Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Cell Mol Gastroenterol Hepatol ; 14(5): 1053-1076, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35944892

RESUMO

BACKGROUND & AIMS: Long noncoding RNAs (lncRNAs) are found to have profound impacts on diverse cellular processes. Although high-throughput sequencing studies have shown the differential lncRNA expression profiles between hepatocellular carcinoma (HCC) and nontumor livers, the functional impacts of lncRNAs on HCC development await further investigation. Herein, we sought to address the functional roles of lncRNAs in HCC pathogenesis by in vivo functional screening. METHODS: We performed genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)/dead CRISPR-associated protein 9 (dCas9) lncRNA activation screening in HCC xenografts. We characterized the clinical relevance of positively selected lncRNAs using transcriptomic data sets. We used CRISPR-based gene activation and knockdown approaches to show the functional roles of positively selected lncRNAs including Cancer Susceptibility 11 (CASC11) in HCC. RNA sequencing and chromatin isolation by RNA purification sequencing were used to investigate the molecular mechanisms of CASC11 in HCC progression. RESULTS: The in vivo functional screening identified 1603 positively selected lncRNAs, 538 of which were overexpressed in HCC patients. Systematic transcriptomic data analysis and clinical investigation showed that patients with high expression of these lncRNA candidates correlated with aggressive tumor behaviors. Overexpression of these lncRNAs aggravated HCC cell growth. Detailed characterization of a lncRNA candidate, CASC11, showed its pivotal role in cell proliferation and tumor growth. Mechanistically, chromatin isolation by RNA purification sequencing showed that CASC11 was bound to the CASC11/MYC proto-oncogene shared promoter region on chromosome 8q24. CASC11 modulated the transcriptional activity of MYC in a cis-regulatory manner, which affected the expression of MYC downstream target genes, consequently promoting G1/S progression. CONCLUSIONS: Our study showed the power of in vivo CRISPR screening, which comprehensively investigated the functionality of lncRNAs in HCC progression, providing a rationale for targeting these lncRNAs clinically.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Humanos , Carcinoma Hepatocelular/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias Hepáticas/patologia , Proteína 9 Associada à CRISPR/genética , Cromatina
2.
Int J Mol Sci ; 22(6)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808647

RESUMO

Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies worldwide. HCC is associated with several etiological factors, including HBV/HCV infections, cirrhosis, and fatty liver diseases. However, the molecular mechanism underlying HCC development remains largely elusive. The advent of high-throughput sequencing has unveiled an unprecedented discovery of a plethora of long noncoding RNAs (lncRNAs). Despite the lack of coding capacity, lncRNAs have key roles in gene regulation through interacting with various biomolecules. It is increasingly evident that the dysregulation of lncRNAs is inextricably linked to HCC cancer phenotypes, suggesting that lncRNAs are potential prognostic markers and therapeutic targets. In light of the emerging research in the study of the regulatory roles of lncRNAs in HCC, we discuss the association of lncRNAs with HCC. We link the biological processes influenced by lncRNAs to cancer hallmarks in HCC and describe the associated functional mechanisms. This review sheds light on future research directions, including the potential therapeutic applications of lncRNAs.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular/genética , Suscetibilidade a Doenças , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , RNA Longo não Codificante , Animais , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/terapia , Transformação Celular Neoplásica/genética , Gerenciamento Clínico , Genes Supressores de Tumor , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Técnicas de Diagnóstico Molecular , Terapia de Alvo Molecular , Oncogenes , Transdução de Sinais/efeitos dos fármacos
3.
Front Pharmacol ; 10: 706, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293425

RESUMO

Angelica sinensis (AS, Danggui) has long been regarded to stimulate breast cancer growth; hence, the use of AS in breast cancer patients remains a major concern for both patients and practitioners. Since safety studies of herbs would be unethical to carry out in patients, the present study aimed to investigate the potential unsafe effects of AS in a systematic pre-clinical approach. Human breast cancer cells, breast orthotopic tumor-bearing mouse models, as well as primary breast cancer cells from patients' tumors were used to evaluate the effect of AS hot water extract on the progression of breast tumors and/or growth of breast cancer cells. We showed that AS is not that stimulatory in breast cancer both in vitro and in vivo, though AS should still be used with caution in estrogen receptor-positive breast cancer patients. This novel approach of applying breast cancer cell lines, xenograft, and syngeneic tumors models, as well as primary breast cancer cells from patients' tumors in Chinese medicines safety evaluation was proven feasible. Our finding is important information for patients, Chinese medicine practitioners, and clinicians on the safety use of AS in breast cancer, which will affect future clinical practice.

4.
J Tradit Complement Med ; 9(3): 179-183, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31193936

RESUMO

Quality surveillance on authentication, safety and efficacy of proprietary Chinese medicines (pCm) are certainly the top priorities for the industries. Nowadays, the quality control system adopted is mainly chemical marker-oriented, concerning basically the correct use of raw material and safety issues, while the biological activities of the chemical marker(s) are seldom considered. Hence, there is an undefined relationship between the amount of chemical markers and the claimed pharmacological activities. In view of the need in identifying appropriate markers for biological standardization of pCm products, the present study aimed to establish a systematic methodology for verifying whether the chemical marker of a traditional Chinese medicine (TCM) listed in Chinese Pharmacopoeia could be upgraded to a bioactive marker with certain efficacy in treating a particular disease. Our proposed methodology included a series of work on extraction, quantification, literature search and in vivo pharmacological experiments, in which the water extractability, biological effects at theoretical dose and oral bioavailability of the candidate chemical markers were all taken into consideration. The feasibility and implication of this bioactive markers verification methodology were further elaborated. Our findings will serve as the foundation for further research and development of biological standardization of TCM.

5.
Phytomedicine ; 56: 103-117, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30668331

RESUMO

BACKGROUND: An increasing number of breast cancer patients in Asian countries has been found to consume dietary supplements including phytoestrogen-rich Chinese herbal medicines with an expectation to alleviate the side effects of conventional cancer therapies. PURPOSE: The question of whether estrogenic Chinese herbal medicines are beneficial or detrimental to the health of breast cancer patients remains uncertain. STUDY DESIGN: The present study aimed at establishing a systematic approach to look at the safety profiles of estrogenic Chinese herbal medicines (CHM). METHODS: The effects of estrogenic CHM on the growth of human breast cancer cells as well as the progression of breast tumors in mice have been investigated. RESULTS: Our results demonstrated that among 10 selected estrogenic CHM, the aqueous extracts of Cistanche deserticola (CD) and Dioscorea opposita (DO) at 0.4 to 1.6 mg/ml significantly stimulated cell viability in both estrogen receptor (ER)-positive (MDA-MB-361 and MCF-7) and ER-negative (SKBR3 and MDA-MB-231) breast cancer cells. However, results from animal studies showed that no significant difference was found on the size of mouse 4T1 breast tumors in CD- and DO-treated mice when compared with the control group, while the number of proliferative cells were found to be increased in DO-treated group. Besides, CD and DO treatments induced significant immunomodulatory effects on 4T1 tumor-bearing mice by increasing the production of cytokines IL-2 and IFN-γ and modulation of regulatory T-cells. Furthermore, CD and DO treatments did not stimulate, but in fact suppressed human triple-negative MDA-MB-231 breast xenografts growth in immunodeficiency mice. CONCLUSION: The considerable concerns on the use of CD and DO in breast cancer patients could be relieved to some extents upon the findings of this pre-clinical study. The potential harmful effects of estrogenic Chinese herbal medicines on breast cancer growth should be verified in both cell-based and tumor-bearing mice models.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cistanche/química , Dioscorea/química , Medicamentos de Ervas Chinesas/efeitos adversos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos SCID , Fitoestrógenos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...