scholarly journals Drug resistance occurred in a newly characterized preclinical model of lung cancer brain metastasis.

2020 ◽  
Author(s):  
Neal Shah ◽  
Zhongwei Liu ◽  
Rachel M. Tallman ◽  
Afroz Mohammad ◽  
Samuel A Sprowls ◽  
...  

Abstract Background Cancer metastasis and drug resistance have traditionally been studied separately, though these two lethal pathological phenomena almost always occur concurrently. Brain metastasis occurs in a large proportion of lung cancer patients (~30%). Once diagnosed, patients have a poor prognosis surviving typically less than 1 year due to lack of treatment efficacy. Methods Human metastatic lung cancer cells (PC-9-Br) were injected into the left cardiac ventricle of female athymic nude mice. Brain lesions were allowed to grow for 21 days, animals were then randomized into treatment groups and treated until presentation of neurological symptoms or when moribund. Prior to tissue collection mice were injected with Oregon Green and 14C-Aminoisobutyric acid followed by an indocyanine green vascular washout. Tracer accumulation was determined by quantitative fluorescent microscopy and quantitative autoradiography. Survival was tracked and tumor burden was monitored via bioluminescent imaging. Extent of mutation differences and acquired resistance was measured in-vitro through half-maximal inhibitory assays and qRT-PCR analysis. Results A PC-9 brain seeking line (PC-9-Br) was established. Mice inoculated with PC-9-Br resulted in a significantly decreased survival time compared with mice inoculated with parental PC-9. Non-targeted chemotherapy with cisplatin and etoposide (51.5 days) significantly prolonged survival of PC-9-Br brain metastases in mice compared to vehicle control (42 days) or cisplatin and pemetrexed (45 days). Further in-vivo imaging showed greater tumor vasculature in mice treated with cisplatin and etoposide compared to non-tumor regions, which was not observed in mice treated with vehicle or cisplatin and pemetrexed. More importantly, PC-9-Br showed significant resistance to gefitinib by in-vitro MTT assays (IC50>2.5 µM at 48hrs and 0.1 µM at 72hrs) compared with parental PC-9 (IC50: 0.75 µM at 48hrs and 0.027 µM at 72hrs). Further studies on the molecular mechanisms of gefitinib resistance revealed that EGFR and phospho-EGFR were significantly decreased in PC-9-Br compared with PC-9. Expression of E-cadherin and vimentin did not show EMT in PC-9-Br compared with parental PC-9, and PC-9-Br had neither T790 mutation nor amplifications of MET and HER2 compared with parental PC-9. Conclusion Our study demonstrated that brain metastases of lung cancer cells may independently prompt drug resistance without drug treatment.

2020 ◽  
Author(s):  
Neal Shah ◽  
Zhongwei Liu ◽  
Rachel M. Tallman ◽  
Afroz Mohammad ◽  
Samuel A Sprowls ◽  
...  

Abstract Background Cancer metastasis and drug resistance have traditionally been studied separately, though these two lethal pathological phenomena almost always occur concurrently. Brain metastasis occurs in a large proportion of lung cancer patients (~30%). Once diagnosed, patients have a poor prognosis surviving typically less than 1 year due to lack of treatment efficacy. Methods Human metastatic lung cancer cells (PC-9-Br) were injected into the left cardiac ventricle of female athymic nude mice. Brain lesions were allowed to grow for 21 days, animals were then randomized into treatment groups and treated until presentation of neurological symptoms or when moribund. Prior to tissue collection mice were injected with Oregon Green and 14C-Aminoisobutyric acid followed by an indocyanine green vascular washout. Tracer accumulation was determined by quantitative fluorescent microscopy and quantitative autoradiography. Survival was tracked and tumor burden was monitored via bioluminescent imaging. Extent of mutation differences and acquired resistance was measured in-vitro through half-maximal inhibitory assays and qRT-PCR analysis. Results A PC-9 brain seeking line (PC-9-Br) was established. Mice inoculated with PC-9-Br resulted in a significantly decreased survival time compared with mice inoculated with parental PC-9. Non-targeted chemotherapy with cisplatin and etoposide (51.5 days) significantly prolonged survival of PC-9-Br brain metastases in mice compared to vehicle control (42 days) or cisplatin and pemetrexed (45 days). Further in-vivo imaging showed greater tumor vasculature in mice treated with cisplatin and etoposide compared to non-tumor regions, which was not observed in mice treated with vehicle or cisplatin and pemetrexed. More importantly, PC-9-Br showed significant resistance to gefitinib by in-vitro MTT assays (IC50>2.5 µM at 48hrs and 0.1 µM at 72hrs) compared with parental PC-9 (IC50: 0.75 µM at 48hrs and 0.027 µM at 72hrs). Further studies on the molecular mechanisms of gefitinib resistance revealed that EGFR and phospho-EGFR were significantly decreased in PC-9-Br compared with PC-9. Expression of E-cadherin and vimentin did not show EMT in PC-9-Br compared with parental PC-9, and PC-9-Br had neither T790 mutation nor amplifications of MET and HER2 compared with parental PC-9. Conclusion Our study demonstrated that brain metastases of lung cancer cells may independently prompt drug resistance without drug treatment.


2019 ◽  
Author(s):  
Neal Shah ◽  
Zhongwei Liu ◽  
Rachel M. Tallman ◽  
Afroz Mohammad ◽  
Samuel A Sprowls ◽  
...  

Abstract Background Cancer metastasis and drug resistance have traditionally been studied separately, though these two lethal pathological phenomena almost always occur concurrently. Brain metastasis occurs in a large proportion of lung cancer patients (~30%). Once diagnosed, patients have a poor prognosis surviving typically less than 1 year due to lack of treatment efficacy. Methods Human metastatic lung cancer cells (PC-9-Br) were injected into the left cardiac ventricle of female athymic nude mice. Brain lesions were allowed to grow for 21 days, animals were then randomized into treatment groups and treated until presentation of neurological symptoms or when moribund. Prior to tissue collection mice were injected with Oregon Green and 14C-Aminoisobutyric acid followed by an indocyanine green vascular washout. Tracer accumulation was determined by quantitative fluorescent microscopy and quantitative autoradiography. Survival was tracked and tumor burden was monitored via bioluminescent imaging. Extent of mutation differences and acquired resistance was measured in-vitro through half-maximal inhibitory assays and qRT-PCR analysis. Results A PC-9 brain seeking line (PC-9-Br) was established. Mice inoculated with PC-9-Br resulted in a significantly decreased survival time compared with mice inoculated with parental PC-9. Non-targeted chemotherapy with cisplatin and etoposide (51.5 days) significantly prolonged survival of PC-9-Br brain metastases in mice compared to vehicle control (42 days) or cisplatin and pemetrexed (45 days). Further in-vivo imaging showed greater tumor vasculature in mice treated with cisplatin and etoposide compared to non-tumor regions, which was not observed in mice treated with vehicle or cisplatin and pemetrexed. More importantly, PC-9-Br showed significant resistance to gefitinib by in-vitro MTT assays (IC50>2.5 µM at 48hrs and 0.1 µM at 72hrs) compared with parental PC-9 (IC50: 0.75 µM at 48hrs and 0.027 µM at 72hrs). Further studies on the molecular mechanisms of gefitinib resistance revealed that EGFR and phospho-EGFR were significantly decreased in PC-9-Br compared with PC-9. Expression of E-cadherin and vimentin did not show EMT in PC-9-Br compared with parental PC-9, and PC-9-Br had neither T790 mutation nor amplifications of MET and HER2 compared with parental PC-9. Conclusion Our study demonstrated that brain metastases of lung cancer cells may independently prompt drug resistance without drug treatment.


2021 ◽  
pp. 1-9
Author(s):  
Huan Guo ◽  
Baozhen Zeng ◽  
Liqiong Wang ◽  
Chunlei Ge ◽  
Xianglin Zuo ◽  
...  

BACKGROUND: The incidence of lung cancer in Yunnan area ranks firstly in the world and underlying molecular mechanisms of lung cancer in Yunnan region are still unclear. We screened a novel potential oncogene CYP2S1 used mRNA microassay and bioinformation database. The function of CYP2S1 in lung cancer has not been reported. OBJECTIVE: To investigate the functions of CYP2S1 in lung cancer. METHODS: Immunohistochemistry and Real-time PCR were used to verify the expression of CYP2S1. Colony formation and Transwell assays were used to determine cell proliferation, invasion and migration. Xenograft assays were used to detected cell growth in vivo. RESULTS: CYP2S1 is significantly up-regulated in lung cancer tissues and cells. Knockdown CYP2S1 in lung cancer cells resulted in decrease cell proliferation, invasion and migration in vitro. Animal experiments showed downregulation of CYP2S1 inhibited lung cancer cell growth in vivo. GSEA analysis suggested that CYP2S1 played functions by regulating E2F targets and G2M checkpoint pathway which involved in cell cycle. Kaplan-Meier analysis indicated that patients with high CYP2S1 had markedly shorter event overall survival (OS) time. CONCLUSIONS: Our data demonstrate that CYP2S1 exerts tumor suppressor function in lung cancer. The high expression of CYP2S1 is an unfavorable prognostic marker for patient survival.


2020 ◽  
Vol 38 (15_suppl) ◽  
pp. 3597-3597
Author(s):  
Haiying Cheng ◽  
Ni Fan ◽  
Ethan Sokol ◽  
Feng Wang ◽  
Yiyu Zou ◽  
...  

3597 Background: Approximately 20% to 50% of patients with advanced lung cancer develop brain metastases, which are associated with debilitating neurologic impairment and a dismal prognosis. There have been very limited studies investigating the genomics of brain metastases in lung cancer. Methods: We comprehensively investigated the frequency of PI3K/AKT/RICTOR/mTOR pathway aberrations in primary and metastatic sites using an extensive database of 11845 cases of lung adenocarcinoma by NGS (FoundationOne). The potential roles of RICTOR amplification in the development of brain metastases were studied both in vitro and in vivo in orthotopic mouse models. Results: Compared to the primary tumor, PI3K/AKT/mTOR gene alterations were more frequent in metastatic sites, with particular enrichment noted in brain metastases. RICTOR amplification alone accounted for the observed higher frequency both in brain metastases (brain vs. primary: 9.73% vs 3.50%, P = 2.6E-14; brain vs. other mets: 9.73% vs. 7.3%, P = 0.03) and other metastatic sites (other mets vs. primary: 7.3% vs.3.5%, P = 10E-15), whereas the frequency of PTEN, AKT1, PK3CA or mTOR genetic alterations was not different in the primary tumor, brain and other metastatic sites. In vitro, inducible RICTOR knockdown in H23 lung cancer cells (parental line with RICTOR amplification) was associated with reduced cell migration and invasion, whereas upregulation of RICTOR in HCC827 lung cancer cells (parental line with normal RICTOR copy numbers) was associated with an increase of both processes. These results were confirmed with pharmacological inhibition using mTOR1/2 inhibitors with known CNS penetration. In vivo, both inducible ablation of RICTOR and the mTOR1/2 inhibitor TAK228 (Sapanisertinib) significantly inhibited lung cancer H23-R4-Luc tumor growth in the brain, including a number of near complete responses. Mechanistic studies suggest that RICTOR may regulate the brain metastasis process through AKT and CXCL12 chemokine-CXCR4 axis. Conclusions: RICTOR amplification is the first identified actionable target that is markedly enriched in brain metastases. Our study provides a strong rationale for the development of RICTOR-targeted therapeutic strategies for the treatment and/or prevention of these major causes of lung cancer morbidity and mortality.


2021 ◽  
Author(s):  
Roni F Rayes ◽  
Marnie G Wilson ◽  
Stephen D Gowing ◽  
France Bourdeau ◽  
Betty Giannias ◽  
...  

Background: Lung cancer is a leading cause of death partially due to high recurrence rates after surgical resection. Clinical data suggest that post-operative infections may increase the risk of recurrence. Our previous work indicated that increased adhesion of circulating tumors in the context of infection is partially responsible for this phenotype. However, cancer metastasis is a multi-step process, and it is likely that other events following tumor adhesion also play a role. Methods: In vivo intrasplenic injection of murine lung cancer cells into wild type (WT) and Toll-like receptor 4 knockout (TLR4-/-) mice followed by cecal-ligation and puncture (CLP) as a model of post-operative infection or sham surgery were used. H&E staining and immunohistochemistry analysis of Ki67+ cells in the livers of those mice were performed. In vitro proliferation assays were performed on human lung cancer cells using combinations of TLR blockade. Results: We found a 5-fold increase in hepatic metastases in WT CLP mice compared to WT sham mice. TLR4-/- CLP mice had a significant decreased tumor burden compared to WT CLP mice. This indicated an important mechanistic role for the TLR4-initiated host response to gram negative infection post-tumor cell adhesion. By analyzing the livers of those mice, we observed an increase in proliferation of tumor micrometastases in vivo in WT CLP mice as compared to WT sham mice. Here again, CLP TLR4 -/- mice had significantly fewer replicating micrometastases than CLP WT mice. Indeed, we found that direct stimulation of lung cancer cells with heat-inactivated E.Coli resulted in increased proliferation of tumor growth in vitro. These effects were partially abrogated by tumor TLR4 blockade; combined TLR2, 4 and 5 blockades led to a more prominent decrease. Conditioned media from bronchoalveolar epithelial cells treated with lipopolysaccharide lead to increased lung cancer proliferation; these changes were reversed with TLR blockade, indicating that the host response to infection is TLR mediated. Conclusions: Overall, these results imply a more complex mechanistic role of post-operative infection in metastasis. From a clinical standpoint, this evidence strengthens the case for the use of TLR blockade as a potential therapeutic target in the prevention of metastasis.


Cancers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 4057
Author(s):  
Yen-Yun Wang ◽  
Anupama Vadhan ◽  
Ping-Ho Chen ◽  
Yen-Lung Lee ◽  
Chih-Yeh Chao ◽  
...  

Lung cancer is a malignancy with high mortality worldwide, and metastasis occurs at a high frequency even when cancer spread is not detectable at primary operation. Cancer stemness plays an important role in malignant cancer behavior, treatment resistance, and cancer metastasis. Therefore, understanding the molecular pathogenesis behind cancer-stemness-mediated metastasis and developing effective approaches to prevent metastasis are key issues for improving cancer treatment. In this study, we investigated the role of CD44 stemness marker in lung cancer using in vitro and clinical studies. Immunohistochemical staining of lung cancer tissue specimens revealed that primary tumors with higher CD44 expression showed increased metastasis to regional lymph nodes. Flow cytometry analysis suggested that CD44 positive cells were enriched in the metastatic lymph nodes compared to the primary tumors. CD44 overexpression significantly increased migration and invasion abilities of lung cancer cells through CD44-induced ERK phosphorylation, ZEB1 upregulation, and Claudin-1 downregulation. Furthermore, ERK inhibition suppressed the migration and invasion abilities of CD44-overexpressing lung cancer cells. In summary, our in vitro and clinical results indicate that CD44 may be a potential prognostic and therapeutic marker for lung cancer patients.


2021 ◽  
Vol 10 ◽  
Author(s):  
Wu-Ping Zheng ◽  
Feng-Ying Huang ◽  
Shu-Zhen Dai ◽  
Jin-Yan Wang ◽  
Ying-Ying Lin ◽  
...  

Toxicarioside O (TCO), a natural product derived from Antiaris toxicaria, has been identified to be a promising anticancer agent. In this study, we aimed to investigate the effect of TCO on the proliferation and epithelial-mesenchymal transition (EMT) of lung cancer cells and its molecular mechanisms. Here, we indicated that TCO inhibits the proliferation of lung cancer cells both in vitro and in vivo. Our results demonstrated that TCO induces apoptosis in lung cancer cells. Moreover, we found that TCO suppresses EMT program and inhibits cell migration in vitro. Mechanistically, TCO decreases the expression of trophoblast cell surface antigen 2 (Trop2), resulting in inhibition of the PI3K/Akt pathway and EMT program. Overexpression of Trop2 rescues TCO-induced inhibition of cell proliferation and EMT. Our findings demonstrate that TCO markedly inhibits cell proliferation and EMT in lung cancer cells and provides guidance for its drug development.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Dongjie Ma ◽  
Yingzhi Qin ◽  
Shanqing Li ◽  
Li Li ◽  
Jia He ◽  
...  

Objective. To investigate the effects of circDENND4C on the malignant biological behavior of lung cancer and its downstream target genes and molecular mechanisms. Methods. The expression of circDENND4C in lung cancer tissues and cells was detected. After transfection with silenced circDENND4C, the expression levels of circDENND4C, miR-141-3p, and BRD4 in lung cancer cells were detected by qRT-PCR. The targeting relationship between circDENND4C and miR-141-3p as well as miR-141-3p and BRD4 was verified. Cell activity was detected by CCK-8 and EdU assay. Transwell assay was used to detect the invasiveness of A549 and NCI-H1299 in each group. Effects of circDENND4C on proliferation and metastasis of lung cancer in nude mice were studied. Results. In vitro and in vivo results showed that circDENND4C silencing reduced the proliferation, invasion, and metastasis of lung cancer cells. Mechanism studies showed that circDENND4C has a targeting relationship with miR-141-3p. However, miR-141-3p has a targeting relationship with BRD4. circDENND4C indirectly upregulated BRD4 through sponge adsorption of miR-141-3p, thereby promoting metastasis and proliferation of NSCLC. Conclusion. circDENND4C, as an oncogene, promotes the proliferation, invasion, and metastasis of lung cancer cells.


Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 638
Author(s):  
Kittipong Sanookpan ◽  
Nongyao Nonpanya ◽  
Boonchoo Sritularak ◽  
Pithi Chanvorachote

Cancer metastasis is the major cause of about 90% of cancer deaths. As epithelial-to-mesenchymal transition (EMT) is known for potentiating metastasis, this study aimed to elucidate the effect of ovalitenone on the suppression of EMT and metastasis-related behaviors, including cell movement and growth under detached conditions, and cancer stem cells (CSCs), of lung cancer cells. Methods: Cell viability and cell proliferation were determined by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazo-liumbromide (MTT) and colony formation assays. Cell migration and invasion were analyzed using a wound-healing assay and Boyden chamber assay, respectively. Anchorage-independent cell growth was determined. Cell protrusions (filopodia) were detected by phalloidin-rhodamine staining. Cancer stem cell phenotypes were assessed by spheroid formation. The proteins involved in cell migration and EMT were evaluated by Western blot analysis and immunofluorescence staining. Results: Ovalitenone was used at concentrations of 0–200 μM. While it caused no cytotoxic effects on lung cancer H460 and A549 cells, ovalitenone significantly suppressed anchorage-independent growth, CSC-like phenotypes, colony formation, and the ability of the cancer to migrate and invade cells. The anti-migration activity was confirmed by the reduction of filopodia in the cells treated with ovalitenone. Interestingly, we found that ovalitenone could significantly decrease the levels of N-cadherin, snail, and slug, while it increased E-cadherin, indicating EMT suppression. Additionally, the regulatory signaling of focal adhesion kinase (FAK), ATP-dependent tyrosine kinase (AKT), the mammalian target of rapamycin (mTOR), and cell division cycle 42 (Cdc42) was suppressed by ovalitenone. Conclusions: The results suggest that ovalitenone suppresses EMT via suppression of the AKT/mTOR signaling pathway. In addition, ovalitenone exhibited potential for the suppression of CSC phenotypes. These data reveal the anti-metastasis potential of the compound and support the development of ovalitenone treatment for lung cancer therapy.


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