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1.
Int J Biol Sci ; 20(7): 2640-2657, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725843

RESUMO

Esophageal carcinoma is amongst the prevalent malignancies worldwide, characterized by unclear molecular classifications and varying clinical outcomes. The PI3K/AKT/mTOR signaling, one of the frequently perturbed dysregulated pathways in human malignancies, has instigated the development of various inhibitory agents targeting this pathway, but many ESCC patients exhibit intrinsic or adaptive resistance to these inhibitors. Here, we aim to explore the reasons for the insensitivity of ESCC patients to mTOR inhibitors. We assessed the sensitivity to rapamycin in various ESCC cell lines by determining their respective IC50 values and found that cells with a low level of HMGA1 were more tolerant to rapamycin. Subsequent experiments have supported this finding. Through a transcriptome sequencing, we identified a crucial downstream effector of HMGA1, FKBP12, and found that FKBP12 was necessary for HMGA1-induced cell sensitivity to rapamycin. HMGA1 interacted with ETS1, and facilitated the transcription of FKBP12. Finally, we validated this regulatory axis in in vivo experiments, where HMGA1 deficiency in transplanted tumors rendered them resistance to rapamycin. Therefore, we speculate that mTOR inhibitor therapy for individuals exhibiting a reduced level of HMGA1 or FKBP12 may not work. Conversely, individuals exhibiting an elevated level of HMGA1 or FKBP12 are more suitable candidates for mTOR inhibitor treatment.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Proteína HMGA1a , Inibidores de MTOR , Proteína Proto-Oncogênica c-ets-1 , Proteína 1A de Ligação a Tacrolimo , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Proteína HMGA1a/metabolismo , Proteína HMGA1a/genética , Camundongos Nus , Inibidores de MTOR/farmacologia , Inibidores de MTOR/uso terapêutico , Proteína Proto-Oncogênica c-ets-1/metabolismo , Proteína Proto-Oncogênica c-ets-1/genética , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Proteína 1A de Ligação a Tacrolimo/metabolismo , Proteína 1A de Ligação a Tacrolimo/genética , Serina-Treonina Quinases TOR/metabolismo
2.
Gut Microbes ; 15(2): 2293312, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38087436

RESUMO

Intestinal dysbiosis frequently occurs in abdominal radiotherapy and contributes to irradiation (IR)-induced intestinal damage and inflammation. Akkermansia muciniphila (A. muciniphila) is a recently characterized probiotic, which is critical for maintaining the dynamics of the intestinal mucus layer and preserving intestinal microbiota homeostasis. However, the role of A. muciniphila in the alleviation of radiation enteritis remains unknown. In this study, we reported that the abundance of A. muciniphila was markedly reduced in the intestines of mice exposed to abdominal IR and in the feces of patients who received abdominal radiotherapy. Abundance of A. muciniphila in feces of radiotherapy patients was negatively correlated with the duration of diarrhea in patients. Administration of A. muciniphila substantially mitigated IR-induced intestinal damage and prevented mouse death. Analyzing the metabolic products of A. muciniphila revealed that propionic acid, a short-chain fatty acid secreted by the microbe, mediated the radioprotective effect. We further demonstrated that propionic acid bound to G-protein coupled receptor 43 (GRP43) on the surface of intestinal epithelia and increased histone acetylation and hence enhanced the expression of tight junction proteins occludin and ZO-1 and elevated the level of mucins, leading to enhanced integrity of intestinal epithelial barrier and reduced radiation-induced intestinal damage. Metformin, a first-line agent for the treatment of type II diabetes, promoted intestinal epithelial barrier integrity and reduced radiation intestinal damage through increasing the abundance of A. muciniphila. Together, our results demonstrated that A. muciniphila plays a critical role in the reduction of abdominal IR-induced intestinal damage. Application of probiotics or their regulators, such as metformin, could be an effective treatment for the protection of radiation exposure-damaged intestine.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Metformina , Humanos , Camundongos , Animais , Intestinos , Verrucomicrobia/metabolismo
3.
Oncogene ; 41(5): 692-703, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34819634

RESUMO

N6-methyladenosine (m6A), the most abundant mRNA modification in mammals, is involved in the metabolism of mRNA. KIAA1429 is regarded as the largest m6A methyltransferase and plays an important role in m6A modification. However, the prognostic value and function of KIAA1429 in colorectal cancer (CRC) are unclear. Quantitative real-time PCR and immunohistochemical assays were performed to evaluate the expression of KIAA1429 in CRC tissues. Kaplan-Meier survival curves and log-rank tests were used to assess the association between KIAA1429 expression and the prognosis of patients with CRC. CCK-8 assays, colony formation assays, cell cycle assays, and xenograft experiments were performed to investigate the effect of KIAA1429 on cell proliferation. RNA immunoprecipitation, methylated RNA immunoprecipitation assays, and RNA stability assays were conducted to explore the underlying mechanism. KIAA1429 was significantly upregulated in CRC tissues compared with adjacent normal tissues. Patients with higher expression of KIAA1429 had shorter overall survival than those with lower expression. Functionally, KIAA1429 promoted CRC cell proliferation in vitro and in vivo. Mechanistically, KIAA1429 negatively regulated the expression of WEE1 by decreasing its stability in an m6A-independent manner by binding to the third segment in the 3'-UTR of WEE1 mRNA. Moreover, butyrate decreased the expression of KIAA1429 by downregulating the level of the transcription factor NFκB1. Our findings indicated that KIAA1429 plays an oncogenic role in CRC cells by inhibiting the expression of WEE1 in an m6A-independent manner and is associated with poor survival in CRC patients. These results suggested that KIAA1429 might be a potential prognostic marker for CRC.


Assuntos
Oncogenes
5.
Mater Sci Eng C Mater Biol Appl ; 96: 635-641, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30606575

RESUMO

Cisplatin is a highly effective antitumor drug, which can kill cancer cells by crossing-linking DNA and inhibiting transcription, but this process is limited by the combination of cisplatin and many endogenous nucleophiles, such as glutathione (GSH). Thus, when cisplatin enter cells, it is potentially vulnerable to cytoplasmic inactivation by GSH. To settle this bottleneck, we designed and synthesized a probe compound (Probe 1) and fabricated pH-responsed cisplatin, Probe 1-loaded lipid-polymer hybrid NanoParticles (CPNPs) using a single-step sonication method. Probe 1 can specifically bind to GSH, thus avoiding the combination of GSH and cisplatin, and enhancing the pharmacological activity of cisplatin. In vitro studies have suggested CPNPs, compared with cisplatin, loaded lipid-polymer hybrid NanoParticles CNPs (Not contain Probe 1), could efficiently kill MCF-7 human breast cancer cells and A549 human nonsmall lung cancer cell. Hence, the CPNPs provided a new idea for treating cancer.


Assuntos
Neoplasias da Mama , Cisplatino , Glutationa/metabolismo , Neoplasias Pulmonares , Nanopartículas , Células A549 , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Cisplatino/química , Cisplatino/farmacocinética , Cisplatino/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Células MCF-7 , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Sondas Moleculares/farmacologia , Nanopartículas/química , Nanopartículas/uso terapêutico
6.
J Biomed Res ; 33(3): 173-180, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-30057371

RESUMO

Caspase-8 (CASP8) is one key regulator of apoptosis of T lymphocytes and is encoded by the CASP8 gene. It has been reported that the six-nucleotide deletion polymorphism (-652 6N del) of the CASP8 gene had effect on some cancer risk. Few studies explored the association between CASP8 gene polymorphism and digestive tract cancer risk. To evaluate the association between the CASP8 -652 6N del polymorphism and the risk of digestive tract cancer, we conducted this meta-analysis. We found that CASP8-652 6N del polymorphism was associated with a significantly reduced risk of digestive tract cancer in the co-dominant model (del/del vs. ins/ins: OR= 0.82, 95%CI= 0.72-0.95; del/ins vs. ins/ins: OR= 0.92, 95%CI= 0.87-0.97; dominant model (del/ins+ del/del vs. ins/ins: OR= 0.91, 95%CI= 0.87-0.96, recessive model: del/del vs. del/ins+ ins/ins: OR= 0.85, 95%CI= 0.75-0.97). In the stratified analysis by cancer types, we found that all genetic models had protective effect on gastric cancer. Similar results were observed for colorectal cancer under heterozygote comparison and dominant model, but not under homozygote comparison or recessive model. In addition, a significantly decreased risk was found on esophageal cancer for most genetic models, except heterozygote comparison. When stratified by ethnicity and source of control, an evidently decreased risk was identified in the Asian populations and population-based studies. In conclusion, there exists an association between the CASP8 -652 6N del polymorphism and reduced digestive cancer risk, especially among Asians and population-based studies.

7.
Biomed Pharmacother ; 68(7): 905-10, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25194442

RESUMO

Studies investigating the association between the BRCA1 rs799917 polymorphism and breast cancer risk have reported controversial results. In order to derive a more precise estimation of the relationship, we performed a comprehensive meta-analysis. A total of 8 articles comprising 19,878 subjects were included in this meta-analysis. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated by Stata 11 software. Heterogeneity tests were conducted by Q test with I(2) value, and publication bias assessment was performed by Begg's funnel plot and Egger's test. The pooled results did not show any sufficient evidence approving the association between the BRCA1 rs799917 polymorphism and breast cancer risk in total population (T vs C: OR=1.01, 95% CI=0.97-1.06; TT vs CC: OR=1.03, 95% CI=0.93-1.13; CT vs CC: OR=1.04, 95% CI=0.92-1.16; TT+CT vs CC: OR=1.04, 95% CI=0.94-1.15; TT vs CT+CC: OR=1.03, 95% CI=0.94-1.12). In the further subgroup analyses, no significant associations were found in any comparison models according to ethnicity and source of controls. No publication bias was observed in this meta-analysis. In summary, based on the overall results, this meta-analysis strongly suggests that the BRCA1 rs799917 polymorphism is not associated with breast cancer risk.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Predisposição Genética para Doença/genética , Polimorfismo Genético/genética , Alelos , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Razão de Chances , Fatores de Risco
8.
Biomed Rep ; 1(5): 737-742, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24649020

RESUMO

A C/T polymorphism (rs11614913) was identified in the microRNA (miRNA) 196a2 (miR-196a2) gene and was implicated in the susceptibility to cancer. Numerous studies have investigated its association with the risk of colorectal cancer (CRC). However, the results were inconsistent and inconclusive. The present meta-analysis was conducted based on the results of six published case-control studies comprising 1,754 cases and 2,430 controls (up to November, 2012). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for the allelic and genotypic comparisons following the co-dominant, dominant and recessive genetic models. The Chi-square-based Q-test was used to assess heterogeneity. Egger's test and inverted funnel plots were used to investigate publication bias. Subgroup analysis was also performed. The results demonstrated that almost all the genetic models (except the model of CT vs. TT) indicated a significant association between rs11614913 polymorphism and CRC risk. The subgroup analysis in an Asian population also demonstrated similar results. However, there was no significant association of miR-196a2 rs11614913 polymorphism with the clinical characteristics of CRC patients. Our results confirmed the association of the polymorphism rs11614913 with the risk of CRC, but not with tumor stage and grade.

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