Matrine inhibits ovarian cancer cell viability and promotes apoptosis by regulating the ERK/JNK signaling pathway via p38MAPK

Abstract

Ovarian cancer displays the highest mortality rate among all types of gynecological cancer worldwide. The survival of patients with ovarian cancer remains poor due to poor responses to anticancer treatments. The present study aimed to investigate the therapeutic effects and potential mechanism underlying matrine in ovarian cancer tissues, ovarian cancer cells and a CAOV‑3‑derived tumor‑bearing mouse model. MTT, migration, invasion, flow cytometry, immunofluorescence and immunohistochemistry assays were performed to assess the inhibitory effects of matrine on ovarian cancer. A xenograft ovarian cancer mouse model was established and treated with matrine or PBS. The results demonstrated that compared with the control group, matrine significantly induced ovarian cancer cell apoptosis by upregulating caspase‑8 and Fas cell surface death receptor (Fas) expression levels, and downregulating Bcl‑2 and Bcl‑xl expression levels. Moreover, compared with the control group, matrine significantly inhibited ovarian cancer cell viability, migration and invasion by downregulating metastasis associated protein‑1, fibronectin, angiotensin II type 2 receptor-interacting protein 3a and H high mobility group AT‑hook 2 expression levels. Compared with the control group, matrine significantly increased p38MAPK, phosphorylated (p)ERK/ERK and pJNK/JNK expression levels in ovarian cancer cells. p38MAPK knockdown significantly downregulated p38MAPK, pERK/ERK and pJNK/JNK expression levels compared with the control group, which significantly promoted ovarian cancer cell viability, migration and invasion. In vivo experiments demonstrated that compared with the control group, matrine significantly suppressed tumor growth by markedly upregulating p38MAPK, ERK and JNK expression levels. The immunohistochemistry results demonstrated that caspase‑8 and Fas expression levels were notably increased, whereas Bcl‑2 and Bcl‑xl expression levels were obviously decreased in matrine‑treated tumors compared with PBS‑treated tumors. In conclusion, the present study demonstrated that matrine inhibited ovarian cancer cell viability, migration and invasion, but induced cell apoptosis, suggesting that matrine may serve as a promising anticancer agent for the treatment of ovarian cancer.

Keywords: matrine; ovarian cancer; apoptosis; ERK/JNK signaling pathway; p38MAPK.

Figure 1.

Matrine suppresses ovarian cancer cell viability, migration and invasion by downregulating metastasis-associated genes. CAOV-3 cell (A) viability, (B) migration and (C) invasion. Protein expression levels of (D) ATIP3a, HMGA2, (E) MTA-1 and FN in CAOV-3 cells. **P<0.01. ATIP3a, angiotensin II type 2 receptor-interacting protein 3a; HMGA2, H high mobility group AT-hook 2; MTA-1, metastasis associated protein-1; FN, fibronectin.

Figure 2.

Matrine promotes ovarian cancer cell apoptosis via the extrinsic apoptotic signaling pathway. (A) CAOV-3 cell apoptosis. Protein expression levels of (B) Caspase-8, Fas, (C) Bcl-2, Bcl-xl, (D) Caspase-9 and Cyto c in CAOV-3 cells. Expression levels of (E) DR2, DR5, (F) AKT and NF-κB in CAOV-3 cells. **P<0.01. Fas, Fas cell surface death receptor; Cyto c, cytochrome c.

Figure 3.

Matrine inhibits ovarian cancer cell viability, migration and invasion by downregulating the p38-mediated ERK/JNK signaling pathway. (A) Effect of matrine on p38MAPK, pERK/ERK and pJNK/JNK in CAOV-3 cells. (B) Effect of p38 knockdown on p38MAPK protein expression. (C) Effects of p38 knockdown on p38MAPK, pERK/ERK and pJNK/JNK protein expression levels in matrine-treated CAOV-3 cells. Effects of p38 knockdown on matrine-treated CAOV-3 cell (D) viability, (E) migration, invasion and (F) apoptosis. Effects of p38 knockdown on (G) ATIP3a, HMGA2, (H) DR2 and DR5 expression levels in matrine-treated CAOV-3 cells. Arrows indicate protein immunoreactivity in CAOV-3 cells. **P<0.01. p, phosphorylated; ATIP3a, angiotensin II type 2 receptor-interacting protein 3a; HMGA2, H high mobility group AT-hook 2; si, small interfering RNA; ns, not significant; NC, negative control.

Figure 4.

In vivo effects of matrine treatment on ovarian cancer growth and the survival of ovarian carcinoma-bearing mice. (A) Matrine inhibits tumor growth in CAOV-3-derived tumor-bearing mice compared with the control group. (B) p38MAPK, ERK and JNK expression levels in CAOV-3-derived tumors. (C) Apoptotic bodies in CAOV-3-derived tumors were detected by performing TUNEL assays. Expression levels of (D) Caspase-8, Fas, (E) Bcl-2 and Bcl-xl in CAOV-3-derived tumors. (F) Survival of CAOV-3-derived tumor-bearing mice in 120-day observation. **P<0.01. Fas, Fas cell surface death receptor.