RESUMO
Small cell lung cancer (SCLC) is a recalcitrant malignancy with dismal prognosis due to rapid relapse after an initial treatment response. More effective treatments for SCLC are desperately needed. Our previous studies showed that cell migration-inducing hyaluronan binding protein (CEMIP) functionally promotes SCLC cell proliferation and metastasis. In this study, we investigated whether and how CEMIP regulates the chemosensitivity of SCLC. Through the GDSC database, we found that CEMIP expression levels were positively correlated with the IC50 values of several commonly used chemotherapeutic drugs in SCLC cells (cisplatin, gemcitabine, 5-fluorouracil and cyclophosphamide). We demonstrated that overexpression or knockdown of CEMIP in SCLC cells resulted in a notable increase or reduction in the IC50 value of cisplatin or etoposide, respectively. We further revealed that CEMIP functions as an adaptor protein in SCLC cells to interact with SRC and YAP through the 1-177 aa domain and 820-1361 aa domain, respectively, allowing the autophosphorylation of Y416 and activation of SRC, thus facilitating the interaction between YAP and activated SRC, and resulting in increased phosphorylation of Y357, protein stability, nuclear accumulation and transcriptional activation of YAP. Overexpressing SRC or YAP counteracted the CEMIP knockdown-mediated increase in the sensitivity of SCLC cells to cisplatin and etoposide. The combination of the SRC inhibitor dasatinib or the YAP inhibitor verteporfin and cisplatin/etoposide (EP regimen) displayed excellent synergistic antitumor effects on SCLC both in vitro and in vivo. This study demonstrated that targeted therapy against the CEMIP/SRC/YAP complex is a potential strategy for SCLC and provides a rationale for the development of future clinical trials with translational prospects.
RESUMO
Dendrobium huoshanense, a unique species in the genus Orchidaceae, is only found in China and is known as "mihu". Due to the lack of quality control, the use of D. huoshanense in the herbal market has been limited. In this study, methods based on thin-layer chromatography, high-performance liquid chromatography and high-performance liquid chromatography coupled with electrospray ionization multi-stage tandem mass spectrometry were used to identify the flavonoids in D. huoshanense and distinguish this species from other Dendrobium species. Using thin-layer chromatography, a characteristic band was observed for D. huoshanense, and this band was absent from the thin-layer chromatography plates of other Dendrobium species. Then, using high-performance liquid chromatography, nine peaks of flavonoids were observed in the chromatograms of ten batches of D. huoshanense. Ultimately, 22 flavonoids in D. huoshanense were identified by multi-stage tandem mass spectrometry, and 11 of these compounds are being reported from D. huoshanense for the first time. In addition, two compounds both with molecular weights of 710, were identified as being unique to D. huoshanense; one of these compounds, apigenin-6-C-α-L-rhamnosyl-(1â2)-ß-D-glucoside-8-C-α-L-arabinoside, was proven to be responsible for the characteristic thin-layer chromatography band of D. huoshanense. These analysis methods can be applied for the identification and quality control of D. Huoshanense.
Assuntos
Dendrobium/química , Flavonoides/análise , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Dendrobium/classificação , Especificidade da Espécie , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em TandemRESUMO
BACKGROUND: Colorectal cancer (CRC) is a common malignant tumor. Alcohol consumption is positively correlated with CRC malignant metastasis; however, the mechanism is unclear. The interaction between laminin-γ2 (LAMC2) and integrin-ß1 (ITGB1) plays a role in premetastatic niche signaling, which may induce epithelial mesenchymal transformation (EMT) and lead to metastasis. AIM: To investigate the effects of alcohol on CRC metastasis from the molecular mechanism of the premetastatic niche. METHODS: The interaction between LAMC2 and ITGB1 was measured by Duolink assay, and the expression levels of LAMC2, ITGB1 and focal adhesion kinase (FAK), snail, fibronectin, N-cadherin and special AT-rich sequence binding protein 1 (SATB1) were measured by quantitative real-time polymerase chain reaction, immunohistochemistry and western blotting. Interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and IL-6 levels were measured via enzyme-linked immunosorbent assay, histopathological assessment via hematoxylin eosin staining, and determination of aberrant crypt foci via methylene blue. RESULTS: The lymph node metastasis rate was higher in the alcohol group than non-alcohol group. There was a significant increase in interaction signals between LAMC2 and ITGB1, and an increase in phosphorylate-FAK/FAK, snail, fibronectin, N-cadherin and SATB1, whereas E-cadherin was reduced in the alcohol group compared to the non-alcohol group in both animal and clinical samples. Serum IL-1ß, TNF-α and IL-6 were higher in alcohol group than in non-alcohol group. Alcohol may promote CRC metastasis by influencing the molecular mechanism of the premetastatic niche. CONCLUSION: Our study suggests that alcohol promotes EMT-mediated premetastatic niche formation of CRC by activating the early interaction between LAMC2 and ITGB1 and lead to CRC metastasis.