The Role of Innate Immune Cells in Tumor Invasion and Metastasis

TMEM205 induces TAM/M2 polarization to promote cisplatin resistance in gastric cancer

Cisplatin (DDP) is a basic chemotherapy drug for gastric cancer (GC). With the increase of DDP drug concentration in clinical treatment, cancer cells gradually became resistant. Therefore, it is necessary to find effective therapeutic targets to enhance the sensitivity of GC to DDP. Studies have shown that Transmembrane protein 205 (TMEM205) is overexpressed in DDP-resistant human epidermoid carcinoma cells and correlates with drug resistance, and database analyses show that TMEM 205 is also overexpressed in GC, but its role in cisplatin-resistant gastric cancer remains unclear. In this study, we chose a variety of experiments in vivo and vitro, aiming to investigate the role of TMEM 205 in cisplatin resistance in gastric cancer. The results showed that TMEM 205 promoted proliferation, stemness, epithelial-mesenchymal transition (EMT), migration and angiogenesis of gastric cancer cells through activation of the Wnt/β-catenin signaling pathway. In addition, TMEM205 promotes GC progression by inducing M2 polarization of tumor-associated macrophages (TAMs). These results suggest that TMEM205 may be an effective target to regulate the sensitivity of GC to DDP, providing a new therapeutic direction for clinical treatment.

Metastatic organotropism: a brief overview

Organotropism has been known since 1889, yet this vital component of metastasis has predominantly stayed elusive. This mini-review gives an overview of the current understanding of the underlying mechanisms of organotropism and metastases development by focusing on the formation of the pre-metastatic niche, immune defenses against metastases, and genomic alterations associated with organotropism. The particular case of brain metastases is also addressed, as well as the impact of organotropism in cancer therapy. The limited comprehension of the factors behind organotropism underscores the necessity for efficient strategies and treatments to manage metastases.

Discovery of a new marker to identify myeloid cells associated with metastatic breast tumours

BACKGROUND

Myeloid cells play an essential role in cancer metastasis. The phenotypic diversity of these cells during cancer development has attracted great interest; however, their functional heterogeneity and plasticity have limited their role as prognostic markers and therapeutic targets.

METHODS

To identify markers associated with myeloid cells in metastatic tumours, we compared transcriptomic data from immune cells sorted from metastatic and non-metastatic mammary tumours grown in BALB/cJ mice. To assess the translational relevance of our in vivo findings, we assessed human breast cancer biopsies and evaluated the association between arginase 1 protein expression in breast cancer tissues with tumour characteristics and patient outcomes.

RESULTS

Among the differentially expressed genes, arginase 1 (ARG1) showed a unique expression pattern in tumour-infiltrating myeloid cells that correlated with the metastatic capacity of the tumour. Even though ARG1-positive cells were found almost exclusively inside the metastatic tumour, ARG1 protein was also present in the plasma. In human breast cancer biopsies, the presence of ARG1-positive cells was strongly correlated with high-grade proliferating tumours, poor prognosis, and low survival.

CONCLUSION

Our findings highlight the potential use of ARG1-positive myeloid cells as an independent prognostic marker to evaluate the risk of metastasis in breast cancer patients.

Unveiling the Immune Microenvironment's Role in Breast Cancer: A Glimpse into Promising Frontiers

Breast cancer (BC), one of the most widespread and devastating diseases affecting women worldwide, presents a significant public health challenge. This review explores the emerging frontiers of research focused on deciphering the intricate interplay between BC cells and the immune microenvironment. Understanding the role of the immune system in BC is critical as it holds promise for novel therapeutic approaches and precision medicine strategies. This review delves into the current literature regarding the immune microenvironment's contribution to BC initiation, progression, and metastasis. It examines the complex mechanisms by which BC cells interact with various immune cell populations, including tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs). Furthermore, this review highlights the impact of immune-related factors, such as cytokines and immune checkpoint molecules. Additionally, this comprehensive analysis sheds light on the potential biomarkers associated with the immune response in BC, enabling early diagnosis and prognostic assessment. The therapeutic implications of targeting the immune microenvironment are also explored, encompassing immunotherapeutic strategies and combination therapies to enhance treatment efficacy. The significance of this review lies in its potential to pave the way for novel therapeutic interventions, providing clinicians and researchers with essential knowledge to design targeted and personalized treatment regimens for BC patients.

Differential Regulation of Innate Lymphoid Cells in Human and Murine Oral Squamous Cell Carcinoma

Oral squamous cell carcinomas (OSCC) remain a major healthcare burden in Asian countries. In Pakistan alone, it is the most common cancer in males and second only to breast cancer in females. Alarmingly, treatment options for OSCC remain limited. With this context, investigations made to explore the inflammatory milieu of OSCC become highly relevant, with the hope of practicing immunotherapeutic approaches to address this highly prevalent tumor. We investigated the newly identified innate lymphoid cells (ILCs) and associated cytokines in well-defined human oral squamous cell carcinoma (OSCC) as well as in a 7,12-dimethylbenz[a]anthracene (DMBA)-induced murine model of OSCC using flow cytometry and quantitative real-time polymerase chain reaction (qPCR). We further went on to explore molecular circuitry involved in OSCC by developing a murine model of OSCC and using an α-Thy1 antibody to inhibit ILCs. Amongst the ILCs that we found in human OSCC, ILC3 (23%) was the most abundant, followed by ILC2 (17%) and ILC1 (1%). Mice were divided into four groups: DMBA (n = 33), DMBA+antibody (Ab) (n = 30), acetone (n = 5), and control (n = 5). In murine OSCC tissues, ILC1 and ILC3 were down-infiltrated, while ILC2 remained unchanged compared to controls. Interestingly, compared to the controls (DMBA group), mice treated with the α-Thy1 antibody showed fewer numbers of large tumors, and a larger percentage of these mice were tumor-free at this study's end point. We present novel data on the differential expansion/downsizing of ILCs in OSCC, which provides a pivotal basis to dive deeper into molecular circuitry and the OSCC tumor niche to devise novel diagnostic, therapeutic, and prognostic strategies to prevent/treat oral cancers.

Heterogeneity of Group 2 Innate Lymphoid Cells Defines Their Pleiotropic Roles in Cancer, Obesity, and Cardiovascular Diseases

Group 2 innate lymphoid cells (ILC2s) are typically known for their ability to respond rapidly to parasitic infections and play a pivotal role in the development of certain allergic disorders. ILC2s produce cytokines such as Interleukin (IL)-5 and IL-13 similar to the type 2 T helper (Th2) cells. Recent findings have highlighted that ILC2s, together with IL-33 and eosinophils, participate in a considerably broad range of physiological roles such as anti-tumor immunity, metabolic regulation, and vascular disorders. Therefore, the focus of the ILC2 study has been extended from conventional Th2 responses to these unexplored areas of research. However, disease outcomes accompanied by ILC2 activities are paradoxical mostly in tumor immunity requiring further investigations. Although various environmental factors that direct the development, activation, and localization of ILC2s have been studied, IL-33/ILC2/eosinophil axis is presumably central in a multitude of inflammatory conditions and has guided the research in ILC2 biology. With a particular focus on this axis, we discuss ILC2s across different diseases.

(Dis)similarities between the Decidual and Tumor Microenvironment

Placenta-specific trophoblast and tumor cells exhibit many common characteristics. Trophoblast cells invade maternal tissues while being tolerated by the maternal immune system. Similarly, tumor cells can invade surrounding tissues and escape the immune system. Importantly, both trophoblast and tumor cells are supported by an abetting microenvironment, which influences invasion, angiogenesis, and immune tolerance/evasion, among others. However, in contrast to tumor cells, the metabolic, proliferative, migrative, and invasive states of trophoblast cells are under tight regulatory control. In this review, we provide an overview of similarities and dissimilarities in regulatory processes that drive trophoblast and tumor cell fate, particularly focusing on the role of the abetting microenvironments.