3-nitrotyrosine and Carcinoma--Squamous-Cell

The prognosis of human cancer depends on the deregulations of many molecular patterns. In recent years, a great interest in the intracellular signaling mechanisms related to nitric oxide (NO)-induced carcinogenesis has appeared, as one of the most preeminent prognostic markers for many types of neoplasms. In this study, we identify the levels of iNOS and nitrotyrosine in the sample of normal oral mucosa (NOM), oral leukoplakia (OL), and oral squamous cell carcinoma (OSCC).. Quantitative polymerase chain reactions (qPCRs) were utilized to detect the NOS2 levels in fresh-frozen tissue samples of NOM (n = 6), OL (n = 20), and OSCC (n = 15). Moreover, the immunohistochemical method was used to examine the levels of iNOS and nitrotyrosine in 85 cases of OSCC (39 cases without metastases and 46 with metastases), 42 cases of OL, and 16 cases of NOM.. There are rising tendencies in the iNOS mRNA and protein levels during human oral carcinogenesis. Similar findings were obtained in the nitrotyrosine staining. Furthermore, iNOS and nitrotyrosine immunostaining are associated with several clinical-pathological features of OSCC (site, presence of metastasis, staging, recidivism, and survival).. The NO-signaling pathway plays a vital role in the development and progression of human oral dysplastic and neoplastic diseases. Nitrotyrosine was a significant marker for the discrimination of OSCC prognosis and survival.

Topics: Carcinoma, Squamous Cell; Humans; Leukoplakia, Oral; Mouth Neoplasms; Nitric Oxide; Nitric Oxide Synthase Type II; Prognosis; Signal Transduction; Tyrosine

The aim of the study was a determination of the levels of nitric oxide (NO) and its biological markers such as malonyldialdehyde (MDA) and nitrotyrosine in the serum of patients with squamous cell carcinoma (SCC) of the oral cavity and identification of the relationships between NO and those markers. These studies were performed on patients with SCC of the oral cavity before and after treatment. Griess reaction was used for the estimation of the total concentration of NO in serum. The nitrotyrosine level in serum was assessed with an enzyme-linked immunosorbent assay (ELISA) kit, and MDA level using a spectrophotometric assay. Higher concentrations of NO in blood serum were determined in patients with stage IV of the disease before treatment in comparison to the control group and patients with stages II and III of the disease. Moreover, higher concentrations of MDA and nitrotyrosine were determined in the serum of patients in all stages of the disease in comparison to healthy people. After treatment, lower concentrations of NO in the serum of patients with stage IV of the disease were observed in comparison to the amounts obtained prior to treatment. In addition, lower levels of nitrotyrosine in the serum of patients with all stages of the disease were recorded, whereas higher concentrations of MDA were determined in these patients in comparison to results obtained before treatment. The compounds formed with the contribution of NO, such as MDA and nitrotyrosine, may lead to cancer progression in patients with SCC of the oral cavity, and contribute to formation of resistance to therapy in these patients as well. Moreover, the lack of a relationship between concentrations of NO and MDA, and between NO and nitrotyrosine in serum suggests that the process of lipid peroxidation and nitration in patients with SCC does not just depend on NO.

Topics: Aged; Carcinoma, Squamous Cell; Case-Control Studies; Female; Humans; Lipid Peroxidation; Male; Malondialdehyde; Mouth Neoplasms; Nitric Oxide; Statistics, Nonparametric; Tyrosine

The high concentration of nitric oxide (NO) around the gastro-esophageal junction (GEJ) might play an important role in the development of Barrett's esophagus (BE), a precursor of Barrett's adenocarcimona. Although previous studies revealed that the expression of caudal-type homeobox 2 (CDX2), an important marker of BE, might be induced through Epidermal Growth Factor Receptor (EGFR), the roles of NO in this signal transduction remain unclear.. First, we investigated the expressions of EGFR, CDX2 and nitrotyrosine by immunohistochemical study for BE and squamous epithelium of human specimens. Second, we studied the effect of peroxynitrite, peroxynitrite stimulator, SIN-1, or NO donor, NOC7, on the expression of phosphorylated EGFR and CDX2 in KYSE30, an EGFR-rich human esophageal squamous cell carcinoma cell-line. Specific inhibitors for EGFR, AG1478 and small interfering RNA for EGFR (EGFR-siRNA) were employed to elucidate the role of EGFR in the induction of CDX2.. The immunohistochemical study revealed that the expressions of EGFR, CDX2 and nitrotyrosine in BE were stronger than those in squamous epithelium with positive correlations. Exposure to peroxynitrite, SIN-1 or NOC7 induced EGFR phosphorylation and CDX2 expression in dose- and time-dependent manners. Both EGFR phosphorylation and CDX2 induction were significantly diminished by AG 1478 and EGFR-siRNA.. We revealed for the first time that extrinsic NO might directly induce CDX2 expression through EGFR phosphorylation. We suggested that NO had an important role in the development of BE from squamous epithelium around GEJ.

Topics: Barrett Esophagus; Carcinoma, Squamous Cell; CDX2 Transcription Factor; Cell Line, Tumor; Epithelium; ErbB Receptors; Esophagogastric Junction; Homeodomain Proteins; Humans; Immunohistochemistry; Metaplasia; Nitric Oxide; Phosphorylation; Tyrosine

Exposure to ultraviolet radiation (UVR) can lead to a range of deleterious responses in the skin. An important form of damage is the DNA photolesion cyclobutane pyrimidine dimer (CPD). CPDs can be highly mutagenic if not repaired prior to cell division and can lead to UV-induced immunosuppression, making them potentially carcinogenic. UVR exposure also produces vitamin D, a prehormone. Different shapes of the steroid hormone 1α,25-dihydroxyvitamin D₃ [1,25(OH)₂D₃] can produce biological responses through binding either to its cognate nuclear receptor (VDR) to regulate gene transcription or to the VDR associated with plasma membrane caveolae to produce, via signal transduction, nongenomic physiologic responses. Here, we show that both 1,25(OH)₂D₃ and 1α,25(OH)₂-lumisterol (JN), a conformationally restricted analogue that can generate only nongenomic responses, are effective inhibitors of UV damage in an immunocompetent mouse (Skh:hr1) model susceptible to UV-induced tumors. Both 1,25(OH)₂D₃ and JN significantly reduced UVR-induced CPD, apoptotic sunburn cells, and immunosuppression. Furthermore, these compounds inhibited skin tumor development, both papillomas and squamous cell carcinomas, in these mice. The observed reduction of these UV-induced effects by 1,25(OH)₂D₃ and JN suggests a role for these compounds in prevention against skin carcinogenesis. To the best of our knowledge, this is the first comprehensive report of an in vivo long-term biological response generated by chronic dosing with a nongenomic-selective vitamin D steroid.

Topics: Animals; Anticarcinogenic Agents; Apoptosis; Calcitriol; Carcinoma, Squamous Cell; Cell Line; Humans; Immunosuppressive Agents; Mice; Receptors, Calcitriol; Signal Transduction; Skin Neoplasms; Tumor Suppressor Protein p53; Tyrosine; Ultraviolet Rays

The molecular and cellular mechanisms linking chronic inflammation and gastrointestinal malignancy are not known with certainty.. To investigate changes in potential causative factors during progression of esophagus cancer in a population living in high-risk area in Iran.. Formalin-fixed, paraffin-embedded esophageal specimens (n=87) from patients with gastroesophageal reflux disease (GERD), Barrett's metaplasia, adenocarcinoma (ADC) and squamous cells carcinoma (SCC) were collected based on their pathological diagnosis.. Immunohistochemical (IHC) technique was used to study tissue accumulation of P53, P21, cyclooxygenase-2 (COX-2), glutathione S-transferase-P (GST-Pi) and nitrotyrosine (NT) in patients and controls.. P53 expression was not detected in esophageal tissues from normal and GERD samples, whereas it was found positive in Barrett's, ADC, and SCC samples. P21 positive sample was relatively higher in ADC patients as compared to that in SCC (ADC: 52.6%; SCC: 25%). GST-Pi expression was equally accumulated in all the samples. NT was predominantly expressed in ADC (72.7%). COX-2 expression was significantly higher in Barrett's (60.0%) and ADC (66.6%) as compared to that in GERD, SCC and normal. These data were further confirmed by detecting the scores of immunostainings in all the positive samples.. The pathological changes in ADC and SCC samples which were associated with increasing frequency of NT and COX-2 provides further evidence for involvement of these inflammatory factors in progression of esophagus cancer.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Barrett Esophagus; Biomarkers, Tumor; Carcinoma, Squamous Cell; Case-Control Studies; Cyclin-Dependent Kinase Inhibitor p21; Cyclooxygenase 2; Disease Progression; Esophageal Neoplasms; Esophagus; Female; Gastroesophageal Reflux; Glutathione S-Transferase pi; Humans; Immunohistochemistry; Iran; Male; Middle Aged; Precancerous Conditions; Tumor Suppressor Protein p53; Tyrosine; Young Adult

Extremely high rates of squamous cell carcinoma of the esophagus (SCCE) are observed in Iran, reflecting unknown, genetic and/or epidemiological risk factors. Among genetic alterations in SCCE, TP53 mutations are the most frequent, vary among populations, and may provide clues on etiological mechanisms. We have analysed mutations in TP53 (exons 5-8) in 98 SCCE from Iran by temporal temperature gel electrophoresis and direct sequencing. We found 58 mutations in 49 patients (50%), with a high prevalence of C to T transitions at CpG dinucleotides (29.3%). The TP53 mutation pattern in Iran was significantly different from that observed in SCCEs from high incidence areas of China and Western Europe (P=0.007). Moreover, the prevalence of mutations at A : T base pairs (transitions and transversions) was higher in men than in women (38.7% vs 11.1%, P=0.033). COX-2 overexpression was detected in 69% of the cases evaluated (24/35), without significant association with TP53 mutation. Accumulation of nitrotyrosine, a marker of protein damage by excess levels of nitric oxide, was observed in tumor cells in six of 18 [corrected] cases analysed. These results are consistent with the hypothesis that several factors are involved in TP53 mutagenesis in Iran. These factors include a baseline of chronic inflammatory stress, which may have a multiplicative impact on the sensitivity of esophageal cells to exogenous factors of risk.

Topics: Adult; Aged; Aged, 80 and over; Carcinoma, Squamous Cell; China; Chronic Disease; Codon; Codon, Nonsense; CpG Islands; Cyclooxygenase 2; DNA Mutational Analysis; DNA, Neoplasm; Esophageal Neoplasms; Esophagitis; Europe; Exons; Female; Frameshift Mutation; Genes, p53; Humans; Incidence; Iran; Isoenzymes; Male; Membrane Proteins; Middle Aged; Mutation; Neoplasm Proteins; Nitric Oxide; Point Mutation; Prostaglandin-Endoperoxide Synthases; Risk Factors; Sequence Analysis, DNA; Tyrosine

Nitric oxide (NO.) and its metabolic byproducts are implicated in carcinogenesis. We examined a marker of NO.-species' pathologic protein nitrosylation, nitrotyrosine, during head and neck squamous cell carcinoma (HNSCCa) development. Materials and Methods Paraffin-embedded tissue samples of normal oral mucosa, squamous hyperplasia/dysplasia, and HNSCCa were immunohistochemically analyzed for staining intensity using an antinitrotyrosine monoclonal antibody, and correlated with retrospective clinical data.. Significantly higher staining was noted in reactive, dysplastic and HNSCCa samples compared with samples of normal mucosa. Additionally, significant differences in staining were found between various primary sites of the upper aerodigestive tract. Lastly, individual inflammatory cells also stained intensely.. Increasing amounts of nitrotyrosine staining were found in reactive/dysplastic and HNSCCa lesions compared to normal squamous mucosa. Inflammatory cell staining implicates NO. as a possible mediator of immunosuppression. Given these findings, the role of NO. in mutations leading to and the immunosuppression found in HNSCCa warrants further investigation.

Topics: Adult; Analysis of Variance; Carcinoma, Squamous Cell; Culture Techniques; Disease Progression; Female; Head and Neck Neoplasms; Humans; Immunohistochemistry; Male; Middle Aged; Neoplasm Proteins; Nitric Oxide; Reference Values; Staining and Labeling; Statistics, Nonparametric; Tyrosine

We have examined the expression of nitrotyrosine, a marker of peroxynitrite formation, in 55 esophageal cancers by immunohistochemistry. Nitrotyrosine was detected in 21 of 55 (38.2%) esophageal cancers. Comparison of nitrotyrosine expression and the pathological findings showed that there was a significant association between the expression of nitrotyrosine and each of the depth of tumor invasion (P<0.01), occurrence of metastasis (P<0.05), pathological stage (P<0.01), smoking status (P<0.05) and alcohol intake (P<0.05). The survival rate of patients with nitrotyrosine-negative cancer was significantly higher than that of patients with nitrotyrosine-positive cancer (log-rank test, P<0.01). p53 was detected in 29 of 55 (52.7%) esophageal cancers, however, p53 expression did not correlate with nitrotyrosine expression. In conclusion, nitrotyrosine, a product of nitrogen species, is expressed in esophageal squamous cell carcinoma, which suggests that exogenous risk factors, such as tobacco and alcohol, through NO, are associated with carcinogenesis and progression of esophageal squamous cell carcinoma.

Topics: Adult; Aged; Carcinoma, Squamous Cell; Esophageal Neoplasms; Female; Humans; Immunohistochemistry; Male; Middle Aged; Nitric Oxide; Tumor Suppressor Protein p53; Tyrosine

Oxidative/reductive (redox) DNA damage from radical species such as nitric oxide (NO*) are increasingly being implicated in the development of cancer. Moreover, redox-protective cellular mechanisms, such as glutathione S-transferase, may determine cellular susceptibility to this redox-mediated damage.. Formalin-fixed, paraffin-embedded tissue samples of 11 normal oral mucosa, 15 reactive/dysplastic lesions, and 131 head and neck squamous cell carcinomas (HNSCCs) were immunohistochemically stained using a polyclonal antibody against glutathione S-transferase pi (GST-pi). Slides were reviewed in a blinded fashion by the study pathologist (G.K.H.) and intensity was graded, noting the pattern of immunostaining. These staining characteristics were compared with those obtained using monoclonal antibodies against endothelial constitutive nitric oxide synthase (ecNOS) and nitrotyrosine, a marker of NO*'s pathological nitrosylation of proteins on serial sections of the same tissue. Patient charts were reviewed and clinical data collected.. The expression of GST-pi was significantly increased in reactive/dysplastic and HNSCC samples compared with normal squamous mucosa (P < .001 for both). Furthermore, among the carcinomas the expression of GST-pi was significantly increased in higher-grade lesions (P < .02). The expression of GST-pi correlated highly with the expression of ecNOS and nitrotyrosine (P < .0001 for both).. These findings demonstrate that GST-pi is upregulated in conjunction with the NO*-generating ecNOS isoform and implicate GST-pi in protecting HNSCC from the cytotoxic effects of high concentrations of NO* found in the tumor bed.

Topics: Adult; Carcinoma, Squamous Cell; Glutathione S-Transferase pi; Glutathione Transferase; Head and Neck Neoplasms; Humans; Immunohistochemistry; Isoenzymes; Middle Aged; Mouth Mucosa; Nitric Oxide Synthase; Nitric Oxide Synthase Type III; Tyrosine; Up-Regulation