Extracellular vesicles promote activation of pro-inflammatory cancer-associated fibroblasts in oral cancer

Plasma-Derived Extracellular Vesicles and Non-Extracellular Vesicle Components from APCMin/+ Mice Promote Pro-Tumorigenic Activities and Activate Human Colonic Fibroblasts via the NF-κB Signaling Pathway

Colorectal cancer (CRC) is the third most prevalent cancer worldwide. Current studies have demonstrated that tumor-derived extracellular vesicles (EVs) from different cancer cell types modulate the fibroblast microenvironment to contribute to cancer development and progression. Here, we isolated and characterized circulating large EVs (LEVs), small EVs (SEVs) and non-EV entities released in the plasma from wild-type (WT) mice and the APCMin/+ CRC mice model. Our results showed that human colon fibroblasts exposed from APC-EVs, but not from WT-EVs, exhibited the phenotypes of cancer-associated fibroblasts (CAFs) through EV-mediated NF-κB pathway activation. Cytokine array analysis on secreted proteins revealed elevated levels of inflammatory cytokine implicated in cancer growth and metastasis. Finally, non-activated cells co-cultured with supernatant from fibroblasts treated with APC-EVs showed increased mRNA expressions of CAFs markers, the ECM, inflammatory cytokines, as well as the expression of genes controlled by NF-κB. Altogether, our work suggests that EVs and non-EV components from APCMin/+ mice are endowed with pro-tumorigenic activities and promoted inflammation and a CAF-like state by triggering NF-κB signaling in fibroblasts to support CRC growth and progression. These findings provide insight into the interaction between plasma-derived EVs and human cells and can be used to design new CRC diagnosis and prognosis tools.

FOXD2-AS1 promotes malignant cell behavior in oral squamous cell carcinoma via the miR-378 g/CRABP2 axis

BACKGROUND

Oral squamous cell cancer (OSCC) is a prevalent malignancy in oral cavity, accounting for nearly 90% of oral malignancies. It ranks sixth among the most common types of cancer worldwide and is responsible for approximately 145,000 deaths each year. It is widely accepted that noncoding RNAs participate cancer development in competitive regulatory interaction, knowing as competing endogenous RNA (ceRNA) network, whereby long non-coding RNA (lncRNA) function as decoys of microRNAs to regulate gene expression. LncRNA FOXD2-AS1 was reported to exert an oncogenic role in OSCC. Nevertheless, the ceRNA network mediated by FOXD2-AS1 was not investigated yet. This study aimed to explore the effect of FOXD2-AS1 on OSCC cell process and the underlying ceRNA mechanism.

METHODS

FOXD2-AS1 expression in OSCC cells were determined via reverse transcription and quantitative polymerase chain reaction. Short hairpin RNA targeting FOXD2-AS1 was transfected into OSCC cells to silence FOXD2-AS1 expression. Then, loss-of-function experiments (n = 3 each assay) were performed to measure cell proliferation, apoptosis, migration, and invasion using colony formation, TdT-mediated dUTP Nick-End Labeling, wound healing and Transwell assays, respectively. RNA binding relation was verified by RNA immunoprecipitation and luciferase reporter assays. Rescue experiments were designed to validate whether FOXD2-AS1 affects cell behavior via the gene cellular retinoic acid binding protein 2 (CRABP2). Statistics were processed by GraphPad Prism 6.0 Software and SPSS software.

RESULTS

FOXD2-AS1 was significantly upregulated in Cal27 and SCC9 cells (6.8 and 6.4 folds). In response to FOXD2-AS1 knockout, OSCC cell proliferation, migration and invasion were suppressed (approximately 50% decrease) while OSCC cell apoptosis was enhanced (more than two-fold increase). FOXD2-AS1 interacted with miR-378 g to alter CRABP2 expression. CRABP2 upregulation partly rescued (*p < 0.05, **p < 0.01, ***p < 0.001) the inhibitory impact of FOXD2-AS1 depletion on malignant characteristics of OSCC cells.

CONCLUSION

FOXD2-AS1 enhances OSCC malignant cell behaviors by interacting with miR-378 g to regulate CRABP2 expression.

Extracellular vesicles as tools and targets in therapy for diseases

Extracellular vesicles (EVs) are nano-sized, membranous structures secreted into the extracellular space. They exhibit diverse sizes, contents, and surface markers and are ubiquitously released from cells under normal and pathological conditions. Human serum is a rich source of these EVs, though their isolation from serum proteins and non-EV lipid particles poses challenges. These vesicles transport various cellular components such as proteins, mRNAs, miRNAs, DNA, and lipids across distances, influencing numerous physiological and pathological events, including those within the tumor microenvironment (TME). Their pivotal roles in cellular communication make EVs promising candidates for therapeutic agents, drug delivery systems, and disease biomarkers. Especially in cancer diagnostics, EV detection can pave the way for early identification and offers potential as diagnostic biomarkers. Moreover, various EV subtypes are emerging as targeted drug delivery tools, highlighting their potential clinical significance. The need for non-invasive biomarkers to monitor biological processes for diagnostic and therapeutic purposes remains unfulfilled. Tapping into the unique composition of EVs could unlock advanced diagnostic and therapeutic avenues in the future. In this review, we discuss in detail the roles of EVs across various conditions, including cancers (encompassing head and neck, lung, gastric, breast, and hepatocellular carcinoma), neurodegenerative disorders, diabetes, viral infections, autoimmune and renal diseases, emphasizing the potential advancements in molecular diagnostics and drug delivery.

Cancer-Associated Fibroblast Heterogeneity in Malignancy with Focus on Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) remains an understudied and significant global cancer killer and dismal survival rates have not changed in decades. A better understanding of the molecular basis of OSCC progression and metastasis is needed to develop new approaches for treating this disease. The supportive network surrounding cancer tumor cells known as the tumor microenvironment (TME) has gained increasing interest lately since it performs essential protumorigenic functions. Cancer-associated fibroblasts (CAFs) are one of the main cell types in the TME and are known to play a key role in influencing the biological behavior of tumors. CAFs present a heterogeneity both in phenotype as well as functions, leading to the suggestion of different CAF subtypes in several cancer forms. The task to subtype CAFs in OSCC has, however, just begun, and there is today no united way of subtyping CAFs in this disease. This review aims to define the features of CAFs and to summarize CAF subtype research in malignancy with focus on OSCC including aspects as disease prognosis and therapeutic opportunities.