scholarly journals Pharmacological inhibition of Bax-induced cell death: Bax-inhibiting peptides and small compounds inhibiting Bax

2019 ◽  
Vol 244 (8) ◽  
pp. 621-629 ◽  
Author(s):  
Kelsey Jensen ◽  
David Jasen WuWong ◽  
Sean Wong ◽  
Mieko Matsuyama ◽  
Shigemi Matsuyama

Bax is an essential mediator of mitochondria-dependent programed cell death. Bax belongs to the Bcl-2 family of proteins and its activities are regulated through interaction with other member proteins in the Bcl-2 family. To date, several apoptosis-inducing drugs activating Bax have been developed, and some of them are already in the market as therapeutics against cancer. However, at present, there are no clinically effective pharmacological Bax inhibitors protecting essential cells. Previously, we developed Bax-Inhibiting Peptides (BIPs) that belong to the peptide group of Cell-Penetrating Peptides (CPPs). CPPs have the ability to deliver cargo molecules into the cell. In this review, we will describe the mechanism of action of BIPs together with the recent applications of BIPs in disease models in vitro and in vivo. However, BIPs have several limitations in their use to treat human diseases, and other types of Bax inhibitors need to be developed for future therapeutics. Recently, several groups reported the successful development of novel small compounds inhibiting Bax. We will review these Bax inhibitors to discuss current strategies to develop pharmacological Bax inhibitors. Impact statement Bax induces mitochondria-dependent programed cell death. While cytotoxic drugs activating Bax have been developed for cancer treatment, clinically effective therapeutics suppressing Bax-induced cell death rescuing essential cells have not been developed. This mini-review will summarize previously reported Bax inhibitors including peptides, small compounds, and antibodies. We will discuss potential applications and the future direction of these Bax inhibitors.

2019 ◽  
Vol 21 (2) ◽  
pp. 408-420 ◽  
Author(s):  
Ran Su ◽  
Jie Hu ◽  
Quan Zou ◽  
Balachandran Manavalan ◽  
Leyi Wei

Abstract Cell-penetrating peptides (CPPs) facilitate the delivery of therapeutically relevant molecules, including DNA, proteins and oligonucleotides, into cells both in vitro and in vivo. This unique ability explores the possibility of CPPs as therapeutic delivery and its potential applications in clinical therapy. Over the last few decades, a number of machine learning (ML)-based prediction tools have been developed, and some of them are freely available as web portals. However, the predictions produced by various tools are difficult to quantify and compare. In particular, there is no systematic comparison of the web-based prediction tools in performance, especially in practical applications. In this work, we provide a comprehensive review on the biological importance of CPPs, CPP database and existing ML-based methods for CPP prediction. To evaluate current prediction tools, we conducted a comparative study and analyzed a total of 12 models from 6 publicly available CPP prediction tools on 2 benchmark validation sets of CPPs and non-CPPs. Our benchmarking results demonstrated that a model from the KELM-CPPpred, namely KELM-hybrid-AAC, showed a significant improvement in overall performance, when compared to the other 11 prediction models. Moreover, through a length-dependency analysis, we find that existing prediction tools tend to more accurately predict CPPs and non-CPPs with the length of 20–25 residues long than peptides in other length ranges.


2020 ◽  
Vol 21 (5) ◽  
pp. 1856
Author(s):  
Qi Shuai ◽  
Yue Cai ◽  
Guangkuo Zhao ◽  
Xuanrong Sun

On account of their excellent capacity to significantly improve the bioavailability and solubility of chemotherapy drugs, amphiphilic block copolymer-based micelles have been widely utilized for chemotherapy drug delivery. In order to further improve the antitumor ability and to also reduce undesired side effects of drugs, cell-penetrating peptides have been used to functionalize the surface of polymer micelles endowed with the ability to target tumor tissues. Herein, we first synthesized functional polyethylene glycol-polylactic acid (PEG-PLA) tethered with maleimide at the PEG section of the block polymer, which was further conjugated with a specific peptide, the transactivating transcriptional activator (TAT), with an approved capacity of aiding translocation across the plasma membrane. Then, TAT-conjugated, paclitaxel-loaded nanoparticles were self-assembled into stable nanoparticles with a favorable size of 20 nm, and displayed a significantly increased cytotoxicity, due to their enhanced accumulation via peptide-mediated cellular association in human breast cancer cells (MCF-7) in vitro. But when further used in vivo, TAT-NP-PTX showed an acceleration of the drug’s plasma clearance rate compared with NP-PTX, and therefore weakened its antitumor activities in the mice model, because of its positive charge, its elimination by the endoplasmic reticulum system more quickly, and its targeting effect on normal cells leading towards being more toxic. So further modification of TAT-NP-PTX to shield TAT peptide’s positive charges may be a hot topic to overcome the present dilemma.


2019 ◽  
Vol 10 (10) ◽  
Author(s):  
Xiaotian Sun ◽  
James M. Angelastro ◽  
David Merino ◽  
Qing Zhou ◽  
Markus D. Siegelin ◽  
...  

Abstract Survivin (BIRC5, product of the BIRC5 gene) is highly expressed in many tumor types and has been widely identified as a potential target for cancer therapy. However, effective anti-survivin drugs remain to be developed. Here we report that both vector-delivered and cell-penetrating dominant-negative (dn) forms of the transcription factor ATF5 that promote selective death of cancer cells in vitro and in vivo cause survivin depletion in tumor cell lines of varying origins. dn-ATF5 decreases levels of both survivin mRNA and protein. The depletion of survivin protein appears to be driven at least in part by enhanced proteasomal turnover and depletion of the deubiquitinase USP9X. Survivin loss is rapid and precedes the onset of cell death triggered by dn-ATF5. Although survivin downregulation is sufficient to drive tumor cell death, survivin over-expression does not rescue cancer cells from dn-ATF5-promoted apoptosis. This indicates that dn-ATF5 kills malignant cells by multiple mechanisms that include, but are not limited to, survivin depletion. Cell-penetrating forms of dn-ATF5 are currently being developed for potential therapeutic use and the present findings suggest that they may pose an advantage over treatments that target only survivin.


RSC Advances ◽  
2018 ◽  
Vol 8 (43) ◽  
pp. 24084-24093 ◽  
Author(s):  
Qi Zhang ◽  
Jing Wang ◽  
Hao Zhang ◽  
Dan Liu ◽  
Linlin Ming ◽  
...  

Hydrophobic cell penetrating peptide PFVYLI-modified liposomes have been developed for the targeted delivery of PTX into tumors.


Peptides ◽  
2017 ◽  
Vol 87 ◽  
pp. 50-63 ◽  
Author(s):  
Azam Bolhassani ◽  
Behnaz Sadat Jafarzade ◽  
Golnaz Mardani

2020 ◽  
Author(s):  
Julia C. LeCher ◽  
Hope L. Didier ◽  
Robert L. Dickson ◽  
Lauren R. Slaughter ◽  
Juana C. Bejarano ◽  
...  

AbstractCervical cancer is the second leading cause of cancer deaths in women worldwide. Human papillomavirus (HPV) is the causative agent of nearly all forms of cervical cancer, which arises upon viral integration into the host genome and concurrent loss of regulatory gene E2. E2 protein regulates viral oncoproteins E6 and E7. Loss of E2 upon viral integration results in unregulated expression and activity of E6 and E7, which promotes carcinogenesis. Previous studies using gene-based delivery show that reintroduction of E2 into cervical cancer cell lines can reduce proliferative capacity and promote apoptosis. However, owing in part to limitations on transfection in vivo, E2 reintroduction has yet to achieve therapeutic usefulness. A promising new approach is protein-based delivery systems utilizing cell-penetrating peptides (CPPs). CPPs readily traverse the plasma membrane and are able to carry with them biomolecular ‘cargos’ to which they are attached. Though more than two decades of research have been dedicated to their development for delivery of biomolecular therapeutics, the full potential of CPPs has yet to be realized as the field is hindered by the tendency of CPP-linked cargos to be trapped in endosomes as well as having significant off-target potential in vivo. Using a CPP-adaptor system that reversibly binds cargo thereby overcoming the endosomal entrapment that hampers other CPP methods, bioactive E2 protein was delivered into living cervical cancer cells, resulting in inhibition of cellular proliferation and promotion of cell death in a time- and dose-dependent manner. The results suggest that this nucleic acid- and virus-free delivery method could be harnessed to develop novel, effective protein therapeutics for treatment of cervical cancer.


2007 ◽  
Vol 35 (4) ◽  
pp. 770-774 ◽  
Author(s):  
P. Järver ◽  
K. Langel ◽  
S. El-Andaloussi ◽  
Ü. Langel

CPPs (cell-penetrating peptides) can be defined as short peptides that are able to efficiently penetrate cellular lipid bilayers. Because of this remarkable feature, they are excellent candidates regarding alterations in gene expression. CPPs have been utilized in in vivo and in vitro experiments as delivery vectors for different bioactive cargoes. This review focuses on the experiments performed in recent years where CPPs have been used as vectors for multiple effectors of gene expression such as oligonucleotides for antisense, siRNA (small interfering RNA) and decoy dsDNA (double-stranded DNA) applications, and as transfection agents for plasmid delivery.


2015 ◽  
Vol 2015 ◽  
pp. 1-16 ◽  
Author(s):  
Yue-Wern Huang ◽  
Han-Jung Lee ◽  
Larry M. Tolliver ◽  
Robert S. Aronstam

Many viral and nonviral systems have been developed to aid delivery of biologically active molecules into cells. Among these, cell-penetrating peptides (CPPs) have received increasing attention in the past two decades for biomedical applications. In this review, we focus on opportunities and challenges associated with CPP delivery of nucleic acids and nanomaterials. We first describe the nature of versatile CPPs and their interactions with various types of cargoes. We then discussin vivoandin vitrodelivery of nucleic acids and nanomaterials by CPPs. Studies on the mechanisms of cellular entry and limitations in the methods used are detailed.


Sign in / Sign up

Export Citation Format

Share Document