scholarly journals Targeting CDK9 and MCL-1 by a new CDK9/p-TEFb inhibitor with and without 5-fluorouracil in esophageal adenocarcinoma

2019 ◽  
Vol 11 ◽  
pp. 175883591986485 ◽  
Author(s):  
Zhimin Tong ◽  
Alicia Mejia ◽  
Omkara Veeranki ◽  
Anuj Verma ◽  
Arlene M. Correa ◽  
...  

Background: CDK9 inhibitors are antitumorigenic against solid tumors, including esophageal adenocarcinoma (EAC). However, efficacy of a CDK9 inhibitor combined with 5-fluorouracil (5-FU) and target proteins that are targeted by these agents in EAC are unknown. Methods: The anti-EAC efficacy of a new CDK9 inhibitor, BAY1143572, with and without 5-FU was assessed in vitro and in xenograft models in athymic nu/nu mice. Synergy between BAY1143572 and 5-FU in inhibiting cell proliferation was analyzed by calculating the combination index using CompuSyn software. Potential targets of BAY1143572 and 5-FU were identified by reverse-phase protein array. The effects of BAY1143572 and 5-FU on MCL-1 in vitro were analyzed by Western blotting, quantitative real-time polymerase chain reaction, and chromatin immunoprecipitation assay. MCL-1 protein expression in tumors from patients with locoregional EAC treated with chemoradiation and surgery was assessed by immunohistochemistry. Results: BAY1143572 had dose-dependent antiproliferative and proapoptotic effects and demonstrated synergy with 5-FU against EAC in vitro. The median volumes of FLO-1 and ESO-26 xenografts treated with 5-FU plus BAY114352 were significantly smaller than those of xenografts treated with either agent alone ( p < 0.05). BAY1143572 downregulated MCL-1 by inhibiting HIF-1α binding to the MCL-1 promoter. 5-FU enhanced BAY1143572-induced MCL-1 downregulation and stable MCL-1 overexpression reduced the apoptosis induced by BAY1143572 and 5-FU in vitro. High patients’ tumor MCL-1 expression was correlated with shorter overall and recurrence-free survival. Conclusions: BAY1143572 and 5-FU have synergistic antitumorigenic effects against EAC. MCL-1 is a downstream target of CDK9 inhibitors and a predictor of response to neoadjuvant chemoradiation in EAC.

Zygote ◽  
2013 ◽  
Vol 23 (1) ◽  
pp. 58-67 ◽  
Author(s):  
Olympia Pikiou ◽  
Anna Vasilaki ◽  
George Leondaritis ◽  
Nikos Vamvakopoulos ◽  
Ioannis E. Messinis

SummaryStudies on bovine oocytes have revealed that the activation of adenosine monophosphate activated protein kinase (AMPK) by millimolar concentrations of metformin controls nuclear maturation. Tuberous sclerosis complex 2 (TSC2) has been identified as a downstream target of AMPK. The objective of this study was to investigate the effects of addition of low concentrations of metformin (1 nM to 10 μM) on the percentage of cultured cumulus–oocyte complexes (COC) giving rise to cleavage-stage embryos and AMPK-mediated TSC2 activation. Metformin was supplemented either throughout in vitro embryo production (IVP) or only during in vitro fertilization (IVF). COC were matured in vitro, inseminated, and presumptive zygotes cultured for a further 72 h post insemination before the percentage of COC that gave rise to zygotes and early embryo development was assessed. The presence of TSC2 in bovine embryos and its possible AMPK-induced activation were assessed by immunocytochemistry. Metformin had a dose-dependent effect on the numbers of cultured COC that gave rise to embryos. Drug treatment either throughout IVP or only during IVF decreased the percentage of ≥8-cell embryos (1 μM, P < 0.05; 10 μM, P < 0.01; and 0.1 μM, 10 μM, P < 0.01, respectively) and increased the percentage of 2-cell embryos (10 μM, P < 0.01 and P < 0.05 respectively). The percentage of cultured COC that gave rise to zygotes was not affected by metformin. TSC2 is expressed in early embryos. Metformin (10 μM) either throughout IVP or during IVF only, increased AMPK-induced PhosphoS1387-TSC2 immunoreactivity (P < 0.01) and this increase corresponded to the total TSC2 protein levels expressed in cells. Our results suggest that there is a dose-dependent negative effect of metformin on the ability of oocytes to cleave following insemination, possibly mediated through an AMPK-induced activation of TSC2.


2021 ◽  
Author(s):  
Hao Wang ◽  
Wei Wei ◽  
Zhong-Yuan Zhang ◽  
Yao Liu ◽  
Bin Shi ◽  
...  

Abstract Background: Metastasis remains the major obstacle to improved survival for colorectal cancer (CRC) patients. Dysregulation of N6-methyladenosine (m6A) is causally associated with the development of metastasis through poorly understood mechanisms. Methods: The expression of METTL14 and its correlation with clinicopathological features were evaluated by western blot and immunohistochemistry. The roles of METTL14 in CRC metastasis were determined through in vitro and in vivo assays. The underlying mechanisms of METTL14 regulation were explored using transcriptome-sequencing, m6A-seguencing, methylated RNA immunoprecipitation (MeRIP), m6A dot blot, RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assay.Results: METTL14 is functionally related to the inhibition of ARRDC4/ZEB1 signaling and to the consequent suppression of CRC metastasis. We unveil METTL14-mediated m6A modification profile and identify ARRDC4 as a direct downstream target of METTL14. Knockdown of METTL14 significantly enhances ARRDC4 mRNA stability relying on the “reader” protein YHTDF2 dependent manner. Moreover, TCF4 can induce METTL14 protein expression, and HuR suppresses METTL14 expression by directly binding to its promoter. Clinically, decreased METTL14 is correlated with poor prognosis and acts as an independent predictor of CRC survival. Conclusion: Our data suggest that TCF4 and HuR mediated-METTL14 can trigger the metastasis of CRC during cancer development via YHTDF2/ARRDC4/ZEB1 axis, which imposes great challenge that inhibition of METTL14 is a potential approach for cancer treatment.


2020 ◽  
Author(s):  
Xiaohui Shen ◽  
Han Gao ◽  
Yuchen Zhang ◽  
Zhuoqing Xu ◽  
Wenqing Feng ◽  
...  

Abstract Background: Oxaliplatin resistance is a major challenge for treatment of metastatic colorectal cancer (mCRC). Many molecular targeted drugs for refractory CRC have been developed to solve colorectal cancer drug resistance, but their effectiveness and roles in the progression of CRC and oxaliplatin- resistance still not clear.Methods: PDOs derived from CRC patients were constructed to conduct the sensitivity assays of oxaliplatin in vitro. Oxaliplatin resistant PDOs were selected and treated under the combined treatment of ML264(a KLF5 inhibitor) and oxaliplatin to determine the effects of KLF5 inhibition on apoptosis. Using CRC cell lines to investigate downstream mechanisms and xenograft models to confirm whether ML264 can restore oxaliplatin sensitivity of CRC cells in vivo.Results: We successfully constructed CRC PDOs and conducted the sensitivity test of oxaliplatin in PDOs from different patients. We found that ML264 restores oxaliplatin sensitivity in CRC PDOs by restoring the apoptotic response, and this effect was achieved by inhibiting the KLF5/Bcl-2/caspase3 signal pathway. Chromatin immunoprecipitation (ChIP) and luciferase reporter assay verified that KLF5 promoted the transcription of Bcl-2 in CRC cells. KLF5 inhibition also overcomed oxaliplatin resistance in xenograft tumors.Conclusions: Our study demonstrated that ML264 can restores oxaliplatin sensitivity in CRC PDOs by restoring the apoptotic response. KLF5 might be a potential therapeutic target for CRC resistant to oxaliplatin. PDOs have strong potential in evaluating inhibitors and drug combinations therapy in a preclinical environment.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1107-1107 ◽  
Author(s):  
Alex R. Shoemaker ◽  
Michael J. Mitten ◽  
Jessica Adickes ◽  
Anatol Oleksijew ◽  
Haichao Zhang ◽  
...  

Abstract ABT-263 is an orally bioavailable small molecule inhibitor of Bcl-2 family proteins with a Ki of ≤ 1 nM against Bcl-2, Bcl-XL, and Bcl-w. Potent cytotoxic effects have been demonstrated against small cell lung carcinomas and lymphomas (EC50 of less than 500 nM in vitro against numerous cell lines). Tumor growth stasis and regression in xenograft models confirmed this activity. However, a unique thrombocytopenia has been observed in mice, rats, and dogs. Using a mouse model to characterize the extent and duration of decreased circulating platelets, outbred CF-1 or inbred scid-bg mice were treated with increasing doses of ABT-263. Blood samples were collected at various times post dosing and platelet numbers were determined using automated hematology analysis. The results showed a rapid, dose-dependent reduction in circulating platelet counts with a platelet nadir (>80% reduction relative to baseline) occurring approximately 6 hours after a single 100 mg/kg oral dose of ABT-263. Platelet counts returned to normal levels by 72 hrs post-dose. Analysis of bleeding times using a tail-nick method demonstrated a correlation between reduced platelet count and increased bleeding time. At doses of 50 mg/kg and higher, bleed times were increased by more than 5-fold relative to vehicle controls. In multi-dose studies, platelet levels did not continue to decline relative to the first dose of ABT-263. Mice treated with ABT-263 at 100 mg/kg/day for as long as 21 days exhibited no overt signs of toxicity (bleeding, significant weight loss, etc). Because the spleen is a potential site for clearing of damaged or aggregated platelets, a study using splenectomized mice was also conducted. The kinetics of platelet reduction and recovery were similar in splenectomized vs. intact mice with no additional adverse events noted. Evaluations of plasma drug levels associated with preclinical anti-tumor efficacy vs. thrombocytopenic effects indicate that a reasonable therapeutic window exists for ABT-263.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3919-3919
Author(s):  
Alfons Navarro ◽  
Tania Díaz ◽  
Antonio Martinez ◽  
Anna Gaya ◽  
Mariano Monzó

Abstract Abstract 3919 Background: The constitutive activation of the JAK/STAT pathway plays an important role in the pathogenesis and proliferation of Hodgkin Lymphoma (HL). Although somatic activating point mutations in the JAK2 gene have been reported in myeloproliferative disorders (MPD), they are rarely described in HL, where JAK2 amplification is associated with mutations of regulator genes such as SOCS-1, constitutive activation of STAT proteins or miRNA deregulation. Recently, many JAK2 inhibitors, including Lestaurtinib (CEP701), have been reported to have clinical efficacy in MPD. CEP701 is a multitargeted tyrosine kinase inhibitor that potently inhibits FLT3 at nanomolar concentrations. Recent studies in MPD have further shown that CEP701 inhibitory activity is not limited to FLT3 and can suppress JAK2/STAT5 signaling through JAK2 inhibition. As a first step towards elucidating the potential role of CEP701 in HL therapy, we have analyzed its efficacy in vitro. Methods: Four HL cell lines, L-428, L-1236, HDMYZ and L-540, were assayed for proliferation, apoptosis and levels of proteins in the JAK2/STAT pathway (pJAK2, JAK2, pSTAT5, STAT5, Bcl-xL) after CEP701 treatment. 100,000 cells were plated in a 96-well plate in 100 ml culture medium with CEP701 or DMSO (vehicle control) at concentrations of 30–300 nM. After 1 or 24 hours of incubation with CEP701, the levels of the proteins and of FLT3 were analyzed by Western blot. Proliferation was analyzed with CellTiter 96 AQueous One Solution Cell Proliferation Assay (MTS) and apoptosis by CaspaseGlo 3/7 after 48 hours of treatment. Results: The proliferation analysis showed an effective dose-dependent inhibition of cell growth in the 4 HL cell lines after treatment with increasing concentrations of CEP701. At 48h, in comparison to cells treated with DMSO alone (normalized to 100%), in cells treated with 100nM of CEP701, we observed a marked inhibition of 35% in L-428, 55% in L-1236, 15% in HDMYZ and 77% in L-540. Moreover, apoptosis increased by 38%, 31%, 21% and 25%, respectively. The protein analysis showed that after one hour, CEP701 inhibited phosphorylation of JAK2 (pJAK2) and its downstream target STAT5 (pSTAT5) in a dose-dependent manner, with no changes in the non-phosphorylated proteins. The downstream target Bcl-xL also decreased. Conclusions: Taken together, these data demonstrate that growth inhibition and apoptosis activation by CEP701 in HL cells correlates with the inhibition of the JAK2/STAT5-dependent signal transduction pathway. Here we present the first biological evidence that Lestaurtinib could be a promising new agent in the treatment of patients with HL. Supported by a FIS grant (PS09/00547). Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4888-4888
Author(s):  
Li Long ◽  
Xia Tong ◽  
Montesa Patawaran ◽  
Lea Aukerman ◽  
Bahija Jallal ◽  
...  

Abstract CD40 is expressed on most B cell malignancies including multiple myeloma and represents an attractive target for antibody therapy. We have generated a novel, highly potent, fully human antagonistic anti-CD40 monoclonal antibody, CHIR-12.12, using XenoMouse® mice (Abgenix, Inc). The antibody can mediate anti-tumor activity potentially by at least two mechanisms: CHIR-12.12 can block CD40-ligand mediated survival signals and it can lyse tumor cells by antibody-dependent cellular cytotoxicity (ADCC). We have previously reported that CHIR-12.12 mediates stronger killing of CD40- and CD20-expressing lymphoma cells than rituximab by ADCC in vitro and significantly inhibits the growth of both rituximab-responsive and rituximab-resistant human lymphoma xenografts in vivo. In this study, we examined in vitro and in vivo efficacy of CHIR-12.12 against human multiple myeloma. The human MM cell line IM-9, which expresses both CD40 and CD20, the target antigen for CHIR-12.12 and rituximab respectively was used for the study. CHIR-12.12 induced lysis of target tumor cells by ADCC in a dose dependent manner reaching maximum cell lysis at 0.1ug/ml concentration. The maximum specific lysis of IM-9 cells by CHIR-12.12 was greater than the lysis induced by rituximab (64% vs 45 %, n=3, p<0.01). In addition, the EC50 of CHIR-12.12 was on average 5.9 picomolar, which was 10-fold lower than the EC50 of rituximab. Greater ADCC by CHIR-12.12 was not due to higher density of CD40 molecules on the target tumor cells compared to CD20 molecules. IM-9 cells expressed 35590 ±8858 CD40 molecules compared to 93783 ± 2247 CD20 molecules. The in vivo CHIR-12.12 efficacy was then evaluated in IM-9 xenograft model. In an un-staged conditional survival model, where treatment began one day after intravenous inoculation of IM-9 tumor cells, CHIR-12.12 significantly prolonged the survival of tumor-bearing mice in a dose-dependent manner with 60% survival in the 0.1 mg/kg CHIR-12.12 treated group and 80% survival in the 1 and 10 mg/kg groups respectively on day 56 (Log Rank Test: P<0.01 and P<0.001, respectively). All animals in the control IgG1 and bortezomib treated groups were terminated between day 18 and day 26 due to severe disease related to tumor development (i.e., hind limb paralysis and significant body weight loss). In a staged subcutaneous model, where treatment began once the tumor volume was 150–200mm3, CHIR-12.12 administered weekly at 0.1, 1 and 10 mg/kg significantly inhibited tumor growth with a tumor volume reduction of 17% (P>0.05), 34% (P<0.01) and 44% (P<0.001) respectively. Bortezomib, when tested at 0.5 mg/kg twice a week did not inhibit tumor growth. At the maximally tolerated dose (MTD) of 1 mg/kg twice a week, bortezomib inhibited tumor growth by 30% (P<0.01). Taken together, these data demonstrate that the anti-CD40 mAb CHIR-12.12 has potent activity against human multiple myeloma in vitro and xenograft models in vivo.


Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3470-3470 ◽  
Author(s):  
Li Long ◽  
Xia Tong ◽  
Montesa Patawaran ◽  
Sharon L. Aukerman ◽  
Bahija Jallal ◽  
...  

Abstract CD40 is expressed on all B-cell malignancies, including multiple myeloma, and represents an attractive target for antibody therapy. CHIR-12.12 is a fully human, highly potent, IgG1 antagonistic anti-CD40 monoclonal antibody generated using XenoMouse® mice (Abgenix, Inc). CHIR-12.12 can mediate antitumor activity by at least two mechanisms: blocking CD40-ligand-mediated survival signals and killing tumor cells by antibody-dependent cellular cytotoxicity (ADCC). We have previously reported that CHIR-12.12 mediates stronger in vitro killing of CD40+- and CD20+-expressing human non-Hodgkin’s lymphoma and lymphoblastoid B cells by ADCC than rituximab and significantly inhibits the growth of rituximab-responsive (Daudi) and rituximab-resistant (Namalwa) human lymphoma and lymphoblastoid B-cell (IM-9) xenografts in vivo. In this study, we examined the in vitro and in vivo efficacy of CHIR-12.12 against the human multiple myeloma cell line KMS-12-BM. CHIR-12.12 induced lysis of KMS-12-BM cells by ADCC in a dose-dependent manner, reaching maximum cell lysis at 0.1μg/ml with an EC50 of 17.5 pM. CHIR-12.12 efficacy in vivo was evaluated in orthotopic and subcutaneous KMS-12-BM xenograft models. In the staged orthotopic model, tumor cells were delivered intravenously and treatment was initiated 7 days post cell implantation. CHIR-12.12 significantly prolonged the median survival of tumor-bearing mice in a dose-dependent manner, with a median survival of 78 and 98 days in the groups treated with 1 mg/kg and 10 mg/kg CHIR-12.12 weekly, respectively, compared to a median survival time of 68 days in the control IgG1 group (P<0.0001). Bortezomib administered i.v. twice weekly at 0.5 or 1 mg/kg showed no survival benefit. In the staged subcutaneous model, CHIR-12.12 was administered weekly at 1 and 10 mg/kg after the mean tumor volume reached 100mm3. CHIR-12.12 significantly inhibited tumor growth, with a tumor volume reduction of 42% (P<0.05) and 63% (P<0.01), respectively. Bortezomib and melphalan/prednisone did not inhibit KMS-12-BM tumor growth at the doses and schedules reported for other human multiple myeloma xenograft models. Western blot analysis and immunohistochemical staining showed significantly increased levels of cleaved PARP in KMS-12-BM s.c. tumors 7 days after the initiation of CHIR-12.12 treatment, suggesting the induction of cell death by CHIR-12.12. Taken together, these data demonstrate that the anti-CD40 mAb CHIR-12.12 has potent activity against human multiple myeloma cells in vitro and in xenograft models in vivo. Currently CHIR-12.12 is in Phase I clinical trials for the treatment of B-cell malignancies.


2004 ◽  
Vol 24 (7) ◽  
pp. 2757-2766 ◽  
Author(s):  
Isabel Rodrigo ◽  
Paola Bovolenta ◽  
Baljinder S. Mankoo ◽  
Kenji Imai

ABSTRACT The axial skeleton of vertebrates derives from the sclerotomal compartment of the somites. Genetic analysis has demonstrated that the transcription factors Pax1, Pax9, Meox1, Meox2, and Bapx1 are all required for sclerotomal differentiation. Their hierarchical relationship is, however, poorly understood. Because Bapx1 expression in the somites starts slightly later than that of the Meox genes, we asked whether Bapx1 is one of their downstream targets. Our analysis of Meox1; Meox2 mutant mice supports this hypothesis, as Bapx1 expression in the sclerotome is lost in the absence of both Meox proteins. Using transient-transfection assays, we show that Meox1 activates the Bapx1 promoter in a dose-dependent manner and that this activity is enhanced in the presence of Pax1 and/or Pax9. Furthermore, by electrophoretic mobility shift and chromatin immunoprecipitation experiments, we demonstrate that Meox1 can bind the Bapx1 promoter. The palindromic sequence TAATTA, present in the Bapx1 promoter, binds the Meox1 protein in vitro and is necessary for Meox1-induced transactivation of the Bapx1 promoter. Our data demonstrate that the Meox genes are required for Bapx1 expression in the sclerotome and suggest that the mechanism by which the Meox proteins exert this function is through direct activation of the Bapx1 gene.


2021 ◽  
Vol 14 ((Supl. 1)) ◽  
pp. 1-13
Author(s):  
Diogo Luan de Oliveira ◽  
Juliana Cristina Schmidt

In this study were identified Candida species from vaginal secretion isolates, evaluated their in vitro antifungal susceptibilities, and correlated these features with antifungal agents prescribed for patients assisted in a primary care service. Species identification by Polymerase Chain Reaction showed that 36.5% of isolates were characterized as non-C. albicans species. In antifungal susceptibility tests most isolates were susceptible to ketoconazole, fluconazole, and itraconazole, although between 40% and 50% of isolates show resistance or dose-dependent susceptibility to miconazole and nystatin, respectively. Analysis of drugs prescribed to patients revealed that 34.2% of the isolates were considered resistant to agents used in treatment. Several Candida species can cause vulvovaginitis and exhibit different susceptibility profiles to antifungal drugs used in treatment. The identification of Candida species is relevant and useful to the epidemiological management of infections. The antifungal susceptibility test may also be useful for choosing most effective drug treatment for each patient.


Pharmacology ◽  
2018 ◽  
Vol 101 (5-6) ◽  
pp. 225-235 ◽  
Author(s):  
Dong Wang ◽  
Jiang Song ◽  
Huasong Ma

Background: 25-hydroxyvitamin D3 (25[OH]VD3) has recently been found to be an active hormone. Its biological actions are also demonstrated in various cell types. However, the precise influences of vitamin D3 (VD3) and its metabolites (25[OH]VD3, 1α,25-dihydroxyvitamin D3 [1α,25-(OH)2VD3]) on the osteoblast differentiation remain largely unknown. In this work, we investigated the effects of VD3 and its metabolites in different concentrations on the early and later osteoblast differentiation and biomineralization. Methods: We first used quantitative real-time polymerase chain reaction (RT-qPCR) to evaluate the responsiveness of osteoblasts to VD3, 25(OH)VD3 or 1α,25-(OH)2VD3. We also evaluated the proliferation, differentiation and biomineralization of osteoblast at different time points via cell counting kit-8 assay and the analysis of osteogenic markers. Results: The experimental results confirmed that osteoblasts could be responsive to 25(OH)VD3 and 1α,25-(OH)2VD3 but could not directly metabolize VD3 and 25(OH)VD3. Only 200 nmol/L VD3 significantly promoted osteoblast proliferation, while 25(OH)VD3 and 1α,25-(OH)2VD3 did not show obvious actions. Moreover, the early osteogenic markers were increased by 25(OH)VD3 and 1α,25-(OH)2VD3 in a dose-dependent manner. More importantly, only 25(OH)VD3 had accelerated the gene and protein expressions of osteocalcin and the biomineralization level of osteoblasts. Conclusions: Our findings provide reliable evidence that 25(OH)VD3 at 100–200 nmol/L can induce the early and later osteoblast differentiation and biomineralization for clinical bone tissue engineering.


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