs identified here contribute to a better understanding of pathways associated with malignant transformation from caustic stenosis to neoplastic lesions. This study may serve as a basis for validation of miRNAs, including miR-374 and miR-574, as potential biomarkers of early cancer detection.

Tumor Transcriptome Reveals High Expression of IL-8 in Non-Small Cell Lung Cancer Patients with Low Pectoralis Muscle Area and Reduced Survival.

Cachexia is a syndrome characterized by an ongoing loss of skeletal muscle mass associated with poor patient prognosis in non-small cell lung cancer (NSCLC). However, prognostic cachexia biomarkers in NSCLC are unknown. Here, we analyzed computed tomography (CT) images and tumor transcriptome data to identify potentially secreted cachexia biomarkers (PSCB) in NSCLC patients with low-muscularity. We integrated radiomics features (pectoralis muscle, sternum, and tenth thoracic (T10) vertebra) from CT of 89 NSCLC patients, which allowed us to identify an index for screening muscularity. Next, a tumor transcriptomic-based secretome analysis from these patients (discovery set) was evaluated to identify potential cachexia biomarkers in patients with low-muscularity. The prognostic value of these biomarkers for predicting recurrence and survival outcome was confirmed using expression data from eight lung cancer datasets (validation set). Finally, C2C12 myoblasts differentiated into myotubes were used to evaluate the ability of the selected biomarker, interleukin (IL)-8, in inducing muscle cell atrophy. We identified 75 over-expressed transcripts in patients with low-muscularity, which included IL-6, CSF3, and IL-8. Also, we identified NCAM1, CNTN1, SCG2, CADM1, IL-8, NPTX1, and APOD as PSCB in the tumor secretome. These PSCB were capable of distinguishing worse and better prognosis (recurrence and survival) in NSCLC patients. IL-8 was confirmed as a predictor of worse prognosis in all validation sets. In vitro assays revealed that IL-8 promoted C2C12 myotube atrophy. Tumors from low-muscularity patients presented a set of upregulated genes encoding for secreted proteins, including pro-inflammatory cytokines that predict worse overall survival in NSCLC. Among these upregulated genes, IL-8 expression in NSCLC tissues was associated with worse prognosis, and the recombinant IL-8 was capable of triggering atrophy in C2C12 myotubes.

DNA rare copy number alterations in Reinke's Edema

Abstract Introduction: Reinke's Edema (RE) is a laryngeal lesion related to excessive tobacco smoking, voice overuse, and laryngopharyngeal reflux. Although the risk of malignancy has been considered low in literature, RE is classified among precancerous lesions. Objectives: We investigated DNA Copy Number Alterations (CNAs) in specimens of RE and its potential association with malignant progression. Methods: We used array-based comparative genomic hybridization (aCGH, Agilent 4 × 180 K platform) to study eight RE cases. All patients were heavy tobacco users for at least 30 years, and none of them progressed to cancer in the follow-up (>8 years). Two RE presented mild dysplasia, one moderate dysplasia, and no histological alterations were found in the remaining five cases. CNAs were compared with the Database of Genomic Variants (DGV) and genes mapped on altered regions had their functions annotated. Results: Six of eight patients showed different rare copy number alterations on chromosomes 2q37.3, 4q13.1, 4q13.3, 7q11.22, 10p14, and 13q34. A gain of the whole chromosome 8 were detected in one case. Of interest, four of eight RE cases showed copy number imbalances involving genes previously described in several tumor types (RASA3, COL6A3, LINC00707, LINP1, SMR3A, and SMR3B). Conclusion: The genomic imbalances herein found in RE have the potential to contribute to the phenotype but with limited or no risk of cancer. A long-term follow-up in a large series of patients could clarify the mechanisms involved in the malignant progression of RE. Level of evidence: 4.

Ultrastructural analysis and residual DNA evaluation of rabbit vein scaffold.

PURPOSE: To investigate the ultrastructural characteristics and analysis of residual DNA in scaffold models, produced with decellularized vena cava in an experimental model with rabbits. METHODS: Three groups were created for ultrastructural and residual DNA analysis: group 1 - control, consisting of samples of vena cava in natura; group 2 - SD, consisting of vein fragments submitted to 2% sodium deoxycholate decellularization by shaking (160rpm - Shaker News Brunswick Scientific®) for 1 hour at controlled temperature shaker at 37°C; group 3 - SDS, consisting of vein fragments submitted to 1% sodium dodecyl sulfate decellularization under the same previous condition, for 2 hours. RESULTS: The ultrastructural matrix of the blood vessel maintained its vintegrity after either decellularization models. The results of the two quantification methods demonstrated a significant decrease in the DNA content of the decellularized vena cava samples as compared to the control samples and, differed statistically from each other, p <0.05. CONCLUSION: The 2% DS protocol for vein decellularization, in this experimental model, was considered the best protocol because it presented less amount of residual DNA without causing substantial destruction of the extracellular matrix.

Double-hit lymphomas: clinical, morphological, immunohistochemical and cytogenetic study in a series of Brazilian patients with high-grade non-Hodgkin lymphoma.

BACKGROUND: Double-hit lymphomas (DHL) are rare high-grade neoplasms characterized by two translocations: one involving the gene MYC and another involving genes BCL2 or BCL6, whose diagnosis depends on cytogenetic examination. This research studied DHL and morphological and/or immunophenotypic factors associated with the detection of these translocations in a group of high-grade non-Hodgkin lymphoma cases. METHOD: Clinical and morphological reviews of 120 cases diagnosed with diffuse large B-cell lymphoma and Burkitt lymphoma were conducted. Immunohistochemistry (CD20, CD79a, PAX5, CD10, Bcl6, Bcl2, MUM1, TDT and Myc) and fluorescence in situ hybridization for detection of MYC, BCL2 and BCL6 gene translocations were performed in a tissue microarray platform. RESULTS: Three cases of DHL were detected: two with translocations of MYC and BCL2 and one with translocations of MYC and BCL6, all leading to death in less than six months. Among 90 cytogenetically evaluable biopsies, associations were determined between immunohistochemistry and fluorescence in situ hybridization for MYC (p = 0.036) and BCL2 (p = 0.001). However, these showed only regular agreement, indicated by Kappa values of 0.23 [0.0;0.49] and 0.35 [0.13;0.56], respectively. "Starry sky" morphology was strongly associated with MYC positivity (p = 0.01). The detection of three cases of DHL, all resulting in death, confirms the rarity and aggressiveness of this neoplasm. CONCLUSIONS: The "starry sky" morphological pattern and immunohistochemical expression of Myc and Bcl2 represent possible selection factors for additional cytogenetic diagnostic testing.

Classic and molecular cytogenetic analyses reveal chromosomal gains and losses correlated with survival in head and neck cancer patients.

PURPOSE: Genetic biomarkers of head and neck tumors could be useful for distinguishing among patients with similar clinical and histopathologic characteristics but having differential probabilities of survival. The purpose of this study was to investigate chromosomal alterations in head and neck carcinomas and to correlate the results with clinical and epidemiologic variables. EXPERIMENTAL DESIGN: Cytogenetic analysis of short-term cultures from 64 primary untreated head and neck squamous cell carcinomas was used to determine the overall pattern of chromosome aberrations. A representative subset of tumors was analyzed in detail by spectral karyotyping and/or confirmatory fluorescence in situ hybridization analysis. RESULTS: Recurrent losses of chromosomes Y (26 cases) and 19 (14 cases), and gains of chromosomes 22 (23 cases), 8 and 20 (11 cases each) were observed. The most frequent structural aberration was del(22)(q13.1) followed by rearrangements involving 6q and 12p. The presence of specific cytogenetic aberrations was found to correlate significantly with an unfavorable outcome. There was a significant association between survival and gains in chromosomes 10 (P = 0.008) and 20 (P = 0.002) and losses of chromosomes 15 (P = 0.005) and 22 (P = 0.021). Univariate analysis indicated that acquisition of monosomy 17 was a significant (P = 0.0012) factor for patients with a previous family history of cancer. CONCLUSIONS: The significant associations found in this study emphasize that alterations of distinct regions of the genome may be genetic biomarkers for a poor prognosis. Losses of chromosomes 17 and 22 can be associated with a family history of cancer.

PHF21B as a candidate tumor suppressor gene in head and neck squamous cell carcinomas.

A significant association between DNA losses on 22q13.31 and head and neck squamous cell carcinomas (HNSCC) was previously reported by our group. Our data indicated that PHF21B gene, mapped on 22q13.31 and encoding a protein with function of chromatin-mediated transcriptional regulation, might be a putative tumor suppressor gene. To test this hypothesis, gene copy number was assessed in 75 HNSCC and 49 matched peripheral blood samples. PHF21B losses were detected in 43 tumors and were significantly associated with patients with familial history of cancer (P < 0.0001); i.e., 36/43 cases showed a positive family history of cancer and 22/36 had first-degree relatives with cancer (P = 0.049). In attempt to investigate other mechanisms for PHF21B loss of function, DNA sequencing was performed and no mutations were detected. We next evaluated the gene expression levels after inhibition of DNA methylation in nine HNSCC and breast carcinoma cell lines. Additionally, PHF21B expression levels were evaluated in colon cancer HCT116 cells as well as in its counterpart DKO (double knockout of DNMT1 and DNMT3B). The higher expression levels of PHF21B gene detected in DKO cells were inversely correlated with the DNA methylation. Further, DNA methylation in the specific promoter-associated CpG Island was investigated. Interestingly, gene hypermethylation was detected in 13/37 tumors: 5/13 HNSCC cases had family history of cancer in first-degree relatives and 8/13 showed both, DNA methylation and PHF21B losses in the tumor sample. One patient had PHF21B loss in the peripheral blood cells and PHF21B methylation in the tumor sample. Additionally, overexpression of PHF21B in cell lines drastically reduces clonogenic and migratory abilities. These data suggest that PHF21B is a novel tumor suppressor gene that can be inactivated by genetic and epigenetic mechanisms in the human cancer.

DNA gains at 8q23.2: a potential early marker in head and neck carcinomas.

Gains or amplifications involving chromosome arm 8q are one of the most recurrent chromosomal alterations in head and neck tumors. To characterize previously reported gains, we performed fluorescence in situ hybridization (FISH) using the sequences BAC RP1179E1 and 8-centromere PMJ 128 as probes. Gains and/or amplifications were detected in all 19 cases evaluated by FISH. The FISH analysis, but not G-banding, revealed homogeneously staining region in three cases. We conclude that gains of one or more genes on chromosome arm 8q may be important for the early stages of head and neck carcinomas.

Ultrastructural analysis and residual DNA evaluation of rabbit vein scaffold

Abstract Purpose: To investigate the ultrastructural characteristics and analysis of residual DNA in scaffold models, produced with decellularized vena cava in an experimental model with rabbits. Methods: Three groups were created for ultrastructural and residual DNA analysis: group 1 - control, consisting of samples of vena cava in natura; group 2 - SD, consisting of vein fragments submitted to 2% sodium deoxycholate decellularization by shaking (160rpm - Shaker News Brunswick Scientific®) for 1 hour at controlled temperature shaker at 37°C; group 3 - SDS, consisting of vein fragments submitted to 1% sodium dodecyl sulfate decellularization under the same previous condition, for 2 hours. Results: The ultrastructural matrix of the blood vessel maintained its vintegrity after either decellularization models. The results of the two quantification methods demonstrated a significant decrease in the DNA content of the decellularized vena cava samples as compared to the control samples and, differed statistically from each other, p <0.05. Conclusion: The 2% DS protocol for vein decellularization, in this experimental model, was considered the best protocol because it presented less amount of residual DNA without causing substantial destruction of the extracellular matrix.