scholarly journals Insulin enhancement of the antitumor activity of chemotherapeutic agents in colorectal cancer is linked with downregulating PIK3CA and GRB2

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Siddarth Agrawal ◽  
Marta Woźniak ◽  
Mateusz Łuc ◽  
Sebastian Makuch ◽  
Ewa Pielka ◽  
...  

Abstract The present state of cancer chemotherapy is unsatisfactory. New anticancer drugs that marginally improve the survival of patients continue to be developed at an unsustainably high cost. The study aimed to elucidate the effects of insulin (INS), an inexpensive drug with a convincing safety profile, on the susceptibility of colon cancer to chemotherapeutic agents: 5-fluorouracil (FU), oxaliplatin (OXA), irinotecan (IRI), cyclophosphamide (CPA) and docetaxel (DOC). To examine the effects of insulin on cell viability and apoptosis, we performed an in vitro analysis on colon cancer cell lines Caco-2 and SW480. To verify the results, we performed in vivo analysis on mice bearing MC38 colon tumors. To assess the underlying mechanism of the therapy, we examined the mRNA expression of pathways related to the signaling downstream of insulin receptors (INSR). Moreover, we performed Western blotting to confirm expression patterns derived from the genetic analysis. For the quantification of circulating tumor cells in the peripheral blood, we used the maintrac method. The results of our study show that insulin-pretreated colon cancer cells are significantly more susceptible to commonly used chemotherapeutics. The apoptosis ratio was also enhanced when INS was administered complementary to the examined drugs. The in vivo study showed that the combination of INS and FU resulted in significant inhibition of tumor growth and reduction of the number of circulating tumor cells. This combination caused a significant downregulation of the key signaling substrates downstream of INSR. The results indicate that the downregulation of PIK3CA (phosphatidylinositol 3-kinase catalytic subunit alpha), which plays a critical role in cell signaling and GRB2 (growth factor receptor-bound protein 2), a regulator of cell proliferation and differentiation may be responsible for the sensitizing effect of INS. These findings were confirmed at protein levels by Western blotting. In conclusion, these results suggest that INS might be potentially applied to clinical use to enhance the therapeutic effectiveness of chemotherapeutic drugs. The findings may become a platform for the future development of new and inexpensive strategies for the clinical chemotherapy of tumors.

2019 ◽  
Vol 65 (5) ◽  
pp. 760-765
Author(s):  
Margarita Tyndyk ◽  
Irina Popovich ◽  
A. Malek ◽  
R. Samsonov ◽  
N. Germanov ◽  
...  

The paper presents the results of the research on the antitumor activity of a new drug - atomic clusters of silver (ACS), the colloidal solution of nanostructured silver bisilicate Ag6Si2O7 with particles size of 1-2 nm in deionized water. In vitro studies to evaluate the effect of various ACS concentrations in human tumor cells cultures (breast cancer, colon carcinoma and prostate cancer) were conducted. The highest antitumor activity of ACS was observed in dilutions from 2.7 mg/l to 5.1 mg/l, resulting in the death of tumor cells in all studied cell cultures. In vivo experiments on transplanted Ehrlich carcinoma model in mice consuming 0.75 mg/kg ACS with drinking water revealed significant inhibition of tumor growth since the 14th day of experiment (maximally by 52% on the 28th day, p < 0.05) in comparison with control. Subcutaneous injections of 2.5 mg/kg ACS inhibited Ehrlich's tumor growth on the 7th and 10th days of the experiment (p < 0.05) as compared to control.


2018 ◽  
Vol 218 (1) ◽  
pp. 317-332 ◽  
Author(s):  
Li Qiang ◽  
Hong Cao ◽  
Jing Chen ◽  
Shaun G. Weller ◽  
Eugene W. Krueger ◽  
...  

The process by which tumor cells mechanically invade through surrounding stroma into peripheral tissues is an essential component of metastatic dissemination. The directed recruitment of the metalloproteinase MT1-MMP to invadopodia plays a critical role in this invasive process. Here, we provide mechanistic insight into MT1-MMP cytoplasmic tail binding protein 1 (MTCBP-1) with respect to invadopodia formation, matrix remodeling, and invasion by pancreatic tumor cells. MTCBP-1 localizes to invadopodia and interacts with MT1-MMP. We find that this interaction displaces MT1-MMP from invadopodia, thereby attenuating their number and function and reducing the capacity of tumor cells to degrade matrix. Further, we observe an inverse correlation between MTCBP-1 and MT1-MMP expression both in cultured cell lines and human pancreatic tumors. Consistently, MTCBP-1–expressing cells show decreased ability to invade in vitro and metastasize in vivo. These findings implicate MTCBP-1 as an inhibitor of the metastatic process.


2021 ◽  
Author(s):  
Julia Bonnet ◽  
Lise Rigal ◽  
Odile Mondesert ◽  
Renaud Morin ◽  
Gaelle Corsaut ◽  
...  

Abstract Background Cancer cell aggregation is a key process involved in the formation of tumor cell clusters. It has recently been shown that clusters of circulating tumor cells (CTCs) have an increased metastatic potential compared to isolated circulating tumor cells. Several widely used chemotherapeutic agents that target the cytoskeleton microtubules and cause cell cycle arrest at mitosis have been reported to modulate CTC number or the size of CTC clusters. Results In this study, we investigated in vitro the impact of mitotic arrest on the ability of breast tumor cells to form clusters. By using live imaging and quantitative image analysis, we found that MCF-7 cancer cell aggregation is compromised upon incubation with paclitaxel or vinorelbine, two chemotherapeutic drugs that target microtubules. In line with these results, we observed that MCF-7 breast cancer cells experimentally synchronized and blocked in metaphase aggregated poorly and formed loose clusters. To monitor clustering at the single-cell scale, we next developed and validated an in vitro assay based on live video-microscopy and custom-designed micro-devices. The study of cluster formation from MCF-7 cells that express the fluorescent marker LifeAct-mCherry using this new assay allowed showing that substrate anchorage-independent clustering of MCF-7 cells was associated with the formation of actin-dependent highly dynamic cell protrusions. Metaphase-synchronized and blocked cells did not display such protrusions, and formed very loose clusters that failed to compact. Conclusions Altogether, our results suggest that mitotic arrest induced by microtubule-targeting anticancer drugs prevents cancer cell clustering and therefore, could reduce the metastatic potential of circulating tumor cells.


2021 ◽  
Author(s):  
Xin Peng ◽  
Shaolu Zhang ◽  
Wenhui Jiao ◽  
Zhenxing Zhong ◽  
Yuqi Yang ◽  
...  

Abstract Background: The critical role of phosphoinositide 3-kinase (PI3K) activation in tumor cell biology has prompted massive efforts to develop PI3K inhibitors (PI3Kis) for cancer therapy. However, recent results from clinical trials have shown only a modest therapeutic efficacy of single-agent PI3Kis in solid tumors. Targeting autophagy has controversial context-dependent effects in cancer treatment. As a FDA-approved lysosomotropic agent, hydroxychloroquine (HCQ) has been well tested as an autophagy inhibitor in preclinical models. Here, we elucidated the novel mechanism of HCQ alone or in combination with PI3Ki BKM120 in the treatment of cancer.Methods: The antitumor effects of HCQ and BKM120 on three different types of tumor cells were assessed by in vitro PrestoBlue assay, colony formation assay and in vivo zebrafish and nude mouse xenograft models. The involved molecular mechanisms were investigated by MDC staining, LC3 puncta formation assay, immunofluorescent assay, flow cytometric analysis of apoptosis and ROS, qRT-PCR, Western blot, comet assay, homologous recombination (HR) assay and immunohistochemical staining. Results: HCQ significantly sensitized cancer cells to BKM120 in vitro and in vivo. Interestingly, the sensitization mediated by HCQ could not be phenocopied by treatment with other autophagy inhibitors (Spautin-1, 3-MA and bafilomycin A1) or knockdown of the essential autophagy genes Atg5/Atg7, suggesting that the sensitizing effect might be mediated independent of autophagy status. Mechanistically, HCQ induced ROS production and activated the transcription factor NRF2. In contrast, BKM120 prevented the elimination of ROS by inactivation of NRF2, leading to accumulation of DNA damage. In addition, HCQ activated ATM to enhance HR repair, a high-fidelity repair for DNA double-strand breaks (DSBs) in cells, while BKM120 inhibited HR repair by blocking the phosphorylation of ATM and the expression of BRCA1/2 and Rad51. Conclusions: Our study revealed that HCQ and BKM120 synergistically increased DSBs in tumor cells and therefore augmented apoptosis, resulting in enhanced antitumor efficacy. Our findings provide a new insight into how HCQ exhibits antitumor efficacy and synergizes with PI3Ki BKM120, and warn that one should consider the “off target” effects of HCQ when used as autophagy inhibitor in the clinical treatment of cancer.


2020 ◽  
Vol 19 (10) ◽  
pp. 1619-1631
Author(s):  
Elez D. Vainer ◽  
Juliane Kania-Almog ◽  
Ghadeer Zatara ◽  
Yishai Levin ◽  
Gilad W. Vainer

Using a simple, environment friendly proteome extraction (TOP), we were able to optimize the analysis of clinical samples. Using our TOP method we analyzed a clinical cohort of microsatellite stable (MSS) and unstable (MSI-H) colorectal carcinoma (CRC). We identified a tumor cell specific, STAT1-centered, immune signature expressed by the MSI-H tumor cells. We then showed that long, but not short, exposure to Interferon-γ induces a similar signature in vitro. We identified 10 different temporal protein expression patterns, classifying the Interferon-γ protein temporal regulation in CRC. Our data sheds light on the changes that tumor cells undergo under long-term immunological pressure in vivo, the importance of STAT proteins in specific biological scenarios. The data generated could help find novel clinical biomarkers and therapeutic approaches.


2008 ◽  
Vol 7 (7) ◽  
pp. 1037-1043 ◽  
Author(s):  
Yu Shuyi ◽  
Duan Juping ◽  
Zhou Zhiqun ◽  
Pang Qiong ◽  
Ji Wuyang ◽  
...  

2016 ◽  
Vol 62 (2) ◽  
pp. 328-334 ◽  
Author(s):  
Klaus Pantel ◽  
Catherine Alix-Panabières

AbstractBACKGROUNDResearch on circulating tumor cells (CTCs) as new biomarkers has received great attention over the past decade. In particular, the capture and analysis of CTCs as “liquid biopsies” provides the possibility to avoid invasive tissue biopsies, with obvious implications in cancer diagnostics.CONTENTThe focus of this review is to describe and discuss how functional studies on viable CTCs can enlarge the spectrum of applications of liquid biopsies, with emphasis on breast, prostate, colon, and lung cancer as the major tumor entities in industrialized countries. The low number of CTCs in the peripheral blood of most cancer patients makes challenging the in vitro culture of CTCs. Epithelial tumor cells are difficult to culture, even when starting with millions of tumor cells. Recently, several groups have achieved important advances in the in vitro and in vivo expansion of CTCs from cancer patients at very advanced stages with higher amounts of CTCs. Here, we present current technologies to enrich and detect viable human CTCs, including positive and negative enrichment strategies that are based on antigen expression and physical properties of CTCs. We also discuss published data about functional studies on CTCs that use in vitro and in vivo models.SUMMARYFunctional analyses on CTCs offer the possibility to identify the biological properties of metastatic cells, including the identification of metastasis-initiating cells. Moreover, CTC-derived cell lines and xenografts might reveal new therapeutic targets and can be used for drug screening.


2021 ◽  
Vol 22 (17) ◽  
pp. 9279
Author(s):  
Inés Martínez-Pena ◽  
Pablo Hurtado ◽  
Nuria Carmona-Ule ◽  
Carmen Abuín ◽  
Ana Belén Dávila-Ibáñez ◽  
...  

Background: Cancer metastasis is a deathly process, and a better understanding of the different steps is needed. The shedding of circulating tumor cells (CTCs) and CTC-cluster from the primary tumor, its survival in circulation, and homing are key events of the metastasis cascade. In vitro models of CTCs and in vivo models of metastasis represent an excellent opportunity to delve into the behavior of metastatic cells, to gain understanding on how secondary tumors appear. Methods: Using the zebrafish embryo, in combination with the mouse and in vitro assays, as an in vivo model of the spatiotemporal development of metastases, we study the metastatic competency of breast cancer CTCs and CTC-clusters and the molecular mechanisms. Results: CTC-clusters disseminated at a lower frequency than single CTCs in the zebrafish and showed a reduced capacity to invade. A temporal follow-up of the behavior of disseminated CTCs showed a higher survival and proliferation capacity of CTC-clusters, supported by their increased resistance to fluid shear stress. These data were corroborated in mouse studies. In addition, a differential gene signature was observed, with CTC-clusters upregulating cell cycle and stemness related genes. Conclusions: The zebrafish embryo is a valuable model system to understand the biology of breast cancer CTCs and CTC-clusters.


2018 ◽  
Vol 115 (36) ◽  
pp. E8479-E8488 ◽  
Author(s):  
Michael J. Morgan ◽  
Brent E. Fitzwalter ◽  
Charles R. Owens ◽  
Rani K. Powers ◽  
Joseph L. Sottnik ◽  
...  

Molecular alterations that confer phenotypic advantages to tumors can also expose specific therapeutic vulnerabilities. To search for potential treatments that would selectively affect metastatic cells, we examined the sensitivity of lineage-related human bladder cancer cell lines with different lung colonization abilities to chloroquine (CQ) or bafilomycin A1, which are inhibitors of lysosome function and autophagy. Both CQ and bafilomycin A1 were more cytotoxic in vitro to highly metastatic cells compared with their less metastatic counterparts. Genetic inactivation of macroautophagy regulators and lysosomal proteins indicated that this was due to greater reliance on the lysosome but not upon macroautophagy. To identify the mechanism underlying these effects, we generated cells resistant to CQ in vitro. Surprisingly, selection for in vitro CQ resistance was sufficient to alter gene expression patterns such that unsupervised cluster analysis of whole-transcriptome data indicated that selection for CQ resistance alone created tumor cells that were more similar to the poorly metastatic parental cells from which the metastatic cells were derived; importantly, these tumor cells also had diminished metastatic ability in vivo. These effects were mediated in part by differential expression of the transcriptional regulator ID4 (inhibitor of DNA binding 4); depletion of ID4 both promoted in vitro CQ sensitivity and restored lung colonization and metastasis of CQ-resistant cells. These data demonstrate that selection for metastasis ability confers selective vulnerability to lysosomal inhibitors and identify ID4 as a potential biomarker for the use of lysosomal inhibitors to reduce metastasis in patients.


2016 ◽  
Author(s):  
Marina C. Cabrera ◽  
Elaine Hurt ◽  
Xiaoru Chen ◽  
Shi Xiaoqing ◽  
Haifeng Bao

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