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AIDS (London, England) Apr 2024Some drugs that augment cell-intrinsic defenses or modulate cell death/survival pathways have been reported to selectively kill cells infected with HIV or SIV, but...
OBJECTIVES
Some drugs that augment cell-intrinsic defenses or modulate cell death/survival pathways have been reported to selectively kill cells infected with HIV or SIV, but comparative studies are lacking. We hypothesized that these drugs may differ in their ability to kill cells infected with intact and defective proviruses.
DESIGN
To investigate this hypothesis, drugs were tested ex vivo on Peripheral Blood Mononuclear Cells (PBMC) from nine ART-suppressed individuals.
METHODS
We tested drugs currently in clinical use or human trials, including auranofin (p53 modulator), interferon alpha2A, interferon gamma, acitretin (RIG-I inducer), GS-9620/vesatolimod (TLR7 agonist), nivolumab (PD-1 blocker), obatoclax (Bcl-2 inhibitor), birinapant (IAP inhibitor), bortezomib (proteasome inhibitor), and INK128/sapanisertib (mTOR[c]1/2 inhibitor). After six days of treatment, we measured cell counts/viabilities and quantified levels of total, intact, and defective HIV DNA by droplet digital PCR (Intact Proviral DNA Assay).
RESULTS
Obatoclax reduced intact HIV DNA (median = 27-30% of DMSO) but not defective or total HIV DNA. Other drugs showed no statistically significant effects.
CONCLUSIONS
Obatoclax and other Bcl-2 inhibitors deserve further study in combination therapies aimed at reducing the intact HIV reservoir in order to achieve a functional cure and/or reduce HIV-associated immune activation.
PubMed: 38626436
DOI: 10.1097/QAD.0000000000003908 -
Journal of Translational Medicine Mar 2024Colorectal cancer (CRC) is the third most prevalent cancer globally, and liver metastasis (CRLM) is the primary cause of death. Hence, it is essential to discover novel...
BACKGROUND
Colorectal cancer (CRC) is the third most prevalent cancer globally, and liver metastasis (CRLM) is the primary cause of death. Hence, it is essential to discover novel prognostic biomarkers and therapeutic drugs for CRLM.
METHODS
This study developed two liver metastasis-associated prognostic signatures based on differentially expressed genes (DEGs) in CRLM. Additionally, we employed an interpretable deep learning model utilizing drug sensitivity databases to identify potential therapeutic drugs for high-risk CRLM patients. Subsequently, in vitro and in vivo experiments were performed to verify the efficacy of these compounds.
RESULTS
These two prognostic models exhibited superior performance compared to previously reported ones. Obatoclax, a BCL-2 inhibitor, showed significant differential responses between high and low risk groups classified by prognostic models, and demonstrated remarkable effectiveness in both Transwell assay and CT26 colorectal liver metastasis mouse model.
CONCLUSIONS
This study highlights the significance of developing specialized prognostication approaches and investigating effective therapeutic drugs for patients with CRLM. The application of a deep learning drug response model provides a new drug discovery strategy for translational medicine in precision oncology.
Topics: Animals; Mice; Humans; Precision Medicine; Prognosis; Liver Neoplasms; Drug Discovery; Colorectal Neoplasms
PubMed: 38555418
DOI: 10.1186/s12967-024-05127-5 -
Journal of Biomolecular Structure &... Dec 2023Due to the multifarious nature of cancer, finding a single definitive cure for this dreadful disease remains an elusive challenge. The dysregulation of the apoptotic...
Due to the multifarious nature of cancer, finding a single definitive cure for this dreadful disease remains an elusive challenge. The dysregulation of the apoptotic pathway or programmed cell death, governed by the Bcl-2 family of proteins plays a crucial role in cancer development and progression. Bcl-B stands out as a unique anti-apoptotic protein from the Bcl-2 family that selectively binds to Bax which inhibits its pro-apoptotic function. Although several inhibitors are reported for Bcl-2 family proteins, no specific inhibitors are available against the anti-apoptotic Bcl-B protein. This study aims to address this research gap by using virtual screening of an in-house library of phytochemicals from seven anti-cancer medicinal plants to identify lead molecules against Bcl-B protein. Through pharmacokinetic analysis and molecular docking studies, we identified three lead candidates (Enterolactone, Piperine, and Protopine) based on appreciable drug-likeliness, ADME properties, and binding affinity values. The identified molecules also exhibited specific interactions with critical amino acid residues of the binding cleft, highlighting their potential as lead candidates. Finally, molecular dynamics simulations and MM/PBSA based binding free energy analysis revealed that Enterolactone (CID_114739) and Piperine (CID_638024) molecules were on par with Obatoclax (CID_11404337), which is a known inhibitor of the Bcl-2 family proteins.Communicated by Ramaswamy H. Sarma.
PubMed: 38111145
DOI: 10.1080/07391102.2023.2295385 -
IScience Oct 2023We identified cytoprotective small molecules (CSMs) by a cell-based high-throughput screening of Bax inhibitors. Through a medicinal chemistry program, M109S was...
We identified cytoprotective small molecules (CSMs) by a cell-based high-throughput screening of Bax inhibitors. Through a medicinal chemistry program, M109S was developed, which is orally bioactive and penetrates the blood-brain/retina barriers. M109S protected retinal cells in ocular disease mouse models. M109S directly interacted with Bax and inhibited the conformational change and mitochondrial translocation of Bax. M109S inhibited ABT-737-induced apoptosis both in Bax-only and Bak-only mouse embryonic fibroblasts. M109S also inhibited apoptosis induced by staurosporine, etoposide, and obatoclax. M109S decreased maximal mitochondrial oxygen consumption rate and reactive oxygen species production, whereas it increased glycolysis. These effects on cellular metabolism may contribute to the cytoprotective activity of M109S. M109S is a novel small molecule protecting cells from mitochondria-dependent apoptosis both and . M109S has the potential to become a research tool for studying cell death mechanisms and to develop therapeutics targeting mitochondria-dependent cell death pathway.
PubMed: 37841588
DOI: 10.1016/j.isci.2023.107916 -
ACS Infectious Diseases Nov 2023The implementation of combined antiretroviral therapy (cART) has rendered HIV-1 infection clinically manageable and efficiently improves the quality of life for patients...
The implementation of combined antiretroviral therapy (cART) has rendered HIV-1 infection clinically manageable and efficiently improves the quality of life for patients with AIDS. However, the persistence of a latent HIV-1 reservoir is a major obstacle to achieving a cure for AIDS. A "shock and kill" strategy aims to reactivate latent HIV and then kill it by the immune system or cART drugs. To date, none of the LRA candidates has yet demonstrated effectiveness in achieving a promising functional cure. Interestingly, the phosphorylation and activation of antiapoptotic Bcl-2 protein induce resistance to apoptosis during HIV-1 infection and the reactivation of HIV-1 latency in central memory CD4 T cells from HIV-1-positive patients. Therefore, a Bcl-2 antagonist might be an effective LRA candidate for HIV-1 cure. In this study, we reported that a pan-Bcl-2 antagonist obatoclax induces HIV-1 reactivation in latently infected cell lines and in PBMCs/CD4 T cells of HIV-infected individuals . Obatoclax promotes HIV-1 transcriptional initiation and elongation by regulating the NF-κB pathway. Obatoclax activates caspase 8 and does not induce the phosphorylation of the antiapoptotic protein Bcl-2 in latent HIV-1 infected cell lines. More importantly, it preferentially induces apoptosis in latently infected cells. In addition, obatoclax exhibited potent anti-HIV-1 activity on target cells. The abilities to reactivate latent HIV-1 reservoirs, inhibit HIV-1 infection, and induce HIV-1 latent cell apoptosis make obatoclax worth investigating for development as an ideal LRA for use in the "shock and kill" approach.
Topics: Humans; NF-kappa B; HIV Infections; Virus Activation; Virus Latency; HIV-1; Acquired Immunodeficiency Syndrome; Quality of Life; CD4-Positive T-Lymphocytes; Apoptosis
PubMed: 37796279
DOI: 10.1021/acsinfecdis.3c00218 -
Toxicological Research Oct 2023Autophagy play contradictory roles in cellular transformation. We previously found that the knockout (KO) of autophagy-related 5 (Atg5), which is essential for...
UNLABELLED
Autophagy play contradictory roles in cellular transformation. We previously found that the knockout (KO) of autophagy-related 5 (Atg5), which is essential for autophagy, leads to the malignant transformation of NIH 3T3 cells. In this study, we explored the mechanism by which autophagy contributes to this malignant transformation using two transformed cell lines, Atg5 KO and Ras-NIH 3T3. Monomeric red fluorescent protein-green fluorescent protein-light chain 3 reporter and Cyto-ID staining revealed that Ras-NIH 3T3 cells exhibited higher basal autophagy activity than NIH 3T3 cells. Additionally, transformed cells, regardless of their Atg5 KO status, were more sensitive to autophagy inhibitors (SBI-0206965, chloroquine, and obatoclax) than the untransformed NIH 3T3 cells, suggesting that the transformed cells are more autophagy-dependent than the normal cells. Loss of Atg5 improved the cell viability and mobility, especially in Ras-NIH 3T3 cells. Furthermore, we discovered that autophagy was alternatively induced in a Rab9-dependent manner in Ras-NIH 3T3 and NIH 3T3/Atg5 KO cells. In particular, Atg5 KO cells showed reduced mTOR-mediated phosphorylation of Akt (pAkt S473), indicating the mTOR-independent occurrence of alternative autophagy in Atg5 KO cells. Therefore, our study provides evidence that alternative autophagy may contribute to tumorigenesis in cells with an impaired Atg5-dependent autophagy pathway.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s43188-023-00191-3.
PubMed: 37779593
DOI: 10.1007/s43188-023-00191-3 -
Cells Sep 2023Aging is associated with the disruption of protein homeostasis and causally contributes to multiple diseases, including amyotrophic lateral sclerosis (ALS). One strategy...
Aging is associated with the disruption of protein homeostasis and causally contributes to multiple diseases, including amyotrophic lateral sclerosis (ALS). One strategy for restoring protein homeostasis and protecting neurons against age-dependent diseases such as ALS is to de-repress autophagy. BECN1 is a master regulator of autophagy; however, is repressed by BCL2 via a BH3 domain-mediated interaction. We used an induced pluripotent stem cell model of ALS caused by mutant FUS to identify a small molecule BH3 mimetic that disrupts the BECN1-BCL2 interaction. We identified obatoclax as a brain-penetrant drug candidate that rescued neurons at nanomolar concentrations by reducing cytoplasmic FUS levels, restoring protein homeostasis, and reducing degeneration. Proteomics data suggest that obatoclax protects neurons via multiple mechanisms. Thus, obatoclax is a candidate for repurposing as a possible ALS therapeutic and, potentially, for other age-associated disorders linked to defects in protein homeostasis.
Topics: Humans; Amyotrophic Lateral Sclerosis; Motor Neurons; Induced Pluripotent Stem Cells; Mutation; Autophagy; Phenotype; Proto-Oncogene Proteins c-bcl-2; RNA-Binding Protein FUS
PubMed: 37759469
DOI: 10.3390/cells12182247 -
Neuro-oncology Advances 2023IDH-wildtype glioblastoma (GBM) is a highly malignant primary brain tumor with a median survival of 15 months after standard of care, which highlights the need for...
BACKGROUND
IDH-wildtype glioblastoma (GBM) is a highly malignant primary brain tumor with a median survival of 15 months after standard of care, which highlights the need for improved therapy. Personalized combination therapy has shown to be successful in many other tumor types and could be beneficial for GBM patients.
METHODS
We performed the largest drug combination screen to date in GBM, using a high-throughput effort where we selected 90 drug combinations for their activity onto 25 patient-derived GBM cultures. 43 drug combinations were selected for interaction analysis based on their monotherapy efficacy and were tested in a short-term (3 days) as well as long-term (18 days) assay. Synergy was assessed using dose-equivalence and multiplicative survival metrics.
RESULTS
We observed a consistent synergistic interaction for 15 out of 43 drug combinations on patient-derived GBM cultures. From these combinations, 11 out of 15 drug combinations showed a longitudinal synergistic effect on GBM cultures. The highest synergies were observed in the drug combinations Lapatinib with Thapsigargin and Lapatinib with Obatoclax Mesylate, both targeting epidermal growth factor receptor and affecting the apoptosis pathway. To further elaborate on the apoptosis cascade, we investigated other, more clinically relevant, apoptosis inducers and observed a strong synergistic effect while combining Venetoclax (BCL targeting) and AZD5991 (MCL1 targeting).
CONCLUSIONS
Overall, we have identified via a high-throughput drug screening several new treatment strategies for GBM. Moreover, an exceptionally strong synergistic interaction was discovered between kinase targeting and apoptosis induction which is suitable for further clinical evaluation as multi-targeted combination therapy.
PubMed: 37455945
DOI: 10.1093/noajnl/vdad073 -
American Journal of Cancer Research 2023Immunocharacteristics-based typing strategies can be used to reflect the similar status of tumors. Therefore, we aimed to demonstrate whether the immune subtypes of GBM...
Immunocharacteristics-based typing strategies can be used to reflect the similar status of tumors. Therefore, we aimed to demonstrate whether the immune subtypes of GBM have independent prognostic efficacy and whether these subtypes can be used as clinical guidance for predicting the progression of GBM and determining drug sensitivity. In this study, we found that patients with GBM were divided into three conserved immune-related subtypes based on the infiltration level of immune cells, including immunosuppressed, moderate immunoactivity, and high immunoactivity. Regarding the relevant clinical significance, the high immunoactivity in GBM indicates the worst survival, which exhibited the highest levels of oncogenic activity, including angiogenesis, tumor-associated macrophages and tumor-associated fibroblasts, indicated worst survival. The immunosuppressive subtype of GBM was more likely to carry epidermal growth factor receptor mutations and MGMT methylation, and belong to the classical and proneural subtypes; however, but the high immunoactivity subtype was not. The immune subtype-specific transcription factors (TFs) regulatory network indicates that specific TFs drive the construction of each immune subtype, and that these subtype-specific TFs are more prone to internal TFs regulation. Furthermore, the immunosuppressed and moderate immunoactivity subtypes were significantly correlated with the drugs sensitivity, whereas the high immunoactivity subtype was not, indicating that GBMs with high immunoactivity were refractory. We also found that obatoclax mesylate, NPK76-II-72-1, gemcitabine, TAK-715 are potential drugs for the treatment of refractory GBM based on drug sensitivity models of different immune subtypes. Therefore, we demonstrated that the immune subtypes of GBM have independent prognostic efficacy and can be used as clinical guidance for predicting the progression of GBM and drug sensitivity. Most importantly, this study is expected to provide a pathway for the development of effective drugs for treatment of refractory GBM.
PubMed: 37168341
DOI: No ID Found -
Medical Oncology (Northwood, London,... May 2023The present study reports anticancer and antioxidant activities of Callistemon lanceolatus bark extracts. Anticancer activity was studied against MDA-MB-231 cells....
The present study reports anticancer and antioxidant activities of Callistemon lanceolatus bark extracts. Anticancer activity was studied against MDA-MB-231 cells. Antioxidant assessment of the chloroform and methanol extracts showed considerable free radical scavenging, metal ion chelating, and reducing power potential. Chloroform extract exhibited potent inhibition of cancer cell proliferation in MTT assay (IC 9.6 μg/ml) and promoted programmed cell death. Reactive oxygen species (ROS) generation, mitochondria membrane potential (MMP) disruption ability, and nuclear morphology changes were studied using H-DCFDA, JC-1, and Hoechst dyes, respectively, using confocal microscopy. Apoptotic cells exhibited fragmented nuclei, increased ROS generation, and altered MMP in dose- and time-dependent manner. Chloroform extract upregulated the BAX-1 and CASP3 mRNA expression coupled with downregulation of BCL-2 gene. Further, in silico docking of phytochemicals present in C. lanceolatus with anti-apoptotic Bcl-2 protein endorsed apoptosis by its inhibition and thus corroborated the experimental findings. Obatoclax, a known inhibitor of Bcl-2 was used as a reference compounds.
Topics: Humans; Antioxidants; Reactive Oxygen Species; Plant Extracts; Chloroform; Plant Bark; Apoptosis; Cell Proliferation; Proto-Oncogene Proteins c-bcl-2; Cell Line, Tumor
PubMed: 37156972
DOI: 10.1007/s12032-023-02035-4