Tumor-associated macrophages (TAMs) depend on MMP1 for their cancer-promoting role

MMP1, IL-1β, sTNFR-1, and IL-6 are prognostic factors for patients with unresectable or metastatic renal cell carcinoma treated with immune checkpoint inhibitors

BACKGROUND

Few studies have reported reliable prognostic factors for immune checkpoint inhibitors (ICIs) in renal cell carcinoma (RCC). Therefore, we investigated prognostic factors in patients treated with ICIs for unresectable or metastatic RCC.

METHODS

We included 43 patients who received ICI treatment for RCC between January 2018 and October 2021. Blood samples were drawn before treatment, and 73 soluble factors in the plasma were analyzed using a bead-based multiplex assay. We examined factors associated with progression-free survival (PFS), overall survival (OS), and immune-related adverse events (irAE) using the Chi-squared test, Kaplan-Meier method, and the COX proportional hazards model.

RESULTS

Patients exhibited a median PFS and OS of 212 and 783 days, respectively. Significant differences in both PFS and OS were observed for MMP1 (PFS, p < 0.001; OS, p = 0.003), IL-1β (PFS, p = 0.021; OS, p = 0.008), sTNFR-1 (PFS, p = 0.017; OS, p = 0.005), and IL-6 (PFS, p = 0.004; OS, p < 0.001). Multivariate analysis revealed significant differences in PFS for MMP1 (hazard ratio [HR] 5.305, 95% confidence interval [CI], 1.648-17.082; p = 0.005) and OS for IL-6 (HR 23.876, 95% CI, 3.426-166.386; p = 0.001). Moreover, 26 patients experienced irAE, leading to ICI discontinuation or withdrawal. MMP1 was significantly associated with irAE (p = 0.039).

CONCLUSION

MMP1 may be associated with severe irAE, and MMP1, IL-1β, sTNFR-1, and IL-6 could serve as prognostic factors in unresectable or metastatic RCC treated with ICIs. MMP1 and IL-6 were independent predictors of PFS and OS, respectively. Thus, inhibiting these soluble factors may be promising for enhancing antitumor responses in patients with RCC treated with ICIs.

The role of tumor-associated macrophages in tumor immune evasion

BACKGROUND

Tumor growth is closely linked to the activities of various cells in the tumor microenvironment (TME), particularly immune cells. During tumor progression, circulating monocytes and macrophages are recruited, altering the TME and accelerating growth. These macrophages adjust their functions in response to signals from tumor and stromal cells. Tumor-associated macrophages (TAMs), similar to M2 macrophages, are key regulators in the TME.

METHODS

We review the origins, characteristics, and functions of TAMs within the TME. This analysis includes the mechanisms through which TAMs facilitate immune evasion and promote tumor metastasis. Additionally, we explore potential therapeutic strategies that target TAMs.

RESULTS

TAMs are instrumental in mediating tumor immune evasion and malignant behaviors. They release cytokines that inhibit effector immune cells and attract additional immunosuppressive cells to the TME. TAMs primarily target effector T cells, inducing exhaustion directly, influencing activity indirectly through cellular interactions, or suppressing through immune checkpoints. Additionally, TAMs are directly involved in tumor proliferation, angiogenesis, invasion, and metastasis. Developing innovative tumor-targeted therapies and immunotherapeutic strategies is currently a promising focus in oncology. Given the pivotal role of TAMs in immune evasion, several therapeutic approaches have been devised to target them. These include leveraging epigenetics, metabolic reprogramming, and cellular engineering to repolarize TAMs, inhibiting their recruitment and activity, and using TAMs as drug delivery vehicles. Although some of these strategies remain distant from clinical application, we believe that future therapies targeting TAMs will offer significant benefits to cancer patients.

The Tumor Stroma of Squamous Cell Carcinoma: A Complex Environment That Fuels Cancer Progression

The tumor microenvironment (TME), a complex assembly of cellular and extracellular matrix (ECM) components, plays a crucial role in driving tumor progression, shaping treatment responses, and influencing metastasis. This narrative review focuses on the cutaneous squamous cell carcinoma (cSCC) tumor stroma, highlighting its key constituents and their dynamic contributions. We examine how significant changes within the cSCC ECM-specifically, alterations in fibronectin, hyaluronic acid, laminins, proteoglycans, and collagens-promote cancer progression, metastasis, and drug resistance. The cellular composition of the cSCC TME is also explored, detailing the intricate interplay of cancer-associated fibroblasts (CAFs), mesenchymal stem cells (MSCs), endothelial cells, pericytes, adipocytes, and various immune cell populations. These diverse players modulate tumor development, angiogenesis, and immune responses. Finally, we emphasize the TME's potential as a therapeutic target. Emerging strategies discussed in this review include harnessing the immune system (adoptive cell transfer, checkpoint blockade), hindering tumor angiogenesis, disrupting CAF activity, and manipulating ECM components. These approaches underscore the vital role that deciphering TME interactions plays in advancing cSCC therapy. Further research illuminating these complex relationships will uncover new avenues for developing more effective treatments for cSCC.

Fabrication of a Coculture Organoid Model in the Biomimetic Matrix of Alginate to Investigate Breast Cancer Progression in a TAMs-Leading Immune Microenvironment

The current research models of breast cancer are usually limited in their capacity to recapitulate the tumor microenvironment in vitro. The lack of an extracellular matrix (ECM) oversimplifies cell-cell or cell-ECM cross-talks. Moreover, the lack of tumor-associated macrophages (TAMs), that can comprise up to 50% of some solid neoplasms, poses a major problem for recognizing various hallmarks of cancer. To address these concerns, a type of direct breast cancer cells (BCCs)-TAMs coculture organoid model was well developed by a sequential culture method in this study. Alginate cryogels were fabricated with appropriate physical and mechanical properties to serve as an alternative ECM. Then, our previous experience was leveraged to polarize TAMs inside of the cryogels for creating an in vitro immune microenvironment. The direct coculture significantly enhanced BCCs organoid growth and cancer aggressive phenotypes, including the stemness, migration, ECM remodeling, and cytokine secretion. Furthermore, transcriptomic analysis and protein-protein interaction networks implied certain pathways (PI3K-Akt pathway, MAPK signaling pathway, etc.) and targets (TNF, PPARG, TLR2, etc.) during breast cancer progression in a TAM-leading immune microenvironment. Future studies to advance treatment strategies for BCC patients may benefit from using this facile model to reveal and target the interactions between cancer signaling and the immune microenvironment.

Identification and validation of a novel six-gene signature based on mucinous adenocarcinoma-related gene molecular typing in colorectal cancer

BACKGROUND AND OBJECTIVES

Colorectal mucinous adenocarcinoma (MAC) is a particular pathological type that has yet to be thoroughly studied. This study aims to investigate the characteristics of colorectal MAC-related genes in colorectal cancer (CRC), explore the role of MAC-related genes in accurately classifying CRC, and further construct a prognostic signature.

METHODS

CRC samples were collected from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). MAC-related differentially expressed genes (DEGs) were analyzed in TCGA samples. Based on colorectal MAC-related genes, TCGA CRC samples were molecularly typed by the non-negative matrix factorization (NMF). According to the molecular subtype characteristics, the RiskScore signature was constructed through univariate Cox, the least absolute shrinkage and selection operator (LASSO), and multivariate Cox regression analyses. Clinical significance in CRC of the RiskScore signature was analyzed. A nomogram was further built based on the RiskScore signature.

RESULTS

From the colorectal MAC-related genes, three distinct molecular subtypes were identified. A RiskScore signature composed of six CRC subtype-related genes (CALB1, MMP1, HOXC6, ZIC2, SFTA2, and HYAL1) was constructed. Patients with high-RiskScores had the worse prognoses. RiskScores led to differences in gene mutation characteristics, antitumor drug sensitivity, and tumor microenvironment of CRC. A nomogram based on the signature was developed to predict the one-, three-, and five-year survival of CRC patients.

CONCLUSION

MAC-related genes were able to classify CRC. A RiskScore signature based on the colorectal MAC-related molecular subtype was constructed, which had important clinical significance for guiding the accurate stratification of CRC patients.

Rebuilding the microenvironment of primary tumors in humans: a focus on stroma

Conventional tumor models have critical shortcomings in that they lack the complexity of the human stroma. The heterogeneous stroma is a central compartment of the tumor microenvironment (TME) that must be addressed in cancer research and precision medicine. To fully model the human tumor stroma, the deconstruction and reconstruction of tumor tissues have been suggested as new approaches for in vitro tumor modeling. In this review, we summarize the heterogeneity of tumor-associated stromal cells and general deconstruction approaches used to isolate patient-specific stromal cells from tumor tissue; we also address the effect of the deconstruction procedure on the characteristics of primary cells. Finally, perspectives on the future of reconstructed tumor models are discussed, with an emphasis on the essential prerequisites for developing authentic humanized tumor models.

Expanded Alternatives of CRISPR-Cas9 Applications in Immunotherapy of Colorectal Cancer

Immunotherapy for colorectal cancer (CRC) is limited to patients with advanced disease who have already undergone first-line chemotherapy and whose tumors exhibit microsatellite instability. Novel technical strategies are required to enhance therapeutic options and achieve a more robust immunological response. Therefore, exploring gene analysis and manipulation at the molecular level can further accelerate the development of advanced technologies to address these challenges. The emergence of advanced genome editing technology, particularly of clustered, regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein (Cas) 9, holds promise in expanding the boundaries of cancer immunotherapy. In this manuscript, we provide a comprehensive review of the applications and perspectives of CRISPR technology in improving the design, generation, and efficiency of current immunotherapies, focusing on solid tumors such as colorectal cancer, where these approaches have not been as successful as in hematological conditions.

Immuno-oncologic signature of malignant transformation in oral squamous cell carcinoma

OBJECTIVE

The purpose of this study is to identify the immuno-oncologic (IO) signature at the surgical tumor margin (TM) of oral squamous cell carcinoma (OSCC) that is involved in the process of malignant transformation.

STUDY DESIGN

Under institutional review board approval, TM of 73 OSCC were investigated using immunohistochemistry for the immune biomarker, programmed death ligand-1 (PD-L1). NanoString 770 IO-focused gene set was analyzed in 5 pairs of TM and invasive tumor (T). PD-L1 regulation in response to interferon-gamma (IFN-γ) was investigated in an oral potentially malignant cell line (OPMC).

RESULTS

Programmed death ligand-1 expression in the epithelial margin directly correlated with its expression in the underlying immune cells (P = .0082). Differential gene expression showed downregulation of PD-L1 and IFN-γ 6 gene signature in the TM relative to T pair.CD8 and macrophages were higher in TM. CNTFR, LYZ, C7, RORC, and FGF13 downregulation in T relative to TM. TDO2, ADAM12, MMP1, LAMC2, MB21D1, TYMP, OASL, COL5A1, exhausted_CD8, Tregs,and NK_CD56dim were upregulated in T relative to TM. Finally, IFN-γ induced upregulation of PD-L1 in the OPMC.

CONCLUSIONS

Our work suggests a role for IFN-γ in PD-L1 upregulation in OPMC and presents novel IO transcriptional signatures for frankly invasive OSCC relative to TM.

The value of basement membrane-associated genes in the prognosis and immune regulation of glioma

Gliomas have a high incidence rate in central nervous tumors. Although many breakthroughs have been made in the pathogenesis and treatment of glioma, the recurrence and metastasis rates of patients have not been improved based on the uniqueness of glioma. Glioma destroys the surrounding basement membrane (BM), leading to local infiltration, resulting in the corresponding clinical and neurological symptoms. Therefore, exploring the biological roles played by BM associated genes in glioma is particularly necessary for a comprehensive understanding of the biological processes of glioma and its treatment. Differential expression and univariate COX regression analyses were used to identify the basement membrane genes (BMGs) to be included in the model. LASSO regression was used to construct the BMG model. The Kaplan-Meier (KM) survival analysis model was used to assess the prognosis discrimination between training sets, validation sets, and clinical subgroups. Receiver-operating characteristic (ROC) analysis was used to test the prognostic efficacy of the model. Use calibration curves to verify the accuracy of nomograms. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and gene set enrichment analysis (GSEA) were used to analyze the function and pathway enrichment among the model groups. ESTIMATE and other 7 algorithms including CIBERSORT were used to evaluate the immune microenvironment. "pRRophetic" was used to evaluate drug sensitivity. This study demonstrated that high-risk genes (LAMB4, MMP1, MMP7) promote glioma progression and negatively correlate with patient prognosis. In the tumor microenvironment (TME), high-risk genes have increased scores of macrophages, neutrophils, immune checkpoints, chemokines, and chemokine receptors. This study suggests that BMGs, especially high-risk-related genes, are potential sites for glioma therapy, a new prospect for comprehensively understanding the molecular mechanism of glioma.

Role of tumor-associated macrophages in common digestive system malignant tumors

Many digestive system malignant tumors are characterized by high incidence and mortality rate. Increasing evidence has revealed that the tumor microenvironment (TME) is involved in cancer initiation and tumor progression. Tumor-associated macrophages (TAMs) are a predominant constituent of the TME, and participate in the regulation of various biological behaviors and influence the prognosis of digestive system cancer. TAMs can be mainly classified into the antitumor M1 phenotype and protumor M2 phenotype. The latter especially are crucial drivers of tumor invasion, growth, angiogenesis, metastasis, immunosuppression, and resistance to therapy. TAMs are of importance in the occurrence, development, diagnosis, prognosis, and treatment of common digestive system malignant tumors. In this review, we summarize the role of TAMs in common digestive system malignant tumors, including esophageal, gastric, colorectal, pancreatic and liver cancers. How TAMs promote the development of tumors, and how they act as potential therapeutic targets and their clinical applications are also described.

The effects of MYC on tumor immunity and immunotherapy

The oncogene MYC is dysregulated in a host of human cancers, and as an important point of convergence in multitudinous oncogenic signaling pathways, it plays a crucial role in tumor immune regulation in the tumor immune microenvironment (TIME). Specifically, MYC promotes the expression of immunosuppressive factors and inhibits the expression of immune activation regulators. Undoubtedly, a therapeutic strategy that targets MYC can initiate a new era of cancer treatment. In this review, we summarize the essential role of the MYC signaling pathway in tumor immunity and the development status of MYC-related therapies, including therapeutic strategies targeting MYC and combined MYC-based immunotherapy. These studies have reported extraordinary insights into the translational application of MYC in cancer treatment and are conducive to the emergence of more effective immunotherapies for cancer.

Identification of novel characteristic biomarkers and immune infiltration profile for the anaplastic thyroid cancer via machine learning algorithms

PURPOSE

Anaplastic thyroid cancer (ATC) is a rare and lethal malignant cancer. In recent years, the application of molecular-driven targeted therapy and immunotherapy has markedly improved the prognosis of ATC. This study aimed to identify characteristic genes for ATC diagnosis and revealed the role of ATC characteristic genes in drug sensitivity and immune cell infiltration.

METHODS

We downloaded ATC RNA-sequencing data from the GEO database. Following the combination and normalization of the dataset, we first divided the combined datasets into the training cohort and the validation cohort. We identified differentially expressed genes (DEGs) in ATC by differential expression analysis in the training cohort. We used two machine learning algorithms, least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) to identify ATC characteristic genes. The CIBERSORT algorithm was performed to calculate the abundance of various immune cells in ATC. Finally, we validated the expression of ATC characteristic genes by quantitative RT-PCR (RT-qPCR) in ATC cell lines and immunohistochemistry (IHC).

RESULTS

A total of 425 DEGs were identified in the training cohort, including 240 upregulated genes and 185 downregulated genes. Four ATC characteristic genes (ADM, PXDN, MMP1, and TFF3) were identified, and their diagnostic value was validated in the validation cohort (AUC in ROC analysis > 0.75). We established a practical gene expression-based nomogram to accurately predict the probability of ATC. We also found that ATC characteristic biomarkers are associated with the tumor immune microenvironment and drug sensitivity.

CONCLUSION

ADM, PXDN, MMP1, and TFF3 might serve as potential ATC diagnostic biomarkers and may be helpful for ATC molecular targeted therapy and immunotherapy.

A pan-cancer analysis of the prognostic and immunological roles of matrix metalloprotease-1 (MMP1) in human tumors

Objective

Cancer remains the leading killer of human health worldwide. It has been shown that matrix metalloproteinase-1(MMP1) is related to poor prognosis in cancers such as BRCA, CESC and COAD. However, systematic pan-cancer analysis about the prognostic and immunological roles of MMP1 has not been explored. Here, the purpose of this study was to investigate the prognostic and immunological roles of MMP1 in pan-cancer and confirm cancer-promoting effect in pancreatic cancer.

Methods

In our study, bioinformatics were first used to analyze data from multiple databases. Then, several bioinformatics tools were utilized to investigate the role of MMP1 in 33 tumor types. Finally, molecular biology experiments were carried out to prove the cancer-promoting effect of MMP1 in pancreatic cancer.

Results

MMP1 expression was higher in tumor tissues than in control tissues in most tumor types. High expression of MMP1 was associated with poor overall survival (OS) and disease-free survival (DFS) in some tumor types. Further analysis of MMP1 gene mutation data showed that MMP1 mutations significantly influenced the prognosis of STAD. In addition, MMP1 expression was closely related to cancer-associated fibroblast (CAFs) infiltration in a variety of cancers and played an important role on immune infiltration score, tumor mutational burden (TMB) and microsatellite instability (MSI). Gene Ontology enrichment analysis indicated that these 20 genes were mainly related to extracellular structure organization/extracellular matrix organization/extracellular matrix disassembly/collagen metabolic process in the enriched biological processes. Finally, molecular biology experiments confirmed the cancer-promoting effect of MMP1 in pancreatic cancer.

Conclusions

Our pan-cancer analysis comprehensively proved that MMP1 expression is related with clinical prognosis and tumor immune infiltration, and MMP1 can become a prognostic and immunological biomarker.

Macrophages as a Potential Immunotherapeutic Target in Solid Cancers

The revolution in cancer immunotherapy over the last few decades has resulted in a paradigm shift in the clinical care of cancer. Most of the cancer immunotherapeutic regimens approved so far have relied on modulating the adaptive immune system. In recent years, strategies and approaches targeting the components of innate immunity have become widely recognized for their efficacy in targeting solid cancers. Macrophages are effector cells of the innate immune system, which can play a crucial role in the generation of anti-tumor immunity through their ability to phagocytose cancer cells and present tumor antigens to the cells of adaptive immunity. However, the macrophages that are recruited to the tumor microenvironment predominantly play pro-tumorigenic roles. Several strategies targeting pro-tumorigenic functions and harnessing the anti-tumorigenic properties of macrophages have shown promising results in preclinical studies, and a few of them have also advanced to clinical trials. In this review, we present a comprehensive overview of the pathobiology of TAMs and their role in the progression of solid malignancies. We discuss various mechanisms through which TAMs promote tumor progression, such as inflammation, genomic instability, tumor growth, cancer stem cell formation, angiogenesis, EMT and metastasis, tissue remodeling, and immunosuppression, etc. In addition, we also discuss potential therapeutic strategies for targeting TAMs and explore how macrophages can be used as a tool for next-generation immunotherapy for the treatment of solid malignancies.

ZNF3 regulates proliferation, migration and invasion through MMP1 and TWIST in colorectal cancer

Colorectal cancer (CRC) is a malignant tumor with a high incidence and mortality worldwide. Currently, the underlying molecular mechanisms of CRC are still unclear. Zinc finger protein 3 (ZNF3) is a zinc-finger transcription factor that has been reported as a candidate for breast cancer prognosis, suggesting its involvement in the regulation of tumorigenesis. However, the association between ZNF3 and CRC remains unknown. To investigate the role of ZNF3 in CRC, we first analyze the correlation between ZNF3 expression and CRC, and the results demonstrate that ZNF3 is highly expressed in CRC tissue and cells, which is associated with the age of CRC patients. In vitro studies show that ZNF3 overexpression promotes CRC cell migration. Compared to control cells, knockdown of ZNF3 markedly suppresses CRC cell proliferation, migration and invasion and promotes G0/G1 phase cell cycle arrest. The expressions of the EMT-related markers TWIST and MMP1 are significantly decreased when ZNF3 is silenced. Additionally, overexpression of MMP1 and TWIST exacerbates CRC cell proliferation, accelerates the S phase cell cycle in ZNF3-knockdown SW480 cells, and increases cell migration and invasion through Transwell chambers. These data suggest that ZNF3 is involved in cellular proliferation, migration and invasion by regulating MMP1 and TWIST in CRC cells.

The role of hypoxia-related genes in TACE-refractory hepatocellular carcinoma: Exploration of prognosis, immunological characteristics and drug resistance based on onco-multi-OMICS approach

Transcatheter arterial chemoembolization (TACE) is an effective treatment for hepatocellular carcinoma (HCC). During TACE, chemotherapeutic agents are locally infused into the tumor and simultaneously cause hypoxia in tumor cells. Importantly, the poor effect of TACE in some HCC patients has been shown to be related to dysregulated expression of hypoxia-related genes (HRGs). Therefore, we identified 33 HRGs associated with TACE (HRGTs) by differential analysis and characterized the mutational landscape of HRGTs. Among 586 HCC patients, two molecular subtypes reflecting survival status were identified by consistent clustering analysis based on 24 prognosis-associated HRGs. Comparing the transcriptomic difference of the above molecular subtypes, three molecular subtypes that could reflect changes in the immune microenvironment were then identified. Ultimately, four HRGTs (CTSO, MMP1, SPP1, TPX2) were identified based on machine learning approachs. Importantly, risk assessment can be performed for each patient by these genes. Based on the parameters of the risk model, we determined that high-risk patients have a more active immune microenvironment, indicating “hot tumor” status. And the Tumor Immune Dysfunction and Exclusion (TIDE), the Cancer Immunome Atlas (TCIA), and Genome of Drug Sensitivity in Cancer (GDSC) databases further demonstrated that high-risk patients have a positive response to immunotherapy and have lower IC50 values for drugs targeting cell cycle, PI3K/mTOR, WNT, and RTK related signaling pathways. Finally, single-cell level analysis revealed significant overexpression of CTSO, MMP1, SPP1, and TPX2 in malignant cell after PD-L1/CTLA-4 treatment. In conclusion, Onco-Multi-OMICS analysis showed that HRGs are potential biomarkers for patients with refractory TACE, and it provides a novel immunological perspective for developing personalized therapies.

MMP1 Overexpression Promotes Cancer Progression and Associates with Poor Outcome in Head and Neck Carcinoma

Matrix metalloproteinase-1 (MMP1) has been reported to play key roles in a variety of cancers by degrading the extracellular matrix. However, its carcinogenic roles have not been shown yet in head and neck squamous cell carcinoma (HNSCC). This study aimed to elucidate its expression pattern and functional roles as well as clinical significance in HNSCC. The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and immunohistochemistry (IHC) were utilized to determine the MMP1 expression pattern and the associations between its expression and patients' outcome in HNSCC. Mice tongue squamous cell carcinoma model induced by 4-nitroquinoline 1-oxide (4NQO) and siRNA-mediated cellular assay in vitro were utilized to evaluate the oncogenic role of MMP1. The biological functions and cancer-related pathways involved in MMP1-related genes were found through bioinformatics analysis. Both mRNA and protein abundance of MMP1 were highly increased in HNSCC as compared to its non-tumor counterparts. MMP1 overexpression positively correlated with advanced tumor size, cervical node metastasis, and advanced pathological grade and lower patients' survival. In the 4NQO-induced animal model, MMP1 expression increased along with the progression of the disease. In HNSCC cells, siRNA-mediated knockdown of MMP1 significantly inhibited cell proliferation, migration, and invasion and activated apoptosis and epithelia-mesenchymal transition (EMT). GSEA, GO, and KEGG analyses showed that MMP1 expression was significantly related to cancer-related pathways and cancer-related functions. Together, our results demonstrated MMP1 serves as a novel prognostic biomarker and putative oncogene in HNSCC.

Technique integration of single-cell RNA sequencing with spatially resolved transcriptomics in the tumor microenvironment

Background

The tumor microenvironment contributes to tumor initiation, growth, invasion, and metastasis. The tumor microenvironment is heterogeneous in cellular and acellular components, particularly structural features and their gene expression at the inter-and intra-tumor levels.

Main text

Single-cell RNA sequencing profiles single-cell transcriptomes to reveal cell proportions and trajectories while spatial information is lacking. Spatially resolved transcriptomics redeems this lack with limited coverage or depth of transcripts. Hence, the integration of single-cell RNA sequencing and spatial data makes the best use of their strengths, having insights into exploring diverse tissue architectures and interactions in a complicated network. We review applications of integrating the two methods, especially in cellular components in the tumor microenvironment, showing each role in cancer initiation and progression, which provides clinical relevance in prognosis, optimal treatment, and potential therapeutic targets.

Conclusion

The integration of two approaches may break the bottlenecks in the spatial resolution of neighboring cell subpopulations in cancer, and help to describe the signaling circuitry about the intercommunication and its exact mechanisms in producing different types and malignant stages of tumors.

Role of macrophages in cancer progression and targeted immunotherapies

The vast complexity of the tumor microenvironment (TME) aggrandizes the underlying principles responsible for immune escape, therapy resistance, and treatment failure. The stromal and immune cell population circumjacent to the tumor cells affects the cancer cell cycle leading to tumor progression. Tumor-associated macrophages (TAMs) exhibiting a unique M2 polarization state constitute a significant portion of the TME. They serve as tumor suppressors at early stages and tumor promoters at advanced stages by governing various microenvironmental cues. TAMs secreted various pro-tumoral cytokines, chemokines, and matrix metalloproteases are known to regulate the different cell cycle molecules including checkpoint inhibitors in cancer cells leading to cell cycle progression with faulty cellular components. Moreover, TAMs are well-known immunosuppressors and thereby facilitating the tumor cells' evasion from immune recognition. This chapter will describe the interaction between TAMs and tumor cells, the involvement of TAMs in the regulation of cancer cell progression by controlling cell cycle checkpoints or molecular pathways, and current TAM-based therapies, including restriction of TAM recruitment, anti-survival strategies, or switching polarity. Moreover, this chapter will also emphasize recently developed drug targets and CAR-macrophage cell therapy that restricts tumor progression.