| 1. |
- Azharuddin, Mohammad, et al.
(författare)
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Dissecting multi drug resistance in head and neck cancer cells using multicellular tumor spheroids
- 2019
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- One of the hallmarks of cancers is their ability to develop resistance against therapeutic agents. Therefore, developing effective in vitro strategies to identify drug resistance remains of paramount importance for successful treatment. One of the ways cancer cells achieve drug resistance is through the expression of efflux pumps that actively pump drugs out of the cells. To date, several studies have investigated the potential of using 3-dimensional (3D) multicellular tumor spheroids (MCSs) to assess drug resistance; however, a unified system that uses MCSs to differentiate between multi drug resistance (MDR) and non-MDR cells does not yet exist. In the present report we describe MCSs obtained from post-diagnosed, pre-treated patient-derived (PTPD) cell lines from head and neck squamous cancer cells (HNSCC) that often develop resistance to therapy. We employed an integrated approach combining response to clinical drugs and screening cytotoxicity, monitoring real-time drug uptake, and assessing transporter activity using flow cytometry in the presence and absence of their respective specific inhibitors. The report shows a comparative response to MDR, drug efflux capability and reactive oxygen species (ROS) activity to assess the resistance profile of PTPD MCSs and two-imensional (2D) monolayer cultures of the same set of cell lines. We show that MCSs provide a robust and reliable in vitro model to evaluate clinical relevance. Our proposed strategy can also be clinically applicable for profiling drug resistance in cancers with unknown resistance profiles, which consequently can indicate benefit from downstream therapy.
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| 2. |
- Cieslar-Pobuda, Artur, et al.
(författare)
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Cell Type Related Differences in Staining with Pentameric Thiophene Derivatives
- 2014
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Ingår i: Cytometry Part A. - : John Wiley & Sons. - 1552-4922 .- 1552-4930. ; 85A:7, s. 628-635
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Tidskriftsartikel (refereegranskat)abstract
- Fluorescent compounds capable of staining cells selectively without affecting their viability are gaining importance in biology and medicine. Recently, a new family of optical dyes, denoted luminescent conjugated oligothiophenes (LCOs), has emerged as an interesting class of highly emissive molecules for studying various biological phenomena. Properly functionalized LCOs have been utilized for selective identification of disease-associated protein aggregates and for selective detection of distinct cells. Herein, we present data on differential staining of various cell types, including cancer cells. The differential staining observed with newly developed pentameric LCOs is attributed to distinct side chain functionalities along the thiophene backbone. Employing flow cytometry and fluorescence microscopy we examined a library of LCOs for stainability of a variety of cell lines. Among tested dyes we found promising candidates that showed strong or moderate capability to stain cells to different extent, depending on target cells. Hence, LCOs with diverse imidazole motifs along the thiophene backbone were identified as an interesting class of agents for staining of cancer cells, whereas LCOs with other amino acid side chains along the backbone showed a complete lack of staining for the cells included in the study. Furthermore, for p-HTMI,a LCO functionalized with methylated imidazole moieties, the staining was dependent on the p53 status of the cells, indicating that the molecular target for the dye is a cellular component regulated by p53. We foresee that functionalized LCOs will serve as a new class of optical ligands for fluorescent classification of cells and expand the toolbox of reagents for fluorescent live imaging of different cells.
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| 3. |
- Cieślar-Pobuda, Artur, et al.
(författare)
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The expression pattern of PFKFB3 enzyme distinguishes between induced-pluripotent stem cells and cancer stem cells.
- 2015
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Ingår i: Oncotarget. - Albany, NY, USA : Impact Journals LLC. - 1949-2553. ; 6:30, s. 29753--29770
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Tidskriftsartikel (refereegranskat)abstract
- Induced pluripotent stem cells (iPS) have become crucial in medicine and biology. Several studies indicate their phenotypic similarities with cancer stem cells (CSCs) and a propensity to form tumors. Thus it is desirable to identify a trait which differentiates iPS populations and CSCs. Searching for such a feature, in this work we compare the restriction (R) point-governed regulation of cell cycle progression in different cell types (iPS, cancer, CSC and normal cells) based on the expression profile of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase3 (PFKFB3) and phosphofructokinase (PFK1). Our study reveals that PFKFB3 and PFK1 expression allows discrimination between iPS and CSCs. Moreover, cancer and iPS cells, when cultured under hypoxic conditions, alter their expression level of PFKFB3 and PFK1 to resemble those in CSCs. We also observed cell type-related differences in response to inhibition of PFKFB3. This possibility to distinguish CSC from iPS cells or non-stem cancer cells by PFKB3 and PFK1 expression improves the outlook for clinical application of stem cell-based therapies and for more precise detection of CSCs.
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| 4. |
- Hashemi, Mohammad, et al.
(författare)
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Functional Polymorphisms of FAS and FASL Gene andRisk of Breast Cancer – Pilot Study of 134 Cases
- 2013
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 8:1, s. e53075-
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Tidskriftsartikel (refereegranskat)abstract
- Fas/Fas ligand (FasL) system is one of the key apoptotic signaling entities in the extrinsic apoptotic pathway. De-regulation of this pathway, i.e. by mutations may prevent the immune system from the removal of newly-formed tumor cells, and thus lead to tumor formation. The present study investigated the association between −1377 G/A (rs2234767) and −670 A/G (rs1800682) polymorphisms in Fas as well as single nucleotide polymorphisms INV2nt −124 A/G (rs5030772) and −844 C/T (rs763110) in FasL in a sample of Iranian patients with breast cancer. This case-control study was done on 134 breast cancer patients and 152 normal women. Genomic DNA was extracted from whole blood samples. The polymorphisms were determined by using tetra-ARMS-PCR method. There was no significant difference in the genotype distribution of FAS rs2234767 polymorphism between cases and controls. FAS rs1800682, FASL rs5030772, and FASL rs763110 genotypes showed significant associations with an increasing risk of breast cancer (odds ratio OR = 3.18, P = 0.019; OR = 5.08, P = 0.012; OR = 2.40, P = 0.024, respectively). In conclusion, FAS rs2234767 was not associated with breast cancer risk. Though, FAS rs1800682, FASL rs5030772, and FASL rs763110 polymorphisms were associated with the risk of breast cancer in the examined population.
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| 5. |
- Jain, Mayur Vilas, 1987-, et al.
(författare)
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Inhibition of miR301 enhances Akt-mediated cell proliferation by accumulation of PTEN in nucleus and its effects on cell-cycle regulatory proteins
- 2016
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 7:15, s. 20953-20965
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Tidskriftsartikel (refereegranskat)abstract
- Micro-RNAs (miRs) represent an innovative class of genes that act as regulators of gene expression. Recently, the aberrant expression of several miRs has been associated with different types of cancers. In this study, we show that miR301 inhibition influences PI3K-Akt pathway activity. Akt overexpression in MCF7 and MDAMB468 cells caused downregulation of miR301 expression. This effect was confirmed by co-transfection of miR301-modulators in the presence of Akt. Cells overexpressing miR301-inhibitor and Akt, exhibited increased migration and proliferation. Experimental results also confirmed PI3K, PTEN and FoxF2 as regulatory targets for miR301. Furthermore, Akt expression in conjunction with miR301-inhibitor increased nuclear accumulation of PTEN, thus preventing it from downregulating the PI3K-signalling. In summary, our data emphasize the importance of miR301 inhibition on PI3K-Akt pathway-mediated cellular functions. Hence, it opens new avenues for the development of new anti-cancer agents preferentially targeting PI3K-Akt pathway.
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| 6. |
- Jain, Mayur Vilas, et al.
(författare)
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Interconnections between apoptotic, autophagic and necrotic pathways : implications for cancer therapy development
- 2013
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Ingår i: Journal of Cellular and Molecular Medicine (Print). - : Wiley-Blackwell. - 1582-1838 .- 1582-4934. ; 17:1, s. 12-29
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Forskningsöversikt (refereegranskat)abstract
- The rapid accumulation of knowledge on apoptosis regulation in the 1990s was followed by the development of several experimental anticancer- and anti-ischaemia (stroke or myocardial infarction) drugs. Activation of apoptotic pathways or the removal of cellular apoptotic inhibitors has been suggested to aid cancer therapy and the inhibition of apoptosis was thought to limit ischaemia-induced damage. However, initial clinical studies on apoptosis-modulating drugs led to unexpected results in different clinical conditions and this may have been due to co-effects on non-apoptotic interconnected cell death mechanisms and the yin-yang role of autophagy in survival versus cell death. In this review, we extend the analysis of cell death beyond apoptosis. Upon introduction of molecular pathways governing autophagy and necrosis (also called necroptosis or programmed necrosis), we focus on the interconnected character of cell death signals and on the shared cell death processes involving mitochondria (e.g. mitophagy and mitoptosis) and molecular signals playing prominent roles in multiple pathways (e.g. Bcl2-family members and p53). We also briefly highlight stress-induced cell senescence that plays a role not only in organismal ageing but also offers the development of novel anticancer strategies. Finally, we briefly illustrate the interconnected character of cell death forms in clinical settings while discussing irradiation-induced mitotic catastrophe. The signalling pathways are discussed in their relation to cancer biology and treatment approaches.
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| 7. |
- Jain, Mayur Vilas, 1987-
(författare)
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PKB/Akt kinase localization and role in stemness maintenance in cancer
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cancer incidence rates have increased over the last decade. Currently available therapies are only moderately effective in targeting cancer cells. Established cancer treatment protocols fail to eliminate populations of cancer stem cells (CSCs), which develop resistance against the chemotherapeutic drugs and lead to cancer recurrence. Therefore, understanding the mechanisms by which CSCs resist drugs and identifying molecular markers are both necessary to further improve prognosis and to develop new treatment strategies. Increased protein kinase B/Akt1 gene expression and/or activity have been found increased in majority of cancer types. Akt1 is a key player in PI3K-AktmTOR pathway that is vital for cell survival, proliferation, migration, invasion, metastasis, angiogenesis and apoptosis. In this study, we investigated a series of novel markers to improve the characterization of CSCs, with particular focus the roles of Akt in CSC maintenance and the regulatory role of micro-RNA (miR) in cancer cells. While utilizing in breast cancer cells as models, we found that luminescent conjugated oligothiophenes (LCOs), p-HTMI and p-HTAA have the potential to differentially stain various subpopulations of cancer cells, presumably also CSCs among breast cancer cells. However, further studies are needed to confirm these results. Additionally, when we investigated the effect of Akt intracellular compartmentalization on CSC development, the results revealed that nuclear Akt enhances CSC proliferation (ALDH +/High CD44+/High/CD24-/Low) and clonogenicity, which was counter examined and confirmed by using the Aktspecific inibitor triciribine. Furthermore, while investigating the impact of Akt on miR regulation in cancer cells, we found that Akt overexpression decreased.
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| 8. |
- Melissaridou, Styliani, et al.
(författare)
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The effect of 2D and 3D cell cultures on treatment response, EMT profile and stem cell features in head and neck cancer 11 Medical and Health Sciences 1112 Oncology and Carcinogenesis
- 2019
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Ingår i: Cancer Cell International. - : Springer Science and Business Media LLC. - 1475-2867. ; 19:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Head and Neck Squamous Cell Carcinoma (HNSCC) tumors are often resistant to therapies. Therefore searching for predictive markers and new targets for treatment in clinically relevant in vitro tumor models is essential. Five HNSCC-derived cell lines were used to assess the effect of 3D culturing compared to 2D monolayers in terms of cell proliferation, response to anti-cancer therapy as well as expression of EMT and CSC genes. Methods: The viability and proliferation capacity of HNSCC cells as well as induction of apoptosis in tumor spheroids cells after treatment was assessed by MTT assay, crystal violet- and TUNEL assay respectively. Expression of EMT and CSC markers was analyzed on mRNA (RT-qPCR) and protein (Western blot) level. Results: We showed that HNSCC cells from different tumors formed spheroids that differed in size and density in regard to EMT-associated protein expression and culturing time. In all spheroids, an up regulation of CDH1, NANOG and SOX2 was observed in comparison to 2D but changes in the expression of EGFR and EMT markers varied among the cell lines. Moreover, most HNSCC cells grown in 3D showed decreased sensitivity to cisplatin and cetuximab (anti-EGFR) treatment. Conclusions: Taken together, our study points at notable differences between these two cellular systems in terms of EMT-associated gene expression profile and drug response. As the 3D cell cultures imitate the in vivo behaviour of neoplastic cells within the tumor, our study suggest that 3D culture model is superior to 2D monolayers in the search for new therapeutic targets.
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| 9. |
- Rajendran, Vijayalakshmi, et al.
(författare)
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In vitro tumorigenic assay : colony forming assay for cancer stem cells
- 2018
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Ingår i: Methods in Molecular Biology. - New York, NY : Springer New York. - 1064-3745. ; 1692, s. 89-95, s. 89-95
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Bokkapitel (refereegranskat)abstract
- Colony forming or clonogenic assay is an in vitro quantitative technique to examine the capability of a single cell to grow into a large colony through clonal expansion. Clonogenic activity is a sensitive indicator of undifferentiated cancer stem cells. Here, we described the colony forming ability of the isolated breast cancer stem cells from the total population of cancer cells using double-layered, soft agarose-based assay. This method demonstrates that cancer stem cells can survive and generate colony growth in an anchorage-independent culture model. The 0.005% crystal violet solution is used in this assay to visualize the generated colonies.
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| 10. |
- Rajendran, Vijayalakshmi, et al.
(författare)
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Stem cell aging and wound healing
- 2021
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Ingår i: Stem Cells and Aging. - 9780128200711 ; , s. 53-60
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Bokkapitel (refereegranskat)abstract
- Aging is a natural process that promotes different pathologies and progressive functional losses of cells and tissues. Aging impacts stem cell reserve and function negatively, resulting in compromising tissue regeneration. Stem cell aging significantly impairs wound healing properties of different tissues due to the age-related aberrant changes like increased proinflammatory cytokines, accumulation of toxic metabolites, and senescence-associated molecules in the systemic milieu. The cascade of improper structural alterations leading to fibrosis is a serious concern in aged tissues upon injury due to the increased thickness/stiffness of extracellular matrix intermediated by matrix metalloproteinases. The aged-associated defects in the stem cell function can be revived by applying various exogenous interventions aiming at upregulating optimal reparative conditions for aged tissues. Thus, this chapter briefly covers the factors linked to impaired wound healing due to stem cell aging and enlists alternative treatment strategies to regulate tissue regeneration in aging.
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| 11. |
- Shakeri, Raheleh, et al.
(författare)
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Role of the salt bridge between glutamate 546 and arginine 907 in preservation of autoinhibited form of Apaf-1
- 2015
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Ingår i: International Journal of Biological Macromolecules. - : ELSEVIER SCIENCE BV. - 0141-8130 .- 1879-0003. ; 81, s. 370-374
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Tidskriftsartikel (refereegranskat)abstract
- Apaf-1, the key element of apoptotic mitochondrial pathway, normally exists in an auto-inhibited form inside the cytosol. WRD-domain of Apaf-1 has a critical role in the preservation of auto-inhibited form; however the underlying mechanism is unclear. It seems the salt bridges between WRD and NOD domains are involved in maintaining the inactive conformation of Apaf-1. At the present study, we have investigated the effect of E546-R907 salt bridge on the maintenance of auto-inhibited form of human Apaf-1. E546 is mutated to glutamine (Q) and arginine (R). Over-expression of wild type Apaf-1 and its E546Q and E546R variants in HEK293T cells does not induce apoptosis unlike - HL-60 cancer cell line. In vitro apoptosome formation assay showed that all variants are cytochrome c and dATP dependent to form apoptosome and activate endogenous procaspase-9 in Apaf-1-knockout MEF cell line. These results suggest that E546 is not a critical residue for preservation of auto-inhibited Apaf-1. Furthermore, the behavior of Apaf-1 variants for in vitro apoptosome formation in HEK293T cell is similar to exogenous wild type Apaf-1. Wild type and its variants can form apoptosome in HEK293T cell with different procaspase-3 processing pattern in the presence and absence of exogenous cytochrome c and dATP. (C) 2015 Elsevier B.V. All rights reserved.
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| 12. |
- Subramaniam, Agatheeswaran, et al.
(författare)
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Lysine-specific demethylase 1A (LSD1) restricts ex vivo propagation of human HSCs and is a target of UM171
- 2020
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Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 136:19, s. 2151-2161
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Tidskriftsartikel (refereegranskat)abstract
- Culture conditions in which hematopoietic stem cells (HSCs) can be expanded for clinical benefit are highly sought after. Here, we report that inhibition of the epigenetic regulator Lysine-specific histone demethylase 1A (LSD1) induces a rapid expansion of human cord blood derived CD34+ cells and promotes in vitro propagation of long-term repopulating HSCs by preventing differentiation. The phenotype and molecular characteristics of cells treated with LSD1 inhibitors were highly similar to cells treated with UM171, an agent promoting expansion of HSCs through undefined mechanisms, and currently tested in clinical trials. Strikingly, we found that LSD1 as well as other members of the LSD1 containing chromatin remodeling complex CoREST are rapidly poly-ubiquitinated and degraded upon UM171 treatment. CRISPR/Cas9 depletion of the CoREST core member, RCOR1, resulted in expansion of CD34+ cells similar to LSD1 inhibition and UM171. Taken together, LSD1 and CoREST restrict HSC expansion, and are principal targets of UM171, forming a mechanistic basis for the HSC promoting activity of UM171.
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| 13. |
- Vilas Jain, Mayur, et al.
(författare)
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Nuclear localized Akt enhances breast cancer stem-like cells through counter-regulation of p21(Waf1/Cip1) and p27(kip1)
- 2015
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Ingår i: Cell Cycle. - : Taylor and Francis: STM, Behavioural Science and Public Health Titles. - 1538-4101 .- 1551-4005. ; 14:13, s. 2109-2120
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Tidskriftsartikel (refereegranskat)abstract
- Cancer stem-like cells (CSCs) are a rare subpopulation of cancer cells capable of propagating the disease and causing cancer recurrence. In this study, we found that the cellular localization of PKB/Akt kinase affects the maintenance of CSCs. When Akt tagged with nuclear localization signal (Akt-NLS) was overexpressed in SKBR3 and MDA-MB468 cells, these cells showed a 10-15% increase in the number of cells with CSCs enhanced ALDH activity and demonstrated a CD44(+High)/CD24(-Low) phenotype. This effect was completely reversed in the presence of Akt-specific inhibitor, triciribine. Furthermore, cells overexpressing Akt or Akt-NLS were less likely to be in G0/G1 phase of the cell cycle by inactivating p21(Waf1/Cip1) and exhibited increased clonogenicity and proliferation as assayed by colony-forming assay (mammosphere formation). Thus, our data emphasize the importance the intracellular localization of Akt has on stemness in human breast cancer cells. It also indicates a new robust way for improving the enrichment and culture of CSCs for experimental purposes. Hence, it allows for the development of simpler protocols to study stemness, clonogenic potency, and screening of new chemotherapeutic agents that preferentially target cancer stem cells. Summary: The presented data, (i) shows new, stemness-promoting role of nuclear Akt/PKB kinase, (ii) it underlines the effects of nuclear Akt on cell cycle regulation, and finally (iii) it suggests new ways to study cancer stem-like cells.
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