scholarly journals Tumor Dormancy and Interplay with Hypoxic Tumor Microenvironment

2019 ◽  
Vol 20 (17) ◽  
pp. 4305 ◽  
Author(s):  
Elena Butturini ◽  
Alessandra Carcereri de Prati ◽  
Diana Boriero ◽  
Sofia Mariotto

The tumor microenvironment is a key factor in disease progression, local resistance, immune-escaping, and metastasis. The rapid proliferation of tumor cells and the aberrant structure of the blood vessels within tumors result in a marked heterogeneity in the perfusion of the tumor tissue with regions of hypoxia. Although most of the tumor cells die in these hypoxic conditions, a part of them can adapt and survive for many days or months in a dormant state. Dormant tumor cells are characterized by cell cycle arrest in G0/G1 phase as well as a low metabolism, and are refractive to common chemotherapy, giving rise to metastasis. Despite these features, the cells retain their ability to proliferate when conditions improve. An understanding of the regulatory machinery of tumor dormancy is essential for identifying early cancer biomarkers and could provide a rationale for the development of novel agents to target dormant tumor cell populations. In this review, we examine the current knowledge of the mechanisms allowing tumor dormancy and discuss the crucial role of the hypoxic microenvironment in this process.

Cancers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 4916
Author(s):  
Julie S. Di Martino ◽  
Tasmiah Akhter ◽  
Jose Javier Bravo-Cordero

While most primary tumors can be effectively treated, therapeutics fail to efficiently eliminate metastases. Metastases arise from cancer cells that leave the primary tumor and seed distant sites. Recent studies have shown that cancer cells disseminate early during tumor progression and can remain dormant for years before they resume growth. In these metastatic organs, cancer cells reside in microenvironments where they interact with other cells, but also with the extracellular matrix (ECM). The ECM was long considered to be an inert, non-cellular component of tissues, providing their architecture. However, in recent years, a growing body of evidence has shown that the ECM is a key driver of cancer progression, and it can exert effects on tumor cells, regulating their metastatic fate. ECM remodeling and degradation is required for the early steps of the metastatic cascade: invasion, tumor intravasation, and extravasation. Similarly, ECM molecules have been shown to be important for metastatic outgrowth. However, the role of ECM molecules on tumor dormancy and their contribution to the dormancy-supportive niches is not well understood. In this perspective article, we will summarize the current knowledge of ECM and its role in tumor metastasis and dormancy. We will discuss how a better understanding of the individual components of the ECM niche and their roles mediating the dormant state of disseminated tumor cells (DTCs) will advance the development of new therapies to target dormant cells and prevent metastasis outgrowth.


2021 ◽  
Vol 14 ◽  
Author(s):  
Saurabh Satija ◽  
Harpreet Kaur ◽  
Murtaza M. Tambuwala ◽  
Prabal Sharma ◽  
Manish Vyas ◽  
...  

Hypoxia is an integral part of tumor microenvironment, caused primarily due to rapidly multiplying tumor cells and a lack of proper blood supply. Among the major hypoxic pathways, HIF-1 transcription factor activation is one of the widely investigated pathways in the hypoxic tumor microenvironment (TME). HIF-1 is known to activate several adaptive reactions in response to oxygen deficiency in tumor cells. HIF-1 has two subunits, HIF-1β (constitutive) and HIF-1α (inducible). The HIF-1α expression is largely regulated via various cytokines (through PI3K-ACT-mTOR signals), which involves the cascading of several growth factors and oncogenic cascades. These events lead to the loss of cellular tumor suppressant activity through changes in the level of oxygen via oxygen-dependent and oxygen-independent pathways. The significant and crucial role of HIF in cancer progression and its underlying mechanisms have gained much attention lately among the translational researchers in the fields of cancer and biological sciences, which have enabled them to correlate these mchanisms with various other disease modalities. In the present review, we have summarized the key findings related to the role of HIF in the progression of tumors.


2020 ◽  
Author(s):  
Mei-Zhen Zou ◽  
Wen-Long Liu ◽  
Han-Shi Chen ◽  
Xue-Feng Bai ◽  
Fan Gao ◽  
...  

Abstract The hypoxic tumor microenvironment is characterized by disordered vasculature and rapid proliferation of tumors, resulting from tumor invasion, progression and metastasis. The hypoxic conditions restrict efficiency of tumor therapies, such as chemotherapy, radiotherapy, phototherapy and immunotherapy, leading to serious results of tumor recurrence and high mortality. Recently, research has concentrated on developing functional nanomaterials to treat hypoxic tumors. In this review, we categorize such nanomaterials into (i) nanomaterials that elevate oxygen levels in tumors for enhanced oxygen-dependent tumor therapy and (ii) nanomaterials with diminished oxygen dependence for hypoxic tumor therapy. To elevate oxygen levels in tumors, oxygen-carrying nanomaterials, oxygen-generating nanomaterials and oxygen-economizing nanomaterials can be used. To diminish oxygen dependence of nanomaterials for hypoxic tumor therapy, therapeutic gas-generating nanomaterials and radical-generating nanomaterials can be used. The biocompatibility and therapeutic efficacy of these nanomaterials are discussed.


2020 ◽  
Vol 9 (8) ◽  
pp. 2418
Author(s):  
Roberto Tamma ◽  
Girolamo Ranieri ◽  
Giuseppe Ingravallo ◽  
Tiziana Annese ◽  
Angela Oranger ◽  
...  

Diffuse large B cell lymphoma (DLBCL), known as the most common non-Hodgkin lymphoma (NHL) subtype, is characterized by high clinical and biological heterogeneity. The tumor microenvironment (TME), in which the tumor cells reside, is crucial in the regulation of tumor initiation, progression, and metastasis, but it also has profound effects on therapeutic efficacy. The role of immune cells during DLBCL development is complex and involves reciprocal interactions between tumor cells, adaptive and innate immune cells, their soluble mediators and structural components present in the tumor microenvironment. Different immune cells are recruited into the tumor microenvironment and exert distinct effects on tumor progression and therapeutic outcomes. In this review, we focused on the role of macrophages, Neutrophils, T cells, natural killer cells and dendritic cells in the DLBCL microenvironment and their implication as target for DLBCL treatment. These new therapies, carried out by the induction of adaptive immunity through vaccination or passive of immunologic effectors delivery, enhance the ability of the immune system to react against the tumor antigens inducing the destruction of tumor cells.


2020 ◽  
Vol 8 (24) ◽  
pp. 5312-5319 ◽  
Author(s):  
Daoming Zhu ◽  
Meng Lyu ◽  
Wei Jiang ◽  
Meng Suo ◽  
Qinqin Huang ◽  
...  

Although radiotherapy (RT) has been an effective therapeutic regimen for regulating most solid tumors, its effect is limited by the hypoxic tumor microenvironment and radio-tolerance of tumor cells to a large extent.


2020 ◽  
Vol 35 (1_suppl) ◽  
pp. 8-11 ◽  
Author(s):  
Paola Nisticò ◽  
Gennaro Ciliberto

Our view of cancer biology radically shifted from a “cancer-cell-centric” vision to a view of cancer as an organ disease. The concept that genetic and/or epigenetic alterations, at the basis of cancerogenesis, are the main if not the exclusive drivers of cancer development and the principal targets of therapy, has now evolved to include the tumor microenvironment in which tumor cells can grow, proliferate, survive, and metastasize only within a favorable environment. The interplay between cancer cells and the non-cellular and cellular components of the tumor microenvironment plays a fundamental role in tumor development and evolution both at the primary site and at the level of metastasis. The shape of the tumor cells and tumor mass is the resultant of several contrasting forces either pro-tumoral or anti-tumoral which have at the level of the tumor microenvironment their battle field. This crucial role of tumor microenvironment composition in cancer progression also dictates whether immunotherapy with immune checkpoint inhibitor antibodies is going to be efficacious. Hence, tumor microenvironment deconvolution has become of great relevance in order to identify biomarkers predictive of efficacy of immunotherapy. In this short paper we will briefly review the relationship between inflammation and cancer, and will summarize in 10 short points the key concepts learned so far and the open challenges to be solved.


Cells ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1539 ◽  
Author(s):  
Peter Ping Lin

Hematogenous and lymphogenous cancer metastases are significantly impacted by tumor neovascularization, which predominantly consists of blood vessel-relevant angiogenesis, vasculogenesis, vasculogenic mimicry, and lymphatic vessel-related lymphangiogenesis. Among the endothelial cells that make up the lining of tumor vasculature, a majority of them are tumor-derived endothelial cells (TECs), exhibiting cytogenetic abnormalities of aneuploid chromosomes. Aneuploid TECs are generated from “cancerization of stromal endothelial cells” and “endothelialization of carcinoma cells” in the hypoxic tumor microenvironment. Both processes crucially engage the hypoxia-triggered epithelial-to-mesenchymal transition (EMT) and endothelial-to-mesenchymal transition (EndoMT). Compared to the cancerization process, endothelialization of cancer cells, which comprises the fusion of tumor cells with endothelial cells and transdifferentiation of cancer cells into TECs, is the dominant pathway. Tumor-derived endothelial cells, possessing the dual properties of cancerous malignancy and endothelial vascularization ability, are thus the endothelialized cancer cells. Circulating tumor-derived endothelial cells (CTECs) are TECs shed into the peripheral circulation. Aneuploid CD31+ CTECs, together with their counterpart CD31- circulating tumor cells (CTCs), constitute a unique pair of cellular circulating tumor biomarkers. This review discusses a proposed cascaded framework that focuses on the origins of TECs and CTECs in the hypoxic tumor microenvironment and their clinical implications for tumorigenesis, neovascularization, disease progression, and cancer metastasis. Aneuploid CTECs, harboring hybridized properties of malignancy, vascularization and motility, may serve as a unique target for developing a novel metastasis blockade cancer therapy.


Cells ◽  
2018 ◽  
Vol 7 (8) ◽  
pp. 93 ◽  
Author(s):  
James Jabalee ◽  
Rebecca Towle ◽  
Cathie Garnis

Extracellular vesicles (EVs) are a heterogeneous collection of membrane-bound structures that play key roles in intercellular communication. EVs are potent regulators of tumorigenesis and function largely via the shuttling of cargo molecules (RNA, DNA, protein, etc.) among cancer cells and the cells of the tumor stroma. EV-based crosstalk can promote proliferation, shape the tumor microenvironment, enhance metastasis, and allow tumor cells to evade immune destruction. In many cases these functions have been linked to the presence of specific cargo molecules. Herein we will review various types of EV cargo molecule and their functional impacts in the context of oncology.


2019 ◽  
Vol 20 (10) ◽  
pp. 2416 ◽  
Author(s):  
Donatella Aldinucci ◽  
Cinzia Borghese ◽  
Naike Casagrande

Classic Hodgkin lymphoma (cHL) is characterized by a few tumor cells surrounded by a protective, immunosuppressive tumor microenvironment composed of normal cells that are an active part of the disease. Hodgkin and Reed–Sternberg (HRS) cells evade the immune system through a variety of different mechanisms. They evade antitumor effector T cells and natural killer cells and promote T cell exhaustion. Using cytokines and extracellular vesicles, they recruit normal cells, induce their proliferation and “educate” (i.e. reprogram) them to become immunosuppressive and protumorigenic. Therefore, alternative treatment strategies are being developed to target not only tumor cells but also the tumor microenvironment. Here we summarize current knowledge on the ability of HRS cells to build their microenvironment and to educate normal cells to become immunosuppressive. We also describe therapeutic strategies to counteract formation of the tumor microenvironment and related processes leading to T cell exhaustion and repolarization of immunosuppressive tumor-associated macrophages.


Sign in / Sign up

Export Citation Format

Share Document