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1.
Toxicol Appl Pharmacol ; 456: 116256, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36208702

RESUMO

Colorectal cancer (CRC) is estimated as the third most incident cancer and second in mortality worldwide. Moreover, CRC metastasis reduces patients' survival rates. Thus, the study and identification of new compounds with anticancer activity selectively to tumor cells are encouraged in the CRC treatment. Naphtoquinones are compounds with several pharmacologic activities, including antitumoral properties. Therefore, this study aimed to investigate the anticancer mechanism of synthetic 8-Hydroxy-2-(P-Nitrothiophenol)-1,4-Naphthoquinone (CNN16) in colon cancer cell line HCT-116. CNN16 showed an IC50 of 5.32 µM in HCT-116, and 9.36, 10.77, and 24.57 µM in the non-cancerous cells MRC-5, MNP-01, and PMBC, respectively, evaluated by the MTT assay. CNN16 showed an anticlonogenic effect in HCT-116 and induced cell fragmentation identified by flow cytometry analysis. Furthermore, we observed that CNN16 presented genotoxicity and induces reactive oxygen species (ROS) after 3 h of treatment visualized by alkaline comet assay and DCFH-DA dye fluorescence, respectively. Furthermore, CNN16 caused cellular membrane disruption, reduction in the mitochondrial membrane polarization, and the presence of apoptotic bodies and chromatin condensation was visualized by differential stained (HO/FD/PI) in fluorescent microscopy along with PARP1, TP53, BCL-2, and BAX analyzed by RT-qPCR. Results also evidenced inhibition in the migratory process analyzed by wound healing assay. Therefore, CNN16 can be considered as a potential new leader molecule for CRC treatment, although further studies are still necessary to comprehend the effects of CNN16 in in vivo models to evaluate the anti-migratory effect, and toxicology and assure compound safety and selectively.


Assuntos
Antineoplásicos , Neoplasias do Colo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Sobrevivência Celular , Antineoplásicos/farmacologia , Apoptose , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Linhagem Celular , Dano ao DNA , Naftalenos/farmacologia , Linhagem Celular Tumoral , Potencial da Membrana Mitocondrial
2.
Front Oncol ; 12: 812008, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651809

RESUMO

Penile cancer (PC) still presents a health threat for developing countries, in particular Brazil. Despite this, little progress has been made on the study of markers, including molecular ones, that can aid in the correct management of the patient, especially concerning lymphadenectomy. As in other neoplasms, non-coding RNAs (ncRNAs) have been investigated for penile cancer, with emphasis on microRNAs, piRNAs (PIWI-interacting small RNAs), and long non-coding RNAs (LncRNAs). In this context, this review aims to assemble the available knowledge on non-coding RNA linked in PC, contributing to our understanding of the penile carcinogenesis process and addressing their clinical relevance. ncRNAs are part of the novel generation of biomarkers, with high potential for diagnosis and prognosis, orientating the type of treatment. Furthermore, its versatility regarding the use of paraffin samples makes it possible to carry out retrospective studies.

3.
Med Microbiol Immunol ; 211(1): 29-36, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34862564

RESUMO

EBV-associated gastric cancer accounts for about 10% of all gastric carcinomas worldwide. We aimed to verify the prevalence of EBV in gastric adenocarcinoma samples using FISH and qPCR and comparing the results obtained by both techniques. Gastric cancer samples from 191 cases were analyzed. The FISH assay was performed to detect small EBV RNAs (EBER1) and qPCR was performed to detect the EBV-EBNA-1 gene region. Cohen's kappa index and the chi-square test were used to compare the methodologies and investigate correlations with the clinical-pathological data of the gastric adenocarcinoma patients. Most of the patients were men, and the average age was 60 years. The intestinal subtype cancer presented more aggressive stages with 90% of patients having a reactive FISH for EBV (EBV+), although the virus infection frequency in epithelial gastric tissue was only 1%. No positive association with clinicopathological features and EBV+ was found by FISH. Using qPCR analysis, the percentage of positive samples was lower (52.4%), and a positive association was found in samples from older patients (> 60 years). Interestingly, 71 qPCR-negative cases were detected by FISH in the presence of non-epithelial cells and in 10 qPCR-positive cases with no evidence of EBV according to FISH. The concordance between the two techniques was low, with only 57.6%. FISH is more informative for associating the gastric carcinoma with EBV positivity in tumor/epithelial cells; however, qPCR can provide relevant information regarding the progression and characteristics of neoplasia.


Assuntos
Adenocarcinoma , Infecções por Vírus Epstein-Barr , Neoplasias Gástricas , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Herpesvirus Humano 4/genética , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia
4.
Cancers (Basel) ; 13(13)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34206307

RESUMO

Gastric cancer (GC) is a worldwide health problem, making it one of the most common types of cancer, in fifth place of all tumor types, and the third highest cause of cancer deaths in the world. There is a subgroup of GC that consists of tumors infected with the Epstein-Barr virus (EBV) and is characterized mainly by the overexpression of programmed cell death protein-ligand-1 (PD-L1). In the present study, we present histopathological and survival data of a thousand GC patients, associated with EBV status and PD-L1 expression. Of the thousand tumors analyzed, 190 were EBV-positive and the vast majority (86.8%) had a high relative expression of mRNA and PD-L1 protein (p < 0.0001) in relation to non-neoplastic control. On the other hand, in EBV-negative samples, the majority had a low PD-L1 expression of RNA and protein (p < 0.0001). In the Kaplan-Meier analysis, the probability of survival and increased overall survival of EBV-positive GC patients was impacted by the PD-L1 overexpression (p < 0.0001 and p = 0.004, respectively). However, the PD-L1 low expression was correlated with low overall survival in those patients. Patients with GC positive for EBV, presenting PD-L1 overexpression can benefit from immunotherapy treatments and performing the quantification of PD-L1 in gastric neoplasms should be adopted as routine.

5.
World J Gastroenterol ; 24(43): 4928-4938, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30487702

RESUMO

AIM: To correlate Helicobacter pylori (H. pylori), Epstein-Barr virus (EBV) and human papillomavirus (HPV) with gastric cancer (GC) cases in Pará State, Brazil. METHODS: Tissue samples were obtained from 302 gastric adenocarcinomas. A rapid urease test was used to detect the presence of H. pylori, and the presence of the cagA gene in the HP-positive samples was confirmed by PCR. An RNA in situ hybridization test designed to complement Eber1 RNA was used to detect the presence of EBV in the samples, and the L1 region of HPV was detected using nested PCR. Positive HPV samples were genotyped and analyzed for E6 and E7 viral gene expression. Infections were also correlated with the clinical and pathological characteristics of the patients. RESULTS: The majority of the 302 samples analyzed were obtained from men (65%) aged 55 years or older (67%) and were classified as the intestinal subtype (55%). All three pathogens were found in the samples analyzed in the present study (H. pylori: 87%, EBV: 20%, HPV: 3%). Overall, 78% of the H. pylori-positive (H. pylori +) samples were cagA+ (H. pylori-cagA +), and there was an association between the cytotoxic product of this gene and EBV. Coinfections of H. pylori-cagA + and EBV were correlated with the most advanced tumor stages. Although only 20% of the tumors were positive for EBV, infection with this virus was associated with distant metastasis. Only the HPV 16 and 18 strains were found in the samples, although no expression of the E6 and E7 oncoproteins was detected. The fundus of the stomach was the region least affected by the pathogens. CONCLUSION: HPV was not involved in gastric tumorigenesis. Prophylactic and therapeutic measures against H. pylori and EBV may prevent the development of GC, especially the more aggressive forms.


Assuntos
Adenocarcinoma/epidemiologia , Coinfecção/epidemiologia , Infecções por Vírus Epstein-Barr/epidemiologia , Infecções por Helicobacter/epidemiologia , Infecções por Papillomavirus/epidemiologia , Neoplasias Gástricas/epidemiologia , Adenocarcinoma/microbiologia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Brasil/epidemiologia , Coinfecção/microbiologia , DNA Bacteriano/isolamento & purificação , DNA Viral/isolamento & purificação , Infecções por Vírus Epstein-Barr/virologia , Feminino , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Helicobacter pylori/isolamento & purificação , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Estômago/microbiologia , Estômago/patologia , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia
6.
BMC Gastroenterol ; 14: 179, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25318991

RESUMO

BACKGROUND: Helicobacter pylori (HP) and Epstein-Barr virus (EBV) have been associated with cancer development. We evaluated the prevalence of HP, HP CagA+ and EBV infection in gastric cancer (GC) samples from adults and in gastric tissues from patients who underwent upper endoscopy (UE). METHODS: Samples from UE and GC were collected to investigate the presence of HP infection and the HP virulence factor CagA by a urease test and PCR. The presence of EBV was detected by Eber-1 in situ hybridization. RESULTS: In UE, 85.5% of juvenile patients showed some degree of gastritis (45.3% of patients with mild gastritis and 54.7% with moderate/severe gastritis) and patients with mild gastritis were younger than patients with moderate/severe gastritis. Among adults, 48.7% presented mild gastritis and 51.3% moderate/severe gastritis. HP infection was detected in 0% of normal mucosa, 58.5% of juvenile gastritis patients, 69.2% of adult gastritis patients and 88% of GC patients. In these same groups, HP CagA+ was detected in 0%, 37.7%, 61.5% and 67.2% of tissue samples, respectively. In juvenile patients, HP infection was more common in those with gastritis than in normal samples (p = 0.004). The patients with either HP or HP CagA+ were older than patients without these pathogens (p < 0.05). In juvenile patients, HP infection was more frequent in cases of moderate/severe gastritis than in cases of mild gastritis (p = 0.026). Moreover, in patients with GC, HP infection was more frequent in males than in females (p = 0.023). GC patients with HP CagA+ were older than patients with HP CagA- (p = 0.027). HP CagA+ was more common in intestinal-type than diffuse-type GC (p = 0.012). HP CagA+ was also associated with lymph-node (p = 0.024) and distal (p = 0.005) metastasis. No association between EBV infection and HP infection or any clinicopathological variable was detected. CONCLUSIONS: Our results suggest that HP is involved in the pathophysiology of severe gastric lesions and in the development of GC, particularly when CagA+ is present. EBV was not the primary pathogenic factor in our samples.


Assuntos
Infecções por Vírus Epstein-Barr/diagnóstico , Gastrite/diagnóstico , Infecções por Helicobacter/diagnóstico , Helicobacter pylori , Neoplasias Gástricas/microbiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antígenos de Bactérias/análise , Proteínas de Bactérias/análise , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/patologia , Gastrite/patologia , Gastroscopia , Infecções por Helicobacter/patologia , Helicobacter pylori/isolamento & purificação , Herpesvirus Humano 4/isolamento & purificação , Humanos , Lactente , Pessoa de Meia-Idade , Estômago/química , Estômago/microbiologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/virologia , Adulto Jovem
7.
BMC Gastroenterol ; 13: 141, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-24053468

RESUMO

BACKGROUND: MYC deregulation is a common event in gastric carcinogenesis, usually as a consequence of gene amplification, chromosomal translocations, or posttranslational mechanisms. FBXW7 is a p53-controlled tumor-suppressor that plays a role in the regulation of cell cycle exit and reentry via MYC degradation. METHODS: We evaluated MYC, FBXW7, and TP53 copy number, mRNA levels, and protein expression in gastric cancer and paired non-neoplastic specimens from 33 patients and also in gastric adenocarcinoma cell lines. We also determined the invasion potential of the gastric cancer cell lines. RESULTS: MYC amplification was observed in 51.5% of gastric tumor samples. Deletion of one copy of FBXW7 and TP53 was observed in 45.5% and 21.2% of gastric tumors, respectively. MYC mRNA expression was significantly higher in tumors than in non-neoplastic samples. FBXW7 and TP53 mRNA expression was markedly lower in tumors than in paired non-neoplastic specimens. Moreover, deregulated MYC and FBXW7 mRNA expression was associated with the presence of lymph node metastasis and tumor stage III-IV. Additionally, MYC immunostaining was more frequently observed in intestinal-type than diffuse-type gastric cancers and was associated with MYC mRNA expression. In vitro studies showed that increased MYC and reduced FBXW7 expression is associated with a more invasive phenotype in gastric cancer cell lines. This result encouraged us to investigate the activity of the gelatinases MMP-2 and MMP-9 in both cell lines. Both gelatinases are synthesized predominantly by stromal cells rather than cancer cells, and it has been proposed that both contribute to cancer progression. We observed a significant increase in MMP-9 activity in ACP02 compared with ACP03 cells. These results confirmed that ACP02 cells have greater invasion capability than ACP03 cells. CONCLUSION: In conclusion, FBXW7 and MYC mRNA may play a role in aggressive biologic behavior of gastric cancer cells and may be a useful indicator of poor prognosis. Furthermore, MYC is a candidate target for new therapies against gastric cancer.


Assuntos
Adenocarcinoma/genética , Proteínas de Ciclo Celular/genética , Variações do Número de Cópias de DNA , Proteínas F-Box/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-myc/genética , Neoplasias Gástricas/genética , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/cirurgia , Adulto , Idoso , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proteínas F-Box/metabolismo , Proteína 7 com Repetições F-Box-WD , Feminino , Perfilação da Expressão Gênica , Humanos , Metástase Linfática/genética , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-myc/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/cirurgia , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
8.
PLoS One ; 8(5): e64420, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23717612

RESUMO

Our study investigated the relationship between MYC alterations and clinicopathological features in gastric cancers. We evaluated the effect of MYC mRNA expression and its protein immunoreactivity, as well as copy number variation, promoter DNA methylation, and point mutations, in 125 gastric adenocarcinoma and 67 paried non-neoplastic tissues. We observed that 77% of the tumors presented MYC immunoreactivity which was significantly associated with increased mRNA expression (p<0.05). These observations were associated with deeper tumor extension and the presence of metastasis (p<0.05). MYC protein expression was also more frequently observed in intestinal-type than in diffuse-type tumors (p<0.001). Additionally, MYC mRNA and protein expression were significantly associated with its copy number (p<0.05). The gain of MYC copies was associated with late-onset, intestinal-type, advanced tumor stage, and the presence of distant metastasis (p<0.05). A hypomethylated MYC promoter was detected in 86.4% of tumor samples. MYC hypomethylation was associated with diffuse-type, advanced tumor stage, deeper tumor extension, and the presence of lymph node metastasis (p<0.05). Moreover, eighteen tumor samples presented at least one known mutation. The presence of MYC mutations was associated with diffuse-type tumor (p<0.001). Our results showed that MYC deregulation was mainly associated with poor prognostic features and also reinforced the presence of different pathways involved in intestinal-type and diffuse-type gastric carcinogenesis. Thus, our findings suggest that MYC may be a useful marker for clinical stratification and prognosis.


Assuntos
Adenocarcinoma/genética , Genes myc , Neoplasias Gástricas/genética , Adenocarcinoma/patologia , Sequência de Bases , Primers do DNA , Feminino , Humanos , Hibridização in Situ Fluorescente , Metástase Linfática/genética , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/genética , Neoplasias Gástricas/patologia
9.
PLoS One ; 8(3): e60576, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23555992

RESUMO

Breast cancer is a complex disease, with heterogeneous clinical evolution. Several analyses have been performed to identify the risk factors for breast cancer progression and the patients who respond best to a specific treatment. We aimed to evaluate whether the hormone receptor expression, HER2 and MYC genes and their protein status, and KRAS codon 12 mutations may be prognostic or predictive biomarkers of breast cancer. Protein, gene and mutation status were concomitantly evaluated in 116 breast tumors from women who underwent neoadjuvant chemotherapy with doxorubicin plus cyclophosphamide. We observed that MYC expression was associated with luminal B and HER2 overexpression phenotypes compared to luminal A (p<0.05). The presence of MYC duplication or polysomy 8, as well as KRAS mutation, were also associated with the HER2 overexpression subtype (p<0.05). MYC expression and MYC gain were more frequently observed in early-onset compared to late-onset tumors (p<0.05). KRAS mutation was a risk factor of grade 3 tumors (p<0.05). A multivariate logistic regression demonstrated that MYC amplification defined as MYC/nucleus ratio of ≥2.5 was a protective factor for chemotherapy resistance. On the other hand, age and grade 2 tumors were a risk factor. Additionally, luminal B, HER2 overexpression, and triple-negative tumors presented increased odds of being resistant to chemotherapy relative to luminal A tumors. Thus, breast tumors with KRAS codon 12 mutations seem to present a worse prognosis. Additionally, MYC amplification may help in the identification of tumors that are sensitive to doxorubicin plus cyclophosphamide treatment. If confirmed in a large set of samples, these markers may be useful for clinical stratification and prognosis.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Mama/patologia , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-myc , Proteínas Proto-Oncogênicas , Proteínas ras , Adulto , Idoso , Idoso de 80 Anos ou mais , Mama/efeitos dos fármacos , Mama/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Estudos de Coortes , Feminino , Genes myc , Humanos , Pessoa de Meia-Idade , Mutação , Terapia Neoadjuvante , Prognóstico , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas p21(ras) , Receptor ErbB-2/genética , Proteínas ras/genética
10.
BMC Gastroenterol ; 12: 85, 2012 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-22768805

RESUMO

BACKGROUND: Gastric cancer is a serious public health problem in Northern Brazil and in the world due to its high incidence and mortality. Despite the severity of the disease, more research is needed to better understand the molecular events involved in this intestinal-type gastric carcinogenesis process. Since precancerous lesions precede intestinal-type gastric cancer, here, we evaluated the hTERT, MYC, and TP53 mRNA and protein expression, as well as TP33 copy number, in gastric preneoplastic lesions. METHODS: We evaluated 19 superficial gastritis, 18 atrophic gastritis, and 18 intestinal metaplasia from cancer-free individuals of Northern Brazil. Quantitative reverse transcription PCR was used to analyze the mRNA expression and immunohistochemical methods were used to assess protein immunoreactivity in tissue samples. The number of TP53 gene copies was investigated in gastric diseases by quantitative PCR. RESULTS: We observed hTERT, MYC, and p53 immunoreactivity only in intestinal metaplasia samples. The immunoreactivity of these proteins was strongly associated with each other. A significantly higher MYC mRNA expression was observed in intestinal metaplasia compared to gastritis samples. Loss of TP53 was also only detected in intestinal metaplasia specimens. CONCLUSIONS: We demonstrated that hTERT, MYC, and TP53 are deregulated in intestinal metaplasia of individuals from Northern Brazil and these alterations may facilitate tumor initiation.


Assuntos
Lesões Pré-Cancerosas/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Neoplasias Gástricas/metabolismo , Telomerase/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Brasil , Transformação Celular Neoplásica/metabolismo , Feminino , Gastrite/genética , Gastrite/metabolismo , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Imuno-Histoquímica , Masculino , Metaplasia/genética , Metaplasia/metabolismo , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , Proteínas Proto-Oncogênicas c-myc/análise , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Telomerase/análise , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/genética
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