[The zebrafish model in oncology]

Integrating Network Pharmacology and Experimental Validation to Explore the Effects and Mechanisms of Qinghao Biejia Decoction and Its Active Compound Artemisinin B Against Non-Small-Cell Lung Cancer

Purpose

To explore the pharmacological effects and mechanisms of Qinghao Biejia decoction (QBD) against non-small-cell lung cancer (NSCLC) based on network pharmacology and to verify the anticancer effect of artemisinin B (ART B), the active ingredient of QBD, on H1299 cells.

Methods

Ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) was applied to explore the chemoprofile of QBD. A zebrafish xenograft model was used to determine the anti-cancer efficacy of QBD. Cell counting kit-8 assay, terminal deoxyribonucleotide transferase-mediated-dUTP nick-end labeling assay; immunofluorescence, and flow cytometry were used to evaluate the in vitro anti-proliferative and pro-apoptotic effects of QBD and ART B on H1299 cells. Subsequently, the related targets and action mechanisms of both QBD and ART B predicted by network pharmacological analyses were experimentally validated by real-time PCR and Western blot assays on H1299 cells.

Results

UPLC-QTOF-MS/MS identified a total of 69 compounds (such as ART B, mangiferin, and artemisinic acid) in QBD. The in vivo data showed that QBD significantly inhibited the growth of H1299 cells in xenograft larval zebrafish from 125 to 500 μg/mL. The in vitro data showed that QBD induced apoptosis of H1299 cells, accompanied by down-regulating the expression of BCL-2 and up-regulating the expression of BIM, PUMA, BAX, c-PARP, γ-H2A.X, c-CASP3, and c-CASP8. Alike QBD, ART B exerted similar anti-proliferative and pro-apoptotic effects on H1299 cells. Moreover, ART B inhibited expressions of BCL2L1, AKT1, AKT2, MMP-2, and EGFR, and up-regulated ALB expression. Mechanistically, ART B promoted apoptosis of H1299 cells by inhibiting PI3K/Akt signaling pathway.

Conclusion

This study revealed the anti-NSCLC efficacy of QBD. ART B, the effective component of QBD, plays an anti-NSCLC role by down-regulating the PI3K-Akt signaling pathway. It suggests that QBD and ART B are promising drug candidates for NSCLC treatment.

Zebrafish xenograft model for studying mechanism and treatment of non-small cell lung cancer brain metastasis

Background

Brain metastasis (BM) is thought to be related to the mortality and poor prognosis of non-small cell lung cancer (NSCLC). Despite promising development of NSCLC treatment, the treatment of NSCLC BM is still not optimistic due to the existence of the blood-brain barrier (BBB) that prevent drug penetration, as well as the short median survival time of the patients left for treatment. In this context, further development of quick and effective pre-clinical models is needed in NSCLC BM treatment. Here, we report a model system using zebrafish to promote the development of drugs for patients with NSCLC BM.

Methods

Three different NSCLC cell lines (H1975, A549 and H1299) were used to establish zebrafish BM models. The embryo age and cell number for injection were first optimized. Metastatic cells were observed in the brain blood vessels of zebrafish and were verified by hematoxylin-eosin (HE) staining. Then, the metastasis potentials of H1975 and A549 with manipulated microRNA-330-3p (miR-330-3p) expression were also investigated. Finally, sensitivities of H1975 and A549 to osimertinib and gefitinib were tested.

Results

This zebrafish BM model could distinguish NSCLC cell lines with different BM potential. Over-expressed miR-330-p significantly improved the BM potential of the A549 cells while knockdown miR-330-p reduced the BM ability of the H1975 cells. Both osimertinib and gefitinib showed inhibition effect in zebrafish BM model with the inhibition rate higher than 50 %. H1975 cell showed much higher sensitivity to osimertinib rather than gefitinib both in vivo and in vitro.

Conclusions

We established zebrafish brain metastasis model for studying mechanism and treatment of NSCLC BM. This study provided a useful model for NSCLC brain metastasis that could be used to study the mechanism that drive NSCLC cells to the brain as well as identify potential therapeutic options.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02173-5.

Pseudocapillaria tomentosa, Mycoplasma spp., and Intestinal Lesions in Experimentally Infected Zebrafish Danio rerio

Intestinal neoplasms and preneoplastic lesions are common in zebrafish research facilities. Previous studies have demonstrated that these neoplasms are caused by a transmissible agent, and two candidate agents have been implicated: a Mycoplasma sp. related to Mycoplasma penetrans and the intestinal parasitic nematode, Pseudocapillaria tomentosa, and both agents are common in zebrafish facilities. To elucidate the role of these two agents in the occurrence and severity of neoplasia and other intestinal lesions, we conducted two experimental inoculation studies. Exposed fish were examined at various time points over an 8-month period for intestinal histopathologic changes and the burden of Mycoplasma and nematodes. Fish exposed to Mycoplasma sp. isolated from zebrafish were associated with preneoplastic lesions. Fish exposed to the nematode alone or with the Mycoplasma isolate developed severe lesions and neoplasms. Both inflammation and neoplasm scores were associated with an increase in Mycoplasma burden. These results support the conclusions that P. tomentosa is a strong promoter of intestinal neoplasms in zebrafish and that Mycoplasma alone can also cause intestinal lesions and accelerate cancer development in the context of nematode infection.

Morphological Abnormalities and Gene Expression Changes Caused by High Incubation Temperatures in Zebrafish Xenografts with Human Cancer Cells

Published studies show that most of the human cancer xenograft studies in zebrafish embryos have used incubation temperatures in the range of 32–34 °C for 3–6 days post-injection, trying to find a compromise temperature between the zebrafish embryos (28 °C) and the human injected cells (37 °C). While this experimental setup is widely used, a question remains: is possible to overcome the drawbacks caused by a suboptimal temperature for the injected cells? To clarify the effect of temperature and injected cells on the host, in this study, we analyzed the development and health of the last in response to different temperatures in the presence or absence of injected human cancer cells. Comparing different incubation temperatures (28, 34 and 36 °C), we determined morphological abnormalities and developmental effects in injected and non-injected embryos at different time points. Besides this, the expression of selected genes was determined by qPCR to determine temperature affected metabolic processes in the embryos. The results indicate that an incubation temperature of 36 °C during a period of 48 h is suitable for xenotransplantation without morphological or metabolic changes that could be affecting the host or the injected cells, allowing them to proliferate near their optimal temperature.

[Cutaneous melanoma: from rationalized models to patients care]

Cutaneous melanoma derives from the tumoral transformation of melanocytes. These pigmented cells produce melanin prior transmitting it to the surrounding keratinocytes of the skin, hair and mane. The main function of melanin is to protect cells and their DNA from damage caused by ultraviolet light. Melanoma is the most aggressive skin cancer whose incidence has increased steadily in recent decades. Advances in basic research have resulted in a better understanding of the molecular and cellular events responsible for the initiation and progression of melanomas. In this review, we present an overview of the knowledge gained in recent years and show how recent advances lead to new targeted and more efficient therapeutic approaches.