scholarly journals A Smo/Gli Multitarget Hedgehog Pathway Inhibitor Impairs Tumor Growth

Cancers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1518 ◽  
Author(s):  
Lospinoso Severini ◽  
Quaglio ◽  
Basili ◽  
Ghirga ◽  
Bufalieri ◽  
...  

: Pharmacological Hedgehog (Hh) pathway inhibition has emerged as a valuable anticancer strategy. A number of small molecules able to block the pathway at the upstream receptor Smoothened (Smo) or the downstream effector glioma-associated oncogene 1 (Gli1) has been designed and developed. In a recent study, we exploited the high versatility of the natural isoflavone scaffold for targeting the Hh signaling pathway at multiple levels showing that the simultaneous targeting of Smo and Gli1 provided synergistic Hh pathway inhibition stronger than single administration. This approach seems to effectively overcome the drug resistance, particularly at the level of Smo. Here, we combined the pharmacophores targeting Smo and Gli1 into a single and individual isoflavone, compound 22, which inhibits the Hh pathway at both upstream and downstream level. We demonstrate that this multitarget agent suppresses medulloblastoma growth in vitro and in vivo through antagonism of Smo and Gli1, which is a novel mechanism of action in Hh inhibition.

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 275-275
Author(s):  
Rolf Schwarzer ◽  
Julia Godau ◽  
Hermann Einsele ◽  
Franziska Jundt

Abstract Tumor cell proliferation and survival of Hodgkin/Reed-Sternberg (HRS) cells are triggered through Jagged1 ligand-induced Notch1 signaling via homotypic and heterotypic cell-cell interactions in classical Hodgkin lymphoma. The developmental pathway Notch partly mediates its effects in HRS cells by stimulation of alternative NF-kB signaling. We further demonstrated that high-level expression of the essential Notch coactivator Mastermind-like 2 and downregulation of the Notch inhibitor Deltex1 contribute to aberrant activation of Notch signaling in HRS cells. Our data suggested that targeting the Notch pathway is a rational treatment strategy in classical Hodgkin lymphoma. In this study we analyzed Notch inhibition by use of the gamma secretase inhibitor GSI XII in a Hodgkin lymphoma xenotransplantation model. To this end the HRS cell line L540cy (1 x 107 cells/per mouse) was transplanted into NOD/SCID mice. After tumor growth (0.3 cm³ mean tumor volume) mice were treated daily with increasing doses of GSI XII (5-10 mg/kg). Surprisingly, L540cy cells were completely drug-resistant in vivo in contrast to high GSI XII sensitivity in vitro. To dissect potential mechanisms of drug resistance we performed human StellARrayTM quantitative polymerase chain reaction (qPCR) arrays to analyze Notch target genes in GSI XII-treated compared to untreated L540cy cells. Interestingly, inhibition of Notch activity resulted in strong mRNA upregulation of the transcription factor glioma-associated oncogene 1 (Gli1), a final effector of the developmental signaling pathway Hedgehog (HH). Chromatin immunoprecipitation (ChIP) further revealed that both negative regulatory Notch target proteins Hey1 and Hes7 directly bind three different N-boxes present in the GLI1 first intron to suppress GLI1 mRNA expression in untreated L540cy cells. In general, the HH pathway is activated through ligand binding of secreted Sonic Hedgehog (SHH). As a result Gli transcription factors translocate to the nucleus and induce target gene expression such as GLI1 or CCND1. Despite high secretion of SHH by HRS cells after two days in culture (conditioned medium), HH signaling was inactive in untreated L540cy cells. Only after release of the negative regulatory Notch targets of the hairy and enhancer of split (HES) family through Notch inhibition and concomitant increase of Gli1 expression, HH signaling was activated by SHH. HH signaling mediated drug resistance of L540cy cells in conditioned medium compared to fresh medium (SHH negative) and thereby compensated for reduced Notch activity in vitro. We hypothesized that this mechanism might contribute to GSI XII drug resistance in vivo. To proof our hypothesis we coinhibited the Notch and HH pathways in L540cy cells. As expected inhibition of the HH pathway alone by use of cyclopamine did not significantly reduce growth of L540cy cells. However, simultaneous targeting of L540cy tumors through GSI XII and cyclopamine efficiently controlled tumor cell growth. Our data indicate a first molecular link between Notch and HH in HRS cells mediating drug resistance. We suggest inhibition of both developmental pathways for effective HRS tumor growth control. Disclosures No relevant conflicts of interest to declare.


2019 ◽  
Vol 26 (30) ◽  
pp. 5609-5624
Author(s):  
Dijana Saftić ◽  
Željka Ban ◽  
Josipa Matić ◽  
Lidija-Marija Tumirv ◽  
Ivo Piantanida

: Among the most intensively studied classes of small molecules (molecular weight < 650) in biomedical research are small molecules that non-covalently bind to DNA/RNA, and another intensively studied class is nucleobase derivatives. Both classes have been intensively elaborated in many books and reviews. However, conjugates consisting of DNA/RNA binder covalently linked to nucleobase are much less studied and have not been reviewed in the last two decades. Therefore, this review summarized reports on the design of classical DNA/RNA binder – nucleobase conjugates, as well as data about their interactions with various DNA or RNA targets, and even in some cases protein targets are involved. According to these data, the most important structural aspects of selective or even specific recognition between small molecule and target are proposed, and where possible related biochemical and biomedical aspects were discussed. The general conclusion is that this, rather new class of molecules showed an amazing set of recognition tools for numerous DNA or RNA targets in the last two decades, as well as few intriguing in vitro and in vivo selectivities. Several lead research lines show promising advancements toward either novel, highly selective markers or bioactive, potentially druggable molecules.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jing Liu ◽  
Ying Xie ◽  
Jing Guo ◽  
Xin Li ◽  
Jingjing Wang ◽  
...  

AbstractDevelopment of chemoresistance is the main reason for failure of clinical management of multiple myeloma (MM), but the genetic and epigenetic aberrations that interact to confer such chemoresistance remains unknown. In the present study, we find that high steroid receptor coactivator-3 (SRC-3) expression is correlated with relapse/refractory and poor outcomes in MM patients treated with bortezomib (BTZ)-based regimens. Furthermore, in immortalized cell lines, high SRC-3 enhances resistance to proteasome inhibitor (PI)-induced apoptosis. Overexpressed histone methyltransferase NSD2 in patients bearing a t(4;14) translocation or in BTZ-resistant MM cells coordinates elevated SRC-3 by enhancing its liquid–liquid phase separation to supranormally modify histone H3 lysine 36 dimethylation (H3K36me2) modifications on promoters of anti-apoptotic genes. Targeting SRC-3 or interference of its interactions with NSD2 using a newly developed inhibitor, SI-2, sensitizes BTZ treatment and overcomes drug resistance both in vitro and in vivo. Taken together, our findings elucidate a previously unrecognized orchestration of SRC-3 and NSD2 in acquired drug resistance of MM and suggest that SI-2 may be efficacious for overcoming drug resistance in MM patients.


Oncogenesis ◽  
2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Xin Huang ◽  
Yichao Hou ◽  
Xiaoling Weng ◽  
Wenjing Pang ◽  
Lidan Hou ◽  
...  

AbstractExploring novel anticancer drugs to optimize the efficacy may provide a benefit for the treatment of colorectal cancer (CRC). Disulfiram (DSF), as an antialcoholism drug, is metabolized into diethyldithiocarbamate-copper complex (CuET) in vivo, which has been reported to exert the anticancer effects on various tumors in preclinical studies. However, little is known about whether CuET plays an anti-cancer role in CRC. In this study, we found that CuET had a marked effect on suppressing CRC progression both in vitro and in vivo by reducing glucose metabolism. Mechanistically, using RNA-seq analysis, we identified ALDH1A3 as a target gene of CuET, which promoted cell viability and the capacity of clonal formation and inhibited apoptosis in CRC cells. MicroRNA (miR)-16-5p and 15b-5p were shown to synergistically regulate ALDH1A3, which was negatively correlated with both of them and inversely correlated with the survival of CRC patients. Notably, using co-immunoprecipitation followed with mass spectrometry assays, we identified PKM2 as a direct downstream effector of ALDH1A3 that stabilized PKM2 by reducing ubiquitination. Taken together, we disclose that CuET treatment plays an active role in inhibiting CRC progression via miR-16-5p and 15b-5p/ALDH1A3/PKM2 axis–mediated aerobic glycolysis pathway.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Moein Dehbashi ◽  
Zohreh Hojati ◽  
Majid Motovali-bashi ◽  
Mazdak Ganjalikhani-Hakemi ◽  
Akihiro Shimosaka ◽  
...  

AbstractCancer recurrence presents a huge challenge in cancer patient management. Immune escape is a key mechanism of cancer progression and metastatic dissemination. CD25 is expressed in regulatory T (Treg) cells including tumor-infiltrating Treg cells (TI-Tregs). These cells specially activate and reinforce immune escape mechanism of cancers. The suppression of CD25/IL-2 interaction would be useful against Treg cells activation and ultimately immune escape of cancer. Here, software, web servers and databases were used, at which in silico designed small interfering RNAs (siRNAs), de novo designed peptides and virtual screened small molecules against CD25 were introduced for the prospect of eliminating cancer immune escape and obtaining successful treatment. We obtained siRNAs with low off-target effects. Further, small molecules based on the binding homology search in ligand and receptor similarity were introduced. Finally, the critical amino acids on CD25 were targeted by a de novo designed peptide with disulfide bond. Hence we introduced computational-based antagonists to lay a foundation for further in vitro and in vivo studies.


Blood ◽  
2020 ◽  
Vol 136 (2) ◽  
pp. 210-223 ◽  
Author(s):  
Eun Ji Gang ◽  
Hye Na Kim ◽  
Yao-Te Hsieh ◽  
Yongsheng Ruan ◽  
Heather A. Ogana ◽  
...  

Abstract Resistance to multimodal chemotherapy continues to limit the prognosis of acute lymphoblastic leukemia (ALL). This occurs in part through a process called adhesion-mediated drug resistance, which depends on ALL cell adhesion to the stroma through adhesion molecules, including integrins. Integrin α6 has been implicated in minimal residual disease in ALL and in the migration of ALL cells to the central nervous system. However, it has not been evaluated in the context of chemotherapeutic resistance. Here, we show that the anti-human α6-blocking Ab P5G10 induces apoptosis in primary ALL cells in vitro and sensitizes primary ALL cells to chemotherapy or tyrosine kinase inhibition in vitro and in vivo. We further analyzed the underlying mechanism of α6-associated apoptosis using a conditional knockout model of α6 in murine BCR-ABL1+ B-cell ALL cells and showed that α6-deficient ALL cells underwent apoptosis. In vivo deletion of α6 in combination with tyrosine kinase inhibitor (TKI) treatment was more effective in eradicating ALL than treatment with a TKI (nilotinib) alone. Proteomic analysis revealed that α6 deletion in murine ALL was associated with changes in Src signaling, including the upregulation of phosphorylated Lyn (pTyr507) and Fyn (pTyr530). Thus, our data support α6 as a novel therapeutic target for ALL.


Blood ◽  
1996 ◽  
Vol 87 (7) ◽  
pp. 2723-2731 ◽  
Author(s):  
P Schwarzenberger ◽  
S Spence ◽  
N Lohrey ◽  
T Kmiecik ◽  
DL Longo ◽  
...  

To develop a rapid preclinical in vivo model to study gene transfer into human hematopoietic progenitor cells, MO-7e cells (CD-34+, c-kit+) were infected with multidrug resistance (MDR1)-containing retroviruses and then transplanted into nonobese diabetic severe combined immunodeficient mice (NOD SCID). MO-7e cells infected with a retrovirus encoding the human MDR1 cDNA showed integration, transcription, and expression of the transfered MDR1 gene. This resulted in a 20-fold increase in the resistance of MO-7e cells to paclitaxel in vitro. The expression of the MDR1 gene product was stable over a 6-month period in vitro without selection in colchicine. MO-7e and MDR1-infected MO-7e cells were transplanted into NOD SCID mice to determine whether MDR1 could confer drug resistance in vivo. A sensitive polymerase chain reaction method specific for human sequences was developed to quantitate the level of human cell engraftment in NOD SCID bone marrow (BM) cells. The percentage of human DNA in BM cells from MO-7e- transplanted mice was 10.9% and decreased to 0.7% in mice treated with paclitaxel. The percentage of human DNA in infected-MO-7e transplanted mice was 7.6% and that level was unchanged in mice treated with paclitaxel. These results show that expression of the MDR1 gene in human hematopoietic progenitor cells can confer functional drug resistance in an in vivo model.


2009 ◽  
Vol 296 (1) ◽  
pp. C65-C74 ◽  
Author(s):  
Xin Zheng ◽  
Fei Chu ◽  
Pauline M. Chou ◽  
Christine Gallati ◽  
Usawadee Dier ◽  
...  

Cathepsin L is a lysosomal enzyme thought to play a key role in malignant transformation. Recent work from our laboratory has demonstrated that this enzyme may also regulate cancer cell resistance to chemotherapy. The present study was undertaken to define the relevance of targeting cathepsin L in the suppression of drug resistance in vitro and in vivo and also to understand the mechanism(s) of its action. In vitro experiments indicated that cancer cell adaptation to increased amounts of doxorubicin over time was prevented in the presence of a cathepsin L inhibitor, suggesting that inhibition of this enzyme not only reverses but also prevents the development of drug resistance. The combination of the cathepsin L inhibitor with doxorubicin also strongly suppressed the proliferation of drug-resistant tumors in nude mice. An investigation of the underlying mechanism(s) led to the finding that the active form of this enzyme shuttles between the cytoplasm and nucleus. As a result, its inhibition stabilizes and enhances the availability of cytoplasmic and nuclear protein drug targets including estrogen receptor-α, Bcr-Abl, topoisomerase-IIα, histone deacetylase 1, and the androgen receptor. In support of this, the cellular response to doxorubicin, tamoxifen, imatinib, trichostatin A, and flutamide increased in the presence of the cathepsin L inhibitor. Together, these findings provided evidence for the potential role of cathepsin L as a target to suppress cancer resistance to chemotherapy and uncovered a novel mechanism by which protease inhibition-mediated drug target stabilization may enhance cellular visibility and, thus, susceptibility to anticancer agents.


2016 ◽  
Vol 12 (6) ◽  
pp. 1731-1745 ◽  
Author(s):  
Jonathan Lotze ◽  
Ulrike Reinhardt ◽  
Oliver Seitz ◽  
Annette G. Beck-Sickinger

Peptide-tag based labelling can be achieved by (i) enzymes (ii) recognition of metal ions or small molecules and (iii) peptide–peptide interactions and enables site-specific protein visualization to investigate protein localization and trafficking.


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