Extracts from Huangqi (Radix Astragali Mongoliciplus) and Ezhu (Rhizoma Curcumae Phaeocaulis) inhibit Lewis lung carcinoma cell growth in a xenograft mouse model by impairing mitogen-activated protein kinase signaling, vascular endothelial growth factor production, and angiogenesis

OBJECTIVE

To study the anti-tumor effects of the extracts from Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) on the growth of Lewis lung carcinoma (LLC) in a xenograft mouse model and to investigate the possible underlying mechanism.

METHODS

LLC tumor-bearing C57BL/6 mice were treated with normal saline, cisplatin (2 mg/kg intraperitoneally every other day), or Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) (1∶1, 2∶1, or 3∶1 ratio; 5 , 8 , or 11 g/kg crude drug intragastrically every day) for 15 d. Body weights and tumor volumes were measured every other day. Tumors were excised on day 15 and analyzed. Tumor microvessel density (MVD) was assessed by immunohistochemical staining of CD34; and expression of vascular endothelial cell growth factor (VEGF), the mitogen-activated protein kinases p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinases 1 and 2 (ERK1/2), and Jun N-terminal kinase (JNK) and their phosphorylated forms were assessed by Western blotting.

RESULTS

Treatment with cisplatin caused a significant loss of body weight compared with controls, whereas Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) extract combinations had no effect. Extracts from Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) significantly decreased tumor weight and tumor MVD compared with controls, and at the 3∶1 treatment group had similar efficacy to cisplatin in reducing MVD. Tumors from Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) treatments also showed decreased p38 MAPK, p-p38 MAPK, ERK1/2, p-ERK1/2, JNK, and p-JNK expression compared with the control group (all P < 0.01). VEGF protein expression was significantly reduced in the 2∶1 and 3∶1 treatment groups compared with the control group (P < 0.01).

CONCLUSION

Extracts from Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) hindered LLC growth in the xenograft mouse model, possibly via inhibition of the MAPK signaling pathway, VEGF production, and tumor angiogenesis.

Effect of optimal combination of Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) on proliferation and apoptosis of A549 lung cancer cells

OBJECTIVE

To investigate the effect of optimal combination (E) of Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) on proliferation and apoptosis of A549 lung cancer cells and the possible mechanism underpinning the action.

METHODS

A uniform design method was used to optimize the E of Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) in A549 lung cancer cells. MTS assay was applied to analyze the effect of the component formula of Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis) on A549 cells viability in various uniform design groups. A549 cells with exponential growth in routine culture were exposed to CoCl2 (200 μmol/L) to mimic hypoxic conditions. Group 0 was treated with RPMI-1640, the group CoCl2 was treated with CoCl2 (200 μmol/L), the group DDP + CoCl2 was treated with 4 mg/L Cisplatin injection (DDP) + CoCl2 (200 μmol/L), and the drug group was treated with various dose of E (0.5E, 1E, 2E) + CoCl2 (200 μmol/L). All groups were cultured for 24 h. Cell apoptosis was measured by Annexin V-FITC/propidium iodide double staining and flow cytometry. Western blot assay and quantitative real-time polymerase chain reaction (qRT-PCR) were employed to detect the protein and mRNA expression of B-celllymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax) and cysteinyl aspartate specific proteinase-3 (caspase-3).

RESULTS

The E obtained by the uniform design was comprise of 200 mg/L Astragalus polysaccharide (X1) and 32 mg/L Curcumin (X3). Group DDP+CoCl2, group 1E + CoCl2 and group 2E + CoCl2 promoted the apoptosis of A549 cells (P < 0.05). Group 1E + CoCl2 and group 2E + CoCl2 had no statistically significant differences compared with the group DDP + CoCl2 (P > 0.05). Compared with group 0, various doses of E + CoCl2 could up-regulate the expression of Bax and caspase-3 and down-regulate the expression of Bcl-2 at protein and mRNA levels (P < 0.05).

CONCLUSION

Astragalus polysaccharide and Curcumin was the optimal combination of Huangqi (Radix Astragali Mongolici) and Ezhu (Rhizoma Curcumae Phaeocaulis). E promoted the apoptosis of A549 cells. Combination of Astragalus polysaccharide and Curcumin increased the expression of Bax and caspase-3, and decreased the expression of Bcl-2 to initiate apoptosis in A549 cells under chemical-induced hypoxia.