title: Role of tumor-associated macrophages in the progression of hepatocellular carcinoma.
abstract: Recent studies have shown that the tumor microenvironment plays an important role in cancer progression. Tumor-associated macrophages (TAMs), in particular, have been found to be associated with tumor progression. Macrophages have multiple biological roles, including antigen presentation, target cell cytotoxicity, removal of foreign bodies, tissue remodeling, regulation of inflammation, induction of immunity, thrombosis, and endocytosis. Recent immunological studies have identified two distinct states of polarized macrophage activation: the classically activated (M1) and the alternatively activated (M2) macrophage phenotypes. Bacterial moieties such as lipopolysaccharides and the Th1 cytokine interferon-γ polarize macrophages toward the M1 phenotype. The M2 polarization was discovered as a response to the Th2 cytokine interleukin-4. In general, M2 macrophages exert immunoregulatory activity, participate in polarized Th2 responses, and aid tumor progression. TAMs have recently been found to play an important role in hepatocellular carcinoma (HCC) progression. Based on the properties of TAMs, obtained from pathological examination of resected specimens, we have identified new therapeutic approaches, involving the targeting of TAMs with adjuvant therapy after hepatic resection for HCC. This review discusses the roles of TAM in HCC progression and the possibility of new therapies targeting TAMs.
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan. kshirabe@surg2.med.kyushu-u.ac.jp
authors: Ken
authors: K
authors: Shirabe
authors: Yohei
authors: Y
authors: Mano
authors: Jun
authors: J
authors: Muto
authors: Rumi
authors: R
authors: Matono
authors: Takashi
authors: T
authors: Motomura
authors: Takeo
authors: T
authors: Toshima
authors: Kazuki
authors: K
authors: Takeishi
authors: Hidekaki
authors: H
authors: Uchiyama
authors: Tomoharu
authors: T
authors: Yoshizumi
authors: Akinobu
authors: A
authors: Taketomi
authors: Masaru
authors: M
authors: Morita
authors: Shunichi
authors: S
authors: Tsujitani
authors: Yoshihisa
authors: Y
authors: Sakaguchi
authors: Yoshihiko
authors: Y
authors: Maehara
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000276:immunology* / Q000473:pathology / Q000628:therapy; D018450:Disease Progression; D006801:Humans; D007167:Immunotherapy / Q000639:trends; D007249:Inflammation; D008113:Liver Neoplasms / Q000276:immunology* / Q000473:pathology / Q000628:therapy; D008262:Macrophage Activation; D008264:Macrophages / Q000276:immunology* / Q000473:pathology / Q000502:physiology; D009362:Neoplasm Metastasis / Q000276:immunology / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000276:immunology / Q000473:pathology; D010641:Phenotype