CDK10, CDK11, FOXO1, and FOXO3 Gene Expression in Alzheimer's Disease Encephalic Samples

Alzheimer's disease (AD) is a progressive neuroinflammatory and neurodegenerative disorder that affects different regions of the brain. Its pathophysiology includes the accumulation of β-amyloid protein, formation of neurofibrillary tangles, and inflammatory processes. Genetic factors are involved in the onset of AD, but they are not fully elucidated. Identification of gene expression in encephalic tissues of patients with AD may help elucidate its development. Our objectives were to characterize and compare the gene expression of CDK10, CDK11, FOXO1, and FOXO3 in encephalic tissue samples from AD patients and elderly controls, from the auditory cortex and cerebellum. RT-qPCR was used on samples from 82 individuals (45 with AD and 37 controls). We observed a statistically significant increase in CDK10 (p = 0.029*) and CDK11 (p = 0.048*) gene expression in the AD group compared to the control, which was most evident in the cerebellum. Furthermore, the Spearman test demonstrated the presence of a positive correlation of gene expression both in the auditory cortex in the AD group (r = 0.046/p = 0.004) and control group (r = 0.454/p = 0.005); and in the cerebellum in the AD group (r = 0.654 /p < 0.001). There was no statistically significant difference and correlation in the gene expression of FOXO1 and FOXO3 in the AD group and the control. In conclusion, CDK10 and CDK11 have high expression in AD patients compared to control, and they present a positive correlation of gene expression in the analyzed groups and tissues, which suggests that they play an important role in the pathogenesis of AD.

Abstract 1491: Investigation of differentially expressed miRNAs in patients with gastric adenocarcinoma

Gastric cancer (GC) is one of the most common cancers and one of the leading causes of cancer related death worldwide. Although the treatment of GC patients has improved during the last decades, thanks to advancements in surgery, radiotherapy and chemotherapy, the long-term survival rates of patients with GC remains around 20%. In addition, late diagnosis usually occurs due to the absence of symptoms or the presence of non-specific symptoms in early stages of the disease. Thus, the continuous study of new strategies for early diagnosis and identification of novel therapeutic approaches is of great interest, to reduce the need for mutilating surgeries and morbid adjuvant therapies. Next-generation sequencing technologies unveiled new roles and functions of RNAs, particularly, non-coding RNAs. Among the most studied molecules, microRNAs (miRNAs) have been reported to play important roles in different physiological and pathological processes, including cancer. Therefore, the goals of this project are (1) to determine the miRNA profile of patients with GC using tumor tissue samples using next-generation sequencing; and (2) to validate the expression profile of differentially expressed (DE) miRNAs in serum from patients with GC. To identify DE microRNAs between GC tissues and gastric tissues from individuals without cancer, 24 samples (17 cancer and 7 controls) were sequenced using the Ion Torrent PGM (Thermo Fisher Scientific) sequencing equipment. Preliminary results indicate that there are 54 DE miRNAs among the 269 known human miRNAs identified, where 44 were upregulated, while 10 were downregulated in samples from GC patients when compared to samples from individuals without cancer. As expected, Over-Representation Analysis (ORA) revealed that the disease most frequently associated with these DE miRNAs is the digestive system neoplasm. Moreover, Gene Set Enrichment Analysis (GSEA) showed that neoplasm metastasis is the phenotype most associated with this subset of DE miRNAs, indicating that these miRNAs possibly contribute to cell invasion and migration in gastric tumors. To confirm these findings, further experiments are now being performed, such as validation of the DE miRNAs by qRT-PCR in tissue and serum of GC samples, as well as functional studies. Thereby, the identification of a circulating signature of miRNAs will allow a better understanding of physiopathology of gastric carcinogenesis and the identification of possible biomarkers, which may help in early diagnosis, prognosis, and development of novel anticancer therapies.Funding: MACS, Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) grant # 2016/25562-0; MACS, Conselho Nacional de Pesquisa (CNPq) grant # 2018/301127-2; MACS, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) 23038051640/2009-01; BTRK, Postdoctoral Fellowship, FAPESP 2019/20592-6; CAP, CAPES Doctoral Fellowship 88882.430351/2019-01.

Citation Format: Bruno Takao Real Karia, Camila Albuquerque Pinto, Leonardo Caires, Yeda Beatriz Louredo dos Santos, Fernanda Wisnieski, Carolina Gigek, Marilia de Arruda Cardoso Smith. Investigation of differentially expressed miRNAs in patients with gastric adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1491.

Dysregulated Expression of Apoptosis-Associated Genes and MicroRNAs and Their Involvement in Gastric Carcinogenesis

PURPOSE

Analyze the expression of caspase-9, Smac/DIABLO, XIAP, let-7a, and let-7b in patients with normal gastric tissue, chronic gastritis, and gastric adenocarcinoma.

METHODS

The expression of caspase-9, Smac/DIABLO, XIAP, let-7a, and let-7b by qRT-PCR was analyzed in 158 samples from 53 patients with normal gastric mucosa, 86 with chronic gastritis, and 19 with gastric cancer.

RESULTS

The comparison between the gastric cancer and the control group revealed a decreased expression of caspase-9 in gastric cancer tissues; considering the Helicobacter pylor presence, comparable results were revealed. Smac/DIABLO was increased in gastric cancer cells, while XIAP demonstrated no significant difference in the gene expression. The microRNA analysis revealed a decreased expression of let-7a and let-7b in samples positive to H. pylori infection and in gastric cancer group, regardless of the presence of the bacterium.

CONCLUSION

Our study provided some evidence of low activity of the intrinsic apoptosis pathway, as well as the influence of H. pylori on let-7a and let-7b expression.

Lack of Association between IL-6 Polymorphisms and Haplotypes with Gastric Cancer

The process of combating neoplasms and mononuclear cells, and during H. pylori infection, several pro-inflammatory and anti-inflammatory cytokines are synthesized. In view of the involvement of the IL-6 law and the presence of H. pylori in the development of gastric diseases, the present study aimed to characterize the promoter-region polymorphism -597 (G/A) (rs1800797), -572 (C/G) (rs1800796), and -174 (G/C) (rs1800795) by PCR-RFLP in 375 gastric biopsy specimens from patients with peptic symptoms. A total of 375 samples were analyzed: 87 patients (without lesion without gastric tissue); 236 patients with gastritis and 52 patients with gastric cancer analyzed the PCR-RFLP techniques. All the results were normalized in relation to the presence of H. pylori. The frequencies of the three polymorphisms were compared in the Control vs Gastritis groups and a statistically significant test observed: -174 (G/C) (OR: 1.27; 95% CI: 0.84-1.93; P = 0.26), 572 (C/G) (OR: 1.42; 95% CI: 0.78-2.59; P = 0.25), and 597 (G/A) (OR: 0.98; 95% CI, 0.64-1.52; P = 0.94). Similar results were obtained when the gastric cancer group was compared to the control group: -174 (G/C) (OR: 1.27; 95% CI: 0.66-2.47; P = 0.47), -572 (C/G) (OR: 1.07; 95% CI: 0.43-2.68; P = 0.88), and -597 (G/A) (OR: 1.01; 95% CI, 0.5-0.9; P = 0.99). The haplotypes were and were not observed statistically significant differences. In conclusion, we found no correlations between any of the three polymorphisms in the IL-6 gene analyzed in this study and a higher risk of gastritis or gastric cancer.

Downregulated Expression of E-cadherin and TP53 in Patients with Gastric Diseases: the Involvement of H. pylori Infection and Its Virulence Markers

PURPOSE

Gastritis caused by infection with Helicobacter pylori is characterized by chronic inflammation and damage in gastric tissue, which is a main risk factor for gastric cancer. Associated with H. pylori, the TP53 gene tumor suppressor and the cell adhesion glycoprotein epithelial cadherin develop a relevant role in the integrity and carcinogenesis of the epithelium. We aimed to detection of H. pylori and its main virulence markers and measured the messenger RNA (mRNA) expression levels of E-cadherin and TP53 genes.

METHODS

The detection of H. pylori and its virulence markers, as well as the mRNA expression levels of E-cadherin and TP53 genes, were obtained for 161 samples of gastric biopsies including 37 with normal gastric tissue, 70 with gastritis, 24 from neoplastic tissue, and 27 from adjacent non-neoplastic by means of a quantitative real-time polymerase chain reaction.

RESULTS

The mRNA expression levels of E-cadherin and TP53 were found to be decreased in patients with gastritis, independently of H. pylori infection. In samples from gastric patients, the neoplastic tissue showed an accentuated decrease of expression; on the other hand, the expression of E-cadherin was normal in adjacent non-neoplastic.

CONCLUSIONS

No evidence was found of the involvement of the cagA and vacA genes in the decreased expression of E-cadherin and TP53. The process of carcinogenesis is complex, and the decrease of the E-cadherin gene expression and TP53 gene expression appears to contribute significantly.

Lack of association among TNF-α gene expression, -308 polymorphism (G > A) and virulence markers of Helicobacter pylori

Background

Tumor necrosis factor plays a critical role in the pathogenesis of gastric diseases such as gastric cancer, and an abnormal inflammatory response has frequently been observed in dyspeptic patients. Helicobacter pylori infection can induce a gastric mucosal inflammatory response that may be influenced by -308 (G > A) polymorphisms and gene expression of the TNF-α gene.

Methods

One hundred and thirty-four gastric biopsy samples were collected from patients of both genders (61♂ and 73♀, mean age 40.3 ± 24.2 years) with gastric symptoms. The -308 (G > A) polymorphism of TNF-α was characterized using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). The expression level was measured using real-time PCR, and relative quantification (RQ) was calculated using the comparative CT method (2^-ΔΔCT).

Results

The analysis revealed an increase in TNF-α gene expression in patients with gastritis; on the other hand, no statistical differences were observed in patients with gastric cancer. In addition, no association was found among -308 polymorphism genotypes, virulence markers, or TNF-α gene expression.

Conclusions

Helicobacter pylori induces a large increase in TNF-α expression in patients with gastritis, regardless of tissue inflammation, but after the tissue becomes neoplastic, the presence of bacteria did not influence expression. These results suggest that the TNF-α pathway may play an important role in the progression from gastritis to gastric cancer

Association study of SNPs of genes IFNGR1 (rs137854905), GSTT1 (rs71748309), and GSTP1 (rs1695) in gastric cancer development in samples of patient in the northern and northeastern Brazil

Cancer is a multifactorial disease with a high mortality rate in Brazil and worldwide. Gastric cancer (GC) is considered the fourth type of malignancy more frequent in the population worldwide and the second leading cause of death. This work aimed to evaluate single nucleotide polymorphisms (SNPs) of IFNGR1, GSTT1, and GSTP1 genes samples in gastric cancer. We analyzed 60 samples of gastric cancer, 26 diffuse and 34 intestinal types, totaling 120 alleles for each SNP. The results were obtained by PCR and allele-specific PCR. Statistical analyzes performed using BioEstat 5.0 software, applying the Fisher's exact test and chi-square. Only the SNP gene GSTP1 (rs1695) were significantly associated with gastric cancer in the samples analyzed (χ(2) = 8.73, P < 0.05). Our results suggest that the GSTP1 gene SNP (rs1695) can be considered a risk factor associated with gastric carcinogenesis.

Pharmacological modulation of cognitive and behavioral symptoms in patients with dementia due to Alzheimer's disease

To evaluate correlations of pharmacological treatment with cognitive and behavioral symptoms in patients with dementia due to Alzheimer's disease with low schooling, subjects were assessed for demographic features, neuropsychiatric symptoms, cognitive decline, functionality, caregiver burden, APOE haplotypes and pharmacological treatment. Among 217 patients, use of cholinesterase inhibitors with or without Memantine was associated with less neuropsychiatric symptoms, while anti-psychotics and/or anti-epileptic drugs were associated with lower instrumental functionality. Anti-psychotics were also associated with more neuropsychiatric symptoms in moderately impaired patients, possibly reflecting the greater need for such treatment when behavioral symptoms are present. Patients receiving more medications were usually younger, obese, married, with higher schooling and more neuropsychiatric symptoms. APOE4+ haplotypes were correlated with earlier dementia onset, but not with pharmacological treatment. Higher caregiver burden was associated with more psychotropic drugs. A trend was found for treatment with cholinesterase inhibitors and Memantine to be associated with longer lengths of dementia for moderately impaired but not for severely impaired patients, regardless of APOE haplotypes, translating into a synergistic effect among such medications for slowing cognitive decline but not for prolonging survival. Further longitudinal studies may be required to assess dose-response relationships regarding treatment with psychotropics for patients with dementia.

SMARCA5 methylation and expression in gastric cancer

Here, we first evaluated SMARCA5 expression and promoter DNA methylation in gastric carcinogenesis. Immunohistochemistry and methylation-specific PCR were analyzed in 19 and 48 normal mucosa and in 52 and 92 gastric cancer samples, respectively. We observed higher immunoreactivity of SMARCA5 in gastric cancer samples than in normal mucosa. Moreover, SMARCA5 promoter methylation was associated with the absence of protein expression. Our findings suggest that SMARCA5 has a potential role in proliferation and malignancy in gastric carcinogenesis.

PPARα polymorphisms as risk factors for dyslipidemia in a Brazilian population

BACKGROUND AND AIMS

Peroxisome proliferator-activated receptor α is a nuclear receptor involved in the regulation of several biochemical pathways. Polymorphisms within its gene have been associated with several metabolic traits. We aimed to investigate the association of L162V and Intron 7G>C polymorphisms with serum level markers and common morbidities affecting an older adult/elderly cohort from Cuiaba City, Mato Grosso State, Brazil, as well as to compare the results with a previously studied population from São Paulo City, Brazil.

METHODS AND RESULTS

The studied population consisted of 570 subjects from Cuiaba City, Brazil, who were subjected to clinical interviews and blood collection for laboratory examinations and DNA extraction. Dyslipidemia was defined when participants were taking oral hypolipemiants or those with total cholesterol above 200mg/dL, HDL-c below 40 mg/dL, LDL-c above 130 mg/dL and TG above 150 mg/dL. Restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR) was used for polymorphism genotyping. Individual polymorphism and haplotype data were available for analyses. In the studied sample, allele frequencies were 0.052 and 0.292 for 162V and Intron 7C, respectively. In brief, 162V allele was associated with dyslipidemia (p=0.025), and after correction for alcohol consumption and waist-to-rip ratio, a tendency of association could still be observed (p=0.050). In addition, Intron 7C allele was associated with dyslipidemia even after correction for the same variables (p=0.029). When compared to our previous study from São Paulo, we found some divergences regarding these results, which may be explained by differences between the two populations. Haplotype association analyses revealed an association between L/C haplotype and dyslipidemia (p=0.021) and between V/C haplotype and lower LDL-c levels when compared to L/G haplotype (p=0.044).

CONCLUSION

These results may help to clarify the role of PPARα gene in lipid and lipoprotein metabolism and the evaluation of its polymorphisms and haplotypes as being characterized as genetic risk factors for metabolic disturbances.

Cytogenetic molecular delineation of a terminal 18q deletion suggesting neo-telomere formation

Deletion of the long arm of chromosome 18 is one of the most common segmental aneusomies compatible with life and usually involves a deletion of the terminal chromosomal region. However, the mechanisms implicated in the stabilization of terminal deletions are not well understood. In this study, we analyzed a girl with moderate mental retardation who had a cytogenetically visible terminal 18q deletion. In order to characterize the breakpoint in the terminal 18q region, we used fluorescence In situ hybridization (FISH) with bacterial artificial chromosomes (BACs) and pan-telomeric probes and also the array technique based on comparative genomic hybridization (array-CGH). FISH with pan-telomeric probes revealed no signal in the terminal region of the deleted chromosome, indicating the absence of normal telomere repeat (TTAGGG)n sequences in 18q. We suggest that neo-telomere formation by chromosome healing was involved in the repair and stabilization of this terminal deletion.

Insulin-like growth factor binding protein-3 gene methylation and protein expression in gastric adenocarcinoma

OBJECTIVE

The aim of this study was to evaluate IGFBP-3 protein expression, its correlation with gene promoter methylation pattern in gastric carcinogenesis and with clinicopathological characteristics.

DESIGN

Forty-three normal gastric mucosa and 94 adenocarcinoma samples were investigated through methylation specific PCR, after bisulfite modification. Immunohistochemistry was analyzed using peroxidase in 54 gastric cancer and 20 normal gastric mucosa samples.

RESULTS

IGFBP-3 expression was higher in tumor samples than in normal mucosa (p<0.0001). Intestinal type presented a higher frequency of protein expression than diffuse type (p=0.0412). Methylation frequency of IGFBP-3 promoter in gastric samples revealed, respectively, 95.7% and 97.7% in neoplastic and non-neoplastic samples. The frequency of IGFBP-3 methylation did not differ between tumor and normal samples (95.7% versus 97.7%, p=0.7810). We did not observe a significant correlation between IGFBP-3 promoter methylation and protein expression.

CONCLUSION

In summary, our study did not observe any influence of IGFBP-3 promoter methylation on protein expression. Moreover we propose that IGFBP-3 immunostaining in gastric tissue may be a useful marker for malignancy.

Lymphocyte proliferation stimulated by activated human macrophages treated with Canova

INTRODUCTION

Canova (CA) is a homeopathic medication with immunomodulatory properties, recommended for patients with a depressed immune system. CA has been reported to increase in leukocyte numbers, cellular differentiation and reduction in tumor size.

AIM AND METHOD

Since CA may stimulate lymphocyte differentiation, proliferation, and/or survival, the aim of the present study was to compare the mitotic index (MI) of phytohemagglutinin-stimulated human lymphocytes cultured in a medium supplemented with human macrophages activated by CA, with lymphocytes cultured in a medium without CA-treated macrophages.

RESULTS

In this study, the MI of lymphocyte cultured received the medium containing CA-stimulated macrophages showed a higher proliferation index (p<0.01) than the lymphocytes cultured in a medium without CA-treated macrophages. Our results suggest that CA treatment, in addition to activating macrophages, indirectly induces lymphocyte proliferation and has potential as a new adjuvant therapeutic approach.

Genotoxic effects of rotenone on cultured lymphocytes

Rotenone is a heterocyclic compound widely used as an insecticide, acaricide and piscicide. Its toxicity is mainly caused by the inhibition of mitochondrial respiratory processes and ATP production, resulting in the generation of reactive oxygen species. Reactive oxygen species can interact with DNA, RNA and proteins, leading to cell damage, followed by death. We used the Comet assay, and we analyzed chromosome aberrations, in order to evaluate the genotoxic and clastogenic effects of rotenone on the different phases of the cell cycle. Cultured human lymphocytes were treated with 1.0, 1.5 and 2.0 microg/mL rotenone during the G1, G1/S, S (pulses of 1 and 6 h), and G2 phases of the cell cycle. Rotenone induced DNA damage and was clastogenic, but the clastogenicity was detected only with treatments conducted during the G1/S and S phases of the cell cycle. Rotenone also induced endoreduplication and polyploidy in treatments made during G1, while it significantly reduced the mitotic index in all phases of the cell cycle.

Artigo de revisão: diagnóstico cromosômico em rabdomiossarcoma

Os rabdomiossarcomas (RMS) são considerados tumores clinicamente agressivos com origem a partir de células mesenquimais imaturas e que se caracterizam pela presença de células com diferenciação pouco definida. O emprego das técnicas citogenéticas convencionais em RMS vem contribuindo consideravelmente para a diferenciação entre os rabdomiossarcomas alveolares e os outros tumores de células pequenas e redondas, além de fornecer informações prognósticas importantes referente ao rabdomiossarcoma do tipo alveolar. Assim, este trabalho visa a realizar uma revisão das alterações citogenéticas observadas nos diferentes subtipos histológicos de RMS, enfocando não só os trabalhos de citogenética convencional, mas também novas abordagens utilizadas para o estudo de neoplasias tais como FISH, CGH, SKY e M-FISH. Tais metodologias vêm contribuindo de maneira significativa para a melhor compreensão da heterogeneidade cariotípica observada nos RMS.