Integrative analysis of bulk and single-cell gene expression profiles to identify tumor-associated macrophage-derived CCL18 as a therapeutic target of esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a common gastrointestinal malignancy with poor patient prognosis. Current treatment for ESCC, including immunotherapy, is only beneficial for a small subset of patients. Better characterization of the tumor microenvironment (TME) and the development of novel therapeutic targets are urgently needed. METHODS: In the present study, we hypothesized that integration of single-cell transcriptomic sequencing and large microarray sequencing of ESCC biopsies would reveal the key cell subtypes and therapeutic targets that determine the prognostic and tumorigenesis of ESCC. We characterized the gene expression profiles, gene sets enrichment, and the TME landscape of a microarray cohort including 84 ESCC tumors and their paired peritumor samples. We integrated single-cell transcriptomic sequencing and bulk microarray sequencing of ESCC to reveal key cell subtypes and druggable targets that determine the prognostic and tumorigenesis of ESCC. We then designed and screened a blocking peptide targeting Chemokine C-C motif ligand 18 (CCL18) derived from tumor associated macrophages and validated its potency by MTT assay. The antitumor activity of CCL18 blocking peptide was validated in vivo by using 4-nitroquinoline-1-oxide (4-NQO) induced spontaneous ESCC mouse model. RESULTS: Comparative gene expression and cell-cell interaction analyses revealed dysregulated chemokine and cytokine pathways during ESCC carcinogenesis. TME deconvolution and cell interaction analyses allow us to identify the chemokine CCL18 secreted by tumor associated macrophages could promote tumor cell proliferation via JAK2/STAT3 signaling pathway and lead to poor prognosis of ESCC. The peptide Pep3 could inhibit the proliferation of EC-109 cells promoted by CCL18 and significantly restrain the tumor progression in 4-NQO-induced spontaneous ESCC mouse model. CONCLUSIONS: For the first time, we discovered and validated that CCL18 blockade could significantly prevent ESCC progression. Our study revealed the comprehensive cell-cell interaction network in the TME of ESCC and provided novel therapeutic targets and strategies to ESCC treatment.

Controlling porous titanium/soft tissue interactions with an innovative surface chemical treatment: Responses of macrophages and fibroblasts.

In order to create a stable interface with the host tissue, porous implants are widely used to ensure the in-growth of the cells and the colonization of the implant. An ideal porous implant should have a 3D architecture that enables fast migration of incoming cells while not inducing a significant pro-inflammatory response by the immune cells. Moreover, in patients where the healing is impeded (patients with co-morbidities and metabolic diseases), porosity by itself is not enough for fast colonization, and the surface properties of the implant should also be controlled. In this study, we present a controlled oxidation-based surface treatment of microbead-based porous titanium implants which not only increases the colonization by connective tissue cells but also decreases the macrophage attachment. The treatment created a nanotextured surface on the implants with an acidic shift of isoelectric point (from 4.09 to 3.09) without endangering implant's mechanical integrity. The attachment and metabolic activity of activated macrophages were significantly lower on treated surfaces with an increase in the secretion of anti-inflammatory IL-1RA and a decrease in pro-fibrotic CCL-18. Human fibroblasts proliferated faster on the treated surfaces over 14 days with near complete colonization of the whole thickness of the implant with an accompanying an increase in the secretion of TGF-beta. The surface treated samples demonstrated partial filling of the entire pores. We demonstrated that the use of nanoscale surface treatments that can be applied to the whole internal surface of porous titanium implants can significantly alter both the immune response and the colonization of the implants and can be used to fine-tune and personalize implant interfaces according to patient needs.

Interleukin-32θ inhibits tumor-promoting effects of macrophage-secreted CCL18 in breast cancer.

BACKGROUND: Tumor-associated macrophages can promote breast cancer metastasis by secreting cytokines and growth factors. Interleukin (IL)-32θ, a newly identified IL-32 isoform, was previously shown to down-regulate various proinflammatory factors of macrophages. Here, we report the presence of IL-32θ in breast cancer tissues and evaluate its effects on macrophage-regulated breast cancer metastasis. METHODS: RT-qPCR was used to analyze the mRNA expression of IL-32θ, Chemokine (C-C motif) ligand 18 (CCL18) in breast cancer tissues. In vitro cell-based experiments using IL-32θ-expressing MDA-MB-231 cells were conducted to examine the effects of IL-32θ on metastasis and its molecular signaling. In vivo xenograft, immunohistochemistry, and optical imaging models were generated to support in vitro and clinical findings. RESULTS: The clinical data displayed opposite expression patterns of CCL18 and IL-32θ mRNA in macrophage-infiltrated breast tumor tissues compared with those in the other tissues tested. In MDA-MB-231 cells, IL-32θ overexpression attenuated migration, invasion, tumor-promoting factors, and increased epithelial markers levels upon treatment with conditioned media from THP-1-derived macrophages. Additionally, IL-32θ expression in a xenograft model led to a remarkable decrease in tumor size and macrophage-stimulated tumor promotion. This inhibition was mediated through a direct interaction with protein kinase C-δ (PKCδ), subsequently eliminating the downstream factors STAT3 and NF-κB. Blocking CCL18 during co-culture of macrophages and breast cancer cells reduced the levels of breast cancer progression-related factors and PKCδ downstream signaling suggesting CCL18 as the main macrophage-secreted factors triggering the signaling pathway inhibited by IL-32θ. CONCLUSIONS: Our findings demonstrate a novel role of IL-32θ as an intracellular modulator to suppress macrophage-promoted breast cancer progression by targeting CCL18-dependent signaling.