A Competitive Co-cultivation Assay for Cancer Drug Specificity Evaluation

2011 ◽  
Vol 16 (8) ◽  
pp. 818-824 ◽  
Author(s):  
Bachir W. El Debs ◽  
Ulrich Tschulena ◽  
Andrew D. Griffiths ◽  
Christoph A. Merten

The identification of compounds that specifically inhibit or kill cancer cells without affecting cells from healthy tissues is very challenging but very important for reducing the side effects of current cancer therapies. Hence, there is an urgent need for improved assays allowing the selectivity of a given compound to be monitored directly. The authors present an assay system based on the competitive co-cultivation of an excess of cancer cells with a small fraction of noncancer human indicator cells generating a fluorescence signal. In the absence of a specific anticancer compound, the cancer cells outgrow the indicator cells and abolish the fluorescence signal. In contrast, the presence of specific anticancer drugs (such as Tyrphostin-AG1478 or PLX4720) results in the selective growth of the indicator cells, giving rise to a strong fluorescence signal. Furthermore, the authors show that the nonspecific cytotoxic compound sodium azide kills both cancer and noncancer cells, and no fluorescence signal is obtained. Hence, this assay system favors the selection of compounds that specifically target cancer cells and decreases the probability of selecting nonspecific cytotoxic molecules. Z factors of up to 0.85 were obtained, indicating an excellent assay that can be used for high-throughput screening.

2020 ◽  
Vol 21 (19) ◽  
pp. 7345 ◽  
Author(s):  
Mohamed Zakaria Nassef ◽  
Daniela Melnik ◽  
Sascha Kopp ◽  
Jayashree Sahana ◽  
Manfred Infanger ◽  
...  

Breast cancer is the leading cause of cancer death in females. The incidence has risen dramatically during recent decades. Dismissed as an “unsolved problem of the last century”, breast cancer still represents a health burden with no effective solution identified so far. Microgravity (µg) research might be an unusual method to combat the disease, but cancer biologists decided to harness the power of µg as an exceptional method to increase efficacy and precision of future breast cancer therapies. Numerous studies have indicated that µg has a great impact on cancer cells; by influencing proliferation, survival, and migration, it shifts breast cancer cells toward a less aggressive phenotype. In addition, through the de novo generation of tumor spheroids, µg research provides a reliable in vitro 3D tumor model for preclinical cancer drug development and to study various processes of cancer progression. In summary, µg has become an important tool in understanding and influencing breast cancer biology.


2022 ◽  
Vol 23 ◽  
Author(s):  
Suman Kumar Ray ◽  
Sukhes Mukherjee

Abstract: Cancer is now also reflected as a disease of the tumor microenvironment, primarily supposed to be a decontrolled genetic and cellular expression disease. Over the past two decades, significant and rapid progress has been made in recognizing the dynamics of the tumor's microenvironment and its contribution to influencing the response to various anti-cancer therapies and drugs. Modulations in the tumor microenvironment and immune checkpoint blockade are interesting in cancer immunotherapy and drug targets. Simultaneously, the immunotherapeutic strategy can be done by modulating the immune regulatory pathway; however, the tumor microenvironment plays an essential role in suppressing the antitumor's immunity by its substantial heterogeneity. Hypoxia inducible factor (HIF) is a significant contributor to solid tumor heterogeneity and a key stressor in the tumor microenvironment to drive adaptations to prevent immune surveillance. Checkpoint inhibitors here halt the ability of cancer cells to stop the immune system from activating, and in turn, amplify your body's immune system to help destroy cancer cells. Common checkpoints that these inhibitors affect are the PD-1/PD-L1 and CTLA-4 pathways and important drugs involved are Ipilimumab and Nivolumab, mainly along with other drugs in this group. Targeting the hypoxic tumor microenvironment may provide a novel immunotherapy strategy, break down traditional cancer therapy resistance, and build the framework for personalized precision medicine and cancer drug targets. We hope that this knowledge can provide insight into the therapeutic potential of targeting Hypoxia and help to develop novel combination approaches of cancer drugs to increase the effectiveness of existing cancer therapies, including immunotherapy.


Cells ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 140
Author(s):  
Hee-Chan Yoo ◽  
Jung-Min Han

Despite the numerous investigations on resistance mechanisms, drug resistance in cancer therapies still limits favorable outcomes in cancer patients. The complexities of the inherent characteristics of tumors, such as tumor heterogeneity and the complicated interaction within the tumor microenvironment, still hinder efforts to overcome drug resistance in cancer cells, requiring innovative approaches. In this review, we describe recent studies offering evidence for the essential roles of amino acid metabolism in driving drug resistance in cancer cells. Amino acids support cancer cells in counteracting therapies by maintaining redox homeostasis, sustaining biosynthetic processes, regulating epigenetic modification, and providing metabolic intermediates for energy generation. In addition, amino acid metabolism impacts anticancer immune responses, creating an immunosuppressive or immunoeffective microenvironment. A comprehensive understanding of amino acid metabolism as it relates to therapeutic resistance mechanisms will improve anticancer therapeutic strategies.


2018 ◽  
Vol 25 (2) ◽  
pp. 123-140 ◽  
Author(s):  
Wolf-Rainer Abraham

Background: Fumitremorgins are mycotoxins but can also inhibit cancer cells and reverse their drug resistance. Objective: The bioactivity of prenylated cyclo-Trp-Pro dipeptides and their derivatives concerning their application in anti-cancer therapies will be discussed. Methods: Reports on the discovery and assessment of this class of fungal compounds are compiled from literature using Google Scholar and PubMed. The bioactivities of the natural compounds are discussed with the aim of their improvement for cancer therapy. Results: Although a number of compounds of this class have been found, only a minority of them showed bioactivity in the applied bioassays. Fumitremorgins and related compounds are active against various cancer cells but they are also mycotoxins. Some of these natural compounds can arrest cancer cells in their cell cycle and some can block ABC-transporters and reverse resistance in chemotherapy. Structure activity relationships have been deduced leading to the prediction of highly active compounds. Several easily accessible derivatives of these natural products have been discovered being highly selective and non-toxic. Conclusion: Sophisticated screening methods, high throughput screening, metabolic engineering, and synthetic biology are novel and promising technologies for the search for highly active drugs. Rapid gene sequencing in combination with engineered biosynthetic pathways should contribute substantially to novel pharmaceutics.


2021 ◽  
Author(s):  
Yogesh Goyal ◽  
Ian P. Dardani ◽  
Gianna T. Busch ◽  
Benjamin Emert ◽  
Dylan Fingerman ◽  
...  

Even amongst genetically identical cancer cells, therapy resistance often only emerges from a very small subset of those cells. Much effort has gone into uncovering the molecular differences in rare individual cells in the initial population that may allow certain cells to become therapy resistant; however, comparatively little is known about variability in the resistant outcomes themselves. Here, we develop and apply FateMap, a framework that combines DNA barcoding with single-cell RNA sequencing to reveal the fates of hundreds of thousands of clones exposed to anti-cancer therapies. We show that resistant clones emerging from single-cell-derived cancer cells adopt molecularly, morphologically, and functionally distinct fate types. These different resistant types are largely predetermined by molecular differences between cells before addition of drug and not by extrinsic cell-specific microenvironmental factors. Changes in dose and kind of drug can, however, switch the resistant fate type of an initial cell, even resulting in the generation and elimination of certain fate types. Diversity in resistant fates was observed across several single-cell-derived cancer cell lines and types treated with a variety of drugs. Cell fate diversity as a result of variability in intrinsic cell states may be a generic feature of response to external cues.


2020 ◽  
Vol 15 (6) ◽  
pp. 482-491 ◽  
Author(s):  
Milena Kostadinova ◽  
Milena Mourdjeva

Mesenchymal stem/stromal cells (MSCs) are localized throughout the adult body as a small population in the stroma of the tissue concerned. In injury, tissue damage, or tumor formation, they are activated and leave their niche to migrate to the site of injury, where they release a plethora of growth factors, cytokines, and other bioactive molecules. With the accumulation of data about the interaction between MSCs and tumor cells, the dualistic role of MSCs remains unclear. However, a large number of studies have demonstrated the natural anti-tumor properties inherent in MSCs, so this is the basis for intensive research for new methods using MSCs as a tool to suppress cancer cell development. This review focuses specifically on advanced approaches in modifying MSCs to become a powerful, precision- targeted tool for killing cancer cells, but not normal healthy cells. Suppression of tumor growth by MSCs can be accomplished by inducing apoptosis or cell cycle arrest, suppressing tumor angiogenesis, or blocking mechanisms mediating metastasis. In addition, the chemosensitivity of cancer cells may be increased so that the dose of the chemotherapeutic agent used could be significantly reduced.


2014 ◽  
Vol 9 (2) ◽  
pp. 258-263 ◽  
Author(s):  
Guang Yang ◽  
Sheng Peng ◽  
Yanling Zhang ◽  
Zhenyin Liu ◽  
Mingjian Lu ◽  
...  
Keyword(s):  

2020 ◽  
Vol 13 ◽  
Author(s):  
Selin Yılmaz ◽  
Çiğdem İçhedef ◽  
Kadriye Buşra Karatay ◽  
Serap Teksöz

Backgorund: Superparamagnetic iron oxide nanoparticles (SPIONs) have been extensively used for targeted drug delivery systems due to their unique magnetic properties. Objective: In this study, it’s aimed to develop a novel targeted 99mTc radiolabeled polymeric drug delivery system for Gemcitabine (GEM). Methods: Gemcitabine, an anticancer agent, was encapsulated into polymer nanoparticles (PLGA) together with iron oxide nanoparticles via double emulsion technique and then labeled with 99mTc. SPIONs were synthesized by reduction–coprecipitation method and encapsulated with oleic acid for surface modification. Size distribution and the morphology of the synthesized nanoparticles were caharacterized by dynamic light scattering(DLS)and scanning electron microscopy(SEM), respectively. Radiolabeling yield of SPION-PLGAGEM nanoparticles were determined via Thin Layer Radio Chromatography (TLRC). Cytotoxicity of GEM loaded SPION-PLGA were investigated on MDA-MB-231 and MCF7 breast cancer cells in vitro. Results: SEM images displayed that the average size of the drug-free nanoparticles was 40 nm and the size of the drug-loaded nanoparticles was 50 nm. The diameter of nanoparticles were determined as 366.6 nm by DLS, while zeta potential was found as-29 mV. SPION was successfully coated with PLGA, which was confirmed by FTIR. GEM encapsulation efficiency of SPION-PLGA was calculated as 4±0.16 % by means of HPLC. Radiolabeling yield of SPION-PLGA-GEM nanoparticles were determined as 97.8±1.75 % via TLRC. Cytotoxicity of GEM loaded SPION-PLGA were investigated on MDA-MB-231 and MCF7 breast cancer cells. SPION-PLGA-GEM showed high uptake on MCF-7, whilst incorporation rate was increased for both cell lines which external magnetic field application. Conclusion: 99mTc labeled SPION-PLGA nanoparticles loaded with GEM may overcome some of the obstacles in anti-cancer drug delivery because of their appropriate size, non-toxic, and supermagnetic characteristics.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ling Jin ◽  
Eun-Yeong Kim ◽  
Tae-Wook Chung ◽  
Chang Woo Han ◽  
So Young Park ◽  
...  

AbstractMost cancer cells primarily produce their energy through a high rate of glycolysis followed by lactic acid fermentation even in the presence of abundant oxygen. Pyruvate dehydrogenase kinase (PDK) 1, an enzyme responsible for aerobic glycolysis via phosphorylating and inactivating pyruvate dehydrogenase (PDH) complex, is commonly overexpressed in tumors and recognized as a therapeutic target in colorectal cancer. Hemistepsin A (HsA) is a sesquiterpene lactone isolated from Hemistepta lyrata Bunge (Compositae). Here, we report that HsA is a PDK1 inhibitor can reduce the growth of colorectal cancer and consequent activation of mitochondrial ROS-dependent apoptotic pathway both in vivo and in vitro. Computational simulation and biochemical assays showed that HsA directly binds to the lipoamide-binding site of PDK1, and subsequently inhibits the interaction of PDK1 with the E2 subunit of PDH complex. As a result of PDK1 inhibition, lactate production was decreased, but oxygen consumption was increased. Mitochondrial ROS levels and mitochondrial damage were also increased. Consistent with these observations, the apoptosis of colorectal cancer cells was promoted by HsA with enhanced activation of caspase-3 and -9. These results suggested that HsA might be a potential candidate for developing a novel anti-cancer drug through suppressing cancer metabolism.


Cancers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1866
Author(s):  
Katia A. Mesquita ◽  
Reem Ali ◽  
Rachel Doherty ◽  
Michael S. Toss ◽  
Islam Miligy ◽  
...  

FEN1 plays critical roles in long patch base excision repair (LP-BER), Okazaki fragment maturation, and rescue of stalled replication forks. In a clinical cohort, FEN1 overexpression is associated with aggressive phenotype and poor progression-free survival after platinum chemotherapy. Pre-clinically, FEN1 is induced upon cisplatin treatment, and nuclear translocation of FEN1 is dependent on physical interaction with importin β. FEN1 depletion, gene inactivation, or inhibition re-sensitizes platinum-resistant ovarian cancer cells to cisplatin. BRCA2 deficient cells exhibited synthetic lethality upon treatment with a FEN1 inhibitor. FEN1 inhibitor-resistant PEO1R cells were generated, and these reactivated BRCA2 and overexpressed the key repair proteins, POLβ and XRCC1. FEN1i treatment was selectively toxic to POLβ deficient but not XRCC1 deficient ovarian cancer cells. High throughput screening of 391,275 compounds identified several FEN1 inhibitor hits that are suitable for further drug development. We conclude that FEN1 is a valid target for ovarian cancer therapy.


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