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Suppression of MAPK Signaling and Reversal of mTOR-Dependent MDR1-Associated Multidrug Resistance by 21α-Methylmelianodiol in Lung Cancer Cells.

Aldonza MB, Hong JY, Bae SY, Song J, Kim WK, Oh J, Shin Y, Lee SH, Lee SK - PLoS ONE (2015)

Bottom Line: Interplay between PI3K/AMPK/AKT and MAPK pathways is a crucial effector in lung cancer growth and progression.Here, we described whether 21α-Methylmelianodiol (21α-MMD), an active triterpenoid derivative of Poncirus trifoliate, can display anticancer properties by regulating these signals and modulate the occurrence of multidrug resistance in NSCLC cells.Employing the established paclitaxel-resistant A549 cells (A549-PacR), we further found that 21α-MMD induced a MDR reversal activity through the inhibition of P-gp/MDR1 expressions, function, and transcription with regained paclitaxel sensitivity which might dependently correlate to the regulation of PI3K/mTOR signaling pathway.

View Article: PubMed Central - PubMed

Affiliation: College of Pharmacy, Seoul National University, Seoul, Korea.

ABSTRACT
Lung cancer is the leading cause of cancer-related deaths worldwide and remains the most prevalent. Interplay between PI3K/AMPK/AKT and MAPK pathways is a crucial effector in lung cancer growth and progression. These signals transduction protein kinases serve as good therapeutic targets for non-small cell lung cancer (NSCLC) which comprises up to 90% of lung cancers. Here, we described whether 21α-Methylmelianodiol (21α-MMD), an active triterpenoid derivative of Poncirus trifoliate, can display anticancer properties by regulating these signals and modulate the occurrence of multidrug resistance in NSCLC cells. We found that 21α-MMD inhibited the growth and colony formation of lung cancer cells without affecting the normal lung cell phenotype. 21α-MMD also abrogated the metastatic activity of lung cancer cells through the inhibition of cell migration and invasion, and induced G0/G1 cell cycle arrest with increased intracellular ROS generation and loss of mitochondrial membrane integrity. 21α-MMD regulated the expressions of PI3K/AKT/AMPK and MAPK signaling which drove us to further evaluate its activity on multidrug resistance (MDR) in lung cancer cells by specifying on P-glycoprotein (P-gp)/MDR1-association. Employing the established paclitaxel-resistant A549 cells (A549-PacR), we further found that 21α-MMD induced a MDR reversal activity through the inhibition of P-gp/MDR1 expressions, function, and transcription with regained paclitaxel sensitivity which might dependently correlate to the regulation of PI3K/mTOR signaling pathway. Taken together, these findings demonstrate, for the first time, the mechanistic evaluation in vitro of 21α-MMD displaying growth-inhibiting potential with influence on MDR reversal in human lung cancer cells.

No MeSH data available.


Related in: MedlinePlus

Intensification of paclitaxel and 5-FU cytotoxicity in A549 and A549-PacR cells by 21α-MMD.The cytotoxicity of 21α-MMD (6.25–100 μM), paclitaxel (12.5–200 μM), and 5-FU (2–60 μM) alone or in combination in A549 and A549-PacR cells was determined by MTT assay. Each point indicates the mean ± SD of three independent experiments, performed in triplicate. (A) Effects of 21α-MMD and paclitaxel (B) and 5-FU in A549 cells. (C) Effect of 21α-MMD (D) and paclitaxel (E) and 5-FU in A549-PacR cells. Cells were pretreated with or without 21α-MMD followed by various concentrations of paclitaxel or 5-FU for 24 h. MTT data were presented as the surviving cell viability after treatment regime. A negative control was used which identifies as the respective drug used in combination with 21α-MMD.
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pone.0127841.g005: Intensification of paclitaxel and 5-FU cytotoxicity in A549 and A549-PacR cells by 21α-MMD.The cytotoxicity of 21α-MMD (6.25–100 μM), paclitaxel (12.5–200 μM), and 5-FU (2–60 μM) alone or in combination in A549 and A549-PacR cells was determined by MTT assay. Each point indicates the mean ± SD of three independent experiments, performed in triplicate. (A) Effects of 21α-MMD and paclitaxel (B) and 5-FU in A549 cells. (C) Effect of 21α-MMD (D) and paclitaxel (E) and 5-FU in A549-PacR cells. Cells were pretreated with or without 21α-MMD followed by various concentrations of paclitaxel or 5-FU for 24 h. MTT data were presented as the surviving cell viability after treatment regime. A negative control was used which identifies as the respective drug used in combination with 21α-MMD.

Mentions: We further examined the effect of 21α-MMD in combination paclitaxel and 5-FU, currently used in the clinic for lung cancer treatment, on lung cancer cell growth at 24 h. To search for the optimal concentrations, various concentrations of drugs were tested based on their IC50 values. Parental A549 and MDR phenotype A549-PacR cells were used as models to identify whether 21α-MMD can synergize with paclitaxel to either or both produce an effective combination strategy and overcome paclitaxel-resistance. In addition, 5-FU was also employed since it was observed that A549-PacR has a cross-resistance to this drug in the preliminary findings of this experiment. The viability of the cells were examined by MTT assay, which suggested that the concentration groups of 21α-MMD used in this study (6.25 to 100 μM) showed a significant potentiating inhibitory effect to the cell viability of A549 (Fig 5A and 5B) when combined with paclitaxel and 5-FU, respectively. The paclitaxel and 5-FU treatments individually were used as negative controls. The interaction between 21α-MMD and paclitaxel or 5-FU was further evaluated by combination index (CI) analysis. The CI analysis for combining 21α-MMD with cytotoxic agents revealed significant synergy in A549 cells (Table 2). There is a clear synergistic effect in all combinations tested in A549 cells, although with different degree variations from slight to strong synergism with CI values of less than 1, producing a concentration-dependent decrease in the IC50 values of paclitaxel and 5-FU in A549 cells. These findings suggest that 21α-MMD might be a potential agent for combination therapy in the clinic. In the context of MDR reversal, 21α-MMD alone significantly inhibited the growth of A549-PacR in a concentration-dependent manner for 24 h (Fig 5C), suggesting a potential MDR modulatory activity. In A549-PacR cells, 21α-MMD significantly sensitized the MDR cells to either paclitaxel or 5-FU with observed dramatic inhibitory shift after treatment in a concentration-dependent manner for 24 h (Fig 5D and 5E). These results demonstrate that 21α-MMD significantly sensitizes P-gp/MDR1-overexpressing A549-PacR cells to anti-cancer agents that are ABCB1 substrates.


Suppression of MAPK Signaling and Reversal of mTOR-Dependent MDR1-Associated Multidrug Resistance by 21α-Methylmelianodiol in Lung Cancer Cells.

Aldonza MB, Hong JY, Bae SY, Song J, Kim WK, Oh J, Shin Y, Lee SH, Lee SK - PLoS ONE (2015)

Intensification of paclitaxel and 5-FU cytotoxicity in A549 and A549-PacR cells by 21α-MMD.The cytotoxicity of 21α-MMD (6.25–100 μM), paclitaxel (12.5–200 μM), and 5-FU (2–60 μM) alone or in combination in A549 and A549-PacR cells was determined by MTT assay. Each point indicates the mean ± SD of three independent experiments, performed in triplicate. (A) Effects of 21α-MMD and paclitaxel (B) and 5-FU in A549 cells. (C) Effect of 21α-MMD (D) and paclitaxel (E) and 5-FU in A549-PacR cells. Cells were pretreated with or without 21α-MMD followed by various concentrations of paclitaxel or 5-FU for 24 h. MTT data were presented as the surviving cell viability after treatment regime. A negative control was used which identifies as the respective drug used in combination with 21α-MMD.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4476707&req=5

pone.0127841.g005: Intensification of paclitaxel and 5-FU cytotoxicity in A549 and A549-PacR cells by 21α-MMD.The cytotoxicity of 21α-MMD (6.25–100 μM), paclitaxel (12.5–200 μM), and 5-FU (2–60 μM) alone or in combination in A549 and A549-PacR cells was determined by MTT assay. Each point indicates the mean ± SD of three independent experiments, performed in triplicate. (A) Effects of 21α-MMD and paclitaxel (B) and 5-FU in A549 cells. (C) Effect of 21α-MMD (D) and paclitaxel (E) and 5-FU in A549-PacR cells. Cells were pretreated with or without 21α-MMD followed by various concentrations of paclitaxel or 5-FU for 24 h. MTT data were presented as the surviving cell viability after treatment regime. A negative control was used which identifies as the respective drug used in combination with 21α-MMD.
Mentions: We further examined the effect of 21α-MMD in combination paclitaxel and 5-FU, currently used in the clinic for lung cancer treatment, on lung cancer cell growth at 24 h. To search for the optimal concentrations, various concentrations of drugs were tested based on their IC50 values. Parental A549 and MDR phenotype A549-PacR cells were used as models to identify whether 21α-MMD can synergize with paclitaxel to either or both produce an effective combination strategy and overcome paclitaxel-resistance. In addition, 5-FU was also employed since it was observed that A549-PacR has a cross-resistance to this drug in the preliminary findings of this experiment. The viability of the cells were examined by MTT assay, which suggested that the concentration groups of 21α-MMD used in this study (6.25 to 100 μM) showed a significant potentiating inhibitory effect to the cell viability of A549 (Fig 5A and 5B) when combined with paclitaxel and 5-FU, respectively. The paclitaxel and 5-FU treatments individually were used as negative controls. The interaction between 21α-MMD and paclitaxel or 5-FU was further evaluated by combination index (CI) analysis. The CI analysis for combining 21α-MMD with cytotoxic agents revealed significant synergy in A549 cells (Table 2). There is a clear synergistic effect in all combinations tested in A549 cells, although with different degree variations from slight to strong synergism with CI values of less than 1, producing a concentration-dependent decrease in the IC50 values of paclitaxel and 5-FU in A549 cells. These findings suggest that 21α-MMD might be a potential agent for combination therapy in the clinic. In the context of MDR reversal, 21α-MMD alone significantly inhibited the growth of A549-PacR in a concentration-dependent manner for 24 h (Fig 5C), suggesting a potential MDR modulatory activity. In A549-PacR cells, 21α-MMD significantly sensitized the MDR cells to either paclitaxel or 5-FU with observed dramatic inhibitory shift after treatment in a concentration-dependent manner for 24 h (Fig 5D and 5E). These results demonstrate that 21α-MMD significantly sensitizes P-gp/MDR1-overexpressing A549-PacR cells to anti-cancer agents that are ABCB1 substrates.

Bottom Line: Interplay between PI3K/AMPK/AKT and MAPK pathways is a crucial effector in lung cancer growth and progression.Here, we described whether 21α-Methylmelianodiol (21α-MMD), an active triterpenoid derivative of Poncirus trifoliate, can display anticancer properties by regulating these signals and modulate the occurrence of multidrug resistance in NSCLC cells.Employing the established paclitaxel-resistant A549 cells (A549-PacR), we further found that 21α-MMD induced a MDR reversal activity through the inhibition of P-gp/MDR1 expressions, function, and transcription with regained paclitaxel sensitivity which might dependently correlate to the regulation of PI3K/mTOR signaling pathway.

View Article: PubMed Central - PubMed

Affiliation: College of Pharmacy, Seoul National University, Seoul, Korea.

ABSTRACT
Lung cancer is the leading cause of cancer-related deaths worldwide and remains the most prevalent. Interplay between PI3K/AMPK/AKT and MAPK pathways is a crucial effector in lung cancer growth and progression. These signals transduction protein kinases serve as good therapeutic targets for non-small cell lung cancer (NSCLC) which comprises up to 90% of lung cancers. Here, we described whether 21α-Methylmelianodiol (21α-MMD), an active triterpenoid derivative of Poncirus trifoliate, can display anticancer properties by regulating these signals and modulate the occurrence of multidrug resistance in NSCLC cells. We found that 21α-MMD inhibited the growth and colony formation of lung cancer cells without affecting the normal lung cell phenotype. 21α-MMD also abrogated the metastatic activity of lung cancer cells through the inhibition of cell migration and invasion, and induced G0/G1 cell cycle arrest with increased intracellular ROS generation and loss of mitochondrial membrane integrity. 21α-MMD regulated the expressions of PI3K/AKT/AMPK and MAPK signaling which drove us to further evaluate its activity on multidrug resistance (MDR) in lung cancer cells by specifying on P-glycoprotein (P-gp)/MDR1-association. Employing the established paclitaxel-resistant A549 cells (A549-PacR), we further found that 21α-MMD induced a MDR reversal activity through the inhibition of P-gp/MDR1 expressions, function, and transcription with regained paclitaxel sensitivity which might dependently correlate to the regulation of PI3K/mTOR signaling pathway. Taken together, these findings demonstrate, for the first time, the mechanistic evaluation in vitro of 21α-MMD displaying growth-inhibiting potential with influence on MDR reversal in human lung cancer cells.

No MeSH data available.


Related in: MedlinePlus