scholarly journals A Different Approach to Cancer and Drug Resistance in Cancer: Parasites

Proceedings ◽  
2019 ◽  
Vol 40 (1) ◽  
pp. 30
Author(s):  
Armağan Caner ◽  
Ülfet Çetinkaya ◽  
Meryem Şentürk ◽  
Arzuv Charyyeva ◽  
Meryem Eren

Encephalitozoon intestinalis (E. intestinalis) is a parasite that causes opportunistic infections that can cause death in immune compromised patients. The aim of this study was to determine the effect of parasite on genes involved in host cell apoptosis. The CaCo cells were infected with E. intestinalis 50506 (ATCC) strain. Apoptosis was induced in both control and parasite-infected groups after infection. RNA isolation and cDNA extraction were then performed. Changes in the expression of genes involved in apoptotic pathways were evaluated quantitatively (qPCR) by Real-Time PCR. The obtained data were analyzed by 2-ΔΔCt method. E. intestinalis inhibits the CASP6, DR4, DR5, DCR2 genes that regulate the transcription of the genes known as the death gene of cells in CaCo cells. TP53 regulates the transcription of certain genes involved in cell death. DR4, DR5 and DCR2 are inhibited by the introduction of E. intestinalis into the cell. Caspase 6 is one of the caspases that induces apoptosis. As can be seen from the activation of these genes, E. intestinalis inhibits transcription genes in the pro-apoptotic pathway of the cell. We think that this parasite, which is commonly found in cancer patients, should be investigated for the effect of drug resistance in cancer treatment. This study was supported by Erciyes University. Project ID: TCD-2016-7042.

Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2974
Author(s):  
Haneen T. Salah ◽  
Courtney D. DiNardo ◽  
Marina Konopleva ◽  
Joseph D. Khoury

Intrinsic apoptotic pathway dysregulation plays an essential role in all cancers, particularly hematologic malignancies. This role has led to the development of multiple therapeutic agents targeting this pathway. Venetoclax is a selective BCL-2 inhibitor that has been approved for the treatment of chronic lymphoid leukemia and acute myeloid leukemia. Given the reported resistance to venetoclax, understanding the mechanisms of resistance and the potential biomarkers of response is crucial to ensure optimal drug usage and improved patient outcomes. Mechanisms of resistance to venetoclax include alterations involving the BH3-binding groove, BCL2 gene mutations affecting venetoclax binding, and activation of alternative anti-apoptotic pathways. Moreover, various potential genetic biomarkers of venetoclax resistance have been proposed, including chromosome 17p deletion, trisomy 12, and TP53 loss or mutation. This manuscript provides an overview of biomarkers that could predict treatment response to venetoclax.


Tumor Biology ◽  
2017 ◽  
Vol 39 (3) ◽  
pp. 101042831769501 ◽  
Author(s):  
Isha Rani ◽  
Bhoomika Sharma ◽  
Sandeep Kumar ◽  
Satinder Kaur ◽  
Navneet Agnihotri

5-Fluorouracil has been considered as a cornerstone therapy for colorectal cancer; however, it suffers from low therapeutic response rate and severe side effects. Therefore, there is an urgent need to increase the clinical efficacy of 5-fluorouracil. Recently, fish oil rich in n-3 polyunsaturated fatty acids has been reported to chemosensitize tumor cells to anti-cancer drugs. This study is designed to understand the underlying mechanisms of synergistic effect of fish oil and 5-fluorouracil by evaluation of tumor cell–associated markers such as apoptosis and DNA damage. The colon cancer was developed by administration of N,N-dimethylhydrazine dihydrochloride and dextran sulfate sodium salt. Further these animals were treated with 5-fluorouracil, fish oil, or a combination of both. In carcinogen-treated animals, a decrease in DNA damage and apoptotic index was observed. There was also a decrease in the expression of Fas, FasL, caspase 8, and Bax, and an increase in Bcl-2. In contrast, administration of 5-fluorouracil and fish oil as an adjuvant increased both DNA damage and apoptotic index by activation of both extrinsic and intrinsic apoptotic pathways as compared to the other groups. The increased pro-apoptotic effect by synergism of 5-fluorouracil and fish oil may be attributed to the incorporation of n-3 polyunsaturated fatty acids in membrane, which alters membrane fluidity in cancer cells. In conclusion, this study highlights that the induction of apoptotic pathway by fish oil may increase the susceptibility of tumors to chemotherapeutic regimens.


2012 ◽  
Vol 92 (1) ◽  
pp. 44-49 ◽  
Author(s):  
Pradeep Singh Chauhan ◽  
Bharat Bhushan ◽  
L.C. Singh ◽  
Ashwani Kumar Mishra ◽  
Sumita Saluja ◽  
...  

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yuan-hui Li ◽  
Shuang Shen ◽  
Tong Shao ◽  
Meng-ting Jin ◽  
Dong-dong Fan ◽  
...  

AbstractMesenchymal stem cell (MSC) therapy has become a promising treatment for liver fibrosis due to its predominant immunomodulatory performance in hepatic stellate cell inhibition and fibrosis resolution. However, the cellular and molecular mechanisms underlying these processes remain limited. In the present study, we provide insights into the functional role of bone marrow-derived MSCs (BM-MSCs) in alleviating liver fibrosis by targeting intrahepatic Ly6Chi and Ly6Clo macrophage subsets in a mouse model. Upon chronic injury, the Ly6Chi subset was significantly increased in the inflamed liver. Transplantation of BM-MSCs markedly promoted a phenotypic switch from pro-fibrotic Ly6Chi subset to restorative Ly6Clo subpopulation by secreting paracrine cytokines IL-4 and IL-10 from the BM-MSCs. The Ly6Chi/Ly6Clo subset switch significantly blocked the source of fibrogenic TGF-β, PDGF, TNF-α, and IL-1β cytokines from Ly6Chi macrophages. Unexpectedly, BM-MSCs experienced severe apoptosis and produced substantial apoptotic bodies in the fibrotic liver during the 72 h period of transplantation. Most apoptotic bodies were engulfed by Ly6Clo macrophages, and this engulfment robustly triggered MMP12 expression for fibrosis resolution through the PtdSer-MerTK-ERK signaling pathway. This paper is the first to show previously unrecognized dual regulatory functions of BM-MSCs in attenuating hepatic fibrosis by promoting Ly6Chi/Ly6Clo subset conversion and Ly6Clo macrophage restoration through secreting antifibrogenic-cytokines and activating the apoptotic pathway.


2019 ◽  
Vol 39 (5) ◽  
Author(s):  
Dongxu Zhang ◽  
Houxian Liu ◽  
Binbin Yang ◽  
Jiasheng Hu ◽  
Yue Cheng

Abstract The present study aims to evaluate the anticancer effect of L-securinine on androgen-independent prostate cancer (AIPC) DU145 cells. L-securinine (2.5, 5, and 10 μM) treatment for 24, 48 and 72 h displayed strong growth inhibitory effect on DU145 cells in a concentration and time-dependent fashion but has less toxicity toward normal androgen-dependent LNCaP cells. Hoechst 332582 staining of DU145 cells and Annexin V-FITC/ PI dual-labeling followed by flow cytometry assay identified that this growth inhibition by L-securinine would be due to the induction of apoptosis. Moreover Transwell assay revealed that L-securinine significantly inhibited the cell migration/invasion ability of DU145 cells. Furthermore, results of western blotting showed that the involvement of mitochondrial apoptotic pathway in the L-securinine-induced apoptosis of DU145 cell, as evidenced by an increase in the protein expression of Bax, cleaved caspase-9, cleaved caspase-3, cytosolic cytochrome c, and cleaved PARP, together with a unchanged cleaved caspase-8 and decreased Bcl-2 protein expression. Also, L-securinine-induced antimetastatic activity in DU145 cells was associated with decreased protein expression of MMP-2 and MMP-9 and concurrent reduction of VEGF. In addition, further studies revealed that L-securinine may inhibit the protein expression of AGTR1, p-MEK1/2, p-ERK1/2, p-STAT3, PAX2, and p-PAX2, while the expression of ERK1/2, MEK1/2, and STAT3 protein retains intact. These findings suggest that L-securinine may be a promising chemopreventive agent against AIPC.


2005 ◽  
Vol 71 (6) ◽  
pp. 3153-3157 ◽  
Author(s):  
M. Haro ◽  
F. Izquierdo ◽  
N. Henriques-Gil ◽  
I. Andrés ◽  
F. Alonso ◽  
...  

ABSTRACT Microsporidia are ubiquitous opportunistic parasites in nature infecting all animal phyla, and the zoonotic potential of this parasitosis is under discussion. Fecal samples from 124 pigeons from seven parks of Murcia (Spain) were analyzed. Thirty-six of them (29.0%) showed structures compatible with microsporidia spores by staining methods. The DNA isolated from 26 fecal samples (20.9%) of microsporidia-positive pigeons was amplified with specific primers for the four most frequent human microsporidia. Twelve pigeons were positive for only Enterocytozoon bieneusi (9.7%), 5 for Encephalitozoon intestinalis (4%), and one for Encephalitozoon hellem (0.8%). Coinfections were detected in eight additional pigeons: E. bieneusi and E. hellem were detected in six animals (4.8%); E. bieneusi was associated with E. intestinalis in one case (0.8%); and E. hellem and E. intestinalis coexisted in one pigeon. No positive samples for Encephalitozoon cuniculi were detected. The internally transcribed spacer genotype could be completed for one E. hellem-positive pigeon; the result was identical to the genotype A1 previously characterized in an E. hellem Spanish strain of human origin. To our knowledge, this is the first time that human-related microsporidia have been identified in urban park pigeons. Moreover, we can conclude that there is no barrier to microsporidia transmission between park pigeons and humans for E. intestinalis and E. hellem. This study is of environmental and sanitary interest, because children and elderly people constitute the main visitors of parks and they are populations at risk for microsporidiosis. It should also contribute to the better design of appropriate prophylactic measures for populations at risk for opportunistic infections.


2010 ◽  
Vol 22 (9) ◽  
pp. 133
Author(s):  
N. Hatzirodos ◽  
H. F. Irving-Rodgers ◽  
R. J. Rodgers

Small antral follicles <5 mm in bovine ovaries undergo one of two fates: further growth and selection to become the dominant follicle for ovulation, or atresia. Atresia can occur before, during or after selection. As follicle grow past >5 mm there is upregulation in expression of focimatrix genes and later upregulation of the LH receptor and steroidogenic enzymes, especially aromatase, in the granulosa cells. For follicles at sizes >5 mm entering atresia the granulosa cells are the first in the follicle to die. Thus expression of genes in granulosa cells is critical to the fate of the follicle. To examine granulosa cells of small follicles we collected bovine ovaries and dissected follicles, removed part of the follicle wall for subsequent classification of health or atresia, and harvested the remaining granulosa cells for RNA isolation. Follicles examined included small follicles (<5 mm), both healthy (n = 10) and atretic (n =5), and healthy large follicles (>10 mm, n = 4). RNA was hybridized to Affymetrix GeneChip Bovine Genome Arrays and the results were analysed using Partek Genomics Suite software. The number of genes which were 2 fold differentially regulated between large and small follicles by Benjamini Hochberg post hoc test (False Discovery Rate, P < 0.05) was 2408 and between healthy and atretic small follicles was 4931. The coefficient of variation (CV; SD/mean × 100) for the expression level of each gene for each group was calculated. A gene frequency distribution indicated greater heterogeneity in expression levels in small follicles in comparison to large follicles. Furthermore, the greatest variability in genes in small follicles includes those that are either up or down regulated due to atresia or growth. We therefore conclude that variability in small follicles is a consequence of alternative fates that small follicle can undergo.


1999 ◽  
Vol 43 (4) ◽  
pp. 763-768 ◽  
Author(s):  
Kien C. Ha ◽  
Theodore C. White

ABSTRACT Oral infections caused by the yeast Candida albicansare some of the most frequent and earliest opportunistic infections in human immunodeficiency virus-infected patients. The widespread use of azole antifungal drugs has led to the development of drug resistance, creating a major problem in the treatment of yeast infections in AIDS patients and other immunocompromised individuals. Several molecular mechanisms that contribute to drug resistance have been identified. InC. albicans, the ability to morphologically switch from yeast cells (blastospores) to filamentous forms (hyphae) is an important virulence factor which contributes to the dissemination ofCandida in host tissues and which promotes infection and invasion. A positive correlation between the level of antifungal drug resistance and the ability to form hyphae in the presence of azole drugs has been identified. Under hypha-inducing conditions in the presence of an azole drug, resistant clinical isolates form hyphae, while susceptible yeast isolates do not. This correlation is observed in a random sample from a population of susceptible and resistant isolates and is independent of the mechanisms of resistance.35S-methionine incorporation suggests that growth inhibition is not sufficient to explain the inhibition of hyphal formation, but it may contribute to this inhibition.


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