Molecular Mechanisms and Possibilities of Overcoming Drug Resistance in Gastrointestinal Tumors

Author(s):  
M. Dietel
2020 ◽  
Vol 27 ◽  
Author(s):  
Ramarao Malla ◽  
Mohammad Amjad Kamal

: Cervical cancer (CC) is the fourth leading cancer in women in the age group 15-44 globally. Experimental as well as epidemiological studies identified that type16 and 18 HPV cause 70% of precancerous cervical lesions as well as cervical cancer worldwide by bringing about genetic as well as epigenetic changes in the host genome. The insertion of the HPV genome triggers various defense mechanisms including the silencing of tumor suppressor genes as well as activation of oncogenes associated with cancer metastatic pathway. E6 and E7 are small oncoproteins consisting of 150 and 100 amino acids respectively. These oncoproteins affect the regulation of the host cell cycle by interfering with p53 and pRb. Further these oncoproteins adversely affect the normal functions of the host cell by binding to their signaling proteins. Recent studies demonstrated that E6 and E7 oncoproteins are potential targets for CC. Therefore, this review discusses the role of E6 and E7 oncoproteins in metastasis and drug resistance as well as their regulation, early oncogene mediated signaling pathways. This review also uncovers the recent updates on molecular mechanisms of E6 and E7 mediated phytotherapy, gene therapy, immune therapy, and vaccine strategies as well as diagnosis through precision testing. Therefore, understanding the potential role of E6/E7 in metastasis and drug resistance along with targeted treatment, vaccine, and precision diagnostic strategies could be useful for the prevention and treatment of cervical cancer.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1715
Author(s):  
Macus Hao-Ran Bao ◽  
Carmen Chak-Lui Wong

Hypoxia, low oxygen (O2) level, is a hallmark of solid cancers, especially hepatocellular carcinoma (HCC), one of the most common and fatal cancers worldwide. Hypoxia contributes to drug resistance in cancer through various molecular mechanisms. In this review, we particularly focus on the roles of hypoxia-inducible factor (HIF)-mediated metabolic reprogramming in drug resistance in HCC. Combination therapies targeting hypoxia-induced metabolic enzymes to overcome drug resistance will also be summarized. Acquisition of drug resistance is the major cause of unsatisfactory clinical outcomes of existing HCC treatments. Extra efforts to identify novel mechanisms to combat refractory hypoxic HCC are warranted for the development of more effective treatment regimens for HCC patients.


2021 ◽  
Vol 22 (12) ◽  
pp. 6385
Author(s):  
Maya A. Dymova ◽  
Elena V. Kuligina ◽  
Vladimir A. Richter

Glioblastoma multiforme (GBM) is the most common and fatal primary brain tumor, is highly resistant to conventional radiation and chemotherapy, and is not amenable to effective surgical resection. The present review summarizes recent advances in our understanding of the molecular mechanisms of therapeutic resistance of GBM to already known drugs, the molecular characteristics of glioblastoma cells, and the barriers in the brain that underlie drug resistance. We also discuss the progress that has been made in the development of new targeted drugs for glioblastoma, as well as advances in drug delivery across the blood–brain barrier (BBB) and blood–brain tumor barrier (BBTB).


2017 ◽  
Vol 66 (1) ◽  
pp. S319
Author(s):  
G. Dultz ◽  
T. Shimakami ◽  
I. Antes ◽  
S. Zeuzem ◽  
C. Lange ◽  
...  

2017 ◽  
Vol 11 (12) ◽  
pp. 1151-1163 ◽  
Author(s):  
Wanli Yang ◽  
Jiaojiao Ma ◽  
Wei Zhou ◽  
Xin Zhou ◽  
Bo Cao ◽  
...  

2020 ◽  
pp. 72-82
Author(s):  
Mossa Gardaneh ◽  
Zahra Nayeri ◽  
Parvin Akbari ◽  
Mahsa Gardaneh ◽  
Hasan Tahermansouri

Background: We investigated molecular mechanisms behind astaxanthinmediated induction of apoptosis in breast cancer cell lines toward combination therapy against cancer drug resistance. Methods: Breast cancer cell lines were treated with serial concentrations of astaxanthin to determine its IC50. We used drug-design software to predict interactions between astaxanthin and receptor tyrosine kinases or other key gene products involved in intracellular signaling pathways. Changes in gene expression were examined using RT-PCR. The effect of astaxanthin-nanocarbons combinations on cancer cells was also evaluated. Results: Astaxanthin induced cell death in all three breast cancer cell lines was examined so that its IC50 in two HER2-amplifying lines SKBR3 and BT-474 stood, respectively, at 36 and 37 ?M; however, this figure for MCF-7 was significantly lowered to 23 ?M (P<0.05). Astaxanthin-treated SKBR3 cells showed apoptotic death upon co-staining. Our in silico examinations showed that some growth-promoting molecules are strongly bound by astaxanthin via their specific amino acid residues with their binding energy standing below -6 KCa/Mol. Next, astaxanthin was combined with either graphene oxide or carboxylated multi-walled carbon nanotube, with the latter affecting SKBR cell survival more extensively than the former (P<0.05). Finally, astaxanthin coinduced tumor suppressors p53 and PTEN but downregulated the expression of growth-inducing genes in treated cells. Conclusion: These findings indicate astaxanthin carries' multitarget antitumorigenic capacities and introduce the compound as a suitable candidate for combination therapy regimens against cancer growth and drug resistance. Development of animal models to elucidate interactions between the compound and tumor microenvironment could be a major step forward towards the inclusion of astaxanthin in cancer therapy trials.


2021 ◽  
Vol 11 ◽  
Author(s):  
Ying Liu ◽  
Xiang Ao ◽  
Guoqiang Ji ◽  
Yuan Zhang ◽  
Wanpeng Yu ◽  
...  

Gastric cancer (GC) is one of the most common malignant tumors of digestive systems worldwide, with high recurrence and mortality. Chemotherapy is still the standard treatment option for GC and can effectively improve the survival and life quality of GC patients. However, with the emergence of drug resistance, the clinical application of chemotherapeutic agents has been seriously restricted in GC patients. Although the mechanisms of drug resistance have been broadly investigated, they are still largely unknown. MicroRNAs (miRNAs) are a large group of small non-coding RNAs (ncRNAs) widely involved in the occurrence and progression of many cancer types, including GC. An increasing amount of evidence suggests that miRNAs may play crucial roles in the development of drug resistance by regulating some drug resistance-related proteins as well as gene expression. Some also exhibit great potential as novel biomarkers for predicting drug response to chemotherapy and therapeutic targets for GC patients. In this review, we systematically summarize recent advances in miRNAs and focus on their molecular mechanisms in the development of drug resistance in GC progression. We also highlight the potential of drug resistance-related miRNAs as biomarkers and therapeutic targets for GC patients.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Jing Ke ◽  
Chunming Gu ◽  
Heyan Zhang ◽  
Yang Liu ◽  
Wenhao Zhang ◽  
...  

Purpose. Cervical cancer is the fourth most common cancer in women worldwide and is the main cause of cancer-related deaths in women. Cisplatin (DDP) is one of the major chemotherapeutic drugs for cervical cancer patients. But, drug resistance limits the effectiveness of cancer therapy. Nucleolin (NCL) is a nucleocytoplasmic multifunctional protein involved in the development of cancer. It has been reported that NCL may be a potential target for modulation of drug resistance. However, the precise molecular mechanisms are poorly understood. Materials and Methods. Human cervical cancer Hela cells and their cisplatin-resistant cell line Hela/DDP were used in this study. The protein level of NCL in cervical cancer cells was measured by western blot analysis. Hela cells and Hela/DDP cells were transfected with NCL overexpression plasmid or NCL siRNA separately. MTT and EdU assay were performed to evaluate the cell viability and sensitivity to cisplatin. The drug efflux function of MDR1 protein was assessed by intracellular rhodamine-123 accumulation assay.The promoter activity of MDR1 was assessed by using a dual-luciferase reporter assay. Results. We found that the protein level of NCL was elevated in Hela/DDP cells. Overexpression of NCL increased cervical cancer cell proliferation and attenuated the sensitivity to cisplatin. Overexpression of NCL increased Multidrug resistance (MDR1) gene expression and drug efflux. Our results demonstrated that NCL was highly related with cisplatin resistance in cervical cancer. NCL played an important role in MDR1 gene transcription through regulation of the transcription factor YB1. Conclusion. Our findings revealed the novel role of NCL in cisplatin-resistant cervical cancer and NCL may be a potential therapeutic target for chemoresistance.


2021 ◽  
Vol 67 (1) ◽  
pp. 20-28
Author(s):  
Alexandr Chernov ◽  
Irina Baldueva ◽  
Tatyana Nekhaeva ◽  
Elvira Galimova ◽  
Diana Alaverdian ◽  
...  

In review discusses the phenomenon of drug resistance of GB in the context of the expression of ABC family transporter proteins and the processes of proliferation, angiogenesis, recurrence and death. The emphasis is on the identifying for molecular targets among growth factors, receptors, signal transduction proteins, microRNAs, transcription factors, proto-oncogenes, tumor suppressor genes and their polymorphic variants (SNPs) for the development and creation of targeted anticancer drugs.


2014 ◽  
Vol 27 (4) ◽  
pp. 489 ◽  
Author(s):  
Dusan Djokovic ◽  
Carlos Calhaz-Jorge

<p><strong>Introduction:</strong> Angiogenesis is a key factor for the successful establishment and growth of endometriotic lesions.<br /><strong>Material and Methods:</strong> We performed a literature search in PubMed and reviewed the most pertinent studies published until January 2014 and focused on the endometriosis-associated angiogenesis and/or anti-angiogenic strategies for the treatment of this gynecological disorder.<br /><strong>Results:</strong> The present review provides a concise summary of the known molecular mechanisms that promote vascularization of endometriotic lesions and may serve as potential therapeutic targets. We also present a systematic overview of the inclusive and exclusive anti-angiogenic agents that have been already studied in cell cultures, animal models and/or endometriosis patients.<br /><strong>Discussion and Conclusion:</strong> The integration of anti-angiogenic approaches in the multimodal management strategies for endometriosis patients will be conditioned by the outcomes of future assessments regarding the effectiveness of such treatments, the risk of drug resistance development and the incidence of unacceptable side effects.<br /><strong>Keywords:</strong> Angiogenesis Inhibitors/therapeutic use; Endometriosis/drug therapy.</p>


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