Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

Search Results (44)

Search Parameters:
Keywords = BAD phosphorylation

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
21 pages, 9061 KiB  
Article
Brusatol Inhibits Esophageal Squamous Cell Carcinoma Tumorigenesis Through Bad-Mediated Mitochondrial Apoptosis Induction and Anti-Metastasis by Targeting Akt1
by Yao Ji, Xinxin Zhu, Yi Shi, Rui Fang, Yimeng Sun, Yurong Ruan, Liying Zhou, Yuanyuan Ge, Qichao Luo, Junyan Zhang and Junting Ma
Biomolecules 2025, 15(6), 812; https://doi.org/10.3390/biom15060812 - 4 Jun 2025
Viewed by 529
Abstract
Esophageal squamous cell carcinoma (ESCC) is a prevalent malignancy characterized by poor prognosis and a deficiency of effective therapies. Brusatol (Bru), a bioactive component derived from Brucea javanica, exhibits potent anti-tumor activity. However, the pro-apoptotic and anti-metastatic effects of Bru in ESCC [...] Read more.
Esophageal squamous cell carcinoma (ESCC) is a prevalent malignancy characterized by poor prognosis and a deficiency of effective therapies. Brusatol (Bru), a bioactive component derived from Brucea javanica, exhibits potent anti-tumor activity. However, the pro-apoptotic and anti-metastatic effects of Bru in ESCC remain unclear. ESCC cells were incubated with Bru. The apoptotic status and metastatic capacities of the cells was measured by the Annexin V-FITC/PI, and wound-healing and transwell assays. Potential targets of Bru in ESCC were identified. The mechanisms by which Bru exerts its effects in ESCC cells were explored. Additionally, the typical 4-NQO-induced ESCC mouse model was employed to examine the anti-tumor effect of Bru in vivo. In this study, Bru was found to trigger mitochondria-mediated cell apoptosis (approximately 5.9- and 3.3-fold increases in the level of apoptosis at high concentrations (80 nM) in the KYSE30 and KYSE450 cells) and inhibit metastasis (49% wound closure decreases at high concentrations (80 nM) in both cells, compared to that in the DMSO group) in ESCC cells. In vivo, Bru significantly suppressed ESCC tumorigenesis. Notably, Bru interacts with Akt1, leading to a reduction in the phosphorylation level of Akt1 at Ser473. Consequently, this not only induced dephosphorylation of Bad at the Ser136 residue to promote mitochondrial apoptosis but also inhibited metastasis in ESCC cells. Bru promoted Bad-mediated mitochondrial apoptosis and inhibited the ESCC cell metastasis by targeting Akt1. Our results suggest Bru is a novel Akt1 inhibitor for inhibiting the progression of ESCC. Full article
Show Figures

Figure 1

20 pages, 5182 KiB  
Article
Combinational Inhibition of MEK and AKT Synergistically Induces Melanoma Stem Cell Apoptosis and Blocks NRAS Tumor Growth
by Ryyan Alobaidi, Nusrat Islam, Toni Olkey, Yogameenakshi Haribabu, Mathew Shamo, Peter Sykora, Cynthia M. Simbulan-Rosenthal and Dean S. Rosenthal
Cells 2025, 14(4), 248; https://doi.org/10.3390/cells14040248 - 10 Feb 2025
Cited by 2 | Viewed by 1245
Abstract
Malignant melanoma is a lethal skin cancer containing melanoma-initiating cells (MICs), implicated in tumorigenesis, invasion, and drug resistance, and characterized by an elevated expression of stem cell markers, including CD133. siRNA knockdown of CD133 has been previously shown to enhance apoptosis induced by [...] Read more.
Malignant melanoma is a lethal skin cancer containing melanoma-initiating cells (MICs), implicated in tumorigenesis, invasion, and drug resistance, and characterized by an elevated expression of stem cell markers, including CD133. siRNA knockdown of CD133 has been previously shown to enhance apoptosis induced by the MEK inhibitor trametinib in melanoma cells. This study investigates the underlying mechanisms of CD133’s anti-apoptotic activity in patient-derived BAKP melanoma, harboring the difficult-to-treat NRASQ61K driver mutation, after CRISPR-Cas9 CD133 knockout or Doxycycline (Dox)-inducible re-expression of CD133. CD133 knockout in BAKP cells increased trametinib-induced apoptosis by reducing anti-apoptotic p-AKT and p-BAD and increasing pro-apoptotic BAX. Conversely, Dox-induced CD133 expression diminished apoptosis in trametinib-treated cells, coincident with elevated p-AKT, p-BAD, and decreased activation of BAX and caspase-3. However, trametinib in combination with pan-AKT inhibitor capivasertib reduced cell survival as measured by XTT viability assays and apoptosis and colony formation assays, independent of CD133 status. CD133 may therefore activate a survival pathway wherein (1) increased AKT phosphorylation and activation induces (2) BAD phosphorylation and inactivation, which (3) decreases BAX activation, and (4) reduces caspases-3 activity and caspase-mediated PARP cleavage, leading to apoptosis suppression and drug resistance in melanoma. In vivo mouse xenograft studies using Dox-inducible melanoma cells revealed increased rates of tumor growth after induction of CD133 expression in trametinib-treated +Dox mice, an effect which was synergistically suppressed by combination treatment. Targeting nodes of the AKT and MAPK survival pathways with trametinib and capivasertib highlights the potential for combination therapies for NRAS-mutant melanoma stem cells for the development of more effective treatments for patients with high-risk melanoma. Full article
(This article belongs to the Section Cellular Pathology)
Show Figures

Graphical abstract

26 pages, 8995 KiB  
Article
The Induction of G2/M Phase Cell Cycle Arrest and Apoptosis by the Chalcone Derivative 1C in Sensitive and Resistant Ovarian Cancer Cells Is Associated with ROS Generation
by Šimon Salanci, Mária Vilková, Lola Martinez, Ladislav Mirossay, Radka Michalková and Ján Mojžiš
Int. J. Mol. Sci. 2024, 25(14), 7541; https://doi.org/10.3390/ijms25147541 - 9 Jul 2024
Cited by 8 | Viewed by 3535
Abstract
Ovarian cancer ranks among the most severe forms of cancer affecting the female reproductive organs, posing a significant clinical challenge primarily due to the development of resistance to conventional therapies. This study investigated the effects of the chalcone derivative 1C on sensitive (A2780) [...] Read more.
Ovarian cancer ranks among the most severe forms of cancer affecting the female reproductive organs, posing a significant clinical challenge primarily due to the development of resistance to conventional therapies. This study investigated the effects of the chalcone derivative 1C on sensitive (A2780) and cisplatin-resistant (A2780cis) ovarian cancer cell lines. Our findings revealed that 1C suppressed cell viability, induced cell cycle arrest at the G2/M phase, and triggered apoptosis in both cell lines. These effects are closely associated with generating reactive oxygen species (ROS). Mechanistically, 1C induced DNA damage, modulated the activity of p21, PCNA, and phosphorylation of Rb and Bad proteins, as well as cleaved PARP. Moreover, it modulated Akt, Erk1/2, and NF-κB signaling pathways. Interestingly, we observed differential effects of 1C on Nrf2 levels between sensitive and resistant cells. While 1C increased Nrf2 levels in sensitive cells after 12 h and decreased them after 48 h, the opposite effect was observed in resistant cells. Notably, most of these effects were suppressed by the potent antioxidant N-acetylcysteine (NAC), underscoring the crucial role of ROS in 1C-induced antiproliferative activity. Moreover, we suggest that modulation of Nrf2 levels can, at least partially, contribute to the antiproliferative effect of chalcone 1C. Full article
(This article belongs to the Special Issue Programmed Cell Death and Oxidative Stress 2.0)
Show Figures

Figure 1

15 pages, 3418 KiB  
Article
Alginate Oligosaccharide Alleviates Lipopolysaccharide-Induced Apoptosis and Inflammatory Response of Rumen Epithelial Cells through NF-κB Signaling Pathway
by Xiaoyuan Qiu, Fuquan Yin, Chunmei Du, Jian Ma and Shangquan Gan
Animals 2024, 14(9), 1298; https://doi.org/10.3390/ani14091298 - 25 Apr 2024
Cited by 4 | Viewed by 1884
Abstract
AOS alleviates inflammatory responses; however, whether it exerts an effect on the rumen or regulates rumen inflammatory reaction remains unknown. In this study, firstly, the ovine ruminal epithelial cells (ORECs) were treated with 0, 200, 400, 600, and 800 µg/mL AOS, hoping to [...] Read more.
AOS alleviates inflammatory responses; however, whether it exerts an effect on the rumen or regulates rumen inflammatory reaction remains unknown. In this study, firstly, the ovine ruminal epithelial cells (ORECs) were treated with 0, 200, 400, 600, and 800 µg/mL AOS, hoping to explore whether AOS hurt cell health. The results showed that compared with the AOS-0 group, the AOS-400 group could significantly increase (p < 0.05) cell viability, reduce (p < 0.05) reactive oxygen species (ROS) and interleukin (IL)-6 content, and have no adverse effect on cells. Secondly, we used LPS to construct an in vitro inflammatory model of rumen epithelial cells and then explored the protective role of AOS on rumen epithelial cells. The study was divided into three groups: the control group (CON), LPS, and LPS + AOS. The results demonstrated that the LPS + AOS group significantly increased the cell viability and reduced the ROS level in comparison with the LPS group (p < 0.05). Pretreatment with AOS also repressed (p < 0.05) the secretion of IL-1β, IL-6, IL-8, and immunoglobulin (Ig)A from ORECs in the culture medium following LPS. In terms of tight junction (TJ) proteins, AOS treatment also significantly increased (p < 0.05) the zonula occludens 1 (ZO-1) and Occludin expression. The apoptosis rate, Caspase3, Caspase9, BAD, and BCL-2/BAX were decreased (p < 0.05) after AOS treatment, and the expression of BCL-2 was increased (p < 0.05). In addition, the expressions of Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor-κB (NF-κB) were inhibited (p < 0.05) with the addition of AOS. At the protein level, pretreatment of AOS decreased (p < 0.05) the expression of MyD88 and the phosphorylation level of inhibitor κB α (IκBα) after the LPS challenge. Taken together, our results indicated that AOS could alleviate the LPS-induced apoptosis and inflammatory response of rumen epithelial cells through the NF-κB signaling pathway, which may be a promising strategy for treating apoptosis and inflammation in sheep breeding. Full article
(This article belongs to the Section Animal Nutrition)
Show Figures

Figure 1

24 pages, 6483 KiB  
Article
Design, Synthesis, and Anti-Leukemic Evaluation of a Series of Dianilinopyrimidines by Regulating the Ras/Raf/MEK/ERK and STAT3/c-Myc Pathways
by Chaoyan Wang, Bo Wang, Yu Mou, Xiang Liu, Qiqing Chen, Weidong Pu, Qing Rao, Chunlin Wang, Jingrui Song, Yubing Huang, Longjia Yan, Lei Huang and Yanmei Li
Molecules 2024, 29(7), 1597; https://doi.org/10.3390/molecules29071597 - 3 Apr 2024
Cited by 2 | Viewed by 1966
Abstract
Although the long-term survival rate for leukemia has made significant progress over the years with the development of chemotherapeutics, patients still suffer from relapse, leading to an unsatisfactory outcome. To discover the new effective anti-leukemia compounds, we synthesized a series of dianilinopyrimidines and [...] Read more.
Although the long-term survival rate for leukemia has made significant progress over the years with the development of chemotherapeutics, patients still suffer from relapse, leading to an unsatisfactory outcome. To discover the new effective anti-leukemia compounds, we synthesized a series of dianilinopyrimidines and evaluated the anti-leukemia activities of those compounds by using leukemia cell lines (HEL, Jurkat, and K562). The results showed that the dianilinopyrimidine analog H-120 predominantly displayed the highest cytotoxic potential in HEL cells. It remarkably induced apoptosis of HEL cells by activating the apoptosis-related proteins (cleaved caspase-3, cleaved caspase-9 and cleaved poly ADP-ribose polymerase (PARP)), increasing apoptosis protein Bad expression, and decreasing the expression of anti-apoptotic proteins (Bcl-2 and Bcl-xL). Furthermore, it induced cell cycle arrest in G2/M; concomitantly, we observed the activation of p53 and a reduction in phosphorylated cell division cycle 25C (p-CDC25C) / Cyclin B1 levels in treated cells. Additionally, the mechanism study revealed that H-120 decreased these phosphorylated signal transducers and activators of transcription 3, rat sarcoma, phosphorylated cellular RAF proto-oncogene serine / threonine kinase, phosphorylated mitogen-activated protein kinase kinase, phosphorylated extracellular signal-regulated kinase, and cellular myelocytomatosis oncogene (p-STAT3, Ras, p-C-Raf, p-MEK, p-MRK, and c-Myc) protein levels in HEL cells. Using the cytoplasmic and nuclear proteins isolation assay, we found for the first time that H-120 can inhibit the activation of STAT3 and c-Myc and block STAT3 phosphorylation and dimerization. Moreover, H-120 treatment effectively inhibited the disease progression of erythroleukemia mice by promoting erythroid differentiation into the maturation of erythrocytes and activating the immune cells. Significantly, H-120 also improved liver function in erythroleukemia mice. Therefore, H-120 may be a potential chemotherapeutic drug for leukemia patients. Full article
Show Figures

Figure 1

22 pages, 6534 KiB  
Article
Pan-EGFR Inhibitor Dacomitinib Resensitizes Paclitaxel and Induces Apoptosis via Elevating Intracellular ROS Levels in Ovarian Cancer SKOV3-TR Cells
by Ye Jin Lim, Hee Su Kim, Seunghee Bae, Kyeong A So, Tae Jin Kim and Jae Ho Lee
Molecules 2024, 29(1), 274; https://doi.org/10.3390/molecules29010274 - 4 Jan 2024
Cited by 4 | Viewed by 3107
Abstract
Paclitaxel is still used as a standard first-line treatment for ovarian cancer. Although paclitaxel is effective for many types of cancer, the emergence of chemoresistant cells represents a major challenge in chemotherapy. Our study aimed to analyze the cellular mechanism of dacomitinib, a [...] Read more.
Paclitaxel is still used as a standard first-line treatment for ovarian cancer. Although paclitaxel is effective for many types of cancer, the emergence of chemoresistant cells represents a major challenge in chemotherapy. Our study aimed to analyze the cellular mechanism of dacomitinib, a pan-epidermal growth factor receptor (EGFR) inhibitor, which resensitized paclitaxel and induced cell cytotoxicity in paclitaxel-resistant ovarian cancer SKOV3-TR cells. We investigated the significant reduction in cell viability cotreated with dacomitinib and paclitaxel by WST-1 assay and flow cytometry analysis. Dacomitinib inhibited EGFR family proteins, including EGFR and HER2, as well as its downstream signaling proteins, including AKT, STAT3, ERK, and p38. In addition, dacomitinib inhibited the phosphorylation of Bad, and combination treatment with paclitaxel effectively suppressed the expression of Mcl-1. A 2′-7′-dichlorodihydrofluorescein diacetate (DCFH-DA) assay revealed a substantial elevation in cellular reactive oxygen species (ROS) levels in SKOV3-TR cells cotreated with dacomitinib and paclitaxel, which subsequently mediated cell cytotoxicity. Additionally, we confirmed that dacomitinib inhibits chemoresistance in paclitaxel-resistant ovarian cancer HeyA8-MDR cells. Collectively, our research indicated that dacomitinib effectively resensitized paclitaxel in SKOV3-TR cells by inhibiting EGFR signaling and elevating intracellular ROS levels. Full article
Show Figures

Graphical abstract

16 pages, 3505 KiB  
Article
Sodium Butyrate Enhances the Cytotoxic Effect of Etoposide in HDACi-Sensitive and HDACi-Resistant Transformed Cells
by Olga O. Gnedina, Alisa V. Morshneva and Maria V. Igotti
Int. J. Mol. Sci. 2023, 24(21), 15913; https://doi.org/10.3390/ijms242115913 - 2 Nov 2023
Viewed by 1594
Abstract
To overcome the problem of antitumor agent toxicity for normal cells, a combined therapy using drugs with synergistic effects seems to be more effective. We investigated the molecular mechanisms of the sensitization of tumor cells resistant and sensitive to histone deacetylase inhibitors (HDACis) [...] Read more.
To overcome the problem of antitumor agent toxicity for normal cells, a combined therapy using drugs with synergistic effects seems to be more effective. We investigated the molecular mechanisms of the sensitization of tumor cells resistant and sensitive to histone deacetylase inhibitors (HDACis) upon etoposide treatment together with the HDACi sodium butyrate (NaBut). We showed that NaBut enhances the cytotoxic effect of etoposide in both HDACi-sensitive and HDACi-resistant cells due to the accumulation of the Bax protein and the dissociation of Ku70–Bax inhibitory complexes. In HDACi-resistant cells, NaBut causes the cytoplasmic accumulation of Bax dissociated from mitochondria in complexes with Ku70 proteins. The increased phosphorylation of the pro-apoptotic Bad protein due to the NaBut-induced activation of Erk and Akt kinases is one of the possible reasons for the accumulation of Bax in the cytoplasm. Despite the inactivation of Bax in HDACi-resistant cells, its accumulation in the cytoplasm upon NaBut treatment makes it possible to enhance the apoptotic response against agents activating the intrinsic pathway of apoptosis. Thus, HDACis involved in combined therapy mediate the sensitization of tumor cells to genotoxic drugs, regardless of the cells’ resistance to HDACis. Full article
(This article belongs to the Special Issue Molecular Mechanism of Anti-cancer Drugs)
Show Figures

Figure 1

19 pages, 4492 KiB  
Article
Utilizing a Combination of Network Pharmacology and Experimental Validation to Unravel the Mechanism by Which Kuanxiongzhuyu Decoction Ameliorates Myocardial Infarction Damage
by Yihao Wu, Miaofu Li, Liuying Chen, Linhao Xu, Yizhou Xu and Yigang Zhong
Medicina 2023, 59(10), 1740; https://doi.org/10.3390/medicina59101740 - 28 Sep 2023
Viewed by 2066
Abstract
Background and Objectives: With the growing incidence and disability associated with myocardial infarction (MI), there is an increasing focus on cardiac rehabilitation post-MI. Kuanxiongzhuyu decoction (KXZY), a traditional Chinese herbal formula, has been used in the rehabilitation of patients after MI. However, [...] Read more.
Background and Objectives: With the growing incidence and disability associated with myocardial infarction (MI), there is an increasing focus on cardiac rehabilitation post-MI. Kuanxiongzhuyu decoction (KXZY), a traditional Chinese herbal formula, has been used in the rehabilitation of patients after MI. However, the chemical composition, protective effects, and underlying mechanism of KXZY remain unclear. Materials and Methods: In this study, the compounds in KXZY were identified using a high-performance liquid chromatography-mass spectrometry (HPLC-MS) analytical method. Based on the compounds identified in the KXZY, we predictively selected the potential targets of MI and then constructed a protein–protein interaction (PPI) network to identify the key targets. Furthermore, the DAVID database was used for the GO and KEGG analyses, and molecular docking was used to verify the key targets. Finally, the cardioprotective effects and mechanism of KXZY were investigated in post-MI mice. Results: A total of 193 chemical compounds of KXZY were identified by HPLC-MS. In total, 228 potential targets were obtained by the prediction analysis. The functional enrichment studies and PPI network showed that the targets were largely associated with AKT-pathway-related apoptosis. The molecular docking verified that isoguanosine and adenosine exhibited excellent binding to the AKT. In vivo, KXZY significantly alleviated cardiac dysfunction and suppressed AKT phosphorylation. Furthermore, KXZY significantly increased the expression of the antiapoptotic proteins Bcl-2 and Bcl-xl and decreased the expression of the proapoptotic protein BAD. Conclusions: In conclusion, the network pharmacological and experimental evidence suggests that KXZY manifests anti-cardiac dysfunction behavior by alleviating cardiomyocyte apoptosis via the AKT pathway in MI and, thus, holds promising therapeutic potential. Full article
(This article belongs to the Section Pharmacology)
Show Figures

Figure 1

18 pages, 2560 KiB  
Article
Cerebroprotective Effect of 17β-Estradiol Replacement Therapy in Ovariectomy-Induced Post-Menopausal Rats Subjected to Ischemic Stroke: Role of MAPK/ERK1/2 Pathway and PI3K-Independent Akt Activation
by María C. Burguete, Teresa Jover-Mengual, María Castelló-Ruiz, Mikahela A. López-Morales, José M. Centeno, Alicia Aliena-Valero, Enrique Alborch, Germán Torregrosa and Juan B. Salom
Int. J. Mol. Sci. 2023, 24(18), 14303; https://doi.org/10.3390/ijms241814303 - 19 Sep 2023
Cited by 4 | Viewed by 1875
Abstract
Despite the overwhelming advances in the understanding of the pathogenesis of stroke, a devastating disease affecting millions of people worldwide, currently there are only a limited number of effective treatments available. Preclinical and clinical studies show that stroke is a sexually dimorphic disorder, [...] Read more.
Despite the overwhelming advances in the understanding of the pathogenesis of stroke, a devastating disease affecting millions of people worldwide, currently there are only a limited number of effective treatments available. Preclinical and clinical studies show that stroke is a sexually dimorphic disorder, affecting males and females differently. Strong experimental evidence indicates that estrogen may play a role in this difference and that exogenous 17β-estradiol (E2) is neuroprotective against stroke in both male and female rodents. However, the molecular mechanisms by which E2 intervenes in ischemia-induced cell death, revealing these sex differences, remain unclear. The present study was aimed to determine, in female rats, the molecular mechanisms of two well-known pro-survival signaling pathways, MAPK/ERK1/2 and PI3K/Akt, that mediate E2 neuroprotection in response to acute ischemic stroke. E2 pretreatment reduced brain damage and attenuated apoptotic cell death in ovariectomized female rats after an ischemic insult. Moreover, E2 decreased phosphorylation of ERK1/2 and prevented ischemia/reperfusion-induced dephosphorylation of both Akt and the pro-apoptotic protein, BAD. However, MAPK/ERK1/2 inhibitor PD98059, but not the PI3K inhibitor LY294002, attenuated E2 neuroprotection. Thus, these results suggested that E2 pretreatment in ovariectomized female rats modulates MAPK/ERK1/2 and activates Akt independently of PI3K to promote cerebroprotection in ischemic stroke. A better understanding of the mechanisms and the influence of E2 in the female sex paves the way for the design of future successful hormone replacement therapies. Full article
(This article belongs to the Special Issue Current Insights on Neuroprotection)
Show Figures

Figure 1

22 pages, 7613 KiB  
Article
Inhibition of PERK Kinase, an Orchestrator of the Unfolded Protein Response (UPR), Significantly Reduces Apoptosis and Inflammation of Lung Epithelial Cells Triggered by SARS-CoV-2 ORF3a Protein
by Panagiotis Keramidas, Eleni Papachristou, Rigini M. Papi, Aglaia Mantsou and Theodora Choli-Papadopoulou
Biomedicines 2023, 11(6), 1585; https://doi.org/10.3390/biomedicines11061585 - 30 May 2023
Cited by 7 | Viewed by 3636
Abstract
SARS-CoV-2 ORF3a accessory protein was found to be involved in virus release, immunomodulation and exhibited a pro-apoptotic character. In order to unravel a potential ORF3a-induced apoptotic and inflammatory death mechanism, lung epithelial cells (A549) were transfected with in vitro synthesized ORF3a mRNA. The [...] Read more.
SARS-CoV-2 ORF3a accessory protein was found to be involved in virus release, immunomodulation and exhibited a pro-apoptotic character. In order to unravel a potential ORF3a-induced apoptotic and inflammatory death mechanism, lung epithelial cells (A549) were transfected with in vitro synthesized ORF3a mRNA. The protein’s dynamic involvement as “stress factor” for the endoplasmic reticulum, causing the activation of PERK kinase and other UPR-involved proteins and therefore the upregulation of their signaling pathway executioners (ATF6, XBP-1s, PERK, phospho eIF2a, ATF4, CHOP, GADD34), has been clearly demonstrated. Furthermore, the overexpression of BAX and BH3-only pro-apoptotic protein PUMA, the upregulation of Bcl-2 family genes (BAX, BAK, BID, BAD), the reduced expression of Bcl-2 in mRNA and protein levels, and lastly, the cleavage of PARP-1 and caspase family members (caspase-3,-8 and -9) indicate that ORF3a displays its apoptotic character through the mitochondrial pathway of apoptosis. Moreover, the upregulation of NFκB, phosphorylation of p65 and IκΒα and the elevated expression of pro-inflammatory cytokines (IL-1b, IL-6, IL-8 and IL-18) in transfected cells with ORF3a mRNA indicate that this protein causes the inflammatory response through NFκB activation and therefore triggers lung injury. An intriguing finding of our study is that upon treatment of the ORF3a-transfected cells with GSK2606414, a selective PERK inhibitor, both complications (apoptosis and inflammatory response) were neutralized, and cell survival was favored, whereas treatment of transfected cells with z-VAD (a pan-caspase inhibitor) despite inhibiting cell death, could not ameliorate the inflammatory response of transfected A549 cells. Given the above, we point out that PERK kinase is a “master tactician” and its activation constitutes the main stimulus for the emergence of ORF3a apoptotic and inflammatory nature and therefore could serve as potential target for developing novel therapeutic approaches against COVID-19. Full article
Show Figures

Figure 1

22 pages, 5747 KiB  
Article
Combination Therapies Targeting Apoptosis in Paediatric AML: Understanding the Molecular Mechanisms of AML Treatments Using Phosphoproteomics
by Ahlam A. Ali, Lauren V. Cairns, Kathryn M. Clarke, Jaine K. Blayney, Katrina M. Lappin and Ken I. Mills
Int. J. Mol. Sci. 2023, 24(6), 5717; https://doi.org/10.3390/ijms24065717 - 16 Mar 2023
Cited by 2 | Viewed by 2658
Abstract
Paediatric acute myeloid leukaemia (AML) continues to present treatment challenges, as no “standard approach” exists to treat those young patients reliably and safely. Combination therapies could become a viable treatment option for treating young patients with AML, allowing multiple pathways to be targeted. [...] Read more.
Paediatric acute myeloid leukaemia (AML) continues to present treatment challenges, as no “standard approach” exists to treat those young patients reliably and safely. Combination therapies could become a viable treatment option for treating young patients with AML, allowing multiple pathways to be targeted. Our in silico analysis of AML patients highlighted “cell death and survival” as an aberrant, potentially targetable pathway in paediatric AML patients. Therefore, we aimed to identify novel combination therapies to target apoptosis. Our apoptotic drug screening resulted in the identification of one potential “novel” drug pairing, comprising the Bcl-2 inhibitor ABT-737 combined with the CDK inhibitor Purvalanol-A, as well as one triple combination of ABT-737 + AKT inhibitor + SU9516, which showed significant synergism in a series of paediatric AML cell lines. Using a phosphoproteomic approach to understand the apoptotic mechanism involved, proteins related to apoptotic cell death and cell survival were represented, in agreement with further results showing differentially expressed apoptotic proteins and their phosphorylated forms among combination treatments compared to single-agent treated cells such upregulation of BAX and its phosphorylated form (Thr167), dephosphorylation of BAD (Ser 112), and downregulation of MCL-1 and its phosphorylated form (Ser159/Thr 163). Total levels of Bcl-2 were decreased but correlated with increased levels of phosphorylated Bcl-2, which was consistent with our phosphoproteomic analysis predictions. Bcl-2 phosphorylation was regulated by extracellular-signal-regulated kinase (ERK) but not PP2A phosphatase. Although the mechanism linking to Bcl-2 phosphorylation remains to be determined, our findings provide first-hand insights on potential novel combination treatments for AML. Full article
(This article belongs to the Special Issue Molecular Mechanisms and Therapies of Myeloid Leukaemia 2.0)
Show Figures

Figure 1

23 pages, 4050 KiB  
Article
Enhanced Apoptosis and Loss of Cell Viability in Melanoma Cells by Combined Inhibition of ERK and Mcl-1 Is Related to Loss of Mitochondrial Membrane Potential, Caspase Activation and Upregulation of Proapoptotic Bcl-2 Proteins
by Zhe Peng, Bernhard Gillissen, Antje Richter, Tobias Sinnberg, Max S. Schlaak and Jürgen Eberle
Int. J. Mol. Sci. 2023, 24(5), 4961; https://doi.org/10.3390/ijms24054961 - 4 Mar 2023
Cited by 12 | Viewed by 3325
Abstract
Targeting of MAP kinase pathways by BRAF inhibitors has evolved as a key therapy for BRAF-mutated melanoma. However, it cannot be applied for BRAF-WT melanoma, and also, in BRAF-mutated melanoma, tumor relapse often follows after an initial phase of tumor regression. Inhibition of [...] Read more.
Targeting of MAP kinase pathways by BRAF inhibitors has evolved as a key therapy for BRAF-mutated melanoma. However, it cannot be applied for BRAF-WT melanoma, and also, in BRAF-mutated melanoma, tumor relapse often follows after an initial phase of tumor regression. Inhibition of MAP kinase pathways downstream at ERK1/2, or inhibitors of antiapoptotic Bcl-2 proteins, such as Mcl-1, may serve as alternative strategies. As shown here, the BRAF inhibitor vemurafenib and the ERK inhibitor SCH772984 showed only limited efficacy in melanoma cell lines, when applied alone. However, in combination with the Mcl-1 inhibitor S63845, the effects of vemurafenib were strongly enhanced in BRAF-mutated cell lines, and the effects of SCH772984 were enhanced in both BRAF-mutated and BRAF-WT cells. This resulted in up to 90% loss of cell viability and cell proliferation, as well as in induction of apoptosis in up to 60% of cells. The combination of SCH772984/S63845 resulted in caspase activation, processing of poly (ADP-ribose) polymerase (PARP), phosphorylation of histone H2AX, loss of mitochondrial membrane potential, and cytochrome c release. Proving the critical role of caspases, a pan-caspase inhibitor suppressed apoptosis induction, as well as loss of cell viability. As concerning Bcl-2 family proteins, SCH772984 enhanced expression of the proapoptotic Bim and Puma, as well as decreased phosphorylation of Bad. The combination finally resulted in downregulation of antiapoptotic Bcl-2 and enhanced expression of the proapoptotic Noxa. In conclusion, combined inhibition of ERK and Mcl-1 revealed an impressive efficacy both in BRAF-mutated and WT melanoma cells, and may thus represent a new strategy for overcoming drug resistance. Full article
Show Figures

Figure 1

21 pages, 6877 KiB  
Article
Repurposing the Bis-Biguanide Alexidine in Combination with Tyrosine Kinase Inhibitors to Eliminate Leukemic Stem/Progenitor Cells in Chronic Myeloid Leukemia
by Fabien Muselli, Lucas Mourgues, Nathalie Rochet, Marielle Nebout, Agnès Guerci, Els Verhoeyen, Adrien Krug, Laurence Legros, Jean-François Peyron and Didier Mary
Cancers 2023, 15(3), 995; https://doi.org/10.3390/cancers15030995 - 3 Feb 2023
Cited by 3 | Viewed by 2806
Abstract
Background & aims: In CML, Leukemic Stem Cells (LSCs) that are insensitive to Tyrosine Kinase Inhibitors are responsible for leukemia maintenance and relapses upon TKI treatment arrest. We previously showed that downregulation of the BMI1 polycomb protein that is crucial for stem/progenitor cells [...] Read more.
Background & aims: In CML, Leukemic Stem Cells (LSCs) that are insensitive to Tyrosine Kinase Inhibitors are responsible for leukemia maintenance and relapses upon TKI treatment arrest. We previously showed that downregulation of the BMI1 polycomb protein that is crucial for stem/progenitor cells self-renewal induced a CCNG2/dependent proliferation arrest leading to elimination of Chronic Myeloid Leukemia (CML) cells. Unfortunately, as of today, pharmacological inhibition of BMI1 has not made its way to the clinic. Methods: We used the Connectivity Map bioinformatic database to identify pharmacological molecules that could mimick BMI1 silencing, to induce CML cell death. We selected the bis-biguanide Alexidin (ALX) that produced a transcriptomic profile positively correlating with the one obtained after BMI silencing in K562 CML cells. We then evaluated the efficiency of ALX in combination with TKI on CML cells. Results: Here we report that cell growth and clonogenic activity of K562 and LAMA-84 CML cell lines were strongly inhibited by ALX. ALX didn’t modify BCR::ABL1 phosphorylation and didn’t affect BMI1 expression but was able to increase CCNG2 expression leading to autophagic processes that preceed cell death. Besides, ALX could enhance the apoptotic response induced by any Tyrosine Kinase Inhibitors (TKI) of the three generations. We also noted a strong synergism between ALX and TKIs to increase expression of caspase-9 and caspase-3 and induce PARP cleavage, Bad expression and significantly decreased Bcl-xL family member expression. We also observed that the blockage of the mitochondrial respiratory chain by ALX can be associated with inhibition of glycolysis by 2-DG to achieve an enhanced inhibition of K562 proliferation and clonogenicity. ALX specifically affected the differentiation of BCR::ABL1-transduced healthy CD34+ cells but not of mock-infected healthy CD34+ control cells. Importantly, ALX strongly synergized with TKIs to inhibit clonogenicity of primary CML CD34+ cells from diagnosed patients. Long Term Culture of Initiating Cell (LTC-IC) and dilution of the fluorescent marker CFSE allowed us to observe that ALX and Imatinib (IM) partially reduced the number of LSCs by themselves but that the ALX/IM combination drastically reduced this cell compartment. Using an in vivo model of NSG mice intravenously injected with K562-Luciferase transduced CML cells, we showed that ALX combined with IM improved mice survival. Conclusions: Collectively, our results validate the use of ALX bis-biguanide to potentiate the action of conventional TKI treatment as a potential new therapeutic solution to eradicate CML LSCs Full article
Show Figures

Figure 1

15 pages, 4522 KiB  
Article
Recombinant Human Cytomegalovirus Expressing an Analog-Sensitive Kinase pUL97 as Novel Tool for Functional Analyses
by Nadine Krämer, Martin Schütz, Uxía Gestal Mato, Lina Herhaus, Manfred Marschall and Christine Zimmermann
Viruses 2022, 14(10), 2285; https://doi.org/10.3390/v14102285 - 17 Oct 2022
Cited by 1 | Viewed by 2549
Abstract
The human cytomegalovirus (HCMV) is a member of the beta-herpesvirus family and inflicts life-long latent infections in its hosts. HCMV has been shown to manipulate and dysregulate many cellular processes. One major interactor with the cellular host is the viral kinase pUL97. The [...] Read more.
The human cytomegalovirus (HCMV) is a member of the beta-herpesvirus family and inflicts life-long latent infections in its hosts. HCMV has been shown to manipulate and dysregulate many cellular processes. One major interactor with the cellular host is the viral kinase pUL97. The UL97 gene is essential for viral replication, and kinase-deficient mutants of pUL97 display a severe replication defect. Recently, another group established an analog-sensitive version of the pUL97 protein. This mutant kinase can be treated with a non-hydrolysable ATP analog, thereby inhibiting its kinase function. This process is reversible by removing the ATP analog by media change. We introduced this mutant version of the pUL97 protein into the laboratory strain Ad169 of HCMV, BADwt, creating a BAD-UL97-as1 viral mutant. This mutant virus replicated normally in infected cells in the absence of the ATP analog and maintained its ability to phosphorylate its cellular substrates. However, when treated with the ATP analog, BAD-UL97-as1 displayed a defect in the production of intra- and extracellular viral DNA and in the production of viral progeny. Furthermore, in the presence of 3MB-PP1, a well-established substrate of pUL97 was no longer hyperphosphorylated. This effect was detectable as early as 4 h post treatment, which allows for studies on pUL97 without the complication of low viral titers. Nevertheless, we observed off-target effects of 3MB-PP1 on several cellular processes, which should be considered with this approach. Full article
(This article belongs to the Section Human Virology and Viral Diseases)
Show Figures

Figure 1

17 pages, 1797 KiB  
Article
Potential Biochemical Pesticide—Synthesis of Neofuranocoumarin and Inhibition the Proliferation of Spodoptera frugiperda Cells through Activating the Mitochondrial Pathway
by Xuehua Shao, Zhuhong Zhang, Xuhong Qian, Lanying Wang, Yunfei Zhang and Yanping Luo
Toxins 2022, 14(10), 677; https://doi.org/10.3390/toxins14100677 - 29 Sep 2022
Cited by 6 | Viewed by 2410
Abstract
Furanocoumarins, the secondary metabolites of plants, are considered to be natural insecticides and fungicides because they prevent the invasion of plant pathogenic microorganisms and the predation of herbivorous insects. In this study, novel 2-arylfuranocoumarin derivatives were designed to synthesize by condensation, esterification, bromination, [...] Read more.
Furanocoumarins, the secondary metabolites of plants, are considered to be natural insecticides and fungicides because they prevent the invasion of plant pathogenic microorganisms and the predation of herbivorous insects. In this study, novel 2-arylfuranocoumarin derivatives were designed to synthesize by condensation, esterification, bromination, and Wittig reaction. The results showed an excellent photosensitive activity of 2-thiophenylfuranocoumarin (I34). Cell Counting Kit-8 detected that I34 could inhibit the proliferation of Spodoptera frugiperda (Sf9) cells in a time- and concentration-dependent manner under ultraviolet A (UV-A) light for 3 min. The inverted microscope revealed that cells treated with I34 swelled, the membrane was ruptured, and apoptotic bodies appeared. The flow cytometry detected that I34 could induce apoptosis of Sf9 cells, increase the level of intracellular reactive oxygen species (ROS), decrease the mitochondrial membrane potential, and block cell cycle arrest in the G2/M phase. Transmission electron microscopy detected cell mitochondrial cristae damage, matrix degradation, and mitochondrial vacuolation. Further enzyme activity detection revealed that the enzyme activities of apoptosis-related proteins caspase-3 and caspase-9 increased significantly (p < 0.05). Finally, Western blotting analysis detected that the phosphorylation level of Akt and Bad and the expression of the apoptosis inhibitor protein Bcl-XL were inhibited, cleaved-PARP and P53 were increased, and cytochrome C was released from the mitochondria into the cytoplasm. Moreover, under UV-A irradiation, I34 promoted the increase in ROS in Sf9 cells, activated the mitochondrial apoptotic signal transduction pathway, and finally, inhibited cell proliferation. Thus, novel furanocoumarins exhibit a potential application prospect as a biochemical pesticide. Full article
Show Figures

Figure 1

Back to TopTop