RESUMO
INTRODUCTION: Gastric cancer (GC) remains a common health concern worldwide and is the third leading cause of death in Japan. It can be broadly classified into gastric and intestinal mucin phenotypes using immunohistochemistry. We previously reported numerous associations of kinesin family member (KIF) genes and mucin phenotypes with GC. However, no previous studies have reported on the importance of KIF18B in GC using immunostaining. Thus, in this study, we investigated the expression and functions of KIF18B, which is highly expressed in gastric mucin phenotype GC. METHODS: We performed RNA-seq of gastric and intestinal mucin type GCs, and clinicopathological studies of the KIF18B we found were performed using 96 GC cases. We also performed functional analysis using GC-derived cell lines. RESULT: RNA-seq showed the upregulation of matrisome-associated genes in gastric mucin phenotype GC and a high expression of KIF18B. KIF18B was detected in 52 of the 96 GC cases (54%) through immunohistochemistry. Low KIF18B expression was significantly associated with poor overall survival (p < 0.01). Other molecules that were significantly associated with KIF18B were MUC5AC and claudin 18; these were also significantly associated with the gastric mucin phenotype. KIF18B small interfering RNA (siRNA)-transfected GC cells showed greater growth and spheroid colony formation than the negative control siRNA-transfected cells. Furthermore, expression of snail family transcriptional repressor 1 and cadherin 2 was significantly increased and that of cadherin 1 was significantly decreased in KIF18B siRNA-transfected GC cells. CONCLUSION: These findings not only suggest that KIF18B may be a useful prognostic marker, but also provide insight into the pathogenesis of the GC phenotype.
Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Cinesinas/genética , Cinesinas/metabolismo , Mucinas Gástricas/genética , Mucinas Gástricas/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , RNA Interferente Pequeno , Transição Epitelial-Mesenquimal/genética , Fenótipo , Regulação Neoplásica da Expressão Gênica , Linhagem Celular TumoralRESUMO
As the new platinum drug oxaliplatin has been widely used in clinical treatment of colorectal cancer (CRC), oxaliplatin resistance has become a burning problem. In this study, higher expression of PARP-1 binding protein (PARPBP) was detected in oxaliplatin-resistant CRC (OR-CRC) cells than in non-resistant cells. Further research showed that kinesin family member 18 b (KIF18b) induced the overexpression of PARPBP, sustaining oxaliplatin resistance in OR-CRC cells. Through exploring the PARPBP gene promoter, we found that SP1-recruited DNMT3b methylated PARPBP promoter to suppress transcription in CRC cells, and increased KIF18b attenuated the recruitment of DNMT3b to PARPBP promoter by directly interacting with SP1 in OR-CRC cells. Clinical analysis suggested a positive relationship between KIF18b and PARPBP in CRC tissues and indicated poor prognosis in CRC patients with high level of KIF18b or PARPBP. In summary, KIF18b-induced PARPBP contributes to the resistant phenotype of OR-CRC.
Assuntos
Neoplasias Colorretais/tratamento farmacológico , Metilação de DNA , Proteínas de Ligação a DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Cinesinas/metabolismo , Oxaliplatina/farmacologia , Idoso , Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Humanos , Cinesinas/genética , Masculino , Prognóstico , Regiões Promotoras Genéticas , Taxa de Sobrevida , Células Tumorais CultivadasRESUMO
BACKGROUND: Kinesin family member 18B (KIF18B) has been regarded as an oncogene that is abnormally overexpressed in some cancers, but its mechanism in esophageal squamous cell carcinoma (ESCC) remains unclear, which is thereby investigated in this study. METHODS: Bioinformatics analysis was performed to analyze the expression of KIF18B in esophageal carcinoma (ESCA). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect KIF18B expression in ESCC cells. After KIF18B overexpression or cell division cycle associated 8 (CDCA8) deficiency, ESCC cells were subjected to determination of qRT-PCR, Western blot, cell counting kit-8 assay, flow cytometry, wound healing, and Transwell assay. The mechanism of KIF18B in the mechanistic target of rapamycin complex 1 (mTORC1) pathway was detected by Western blot. RESULTS: KIF18B was overexpressed in ESCA samples and ESCC cells. Upregulation of KIF18B enhanced the viability, accelerated cell cycle by elevating CDK4 and Cyclin D3 levels as well as promoted the migration and invasion by decreasing E-cadherin level and increasing Vimentin and N-cadherin levels in ESCC cells, which was counteracted by CDCA8 silencing. The expression of CDCA8 in ESCC cells was upregulated by KIF18B overexpression. KIF18B overexpression activated the mTORC1 pathway by upregulating phosphorylated (p)-/p70S6K and p-/mTOR levels in the ESCC cells, which was reversed by CDCA8 silencing. CONCLUSION: KIF18B overexpression promotes the proliferation, migration, and invasion of ESCC cells via CDCA8-mediated mTORC1 signaling pathway in vitro.