scholarly journals Targeting plasma membrane phosphatidylserine content to inhibit oncogenic KRAS function

2019 ◽  
Vol 2 (5) ◽  
pp. e201900431 ◽  
Author(s):  
Walaa E Kattan ◽  
Wei Chen ◽  
Xiaoping Ma ◽  
Tien Hung Lan ◽  
Dharini van der Hoeven ◽  
...  

The small GTPase KRAS, which is frequently mutated in human cancers, must be localized to the plasma membrane (PM) for biological activity. We recently showed that the KRAS C-terminal membrane anchor exhibits exquisite lipid-binding specificity for select species of phosphatidylserine (PtdSer). We, therefore, investigated whether reducing PM PtdSer content is sufficient to abrogate KRAS oncogenesis. Oxysterol-related binding proteins ORP5 and ORP8 exchange PtdSer synthesized in the ER for phosphatidyl-4-phosphate synthesized in the PM. We show that depletion of ORP5 or ORP8 reduced PM PtdSer levels, resulting in extensive mislocalization of KRAS from the PM. Concordantly, ORP5 or ORP8 depletion significantly reduced proliferation and anchorage-independent growth of multiple KRAS-dependent cancer cell lines, and attenuated KRAS signaling in vivo. Similarly, functionally inhibiting ORP5 and ORP8 by inhibiting PI4KIIIα-mediated synthesis of phosphatidyl-4-phosphate at the PM selectively inhibited the growth of KRAS-dependent cancer cell lines over normal cells. Inhibiting KRAS function through regulating PM lipid PtdSer content may represent a viable strategy for KRAS-driven cancers.

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1838
Author(s):  
Naglaa M. Ahmed ◽  
Mahmoud M. Youns ◽  
Moustafa K. Soltan ◽  
Ahmed M. Said

Scaffolds hybridization is a well-known drug design strategy for antitumor agents. Herein, series of novel indolyl-pyrimidine hybrids were synthesized and evaluated in vitro and in vivo for their antitumor activity. The in vitro antiproliferative activity of all compounds was obtained against MCF-7, HepG2, and HCT-116 cancer cell lines, as well as against WI38 normal cells using the resazurin assay. Compounds 1–4 showed broad spectrum cytotoxic activity against all these cancer cell lines compared to normal cells. Compound 4g showed potent antiproliferative activity against these cell lines (IC50 = 5.1, 5.02, and 6.6 μM, respectively) comparable to the standard treatment (5-FU and erlotinib). In addition, the most promising group of compounds was further evaluated for their in vivo antitumor efficacy against EAC tumor bearing mice. Notably, compound 4g showed the most potent in vivo antitumor activity. The most active compounds were evaluated for their EGFR inhibitory (range 53–79 %) activity. Compound 4g was found to be the most active compound against EGFR (IC50 = 0.25 µM) showing equipotency as the reference treatment (erlotinib). Molecular modeling study was performed on compound 4g revealed a proper binding of this compound inside the EGFR active site comparable to erlotinib. The data suggest that compound 4g could be used as a potential anticancer agent.


2020 ◽  
Author(s):  
Debayan Dasgupta ◽  
Dharma Pally ◽  
Deepak K. Saini ◽  
Ramray Bhat ◽  
Ambarish Ghosh

The dissemination of cancer is brought about by continuous interaction of malignant cells with their surrounding tissue microenvironment. Understanding and quantifying the remodeling of local extracellular matrix (ECM) by invading cells can therefore provide fundamental insights into the dynamics of cancer dissemination. In this paper, we use an active and untethered nanomechanical tool, realized as magnetically driven nanorobots, to locally probe a 3D tissue culture microenvironment consisting of cancerous and non-cancerous epithelia, embedded within reconstituted basement membrane (rBM) matrix. Our assay is designed to mimic the in vivo histopathological milieu of a malignant breast tumor. We find that nanorobots preferentially adhere to the ECM near cancer cells: this is due to the distinct charge conditions of the cancer-remodeled ECM. Surprisingly, quantitative measurements estimate that the adhesive force increases with the metastatic ability of cancer cell lines, while the spatial extent of the remodeled ECM was measured to be approximately 40 μm for all cancer cell lines studied here. We hypothesized and experimentally confirmed that specific sialic acid linkages specific to cancer-secreted ECM may be a major contributing factor in determining this adhesive behavior. The findings reported here can lead to promising applications in cancer diagnosis, quantification of cancer aggression, in vivo drug delivery applications, and establishes the tremendous potential of magnetic nanorobots for fundamental studies of cancer biomechanics.


Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 683
Author(s):  
Giorgia Simonetti ◽  
Carla Boga ◽  
Joseph Durante ◽  
Gabriele Micheletti ◽  
Dario Telese ◽  
...  

We synthesized five novel tryptamine derivatives characterized by the presence of an azelayl chain or of a 1,1,1-trichloroethyl group, in turn connected to another heterocyclic scaffold. The combination of tryptamin-, 1,1,1-trichloroethyl- and 2-aminopyrimidinyl- moieties produced compound 9 identified as the most active compound in hematological cancer cell lines (IC50 = 0.57–65.32 μM). Moreover, keeping constant the presence of the tryptaminic scaffold and binding it to the azelayl moiety, the compounds maintain biological activity. Compound 13 is still active against hematological cancer cell lines and shows a selective effect only on HT29 cells (IC50 = 0.006 µM) among solid tumor models. Compound 14 loses activity on all leukemic lines, while showing a high level of toxicity on all solid tumor lines tested (IC50 0.0015–0.469 µM).


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Wei Xin Cai ◽  
Li Wu Zheng ◽  
Li Ma ◽  
Hong Zhang Huang ◽  
Ru Qing Yu ◽  
...  

Tumorigenicity and metastatic activity can be visually monitored in cancer cells that were labelled with stable fluorescence. The aim was to establish and validate local and distant spread of subcutaneously previously injected fluorescence transduced human tongue cancer cell lines of epithelial and mesenchymal phenotype in nude mice. A total of 32 four-week-old male athymic Balb/c nude mice were randomly allocated into 4 groups (n=8). A single dose of 0.3 mL PBS containing 1 × 107 of four different cancer cell-lines (UM1, UM1-GFP, UM2, and UM2-RFP) was injected subcutaneously into the right side of their posterolateral back. Validity assessment of the labelled cancer cells’ tumorigenicity was assessed by physical examination, imaging, and histology four weeks after the injection. The tumor take rate of cancer cells was similar in animals injected with either parental or transduced cancer cells. Transduced cancer cells in mice were easily detectable in vivo and after cryosection using fluorescent imaging. UM1 cells showed increased tumor take rate and mean tumor volume, presenting with disorganized histopathological patterns. Fluorescence labelled epithelial and mesenchymal human tongue cancer cell lines do not change in tumorigenicity or cell phenotype after injection in vivo.


PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0246197
Author(s):  
Jorge Marquez ◽  
Jianping Dong ◽  
Chun Dong ◽  
Changsheng Tian ◽  
Ginette Serrero

Antibody-drug conjugates (ADC) are effective antibody-based therapeutics for hematopoietic and lymphoid tumors. However, there is need to identify new targets for ADCs, particularly for solid tumors and cancers with unmet needs. From a hybridoma library developed against cancer cells, we selected the mouse monoclonal antibody 33B7, which was able to bind to, and internalize, cancer cell lines. This antibody was used for identification of the target by immunoprecipitation and mass spectrometric analysis, followed by target validation. After target validation, 33B7 binding and target positivity were tested by flow cytometry and western blot analysis in several cancer cell lines. The ability of 33B7 conjugated to saporin to inhibit in vitro proliferation of PTFRN positive cell lines was investigated, as well as the 33B7 ADC in vivo effect on tumor growth in athymic mice. All flow cytometry and in vitro internalization assays were analyzed for statistical significance using a Welsh’s T-test. Animal studies were analyzed using Two-Way Analysis of Variance (ANOVA) utilizing post-hoc Bonferroni analysis, and/or Mixed Effects analysis. The 33B7 cell surface target was identified as Prostaglandin F2 Receptor Negative Regulator (PTGFRN), a transmembrane protein in the Tetraspanin family. This target was confirmed by showing that PTGFRN-expressing cells bound and internalized 33B7, compared to PTGFRN negative cells. Cells able to bind 33B7 were PTGFRN-positive by Western blot analysis. In vitro treatment PTGFRN-positive cancer cell lines with the 33B7-saporin ADC inhibited their proliferation in a dose-dependent fashion. 33B7 conjugated to saporin was also able to block tumor growth in vivo in mouse xenografts when compared to a control ADC. These findings show that screening antibody libraries for internalizing antibodies in cancer cell lines is a good approach to identify new cancer targets for ADC development. These results suggest PTGFRN is a possible therapeutic target via antibody-based approach for certain cancers.


MedChemComm ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 800-805 ◽  
Author(s):  
Jeffrey L. Henry ◽  
Matthew R. Wilson ◽  
Michael P. Mulligan ◽  
Taylor R. Quinn ◽  
Dan L. Sackett ◽  
...  

Zampanolide and dactylolide are microtubule-stabilizing polyketides possessing potent cytotoxicity towards a variety of cancer cell lines.


Author(s):  
Ruchi Singh Thakur ◽  
Bharti Ahirwar

Objective: To evaluate the cytotoxic potential of leaves and seeds of Hibiscus sabdariffa L., fruit juice of Phyllanthus emblica, rhizomes of Dryopteris cochleata and flowers of Caesalpinia decapetala (Roth) Alston along with the chemical profiling of the most toxic extract through Gas-mass spectroscopy-MS technique.Methods: The hydroalcoholic extract of the selected crude drugs was prepared by maceration method and the extracts were undergone through phytochemical analysis. The cytotoxic activity of the hydroalcoholic extract was performed against four cancer cell lines i.e. liver (HepG2), breast (MCF7), prostate (PC-3) and leukemia (HL60) using sulphorhodamine B assay. The hydroalcoholic extract of Caesalpinia decapetala flowers was profiled through using gas mass spectroscopy.Results: The results confirmed that Phyllanthus emblica inhibited HL60 cancer cells at the dose of 35.6 µg/ml and show dose-dependent growth inhibition. The flowers of Caesalpinia decapetala inhibited nearly fifty percent of HL60 cancer cells at very low dose i. e 10 µg/ml. The analysis of Caesalpinia decapetala flowers shows the presence of diterpenoid furanolactones, bufadienolides, polycyclic enones, and androsterone.Conclusion: The fruit juice of Phyllanthus emblica and flowers of Caesalpinia decapetala showed good inhibitory activity against HL60 cancer cell line. The use of Phyllanthus emblica in herbal medicine is justified. The data obtained impelled to further assess the in vivo efficacy of Caesalpinia decapetala flowers for anticancer activity.


Sign in / Sign up

Export Citation Format

Share Document