Genetic linkage analysis of head and neck cancer in a Spanish family.

OBJECTIVES: To describe the genetic variants that may be associated with the development of head and neck cancer (HNC) and functionally validating the molecular implications. MATERIALS AND METHODS: A prospective observational study was carried out on a family of 3 generations in which 3 members had developed HNC. Peripheral blood sample was taken in a routine procedure for exome sequencing in one relative and genotyping in the remaining twelve relatives. For the functional analysis all-trans retinoic acid (atRA) was extracted from saliva and serum and measured using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The presence of HPV-DNA. RESULTS: None of the patients smoked or consumed alcohol. The presence of HPV DNA was not detected in any of the biopsied samples. A total amount of 6 members out of 13 (46.15%) carried out the same mutation of CYP26B1 (2p13.2; G>T). The mean plasma concentration of atRA was 3.3109 ± 1.4791 pg/mL for the study family and 4.7370 ± 1.5992 pg/mL for the controls (p = 0.042). CONCLUSION: Lower levels of atRA were confirmed in the study family, which may open the way to the possible relationship between the polymorphism CYP26B1 (2p13.2; G>T) and HNC.

Determination and diagnostic value of CA9 mRNA in peripheral blood of patients with oral leukoplakia.

BACKGROUND: Oral leukoplakia is one of the most common oral premalignant disorder. The classical evaluation through tissue biopsy is not always valid to evaluate the risk of malignization. MATERIAL AND METHODS: RT-qPCR was performed on 47 blood samples (21 patients with leukoplakia, 2 with oral squamous cell carcinoma (OSCC), and 24 healthy patients) and on 11 tissue samples (3 leukoplakia, 4 OSCC, and 4 samples of healthy tissue). RESULTS: There are significant differences in expression between the different groups (F = 4.057, p = .006). The Duncan post hoc test shows that the only group that differentiates is the tumour tissue. Using Wilcoxon test, different covariables of patients with leukoplakia were analysed with respect to the group of healthy patients and no significant differences were observed. CONCLUSIONS: The diagnostic route through liquid biopsy has not been conclusive in this study, but there are significant differences in the levels analysed in the different tissue samples.

The role of carbonic anhydrase IX in hypoxia control in OSCC.

Tumoral microenvironments play a key role in the evolution of solid tumors. Tumor hypoxia is actively involved in the promotion of genetic instability, the invasive capacity of tumor cells, metastasis, and a worsening of the clinical evolution. Endogenous hypoxia markers are controlled by hypoxia-related genes, formed by HIF-1, which is related to several target genes that involve the energy metabolism, angiogenesis, and transmembrane carbonic anhydrases (CAs), mainly CA-IX that is one of the tumor-related carbonic anhydrases. The goal of this paper is to establish the role of CA-IX as a hypoxia marker in OSCC, while analyzing its expression in this type of tumors and its relationship with several clinical and pathological parameters and prognosis, evaluating its relationship with angiogenesis, other hypoxia markers, and clarifying its role in chemotherapy and radiotherapy resistance.

The role of p21Waf1/CIP1 as a Cip/Kip type cell-cycle regulator in oral squamous cell carcinoma (Review).

Oral Squamous Cell Carcinoma (OSCC) is biologically characterized by the accumulation of multiple genetic and molecular alterations that end up clinically characterized as a malignant neoplasm through a phenomenon known as multistep. The members of the Cip/Kip family, specifically p21Waf1/CIP1, are responsible for cell cycle control, blocking the transition from phase G1 to phase S. We made a search of articles of peer-reviewed Journals in PubMed/ Medline, crossing the keywords. The goal of this paper is to determine the relationship between p21Waf1/CIP1 expression and several clinical and pathological aspects of OSCC, their relationship with p53 and HPV, as well as genetic alterations in their expression pattern, their use as a prognosis market in the evolution of precancerous lesions and their roles in anticancer treatments. The results of p21WAF1/CIP1 expression in OSCC showed mixed results in terms of positivity/negativity throughout different studies. It seems that, although p21Waf1/CIP1 expression is controlled in a p53-dependent manner, coexpression of both in OSCC is not intrinsically related. Although the presence of HPV viral oncoproteins increases p21Waf1/CIP1 levels, the small number of studies, have forced us to disregard the hypothesis that HPV infected lesions that present better prognosis are due to a p21Waf1/CIP1-dependent control. The role of p21WAF1/CIP1 as cell-cycle regulator has been well described; however, its relationship to OSCC, the clinical and pathological variables of tumors, HPV and different treatments are not entirely clear. Thus, it would be very interesting to pursue further study of this protein, which may have a significant value for the diagnosis, prognosis and therapy of this type of tumors.

Current trends in miRNAs and their relationship with oral squamous cell carcinoma.

A micro RNA (miRNA) is a single-stranded endogenous, non-coding RNA, with length ranging between 18 and 24 nucleotides and the ability of regulating the expression of other genes on a post-transcriptional level by means of various processes, degradation or repression of target mRNA. miRNAs play a crucial role in regulating fundamental processes such as cell cycle, differentiation and apoptosis; thus, their deregulation can affect normal cell growth and development, and even participate in carcinogenesis. The goals of this paper are: to outline the formation and functions of miRNAs; to determine their role in oral squamous cell carcinoma; to analyze the different miRNAs described and their roles as oncogenes or tumor suppressor genes, depending on their overexpression or subexpression; to describe the different polymorphisms and epigenetic alterations identified; and to determine their role in multidrug resistance.

Expression of CA-IX is associated with advanced stage tumors and poor survival in oral squamous cell carcinoma patients.

INTRODUCTION: Carbonic anhydrases (CAs), a group of ubiquitously expressed metalloenzymes, are involved in numerous physiological and pathological processes, including tumorigenicity. Specifically, CA-IX has been primarily found in hypoxic tumor tissues. MATERIAL AND METHODS: This is a retrospective study of tumors from the Tissue Bank of the Pathology Department of the University Hospital of Santiago de Compostela. We selected 50 oral squamous cell carcinomas (OSCCs) using Tissue Microarray (TMA) technology. The immunohistochemical study was performed to determine CA-IX expression. The resulting data were subject to statistical analysis and survival curves. RESULTS: Of the 50 cases, 23 were detected in early stages (I and II) and 27 in advanced stages (III and IV). In the first year, almost 50% of patients in stages III-IV died, which contrasted with those patients in initial stages who registered a survival rate of 80% (P = 0.019). Regarding the expression of CA-IX, nine cases (18%) were negative, 18 cases (36%) were moderate, while 23 cases (46%) were intense. Tumors in stages I-II showed a positivity of 52.6%; however, in advanced stages, the percentage reached 95.5% (P = 0.002). Regarding CA-IX expression and survival, patients with tumors with strong staining had a lower average survival time (13.8 months) than patients with negative or weak-moderate staining (33.4 and 32.8 months, respectively), log-rank=6.1, P value=0.0484. CONCLUSIONS: Early diagnosis of these tumors is essential to improve patient survival. CA-IX expression augments with increasing tumor stage, probably related with the degree of hypoxia; thus, its measurement can be used as a prognostic factor.

Identification of a new mutation in the human xanthine dehydrogenase responsible for xanthinuria type I.

Objectives: Hereditary xanthinuria is a rare, autosomal and recessive disorder characterized by severe hypouricemia and increased xanthine excretion, caused by a deficiency of xanthine dehydrogenase/oxidase (XDH/XO, EC: 1.17.1.4/1.17.3.2) in type I, or by a deficiency of XDH/XO and aldehyde oxidase (AOX, EC: 1.2.3.1) in type II. Methods: We describe a novel point mutation in the XDH gene in homozygosis found in a patient with very low serum and urine levels of uric acid, together with xanthinuria. He was asymptomatic but renal calculi were discovered during imaging. Results: Additional cases were found in his family and dietary recommendations were made in order to prevent further complications. Conclusions: Hereditary xanthinuria is an underdiagnosed pathology, often found in a routine analysis that shows hypouricemia. It is important for Laboratory Medicine to acknowledge how to guide clinicians in the diagnosis.

Beta-adrenergic receptors in cancer: therapeutic implications.

The beta-adrenergic receptors transduce catecholamine signals to the G protein, which through a cascade of chemical reactions in cells generates highly specific parallel signals. The beta2-adrenergic receptor (ADRB2) is the most involved in the carcinogenic processes. Previous studies have determined the relationship of ADRB2 with various aspects related to cancer. Basically, it seems to be related with cell proliferation and apoptosis, chemotaxis, development of metastasis and tumor growth, and angiogenesis. The purpose of this review is to update the implications of these receptors in the pathogenesis of cancer and study the possible application of agonist drugs and/or antagonists in antitumor therapy.

Intracellular pH regulation in oral squamous cell carcinoma is mediated by increased V-ATPase activity via over-expression of the ATP6V1C1 gene.

Oral squamous cell carcinomas represent more than 90% of all head and neck cancers, and comprise about 4% of all malignancies in western countries. Tumor cell mobility related to increasing intracellular pH results in impaired proliferation and metastasis, suggesting an important role of pH regulation in solid cancer tumorigenesis. The mechanism of physiological pH regulation has been shown to be activated in several solid tumors through constitutive activation of the ATPase complex. How cells regulate this mechanism has not been elucidated in human cancer in detail. The present study, using expression profiling by cDNA array analysis of oral squamous cell carcinoma cells, identified the V-ATPase system as a significant regulatory mechanism. ATP6V1C1 was the most strongly over-expressed gene in oral squamous cell carcinoma at the mRNA level compared to other genes of the V-ATPase complex. These findings provide evidence that intracellular pH regulation is mainly controlled by expression of a single gene, ATP6V1C1, notwithstanding the possible action of other secondary regulatory factors.

V232D mutation in patients with cystic fibrosis: Not so rare, not so mild.

The frequency of some Cystic Fibrosis (CF) Transmembrane Conductance Regulator gene (CFTR) mutations varies between populations. Genetic testing during newborn screening (NBS) for CF can identify less common mutations with low clinical expression in childhood and previously considered mild but not fully characterized, such as the mutation p.Val232Asp (c.695T > A). The aim of this study was to describe CF patients with the V232D mutation. We identify CF children with the V232D mutation detected by NBS and compare them with CF adults with this mutation whose diagnosis was prompted by clinical symptoms in the same period. We studied clinical, biochemical, spirometric, and prognostic features in both populations. NBS program tested 276,523 children during a period of 14 years (2003-2017) and identified 54 cases of CF. Six children (11%) had the V232D mutation. Over the same period, 5 adults (age 37.6 ±â€Š16.29 years old) with symptoms of CF and this mutation were also diagnosed. Follow-up duration was mean 10.1 years for adults and mean 6.5 years for children. In the adult group, lung function was impaired at diagnosis in all patients (Forced Expiratory Volume1-FEV1-67.12% ±â€Š13.09) and worsened in children tested during evolution (FEV1first: 113%; FEV1last: 64%). Pancreatic insufficiency was present in adult group, with recurrent pancreatitis in 1 present. Although with less clinical expression in children, V232D is associated with pulmonary and pancreatic involvement during adulthood and CF cannot be considered mild. This mutation is present in 11% of all patients diagnosed with CF in our region. Its inclusion in some NBS programs should be taken into account in order to improve the prognosis of affected children.

Neurogenic arthrogryposis multiplex congenita and velopharyngeal incompetence associated with chromosome 22q11.2 deletion.

We report a case of neurogenic arthrogryposis multiplex congenita and velopharyngeal incompetence in association with a chromosome 22q11.2 deletion in a 5-month-old boy, the only child of a non-consanguineous couple without relevant antecedents. Specifically, polymerase chain reaction amplification of microsatellite markers revealed a noninherited microdeletion in position D22S306. This phenotype has not been reported previously in association with chromosome 22q11.2 deletions, and these findings raise the possibility that at least some cases of neurogenic arthrogryposis multiplex congenita might be due to genetic defects of this type.

p21{Waf1/CIP1} is a poor diagnostic and prognostic marker for OSCC although its expression increases in patients with N1 regional metastasis.

OBJECTIVES: Downregulation of p21{Waf1/CIP1} (a cyclin-dependent kinase inhibitor) has been reported for mouth cancer. The goal of this article is to quantitatively report expression of p21{Waf1/CIP1} and evaluate its relationship with the clinical and prognostic factors. MATERIALS AND METHODS: this is a retrospective study of 68 patients diagnosed with OSCC. We constructed a tissue microarray to develop an immunohistochemical assessment of p21{Waf1/CIP1} expression. A multivariate analysis using a forward-selection stepwise regression model (Cox, 1972) for predicting survival was performed. RESULTS: The quantitative expression of p21{Waf1/CIP1} showed a statistically significant relationship with the risk of lymph node metastasis, showing a higher expression in patients with homolateral single nodes of less than 3 cm (N1) (X{2}=6.58; p< 0.05). We found no statistically significant relationship with any other clinical or pathological parameters. The Cox univariate regression analysis verifies that the effect of the value of p21{Waf1/CIP1} on survival was not statistically significant (p=0.6). The best predictive multivariate Cox analysis included the covariates: recurrence, p21{Waf1/CIP1}, gender, stage, and dysplasia in the adjacent margin. All these variables showed a statistically significant relationship with survival, except p21{Waf1/CIP1}. CONCLUSION: quantitative determination of p21{Waf1/CIP1} standardizes and facilitates its analysis. Although its expression increases in patients with N1 regional metastasis, the loss of p21{WAF1/CIP1} does not seem to have any relationship with the clinical and pathological variables of the tumors.

The Loss of p16 Expression Worsens the Prognosis of OSCC.

Oral squamous cell carcinoma is the most common neoplasia of the mouth. Downregulation of p16(INK4a) (a cyclin-dependent kinase inhibitor) has been reported for mouth cancer and it is believed that its inactivation is an early event in oral carcinogenesis. The goal of this article is to quantitatively report expression of p16(INK4a) and the state of methylation in oral squamous cell carcinoma, and evaluate its relationship with the clinical and prognostic factors, in addition to setting out a multivariate model that predicts survival. The mean expression of p16(INK4a) was 7.70 (SD=14.07) (F=0.894; P=0.449). According to the semiquantitative analysis, there were statistically significant differences, where 19 cases were negative (<2 %), 11 at initial stages, and 8 at advanced stages (χ(2)=6.016; P<0.05). The methylation of p16(INK4a) was not associated with any of the clinical or pathologic variables. Kaplan-Meier curve showed a better survival for patients in initial stages (40.72 mo) compared to those in advanced stages (28.6 mo) (P<0.01). Survival was also reduced in a statistically significant manner in patients with any degree of dysplasia in the adjacent margin (P<0.05). During univariate Cox regression analysis, it was observed that individuals with relapse had a higher risk (almost 9 times higher) [P<0.001; hazard ratio=8.91; 95% confidence interval (CI), 4.18-19.02]. During the Cox multivariate analysis for each unit of decrease in p16(INK4a), the risk increased by 1.06) (P<0.05; hazard ratio=0.94; 95% CI, 0.89-1.00). p16(INK4a) expression is reduced with advancing tumor stage and its gene silencing is associated with an increased risk of death.

Variable expressivity familial cherubism: woman transmitting cherubism without suffering the disease.

UNLABELLED: Cherubism is classified within the group of benign osteo-fibrous lesions. Aside from facial deformities, it may account for major complications. It has been observed that the disease is caused by a mutation in the gene SH3BP2 (SH3-domain binding protein 2), which is located at chromosome 4pl6.3. Here we present two cases of familial cherubism, uncle and nephew, with variable clinical involvement ("Expressivity"), and one case of a woman (sister and mother, respectively), who transmitted cherubism without suffering the disease. In this article we have shown that, in familial cherubism cases, the mutation is inherited through an autosomal dominant transmission. Mutations affecting gene SH3BP2 cause variable clinical involvement (variable expressivity), involvement can be moderate, severe or may result merely in asymptomatic carriers. Since the possibility of transmission reaches 50% of chances, we believe that it is important to develop genetic counseling for both patients and carriers, in order to prevent or minimize new affected offspring. KEYWORDS: Cherubism; SH3BP2; Expressivity.

Tissue inhibitor of metalloproteinases in oral squamous cell carcinomas - a therapeutic target?

Matrix metalloproteinases (MMPs) are proteases responsible for remodeling the extracellular matrix (ECM) and enabling spreading and metastasis of tumor cells, a common phenomenon in oral squamous cell carcinomas (OSCC). They are strongly blocked by several inhibitors, among which we must highlight, for their specificity and potency, the endogenous tissue inhibitors of metalloproteinases (TIMP-1, -2, -3 and -4). The goal of this paper is to describe the expression of TIMPs in OSCC, determining their relation with clinical, histological and prognostic factors, delving into OSCC regulation mechanisms and discussing the use of exogenous TIMPs to treat this type of tumors. Expression of TIMPs in OSCC is higher in tumors than in normal tissue, which correlates with an increase of metastatic risk and regional lymph node affectation. Although some metalloproteinases inhibitors (MMIs) have shown promising results in the treatment of these tumors, their use in OSCC has not been widely tested; and although some indirect MMIs, like COX-2 inhibitors, flavonoids and endostatin seem to have beneficial effects on the invasive capacity of OSCC through regulation of MMPs and TIMP levels, routine clinical use has not been accepted yet.

The role of the adenomatous polyposis coli (APC) in oral squamous cell carcinoma.

The main cause of death in oral squamous cell carcinomas (OSCC) is metastasis. Intercellular adhesion is mediated by a family of glycoproteins called cadherins and other molecules like catenins and APC (adenomatous polyposis coli) among other. The WNT (wingless-type) gene family is a group of genes, key signaling pathway for embryonic development and oncogenesis. The goal of this paper is to describe the role of the APC gene, and its derivatives, in the carcinogenicity pathway of WNT-1, identifying its role as a tumor suppressor gene in OSCC, while describing the genetic (loss of heterozygosity and mutations) and epigenetic alterations that modulate its expression and evaluate its relationship with the clinicopathological parameters of this type of tumors. As for APC, its activity as a tumor suppressor gene appears muted on a relatively frequent basis in these tumors, either by LOH, mutations or epigenetic control mechanisms, thus resulting in a low degree of agreement between the results of different studies.

What real influence does the proto-oncogene c-myc have in OSCC behavior?

The influence of c-myc in the carcinogenic process has been previously described although in the specific case of oral tumors it has been poorly tested. Myc proteins are a family of proto-oncogenes involved in the cell proliferation regulation, differentiation and apoptosis. The goal of this paper is to describe the functions of c-myc and its role as oncogene, assessing its expression by immunohistochemistry and genetic amplification studies, and studying its relationship with tumoral clinical and pathological variables, and describing genetic and molecular interactions in OSCC.

Hypoxia-inducible factors in OSCC.

Oral squamous cell carcinoma (OSCC) is a characteristic locally aggressive tumor in which hypoxia levels are very high, causing a low response to chemotherapy and providing basic resistance to anticancer drugs. Tumoral hypoxia directly depends on hypoxia-inducible factors (HIF). The goal of this paper is to describe HIF basic biology and tumor cells (HIF-1α, mainly), analyzing the effects of its expression in OSCC, study its relation with other molecules such as nitric oxide (NO), carbonic anhydrase (CA) or VEGF and assess the possibility of its manipulation as a therapeutic target.