scholarly journals Hydroxychloroquine synergizes with the PI3K inhibitor BKM120 to exhibit antitumor efficacy independent of autophagy

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Xin Peng ◽  
Shaolu Zhang ◽  
Wenhui Jiao ◽  
Zhenxing Zhong ◽  
Yuqi Yang ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Cell Biology ◽  
Molecular Mechanisms ◽  
Critical Role ◽  
Single Agent ◽  
Antitumor Efficacy ◽  
Antitumor Effects ◽  
Autophagy Inhibitor

Abstract Background The critical role of phosphoinositide 3-kinase (PI3K) activation in tumor cell biology has prompted massive efforts to develop PI3K inhibitors (PI3Kis) for cancer therapy. However, recent results from clinical trials have shown only a modest therapeutic efficacy of single-agent PI3Kis in solid tumors. Targeting autophagy has controversial context-dependent effects in cancer treatment. As a FDA-approved lysosomotropic agent, hydroxychloroquine (HCQ) has been well tested as an autophagy inhibitor in preclinical models. Here, we elucidated the novel mechanism of HCQ alone or in combination with PI3Ki BKM120 in the treatment of cancer. Methods The antitumor effects of HCQ and BKM120 on three different types of tumor cells were assessed by in vitro PrestoBlue assay, colony formation assay and in vivo zebrafish and nude mouse xenograft models. The involved molecular mechanisms were investigated by MDC staining, LC3 puncta formation assay, immunofluorescent assay, flow cytometric analysis of apoptosis and ROS, qRT-PCR, Western blot, comet assay, homologous recombination (HR) assay and immunohistochemical staining. Results HCQ significantly sensitized cancer cells to BKM120 in vitro and in vivo. Interestingly, the sensitization mediated by HCQ could not be phenocopied by treatment with other autophagy inhibitors (Spautin-1, 3-MA and bafilomycin A1) or knockdown of the essential autophagy genes Atg5/Atg7, suggesting that the sensitizing effect might be mediated independent of autophagy status. Mechanistically, HCQ induced ROS production and activated the transcription factor NRF2. In contrast, BKM120 prevented the elimination of ROS by inactivation of NRF2, leading to accumulation of DNA damage. In addition, HCQ activated ATM to enhance HR repair, a high-fidelity repair for DNA double-strand breaks (DSBs) in cells, while BKM120 inhibited HR repair by blocking the phosphorylation of ATM and the expression of BRCA1/2 and Rad51. Conclusions Our study revealed that HCQ and BKM120 synergistically increased DSBs in tumor cells and therefore augmented apoptosis, resulting in enhanced antitumor efficacy. Our findings provide a new insight into how HCQ exhibits antitumor efficacy and synergizes with PI3Ki BKM120, and warn that one should consider the “off target” effects of HCQ when used as autophagy inhibitor in the clinical treatment of cancer.

scholarly journals Hydroxychloroquine Synergizes With The PI3K Inhibitor BKM120 to Exhibit Antitumor Efficacy Independent of Autophagy

2021 ◽  
Author(s):  
Xin Peng ◽  
Shaolu Zhang ◽  
Wenhui Jiao ◽  
Zhenxing Zhong ◽  
Yuqi Yang ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Cell Biology ◽  
Molecular Mechanisms ◽  
Critical Role ◽  
Single Agent ◽  
Antitumor Efficacy ◽  
Antitumor Effects ◽  
Autophagy Inhibitor

Abstract Background: The critical role of phosphoinositide 3-kinase (PI3K) activation in tumor cell biology has prompted massive efforts to develop PI3K inhibitors (PI3Kis) for cancer therapy. However, recent results from clinical trials have shown only a modest therapeutic efficacy of single-agent PI3Kis in solid tumors. Targeting autophagy has controversial context-dependent effects in cancer treatment. As a FDA-approved lysosomotropic agent, hydroxychloroquine (HCQ) has been well tested as an autophagy inhibitor in preclinical models. Here, we elucidated the novel mechanism of HCQ alone or in combination with PI3Ki BKM120 in the treatment of cancer.Methods: The antitumor effects of HCQ and BKM120 on three different types of tumor cells were assessed by in vitro PrestoBlue assay, colony formation assay and in vivo zebrafish and nude mouse xenograft models. The involved molecular mechanisms were investigated by MDC staining, LC3 puncta formation assay, immunofluorescent assay, flow cytometric analysis of apoptosis and ROS, qRT-PCR, Western blot, comet assay, homologous recombination (HR) assay and immunohistochemical staining. Results: HCQ significantly sensitized cancer cells to BKM120 in vitro and in vivo. Interestingly, the sensitization mediated by HCQ could not be phenocopied by treatment with other autophagy inhibitors (Spautin-1, 3-MA and bafilomycin A1) or knockdown of the essential autophagy genes Atg5/Atg7, suggesting that the sensitizing effect might be mediated independent of autophagy status. Mechanistically, HCQ induced ROS production and activated the transcription factor NRF2. In contrast, BKM120 prevented the elimination of ROS by inactivation of NRF2, leading to accumulation of DNA damage. In addition, HCQ activated ATM to enhance HR repair, a high-fidelity repair for DNA double-strand breaks (DSBs) in cells, while BKM120 inhibited HR repair by blocking the phosphorylation of ATM and the expression of BRCA1/2 and Rad51. Conclusions: Our study revealed that HCQ and BKM120 synergistically increased DSBs in tumor cells and therefore augmented apoptosis, resulting in enhanced antitumor efficacy. Our findings provide a new insight into how HCQ exhibits antitumor efficacy and synergizes with PI3Ki BKM120, and warn that one should consider the “off target” effects of HCQ when used as autophagy inhibitor in the clinical treatment of cancer.

IITZ-01, a novel potent lysosomotropic autophagy inhibitor, has single-agent antitumor efficacy in triple-negative breast cancer in vitro and in vivo

Oncogene ◽  
2018 ◽  
Vol 38 (4) ◽  
pp. 581-595 ◽  
Author(s):  
Lalita Guntuku ◽  
Jagadeesh Kumar Gangasani ◽  
Dinesh Thummuri ◽  
Roshan M. Borkar ◽  
Bramanandam Manavathi ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Triple Negative Breast Cancer ◽  
Triple Negative ◽  
Single Agent ◽  
Antitumor Efficacy ◽  
Autophagy Inhibitor

scholarly journals The impact of FGF19/FGFR4 signaling inhibition in antitumor activity of multi-kinase inhibitors in hepatocellular carcinoma

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hiroaki Kanzaki ◽  
Tetsuhiro Chiba ◽  
Junjie Ao ◽  
Keisuke Koroki ◽  
Kengo Kanayama ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Molecular Mechanisms ◽  
Kinase Inhibitors ◽  
Progression Free Survival ◽  
Erk Signaling ◽  
Enzyme Linked Immunosorbent Assay ◽  
Antitumor Effects ◽  
The Impact

AbstractFGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19high (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19low (n = 105) patients, there were no significant differences between FGF19high (n = 21) and FGF19low (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.

scholarly journals Pancreatic tumor cell metastasis is restricted by MT1-MMP binding protein MTCBP-1

2018 ◽  
Vol 218 (1) ◽  
pp. 317-332 ◽  
Author(s):  
Li Qiang ◽  
Hong Cao ◽  
Jing Chen ◽  
Shaun G. Weller ◽  
Eugene W. Krueger ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Pancreatic Tumor ◽  
Binding Protein ◽  
Critical Role ◽  
Inverse Correlation ◽  
Pancreatic Tumors ◽  
Matrix Remodeling ◽  
Peripheral Tissues

The process by which tumor cells mechanically invade through surrounding stroma into peripheral tissues is an essential component of metastatic dissemination. The directed recruitment of the metalloproteinase MT1-MMP to invadopodia plays a critical role in this invasive process. Here, we provide mechanistic insight into MT1-MMP cytoplasmic tail binding protein 1 (MTCBP-1) with respect to invadopodia formation, matrix remodeling, and invasion by pancreatic tumor cells. MTCBP-1 localizes to invadopodia and interacts with MT1-MMP. We find that this interaction displaces MT1-MMP from invadopodia, thereby attenuating their number and function and reducing the capacity of tumor cells to degrade matrix. Further, we observe an inverse correlation between MTCBP-1 and MT1-MMP expression both in cultured cell lines and human pancreatic tumors. Consistently, MTCBP-1–expressing cells show decreased ability to invade in vitro and metastasize in vivo. These findings implicate MTCBP-1 as an inhibitor of the metastatic process.

scholarly journals Assessment of phagocytic activity in live macrophages-tumor cells co-cultures by Confocal and Nomarski Microscopy

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Dalia Martinez-Marin ◽  
Courtney Jarvis ◽  
Thomas Nelius ◽  
Stéphanie Filleur
Keyword(s):  
Tumor Microenvironment ◽  
Tumor Cells ◽  
Phagocytic Activity ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Functional Assay ◽  
Loss Of Function ◽  
Multiple Cancer

Abstract Macrophages have been recognized as the main inflammatory component of the tumor microenvironment. Although often considered as beneficial for tumor growth and disease progression, tumor-associated macrophages have also been shown to be detrimental to the tumor depending on the tumor microenvironment. Therefore, understanding the molecular interactions between macrophages and tumor cells in relation to macrophages functional activities such as phagocytosis is critical for a better comprehension of their tumor-modulating action. Still, the characterization of these molecular mechanisms in vivo remains complicated due to the extraordinary complexity of the tumor microenvironment and the broad range of tumor-associated macrophage functions. Thus, there is an increasing demand for in vitro methodologies to study the role of cell–cell interactions in the tumor microenvironment. In the present study, we have developed live co-cultures of macrophages and human prostate tumor cells to assess the phagocytic activity of macrophages using a combination of Confocal and Nomarski Microscopy. Using this model, we have emphasized that this is a sensitive, measurable, and highly reproducible functional assay. We have also highlighted that this assay can be applied to multiple cancer cell types and used as a selection tool for a variety of different types of phagocytosis agonists. Finally, combining with other studies such as gain/loss of function or signaling studies remains possible. A better understanding of the interactions between tumor cells and macrophages may lead to the identification of new therapeutic targets against cancer.

scholarly journals Antitumor effects of the small molecule DMAMCL in neuroblastoma via suppressing aerobic glycolysis and targeting PFKL

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Simeng Zhang ◽  
Zhongyan Hua ◽  
Gen Ba ◽  
Ning Xu ◽  
Jianing Miao ◽  
...  
Keyword(s):  
Cell Death ◽  
Synergistic Effects ◽  
Aerobic Glycolysis ◽  
Single Agent ◽  
Molecular Compound ◽  
Dependent Manner ◽  
Antitumor Effects ◽  
Atp Production

Abstract Background Neuroblastoma (NB) is a common solid malignancy in children that is associated with a poor prognosis. Although the novel small molecular compound Dimethylaminomicheliolide (DMAMCL) has been shown to induce cell death in some tumors, little is known about its role in NB. Methods We examined the effect of DMAMCL on four NB cell lines (NPG, AS, KCNR, BE2). Cellular confluence, survival, apoptosis, and glycolysis were detected using Incucyte ZOOM, CCK-8 assays, Annexin V-PE/7-AAD flow cytometry, and Seahorse XFe96, respectively. Synergistic effects between agents were evaluated using CompuSyn and the effect of DMAMCL in vivo was evaluated using a xenograft mouse model. Phosphofructokinase-1, liver type (PFKL) expression was up- and down-regulated using overexpression plasmids or siRNA. Results When administered as a single agent, DMAMCL decreased cell proliferation in a time- and dose-dependent manner, increased the percentage of cells in SubG1 phase, and induced apoptosis in vitro, as well as inhibiting tumor growth and prolonging survival in tumor-bearing mice (NGP, BE2) in vivo. In addition, DMAMCL exerted synergistic effects when combined with etoposide or cisplatin in vitro and displayed increased antitumor effects when combined with etoposide in vivo compared to either agent alone. Mechanistically, DMAMCL suppressed aerobic glycolysis by decreasing glucose consumption, lactate excretion, and ATP production, as well as reducing the expression of PFKL, a key glycolysis enzyme, in vitro and in vivo. Furthermore, PFKL overexpression attenuated DMAMCL-induced cell death, whereas PFKL silencing promoted NB cell death. Conclusions The results of this study suggest that DMAMCL exerts antitumor effects on NB both in vitro and in vivo by suppressing aerobic glycolysis and that PFKL could be a potential target of DMAMCL in NB.

Kaposi sarcoma-associated herpesvirus (KSHV) induces heme oxygenase-1 expression and activity in KSHV-infected endothelial cells

Blood ◽  
2004 ◽  
Vol 103 (9) ◽  
pp. 3465-3473 ◽  
Author(s):  
Shane C. McAllister ◽  
Scott G. Hansen ◽  
Rebecca A. Ruhl ◽  
Camilo M. Raggo ◽  
Victor R. DeFilippis ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Heme Oxygenase ◽  
Cell Biology ◽  
Molecular Mechanisms ◽  
Expression Profiles ◽  
Kaposi Sarcoma ◽  
Heme Oxygenase 1 ◽  
Spindle Cell Proliferation

Abstract Kaposi sarcoma (KS) is the most common AIDS-associated malignancy and is characterized by angiogenesis and the presence of spindle cells. Kaposi sarcoma-associated herpesvirus (KSHV) is consistently associated with all clinical forms of KS, and in vitro infection of dermal microvascular endothelial cells (DMVECs) with KSHV recapitulates many of the features of KS, including transformation, spindle cell proliferation, and angiogenesis. To study the molecular mechanisms of KSHV pathogenesis, we compared the protein expression profiles of KSHV-infected and uninfected DMVECs. This comparison revealed that heme oxygenase-1 (HO-1), the inducible enzyme responsible for the rate-limiting step in heme catabolism, was up-regulated in infected endothelial cells. Recent evidence suggests that the products of heme catabolism have important roles in endothelial cell biology, including apoptosis and angiogenesis. Here we show that HO-1 mRNA and protein are up-regulated in KSHV-infected cultures. Comparison of oral and cutaneous AIDS-KS tissues with normal tissues revealed that HO-1 mRNA and protein were also up-regulated in vivo. Increased HO-1 enzymatic activity in vitro enhanced proliferation of KSHV-infected DMVECs in the presence of free heme. Treatment with the HO-1 inhibitor chromium mesoporphyrin IX abolished heme-induced proliferation. These data suggest that HO-1 is a potential therapeutic target for KS that warrants further study. (Blood. 2004;103: 3465-3473)

LncRNA MALAT1 exhibits positive effects on nucleus pulposus cell biology in vivo and in vitro by sponging miR-503

2020 ◽  
Author(s):  
Hongyu Zheng ◽  
Tingting Wang ◽  
Xiangmin Li ◽  
Wei He ◽  
Zhiqiang Gong ◽  
...  
Keyword(s):  
Nucleus Pulposus ◽  
Disc Degeneration ◽  
Cell Biology ◽  
Mapk Pathway ◽  
Critical Role ◽  
Mapk Signaling ◽  
Positive Effects ◽  
Lncrna Malat1

Abstract Background: Intervertebral disc degeneration (IDD) is characterized by the loss of nucleus pulposus cells (NPCs) and phenotypic abnormalities. Accumulating evidence suggests that long noncoding RNAs (lncRNAs) are involved in the pathogenesis of IDD. In this study, we aimed to investigate the functional effects of lncRNA MALAT1 on NPCs in IDD and the possible mechanism governing these effects. Results: We validated the decreased expression of MALAT1 in the IDD tissues, which was associated with decreased Collagen II and Aggrecan expression. In vitro, overexpressed MALAT1 could attenuate the effect of IL-1β on NPC proliferation, apoptosis, and Aggrecan degradation. In vivo, MALAT1 overexpression attenuated the severity of disc degeneration in IDD model rats. Our molecular study further demonstrated that MALAT1 could sponge miR-503, modulate the expression of miR-503, and activate downstream MAPK signaling pathways. The effects of MALAT1 on NPCs were partially reversed/aggregated by miR-503 mimics/inhibitor treatment. Conclusion: Our data suggested that the MALAT1-miR-503-MAPK pathway plays a critical role in NPCs, which may be a potential strategy for alleviating IDD.

scholarly journals Nano-encapsulated tryptanthrin derivative for combined anticancer therapy via inhibiting indoleamine 2,3-dioxygenase and inducing immunogenic cell death

Nanomedicine ◽  
2019 ◽  
Vol 14 (18) ◽  
pp. 2423-2440 ◽  
Author(s):  
Canyu Yang ◽  
Bing He ◽  
Qiang Zheng ◽  
Dakuan Wang ◽  
Mengmeng Qin ◽  
...  
Keyword(s):  
Cell Death ◽  
Single Agent ◽  
Tumor Burden ◽  
Antitumor Efficacy ◽  
In Vivo Studies ◽  
Immunogenic Cell Death ◽  
Indoleamine 2,3 Dioxygenase ◽  
Tumor Tissues

Aim: We developed a polycaprolactone-based nanoparticle (NP) to encapsulate tryptanthrin derivative CY-1-4 and evaluated its antitumor efficacy. Materials & methods: CY-1-4 NPs were prepared and evaluated for their cytotoxicity and associated mechanisms, indoleamine 2,3-dioxygenase (IDO)-inhibitory ability, immunogenic cell death (ICD)-inducing ability and antitumor efficacy. Results: CY-1-4 NPs were 123 nm in size. In vitro experiments indicated that they could both induce ICD and inhibit IDO. In vivo studies indicated that a medium dose reduced 58% of the tumor burden in a B16-F10-bearing mouse model, decreased IDO expression in tumor tissues and regulated lymphocytes subsets in spleen and tumors. Conclusion: CY-1-4 is a potential antitumor candidate that could act as a single agent with combined functions of IDO inhibition and ICD induction.

scholarly journals Tumor quiescence: elevating SOX2 in diverse tumor cell types downregulates a broad spectrum of the cell cycle machinery and inhibits tumor growth

BMC Cancer ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ethan P. Metz ◽  
Erin L. Wuebben ◽  
Phillip J. Wilder ◽  
Jesse L. Cox ◽  
Kaustubh Datta ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Tumor Growth ◽  
Tumor Cell ◽  
Tumor Cells ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Cell Cycle Machinery

Abstract Background Quiescent tumor cells pose a major clinical challenge due to their ability to resist conventional chemotherapies and to drive tumor recurrence. Understanding the molecular mechanisms that promote quiescence of tumor cells could help identify therapies to eliminate these cells. Significantly, recent studies have determined that the function of SOX2 in cancer cells is highly dose dependent. Specifically, SOX2 levels in tumor cells are optimized to promote tumor growth: knocking down or elevating SOX2 inhibits proliferation. Furthermore, recent studies have shown that quiescent tumor cells express higher levels of SOX2 compared to adjacent proliferating cells. Currently, the mechanisms through which elevated levels of SOX2 restrict tumor cell proliferation have not been characterized. Methods To understand how elevated levels of SOX2 restrict the proliferation of tumor cells, we engineered diverse types of tumor cells for inducible overexpression of SOX2. Using these cells, we examined the effects of elevating SOX2 on their proliferation, both in vitro and in vivo. In addition, we examined how elevating SOX2 influences their expression of cyclins, cyclin-dependent kinases (CDKs), and p27Kip1. Results Elevating SOX2 in diverse tumor cell types led to growth inhibition in vitro. Significantly, elevating SOX2 in vivo in pancreatic ductal adenocarcinoma, medulloblastoma, and prostate cancer cells induced a reversible state of tumor growth arrest. In all three tumor types, elevation of SOX2 in vivo quickly halted tumor growth. Remarkably, tumor growth resumed rapidly when SOX2 returned to endogenous levels. We also determined that elevation of SOX2 in six tumor cell lines decreased the levels of cyclins and CDKs that control each phase of the cell cycle, while upregulating p27Kip1. Conclusions Our findings indicate that elevating SOX2 above endogenous levels in a diverse set of tumor cell types leads to growth inhibition both in vitro and in vivo. Moreover, our findings indicate that SOX2 can function as a master regulator by controlling the expression of a broad spectrum of cell cycle machinery. Importantly, our SOX2-inducible tumor studies provide a novel model system for investigating the molecular mechanisms by which elevated levels of SOX2 restrict cell proliferation and tumor growth.

Sign in / Sign up

Export Citation Format

Share Document