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[Down-regulated βIII-tubulin expression can reverse paclitaxel resistance in A549/taxol cells lines]
1Department of Internal Medicine, Shandong Province Hospital of Occupational Diseases, Jinan 250002, China.
Background:
Chemotherapy drug resistance is the primary causes of death in patients with pulmonary carcinoma which make tumor recurrence or metastasis. β-tubulin is the main cell targets of anti-microtubule drug. Increased expression of βIII-tubulin has been implicated in non-small cell lung cancer (NSCLC) cell lines. To explore the relationship among the expression level of βIII-tubulin and the sensitivity of A549/Taxolcell lines to Taxol and cell cycles and cell apoptosis by RNA interference-mediated inhibition of βIII-tubulin in A549/Taxol cells.
Methods:
Three pairs of siRNA targetd βIII-tubulin were designed and prepared, which were transfected into A549/Taxol cells using LipofectamineTM 2000. We detected the expression of βIII-tubulin mRNA using Real-time fluorescence qRT-PCR. Tedhen we selected the most efficient siRNA by the expression of βIII-tubulin mRNA in transfected group. βIII-tubulin protein level were mesured by Western blot. The taxol sensitivity in transfected group were evaluated by MTT assay. And the cell apoptosis and cell cycles were determined by flow cytometry.
Results:
βIII-tubulin mRNA levels in A549/Taxol cells were significantly decreased in transfected grop by Real-time qRT-PCR than control groups. And βIII-tubulin siRNA-1 sequence showed the highest transfection efficiency, which was (87.73±4.87)% (P<0.01); Western blot results showed that the expressional level of BIII tublin protein was significantly down-reulated in the transfectant cells than thant in the control cells. By MTT assay, we showed that the inhibition ratio of Taxol to A549/Taxol cells transfeced was higher than that of control group (51.77±4.60)% (P<0.01). The early apoptosis rate of A549/Taxol cells in transfected group were significantly higher than that of control group (P<0.01); G2-M content in taxol group obviously increased than untreated samples by the cell cycle (P<0.05).
Conclusions:
βIII-tubulin down-regulated significantly sensitized NSCLC A549/Taxol cells to Paclitaxel.
Insights
Inhibiting βIII-tubulin in non-small cell lung cancer (NSCLC) cells increases their sensitivity to chemotherapy drugs like Paclitaxel. This finding offers a potential strategy to overcome drug resistance in lung cancer treatment.
Area of Science:
- Molecular Biology
- Oncology
- Pharmacology
Context:
- Chemotherapy resistance is a major cause of mortality in pulmonary carcinoma, often leading to tumor recurrence and metastasis.
- β-tubulin, particularly βIII-tubulin, is a key cellular target for anti-microtubule chemotherapy drugs.
- Elevated βIII-tubulin expression is linked to chemoresistance in non-small cell lung cancer (NSCLC) cell lines.
Purpose:
- To investigate the correlation between βIII-tubulin expression levels and the sensitivity of A549/Taxol cells to Paclitaxel.
- To evaluate the effects of RNA interference-mediated βIII-tubulin inhibition on cell cycle progression and apoptosis in A549/Taxol cells.
Summary:
- RNA interference effectively reduced βIII-tubulin mRNA and protein levels in A549/Taxol cells, with siRNA-1 showing the highest efficiency.
- Down-regulation of βIII-tubulin significantly enhanced the sensitivity of A549/Taxol cells to Paclitaxel, as indicated by MTT assays.
- Inhibition of βIII-tubulin led to increased early apoptosis rates and altered cell cycle distribution (G2-M phase) in treated cells.
Impact:
- This study demonstrates that targeting βIII-tubulin can resensitize NSCLC cells to Paclitaxel, suggesting a potential therapeutic strategy to overcome chemotherapy resistance.
- The findings provide a basis for developing novel treatment approaches for lung cancer patients exhibiting resistance to microtubule-targeting agents.
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