ZGDHu-1 and fludarabine have a synergistic effect on apoptosis of chronic lymphocytic leukemia cells

3,6-dichloro-1,2,4,5-Tetrazine Assayed at High Doses in the Metastatic Breast Cancer Cell Line MDA-MB-231 Reduces Cell Numbers and Induces Apoptosis

Background:

The lack of treatment options for patients with chemotherapy-resistant cancers is pushing the field toward the development of new therapies. 1,2,4,5-tetrazine derivatives are a class of heterocyclic compounds that exhibit a broad spectrum of antitumor activities.

Objective:

The purpose of this study was to assess the biological activity of four s-tetrazine derivatives by substitution of two chloride atom of 3,6-dichloro-1,2,4,5-tetrazine with long hydrophobic side chains.

Methods:

We analyzed the anti-proliferative effects of four s-tetrazine derivatives with MTT assay and their pro-apoptotic effect with AV/ IP flow cytometry analysis and Hoechst 33342 staining.

Results:

We demonstrated that 3,6-dichloro-1,2,4,5-tetrazine (compound (1)) has a cytotoxic effect and induces apoptosis.

Conclusion:

3,6-dichloro-1,2,4,5-tetrazine presents a new cytotoxic drug against metastatic breast cancer cell line MDA-MB-231 in vitro.

Targeting Mitochondrial Bioenergetics as a Therapeutic Strategy for Chronic Lymphocytic Leukemia

Altered cellular metabolism is considered a hallmark of cancer and is fast becoming an avenue for therapeutic intervention. Mitochondria have recently been viewed as an important cellular compartment that fuels the metabolic demands of cancer cells. Mitochondria are the major source of ATP and metabolites necessary to fulfill the bioenergetics and biosynthetic demands of cancer cells. Furthermore, mitochondria are central to cell death and the main source for generation of reactive oxygen species (ROS). Overall, the growing evidence now suggests that mitochondrial bioenergetics, biogenesis, ROS production, and adaptation to intrinsic oxidative stress are elevated in chronic lymphocytic leukemia (CLL). Hence, recent studies have shown that mitochondrial metabolism could be targeted for cancer therapy. This review focuses the recent advancements in targeting mitochondrial metabolism for the treatment of CLL.

ZGDHu-1 for cancer therapy

N,N'-di-(m-methylphenyl)-3,6-dimethyl-1,4-dihydro-1,2,4,5-tetrazine-1,4-dicarboamide (ZGDHu-1) is a novel tetrazine derivative that was initially designed and produced by Professor W.X. Hu, and which has been reported by our group to exhibit antitumor activity. Accumulating evidence suggests that the anticancer mechanisms of ZGDHu-1 may be involved indifferent biological activities, particularly in acute myeloid leukemia (AML) cells. At a high concentration, ZGDHu-1 has been demonstrated to inhibit the proliferation of the leukemia cells by arresting the cell cycle at the G₂/M phase, and by inducing cell apoptosis via inducing the accumulation of reactive oxygen species, the translocation of phosphatidylserine across the plasma membrane and the loss of mitochondrial membrane potential. Furthermore, at a low concentration, it was demonstrated to induce the differentiation and degrade the AML1-eight-twenty-one fusion protein in AML cells. Finally, results from a previous study indicate that ZGDHu-1 is a potential proteasome inhibitor. Overall, our preliminary research suggests that ZGDHu-1 may be a promising anticancer drug; however, further research is warranted to identify the exact drug target and potential clinical application in leukemia cells or solid tumors. In the present review, the application of ZGDHu-1 in cancer research, in addition to the specific underlying targets of ZGDHu-1, are discussed.