Identification and manipulation of tumor associated macrophages in human cancers

Evading immune destruction and tumor promoting inflammation are important hallmarks in the development of cancer. Macrophages are present in most human tumors and are often associated with bad prognosis. Tumor associated macrophages come in many functional flavors ranging from what is known as classically activated macrophages (M1) associated with acute inflammation and T-cell immunity to immune suppressive macrophages (M2) associated with the promotion of tumor growth. The role of these functionally different myeloid cells is extensively studied in mice tumor models but dissimilarities in markers and receptors make the direct translation to human cancer difficult. This review focuses on recent reports discriminating the type of infiltrating macrophages in human tumors and the environmental cues present that steer their differentiation. Finally, immunotherapeutic approaches to interfere in this process are discussed

Immunotherapy of head and neck tumors

BACKGROUND: In recent years, new immunotherapeutic drugs have become available: the so-called immune checkpoint modulators. With these drugs, unprecedented treatment results have been achieved in different malignant diseases; primarily malignant melanoma, but also in various other malignomas. These achievements have revolutionized the oncologic treatment landscape. This quickly expanding research field, driven by revolutionary treatment results, has put immunotherapy in the focus of attention. OBJECTIVE: Due to rapid developments in the field of immunotherapy, this article aims at introducing, illustrating, and summarizing the field of modern immunotherapy, based on recently presented clinical data from the Annual Meeting of the American Society of Clinical Oncology (ASCO) 2015. MATERIALS AND METHODS: The most important ASCO Meeting 2015 immunotherapy trials for head and neck squamous cell carcinoma (HNSCC) were identified, summarized, and discussed with respect to the current state of research. RESULTS: The oncologic landscape of clinical trials is currently dominated by the new immune checkpoint modulating drugs. Also for HNSCC, a variety of clinical trials and substances are under way. The current primary focus of these trials is targeting and inhibiting the programmed death 1 (PD-1) axis. Cancer immunotherapy with immune checkpoint modulating drugs seems to be independent of human papilloma virus (HPV) status. Robust predictive markers for patient selection are not yet available. CONCLUSION: Current data from clinical trials with immune checkpoint modulators are promising. In the coming years, integration of these drugs into clinical routine can be expected. With regard to the public health economic burden and potential adverse events, the identification of predictive markers for patient selection is a major task for future trials