Autophagy Flux Contributes to Regulation of Components of Eclipta prostrata L. on Cigarette Smoking-Induced Injury of Bronchial Epithelial Cells

Development and Validation of an Autophagy-Related LncRNA Prognostic Signature in Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is one of the greatest public challenges because of delayed diagnosis and poor prognosis. In this study, we established an autophagy-associated long non-coding (Lnc)RNA prognostic signature to assess the prognosis of HNSCC patients. The LncRNA expression profiles and clinical information of 499 HNSCC samples were available in The Cancer Genome Atlas. Autophagic LncRNAs were analyzed using Pearson correlation. A co-expression network showed the interactions between autophagic genes and LncRNAs. An autophagic LncRNAs prognostic signature, consisting of MYOSLID, AL139287.1, AC068580.1, AL022328.2, AC104083.1, AL160006.1, AC116914.2, LINC00958, and AL450992.2, was developed through uni- and multivariate Cox regressions. High- and low-risk groups were classified based on the median risk scores. The high-risk group had significantly worse overall survival according to Kaplan–Meier curve analysis. Multivariate Cox regression demonstrated that risk scores were a significant independent prognostic factor (hazard ratio = 1.739, 95% confidence interval: 1.460–2.072), with an area under the curve of 0.735. Principal component analysis distinguished two categories based on the nine-LncRNA prognostic signature. In conclusion, this novel autophagic LncRNA signature is an independent prognostic factor and may suggest novel therapeutic targets for HNSCC.

Chinese herbal medicine Feiyanning cooperates with cisplatin to enhance cytotoxicity to non-small-cell lung cancer by inhibiting protective autophagy

ETHNOPHARMACOLOGICAL RELEVANCE

Feiyanning (FYN), the Chinese herbal medicine (CHM), has been used to manage non-small cell lung cancer (NSCLC) for the past 23 years. Chemotherapeutic drugs can induce autophagy in cancer cells to protect themselves from death. However, FYN can inhibit the protective autophagy in cancer cells. We investigated the biological mechanisms on the synergistic effects of FYN combined with chemotherapy in lung cancer cells.

MATERIALS AND METHODS

We analyzed the effective chemical components for the quality control of FYN using the UPLC-Q-TOF-MS.The cell proliferation ability was detected by the cell counting kit-8 (CCK-8) and colony formation. The cell apoptosis was determined with Flow cytometry. Expression of important differential proteins were detected by western blot. Autophagy structure was observed by TEM (Tansmission electron microscopy). Tandem mCherry-EGFP-LC3B immunofluorescence was used to measure autophagic flux.

RESULTS

Both FYN and cisplatin significantly induced apoptosis and inhibited cell proliferation in A549 cells. FYN reduced cell viability and increased apoptotic cell populations less effectively than cisplatin. FYN cooperated with cisplatin suppressed the cell viability, colony formation, as well as increased the cell apoptosis rate, and the expression of cleaved caspase-3 and PARP. FYN inhibited autophagy in A549 cells, which characterized by the decrease of autophagosome formation, lysosomal fusion, LC3B-II accumulation and SQSTM1 degradation, down-regulation of ATG5 and ATG7. Protective autophagy in A549 cells was induced by cisplatin. Suppression of the autophagic response using chloroquine (CQ) which is autophagy inhibitor improved the ability of cisplatin to kill cancer cells, as did FYN combined with cisplatin.

CONCLUSION

In summary, we revealed that the synergistic mechanism of FYN and cisplatin is that FYN inhibited the protective autophagy induced by cisplatin in A549 cells.

In vitro study of the role of FOXO transcription factors in regulating cigarette smoke extract-induced autophagy

Cigarette smoking is the chief etiological factor for chronic obstructive pulmonary disease (COPD). Oxidative stress induced by cigarette smoke (CS) causes protein degradation, DNA damage, and cell death, thereby resulting in acute lung injury (ALI). In this regard, autophagy plays a critical role in regulating inflammatory responses by maintaining protein and organelle homeostasis and cellular viability. Expression of autophagy-related proteins (ARPs) is regulated by the fork head box class O (FOXO) transcription factors. In the current study, we examined the role of FOXO family proteins-FOXO1 and FOXO3a-in regulating CS extract (CSE)-induced autophagy. Using human lung adenocarcinoma cells with type II alveolar epithelial characteristics (A549), we observed CSE-mediated downregulation of FOXO3a. In contrast, there was a pronounced increase in the expression of FOXO1 at both the transcriptional and translational levels in the CSE-challenged cells compared with controls. Interestingly, knockdown of FOXO3a heightened the CSE-mediated increase in expression of cytokines/chemokines (IL-6, IL-8, and MCP-1), ARPs, and the FOXO1 transcription factor. Moreover, FOXO1 knockdown rescued CSE-mediated upregulation of ARPs in A549 cells. In addition, using the ROS inhibitor N-acetyl-L-cysteine (NAC), we observed abrogated mRNA expression of several ARPs and production of inflammatory cytokines/chemokines (IL-6, IL-8, MCP-1, and CCL-5) in the CSE-challenged cells suggesting an important role of ROS in regulating CSE-induced autophagy. Chromatin immunoprecipitation of FOXO1 and FOXO3a demonstrated increased binding of the former to promoter regions of autophagy genes- BECLIN1, ATG5, ATG12, ATG16, and LC3 in CSE challenged cells. These findings suggest the role of FOXO1 in regulating the expression of these genes during CSE exposure. Overall, our findings provide evidence for FOXO3a-dependent FOXO1-mediated regulation of autophagy in the CSE-challenged cells. Graphical abstract.

A review on traditional uses, phytochemistry and pharmacology of Eclipta prostrata (L.) L

ETHNOPHARMACOLOGICAL RELEVANCE

Eclipta prostrata, a traditional herbal medicine, has long been used in Asia and South America for the therapy of hemorrhagic diseases (e.g. hemoptysis, hematemesis, hematuria, epistaxis and uterine bleeding), skin diseases, respiratory disorders, coronary heart disease, hair loss, vitiligo, snake bite and those caused by the deficiency of liver and kidney.

AIM OF THE REVIEW

In this review, we highlight relatively comprehensive and up-to-date information of E. prostrata on traditional uses, phytochemistry, pharmacology and toxicity, along with featuring the gaps in current knowledge, aiming to provide references for future research and possible opportunities for well applications of this medicinal plant.

MATERIALS AND METHODS

Information on E. prostrata was gathered from scientific databases (Google Scholar, Web of Science, Scifinder, Baidu Scholar, PubMed and CNKI). Information was also obtained from local books, Ph.D. theses and M.Sc. dissertations and Chinese Pharmacopoeia. The plant taxonomy was validated by the database "The Plant List".

RESULTS

Various phytochemical classes has been identified and isolated from the plant covering triterpenes, flavonoids, thiopenes, coumestans, steroids and others. Among these, coumestans are reported as the most common ingredients. The isolated crude extracts and individual compounds have been reported to exhibit promising pharmacological properties, such as hepatoprotective, osteoprotective, cytotoxic, hypoglycaemic, anti-inflammatory, anti-microbial, hypolipidemic, promoting hair growth, rejuvenative and neuroprotective effects.

CONCLUSIONS

Until now, significant progress has been witnessed in phytochemistry and pharmacology of E. prostrata. Thus, some traditional uses has been well supported and clarified by modern pharmacological studies. Moreover, E. prostrata also showed therapeutic potential in some refractory diseases such as cancer, dementia and diabetes. But, present findings are still insufficient that cannot satisfactorily explain some mechanisms of action. More well-designed studies in vitro especially in vivo are required to establish links between the traditional uses and bioactivities, discover new skeletons and activity molecules, as well as ensure safety before clinical use.

Antimetastatic effects of Eclipta prostrata extract on oral cancer cells

Eclipta prostrata, a traditional Chinese medication, has been used for the treatment of several diseases. However, the molecular mechanism underlying the effects of Eclipta prostrata extracts (EPE) on human oral cancer cell metastasis remains unclear. We thus examined the effects of EPE on metastasis promoting proteins in oral cancer. Our results revealed that the EPE attenuated SCC-9, HSC-3, and TW2.6 cell migration and invasiveness by reducing matrix metalloproteinase (MMP)-2 enzyme activities. In addition, Western blot analysis revealed that EPE significantly reduced the levels of phosphorylated extracellular signal-regulated kinase 1/2 (ERK 1/2) but not those of c-Jun N-terminal kinase (JNK) 1/2 and p38. In conclusion, we found that EPE could inhibit oral cancer metastasis through the inhibition of MMP-2 expression. Therefore, EPE may be used to prevent the metastasis of oral cancer, and has the potential to be applied to cancer treatment.