[Advances in study of macrophages in chemotherapy resistance of cancer].

As extremely important inflammatory cells in the tumor microenvironment, tumor-associated macrophages (TAMs) can secrete a variety of chemokines and cytokines, which play an important role in the occurrence of tumor growth and metastasis. Recent years, increasing studies have shown that macrophages are associated with tumor chemotherapy sensitivity. The chemical substances produced by macrophages affect the efficacy of chemotherapeutic agents. In addition, some chemotherapeutic agents have an effect on the recruitment and bioactivity of macrophages in the tumor issue, which influences the anti-tumor efficacy of chemotherapy drugs. In this review, we summarize the roles of macrophages in the chemotherapy resistance, including the regulatory mechanism and the strategy of targeting macrophages.

[Combination of lapatinib with chlorogenic acid inhibits breast cancer metastasis by suppressing macrophage M2 polarization].

OBJECTIVE: To determine the effect of the combination of lapatinib with chlorogenic acid on metastasis of breast cancer in mouse model. METHODS: The classical macrophage M2 polarization model induced by interlukin13in vitro was adopted in the study. Flow cytometric analysis was performed to detect the expression of M2 marker CD206. The transcription of M2-associated genes was measured by RT-PCR. HE staining was used to analyze the metastatic nodes of breast cancer in lungs of MMTV-PyVT mice. Immunostaining analysis was used to detect the expression of related proteins in breast cancer. RESULTS: The combination of lapatinib and chlorogenic acid inhibited the expression of CD206 induced by IL-13[(42.17%±2.59%) vs (61.15%±7.58%), P<0.05]. The combination more markedly suppressed expression of M2-associated gene Ym1 than lapatinib alone[(0.9±0.1) vs (1.8±0.0), P<0.05]. The combination of lapatinib and chlorogenic acid significantly reduced metastatic nodes in lung[P<0.05], and also significantly decreased the percentage of CD206(+) cells in breast cancer compared to controls[(6.08%±2.60%) vs(29.04%±5.86%), P<0.05]. CONCLUSION: The combination of lapatinib and chlorogenic acid can effectively inhibit macrophage M2 polarization and metastasis of breast cancer.

[Statins enhance anti-tumor effect of suberoylanilide hydroxamic acid on human non-small cell lung carcinoma cells].

OBJECTIVE: To evaluate the anti-tumor effect of the combination of suberoylanilide hydroxamic acid(SAHA) with statins(lovastatin or simvastatin) on non-small cell lung carcinoma(NSCLC) cells. METHODS: Human NSCLC A549 cells were treated with SAHA in combination of lovastatin or simvastatin. The cell growth was analyzed by SRB method, and the apoptosis of A549 cells was assessed by flow cytometer. The expression of cleaved poly-ADP-ribose polymerase(cleaved-PARP) and p21 protein was analyzed by Western-blotting when A549 cells were challenged with 2.5µmol/L SAHA and 5µmol/L lovastatin. RESULTS: Lovastatin and simvastatin synergized SAHA in the inhibition of A549 cells. SAHA induced apoptosis was also enhanced by lovastatin. Treatment with 2.5µmol/L SAHA significantly up-regulated the expression of p21 protein in 48 h, while the protein expression was reduced in combined treatment with 5µmol/L lovastatin. CONCLUSION: Statins can synergize the anti-tumor effect of SAHA in human NSCLC cells through a p21-dependent way.