Combined treatment with ruxolitinib and MK-2206 inhibits the JAK2/STAT5 and PI3K/AKT pathways via apoptosis in MDA-MB-231 breast cancer cell line

Combined treatment with ruxolitinib and MK-2206 inhibits ERα activity by inhibiting MAPK signaling in BT474 breast cancer cells

Triple-positive breast cancer (TPBC) is a type of breast cancer that overexpresses estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2). Dysregulation of ER signaling has been implicated in the pathogenesis of breast cancer. ERα activation triggers the production of second messengers, including cAMP, leading to the activation of signals such as PI3K/AKT or Ras/MAPK. Ruxolitinib is a specific inhibitor of JAK1/JAK2. MK-2206 is an allosteric inhibitor of the Akt. The limitations of the use of ruxolitinib and MK-2206 as single agents necessitate the development of combination therapies with other drugs. This study is the first to investigate the effects of combining ruxolitinib with MK-2206 on MAPK and PI3K/AKT signaling in BT474 breast cancer cells. In addition, this work aimed to increase the anticancer effects of cotreatment with MK-2206 and ruxolitinib. Ruxolitinib, MK-2206, and their combination reduced cell viability in a dose- and time-dependent manner, as determined by MTT assays after 48 h of treatment. Colony formation and wound healing assays demonstrated that MK-2206 exhibited a synergistic anti-proliferative effect. The effects of ruxolitinib, MK-2206, and their combination on PI3K/AKT and MAPK signaling were assessed via western blotting. Ruxolitinib and MK-2206 combined treatment inhibit cell death in BT474 cells by downregulating ERα, Src-1, ERK1/2, SAPK/JNK, and c-Jun. Our results revealed the relationships among the ERα, PI3K/AKT, and MAPK signaling pathways in ER+ breast cancer cells. Understanding the interactions among ERα, PI3K-AKT-mTOR, and MAPK could lead to novel combination therapies.

Interleukin-5: an indicator of mild cognitive impairment in patients with type 2 diabetes mellitus - a comprehensive investigation ranging from bioinformatics analysis to clinical research

PURPOSE

Neuroinflammation constitutes an underlying mechanism for cognitive impairment. Here, we endeavor to scrutinize the potential contribution of interleukin-5 (IL-5) towards mild cognitive impairment (MCI), and to assess its diagnostic value for MCI in patients with type 2 diabetes mellitus (T2DM).

METHODS

RNA-seq was used to explore the potential neuroinflammation factors in the hippocampus of diabetic mice with cognitive decline. Additionally, the promising risk factor was verified in animals. Finally, the association between IL-5 levels and cognitive function and its diagnostic value for MCI were assessed.

RESULTS

In animals, up-regulated IL-5 mRNA and protein levels were detected by RNA-seq and (or) verified experiments in the hippocampus of diabetic db/db mice with cognitive decline, compared to those of db/m mice without diabetes. In human, compared to diabetic patients without MCI, those with MCI demonstrate elevated levels of IL-5. It is natively associated with Montreal Cognitive Assessment (MoCA) scores, reflecting global cognitive function, and positively correlated with Trail Making Test A (TMTA) scores, reflecting information processing speed. Furthermore, an elevated level of IL-5 is identified as a risk factor for MCI, and a factor that influences TMTA scores. Finally, it is recommended that the cut-off value for IL-5 in the diagnosis of MCI is 22.98 pg/mL, with a sensitivity of 68.6% and specificity of 72.9%.

CONCLUSIONS

IL-5 is considered a risk factor for MCI in T2DM patients and is associated with their performance in information processing speed. Moreover, an elevated level of IL-5 is a plausible biomarker for MCI in T2DM patients.

Combination of microparticles vaccine with MSI-1436 exerts a strong immune response for hepatocellular carcinoma

Although tumor cell-derived microparticles (MPs) vaccines have reportedly induced antitumor immune reactions for various cancers, the mechanism by which MPs derived from Hepa1-6 cells are taken up by dendritic cells (DCs) and provide the MPs antigens message to CD8+ T cells to exert their anti-hepatocellular carcinoma (HCC) effects remain unclear. Furthermore, the role of MPs in combination with the small-molecule drug MSI-1436, an inhibitor of protein tyrosine phosphatase 1B (PTP1B), in HCC has not yet been reported. In this study, protein mass spectrometry combined with cytology revealed that MPs are mainly taken up by DCs via the clathrin-mediated endocytosis and phagocytosis pathway and localized mainly in lysosomes. High concentration of tumor necrosis factor-α and interferon-γ was detected in CD8+ T cells stimulated with MPs-loaded DCs. Moreover, MPs combined with MSI-1436 further suppressed the proliferation of HCC cells in C57BL/6 tumor-bearing mice, which was closely correlated with CD4+/CD8+ T cells counts in peripheral blood, spleen, and the tumor microenvironment. Mechanistically, the combination of MPs and MSI-1436 exerts a more powerful anti-HCC effect, which may be related to the further inhibition of the expression of PTP1B. Overall, MPs combined with MSI-1436 exerted stronger antitumor effects than MPs or MSI-1436 alone. Therefore, the combination of MPs and MSI-1436 may be a promising means of treating HCC.

Ruxolitinib-loaded poly-ɛ-caprolactone (PCL) nanoparticles inhibit JAK2/STAT5 signaling in BT474 breast cancer cells by downregulating Bcl-2 and Mcl-1

BACKGROUND

JAK/STAT signaling plays an important role in regulating cell proliferation. Reducing proliferation and inducing cell death with gene-specific inhibitors such as ruxolitinib, Receptor tyrosine kinases (RTK) inhibitor targeting JAK1/2, are therapeutic approaches. The use of nanoparticles can reduce the toxicity and side effects of drugs, as they act directly on cancer cells and can selectively increase drug accumulation in tumor cells. Poly-ɛ-caprolactone (PCL) is a polymer that is frequently used in drug development. In this study, Rux-PCL-NPs were synthesized to increase the effectiveness of ruxolitinib. In addition, this study aimed to determine the effect of Rux-PCL-NPs on JAK/STAT signaling and apoptotic cell death.

METHODS AND RESULTS

Rux-PCL-NPs were synthesized by nanoprecipitation. The Rux-PCL-NPs had a spherical and mean particle size of 219 ± 88.66 nm and a zeta potential of 0.471 ± 0.453 mV. In vitro cytotoxicity and antiproliferative effects were determined by MTT and soft agar colony formation assays, respectively. The effects of ruxolitinib, PCL-NPs, and Rux-PCL-NPs on apoptosis and the JAK/STAT pathway in cells were examined by western blot analysis. PCL-NPs did not have a toxic effect on the cells. The IC50 value of Rux-PCL-NPs was decreased 50-fold compared to that of ruxolitinib. Rux-PCL-NPs promoted cell death by downregulating JAK2 and STAT5, thereby inhibiting the JAK/STAT pathway.

CONCLUSIONS

Our results revealed that Rux-PCL-NPs, which increased the efficacy of ruxolitinib, regulated apoptosis and the JAK2/STAT5 pathway.

Small Molecule Therapeutics in the Pipeline Targeting for Triple-Negative Breast Cancer: Origin, Challenges, Opportunities, and Mechanisms of Action

Triple-negative breast cancer (TNBC) cells are devoid of estrogen receptors (ERs), progesterone receptor (PRs), and human epidermal growth factor receptor 2 (HER2), and it (TNBC) counts for about 10-15% of all breast cancers. TNBC is highly invasive, having a faster growth rate and a higher risk of metastasis and recurrence. Still, chemotherapy is one of the widely used options for treating TNBC. This study reviewed the histological and molecular characterization of TNBC subtypes, signaling pathways that are aberrantly expressed, and small molecules targeting these pathways, as either single agents or in combination with other therapeutic agents like chemotherapeutics, immunotherapeutics, and antibody-drug conjugates; their mechanisms of action, challenges, and future perspectives were also reviewed. A detailed analytical review was carried out using the literature collected from the SciFinder, PubMed, ScienceDirect, Google Scholar, ACS, Springer, and Wiley databases. Several small molecule inhibitors were found to be therapeutics for treating TNBC. The mechanism of action and the different signaling pathways through which the small molecules exert their effects were studied, including clinical trials, if reported. These small molecule inhibitors include buparlisib, everolimus, vandetanib, apatinib, olaparib, salidroside, etc. Some of the signaling pathways involved in TNBC, including the VEGF, PARP, STAT3, MAPK, EGFR, P13K, and SRC pathways, were discussed. Due to the absence of these biomarkers, drug development for treating TNBC is challenging, with chemotherapy being the main therapeutic agent. However, chemotherapy is associated with chemoresistance and a high toxicity to healthy cells as side effects. Hence, there is a continuous demand for small-molecule inhibitors that specifically target several signaling pathways that are abnormally expressed in TNBC. We attempted to include all the recent developments in this field. Any omission is truly unintentional.

Ruxolitinib induces apoptosis and pyroptosis of anaplastic thyroid cancer via the transcriptional inhibition of DRP1-mediated mitochondrial fission

Anaplastic thyroid carcinoma (ATC) has a 100% disease-specific mortality rate. The JAK1/2-STAT3 pathway presents a promising target for treating hematologic and solid tumors. However, it is unknown whether the JAK1/2-STAT3 pathway is activated in ATC, and the anti-cancer effects and the mechanism of action of its inhibitor, ruxolitinib (Ruxo, a clinical JAK1/2 inhibitor), remain elusive. Our data indicated that the JAK1/2-STAT3 signaling pathway is significantly upregulated in ATC tumor tissues than in normal thyroid and papillary thyroid cancer tissues. Apoptosis and GSDME-pyroptosis were observed in ATC cells following the in vitro and in vivo administration of Ruxo. Mechanistically, Ruxo suppresses the phosphorylation of STAT3, resulting in the repression of DRP1 transactivation and causing mitochondrial fission deficiency. This deficiency is essential for activating caspase 9/3-dependent apoptosis and GSDME-mediated pyroptosis within ATC cells. In conclusion, our findings indicate DRP1 is directly regulated and transactivated by STAT3; this exhibits a novel and crucial aspect of JAK1/2-STAT3 on the regulation of mitochondrial dynamics. In ATC, the transcriptional inhibition of DRP1 by Ruxo hampered mitochondrial division and triggered apoptosis and GSDME-pyroptosis through caspase 9/3-dependent mechanisms. These results provide compelling evidence for the potential therapeutic effectiveness of Ruxo in treating ATC.

The AKT inhibitor, MK-2206, attenuates ABCG2-mediated drug resistance in lung and colon cancer cells

Introduction: The overexpression of ATP-binding cassette (ABC) transporters, ABCB1 and ABCG2, are two of the major mediators of multidrug resistance (MDR) in cancers. Although multiple ABCB1 and ABCG2 inhibitors have been developed and some have undergone evaluation in clinical trials, none have been clinically approved. The compound, MK-2206, an inhibitor of the protein kinases AKT1/2/3, is undergoing evaluation in multiple clinical trials for the treatment of certain types of cancers, including those resistant to erlotinib. In this in vitro study, we conducted in vitro experiments to determine if MK-2206 attenuates multidrug resistance in cancer cells overexpressing the ABCB1 or ABCG2 transporter. Methodology: The efficacy of MK-2206 (0.03-1 μM), in combination with the ABCB1 transporter sub-strates doxorubicin and paclitaxel, and ABCG2 transporter substrates mitoxantrone, SN-38 and topotecan, were determined in the cancer cell lines, KB-C2 and SW620/Ad300, which overexpress the ABCB1 transporter or H460/MX20 and S1-M1-80, which overexpress the ABCG2 transporter, respectively. The expression level and the localization of ABCG2 transporter on the cancer cells membranes were determined using western blot and immunofluorescence assays, respectively, following the incubation of cells with MK-2206. Finally, the interaction between MK-2206 and human ABCG2 transporter was predicted using computer-aided molecular modeling. Results: MK-2206 significantly increased the efficacy of anticancer compounds that were substrates for the ABCG2 but not the ABCB1 transporter. MK-2206 alone (0.03-1 μM) did not significantly alter the viability of H460/MX20 and S1-M1-80 cancer cells, which overexpress the ABCG2 transporter, compared to cells incubated with vehicle. However, MK-2206 (0.3 and 1 μM) significantly increased the anticancer efficacy of mitoxantrone, SN-38 and topotecan, in H460/MX20 and S1-M1-80 cancer cells, as indicated by a significant decrease in their IC50 values, compared to cells incubated with vehicle. MK-2206 significantly increased the basal activity of the ABCG2 ATPase (EC50 = 0.46 μM) but did not significantly alter its expression level and sub-localization in the membrane. The molecular modeling results suggested that MK-2206 binds to the active pocket of the ABCG2 transporter, by a hydrogen bond, hydrophobic interactions and π-π stacking. Conclusion: These in vitro data indicated that MK-2206 surmounts resistance to mitoxantrone, SN-38 and topotecan in cancer cells overexpressing the ABCG2 transporter. If these results can be translated to humans, it is possible that MK-2206 could be used to surmount MDR in cancer cells overexpressing the ABCG2 transporter.