4-Chlorobenzoyl berbamine, a novel berbamine derivative, induces apoptosis in multiple myeloma cells through the IL-6 signal transduction pathway and increases FOXO3a-Bim expression

Pharmacological profiling of a berbamine derivative for lymphoma treatment

ABSTRACT

Ca2+/calmodulin-dependent protein kinase II γ (CAMKIIγ) has been identified as a potential target for treating cancer. Based on our previous study of berbamine (BBM) as a CAMKIIγ inhibitor, we have synthesized a new BBM derivative termed PA4. Compared with BBM, PA4 showed improved potency and specificity and was more cytotoxic against lymphoma and leukemia than against other types of cancer. In addition to indirectly targeting c-Myc protein stability, we demonstrated that its cytotoxic effects were also mediated via increased reactive oxygen species production in lymphoma cells. PA4 significantly impeded tumor growth in vivo in a xenograft T-cell lymphoma mouse model. Pharmacokinetics studies demonstrated quick absorption into plasma after oral administration, with a maximum concentration of 1680 ± 479 ng/mL at 5.33 ± 2.31 hours. The calculated oral absolute bioavailability was 34.1%. Toxicity assessment of PA4 showed that the therapeutic window used in our experiments was safe for future development. Given its efficacy, safety, and favorable pharmacokinetic profile, PA4 is a potential lead candidate for treating lymphoma.

MG132 inhibits proliferation and induces apoptosis of acute lymphoblastic leukemia via Akt/FOXO3a/Bim pathway

BACKGROUND

Acute lymphoblastic leukemia (ALL) is one of the most common pediatric cancers, characterized by the malignant proliferation of leukemic cells. Despite advancements in treatment, the prognosis for refractory and relapsed ALL remains poor, underscoring the need for novel therapeutic targets and approaches.

METHODS

To investigate the anti-leukemic properties of MG132, MTS assays were employed to assess cell viability, and flow cytometry was used to evaluate apoptosis. Mechanistic studies, including qRT-PCR, Western blotting, and lentivirus-mediated FOXO3a knockdown, were conducted to explore MG132's effects on the Akt/FOXO3a/Bim signaling pathway. A xenograft mouse model was utilized to validate the in vivo efficacy of MG132 in suppressing tumor growth.

RESULTS

MG132 inhibited cell proliferation and induced apoptosis in both ALL cell lines and primary cells in a concentration-dependent manner. Mechanistic studies revealed that MG132 promoted FOXO3a nuclear localization by suppressing Akt phosphorylation and preventing FOXO3a degradation, leading to increased Bim expression. Furthermore, FOXO3a knockdown significantly reduced MG132's anti-proliferative effects. In vivo, MG132 markedly inhibited tumor growth in the xenograft model.

CONCLUSION

These findings suggest that MG132 exerts potent anti-leukemic effects through modulation of the Akt/FOXO3a/Bim axis, offering a promising therapeutic avenue for treating ALL.

Regulation of Cell-Signaling Pathways by Berbamine in Different Cancers

Natural product research is a cornerstone of the architectural framework of clinical medicine. Berbamine is a natural, potent, pharmacologically active biomolecule isolated from Berberis amurensis. Berbamine has been shown to modulate different oncogenic cell-signaling pathways in different cancers. In this review, we comprehensively analyze how berbamine modulates deregulated pathways (JAK/STAT, CAMKII/c-Myc) in various cancers. We systematically analyze how berbamine induces activation of the TGF/SMAD pathway for the effective inhibition of cancer progression. We also summarize different nanotechnological strategies currently being used for proficient delivery of berbamine to the target sites. Berbamine has also been reported to demonstrate potent anti-cancer and anti-metastatic effects in tumor-bearing mice. The regulation of non-coding RNAs by berbamine is insufficiently studied, and future studies must converge on the identification of target non-coding RNAs. A better understanding of the regulatory role of berbamine in the modulation of non-coding RNAs and cell-signaling pathways will be advantageous in the effective translation of laboratory findings to clinically effective therapeutics.

Synthesis and antitumor activity in vitro of novel berbamine derivatives

A series of new berbamine derivatives were synthesized, and their cytotoxic activity was evaluated against Human T-cell lymphoma cell line H9 and multiple myeloma cell line RPMI8226 in vitro. Compared with berbamine, the cytotoxicity of the modified derivatives was enhanced, especially simultaneously substituted at OH and 5-position. Compounds 2a and 4b exhibited high antitumor activity. The IC₅₀ value of compound 2a was 0.30 μM for RPMI8226 cells, and the IC₅₀ value of compound 4b was 0.36 μM for H9 cells, whereas berbamine IC₅₀ values were 4.0 μM for H9 cells and 6.19 μM for RPMI8226 cells, respectively.[Formula: see text].

CAMKIIγ is a targetable driver of multiple myeloma through CaMKIIγ/ Stat3 axis

Aberrant activation of CAMKIIγ has been linked to leukemia and T-cell lymphoma, but not multiple myeloma (MM). The purpose of this study was to explore the role of CaMKIIγ in the pathogenesis and therapy of MM. In this study, we found that CaMKIIγ was aberrantly activated in human MM and its expression level was positively correlated with malignant progression and poor prognosis. Ectopic expression of CaMKIIγ promoted cell growth, colony formation, cell cycle progress and inhibited apoptosis of MM cell lines, whereas, knockdown of CAMKIIγ expression suppressed MM cell growth in vitro and in vivo. Mechanically, we observed that CaMKIIγ overexpression upregulated p-ERK and p-Stat3 levels and suppression of CaMKIIγ had opposite effects. CaMKIIγ is frequently dysregulated in MM and plays a critical role in maintaining MM cell growth through upregulating STAT3 signaling pathway. Furthermore, our preclinical studies suggest that CaMKIIγ is a potential therapeutic target in MM, and could be intervened pharmacologically by small-molecule berbamine analogues.

A predicted risk score based on the expression of 16 autophagy-related genes for multiple myeloma survival

Autophagy has an important role in the pathogenesis of plasma cell development and multiple myeloma (MM); however, the prognostic role of autophagy-related genes (ARGs) in MM remains undefined. In the present study, the expression profiles of 234 ARGs were obtained from a Gene Expression Omnibus dataset (accession GSE24080), which contains 559 samples of patients with MM analyzed with 54,675 probes. Univariate Cox regression analysis identified 55 ARGs that were significantly associated with event-free survival of MM. Furthermore, a risk score with 16 survival-associated ARGs was developed using multivariate Cox regression analysis, including ATIC, BNIP3L, CALCOCO2, DNAJB1, DNAJB9, EIF4EBP1, EVA1A, FKBP1B, FOXO1, FOXO3, GABARAP, HIF1A, NCKAP1, PRKAR1A and SUPT20H, was constructed. Using this prognostic signature, patients with MM could be separated into high- and low-risk groups with distinct clinical outcomes. The area under the curve values for the receiver operating characteristic curves were 0.740, 0.741 and 0.712 for 3, 5 and 10 years prognosis predictions, respectively. Notably, the prognostic role of this risk score could be validated with another four independent cohorts (accessions: GSE57317, GSE4581, GSE4452 and GSE4204). In conclusion, ARGs may serve vital roles in the progression of MM, and the ARGs-based prognostic model may provide novel ideas for clinical applications in MM.

Effect of interleukin-6 on myocardial regeneration in mice after cardiac injury

Our aim was to investigate the role of interleukin-6 (IL-6) in myocardial regeneration from mice after cardiac injury. The newborn mice were divided into the following 4 groups (16 in each group): sham group, model group, IL-6-/- group (IL-6 knockout) and IL-6 group (IL-6 overexpression). Electrocardiography was performed on all mice and found higher LVEDD, LVESD and IVST and lower LVEF and LVFS in the IL-6 group compared with the sham group. Using HE staining, severe myocardial injury combined with infarction and fibrosis were observed in the IL-6-/- group, while the damaged myocardial tissue was repaired to some extent in the IL-6 group. The expression of IL-6 in the IL-6 group were significantly up-regulated. BrdU immunofluorescence found that the IL-6-/- group had the least number of BrdU positive cells, while the IL-6 group had more BrdU positive cells than the model group and the IL-6-/- group. Expressions of IL-6, cyclinD1 and Bcl-2 in the IL-6 group were up-regulated compared with other groups. In conclusion, IL-6 overexpression could enhance cardiomyocyte proliferation and relevant protein expression in mice myocardium, thus promoting cardiac regeneration.

Unravelling the role of fatty acid metabolism in cancer through the FOXO3-FOXM1 axis

Obesity and cachexia represent divergent states of nutritional and metabolic imbalance but both are intimately linked to cancer. There is an extensive overlap in their signalling pathways and molecular components involved such as fatty acids (FAs), which likely play a crucial role in cancer. Forkhead box (FOX) proteins are responsible of a wide range of transcriptional programmes during normal development, and the FOXO3-FOXM1 axis is associated with cancer initiation, progression and drug resistance. Free fatty acids (FFAs), FA synthesis and β-oxidation are associated with cancer development and progression. Meanwhile, insulin and some adipokines, that are up-regulated by FAs, are also involved in cancer development and poor prognosis. In this review, we discuss the role of FA metabolism in cancer and how FA metabolism integrates with the FOXO3-FOXM1 axis. These new insights may provide leads to better cancer diagnostics as well as strategies for tackling cancer development, progression and drug resistance.

Phenylbutyrate-a pan-HDAC inhibitor-suppresses proliferation of glioblastoma LN-229 cell line

Phenylbutyrate (PBA) is a histone deacetylase inhibitor known for inducing differentiation, cell cycle arrest, and apoptosis in various cancer cells. However, the effects of PBA seem to be very cell-type-specific and sometimes limited exclusively to a particular cell line. Here, we provided novel information concerning cellular effects of PBA in LN-229 and LN-18 glioblastoma cell lines which have not been previously evaluated in context of PBA exposure. We found that LN-18 cells were PBA-insensitive even at high concentrations of PBA. In contrary, in LN-229 cells, 5 and 15 mmol/L PBA inhibited cell growth and proliferation mainly by causing prominent changes in cell morphology and promoting S- and G2/M-dependent cell cycle arrest. Moreover, we observed nearly a 3-fold increase in apoptosis of LN-229 cells treated with 15 mmol/L PBA, in comparison to control. Furthermore, PBA was found to up-regulate the expression of p21 whereas p53 expression level remained unchanged. We also showed that PBA down-regulated the expression of the anti-apoptotic genes Bcl-2/Bcl-X_L, however without affecting the expression of pro-apoptotic Bax and Bim. Taken together, our results suggest that PBA might potentially be considered as an agent slowing-down the progress of glioblastoma; however, further analyses are still needed to comprehensively resolve the nature of its activity in this type of cancer.