Tumor-associated macrophages in lung carcinoma: From mechanism to therapy

CASQ2 alleviates lung cancer by inhibiting M2 tumor-associated macrophage polarization and JAK/STAT pathway

Lung cancer (LC) is a major inducer of cancer-related death. We aim to reveal the effect of Calsequestrin2 (CASQ2) on macrophage polarization and Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway in LC. Hub genes were determined from protein-protein interaction networks based on GSE21933 and GSE1987 data sets using bioinformatic analysis. Expression of hub genes was verified by real-time quantitative polymerase chain reaction (RT-qPCR). Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine, wound-healing, colony formation, and transwell assays were performed to assess the impact of CASQ2 on LC cells. A xenograft mouse model was evaluated using hematoxylin-eosin, immunohistochemistry, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining to investigate the effect of CASQ2 on LC. The role of CASQ2 in regulating macrophage polarization and JAK/STAT pathway was evaluated by western blot andRT-qPCR. We screened out 155 common differentially expressed genes in GSE21933 and GSE1987 data sets. Myomesin-2, tyrosine kinase, sex determining region Y-box 2, platelet and endothelial cell adhesion molecule 1, matrix metallopeptidase 9, claudin-5, caveolin-1, CASQ2, recombinant ATPase, Ca++ transporting, cardiac muscle, slow twitch 2 (ATP2A2), and ankyrin repeat domain 1 were identified as the hub genes with high prediction value. CASQ2 was selected as a pivotal regulator of LC. In vitro experiments and xenograft models revealed that CASQ2 overexpression suppressed proliferation, colony formation, migration, invasion of LC cells, and tumor growth in vivo. Additionally, overexpression of CASQ2 promoted the expression of M1 macrophage markers (cluster of differentiation 80 [CD80], interleukin [IL]-12, inducible nitric oxide synthase [iNOS]), while decreasing the expression of M2 macrophage markers (CD163, IL-10, Arg1) in tumor-associated macrophages and xenograft tissues. Finally, we found that overexpression of CASQ2 inhibited JAK/STAT pathway. CASQ2 is a novel biomarker, which can alleviate LC via inhibiting M2 tumor-associated macrophage polarization and JAK/STAT pathway.

UBA5 inhibition restricts lung adenocarcinoma via blocking macrophage M2 polarization and cisplatin resistance

UBA5, a ubiquitin-like activated enzyme involved in ufmylation and sumoylation, presents a viable target for pancreatic and breast cancer treatments, yet its role in lung adenocarcinoma (LUAD) remains underexplored. This study reveals UBA5's tumor-promoting effect in LUAD, as evidenced by its upregulation in patients and positive correlation with TNM stages. Elevated UBA5 levels predict poor outcomes for these patients. Pharmacological inhibition of UBA5 using DKM 2-93 significantly curtails the growth of A549, H1299, and cisplatin-resistant A549 (A549/DDP) LUAD cells in vitro. Additionally, UBA5 knockdown via shRNA lentivirus suppresses tumor growth both in vitro and in vivo. High UBA5 expression adversely alters the tumor immune microenvironment, affecting immunostimulators, MHC molecules, chemokines, receptors, and immune cell infiltration. Notably, UBA5 expression correlates positively with M2 macrophage infiltration, the predominant immune cells in LUAD. Co-culture experiments further demonstrate that UBA5 knockdown directly inhibits M2 macrophage polarization and lactate production in LUAD. Moreover, in vivo studies show reduced M2 macrophage infiltration following UBA5 knockdown. UBA5 expression is also associated with increased tumor heterogeneity, including tumor mutational burden, microsatellite instability, neoantigen presence, and homologous recombination deficiency. Experiments indicate that UBA5 overexpression promotes cisplatin resistance in vitro, whereas UBA5 inhibition enhances cisplatin sensitivity in both in vitro and in vivo settings. Overall, these findings suggest that targeting UBA5 inhibits LUAD by impeding cancer cell proliferation, M2 macrophage polarization, and cisplatin resistance.

Cellular Distribution and Intracellular Localization of Different Sizes of Fluorescent Thiol-Organosilica Particles in Mouse Lungs

We investigated the distribution of intratracheally administered thiol-organosilica (thiol-OS) particles in mouse lungs. Toward this end, single doses of thiol-OS particles containing fluorescein (140 nm in diameter) (F140) and rhodamine B (Rh) (Rh160, Rh280, Rh420, Rh640, and Rh1630 with diameters of 160, 280, 420, 640, and 1630 nm, respectively) were administered. After 24 h, fluorescence imaging revealed homogeneous fluorescence with a patchier pattern on the lung surface and no difference among the six particle sizes. Simultaneous dual administration of Rh and F140 particles did not reveal any size-dependent differences in the lung surface fluorescence. Fluorescence microscopy of the lung sections revealed a similar tissue distribution in the fluorescent areas of Rhs and F140. Some fluorescent areas showed one type of particle fluorescence or only one fluorescence. Cellular distribution of particles was observed in bronchoalveolar lavage cells and lung sections under a high magnification, and correlative light and electron microscopy revealed large cells with fluorescence corresponding to both particle types and small cells with fluorescence of individual particle types, indicating a cell-subset-dependent particle size effect. Rh280, Rh420, and Rh640 exhibited significant size effects and were taken up by alveolar macrophages. Extracellular particles were observed, indicating that saturation exceeded the particle dose threshold in the alveoli. F140 taken up by small and large macrophages colocalized with CD68, CD11c, and CD11b and correlated with CD11c. The size effect, intracellular localization, and extracellular distribution of particles provide insights into lung and systemic drug delivery.

Prenatal inflammation exposure accelerates lung cancer tumorigenesis in offspring mouse: possible links to IRE1α/XBP1-mediated M2-like polarization of TAMs and PD-L1 up-expression

BACKGROUND

Prenatal inflammation exposure (PIE) can increase the disease susceptibility in offspring such as lung cancer. Our purpose was to investigate the mechanisms of PIE on lung cancer.

METHODS

Prenatal BALB/c mice were exposed to lipopolysaccharide (LPS), and then, their offspring were intraperitoneally instilled with urethane to establish the two-stage lung cancer carcinogenesis model. At the 48 weeks of age, the offspring mice were killed and lung tissues were collected for HE, immunohistochemistry, immunofluorescence, and Luminex MAGPIX®-based assays. CD11b + F4/80 + tumor-associated macrophages (TAMs) were sorted out from lung tumor tissues by cell sorting technique. Flow cytometry was employed to evaluate the extent of M2-like polarization of TAMs and PD-L1 expression.

RESULTS

The offspring of PIE mice revealed more lung lesion changes, including atypical hyperplasia and intrapulmonary metastases. The number of lung nodules, lung organ index, and PCNA, MMP-9 and Vimentin positive cells in lung tissue of PIE group were higher than those of Control group. The increases of mRNA encoding M2 macrophage markers and cytokines in offspring of prenatal LPS-treated mice confirmed the induced effect of PIE on macrophage polarization. Additionally, PIE treatment increased the percentage of CD163 + CD206 + cells in the sorted TAMs. Importantly, endoplasmic reticulum (ER) stress-markers like GRP78/BIP and CHOP, p-IRE1α and XBP1s, and PD-L1 were up-regulated in TAMs from PIE group. Besides, we also observed that IRE1α inhibitor (KIRA6) reversed the M2-like TAMs polarization and metastasis induced by PIE.

CONCLUSIONS

IRE1α/XBP1-mediated M2-like TAMs polarization releases the pro-tumorigenic cytokines and PD-L1 expression, which may be the regulatory mechanism of accelerating lung cancer in offspring of mice undergoing PIE.

TRIM65 knockout inhibits the development of HCC by polarization tumor-associated macrophages towards M1 phenotype via JAK1/STAT1 signaling pathway

BACKGROUND & AIMS

Tumor-associated macrophages (TAMs) are main components of immune cells in tumor microenvironment (TME), and play a crucial role in tumor progression. Tripartite motif-containing protein 65 (TRIM65) has been associated with tumor progression. However, whether TRIM65 regulate the interaction of tumor cell and TAMs in HCC and the underlying mechanisms remain unknown. In this study, we investigated the role of TRIM65 in TME of HCC and explored its underlying mechanisms.

METHODS

The relation of TRIM65 expression level with tumor grades, TNM stages, and worse prognosis of HCC patients was evaluated by bioinformatics analysis, as well as immune infiltration level of macrophages. TRIM65 shRNA was transfected into HepG2 cells, and TRIM65 overexpression plasmid was transfected into Huh7 cells, and the effect of TRIM65 on cell growth was examined by EdU assay. The mouse subcutaneous Hep1-6 tumor-bearing model with WT and TRIM65-/- mice was established to study the role of TRIM65 in HCC. Immunohistochemistry staining, Immunofluorescence staining, qRT-PCR and western blot were performed to evaluate the effect of TRIM65 on TAM infiltration, TAM polarization and JAK1/STAT1 signaling pathway.

RESULTS

Bioinformatics analysis revealed that TRIM65 was upregulated in 16 types of cancer especially in HCC, and high level of TRIM65 was strongly correlated with higher tumor grades, TNM stages, and worse prognosis of patients with HCC as well as immune infiltration level of macrophages (M0, M1, and M2). Moreover, we observed that TRIM65 shRNA-mediated TRIM65 knockdown significantly inhibited the HepG2 cells growth while TRIM65 overexpression highly increased the Huh7 cells growth in vitro. TRIM65 knockout significantly inhibited the tumor growth as well as macrophages polarization towards M2 but promoted macrophages polarization towards M1 in vivo. Mechanistically, the results demonstrate that TRIM65 knockout promoted macrophage M1 polarization in conditioned medium-stimulated peritoneal macrophages and in tumor tissues by activating JAK1/STAT1 signaling pathway.

CONCLUSIONS

Taken together, our study suggests that tumor cells utilize TRIM65-JAK1/STAT1 axis to inhibit macrophage M1 polarization and promote tumor growth, reveals the role of TRIM65 in TAM-targeting tumor immunotherapy.

A Novel Cytochrome P450 2E1 Inhibitor Q11 Is Effective on Lung Cancer via Regulation of the Inflammatory Microenvironment

Lung cancer is the leading cause of death among all cancers. A persistent chronic inflammatory microenvironment is highly correlated with lung cancer. However, there are no anti-inflammatory agents effective against lung cancer. Cytochrome P450 2E1 (CYP2E1) plays an important role in the inflammatory response. Here, it is found that CYP2E1 is significantly higher in the peritumoral tissue of non-small cell lung cancer (NSCLC) patients and lung tumor growth is significantly impeded in Cyp2e1-/- mice. The novel CYP2E1 inhibitor Q11, 1-(4-methyl-5-thialzolyl) ethenone, is effective in the treatment of lung cancer in mice, which can inhibit cancer cells by changing macrophage polarization rather than directly act on the cancer cells. It is also clarify that the benefit of Q11 may associated with the IL-6/STAT3 and MAPK/ERK pathways. The data demonstrate that CYP2E1 may be a novel inflammatory target and that Q11 is effective on lung cancer by regulation of the inflammatory microenvironment. These findings provide a molecular basis for targeting CYP2E1 and illustrate the potential druggability of the CYP2E1 inhibitor Q11.

Tumor associated macrophages in esophageal squamous carcinoma: Promising therapeutic implications

Esophageal squamous carcinoma (ESCC) is a prevalent and highly lethal malignant tumor, with a five-year survival rate of approximately 20 %. Tumor-associated macrophages (TAMs) are the most prominent immune cells in the tumor microenvironment (TME), comprising over 50 % of the tumor volume. TAMs can be polarized into two distinct phenotypes, M1-type and M2-type, through interactions with cancer cells. M2-type TAMs are more abundant than M1-type TAMs in the TME, contributing to tumor progression, such as tumor cell survival and the construction of an immunosuppressive environment. This review focuses on the role of TAMs in ESCC, including their polarization, impact on tumor proliferation, angiogenesis, invasion, migration, therapy resistance, and immunosuppression. In addition, we discuss the potential of targeting TAMs for clinical therapy in ESCC. A thorough comprehension of the molecular biology about TAMs is essential for the development of innovative therapeutic strategies to treat ESCC.

Garcinone E suppresses breast cancer growth and metastasis by modulating tumor-associated macrophages polarization via STAT6 signaling

Cancer metastasis remains the most common cause of death in breast cancer patients. Tumor-associated macrophages (TAMs) are a novel therapeutic target for the treatment of metastatic breast cancer. Despite the good anti-cancer activity of garcinone E (GE), there are no reports on its therapeutic effects on breast cancer metastasis. The objective of this study was to examine the anti-cancer effects of GE on metastatic breast cancer. RAW 264.7 and THP-1 cells were polarized to M2 macrophages by IL-4/IL-13 in vitro. A 4T1 mouse breast cancer model and the tail vein breast cancer metastasis model were used to explore the effect of GE on breast cancer growth and metastasis in vivo. In vitro studies showed that GE dose-dependently suppressed IL-4 + IL-13-induced expression of CD206 in both RAW 264.7 cells and differentiated THP-1 macrophages. However, GE did not affect the LPS + IFN-γ-induced polarization to the M1-like macrophages in vitro. GE inhibited the expression of the M2 macrophage specific genes in RAW 264.7 cells, and simultaneously impaired M2 macrophage-induced breast cancer cell proliferation and migration, and angiogenesis. In animal studies, GE significantly suppressed tumor growth, angiogenesis, and lung metastasis in 4T1 tumor-bearing mice, without causing toxicity. In both tumor and lung tissues, the proportion of M2-like TAMs was significantly decreased while the proportion of M1-like TAMs was markedly increased by GE treatment. Mechanistically, GE inhibited phosphorylation of STAT6 in vitro and in vivo. Our results demonstrate for the first time that GE suppresses breast cancer growth and pulmonary metastasis by modulating M2-like macrophage polarization through the STAT6 signaling pathway.