scholarly journals Recurrent Superenhancer of the Oncogene POU5F1B in Colorectal Cancers

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Han-chuan Tao ◽  
Cheng Wang ◽  
Ning Ma ◽  
Xun Zhu ◽  
Xiao-jun Zhou

Superenhancer usages in single cancer form such as colorectal cancer (CRC) may provide novel efficient targeting candidates. It is unclear whether CRC contains recurrent superenhancers that confer a predisposition to malignancy. We investigated the superenhancer profile of CRC cell line HCT116 and compared it to that of a healthy sigmoid colon. We found that HCT116 had lost most of the normal colon superenhancer activities but gained a new set of tumor-favoring superenhancers that facilitate tumor proliferation, growth signalling, and hypoxia resistance. Inhibiting the superenhancers by JQ-1 treatment had significantly decreased the colony formation capability of HCT116. Then, by comparing the superenhancer genes and robust CRC upregulated genes, we identified a superenhancer associated with a common CRC upregulated oncogene, POU5f1B. POU5f1B overexpression is related to the worse outcome in CRCs. Via performing ChIP-PCR in 35 clinical samples and investigating CRC anti-H3K27ac ChiP-seq public dataset consisting of 36 samples, we further identified that the superenhancer of oncogene POU5F1B is recurrently activated in CRCs, taking 62 and 72 per cent, respectively. Moreover, JQ-1 treatment successfully inhibited the POU5F1B expression in 5 out of 6 POU5F1B superenhancer-positive samples. Therefore, we concluded that the superenhancer activation of POU5F1B contributes partially to its high expression in CRCs, in addition to the well-known gene amplification aetiology.

Author(s):  
Karim Nagi ◽  
Ishita Gupta ◽  
Hamda A Al-Thawadi ◽  
Ayesha Jabeen ◽  
Mohammed I. Malk ◽  
...  

Background: Several studies have shown the presence of onco viral DNA in colorectal tumor tissues. Viral infection by onco-viruses such as Human papillomaviruses (HPVs) and Epstein–Barr virus (EBV) are well-known to be involved in the onset and/or progression of numerous human carcinomas. Methods: We explored the co-presence of high-risk HPVs and EBV in a cohort of colorectal cancer samples from Lebanon (94) and Syria (102) by PCR, immunohistochemistry and tissue microarray. Results: The results of the study point out that 54% of colorectal cancer cases in Syria are positive for high-risk HPVs, while 30% of the cases in Lebanon are positive for these viruses; the most frequent high-risk HPV types in these populations are 16, 18, 31, 33 and 35. Analysis of LMP1 showed similar results in both populations; 36% of Syrian and 31% of Lebanese samples. Additionally, we report that EBV and high-risk HPVs are co-present in these samples. In Syrian samples, EBV and HPVs are co-present in 16% of the population, however, in the Lebanese samples, 20% of the cases are positive for both EBV and HPVs; their co-presence is associated with high/intermediate grade invasive carcinomas. Conclusion: These data suggest that EBV and high-risk HPVs are co-present in human colorectal cancers where they can cooperate in the progression of these cancers. Nevertheless, further studies are needed to elucidate the role of those oncoviruses in the development of human colorectal carcinomas.


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.


2020 ◽  
Vol 16 (9) ◽  
pp. 1273-1280
Author(s):  
Giuseppina Tommonaro ◽  
Ali M. El-Hagrassi ◽  
Walid Fayad ◽  
Carmine Iodice ◽  
Kamel H. Shaker ◽  
...  

Background: Colorectal cancer represents one of the prominent causes of mortality worldwide in men and women. The objective of this study was to search for new potential anticancer compounds, both in prevention and treatment of colorectal cancer. The anticancer potential of marine bacterial extracts against Human colorectal carcinoma cell line (HCT116) was evaluated as well as the partial identification of bioactive metabolites. Methods: All bacterial extracts were tested for their cytotoxicity against HCT116 cell line by means of MTT assay. The highly cytotoxic dichloromethane extracts of marine sponge-associated bacteria Vibrio sp. and Bacillus sp. were analyzed by GC-MS. Results: Two fractions, Vib3 and Bac3, exhibited a very interesting cytotoxicity against human colorectal carcinoma (HCT116) cell line, with a percentage of cytotoxicity of 96.04 % and 29.48 %, respectively. Discussion: The GC-MS analysis revealed the presence of two major fatty acids, palmitic and oleic acids, in Vib3 fraction and fatty acid esters and phenolic compounds in Bac3 fraction. Conclusion: Based on previous literature, it may be hypothesized that the anticancer activity of bacterial extracts could be, at least partially, to the fatty acids fraction.


2019 ◽  
Vol 15 (36) ◽  
pp. 4127-4139 ◽  
Author(s):  
Yingli Yuan ◽  
Luguo Sun ◽  
Xu Wang ◽  
Jingxian Chen ◽  
Mingnan Jia ◽  
...  

Aim: To clarify the regulatory roles of GLDCV1, the first identified truncated glycine decarboxylase (GLDC), on cancer stem cells and tumorigenesis. Materials & methods: RT-PCR or RT-qPCR, immunoblotting and immunohistochemical staining were applied to assess gene expression. MTT, BrdU incorporation and colony formation assays were used to examine cell proliferation capacity. Soft agar colony formation and in vivo transplantation were applied to evaluate cellular transformation and tumorigenesis. Results & conclusion: Expression of GLDCV1 or GLDC was enhanced in non-small-cell lung cancer cell line and clinical samples. GLDCV1 overexpression induced MRC5 cell proliferation, transformation and tumorigenesis. Additionally, GLDCV1 increased lactate production and cancer stem cell marker expression and activated ERK and P38 pathways. Our study gained deeper insight into GLDC oncogene.


Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2916
Author(s):  
Hussein Al-Akhrass ◽  
Niki Christou

MiRNAs have recently become a subject of great interest within cancers and especially colorectal cancers in diagnosis, prognosis, and therapy decisions; herein we review the current literature focusing on miRNAs in colorectal cancers, and we discuss future challenges to use this tool on a daily clinical basis. In liquid biopsies, miRNAs seem easily accessible and can give important information toward each step of the management of colorectal cancers. However, it is now necessary to highlight the most sensitive and specific miRNAs for each goal thanks to multicentric prospective studies. Conclusions: by their diversity and the feasibility of their use, miRNAs are getting part of the armamentarium of healthcare management of colorectal cancers.


Sign in / Sign up

Export Citation Format

Share Document