scholarly journals 47 Preclinical studies of dianhydrogalactitol (VAL-083) in DIPG, as single agent or as a combination with AZD1775 or radiation

2018 ◽  
Vol 45 (S3) ◽  
pp. S9-S10
Author(s):  
Xiaodong Yang ◽  
Anne Steino ◽  
Jeffrey Bacha ◽  
Dennis Brown ◽  
Sabine Mueller
Keyword(s):  
Cell Cycle ◽  
Cell Lines ◽  
Dna Methyltransferase ◽  
Cell Cycle Progression ◽  
Single Agent ◽  
Chemotherapeutic Agents ◽  
Phase Cell ◽  
Dna Double Strand Breaks

Despite decades of trials, the prognosis for diffuse intrinsic pontine gliomas (DIPG) remains dismal. DIPG is inoperable and standard treatment is radiation alone, as the addition of chemotherapeutic agents, such as temozolomide, have not improved survival. In addition to inherent chemoresistance, treatment of DIPG is impeded by an intact blood-brain barrier (BBB). VAL-083 is a structurally unique bi-functional DNA-targeting agent that readily crosses the BBB. VAL-083 forms interstrand DNA crosslinks at N7-guanine, resulting in DNA double-strand breaks (DSB), S/G2-phase cell-cycle arrest, and ultimately cancer cell death. We have previously demonstrated that VAL-083 is able to overcome temozolomide-resistance in vitro and in vivo, and that its cytotoxicity is independent of the DNA-repair enzyme O6-methylguanine DNA-methyltransferase (MGMT). MGMT is almost universally expressed in DIPG and its expression is strongly correlated with temozolomide-resistance. VAL-083’s distinct mechanism-of-action suggests the potential for combination with inhibitors of DNA DSB repair or S/G2 cell-cycle progression (e.g. Wee1 inhibitor AZD1775). Here, we investigated the effects of VAL-083 in combination with radiation, AZD1775 or irinotecan (topoisomerase inhibitor) in three DIPG cell-lines: SF10693 (H3.1), SF8628 (H3.3) and NEM157 (H3.3). VAL-083 showed activity at low uM-concentration in all three cell-lines. In addition, VAL-083 showed synergy with AZD1775 in all three cell-lines. Combined with its ability to cross the BBB, accumulate in brain tumor tissue and overcome MGMT-related chemoresistance, these results suggest VAL-083 as a potentially attractive treatment option for DIPG as single agent or in combination with AZD1775. Combination studies with radiation are ongoing and will be presented at the meeting.

scholarly journals Anticancer Activity of Cynomorium coccineum

Cancers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 354 ◽  
Author(s):  
Mouna Sdiri ◽  
Xiangmin Li ◽  
William Du ◽  
Safia El-Bok ◽  
Yi-Zhen Xie ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Death ◽  
Anticancer Activity ◽  
Cancer Cells ◽  
Cell Lines ◽  
Cancer Cell ◽  
Cell Cycle Progression ◽  
Cycle Progression

The extensive applications of Cynomorium species and their rich bioactive secondary metabolites have inspired many pharmacological investigations. Previous research has been conducted to examine the biological activities and numerous interesting pharmaceutical activities have been reported. However, the antitumor activities of these species are unclear. To understand the potential anticancer activity, we screened Cynomorium coccineum and Cynomorium songaricum using three different extracts of each species. In this study, the selected extracts were evaluated for their ability to decrease survival rates of five different cancer cell lines. We compared the cytotoxicity of the three different extracts to the anticancer drug vinblastine and one of the most well-known medicinal mushrooms Amaurederma rude. We found that the water and alcohol extracts of C. coccineum at the very low concentrations possessed very high capacity in decreasing the cancer cells viability with a potential inhibition of tumorigenesis. Based on these primitive data, we subsequently tested the ethanol and the water extracts of C. coccineum, respectively in in vitro and in vivo assays. Cell cycle progression and induction of programmed cell death were investigated at both biological and molecular levels to understand the mechanism of the antitumor inhibitory action of the C. coccineum. The in vitro experiments showed that the treated cancer cells formed fewer and smaller colonies than the untreated cells. Cell cycle progression was inhibited, and the ethanol extract of C. coccineum at a low concentration induced accumulation of cells in the G1 phase. We also found that the C. coccineum’s extracts suppressed viability of two murine cancer cell lines. In the in vivo experiments, we injected mice with murine cancer cell line B16, followed by peritoneal injection of the water extract. The treatment prolonged mouse survival significantly. The tumors grew at a slower rate than the control. Down-regulation of c-myc expression appeared to be associated with these effects. Further investigation showed that treatment with C. coccineum induced the overexpression of the tumor suppressor Foxo3 and other molecules involved in inducing autophagy. These results showed that the C. coccineum extract exerts its antiproliferative activity through the induction of cell death pathway. Thus, the Cynomorium plants appear to be a promising source of new antineoplastic compounds.

scholarly journals (S)-10-Hydroxycamptothecin Inhibits Esophageal Squamous Cell Carcinoma Growth In Vitro and In Vivo Via Decreasing Topoisomerase I Enzyme Activity

Cancers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1964 ◽  
Author(s):  
Mengqiu Song ◽  
Shuying Yin ◽  
Ran Zhao ◽  
Kangdong Liu ◽  
Joydeb Kumar Kundu ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Enzymatic Activity ◽  
Topoisomerase I ◽  
Cell Cycle Progression ◽  
Caspase 3 ◽  
Cyclin B1 ◽  
Phase Cell ◽  
Cycle Progression

Topoisomerase (TOP) I plays a major role in the process of supercoiled DNA relaxation, thereby facilitating DNA replication and cell cycle progression. The expression and enzymatic activity of TOP I is positively correlated with tumor progression. Although the anticancer activity of (S)-10-Hydroxycamptothecin (HCPT), a TOP I specific inhibitor, has been reported in various cancers, the effect of HCPT on esophageal cancer is yet to be examined. In this study, we investigate the potential of HCPT to inhibit the growth of ESCC cells in vitro and verify its anti-tumor activity in vivo by using a patient-derived xenograft (PDX) tumor model in mice. Our study revealed the overexpression of TOP I in ESCC cells and treatment with HCPT inhibited TOP I enzymatic activity at 24 h and decreased expression at 48 h and 72 h. HCPT also induced DNA damage by increasing the expression of H2A.XS139. HCPT significantly decreased the proliferation and anchorage-independent growth of ESCC cells (KYSE410, KYSE510, KYSE30, and KYSE450). Mechanistically, HCPT inhibited the G2/M phase cell cycle transition, decreased the expression of cyclin B1, and elevated p21 expression. In addition, HCPT stimulated ESCC cells apoptosis, which was associated with elevated expression of cleaved PARP, cleaved caspase-3, cleaved caspase-7, Bax, Bim, and inhibition of Bcl-2 expression. HCPT dramatically suppressed PDX tumor growth and decreased the expression of Ki-67 and TOP I and increased the level of cleaved caspase-3 and H2A.XS139 expression. Taken together, our data suggested that HCPT inhibited ESCC growth, arrested cell cycle progression, and induced apoptosis both in vitro and in vivo via decreasing the expression and activity of TOP I enzyme.

In Vitro and in Vivo Single-Agent Efficacy of Checkpoint Kinase 1 (Chk1) and 2 (Chk2) Inhibitor PF-0477736 (Pfizer) in B- and T-Acute Lymphoblastic Leukemia (ALL)

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1496-1496 ◽  
Author(s):  
Ilaria Iacobucci ◽  
Andrea Ghelli Luserna Di Rorà ◽  
Maria Vittoria Verga Falzacappa ◽  
Enrico Derenzini ◽  
Anna Ferrari ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Dna Damage ◽  
Western Blot ◽  
Cell Lines ◽  
Single Agent ◽  
Time Dependent ◽  
Leukemia Cells ◽  
In Vivo Models

Abstract Abstract 1496 Introduction: Although progress in the treatment of ALL has been remarkable in children, in adults ALL still carries a dismal outcome. Thus, there is a need to improve therapeutic options. In the last years, selective inhibitors of Chk1 and/or Chk2 have been discovered, developed and entered in clinical trials. However, so far, they have not yet been investigated in leukemia. Chk1 and Chk2 are serine/threonine kinases that play a critical role in response to DNA damage both by halting the cell cycle through checkpoint activation and by actively repairing DNA. Here, we explored the in vitro and in vivo activity of single-agent inhibition of Chk1/2 by PF-0477736 in B- and T-progenitor ALL and we investigated potential biomarkers of functional inhibition. Methods: Human B (BCR-ABL1-positive: BV-173, SUPB-15; BCR-ABL1- negative: NALM-6, NALM-19, REH) and T (MOLT-4, RPMI-8402, CEM) leukemia cell lines were incubated with increasing concentrations of drug (5–2000 nM) for 24, 48 and 72 hours (hrs). Results: Inhibition of Chk1/2 resulted in a dose and time-dependent cytotoxicity with RPMI-8402 and BV-173 cells being the most sensitive (IC50 at 24 hrs: 57 nM and 82 nM, respectively), while NALM-6 cells the most resistant (IC50 at 24 hrs: 1426 nM)(WST-1 assay, Roche). Sensitivity did not correlate with p53 status (BV-173, SUPB-15, NALM-6 and NALM-19 cells were p53 wild-type whereas REH, MOLT-4, RPMI-8402 and CEM cells were p53 mutated) and with baseline levels of Chk1/2 and ATR/ATM phosphorylation, indicative of intrinsic genetic stress. Consistent with the viability results, Annexin V/Propidium Iodide (PI) staining analysis showed a significant increase of apoptosis at 24 and 48 hrs in a dose and time dependent manner coupled to increased proteolytic cleavage of PARP-1. In all sensitive cell lines in addition to the induction of apoptosis, Chk1/Chk2 inhibition induced DNA damage as demonstrated by the increased number of γH2AX foci (western blot and immunofluorescence analysis) and by a marked phosphorylation of Chk1 (ser317 and ser345). Moreover, PF-0477736 efficiently triggered the Chk1-Cdc25-Cdk1 pathway as soon as 24 hrs of treatment with a decrease of the inhibitory phosphorylation of Cdc25c (ser216) and Cdk1 (tyr15), leading to the abrogation of cell cycle arrest as confirmed by PI staining analysis at 6 and 24 hrs. The efficacy of PF-0477736 was thereafter demonstrated in primary leukemic blasts separated from 14 ALL patients. Based on the viability results at 24 hrs, 3 groups of patients were identified: very good responders, 5/14, 36% (IC50: 100–500 nM); good responders, 6/14, 43% (IC50: 600–1000 nM); poor responders, 3/14, 21% (IC50 > 1000 nM). By contrast, PF-0477736 did not show efficacy in primary cultures of normal bone marrow mononuclear cells, demonstrating its specificity for leukemia cells. We extended the in vitro and ex-vivo studies by assessing the efficacy of Chk inhibition in mice transplanted with T-lymphoid leukemia, demonstrating that PF-0477736 increases the survival of treated mice compared with mice treated with vehicle (p = 0.0016). Finally, in order to elucidate the mechanisms of action of PF-0477736 and to determine biomarkers of response, gene expression profiling analysis (Affymetrix GeneChip Human Gene 1.0 ST) was performed on treated leukemia cells and their untreated counterparts (DMSO 0.1%) after 24 hrs of incubation with concentrations equal to the IC50. Treatment resulted in a differential expression (p < 0.05) of genes involved in chromatin assembly, nucleosome organization and DNA packaging (e.g. Histone H1-H2A, 2B family clusters), DNA damage (DDIT3, GADD34 and GADD45a) and apoptosis (e.g. CDKN1A, BAX, FAS, BTG1), confirming that PF-0477736 contributes to checkpoint replication abrogation, accumulation of DNA damage and subsequent apoptosis in leukemia cells. Interestingly, N-Myc and c-Myc expression strongly decreased after treatment, as also confirmed by western blot analysis, suggesting that a negative feedback loop may exist between Chk induction and Myc expression. Conclusions: Together, these results demonstrate the efficacy of PF-0477736 both in vitro and in vivo models of ALL, arguing in favor of its future clinical evaluation in leukemia. Supported by ELN, AIL, AIRC, Fondazione Del Monte di Bologna-Ravenna, PRIN2009, PIO program, Programma Ricerca Regione-Università 2007–2009. PF-0477736 provided by Pfizer. Disclosures: Baccarani: ARIAD, Novartis, Bristol Myers-Squibb, and Pfizer: Consultancy, Honoraria, Speakers Bureau. Martinelli:NOVARTIS: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; PFIZER: Consultancy; ARIAD: Consultancy.

scholarly journals Novel Combination Therapy Targeting rDNA Transcription and Histone Deacetylation Provides Effective Treatment for Multiple Myeloma, and Synergises in Bortezomib-Resistant MM

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1945-1945
Author(s):  
Kylee H Maclachlan ◽  
Andrew Cuddihy ◽  
Nadine Hein ◽  
Carleen Cullinane ◽  
Simon J. Harrison ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Multiple Myeloma ◽  
Drug Resistance ◽  
Cell Lines ◽  
Cellular Response ◽  
Single Agent ◽  
Resistant Cell ◽  
Rdna Transcription

Abstract Background: Multiple myeloma (MM) requires combination drug therapies to delay acquired drug resistance and clinical relapse. We co-developed CX-5461, a highly-selective inhibitor of RNA polymerase I-mediated rDNA transcription(1), currently in phase I trials for relapsed haematological malignancies (Peter Mac). CX-5461 produces a targeted nucleolar DNA damage response (DDR), triggering both a p53-dependent and -independent nucleolar stress response and killing malignant cells while sparing normal cells(2,3). Single-agent CX-5461 provides an impressive survival benefit in mouse models of B-cell lymphoma, acute myeloid leukaemia and now MM(2,4,5). However, drug resistance eventually occurs, confirming the need for combination therapies. Aim: To test the efficacy of CX-5461 in combination with the histone deacetylase inhibitor panobinostat, (prioritised from a boutique high-throughput screen of anti-myeloma agents), with a focus on the setting of resistance to proteasome-inhibitors (PIs). Methods: We assessed the impact of CX-5461 and panobinostat on overall survival in mouse models of MM, then surveyed the effects on cellular response and molecular markers of DDR. We developed bortezomib-resistant cell lines and an in vivo model of bortezomib-resistance to test this combination in the setting of PI-resistance. Results: CX-5461 in combination with panobinostat provides a significant survival advantage in both the transplanted Vk*MYC and the 5T33/KaLwRij models, with minimal bone marrow toxicity. The combination showed increased anti-proliferative effects and cell death in vitro. Interestingly, experiments interrogating the downstream cellular response of this combination suggest that the mechanism(s) driving synergy are complex and cell context-dependent. Cell cycle analysis indicates that both CX-5461- and panobinostat-driven cell cycle effects, i.e. G2/M and G1/S arrest, respectively, are dominant in the combination setting in a cell line-dependent manner, suggesting that context-dependent factors such as p53 may influence the cellular response. Mechanistically, in both p53-wild type and -null cell lines we observe an increase in DDR signalling with single agent CX-5461, with only moderate further increase with the combination. Moreover, CX-5461-mediated MYC downregulation is not universally observed, with the combination promoting further downregulation only in some cell lines. Given the potential for affecting global transcription programs downstream of panobinostat, we are performing transcriptome analyses in the combination setting compared to single agent treatment. We have generated bortezomib-resistant cell lines, sequentially increasing drug exposure to establish populations growing at concentrations above the IC90 of the parental lines. The resistant 5T33 cells retain their resistance to bortezomib in vivo and we have demonstrated that CX-5461 remains effective in this model, significantly increasing survival. We are currently examining the combination of CX-5461 with panobinostat in this model of bortezomib-resistance, which will give critical information guiding patient selection for future clinical trials. Conclusion: The rDNA transcription inhibitor CX-5461 synergises in vitro and in vivo with panobinostat, and CX-5461 retains efficacy in the setting of bortezomib-resistant myeloma. References Drygin et al., Cancer Research 2011 Bywater et al., Cancer Cell 2012 Quin et al, Oncotarget, 2016 Devlin et al., Cancer Discovery 2016 Hein et al., Blood 2017 Disclosures Harrison: Janssen-Cilag: Other: Scientific advisory board.

scholarly journals Evaluation of Terpenes Psiadin, Plectranthone, and Saudinolide as Selective Anti-Cancer Agents against Hepatic Carcinoma Cells

2020 ◽  
Author(s):  
Khaled Y. Orabi ◽  
Mohamed S. Abaza ◽  
Rajaa Al-Attiyah ◽  
Yunus A. Luqmani
Keyword(s):  
Cell Cycle ◽  
Cell Lines ◽  
Cancer Cell ◽  
Cell Cycle Progression ◽  
Molecular Mechanisms ◽  
Therapeutic Potential ◽  
Cancer Cell Lines ◽  
Chemotherapeutic Agents ◽  
Isolation And Purification

: Plant-derived terpenes have aroused considerable interest as chemotherapeutic agents for a variety of diseases. This study aimed at the isolation and purification of the scarce terpenes psiadin, plectranthone and saudinolide from their respective plants, followed by the determination of antiproliferative activity, against hepatic cancer cell lines (HepG2, Hep3B), and the potential molecular mechanisms. Time- and dose-dependent cytotoxicity, evaluated using MTT and colony-forming assays, were exhibited by psiadin and plectranthone against the cancer cells. Flow cytometry showed that these two terpenes blocked cell cycle progression and induced mitochondrial-mediated apoptosis, particularly through increased cytochrome c and disruption of mitochondrial membrane potential. Additionally, they initiated the generation of reactive oxygen species as well as inhibiting NF-B. Psiadin lowered several essential cyclins and cyclin-dependent kinases and reduced RB activation. It was concluded that psiadin, in particular, has a significant therapeutic potential with the biggest advantage of differentiating between cancer and normal cells which is acutely lacking in current cytotoxic drugs. Its precise mode of action needs further investigation but appears predominantly to cause cell cycle arrest by interfering with cyclin production. It will be important to determine, in future studies, whether these terpenes will similarly inhibit other cancer cell lines and retain its activity against tumors in vivo.

scholarly journals Pirtobrutinib Overcomes Ibrutinib and Venetoclax Resistance in Mantle Cell Lymphoma

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 1182-1182
Author(s):  
Yang Liu ◽  
Changying Jiang ◽  
Fangfang Yan ◽  
Joseph McIntosh ◽  
Alexa A Jordan ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Lines ◽  
Research Funding ◽  
Cell Cycle Progression ◽  
Cell Lymphoma ◽  
Xenograft Model ◽  
Mantle Cell ◽  
Btk Inhibitor

Abstract Background Mantle cell lymphoma (MCL) is a rare and aggressive B-cell lymphoma characterized by poor prognosis. Although remarkable therapeutic advances have been made by covalent Bruton's tyrosine kinase (BTK) inhibition and CAR T cell therapy, therapeutic resistance inevitably occurs and leads to dismal clinical outcome. Pirtobrutinib (LOXO-305) is a next-generation, highly selective and non-covalent BTK inhibitor. A phase 1/2 BRUIN study showed that pirtobrutinib demonstrated promising efficacy in heavily pretreated MCL patients with or without prior covalent BTK inhibition. Here, we investigated the mechanism of action of pirtobrutinib in MCL cells in vitro and proposed the potential combination therapy in a venetoclax-resistant xenograft model. Methods MCL cell proliferation was monitored by trypan blue exclusion assay after 24-, 48- and 72-hour treatment with pirtobrutinib and ibrutinib. We performed Annexin V/PI staining to measure the apoptosis inductive effects. Cell cycle analysis using propidium iodide (PI) DNA staining was conducted to compare cell cycle progression kinetics between pirtobrutinib and ibrutinib. We performed RNAseq analysis in Z138 cells to compare differentially expressed genes (DEGs) between pirtobrutinib and ibrutinib treatment. Western blotting was utilized to detect specific signaling proteins. Mino-venetoclax-R cells were inoculated subcutaneously into NSG mice and used for in vivo drug efficacy determination. Results Compared to covalent BTK inhibitor ibrutinib, the novel non-covalent BTK inhibitor pirtobrutinib was more potent in inhibiting MCL cell proliferation in a panel of MCL cell lines, especially in ibrutinib/venetoclax resistant cell lines (pirtobrutinib vs. ibrutinib, p&lt;0.01). Treatment with pirtobrutinib (10μM) for 24 hours induced higher levels of apoptosis than that by ibrutinib in all the MCL cell lines tested (p&lt;0.05), which was also confirmed at the molecular level by stronger caspase-3 activation and PARP cleavage. To understand the mechanism of action, we performed whole transcriptomic profiling by RNAseq analysis using Z138 cells treated with/without pirtobrutinib or ibrutinib. Pirtobrutinib treatment resulted in upregulation of 137 genes and downregulation of 97 genes compared to the ibrutinib treatment (adjusted p&lt;0.05). In addition to the downregulated MYC targets and PI3K/Akt pathway, gene set enrichment analysis (GSEA) revealed a significant enrichment for G2/M checkpoints and E2F targets signatures (key genes: PLK1, CDKN1A and CCNB1) in pirtobrutinib treated cells. Consistently, follow-up studies showed that γH2AX level was highly increased upon pirtobrutinib treatment. Pirtobrutinib treatment but not ibrutinib treatment resulted in G2/M cell cycle arrest. The blockade of cell cycle progression is positively correlated with decreased protein levels of critical regulators of S and G2/M phase transition such as cyclin B and CDC25C. BTK inhibitor (ibrutinib) in combination with venetoclax has shown great efficacy in preclinical models and in MCL patients. Therefore, here we assessed the in vivo efficacy of pirtobrutinib in combination with venetoclax with side-by-side comparison to ibrutinib & venetoclax in the Mino-venetoclax-R mouse model. Pirtobrutinib & venetoclax combination enhanced the efficacy of pirtobrutinib in restraining the tumor size (p&lt;0.001) in the xenograft model. Notably, this novel combinatorial treatment exerted much higher potency than ibrutinib and venetoclax combination therapy (p&lt;0.001). In addition, the pirtobrutinib & venetoclax combination was well tolerated and did not reduce overall mouse body weights compared with the vehicle treated mice. Conclusions Pirtobrutinib overcame both ibrutinib and venetoclax resistance in MCL cells in vitro and in vivo. G2/M checkpoints and E2F targets pathways were significantly enriched in both cases. Pirtobrutinib & venetoclax showed better in vivo efficacy in MCL models than combination of ibrutinib & venetoclax. Figure 1 Figure 1. Disclosures Wang: Genentech: Consultancy; Juno: Consultancy, Research Funding; Kite Pharma: Consultancy, Honoraria, Research Funding; Clinical Care Options: Honoraria; CAHON: Honoraria; InnoCare: Consultancy, Research Funding; Moffit Cancer Center: Honoraria; Molecular Templates: Research Funding; Oncternal: Consultancy, Research Funding; DTRM Biopharma (Cayman) Limited: Consultancy; Hebei Cancer Prevention Federation: Honoraria; Lilly: Research Funding; Loxo Oncology: Consultancy, Research Funding; BioInvent: Research Funding; OMI: Honoraria; Miltenyi Biomedicine GmbH: Consultancy, Honoraria; Imedex: Honoraria; Physicians Education Resources (PER): Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Bayer Healthcare: Consultancy; Chinese Medical Association: Honoraria; Dava Oncology: Honoraria; Celgene: Research Funding; Mumbai Hematology Group: Honoraria; Acerta Pharma: Consultancy, Honoraria, Research Funding; BeiGene: Consultancy, Honoraria, Research Funding; Newbridge Pharmaceuticals: Honoraria; CStone: Consultancy; BGICS: Honoraria; The First Afflicted Hospital of Zhejiang University: Honoraria; Scripps: Honoraria; Epizyme: Consultancy, Honoraria; Pharmacyclics: Consultancy, Research Funding; AstraZeneca: Consultancy, Honoraria, Research Funding; VelosBio: Consultancy, Research Funding; Anticancer Association: Honoraria.

DTCM-glutarimide Delays Growth and Radiosensitizes Glioblastoma

2019 ◽  
Vol 18 (9) ◽  
pp. 1323-1329 ◽  
Author(s):  
Gabriela Molinari Roberto ◽  
Helder Henrique Paiva ◽  
Lucas Eduardo Botelho de Souza ◽  
Julia Alejandra Pezuk ◽  
Gabriela Maciel Vieira ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Lines ◽  
Cell Cycle Progression ◽  
Combined Treatment ◽  
Clonogenic Survival ◽  
Antitumor Effects ◽  
Induce Cell Cycle Arrest ◽  
Invasion Capacity

Background and Purpose: Glioblastoma (GBM) is the most aggressive brain tumor. Even with the advent of temozolomide, patient survival remains poor, with expected median survival around 1 year from diagnosis. Consequently, the relentless search for new therapeutic strategies able to increase patient outcome persists. 3-[(dodecylthiocarbonyl) methyl] glutarimide (DTCM-g) is a new anti-inflammatory compound that already showed antitumor effects. Materials and Methods: Clonogenic survival, proliferation, apoptosis, cell cycle progression and invasion capacity of pediatric and adult GBM cell lines (U87MG, U251MG, SF188 and KNS-42) were evaluated under treatment with DTCM-g. The combined treatment with radiation was also evaluated in vitro and in vivo through xerographic models. Results: DTCM-g is able to impair proliferation, reduce clonogenic capacity and induce cell cycle arrest in GBM cell lines. No alteration in apoptosis rates was found after treatment. DTCM-g also reduces the invasion capacity of all GBM cell lines without alterations in MMP2 and uPa expression. Moreover, the drug radiosensitized GBM in vitro and in vivo. Conclusion: Although additional studies are still necessary to support our findings, our results suggest that DTCM-g may be a promising drug on the adjuvant treatment of GBM exhibiting antitumor effects, especially through radiosensitization.

Phosphatidylinositol-3 Kinase Delta (PI3Kδ) Inhibitor AMG 319 Is a Potent, Selective and Orally Bioavailable Small Molecule Inhibitor That Suppresses PI3K-Mediated Signaling and Viability in Neoplastic B Cells

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4964-4964 ◽  
Author(s):  
Angus Sinclair ◽  
Daniela Metz ◽  
Tim Cushing ◽  
Liqin Liu ◽  
Rachael Brake ◽  
...  
Keyword(s):  
B Cell ◽  
Cell Lines ◽  
Small Molecule ◽  
Single Agent ◽  
Chemotherapeutic Agents ◽  
B Cell Malignancies ◽  
Molecule Inhibitor ◽  
Human B Cell

Abstract Abstract 4964 Immune receptors such as the B cell receptor (BCR) require key signaling intermediate phosphatidylinositol-3 kinase delta (PI3Kδ) for normal immune cell survival, development and function. PI3Kδ is a class IA lipid kinase, is expressed primarily within the hematopoietic system and is composed of a catalytic subunit p110δ and a regulatory subunit p85. Recently, deregulated BCR-PI3Kδ signaling has been reported to play a role in B-cell malignancies such as chronic lymphocytic leukemia (CLL) and non-Hodgkin's lymphoma (NHL) by mediating abnormal B-cell growth and survival. Indeed, the constitutive phosphorylation of downstream signaling intermediate AKT is associated with poor prognosis in several B cell malignancies. Here, we have investigated the potential of a novel small molecule inhibitor of PI3Kδ, AMG 319, to suppress PI3K signaling in human B cell lines and assessed the subsequent effects on viability as a single agent and in combination with chemotherapeutic drugs in preclinical models. Small molecule AMG 319 is a potent and selective inhibitor of PI3Kδ with excellent preclinical pharmacokinetic (PK) properties. AMG 319 was found to potently inhibit PI3Kδ in enzyme assays (IC50 <10 nM). AMG 319 also potently suppressed the phosphorylation of AKT (pAKTS473) in primary murine splenocytes (IC50<5 nM) after BCR cross linking and demonstrated a less than 10 fold shift in human whole blood B cells using a similar BCR pAKT assay in vitro. In a cell based selectivity screen, AMG 319 was selective for PI3Kδ against other PI3K class I isoforms (200 to >5000 fold). Furthermore, AMG 319 was considered inactive at 10 μM on non-PI3K class I kinases in a broader kinome screen of 402 kinases. In preclinical PK studies, AMG 319 had low systemic clearance, T1/2 range of 2–4 hr, oral bioavailability of >45% and unbound fractions in plasma of 5–19%. Here, we have investigated the potential for AMG 319 to inhibit constitutive PI3K mediated signaling and effects on human B cell line viability. In a broad screen of >20 cell lines derived from B cell malignancies, the majority of lines were found to express PI3Kδ protein, all cells lines expressed the PI3Kα and β isoforms and variable levels of constitutive pAKTS473 were detected. AMG 319 was found to potently suppress constitutive pAKTS473 in the cell lines with IC50 in the low single to double digit nM range. Cellular viability was inhibited by AMG 319 though lines were variably sensitive to drug (range low double digit nM to μM IC50). As cell lines were variably sensitive to AMG 319 as a single agent, we examined if AMG 319 could enhance the efficacy of chemotherapeutic agents in vitro and in vivo. These studies focused on a DLBCL cell line HT which was relatively insensitive to AMG 319 as a single agent (IC50 ∼10 μM) in viability assays even though pAKTS473 was potently suppressed (IC50 ∼ 0.030 μM). Treatment with AMG 319 was found to synergize with the effects of vincristine to reduce cell viability in vitro using a 72 hr viability assay. Next we examined whether the enhanced cytotoxicity using these drugs in combination could be observed in vivo. Using the human B-cell lymphoma HT xenograft model, we found that AMG 319 in combination with vincristine enhanced tumor growth inhibition above that observed with either agent alone. Taken together, these findings suggest that the inhibition of PI3Kδ with AMG 319 may enhance the effects of chemotherapeutic agents in B cell malignancies. In conclusion, AMG 319 is a potent and selective inhibitor of PI3Kδ with excellent PK properties. AMG 319 inhibited constitutive pAKTS473, reduced the viability of B cell lines and synergized with vincristine in vitro and in vivo. The safety, PK and preliminary efficacy of AMG 319 are currently being investigated in a Phase I trial in patients with relapsed or refractory lymphoid malignancies. Disclosures: Sinclair: Amgen: Employment, Stock and Options. Metz:Amgen, Inc: Employment, Stock and Options. Cushing:Amgen, Inc: Employment, Stock and Options. Liu:Amgen, Inc: Employment, Stock and Options. Brake:Amgen, Inc: Employment, Stock and Options. Starnes:Amgen, Inc: Employment, Stock and Options. Means:Amgen, Inc: Employment, Stock and Options. Henne:Amgen, Inc: Employment, Stock and Options. Archibeque:Amgen: Employment, Stock and Options. Mattson:Amgen, Inc: Employment, Stock and Options. Drew:Amgen, Inc: Employment, Stock and Options. Busse:Amgen, Inc: Employment, Stock and Options. Wang:Amgen, Inc: Employment, Stock and Options. Al-Assaad:Amgen, Inc: Employment, Stock and Options. Molineux:Amgen: Employment, Stock and Options.

Weighted Gene Co-Expression Network Analysis (WGCNA) Identifies Highly Proliferative Myeloma Subgroup Responsive to CDK4/ARK5 Inhibition

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3445-3445 ◽  
Author(s):  
Deepak Perumal ◽  
Violetta V. Leshchenko ◽  
Pei-Yu Kuo ◽  
Zewei Jiang ◽  
Ben Readhead ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Lines ◽  
Cell Cycle Progression ◽  
Advisory Board ◽  
Drug Induced ◽  
Scientific Advisory Board ◽  
Scientific Advisory ◽  
Equity Ownership

Abstract Multiple myeloma (MM) is an incurable plasma cell malignancy accounting for more than 10,000 deaths in the US each year. Hence the pursuit for novel therapeutic agents remains critically important. Myeloma pathogenesis is associated in part with aberrant cell cycle progression. Inhibition of cyclin dependent kinases CDK4/6 results in cell cycle arrest and sensitization to Bortezomib and other active agents in MM (Huang, Blood 2012). Here, we show that ARK5, a novel member of the human AMPKfamily, is overexpressed in 70% of MM and helps promote proliferation and cell cycle progression via G1/S phase activation in an mTOR dependent manner. We examined the role of ARK5 using loss of function studies by ARK5 siRNA transfection in MM1.S, NCI-H929 cells as well as treatment with ON 123300, a dual CDK4/ARK5 kinase inhibitor. ARK5 siRNA knockdown decreased MM cell viability and cell proliferation via G1/S arrest compared to control siRNA. ARK5 siRNA treatment significantly (~70%) induced apoptosis in MM cells as detected by Annexin V/PI staining. We observed that phosphorylation of Rb, a critical cell cycle protein was significantly reduced in ARK5 depleted cells. Moreover, mTOR pathway inhibition was confirmed by reduction of pS6K in ARK5depleted cells as compared to control siRNA treated cells. ON 123300 decreased viability in MM cell lines and patient cells but was not lethal to normal PBMCs. A single treatment of 50nM drug stratified MM cell lines into 2 groups, 5 resistant (MM.1R, KMS11, U266, RPMI-8226 and ARP1) and 4 sensitive cell lines (>80% cell kill-MM.1S, EJM, JJN3, NCI-H929). ARK5 protein expression by western blot analysis was much higher in sensitive cell lines. ON 123300 triggered G0/G1 cell cycle arrest and induced apoptosis similar to the effect of ARK5 siRNA (80% vs 70%). ON 123300 treatment also reduced phosphorylation of pRb and pS6K downstream of mTOR pathway. These results confirm that cell inhibitory effects of ON 123300 in MM are mediated in a large part via inhibition of ARK5. Co-culture experiments with BMSCs showed that ON 123300 not only targets MM cells but also overcomes the cytoprotective effects of the MM-host BM microenvironment. 4/5 ARK5 positive primary samples with adverse cytogenetics including 1q amplification and CyclinD1 translocation were sensitive to ON 123300 (>80% cytotoxicity) at 50nM. Further, IP injection of ON 123300 (100mg/kg) in tumor xenograft models (MM1.S, NCI-H929) showed that ON 123300 is well tolerated and significantly inhibits tumor growth in vivo(p<0.001). To study the mechanism of action for ON 123300, we performed geneset enrichment analysis (GSEA) on drug induced gene expression signature of RNA-Seq data from pre-post treated cell lines. We interrogated a wide array of geneset libraries, including MSigDB (Subramanian, PNAS 2005), drug induced transcriptional modules (Iskar, Mol Sys Bio. 2013) and disease signatures (Sirota, Sci Transl Med 2011). GSEA showed significant representation of genes that are enriched in normal plasma cells and rapamycin sensitive geneset. Next, we developed a weighted co-expression network (WGCNA, Langfelder BMC Bioinformatics 2008) based classifier using 304 MM samples from MMRC collection and RNA-Seq from 28 MM patients from Mt. Sinai Hospital. WGCNA defines a network that continuously links all genes and then clusters the most highly co-expressed genes in defined modules. These network modules were associated with clinical traits and UAMS GEP classification (Zhan, Blood 2006) of each sample. There was significant overlap between highly proliferative “PR” and “Cyclin D1/2” patient subsets based on classification and sensitivity to CDK4/ARK5 inhibition. Our classifier accurately discriminated 4 sensitive primary samples from one resistant sample, all tested in vitro. All sensitive samples were either Cyclin D1/2 or PR as per UAMS classification. Our preclinical studies provide the basis for clinical evaluation of CDK4/ARK5 inhibitor ON 123300 due to its selective cytotoxicity on MM cells in vitro and in vivo. Using WGCNA we establish a systematic framework by constructing for the first time, MM-associated gene co-expression networks contributing to tumorigenesis and progression. Thus, WGCNA modeling is a novel approach for identification of MM patient subgroups that have a higher likelihood of response in clinical trials with CDK4/ARK5 inhibitors. Disclosures Chari: Array BioPharma: Scientific Advisory Board Other; Celgene Corporation: Scientific Advisory Board, Scientific Advisory Board Other; Millennium Pharmaceuticals, Inc: Scientific Advisory Board, Scientific Advisory Board Other; Onyx Pharmaceuticals, Inc.: Scientific Advisory Board, Scientific Advisory Board Other. Reddy:Onconova Therapeutics, Inc.: Consultancy, Patents & Royalties. Reddy:Onconova Therapeutics, Inc.: Consultancy, Patents & Royalties. Dudley:Ecoeos, Inc: Consultancy, Equity Ownership; GNS Healthcare: Consultancy; GlaxoSmithKline: Consultancy; Ayasdi, Inc: Equity Ownership; NuMedii, Inc: Equity Ownership; Ubalo, Inc.: Equity Ownership. Jagannath:Onyx Pharmaceuticals, Inc.: Consultancy; Celgene Corporation: Scientific Advisory Board, Scientific Advisory Board Other; Millennium Pharmaceuticals, Inc. : Scientific Advisory Board, Scientific Advisory Board Other.

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