Generation and characterization of MEK and ERK inhibitors- resistant non-small-cells-lung-cancer (NSCLC) cells

Abstract

BackgroundThe RAS/RAF/MEK/ERK pathway is one of the most downregulated pathway in cancer. Inhibitors of RAF and MEK have established clinical use while ERK inhibitors recently faced the clinic. We aimed to generate resistant cell lines which could be helpful for defining new combinations able to overcome resistance.Methodsthe human NSCLC cell line NCI-H727, sensitive to both MEK and ERK inhibitors, was treated with increasing concentrations of MEK162 (as MEK inhibitor) or SCH772984 as ERK inhibitor.Resultswe successfully obtained a MEK resistant subline (H727/MEK, after 40 passages) as well as an ERK resistant subline (H727/SCH, after 18 passages). The two resistant sublines H727/MEK and H727/SCH were cross-resistant to ERK and MEK inhibitors, respectively, but not to RAF inhibitors. The sublines maintained the responsiveness to inhibitors of the parallel PI3K/akt/mTOR pathway as well as to agents with different mechanism of action. Mechanistically, treatment of sensitive and resistant cells with MEK or ERK inhibitors was able to induce a similar inhibition of ERK phosphorylation, while only in parental cells the drugs were able to induce a downregulation of S6 and RSK phosphorylation.Conclusionsthese resistant cells represent an important tool for further studies on the mechanisms of resistance and ways to overcome it.

Hydroxysafflor yellow A inhibited lipopolysaccharide‐induced non‐small cell lung cancer cell proliferation, migration, and invasion by suppressing the PI3K/AKT/mTOR and ERK/MAPK signaling pathways

“…To further verify the involvement of PI3K/Akt/mTOR and ERK/MAPK signaling pathways in inhibiting proliferation and inducing apoptosis of A549 and H1299 cells induced by LPS, PI3K (LY294002) and ERK (SCH772984) inhibitors were employed to inhibit the PI3K/Akt/mTOR and ERK/MAPK signaling pathways related to proteins, respectively. 38,39 As expected, LY294002 and SCH772984 inhibited colony formation and promoted cell apoptosis of LPS-induced A549 and H1299 cells. Furthermore, co-treatment of HYSA and LY294002 or SCH772984 was superior for reducing colony formation and promoting apoptosis compared to either agent alone in LPS-induced A549 and H1299 cells (Fig 7).…”

“…The results of our study have demonstrated that the levels of PI3K/Akt/mTOR and ERK/MAPK signaling pathways related to proteins in A549 and H1299 cells induced by LPS are significantly suppressed after treatment with HYSA (5, 10, and 20 μM). To further verify the involvement of PI3K/Akt/mTOR and ERK/MAPK signaling pathways in inhibiting proliferation and inducing apoptosis of A549 and H1299 cells induced by LPS, PI3K (LY294002) and ERK (SCH772984) inhibitors were employed to inhibit the PI3K/Akt/mTOR and ERK/MAPK signaling pathways related to proteins, respectively . As expected, LY294002 and SCH772984 inhibited colony formation and promoted cell apoptosis of LPS‐induced A549 and H1299 cells.…”

“…In this study, the data showed that HYSA could significantly suppress the expression of the ERK/MAPK signaling pathway related to proteins in A549 and H1299 cells induced by LPS. To further confirm the HYSA exhibited positive activities on the development and progress of LPS‐induced A549 and H1299 cells through the signaling pathways, we used PI3K (LY294002) and ERK (SCH772984) inhibitors to inhibit the PI3K/Akt/mTOR and ERK/MAPK signaling pathways, respectively, and the data showed that LY294002 and SCH772984 inhibited the proliferation, reduced colony formation, promoted apoptosis, inhibited migration and invasion, suppressed vimentin and N‐cadherin expression, and promoted the protein expression of E‐cadherin in A549 and H1299 cells induced by LPS. Further, co‐treatment of HYSA and LY294002 or SCH772984 had superior effects than treatment with either one alone.…”

Integrin beta 4 (ITGB4) and its tyrosine-1510 phosphorylation promote pancreatic tumorigenesis and regulate the MEK1-ERK1/2 signaling pathway

“…The MAPK/MEK/ERK signaling pathway regulates gene expression, cell proliferation, differentiation, and apoptosis [17,18]. In pancreatic cancer patients, RAS mutations occur in 70-90% patients [19], which results in an abnormal activation of mitogen-activated protein kinase kinase (MEK)1 and MEK2, and subsequent hyperproliferation of pancreatic cancer cells.…”

Microarray Identifies a Key Carcinogenic Circular RNA 0008594 That Is Related to Non-Small-Cell Lung Cancer Development and Lymph Node Metastasis and Promotes NSCLC Progression by Regulating the miR-760-Mediated PI3K/AKT and MEK/ERK Pathways

“…Notably, miR-760 knockdown also attenuated the effect of circ_0008594 knockdown on NSCLC cell functions (all P<0.05, Figures 5A-I). MiR-760 is observed to regulate cancer progression via PI3K/ AKT and MEK/ERK pathways (25,27,28), and the latter pathways are closely implicated in NSCLC progression and stemness (29)(30)(31)(32); thus, we further detected the PI3K/AKT and MEK/ERK pathways, which found that circ_0008594 knockdown inactivated the PI3K/AKT and MEK/ERK pathways in both H23 and H460 cells, while miR-760 knockdown showed the opposite effect (all P<0.05, Figures 6A-D). Furthermore, miR-760 knockdown weakened the effect of circ_0008594 knockdown on regulating the PI3K/ AKT and MEK/ERK pathways in H23 and H460 cells (all P<0.05).…”