Prognostic significance of tumor-associated macrophages polarization markers in lung cancer: a pooled analysis of 5105 patients

Clinicopathologic and prognostic significance of tumor-associated macrophages in cervical cancer: a systematic review and meta-analysis

OBJECTIVES

The role of tumor-associated macrophages (TAMs) in cervical cancer (CC) remains controversial. Here, we report a meta-analysis of the association between TAMs infiltration and clinical outcomes.

METHODS

PubMed, Embase, Web of Science, and CNKI were searched systematically from inception until December 20, 2023. Studies involving TAMs and prognosis, clinical, or pathological features were included. Quality assessments of the selected studies were assessed. The fixed-effect or random-effects model, standard mean difference (SMD), odds ratios (OR), or hazard ratios (HR) with 95% confidence intervals (CIs) were used as the effect size estimate.

RESULTS

26 eligible studies with 2,295 patients were identified. Our meta-analysis revealed that TAMs were overexpressed in CC (OR = 12.93, 95% CI = 7.73-21.61 and SMD = 1.58, 95% CI = 0.95-2.21) and that elevated TAM levels were strongly associated with lymph node metastasis (LNM) (SMD = 0.51, 95% CI = 0.90-2.01) and FIGO stages (SMD = 0.46, 95% CI = 0.08-0.85). Subgroup analysis indicated a significant positive correlation between LNM and TAMs density in tumor stroma, but not in cancer nests (SMD = 0.58, 95% CI = 0.31-0.58). Furthermore, in early stage, a stronger correlation exists between LNM and TAM density (SMD = 1.21, 95% CI = 0.75-1.66). In addition, it revealed that patients with high TAMs expression had poorer overall survival (OS) (HR = 2.55 95% CI = 1.59-4.07) and recurrence-free survival (RFS) (HR = 2.17, 95% CI = 1.40-3.35).

CONCLUSIONS

Our analyses suggest that a high density of TAMs predicts adverse outcomes in CC.

Multiplexed analysis of macrophage polarisation in pulmonary metastases of microsatellite stable colorectal cancer

Tumour-associated macrophages (TAMs) express a continuum of phenotypes ranging from an anti-tumoural M1-like phenotype to a pro-tumoural M2-like phenotype. During cancer progression, TAMs may shift to a more M2-like polarisation state, but the role of TAMs in CRC metastases is unclear. We conducted a comprehensive spatial and prognostic analysis of TAMs in CRC pulmonary metastases and corresponding primary tumours using multiplexed immunohistochemistry and machine learning-based image analysis. We obtained data from 106 resected pulmonary metastases and 74 corresponding primary tumours. TAMs in the resected pulmonary metastases were located closer to the cancer cells and presented a more M2-like polarised state in comparison to the primary tumours. Higher stromal M2-like macrophage densities in the invasive margin of pulmonary metastases were associated with worse 5-year overall survival (HR 3.19, 95% CI 1.35-7.55, p = 0.008). The results of this study highlight the value of multiplexed analysis of macrophage polarisation in cancer metastases and might have clinical implications in future cancer therapy.

The role of tumor-associated macrophages in lung cancer: From mechanism to small molecule therapy

Tumor-associated macrophages (TAMs) are the main component of tumor-infiltrating immune cells in the lung tumor microenvironment. TAMs recruited to the lung cancer can create a suitable microenvironment for the growth and metastasis of lung cancer by secreting tumor promoting factors and interfering with the function of T cells. Currently, numerous studies have reported that small molecular drugs affect lung cancer progression by selectively targeting TAMs. The main ways include blocking the recruitment of monocytes or eliminating existing TAMs in tumor tissue, reprogramming TAMs into pro-inflammatory M1 macrophages or inhibiting M2 polarization of macrophages, interrupting the interaction between tumor cells and macrophages, and modulating immune function. Signaling pathways or cytokines such as CCL8, CCL2/CCR2, CSF-1/CSF-1R, STAT3, STAT6, MMPs, Caspase-8, AMPK α1, TLR3, CD47/SIRPα, have been reported to be involved in this process. Based on summarizing the role and mechanisms of TAMs in lung cancer progression, this paper particularly focuses on systematically reviewing the effects and mechanisms of small molecule drugs on lung cancer TAMs, and classified the small molecular drugs according to the way they affect TAMs. The study aims to provide new perspectives and potential therapeutic drugs for targeted macrophages treatment in lung cancer, which is of great significance and will provide more options for immunotherapy of lung cancer.

Nanomedicine - Immune System Interactions: Limitations and Opportunities for the Treatment of Cancer

Nanoparticles interact with immune cells in many different ways. These interactions are crucially important for determining nanoparticles' ability to be used for cancer therapy. Traditionally, strategies such as PEGylation have been employed to reduce (the kinetics of) nanoparticle uptake by immune cells, to endow them with long circulation properties, and to enable them to exploit the Enhanced Permeability and Retention (EPR) effect to accumulate in tumors. More recently, with immunotherapy becoming an increasingly important cornerstone in the clinical management of cancer, ever more research efforts in academia and industry are focusing on specifically targeting immune cells with nanoparticles. In this chapter, we describe the barriers and opportunities of immune cell targeting with nanoparticles, and we discuss how nanoparticle-based drug delivery to specific immune cell populations in tumors as well as in secondary myeloid and lymphoid organs (such as bone marrow, lymph nodes, and spleen) can be leveraged to boost the efficacy of cancer immunotherapy.