scholarly journals The Combination of CUDC-907 and Gilteritinib Shows Promising Antileukemic Activity in Vitro and In Vivo in Preclinical Models of FLT3-ITD AML

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 1262-1262
Author(s):  
Tristan Knight ◽  
Xinan Qiao ◽  
Jun Ma ◽  
Holly Edwards ◽  
Lisa Polin ◽  
...  
Keyword(s):  
Combination Therapy ◽  
Mouse Model ◽  
Cell Lines ◽  
Vehicle Control ◽  
Antileukemic Activity ◽  
Oral Gavage ◽  
In Vivo Efficacy ◽  
Flt3 Expression

Introduction FMS-like tyrosine kinase 3 internal tandem duplication (FLT3-ITD) mutations are found in approximately one quarter of acute myeloid leukemia (AML) cases. Its presence results in constitutive activation of the FLT3 receptor tyrosine kinase and its downstream growth/pro-survival pathways including MAPK/ERK, PI3K/AKT, and JAK/STAT, and confers a poor prognosis. Gilteritinib is a selective inhibitor of FLT3 recently approved by the Food and Drug Administration for treatment of patients with relapsed/refractory AML and a FLT3 mutation. However, gilteritinib exposure induces upregulation of FLT3 - a mechanism of resistance. Previously, we showed that CUDC-907, a dual PI3K/histone deacetylase inhibitor, downregulates FLT3 expression (Li X, et al. Haematologica. 2019; epub ahead of print). We therefore hypothesized that combining CUDC-907 with gilteritinib would abrogate FLT3 upregulation and expression, resulting in synergistic antileukemic activities against FLT3-mutated AML. Methods FLT3-ITD AML cell lines and primary patient samples were treated with gilteritinib or CUDC-907, alone or in combination at clinically achievable concentrations, and subjected to annexin V/propidium iodide staining and flow cytometry analysis to quantify apoptosis. Protein levels of FLT3, Bcl-2 family proteins, and key components of the MAPK/ERK, PI3K/AKT, and JAK/STAT pathways were examined using western blotting. The impact of the observed alterations upon apoptosis were confirmed via overexpression, knockdown, and targeted inhibitor experiments. Real-time RT-PCR was used to determine FLT3 transcript levels. The FLT3-ITD AML cell line MV4-11 was used to generate a xenograft mouse model to assess in vivo efficacy of the two agents. Results CUDC-907 and gilteritinib demonstrated potent synergistic antileukemic effects in FLT3-ITD AML cell lines in vitro and patient samples ex vivo, with combined therapy. CUDC-907 abolished gilteritinib-induced expression of FLT3 in both cell lines and primary patient samples. Gilteritinib treatment reduced p-AKT, p-S6, and p-STAT5 and increased p-ERK, while CUDC-907 reduced p-AKT and p-ERK, and upregulated p-STAT5. The combination of gilteritinib and CUDC-907 decreased not only p-AKT and p-S6, but also p-ERK and p-STAT5. Targeted inhibition of ERK and JAK2/STAT5 signaling by SCH772984 and AZD1480, respectively, confirmed their roles in resistance to gilteritinib and CUDC-907 monotherapies, respectively. Combined gilteritinib and CUDC-907 treatment reduced expression of the anti-apoptotic BCL-2 family member Mcl-1 and increased expression of the pro-apoptotic protein Bim. MCL-1 overexpression and BIM knockdown partially rescued FLT3-ITD AML cells upon drug treatment, confirming their role in the antileukemic activity of combined gilteritinib and CUDC-907. To determine in vivo efficacy of the two agents, NSGS mice were injected with MV4-11 cells. Three days later, the mice were randomized into vehicle control (n=5), 40 mg/kg gilteritinib (oral gavage; n=5), 100 mg/kg CUDC-907 (oral gavage; n=5) or combination (40 mg/kg gilteritinib + 100 mg/kg CUDC-907; n=6) groups. CUDC-907 was given daily for 5 days on, 2 days off, for a total of 4 cycles. Gilteritinib was administered daily for 28 days. Both agents were well tolerated; maximal weight loss was 5.5%, 0.9%, and 6.7% in the CUDC-907, gilteritinib, and combination groups, respectively. Median survival of mice in the vehicle control group was 43 days. Median survival in the CUDC-907 monotherapy and gilteritinib monotherapy arm was 40.5 days and 104 days, respectively. One mouse in the combination therapy arm died on day 138, while the remaining 5 mice in the combination therapy arm continue to survive, as of time of writing (day 168), and are asymptomatic (Figure 1). Conclusion We confirmed that the combination of CUDC-907 plus gilteritinib synergistically induces apoptosis in both FLT3-ITD AML cell lines and primary patient samples, and that gilteritinib-induced FLT3 expression is abolished by CUDC-907. Cooperative inhibition of the PI3K-AKT, JAK-STAT, and RAS-RAF pathways, as well as upregulation of Bim/downregulation of Mcl-1 all appear to contribute to this observed antileukemic synergy. Our cell line-derived xenograft mouse model provides strong evidence of in vivo efficacy and robust grounds for clinical translation of this therapeutic combination. Disclosures No relevant conflicts of interest to declare.

scholarly journals Venetoclax Synergistically Enhances the Antileukemic Activity of Imipridone ONC213, a Novel Imipridone ONC201 Analog, in Acute Myeloid Leukemia

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3936-3936
Author(s):  
Yongwei Su ◽  
Xinyu Li ◽  
Holly Edwards ◽  
Lisa Polin ◽  
Juiwanna Kushner ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Lines ◽  
Colony Formation ◽  
Myeloid Leukemia ◽  
Annexin V ◽  
Vehicle Control ◽  
Antileukemic Activity ◽  
Hematopoietic Progenitor

Abstract Although standard induction therapy initially elicits a promising response in the majority of acute myeloid leukemia (AML) patients, the majority relapse. Leukemia stem cells (LSCs) that survive chemotherapy are believed to be responsible for AML relapse. Therefore, new therapies that eliminate LSCs are desperately needed. ONC201 is a TRAIL inducer and the founding member of the imipridone family. It has been shown to induce apoptosis in LSCs (Ishizawa et al, Science Signaling. 2016; 9:ra17). ONC201 was chemically modified to increase the potency and selectivity against cancer cells, resulting in the new analog ONC213. In this study, we investigated the antileukemic activity and the underlying molecular mechanism of ONC213 in preclinical AML models. ONC213 activity in AML cell lines and primary AML patient samples was first tested in vitro. MTT assay results revealed that ONC213 IC50s ranged from 91.7 nM to 2.4 µM in AML cell lines and primary AML patient samples, which are achievable in vivo based on results from a PK study in mice (a single dose of 50 and 100 mg/kg ONC213 resulted in peak plasma concentrations of 3.7 μM and 8 μM, respectively). Annexin V/propidium iodide staining and flow cytometry analysis results showed variable responses for the AML cell lines tested. After 48 h treatment with 500 nM ONC213, striking induction of cell death in MOLM-13 and MV4-11 cells was detected (at least 72% Annexin V+ cells), while THP-1 and U937 cells showed little to no increase in Annexin V+ cells (6-11%). Similar results were obtained in primary AML patient samples. In contrast to the 48 h treatment of THP-1 and U937 cells, increasing the treatment duration to 120 h resulted in greater than 50% Annexin V+ cells, suggesting that a longer exposure time is necessary in some cell lines. In MV4-11 and MOLM-13 cells, initiation of cell death was detected 8 to 12 h post ONC213 treatment. Colony formation assays revealed that ONC213 treatment significantly reduced colony formation capacity of primary AML patient samples to less than 5% compared to vehicle control, while having no significant effect on normal hematopoietic progenitor cells. A primary AML patient sample was treated with or without ONC213 for 48 h, transplanted into NSG mice, and ten weeks later bone marrow was harvested and human CD45+ cells were measured. ONC213 treatment significantly reduced human AML engraftment compared to vehicle control (0.6% vs. 21.3%; p<0.05), demonstrating that ONC213 kills LSCs in vitro. Next, we examined in vivo efficacy of ONC213 against an AML cell line derived xenograft mouse model. MV4-11 cells were injected into NSGS mice through the tail vein. Three days post-injection, the mice were randomized into vehicle control or 125 mg/kg ONC213 cohorts (5 mice per cohort) and treated daily for 8 days. Modest weight loss was noted but was entirely manageable. ONC213 treatment extended the survival of mice by 88% (median survival 62 vs 33 days). Unlike ONC201, ONC213 treatment of AML cells did not increase the expression of TRAIL. Interestingly, RNAseq results showed that 500 nM ONC213 treatment for 48 h downregulated 33 mRNAs in the oxidative phosphorylation (OXPHOS) pathway, suggesting that ONC213 treatment decreases OXPHOS in AML cells. Thus far, six of the downregulated mRNAs (UQCRQ, SDHA, COX6C, NDUFS5, ATP5D, and NDUFB1) were verified by real-time RT-PCR after both 8 h and 48 h ONC213 treatment. LSCs have been shown to be highly reliant on OXPHOS, while normal hematopoietic stem cells and some bulk AML cells can switch to glycolysis for ATP production during times of OXPHOS inhibition. Thus, ONC213 may kill LSCs through inhibition of OXPHOS. In addition to downregulation of OXPHOS related genes, we found that ONC213 treatment downregulates Mcl-1. Since Mcl-1 mediates resistance to the promising Bcl-2-selective inhibitor ABT-199 (Venetoclax) and inhibition of Bcl-2 impairs OXPHOS, ONC213 would likely synergize with ABT-199 in AML cells. Indeed, combined treatment resulted in striking synergistic induction of apoptosis in both AML cell lines and primary patient samples. Enhanced cell death was detected 8 h post combination treatment in both MOLM-13 and MV4-11 cells. Results from colony formation assays revealed that the combination spares normal hematopoietic progenitor cells. Taken together, ONC213 is active as a single agent and in combination with ABT-199 in AML. Disclosures Allen: Oncoceutics: Employment. Stogniew:Oncoceutics: Employment. Prabhu:Oncoceutics: Employment. Ge:MEI Pharma: Research Funding.

Inhibition Of Wee1 Enhances The Anti-Leukemic Effects Of Antimetabolites In Vitro and In Vivo

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1281-1281
Author(s):  
James B. Ford ◽  
Susan Fosmire ◽  
Annemie van Linden ◽  
Dmitry Baturin ◽  
Christopher C. Porter
Keyword(s):  
Combination Therapy ◽  
Mouse Model ◽  
Acute Leukemia ◽  
Cell Lines ◽  
Conflicts Of Interest ◽  
Ex Vivo ◽  
Single Agent ◽  
Parp Cleavage

Abstract While some patients with acute leukemia are cured, for many subsets of patients current therapeutic strategies are not adequate. Novel therapeutic approaches are needed for patients with higher risk leukemias, including T-ALL and AML. We and others identified Wee1 as a potential target in AML cells using RNAi screening. We have validated chemosensitization to cytarabine by genetic and pharmacologic inhibition of Wee1 in AML cell lines and primary patient samples ex vivo. A Wee1 inhibitor, MK1775, is in clinical development. We sought to further our findings with a wider range of conventional anti-leukemia agents, to determine whether the functionality of p53 influences chemosensitization, and to determine the tolerability and efficacy of MK1775 in combination with cytarabine in a mouse model of leukemia. We have found that MK1775 synergistically inhibits proliferation of the T-ALL Jurkat cell line with several antimetabolite chemotherapeutics including cytarabine, 6-thioguanine, and methotrexate. In contrast, MK1775 does not sensitize Jurkats to doxorubicin or etoposide, suggesting specific sensitization to antimetabolites. The addition of MK1775 enhances the antimetabolite induced apoptosis, as measured by Annexin V/7-AAD staining, and PARP cleavage measured by Western blotting. As expected, the addition of MK1775 enhances DNA damage induced by cytarabine as measured by γH2AX staining and flow cytometry, although preliminary data suggest that this is not the only mechanism of enhanced cell death, as a substantial proportion of cleaved PARP+ cells does not stain for γH2AX. In addition, we have found that AML cell lines with both wild-type and mutated TP53 are sensitive to chemosensitization by Wee1 inhibition. Furthermore, in isogenic models of p53 dysfunction, we have found that the functionality of p53 does not influence chemosensitization. Lastly, in an aggressive mouse model of AML, we observed enhanced disease control and survival in mice treated with MK1775 and ARA-C as compared to ARA-C alone. Hematotoxicity associated with treatment was related to the duration of combination therapy, but was tolerated well with intermittent dosing. Taken together, these data indicate that Wee1 inhibition may enhance the efficacy of several clinically relevant anti-leukemia agents, particularly the antimetabolites, but not topoisomerase inhibitors. Further, they suggest caution about the use of p53 mutation as a biomarker predictive of response to Wee1 inhibition. Moreover, we show that the addition of MK1775 to cytarabine is tolerable and more effective than cytarabine alone in vivo. Ongoing studies are aimed at better understanding the mechanism of combinatorial effect and to determine whether combination therapy is more efficacious than single agent therapy in xenograft models of leukemia. These data provide justification for early phase clinical trials of MK1775 in combination with antimetabolites in patients with high risk acute leukemia. Disclosures: No relevant conflicts of interest to declare.

scholarly journals The SMAC mimetic LCL-161 selectively targets JAK2V617F mutant cells

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Brianna M. Craver ◽  
Thanh Kim Nguyen ◽  
Jenny Nguyen ◽  
Hellen Nguyen ◽  
Christy Huynh ◽  
...  
Keyword(s):  
Combination Therapy ◽  
Mouse Model ◽  
Characteristic Feature ◽  
Kinase Activity ◽  
Differential Sensitivity ◽  
Smac Mimetics ◽  
Smac Mimetic ◽  
Mutant Cells

Abstract Background Evasion from programmed cell death is a hallmark of cancer and can be achieved in cancer cells by overexpression of inhibitor of apoptosis proteins (IAPs). Second mitochondria-derived activator of caspases (SMAC) directly bind to IAPs and promote apoptosis; thus, SMAC mimetics have been investigated in a variety of cancer types. particularly in diseases with high inflammation and NFĸB activation. Given that elevated TNFα levels and NFĸB activation is a characteristic feature of myeloproliferative neoplasms (MPN), we investigated the effect of the SMAC mimetic LCL-161 on MPN cell survival in vitro and disease development in vivo. Methods To investigate the effect of the SMAC mimetic LCL-161 in vitro, we utilized murine and human cell lines to perform cell viability assays as well as primary bone marrow from mice or humans with JAK2V617F–driven MPN to interrogate myeloid colony formation. To elucidate the effect of the SMAC mimetic LCL-161 in vivo, we treated a JAK2V617F–driven mouse model of MPN with LCL-161 then assessed blood counts, splenomegaly, and myelofibrosis. Results We found that JAK2V617F-mutated cells are hypersensitive to the SMAC mimetic LCL-161 in the absence of exogenous TNFα. JAK2 kinase activity and NFĸB activation is required for JAK2V617F-mediated sensitivity to LCL-161, as JAK or NFĸB inhibitors diminished the differential sensitivity of JAK2V617F mutant cells to IAP inhibition. Finally, LCL-161 reduces splenomegaly and may reduce fibrosis in a mouse model of JAK2V617F-driven MPN. Conclusion LCL-161 may be therapeutically useful in MPN, in particular when exogenous TNFα signaling is blocked. NFĸB activation is a characteristic feature of JAK2V617F mutant cells and this sensitizes them to SMAC mimetic induced killing even in the absence of TNFα. However, when exogenous TNFα is added, NFĸB is activated in both mutant and wild-type cells, abolishing the differential sensitivity. Moreover, JAK kinase activity is required for the differential sensitivity of JAK2V617F mutant cells, suggesting that the addition of JAK2 inhibitors to SMAC mimetics would detract from the ability of SMAC mimetics to selectively target JAK2V617F mutant cells. Instead, combination therapy with other agents that reduce inflammatory cytokines but preserve JAK2 signaling in mutant cells may be a more beneficial combination therapy in MPN.

scholarly journals Radiosensitisation of Hepatocellular Carcinoma Cells by Vandetanib

Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1878 ◽  
Author(s):  
Sami Znati ◽  
Rebecca Carter ◽  
Marcos Vasquez ◽  
Adam Westhorpe ◽  
Hassan Shahbakhti ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Combination Therapy ◽  
Cell Lines ◽  
Radiation Treatment ◽  
Combined Treatment ◽  
New Combination ◽  
Migration And Invasion ◽  
Syngeneic Mouse Model

Hepatocellular Carcinoma (HCC) is increasing in incidence worldwide and requires new approaches to therapy. The combination of anti-angiogenic drug therapy and radiotherapy is one promising new approach. The anti-angiogenic drug vandetanib is a tyrosine kinase inhibitor of vascular endothelial growth factor receptor-2 (VEGFR-2) and RET proto-oncogene with radio-enhancement potential. To explore the benefit of combined vandetanib and radiotherapy treatment for HCC, we studied outcomes following combined treatment in pre-clinical models. Methods: Vandetanib and radiation treatment were combined in HCC cell lines grown in vitro and in vivo. In addition to 2D migration and clonogenic assays, the combination was studied in 3D spheroids and a syngeneic mouse model of HCC. Results: Vandetanib IC 50 s were measured in 20 cell lines and the drug was found to significantly enhance radiation cell kill and to inhibit both cell migration and invasion in vitro. In vivo, combination therapy significantly reduced cancer growth and improved overall survival, an effect that persisted for the duration of vandetanib treatment. Conclusion: In 2D and 3D studies in vitro and in a syngeneic model in vivo, the combination of vandetanib plus radiotherapy was more efficacious than either treatment alone. This new combination therapy for HCC merits evaluation in clinical trials.

scholarly journals Berberine reduces temozolomide resistance by inducing autophagy via the ERK1/2 signaling pathway in glioblastoma

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Huiling Qu ◽  
Xiaofu Song ◽  
Zhuyin Song ◽  
Xin Jiang ◽  
Xin Gao ◽  
...  
Keyword(s):  
Mouse Model ◽  
Cell Lines ◽  
Therapeutic Agent ◽  
Chemotherapeutic Agent ◽  
Experimental System ◽  
Resistant Cell ◽  
Isoquinoline Alkaloid ◽  
Therapeutic Resistance ◽  
In Vivo Efficacy

Abstract Background The ability to treat glioblastoma (GBM) using the chemotherapeutic agent temozolomide (TMZ) has been hampered by the development of therapeutic resistance. In this study, we assessed the ability of the isoquinoline alkaloid berberine to alter GBM TMZ resistance using two different TMZ-resistant cell lines to mimic a physiologically relevant GBM experimental system. Methods By treating these resistant cell lines with berberine followed by TMZ, we were able to assess the chemosensitivity of these cells and their parental strains, based on their performance in the MTT and colony formation assays, as well as on the degree of detectable apoptosis that was detected in the strains. Furthermore, we used Western blotting to assess autophagic responses in these cell lines, and we extended this work into a xenograft mouse model to assess the in vivo efficacy of berberine. Results Through these experiments, our findings indicated that berberine enhanced autophagy and apoptosis in TMZ-resistant cells upon TMZ treatment in a manner that was linked with ERK1/2 signaling. Similarly, when used in vivo, berberine increased GBM sensitivity to TMZ through ERK1/2 signaling pathways. Conclusions These findings demonstrate that berberine is an effective method of increasing the sensitization of GBM cells to TMZ treatment in a manner that is dependent upon the ERK1/2-mediated induction of autophagy, thus making berberine a potentially viable therapeutic agent for GBM treatment.

CHIR258, a Novel Multi-Targeted Tyrosine Kinase Inhibitor, for the Treatment of t(4;14) Multiple Myeloma.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 641-641 ◽  
Author(s):  
Suzanne Trudel ◽  
Zhi Hua Li ◽  
Ellen Wei ◽  
Marion Wiesmann ◽  
Katherine Rendahl ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Mouse Model ◽  
Tyrosine Kinase ◽  
Cell Lines ◽  
Small Molecule ◽  
Kinase Inhibitor ◽  
Wild Type ◽  
Myeloma Cells

Abstract The t(4;14) translocation that occurs uniquely in a subset (15%) of multiple myeloma (MM) patients results in the ectopic expression of the receptor tyrosine kinase, Fibroblast Growth Factor Receptor3 (FGFR3). Wild-type FGFR3 induces proliferative signals in myeloma cells and appears to be weakly transforming in a hematopoeitic mouse model. The subsequent acquisition of FGFR3 activating mutations in some MM is associated with disease progression and is strongly transforming in several experimental models. The clinical impact of t(4;14) translocations has been demonstrated in several retrospective studies each reporting a marked reduction in overall survival. We have previously shown that inhibition of activated FGFR3 causes morphologic differentiation followed by apoptosis of FGFR3 expressing MM cell lines, validating activated FGFR3 as a therapeutic target in t(4;14) MM and encouraging the clinical development of FGFR3 inhibitors for the treatment of these poor-prognosis patients. CHIR258 is a small molecule kinase inhibitor that targets Class III–V RTKs and inhibits FGFR3 with an IC50 of 5 nM in an in vitro kinase assay. Potent anti-tumor and anti-angiogenic activity has been demonstrated in vitro and in vivo. We employed the IL-6 dependent cell line, B9 that has been engineered to express wild-type FGFR3 or active mutants of FGFR3 (Y373C, K650E, G384D and 807C), to screen CHIR258 for activity against FGFR3. CHIR258 differentially inhibited FGF-mediated growth of B9 expressing wild-type and mutant receptors found in MM, with an IC50 of 25 nM and 80 nM respectively as determined by MTT proliferation assay. Growth of these cells could be rescued by IL-6 demonstrating selectivity of CHIR258 for FGFR3. We then confirmed the activity of CHIR258 against FGFR3 expressing myeloma cells. CHIR258 inhibited the viability of FGFR3 expressing KMS11 (Y373C), KMS18 (G384D) and OPM-2 (K650E) cell lines with an IC50 of 100 nM, 250 nM and 80 nM, respectively. Importantly, inhibition with CHIR258 was still observed in the presence of IL-6, a potent growth factors for MM cells. U266 cells, which lack FGFR3 expression, displayed minimal growth inhibition demonstrating that at effective concentrations, CHIR258 exhibits minimal nonspecific cytotoxicity on MM cells. Further characterization of this finding demonstrated that inhibition of cell growth corresponded to G0/G1 cell cycle arrest and dose-dependent inhibition of downstream ERK phosphorylation. In responsive cell lines, CHIR258 induced apoptosis via caspase 3. In vitro combination analysis of CHIR258 and dexamethasone applied simultaneously to KMS11 cells indicated a synergistic interaction. In vivo studies demonstrated that CHIR258 induced tumor regression and inhibited growth of FGFR3 tumors in a plasmacytoma xenograft mouse model. Finally, CHIR258 produced cytotoxic responses in 4/5 primary myeloma samples derived from patients harboring a t(4;14) translocation. These data indicate that the small molecule inhibitor, CHIR258 potently inhibits FGFR3 and has activity against human MM cells setting the stage for a Phase I clinical trial of this compound in t(4;14) myeloma.

NR4A3 Suppresses Lymphomagenesis In Vitro and In Vivo by Induction of Similar Patterns of Pro-Apoptotic Genes like NR4A1

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2728-2728
Author(s):  
Alexander JA Deutsch ◽  
Beate Rinner ◽  
Martin Pichler ◽  
Karoline Fechter ◽  
Hildegard T. Greinix ◽  
...  
Keyword(s):  
Mouse Model ◽  
B Cell ◽  
Cell Lines ◽  
Lymphoma Cell ◽  
Receptor Expression ◽  
Aggressive Lymphoma ◽  
Aggressive Lymphomas ◽  
Apoptotic Genes

Abstract The nuclear orphan receptors NR4A1 and NR4A3 have been demonstrated as cooperating tumour suppressor genes leading to rapid development of acute myeloid leukaemia (AML) in double knock-out mice. In humans, their expression is reduced in leukemic blasts in AML patients. Furthermore, NR4A1 and NR4A3 hypoallelic mice develop preleukemic myelodysplastic/myeloproliferative disorders with progression to AML in some cases. Recently we published a comprehensive study of NR4A nuclear receptor expression levels in lymphoid neoplasms that revealed a marked reduction of NR4A1 and NR4A3 in the majority of patients with B-cell chronic lymphocytic leukaemia, with follicular lymphoma, and with diffuse large B cell lymphoma. Interestingly, functional characterization demonstrated that NR4A1 induces apoptosis of aggressive lymphoma cells in vitro and suppresses tumour growth in a xenograft mouse model. Since the role of NR4A3 in aggressive lymphomas is unknown, we aimed to investigate its etiopathogenic function in these tumors. Low expression of NR4A3 was associated with poor survival in aggressive lymphoma patients. Experimentally, induction of NR4A3 expression by inducible ectopic expression in a variety of lymphoma cell lines led to a significantly higher proportion of apoptotic cells as demonstrated by DNA cleavage, Annexin V staining and increased caspase 3/7 activity. To test the tumor suppressor functions of NR4A3 in vivo, the stably transduced SuDHL4-lymphoma cell line was xenografted in the NOD-SCID-gamma (NSG) mouse model. In this system NR4A3 expression abrogated tumor growth in the NSG mice, whereas vector control and uninduced cells formed massive lymphoid tumors. Pharmacological activation of NR4A3 by Thapsigargin and BF175 resulted in a NR4A3 dependent induction of apoptosis in vitro. To dissect differential transcriptional activity of NR4A3 and NR4A1,both factors were separately over-expressed in four different aggressive lymphoma cell lines followed by semi-quantitative mRNA expression analysis of intrinsic and extrinsic apoptotic genes. NR4A1 or NR4A3 over-expression caused apoptosis by induction of BAK, Puma, BIK, BIM, BID and Trail to the same degree. In summary, our data suggest that NR4A3 possesses tumor suppressive function in aggressive lymphomas by pro-apoptotic transactivation and that NR4A3 is functional redundant to NR4A1 in aggressive lymphomas. Disclosures No relevant conflicts of interest to declare.

scholarly journals The Effects of PI3K-δ/γ Inhibitor, Duvelisib, in Mantle Cell Lymphoma in Vitro and in Patient-Derived Xenograft Studies

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 3016-3016 ◽  
Author(s):  
Jack Wang ◽  
Victoria Zhang ◽  
Taylor Bell ◽  
Yang Liu ◽  
Hui Guo ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Mantle Cell Lymphoma ◽  
Cell Lines ◽  
Cell Lymphoma ◽  
Oral Gavage ◽  
Patient Derived Xenograft ◽  
Pdx Model ◽  
Mantle Cell

Abstract Background: Mantle cell lymphoma (MCL) is an incurable subtype of B-cell lymphoma. Ibrutinib, a first-in-class, once-daily, oral covalent inhibitor of Bruton's tyrosine kinase (BTK) was approved by the FDA for the treatment of MCL in patients previously treated. In our prior multicenter Phase 2 clinical trial, the overall response rate in relapsed/refractory MCL was 68%, with a median progression-free survival (PFS) of 13.9 months. However, the majority of MCL patients treated with ibrutinib relapsed; in these relapsed patients, the one-year survival rate was only 22%. Therefore, there exists an urgent need for additional novel targeted therapies to improve the mortality rate in these patients. In this study, we assessed the in vitro and in vivo effects of duvelisib, a PI3K-δ,-γ inhibitor, in MCL. Methods: The PI3K/AKT/mTOR and other cell survival signaling pathways were investigated by RNASeq and reverse phase protein array (RPPA) in ibrutinib-sensitive and -resistant MCL samples. The expression of PI3K isoforms, α, β, γ, and δ was tested in 11 MCL cell lines, patient and patient-derived xenograft (PDX) MCL cells by western blot analysis. We then investigated the growth inhibition and apoptosis of duvelisib (IPI-145, Infinity Pharmaceuticals, Inc.) in MCL cells by CellTiter-Glo® Luminescent Cell Viability Assay (Promega) and Annexin V-binding assay (BD Biosciences). We established a primary MCL-bearing PDX model and passaged the primary MCL tumor to next generations. Mice were administrated with 50 mg/kg duvelisib daily by oral gavage. Tumor burden and survival time were investigated in the MCL-PDX model. Results: We found that the PI3K/AKT/mTOR signaling pathway was activated in both primary and acquired ibrutinib-resistant MCL cell lines and PDX MCL cells. We immunoblotted PI3K isoforms, α, β, γ, and δ in 11 MCL cell lines and the result demonstrated that both ibrutinib-sensitive and ibrutinib-resistant MCL cells dominantly expressed PI3K-δ and -γ. Next, we tested the effects of duvelisib on these MCL cells. Duvelisib had effects on the growth inhibition and apoptosis in both ibrutinib-sensitive and ibrutinib-resistant MCL cells as good as the PI3K-δ inhibitor, idelalisib (Cal-101, GS-1101). The PI3K-δ isoform could play a very important role in PI3K-mediated signals in MCL. We then investigated the effects of duvelisib in vivo through our established MCL-bearing PDX mouse models. These models are created by inoculating the primary tumor cells from MCL patients into a human fetal bone chip implanted into NSG mice to provide a microenvironment that reconstitutes the human environment. MCL tumor mass was then passaged to next generations for therapeutic investigation of duvelisib. Mice were treated with 50 mg/kg duvelisib daily by oral gavage. Our data demonstrated that duvelisib significantly inhibited tumor growth and prolonged survival of MCL-PDX mice. Conclusion: Duvelisib, an oral dual inhibitor of PI3K-δ,-γ, inhibits MCL growth both in vitro and in PDX mice. These preclinical results suggests duvelisib may be effective in the treatment of patients with relapsed/refractory MCL. Disclosures No relevant conflicts of interest to declare.

Effect of AdipoR agonist in cholangiocarcinoma.

2018 ◽  
Vol 36 (4_suppl) ◽  
pp. 323-323
Author(s):  
Khac Cuong Bui ◽  
Mai Ly Thi Nguyen ◽  
Samarpita Barat ◽  
Xi Chen ◽  
Vikas Bhuria ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Mouse Model ◽  
Cell Lines ◽  
Colony Formation ◽  
Tumor Burden ◽  
Potential Candidate ◽  
Anti Cancer ◽  
Apoptosis Assay

323 Background: Adiponectin is the key adipokine, which plays an important role in health and disease such as obesity, diabetes, and cancer. Adiponectin is reduced in different tumor types, especially in obesity-related cancer, and recent studies showed that Adiponectin had a potential anti-cancer effect. Obesity is a risk factor for various tumor diseases including cholangiocarcinoma (CC), the second most common primary hepatic cancer. The aim of this study is to investigate for the first time the anti-cancer effect of AdipoR agonist in CC cell lines and a CC engineered mouse model. Methods: Human CC cell lines (TFK-1 and SZ-1) and CC engineered mice (Alb-Cre/KRASG12D/p53L/L) were used to investigate the anti-cancer effects of an AdipoR agonist (2-(4-Benzoylphenoxy)-N-[1-(phenylmethyl)-4-piperidinyl]-acetamide). Cell proliferation, migration, invasion, colony formation, apoptosis assay were applied to evaluate the effect of AdipoR agonist in vitro. In addition, important cancer signalling pathways and targets were analysed by Western Blot. Mice (n = 12) were treated with AdipoR or verhicle and tumor burden and survival were monitored. Results: AdipoR agonist suppressed proliferation, migration, invasion, colony formation and apoptosis in CC cells. AdipoR agonist regulated the expression of different proteins such as EMT markers, pAMPK, pSTAT3, and PARP, which have pivotal functions in cholangiocarcinogenesis. AdipoR agonist also prolonged survival time in a CC engineered mouse model. Conclusions: Our data revealed that AdipoR agonist inhibited successfully cell proliferation, migration, invasion, colony formation and apoptosis in vitro, and prolonged mice survival in vivo through regulation of crucial signaling pathways in cholangiocarcinogenesis. These results suggested that AdipoR agonist might become a new potential candidate for CC treatment in the future.

Efficacy of Panobinostat (LBH589) in Multiple Myeloma Cell Lines and In Vivo Mouse Model: Tumor-Specific Cytotoxicity and Protection of Bone Integrity in Multiple Myeloma.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1510-1510 ◽  
Author(s):  
Joseph D. Growney ◽  
Peter Atadja ◽  
Wenlin Shao ◽  
Youzhen Wang ◽  
Minying Pu ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Death ◽  
Bone Density ◽  
Mouse Model ◽  
Cortical Bone ◽  
Cell Lines ◽  
Single Agent ◽  
Synergistic Cytotoxicity

Abstract Panobinostat (LBH589) is a highly potent oral pan-deacetylase (DAC) inhibitor currently undergoing clinical development in hematologic and solid malignancies. Here we report the effects of panobinostat on multiple myeloma (MM) cells in vitro and in a murine xenograft model in vivo. Panobinostat exhibited potent cytotoxic activity (IC50 &lt;10 nM) against 8 MM cell lines (KMS-12PE, KMS-18, LP-1, NCI H929, KMS-11, RPMI8226, OPM-2, and U266). Panobinostat has been shown to affect signals involved in MM cell-cycle arrest and cell death, and to induce apoptosis via mitochondrial perturbation. In addition, panobinostat has been shown to selectively induce cell death of plasma cells isolated from MM patients without toxicity to normal lymphocytes or granulocytes. To investigate the effect of panobinostat in vivo, a disseminated luciferized MM.1S xenograft mouse model was treated with vehicle or panobinostat 15 mg/kg by intraperitoneal (i.p.) administration qd×5 for 3 weeks. Panobinostat treatment reduced the burden of MM.1S tumor cells to 22% treated over control (T/C) relative to vehicle-treated animals. In addition, MM.1S tumor-bearing mice treated with panobinostat displayed reduced trabecular and cortical bone damage relative to vehicle-treated animals. The mean ± SEM trabecular bone density and cortical bone density (% Bone Volume/Total Volume) of panobinostat-treated animals was 14.5% ± 2.0 and 98.1% ± 0.4, respectively, compared with 2.2% ± 0.3 and 89.1% ± 1.5 in vehicle-treated animals. In combination with the proteosome inhibitor bortezomib (BZ), panobinostat displayed significant synergistic cytotoxicity without additional toxicity to normal bone marrow stromal cells in vitro. In the MM.1S-luciferase tumor mouse model, combined treatment with panobinostat at 10 mg/kg i.p. qd×5 for 4 weeks and BZ at 0.2 mg/kg intravenously 1qw for 4 weeks reduced tumor burden to 7% T/C relative to vehicle, panobinostat alone (31% T/C), or BZ alone (44% T/C). Disease progression, measured as median time to endpoint (TTE) was improved from 37 to 54 days (P&lt;0.05) by panobinostat and to 46 days by BZ (P&lt;0.05). The combination treatment further improved clinical outcome relative to both single-agent treatment groups (P&lt;0.05), extending the TTE to 73 days. In contrast to BZ, the immunomodulatory drug thalidomide (TH) had no significant single-agent activity at 150 mg/kg p.o. qd for 4 weeks. However, combination activity (18% T/C) was observed when TH was combined with a sub-efficacious dose of panobinostat (5 mg/kg, 64% T/C). Combination of panobinostat and TH increased the TTE to 50 days, compared with 37.5, 43, and 39.5 days (P&lt;0.05), respectively, for the vehicle, panobinostat, or TH as single agents. These data demonstrate that panobinostat exhibits significant anti-proliferative and anti-tumor activities on MM cells both in vitro and in vivo. Panobinostat, as a single agent or in combination with BZ or TH, is a promising therapy for MM, and these studies may provide the rationale for clinical evaluation of panobinostat and BZ combination in the treatment of MM.

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