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Oropharyngeal cancer (OPC), which is a common type of head and neck squamous cell carcinoma (HNSCC), is associated with tobacco and alcohol use, and human papillomavirus (HPV) infection. Underlying mechanisms and as a result prognosis of the HPV-positive and HPV-negative OPC patients are different. Like stem cells, the ability of self-renewal and differentiate, cancer stem cells (CSCs) have roles in tumor invasion, metastasis, drug resistance, and recurrence after therapy. Research revealed their roles to some extent in all of these processes but there are still many unresolved points to connect to CSC-targeted therapy. In this review, we will focus on what we currently know about CSCs of OPC and limitations of our current knowledge. We will present perspectives that will broaden our understanding and recent literature which may connect to therapy.
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Idiopathic pulmonary fibrosis (IPF) is the most common and most deadly form of interstitial lung disease. Osteopontin (OPN), a matricellular protein with proinflammatory and profibrotic properties, plays a major role in several fibrotic diseases, including IPF; OPN is highly upregulated in patients' lung samples. In this study, we knocked down OPN in a bleomycin (BLM)-induced pulmonary fibrosis (PF) mouse model using small interfering RNA (siRNA) to determine whether the use of OPN siRNA is an effective therapeutic strategy for IPF. We found that fibrosing areas were significantly smaller in specimens from OPN siRNA-treated mice. The number of alveolar macrophages, neutrophils, and lymphocytes in bronchoalveolar lavage fluid was also reduced in OPN siRNA-treated mice. Regarding the expression of epithelial-mesenchymal transition (EMT)-related proteins, the administration of OPN-siRNA to BLM-treated mice upregulated E-cadherin expression and downregulated vimentin expression. Moreover, in vitro, we incubated the human alveolar adenocarcinoma cell line A549 with transforming growth factor (TGF)-ß1 and subsequently transfected the cells with OPN siRNA. We found a significant upregulation of Col1A1, fibronectin, and vimentin after TGF-ß1 stimulation in A549 cells. In contrast, a downregulation of Col1A1, fibronectin, and vimentin mRNA levels was observed in TGF-ß1-stimulated OPN knockdown A549 cells. Therefore, the downregulation of OPN effectively reduced pulmonary fibrotic and EMT changes both in vitro and in vivo. Altogether, our results indicate that OPN siRNA exerts a protective effect on BLM-induced PF in mice. Our results provide a basis for the development of novel targeted therapeutic strategies for IPF.
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Bleomicina/farmacologia , Transição Epitelial-Mesenquimal/genética , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Osteopontina/genética , Células A549 , Animais , Líquido da Lavagem Broncoalveolar , Linhagem Celular Tumoral , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/genética , Regulação para Cima/genéticaRESUMO
The case of a 69-year-old man with bilateral synchronous tonsillar carcinoma is reported. The patient complained of nasal closure, strange voice, and discomfort in his pharynx when he was admitted to the Department of Otolaryngology Head and Neck Surgery at Wakayama Medical University, Wakayama, Japan, in March 2017. The palatine tonsils were enlarged and the surface was irregular. Left cervical lymphadenopathy was also evident. Histological examination from both tonsils was performed and bilateral tonsillar squamous cell carcinoma was diagnosed. PCR analysis showed the same HPV-DNA pattern from bilateral tonsils. Concurrent chemoradiotherapy was performed. Total 70 Gy of irradiation (2Gy/day×35 day) was applied to bilateral tonsillar tumours and upper neck. Follow up was conducted every three months and the patient was free of recurrence for three years. Patient's informed consent was taken to publish the case report.
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Alphapapillomavirus , Carcinoma de Células Escamosas , Neoplasias Primárias Múltiplas , Neoplasias Tonsilares , Idoso , Carcinoma de Células Escamosas/terapia , Humanos , Masculino , Tonsila Palatina , Papillomaviridae , Neoplasias Tonsilares/terapiaRESUMO
Anaplastic thyroid cancer (ATC) remains a cancer with one of the worst prognoses, despite novel targeted therapies. The median survival rate has not improved for decades. Epithelial-to-mesenchymal transition (EMT) is a crucial step in physiological processes and in cancer progression, but the underlying mechanisms are not yet fully understood. The current study examined the role of microRNA (miR)-200b in mesenchymal-to-epithelial transition in ATC. Total RNA and miR isolation were performed from ATC cell lines transfected with a miR-200b mimic. After miR-200b mimic transfection, expression levels of E-cadherin, vimentin and zinc finger E-box binding homeobox 1 (ZEB1) were confirmed by reverse transcription-quantitative PCR and western blotting. Additionally, cell migration was evaluated using miR-200b mimic and scrambled negative control-transfected cells. A total of 14 human ATC and 15 non-cancerous human thyroid tissues were immunohistochemically stained and scored as controls for E-cadherin, vimentin and ZEB1. In ATC tissues and cell lines, the mesenchymal marker ZEB1 was significantly upregulated and the epithelial marker E-cadherin was significantly downregulated. Additionally, the mesenchymal marker vimentin was significantly upregulated in ATC tissues and in one ATC cell line. MiR-200b mimic transfection significantly increased vimentin and ZEB1 expression, but E-cadherin expression remained below the measurement sensitivity. Furthermore, miR-200b overexpression decreased cell migration. The current study suggested that miR-200b may regulate the expression levels of mesenchymal markers such as vimentin and ZEB1 in ATC and may promote mesenchymal-to-epithelial transition.
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The underlying mechanisms of resistance to chemoradiotherapy of human papilloma virus (HPV)-negative patients with oropharyngeal cancer (OPC) remain unclear. The present study aimed to characterize cancer stem cells (CSC) of the HPV-negative OPC cell line in terms of chemotherapy resistance. CSCs were isolated through magnetic activated cell sorting using the CSC specific marker aldehyde dehydrogenase 1 antibody, and characterized by sphere formation capacity, immunofluorescence staining, and CSC marker expression. CSC response to cisplatin treatment was evaluated via XTT-assays. Spheres of CSCs of the HPV-negative UTSCC-60A cell line were highly dark holospheres. RNA expression levels of CSC markers OCT4, SOX2, Kruppel-like factor 4 and BMI1 were significantly higher in CSC. CSCs were significantly resistant to cisplatin treatment at various dosages compared with nonCSC. The present study suggested that the proportion of CSCs is very low in the tumor bulk, CSCs are resistant to cisplatin in HPV-negative OPC, which requires further investigation to define their mechanism.
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BACKGROUND: Genetic factors play a large role in cancer, and thus, there is a great desire to understand the effects of different genes in cancer and to also develop gene therapy for better treatments. Therefore, the development of alternative diagnosis and therapy modalities is of utmost importance. The aim of our study was to illuminate the role of ESM1 (endothelial cell-specific molecule-1, also known as Endocan) in proliferation and migration of head and neck cancer, thus helping to pave the way for new treatment modalities and predictive biomarkers. METHODS: ESM1 expression was shown with immunofluorescence assay using confocal laser scanning microscope in primary and metastatic head and neck cancer cells. ESM1 expression was knocked down by RNA interference in head and neck cancer cells. Knockdown efficiency was evaluated by quantitative real-time RT-PCR and Western blot. Cell proliferation and migration assays were performed by xCELLigence real-time cell analysis system. RESULTS: Immunofluorescence assay showed nuclear localization and high expression of ESM1 in primary and metastatic head and neck cancer cells. ESM1 mRNA and protein levels were significantly decreased in ESM1-knockdown cells compared to control. ESM1-knockdown cells showed reduced proliferation and migration activity when compared to control cells. CONCLUSION: These findings suggest that ESM1 has roles on proliferation and migration of head and neck cancer cells.
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Neoplasias de Cabeça e Pescoço/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/farmacologia , Proteínas de Neoplasias/fisiologia , Proteoglicanas/genética , Proteoglicanas/farmacologia , Proteoglicanas/fisiologia , RNA Interferente Pequeno/genética , Biomarcadores Tumorais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Inativação Gênica , Humanos , Fatores de TranscriçãoRESUMO
PURPOSE: MYC is a transcription factor coding gene that is believed to control 15% of the genes in the entire human genome. The central role of c-MYC in cancer pathogenesis makes it a major therapeutic target in field of anticancer agent development. METHODS: We targeted the acetyl-lysine binding modules or bromodomains, which are associated with c-MYC transcriptional activation. RESULTS: Sequence specific inhibition of BET bromodomains with small hairpin RNAs (shRNAs) resulted in cessation of cellular proliferation in different cancer cell lines. Unlike previous studies on inhibition of bromodomains with selective small-molecule inhibitors, our study revealed the significant role of BET bromodomains in solid tumours and also highlighted the ease of RNA interference (RNAi) methodology for inhibition of bromodomain translation. CONCLUSION: The degree of influence of BET bromodomain inhibition on proliferation in five cancer cell lines established it as the major target in malignancies characterized by activation of c-MYC.
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Neoplasias/genética , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Interferente Pequeno/análise , Fatores de Transcrição/genética , Antineoplásicos/química , Proteínas de Ciclo Celular , Clonagem Molecular , Regulação Neoplásica da Expressão Gênica , Terapia Genética/métodos , Genoma Humano , Células HEK293 , Células HT29 , Células HeLa , Células Hep G2 , Humanos , Lisina/química , Células MCF-7 , Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Plasmídeos/metabolismo , Domínios Proteicos , Proteínas Proto-Oncogênicas c-myc/genética , Interferência de RNA , Fatores de Transcrição/metabolismo , Ativação TranscricionalRESUMO
PURPOSE: Recent studies have shown that cancer stem cells are resistant to chemotherapy. The aim of this study was to compare RIF1 gene expression in head and neck, pancreatic cancer and glioma cell lines and the cancer stem cells isolated from these cell lines. METHODS: UT-SCC-74 from Turku University and UT-SCC-74B primary tumor metastasis and neck cancer cell lines, YKG-1 glioma cancer cell line from RIKEN, pancreatic cancer cell lines and ASPC-1 cells from ATCC were grown in cell culture. To isolate cancer stem cells, ALDH-1 for UT-SCC-74 and UT-SCC-74B cell line, CD-133 for YKG-1 cell line and CD-24 for ASPC-1 cell line, were used as markers of cancer stem cells. RNA isolation was performed for both cancer lines and cancer stem cells. RNAs were converted to cDNA. RIF1 gene expression was performed by qRT-PCR analysis. RIF1 gene expression was compared with cancer cell lines and cancer stem cells isolated from these cell lines. The possible effect of RIF1 gene was evaluated. RESULTS: In the pancreatic cells, RIF1 gene expression in the stem cell-positive cell line was 256 time that seen in the stem cell-negative cell line. CONCLUSION: Considering the importance of RIF1 in NHEJ and of NHEJ in pancreatic cancer, RIF1 may be one of the genes that plays an important role in the diagnoses and therapeutic treatment of pancreatic cancer. The results of head and neck and brain cancers are inconclusive and further studies are required to elucidate the connection between RIF1 gene and these other types of cancers.
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Neoplasias Encefálicas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteínas de Ligação a Telômeros/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Neoplásica , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Proteínas de Ligação a Telômeros/genéticaRESUMO
PURPOSE: By investigating the MACC1 gene (metastasis-associated in colon cancer 1) in cancer stem cells (CSC) resistant to chemotherapy and in cancer stem cells (CSC) resistant to chemotherapy and in cancer cells (CS) sensitive to chemotherapy we determineda steady expression in both types of cells in head and neck cancer. In conformity with the result we examined if this gene could be a competitor gene for chemotherapy. According to literature, the MACC1 gene shows a clear expression in head and neck cancer cells [1]. Here we examined MACC1 expression in CSC and investigated it as a possible biomarker. METHODS: Our experiments were performed in the UT -SCC -74 in primary head and neck cancer cell line. We examined the MACC -1 gene expression by Real Time PCR from both isolated CSC and CS. RESULTS: Expression of MACC -1 gene of cancer stem cells showed an two-fold increase compared with cancer cells. Based on the positive expression of MACC1 in both CS and CSC, this gene may serve as a potential biomarker in head and neck cancer. By comparing the results of this study with the novel features of MACC1, two important hypotheses could be examined. The first hypothesis is that MACC1 is a possible transcripton factor in colon cancer, which influences a high expression of CSC in head and neck and affects the expression of three biomarkers of the CSC control group biomarkers. The second hypothesisis is that the positive expression of MACC1 in patients with a malignant prognosis of tongue cancer, which belongs to head and neck cancer types, operates a faster development of CSC to cancer cells.
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Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fatores de Transcrição/metabolismo , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Transativadores , Fatores de Transcrição/genéticaRESUMO
Coffin-Siris syndrome (CSS) (MIM 135900) is characterized by developmental delay, severe speech impairment, distinctive facial features, hypertrichosis, aplasia or hypoplasia of the distal phalanx or nail of the fifth digit and agenesis of the corpus callosum. Recently, it was shown that mutations in the ARID1B gene are the main cause of CSS, accounting for 76% of identified mutations. Here, we report a 15 year-old female patient who was admitted to our clinic with seizures, speech problems, dysmorphic features, bilaterally big, large thumb, café-au-lait (CAL) spots, obesity and hyperinsulinism. First, the patient was thought to have an association of neurofibromatosis and Rubinstein Taybi syndrome. Because of the large size of the NF1 gene for neurofibromatosis and CREBBP gene for Rubinstein Taybi syndrome, whole exome sequence analysis (WES) was conducted and a novel ARID1B mutation was identified. The proband WES test identified a novel heterozygous frameshift mutation c.3394_3395insTA in exon 13 of ARID1B (NM_017519.2) predicting a premature stop codon p.(Tyr1132Leufs*67). Sanger sequencing confirmed the heterozygous c.3394_3395insTA mutation in the proband and that it was not present in her parents indicating de novo mutation. Further investigation and new cases will help to understand this phenomenon better.
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PURPOSE: Pelvic organ prolapse is a multifactorial disorder in which extracellular matrix defects are implicated. Fibrillin-1 level is reduced in stress urinary incontinence. In Marfan syndrome, which is associated with mutations in Fibrillin-1, pelvic floor disorders are commonly observed. We hypothesize that Fibrillin-1 gene expression is altered in pelvic organ prolapse. METHODS: Thirty women undergoing colporrhaphy or hysterectomy because of cystocele, rectocele, cystorectocele, or uterine prolapse were assigned to a pelvic prolapse study group, and thirty women undergone hysterectomy for nonpelvic prolapse conditions were assigned to a control group. Real-time polymerase chain reaction was conducted on vaginal tissue samples to measure the expression of Fibrillin-1. Expression levels were compared between study and control groups by Mann-Whitney U test with Bonferroni revision. RESULTS: Fibrillin-1 gene expression was not significantly lower in the study group than in the control group. Similarly, no significant correlation between Fibrillin-1 levels and grade of pelvic prolapse was found. Age over 40 years (P=0.018) and menopause (P=0.027) were both associated with reduced Fibrillin-1 levels in the pelvic prolapse group, whereas the delivery of babies weighing over 3,500 g at birth was associated with increased Fibrillin-1 expression (P=0.006). CONCLUSIONS: The results did not indicate a significant reduction in Fibrillin-1 gene expression in pelvic prolapse disorders; however, reduced Fibrillin-1 may contribute to increased pelvic organ prolapse risk with age and menopause. Increased Fibrillin-1 gene expression may be a compensatory mechanism in cases of delivery of babies with high birth weight. Further studies are needed for a better understanding of these observations.
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Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction-restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 Câ>âT polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment.
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Metaloproteinases da Matriz/genética , Transtornos Mieloproliferativos/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Pessoa de Meia-Idade , Polimorfismo Genético , Turquia/epidemiologiaRESUMO
BACKGROUND/AIM: Alzheimer disease (AD) is triggered by interactions of multiple genetic and environmental factors. The APOE gene E4 allele is the best-known risk factor for AD, yet it represents a small ratio of genetic factors. According to genome-wide association studies, the BIN1 gene is the second important risk factor for AD, following the APOE gene. We aimed to identify a novel biomarker indicating susceptibility to AD by investigating APOE alleles and BIN1 gene polymorphisms in a Turkish population. MATERIALS AND METHODS: Fifty-three AD patients and 56 controls were included to examine polymorphism and allele frequency of the APOE and BIN1 genes. Genomic DNAs were isolated from whole blood by SDS/proteinase K treatment, phenol-chloroform extraction, and ethanol precipitation. RFLP was done for identification of polymorphisms in the APOE gene and allele-specific PCR was used for the BIN1 gene. RESULTS: Frequency of the APOE E4 allele was higher in the AD patient group, while the frequency of the E2 allele was higher in controls. The E4/E4 genotype was detected in the AD patient group, while this genotype was not observed in the controls. The frequencies of BIN1 alleles were similar in both groups. CONCLUSION: There was a strong association between AD and the APOE E4 allele, while no such relation was observed with BIN1 gene polymorphism.
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Proteínas Adaptadoras de Transdução de Sinal/genética , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Apolipoproteínas E/genética , Proteínas Nucleares/genética , Polimorfismo Genético/genética , Proteínas Supressoras de Tumor/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Diagnóstico Precoce , Feminino , Frequência do Gene , Marcadores Genéticos , Genótipo , Humanos , Masculino , TurquiaRESUMO
PURPOSE: The purpose of this study was to determine the effects of hypericin on MCF-7 (Michigan Cancer Foundation- 7) breast cancer cells, as it is known to exert an antitumor effect on the expression and regulation of ADAMTS1, 3, 10 and the p53 gene in breast cancer cells. METHODS: MFC-7 cells were cultured and subjected separately to various doses (1, 5 and 7.5 µg /mL) hypericin. After 24 hrs, RNA was isolated and transcribed into cDNA. Expression analysis was performed by real time (RT)-PCR and cell survival was determined by the XTT assay. RESULTS: While the expression of ADAMTS1 in MFC-7 cells decreased to 0.04-fold after exposure to 1 µg /mL hypericin, the expression increased by 5.6- and 36-fold with 5 and 7.5 µg/mL, respectively. Furthermore, ADAMTS3 expression in MCF7 cells increased 3.9-fold with the use of 5 µg /mL of hypericin. These concentrations of hypericin did not lead to significant changes in the expression of ADAMTS10 and the p53 gene. Viability of cancer cells as evaluated by the XTT assay showed that hypericin concentration of 7.5 µg /mL led to increased apoptosis of cancer cells. CONCLUSION: The increase in ADAMTS1 expression may prevent metastasis or facilitate the development of an adjuvant factor with tumor-suppressive effects. Hypericin may therefore exert its antitumor and apoptotic effects in MFC-7 cells via ADAMTS1 and ADAMTS3.
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Proteínas ADAM/genética , Antineoplásicos/farmacologia , Perileno/análogos & derivados , Pró-Colágeno N-Endopeptidase/genética , Proteína Supressora de Tumor p53/genética , Proteínas ADAM/fisiologia , Proteínas ADAMTS , Proteína ADAMTS1 , Antracenos , Feminino , Humanos , Células MCF-7 , Perileno/farmacologia , Pró-Colágeno N-Endopeptidase/fisiologia , RNA Mensageiro/análiseRESUMO
Head and neck squamous cell carcinoma (HNSCC) is one of the most frequently occurring types of cancer worldwide. We focused on the fact that the aberrant function of Wnt/ß-catenin signaling is a frequent event in malignancies. Dickkopf (Dkk)-3 is a major negative regulator of Wnt/ß-catenin signaling, which is a known tumor suppressor and is down-regulated in various types of cancer. However, the expression profile of the Dkk-3 protein in HNSCC has not yet been reported. The present study was conducted to investigate Dkk-3 protein expression in 90 cases of HNSCC tissue samples and HNSCC-derived cell lines. In contrast to findings available on other types of cancer, the Western blot analysis revealed that HNSCC cell lines expressed the Dkk-3 protein. In immunohistochemistry, 76 cases (84.4%) out of 90 tissue samples were Dkk-3-positive, whereas only 14 cases (15.6%) were negative. Notably, survival analysis showed that the Dkk-3 (-) group exhibited significantly longer disease-free survival (p=0.038), metastasis-free survival (p=0.013) and longer overall survival (p=0.155). The results showed that the Dkk-3 protein was dominantly expressed and may be involved in carcinogenesis and metastasis in HNSCC. Moreover, the findings suggest that the function of Dkk-3 differs depending on the tissue of origin, and that it may exert an oncogenic function in HNSCC.
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Ameloblastoma is the most frequently encountered odontogenic tumor, characterized by a locally invasive behavior, frequent recurrences, and, although rare, metastatic capacity. Loss or inactivation of tumor suppressor genes (TSGs) allows cells to acquire neoplastic growth. The ING family proteins are tumor suppressors that physically and functionally interact with p53 to perform important roles in apoptosis, DNA repair, cell cycle regulation, and senescence. TP53 genetic alterations were reported to infrequently occur in ameloblastoma. Considering that other TSGs related to TP53 could be altered in this tumor, we focused our study on the ING family genes. We analyzed the loss of heterozygosity (LOH) status of the ING family (ING1-ING5) chromosomal loci in a group of ameloblastomas by microsatellite analysis, and correlated the ING LOH status with clinicopathological characteristics. By using specific microsatellite markers, high frequency of LOH was found at the loci of each ING gene family member (33.3-72.2%). A significant relationship was shown between LOH of D2S 140 (ING5 locus) and solid tumor type (p = 0.02). LOH of ING3MS (ING3 locus) was also high in solid type tumors, showing a near significant association. In addition, a notable tendency toward higher LOH for half of the markers was observed in recurrent cases. LOH of ING family genes appears as a common genetic alteration in solid ameloblastoma. The current study provides interesting novel information regarding the potential prognostic significance of the allelic loss of the ING gene family loci in ameloblastoma tumorigenesis.
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Ameloblastoma/genética , Proteínas de Ciclo Celular/genética , Proteínas de Homeodomínio/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Maxilomandibulares/genética , Perda de Heterozigosidade , Proteínas Nucleares/genética , Transativadores/genética , Proteínas Supressoras de Tumor/genética , Adolescente , Adulto , Idoso , Ameloblastoma/patologia , Criança , Feminino , Genes Supressores de Tumor , Humanos , Proteína 1 Inibidora do Crescimento , Masculino , Pessoa de Meia-IdadeRESUMO
Our previous study showed high frequency of allelic loss at chromosome 2q37 region in oral cancer. This location contains several candidate tumor suppressor genes such as PPP1R7, ILKAP, DTYMK and ING5. We previously showed 3 members of inhibitor of growth (ING) family, ING1, ING3 and ING4 as tumor suppressor gene in head and neck cancer. As ING5 shows high homology with other members of ING genes including highly conserved carboxy-terminal plant homeodomain and nuclear localization signal, we first picked up ING5 and examined it as a possible tumor suppressor in oral cancer. For this aim, mutation and mRNA expression status of ING5 in paired normal and oral squamous cell carcinoma samples were examined by reverse transcription polymerase chain reaction (RT-PCR) and sequencing. Three missense mutations located within leucine zipper like (LZL) finger and novel conserved region (NCR) domains in ING5 protein were detected, probably abrogating its normal function. We also found 5 different alternative splicing variants of ING5. Then, we examined mRNA level of ING5 by quantitative real time reverse transcription polymerase chain reaction (qRT-PCR) analysis, which demonstrated decreased expression of ING5 mRNA in 61% of the primary tumors as compared to the matched normal samples. In conclusion, tumor-specific mutation and downregulation of ING5 mRNA suggested it as a tumor suppressor gene in oral squamous cell carcinoma.
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Carcinoma de Células Escamosas/genética , Neoplasias Bucais/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Regulação para Baixo , Humanos , Mutação , RNA Mensageiro/metabolismoRESUMO
Head and neck squamous cell carcinoma (HNSCC) is a frequently occurring cancer worldwide. Dickkopf (Dkk)-1 gene is suggested to function as tumor suppressor gene (TSG) in several kinds of malignancies. In this study, we performed loss of heterozygosity (LOH) analysis of Dkk-1 and examined the correlation between LOH status and clinicopathological parameters for the first time. A pretty high LOH ratio (50%) was detected. Interestingly, in the cases with Dkk-1 retention group showed less distant metastasis and a tendency of longer disease free survival. These results indicate that Dkk-1 can play a role in HNSCC carcinogenesis and it may also be related to distant metastasis.
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Carcinoma de Células Escamosas/genética , Cromossomos Humanos Par 10 , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Perda de Heterozigosidade , Idoso , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/terapia , Intervalo Livre de Doença , Feminino , Frequência do Gene , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/secundário , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Estimativa de Kaplan-Meier , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do TratamentoRESUMO
We analyzed mutation and expression status of human epidermal growth factor receptor 2 (Her2) in head and neck squamous cell carcinoma (HNSCC) using single strand conformation polymorphism (SSCP) mutation analysis and immunohistochemistry (IHC). Mutations were absent in all 85 cases. Out of 57 cases available for IHC, Her2 protein expression was negative (0) in 40 tumors (70%). Seventeen tumors (29.8%) expressed Her2, among these 13 tumors (22.8%) showed a weak (+1) expression and 4 (7%) showed a moderate expression (+2), none showed a strong (+3) expression. There was not a significant association between expression and any of the patients' clinical variables or prognosis. Our results suggest that Her2 may not be useful as a molecular target in HNSCC.