Study on the Mechanism of Notch Pathway Mediates the Role of Lenvatinib-resistant Hepatocellular Carcinoma Based on Organoids

BACKGROUND

The emergence of treatment resistance has hindered the efficacy of targeted therapies used to treat patients with hepatocellular carcinoma (HCC).

OBJECTIVE

This study aimed to explore the mechanism of organoids constructed from lenvatinib-resistant HCC cells.

METHODS

Hep3B cell and human HCC organoids were cultured and identified using hematoxylin and eosin staining and Immunohistochemistry. Lenvatinib-sensitive/ resistant Hep3B cells were constructed using lenvatinib (0, 0.1, 1, and 10 μM) and lenvatinib (0, 1, 10, and 100 μM). qRT-PCR and flow cytometry were utilized to determine HCC stem cell markers CD44, CD90, and CD133 expressions. Transcriptome sequencing was performed on organoids.-Western blot evaluated Notch pathwayrelated proteins (NOTCH1 and Jagged) expressions. Furthermore, DAPT, an inhibitor of the Notch pathway, was used to investigate the effects of lenvatinib on resistance or stemness in organoids and human HCC tissues.

RESULTS

The organoids were successfully cultivated. With the increase of lenvatinib concentration, sensitive cell organoids were markedly degraded and ATP activity was gradually decreased, while there was no significant change in ATP activity of resistant cell organoids. CD44 expressions were elevated after lenvatinib treatment compared with the control group. KEGG showed that lenvatinib treatment of organoids constructed from Hep3B cells mainly activated the Notch pathway. Compared with the control group, NOTCH1 and Jagged expressions elevated, and ATP activity decreased after lenvatinib treatment. However, ATP activity was notably decreased after DAPT treatment. Moreover, DAPT inhibited lenvatinib resistance and the increase in the expressions of CD44 caused by lenvatinib. Besides, 100 μM lenvatinib significantly inhibited the growth and ATP activity of human HCC organoids, and DAPT increased the inhibitory effect of lenvatinib.

CONCLUSION

Lenvatinib regulated resistance and stemness in organoids via the Notch pathway.

Enhancing the Regenerative Potential of Adipose-Derived Mesenchymal Stem Cells through TLR4-Mediated Signaling

INTRODUCTION

Toll-like receptor 4(TLR4) is a receptor that traditionally plays an important role in immunomodulation (regulation of the immune system) and the initiation of proinflammatory responses. TLR4 is used in the body to recognize molecular patterns of pathogens or damaged cells from outside. However, in recent years, it has also become clear that TLR4 can affect the immune system and the function of stem cells, especially mesenchymal stem cells. Therefore, understanding how TLR4 signaling works at the cellular and molecular level and using this knowledge in regenerative medicine could be potentially useful, especially in the treatment of adipose- derived mesenchymal stem cells (ADMSCs). How these cells can use TLR4 signaling when used to increase their regenerative potential and repair tissues is an area of research.

AIMS

This study aims to elucidate the multifaceted role of TLR4-mediated signaling in ADMSCs.

METHOD

Employing a comprehensive set of assays, including MTT for cell viability, flow cytometry for surface marker expression, and gene expression analysis, we demonstrate that TLR4 activation significantly modulates key aspects of ADMSC biology. Specifically, TLR4 signaling was found to regulate ADMSCs proliferation, surface marker expression, and regenerative capacity in a dose- and time-dependent manner. Furthermore, TLR4 activation conferred cytoprotective effects against Doxorubicin (DOX)-induced cellular apoptosis.

RESULT

These findings suggest that TLR4 signaling could be used to enhance the regenerative abilities of ADMSCs and enable ADMSC-based therapies to be used more effectively for tissue engineering and therapeutic purposes.

CONCLUSION

However, it is important to note that research in this area needs more details and clinical studies.

Evaluation of Stemness Maintenance Properties of the Recombinant Human Laminin α2 LG1-3 Domains in Human Mesenchymal Stem Cells

BACKGROUND

Laminin, a member of the Extracellular Matrix (ECM), is a glycoprotein that is used as a factor that affects cell adhesion, proliferation, survival, and differentiation. Of these, five globular domains (LG domains) of the alpha chain play an important role in influencing the cell by binding to the integrin.

OBJECTIVE

This study aimed to evaluate the ability of globular domains 1-3 of laminin alpha2 (rhLAMA2LG1-3) in maintaining the pluripotency of human Mesenchymal Stem Cells (hMSCs), which are widely used in regenerative medicine.

METHODS

hMSCs were grown in the medium supplemented with rhLAMA2LG1-3, then the effect of the protein on hMSCs were confirmed through cell adhesion assay, proliferation assay and RTPCR.

RESULTS

rhLAMA2LG1-3 expressed in Escherichia coli has a molecular weight of 70 kDa, at 1 µg/ml concentration of rhLAMA2LG1-3, the attachment and proliferation of hMSCs were approximately 3.18-fold and 1.67-fold, respectively, more efficient than those of untreated controls. In addition, the undifferentiated state and degree of stemness of hMSCs were measured, on the basis of CD90 and CD105 levels. In the rhLAMA2LG1-3-treated hMSCs, the expression levels of CD90 and CD105 increased by 2.83-fold and 1.62-fold, respectively, compared to those in untreated controls.

CONCLUSIONS

rhLAMA2LG1-3 can be potentially used in stem cell therapy to improve the viability and maintain the undifferentiated state of hMSCs.

ALDH as a Stem Cell Marker in Solid Tumors

Aldehyde dehydrogenase (ALDH) is an enzyme that participates in important cellular mechanisms as aldehyde detoxification and retinoic acid synthesis; moreover, ALDH activity is involved in drug resistance, a characteristic of cancer stem cells (CSCs). Even though ALDH is found in stem cells, CSCs and progenitor cells, this enzyme has been successfully used to identify and isolate cell populations with CSC properties from several tumor origins. ALDH is allegedly involved in cell differentiation through its product, retinoic acid. However, direct or indirect ALDH inhibition, using specific inhibitors or retinoic acid, has shown a reduction in ALDH activity, along with the loss of stem cell traits, reduction of cell proliferation, invasion, and drug sensitization. For these reasons, ALDH and retinoic acid are promising therapeutic targets. This review summarizes the current evidence for ALDH as a CSCs marker in solid tumors, as well as current knowledge about the functional roles of ALDH in CSCs. We discuss the controversy of ALDH activity to maintain CSC stemness, or conversely, to promote cell differentiation. Finally, we review the advances in using ALDH inhibitors as anti-cancer drugs.