scholarly journals Hypoxia Drives Dihydropyrimidine Dehydrogenase Expression in Macrophages and Confers Chemoresistance in Colorectal Cancer

2020 ◽  
Author(s):  
Marie Malier ◽  
Magali Court ◽  
Khaldoun Gharzeddine ◽  
Marie-Hélène Laverierre ◽  
Sabrina Marsili ◽  
...  

AbstractColon adenocarcinoma is characterized by an infiltration of tumor-associated macrophages (TAMs). TAMs are associated with a chemoresistance to 5-Fluorouracil (5-FU), but the mechanisms involved are still poorly understood. In the present study, we found that macrophages specifically overexpress dihydropyrimidine dehydrogenase (DPD) in hypoxia, leading to a macrophage-induced chemoresistance to 5-FU by inactivation of the drug. Macrophage DPD expression in hypoxia is translationally controlled by the cap-dependent protein synthesis complex eIF4FHypoxic, which includes HIF-2α. We discovered that TAMs constitute the main contributors to DPD activity in human colorectal primary or secondary tumors where cancer cells do not express significant levels of DPD. Together, these findings shed light on the role of TAMs in forming chemoresistance in colorectal cancers and offer the identification of new therapeutic targets. Additionally, we report that, contrary to what is found in humans, macrophages in mice do not express DPD.

2008 ◽  
Vol 6 (9) ◽  
pp. 80
Author(s):  
T. Kantola ◽  
K. Tuppurainen ◽  
T. Hörkkö ◽  
T.J. Karttunen ◽  
S. Eskelinen ◽  
...  

2019 ◽  
Vol 20 (12) ◽  
pp. 1217-1226 ◽  
Author(s):  
Arunaksharan Narayanankutty

Background: Phosphoinositide 3-kinase (PI3Ks) is a member of intracellular lipid kinases and involved in the regulation of cellular proliferation, differentiation and survival. Overexpression of the PI3K/Akt/mTOR signalling has been reported in various forms of cancers, especially in colorectal cancers (CRC). Due to their significant roles in the initiation and progression events of colorectal cancer, they are recognized as a striking therapeutic target. Objective: The present review is aimed to provide a detailed outline on the role of PI3K/Akt/mTOR pathway in the initiation and progression events of colorectal cancers as well as its function in drug resistance. Further, the role of PI3K/Akt/mTOR inhibitors alone and in combination with other chemotherapeutic drugs, in alleviating colorectal cancer is also discussed. The review contains preclinical and clinical evidence as well as patent literature of the pathway inhibitors which are natural and synthetic in origin. Methods: The data were obtained from PubMed/Medline databases, Scopus and Google patent literature. Results: PI3K/Akt/mTOR signalling is an important event in colorectal carcinogenesis. In addition, it plays significant roles in acquiring drug resistance as well as metastatic initiation events of CRCs. Several small molecules of natural and synthetic origin have been found to be potent inhibitors of CRCs by effectively downregulating the pathway. Data from various clinical studies also support these pathway inhibitors and several among them are patented. Conclusion: Inhibitors of the PI3K/mTOR pathway have been successful for the treatment of primary and metastatic colorectal cancers, rendering the pathway as a promising clinical cancer therapeutic target.


2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Yasamin Dabiri ◽  
Sara Kalman ◽  
Clara-Marie Gürth ◽  
Jee Young Kim ◽  
Viola Mayer ◽  
...  

2019 ◽  
Vol 12 (2) ◽  
pp. 629-638
Author(s):  
N. N. Bahari ◽  
S. Y. N. Jamaludin ◽  
A. H. Jahidin ◽  
M. N. Zahary ◽  
A. B. Mohd Hilmi

The transient receptor potential vanilloid member 4 (TRPV4) is a non-selective calcium (Ca2+)-permeable channel which is widely expressed in different types of tissues including the lungs, liver, kidneys and salivary gland. TRPV4 has been shown to serve as a cellular sensor where it is involved in processes such as osmoregulation, cell volume regulation and thermoregulation. Emerging evidence suggests that TRPV4 also plays important roles in several aspects of cancer progression. Despite the reported roles of TRPV4 in several forms of cancers, the role of TRPV4 in human colorectal cancer remains largely unexplored. In the present study, we sought to establish the potential role of TRPV4 in colorectal cancer by assessing TRPV4 expression levels and investigating whether TRPV4 pharmacological modulation may alter cell proliferation, cell cycle and cell death in colorectal cancer cells. Quantitative real-time PCR analysis revealed that TRPV4 mRNA levels were significantly lower in HT-29 cells than normal colon CCD-18Co cells. However, TRPV4 mRNA was absent in HCT-116 cells. Pharmacological activation of TRPV4 with GSK1016790A significantly enhanced the proliferation of HT-29 cells while TRPV4 inhibition using RN 1734 decreased their proliferation. Increased proliferation in GSK1016790A-treated HT-29 cells was attenuated by co-treatment with RN 1734. Pharmacological modulation of TRPV4 had no effect on the cell cycle progression but promoted cell death in HT-29 cells. Taken together, these findings suggest differential TRPV4 expression levels in human colorectal cancer cells and that pharmacological modulation of TRPV4 produces distinct effects on the proliferation and induces cell death in HT-29 cells.


2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 3538-3538
Author(s):  
Ling Zhang ◽  
Jianping Song ◽  
Yiting Wang ◽  
Yaoxu Chen

3538 Background: Lysine Methyltransferase 2C (KMT2C), a member of the myeloid/lymphoid or mixed-lineage leukemia (MLL) family, possesses histone methylation activity and is involved in transcriptional co-activation. Present study has shown that KMT2C is positive correlated with better efficacy of Immune checkpoint inhibitor (ICI) in NSCLC. However, the role of KMT2C in treatment of ICI on colorectal cancer (CRC) is still unknown. Methods: NGS (Next Generation Sequencing) was performed on 1628 CRC patients. TMB of these patients were analyzed. A public accessible cohort (Samstein2018) with data from 130 CRC patients were used to investigate the correlation between KMT2C mutation and efficacy of ICI. WES and survival data of TCGA database (1099 CRC) was used to analyze prognostic effect of KMT2C mutation. Furthermore, CIBERSORT was used to analyze the tumor-infiltrating immune cells present in COAD(colon adenocarcinoma, 404 patients)from TCGA database. Results: Among 1628 CRC patient, 230(14.1%) had KMT2C mutation. TMB was positive correlated with KMT2C mutation (Mut vs. WT, 30.75 vs. 7.26 mut/Mb, p < 0.0001). The Samstein2018 cohort showed that KMT2C mutations (15.4%, 20/130) were significantly associated with better OS (Mut vs. WT, 11.5 vs. 7.5 month, HR = 0.29; 95% CI, 0.1-0.81; P = 0.012), and a higher TMB was also observed in KMT2C-Mut group (p = 1.98e-08). In TCGA, no association between KMT2C mutation and OS was observed (P = 0.23), suggesting that was not prognostic factor. Moreover, we analyzed the relationship between KMT2C mutation and immune cell infiltration through CRC TCGA database. The results showed, in COAD, KMT2C mutation was positively correlated with the abundance of CD8+ T cells (P = 0.0014), B cells (P = 0.014), M1 macrophages (P = 0.015), neutrophil (P = 0.0019) and NK cells (P = 0.043), and negatively correlated with Treg cells (p = 0.0063). Conclusions: KMT2C has an impact on the immune microenvironment and may be used as a potential positive predictor for treatment of ICI on CRC patients. The role of KMT2C in immunotherapy warrant further studies.


2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Wanjuan Xue ◽  
Yongcheng Liu ◽  
Ningning Xin ◽  
Jiyu Miao ◽  
Juan Du ◽  
...  

The study is aimed at investigating the role of Nei endonuclease VIII-like1 (NEIL1) in the pathogenesis of colorectal cancer (CRC). The human CRC (HCT116 and SW480) cells were subjected to the siRNA silencing and recombinant plasmid overexpression of NEIL1. Transfection of siNEIL1 significantly inhibited the cell growth. It also increased the Bax expression levels, while it decreased the Bcl-2 expression levels in human CRC cells, leading the Bax/Bcl-2 balance toward apoptosis. Moreover, the apoptosis was promoted through the caspase-9 signaling pathway. One the other hand, high expression of NEIL1 promoted the cell viability and reduced the apoptosis, inducing the balance of Bax/Bcl-2 in the human colon cancer cells to be antiapoptotic. In addition, the caspase-9 signaling pathway inhibited apoptosis, contrary to the results obtained by downregulating NEIL1 expression. Furthermore, NEIL1 was negatively regulated by miR-7-5p, indicating that miR-7-5p inhibited the NEIL1 expression after transcription. Overexpression of miR-7-5p reversed the effects of NEIL1 on these CRC cells. In conclusion, NEIL1 promotes the proliferation of CRC cells, which is regulated negatively by miR-7-5p. These findings suggest that NEIL1 is a potential therapeutic target for CRC.


2007 ◽  
Vol 6 (1) ◽  
pp. 128-137 ◽  
Author(s):  
Wendy L. Allen ◽  
Estelle G. McLean ◽  
John Boyer ◽  
Andrea McCulla ◽  
Peter M. Wilson ◽  
...  

2008 ◽  
Vol 2008 ◽  
pp. 1-8 ◽  
Author(s):  
Lia R. M. Bevilaqua ◽  
Janine I. Rossato ◽  
Juliana S. Bonini ◽  
Jociane C. Myskiw ◽  
Julia R. Clarke ◽  
...  

The entorhinal cortex is perhaps the area of the brain in which neurofibrillary tangles and amyloid plaques are first detectable in old age with or without mild cognitive impairment, and very particularly in Alzheimer's disease. It plays a key role in memory formation, retrieval, and extinction, as part of circuits that include the hippocampus, the amygdaloid nucleus, and several regions of the neocortex, in particular of the prefrontal cortex. Lesions or biochemical impairments of the entorhinal cortex hinder extinction. Microinfusion experiments have shown that glutamate NMDA receptors, calcium and calmodulin-dependent protein kinase II, and protein synthesis in the entorhinal cortex are involved in and required for extinction. Aging also hinders extinction; it is possible that its effect may be in part mediated by the entorhinal cortex.


2006 ◽  
Vol 14 (4) ◽  
pp. 693-702 ◽  
Author(s):  
F Comes ◽  
A Matrone ◽  
P Lastella ◽  
B Nico ◽  
F C Susca ◽  
...  

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