scholarly journals A Comparison of Doxorubicin-Resistant Colon Cancer LoVo and Leukemia HL60 Cells: Common Features, Different Underlying Mechanisms

2021 ◽  
Vol 43 (1) ◽  
pp. 163-175
Author(s):  
Laura Locatelli ◽  
Alessandra Cazzaniga ◽  
Giorgia Fedele ◽  
Monica Zocchi ◽  
Roberta Scrimieri ◽  
...  

Chemoresistance causes cancer relapse and metastasis, thus remaining the major obstacle to cancer therapy. While some light has been shed on the underlying mechanisms, it is clear that chemoresistance is a multifaceted problem strictly interconnected with the high heterogeneity of neoplastic cells. We utilized two different human cell lines, i.e., LoVo colon cancer and promyelocytic leukemia HL60 cells sensitive and resistant to doxorubicin (DXR), largely used as a chemotherapeutic and frequently leading to chemoresistance. LoVo and HL60 resistant cells accumulate less reactive oxygen species by differently modulating the levels of some pro- and antioxidant proteins. Moreover, the content of intracellular magnesium, known to contribute to protect cells from oxidative stress, is increased in DXR-resistant LoVo through the upregulation of MagT1 and in DXR-resistant HL60 because of the overexpression of TRPM7. In addition, while no major differences in mitochondrial mass are observed in resistant HL60 and LoVo cells, fragmented mitochondria due to increased fission and decreased fusion are detected only in resistant LoVo cells. We conclude that DXR-resistant cells evolve adaptive mechanisms to survive DXR cytotoxicity by activating different molecular pathways.

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Sara Castiglioni ◽  
Alessandra Cazzaniga ◽  
Valentina Trapani ◽  
Concettina Cappadone ◽  
Giovanna Farruggia ◽  
...  

Abstract Neoplastic cells accumulate magnesium, an event which provides selective advantages and is frequently associated with TRPM7overexpression. Little is known about magnesium homeostasis in drug-resistant cancer cells. Therefore, we used the colon cancer LoVo cell model and compared doxorubicin-resistant to sensitive cells. In resistant cells the concentration of total magnesium is higher while its influx capacity is lower than in sensitive cells. Accordingly, resistant cells express lower amounts of the TRPM6 and 7, both involved in magnesium transport. While decreased TRPM6 levels are due to transcriptional regulation, post-transcriptional events are involved in reducing the amounts of TRPM7. Indeed, the calpain inhibitor calpeptin markedly increases the levels of TRPM7 in resistant cells. In doxorubicin-sensitive cells, silencing TRPM7 shifts the phenotype to one more similar to resistant cells, since in these cells silencing TRPM7 significantly decreases the influx of magnesium, increases its intracellular concentration and increases resistance to doxorubicin. On the other hand, calpain inhibition upregulates TRPM7, decreases intracellular magnesium and enhances the sensitivity to doxorubicin of resistant LoVo cells. We conclude that in LoVo cells drug resistance is associated with alteration of magnesium homeostasis through modulation of TRPM7. Our data suggest that TRPM7 expression may be an additional undisclosed player in chemoresistance.


2020 ◽  
Vol 29 ◽  
pp. 096368972095021
Author(s):  
Yanting You ◽  
Liqian Chen ◽  
Yifen Wu ◽  
Ming Wang ◽  
Hanqi Lu ◽  
...  

Heart, liver, and kidney, which are known as the essential organs for metabolism, possess the unique ability to regulate the proliferation function of the body against injury. Silibinin (SB), a natural polyphenolic flavonoid extracted from traditional herb Silybum marianum L., has been used to protect hepatocytes. Whether SB can regulate mitochondrial fission in normal cells and the underlying mechanisms remain unclear. Here, we showed that SB markedly promoted cell proliferation by facilitating G1/S transition via activating dynamin-related protein 1 (Drp1), which in turn mediated mitochondrial fission in these normal cells. SB dose-dependently increased the mitochondrial mass, mtDNA copy number, cellular adenosine triphosphate production, mitochondrial membrane potential, and reactive oxygen species in normal cells. Furthermore, SB dose-dependently increased the expression of Drp1. Blocking Drp1 abolished SB-induced mitochondrial fission. In conclusion, we demonstrate that SB promotes cell proliferation through facilitating G1/S transition by activating Drp1-mediated mitochondrial fission. This study suggests that SB is a potentially useful herbal derivative for the daily prevention of various diseases caused by impaired mitochondrial fission.


2011 ◽  
Vol 135 (3) ◽  
pp. 293-304 ◽  
Author(s):  
Wanakee J. Carr ◽  
Rebecca E. Oberley-Deegan ◽  
Yuping Zhang ◽  
Christopher C. Oberley ◽  
Larry W. Oberley ◽  
...  

Medicines ◽  
2018 ◽  
Vol 5 (4) ◽  
pp. 123 ◽  
Author(s):  
Jun-Xian Zhou ◽  
Michael Wink

Background: We studied the effect of three plant extracts (Glycyrrhiza glabra, Paeonia lactiflora, Eriobotrya japonica) and six of their major secondary metabolites (glycyrrhizic acid, 18β glycyrrhetinic acid, liquiritigenin, isoliquiritigenin, paeoniflorin, ursolic acid) on the multidrug resistant human colon cancer cell line Caco-2 and human leukemia cell line CEM/ADR 5000 as compared to the corresponding sensitive cell line CCRF-CEM, and human colon cancer cells HCT-116, which do not over-express ATP-binding cassette (ABC) transporters. Methods: The cytotoxicity of single substances in sensitive and resistant cells was investigated by MTT assay. We also applied combinations of extracts or single compounds with the chemotherapeutic agent doxorubicin or doxorubicin plus the saponin digitonin. The intracellular retention of the ABC transporter substrates rhodamine 123 and calcein was examined by flow cytometry to explore the effect of the substances on the activity of ABC transporters P-glycoprotein and MRP1. Real-time PCR was applied to analyse the gene expression changes of ABCB1, ABCC1, caspase 3, caspase 8, AhR, CYP1A1, and GSTP1 in resistant cells under the treatment of the substances. Results: All the substances moderately inhibited cell growth in sensitive and resistant cells to some degree. Whereas ursolic acid showed IC50 of 14 and 22 µM in CEM/ADR 5000 and Caco-2 cells, respectively, glycyrrhizic acid and paeoniflorin were inactive with IC50 values above 400 μM. Except for liquiritigenin and isoliquiritigenin, all the other substances reversed MDR in CEM/ADR 5000 and Caco-2 cells to doxorubicin. Ue, ga, 18ga, and urs were powerful reversal agents. In CEM/ADR 5000 cells, high concentrations of all the substances, except Paeonia lactiflora extract, increased calcein or rhodamine 123 retention in a dose-dependent manner. In Caco-2 cells, all the substances, except liquiritigenin, retained rhodamine 123 in a dose-dependent manner. We also examined the effect of the plant secondary metabolite (PSM) panel on the expression of ABCB1, ABCC1, caspase 3, caspase 8, AhR, CYP1A1, and GSTP1 genes in MDR cells. Conclusions: The extracts and individual PSM could reverse MDR in CEM/ADR 5000 and Caco-2 cells, which overexpress ABC transporters, in two- and three-drug combinations. Most of the PSM also inhibited the activity of ABC transporters to some degree, albeit at high concentrations. Ue, ga, 18ga, and urs were identified as potential multidrug resistance (MDR) modulator candidates, which need to be characterized and validated in further studies.


2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Heui Min Lim ◽  
Jongsung Lee ◽  
Myeong Jin Nam ◽  
See-Hyoung Park

Acetylshikonin, a naphthoquinone, is a pigment compound derived from Arnebia sp., which is known for its anti-inflammatory potential. However, its anticarcinogenic effect has not been well investigated. Thus, in this study, we focused on investigating its apoptotic effects against HCT-15 and LoVo cells, which are human colorectal cancer cells. MTT assay, cell counting assay, and colony formation assay have shown acetylshikonin treatment induced cytotoxic and antiproliferative effects against colorectal cancer cells in a dose- and time-dependent manner. DNA fragmentation was observed via terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Also, the increase of subG1 phase in cell cycle arrest assay and early/late apoptotic rates in annexin V/propidium iodide (PI) double staining assay was observed, which indicates an apoptotic potential of acetylshikonin against colorectal cancer cells. 2 ′ ,7 ′ -Dichlorofluorescin diacetate (DCF-DA) staining was used to evaluate reactive oxygen species (ROS) generation in acetylshikonin-treated colorectal cancer cells. Fluorescence-activated cell sorting (FACS) analysis showed that acetylshikonin induced an increase in reactive oxygen species (ROS) levels and apoptotic rate in a dose- and time-dependent manner in HCT-15 and LoVo cells. In contrast, cotreatment with N-acetyl cysteine (NAC) has reduced ROS generation and antiproliferative effects in colorectal cancer cells. Western blotting analysis showed that acetylshikonin treatment induced increase of cleaved PARP, γH2AX, FOXO3, Bax, Bim, Bad, p21, p27, and active forms of caspase-3, caspase-7, caspase-9, caspase-6, and caspase-8 protein levels, while those of inactive forms were decreased. Also, the expressions of pAkt, Bcl-2, Bcl-xL, peroxiredoxin, and thioredoxin 1 were decreased. Furthermore, western blotting analysis of cytoplasmic and nuclear fractionated proteins showed that acetylshikonin treatment induced the nuclear translocation of FOXO3, which might result from DNA damage by the increased intracellular ROS level. This study represents apoptotic potential of acetylshikonin against colorectal cancer cells via translocation of FOXO3 to the nucleus and upregulation of ROS generation.


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