NAB 2-Expressing Cancer-Associated Fibroblast Promotes HNSCC Progression

Engineering models of head and neck and oral cancers on-a-chip

Head and neck cancers (HNCs) rank as the sixth most common cancer globally and result in over 450 000 deaths annually. Despite considerable advancements in diagnostics and treatment, the 5-year survival rate for most types of HNCs remains below 50%. Poor prognoses are often attributed to tumor heterogeneity, drug resistance, and immunosuppression. These characteristics are difficult to replicate using in vitro or in vivo models, culminating in few effective approaches for early detection and therapeutic drug development. Organs-on-a-chip offer a promising avenue for studying HNCs, serving as microphysiological models that closely recapitulate the complexities of biological tissues within highly controllable microfluidic platforms. Such systems have gained interest as advanced experimental tools to investigate human pathophysiology and assess therapeutic efficacy, providing a deeper understanding of cancer pathophysiology. This review outlines current challenges and opportunities in replicating HNCs within microphysiological systems, focusing on mimicking the soft, glandular, and hard tissues of the head and neck. We further delve into the major applications of organ-on-a-chip models for HNCs, including fundamental research, drug discovery, translational approaches, and personalized medicine. This review emphasizes the integration of organs-on-a-chip into the repertoire of biological model systems available to researchers. This integration enables the exploration of unique aspects of HNCs, thereby accelerating discoveries with the potential to improve outcomes for HNC patients.

Cancer-associated fibroblasts: Mediators of head and neck tumor microenvironment remodeling

Cancer-associated fibroblasts (CAFs) are involved in critical aspects of head and neck squamous cell carcinoma (HNSCC) pathogenesis, such as the formation of a tumor-permissive extracellular matrix structure, angiogenesis, or immune and metabolic reprogramming of the tumor microenvironment (TME), with implications for metastasis and resistance to radiotherapy and chemotherapy. The pleiotropic effect of CAFs in TME is likely to reflect the heterogeneity and plasticity of their population, with context-dependent effects on carcinogenesis. The specific properties of CAFs provide many targetable molecules that could play an important role in the future therapy of HNSCC. In this review article, we will focus on the role of CAFs in the TME of HNSCC tumors. We will also discuss clinically relevant agents targeting CAFs, their signals, and signaling pathways, which are activated by CAFs in cancer cells, with the potential for repurposing for HNSCC therapy.

Cancer-associated fibroblasts: Origin, function, imaging, and therapeutic targeting

The tumor microenvironment (TME) is emerging as one of the primary barriers in cancer therapy. Cancer-associated fibroblasts (CAF) are a common inhabitant of the TME in several tumor types and play a critical role in tumor progression and drug resistance via different mechanisms such as desmoplasia, angiogenesis, immune modulation, and cancer metabolism. Due to their abundance and significance in pro-tumorigenic mechanisms, CAF are gaining attention as a diagnostic target as well as to improve the efficacy of cancer therapy by their modulation. In this review, we highlight existing imaging techniques that are used for the visualization of CAF and CAF-induced fibrosis and provide an overview of compounds that are known to modulate CAF activity. Subsequently, we also discuss CAF-targeted and CAF-modulating nanocarriers. Finally, our review addresses ongoing challenges and provides a glimpse into the prospects that can spearhead the transition of CAF-targeted therapies from opportunity to reality.

Signaling pathways in cancer-associated fibroblasts and targeted therapy for cancer

To flourish, cancers greatly depend on their surrounding tumor microenvironment (TME), and cancer-associated fibroblasts (CAFs) in TME are critical for cancer occurrence and progression because of their versatile roles in extracellular matrix remodeling, maintenance of stemness, blood vessel formation, modulation of tumor metabolism, immune response, and promotion of cancer cell proliferation, migration, invasion, and therapeutic resistance. CAFs are highly heterogeneous stromal cells and their crosstalk with cancer cells is mediated by a complex and intricate signaling network consisting of transforming growth factor-beta, phosphoinositide 3-kinase/AKT/mammalian target of rapamycin, mitogen-activated protein kinase, Wnt, Janus kinase/signal transducers and activators of transcription, epidermal growth factor receptor, Hippo, and nuclear factor kappa-light-chain-enhancer of activated B cells, etc., signaling pathways. These signals in CAFs exhibit their own special characteristics during the cancer progression and have the potential to be targeted for anticancer therapy. Therefore, a comprehensive understanding of these signaling cascades in interactions between cancer cells and CAFs is necessary to fully realize the pivotal roles of CAFs in cancers. Herein, in this review, we will summarize the enormous amounts of findings on the signals mediating crosstalk of CAFs with cancer cells and its related targets or trials. Further, we hypothesize three potential targeting strategies, including, namely, epithelial-mesenchymal common targets, sequential target perturbation, and crosstalk-directed signaling targets, paving the way for CAF-directed or host cell-directed antitumor therapy.

Tumor microenvironment in head and neck squamous cell carcinoma: Functions and regulatory mechanisms

The tumor microenvironment has been recently reported to play a pivotal role in sustaining tumor cells survival and protecting them from immunotherapy and chemotherapy-induced death. It remains largely unknown how the specific signaling pathway exerts the tumor microenvironment in head and neck squamous cell carcinoma though previous studies have elucidated the regulatory mechanisms involve in tumor immune microenvironment, stromal cells, tumor angiogenesis and cancer stem cell. These components are responsible for tumor progression as well as anti-cancer therapy resistance, leading to rapid tumor growth and treatment failure. In this review, we focus on discussing the interaction between tumor cells and the surrounding components for better understanding of anti-cancer treatment ineffectiveness and its underlying molecular mechanisms.

Regulation of the early growth response-1 binding protein NAB2 in bovine granulosa cells and effect on connective tissue growth factor expression

Ovarian fibrosis is associated with increased expression of the transcription factor, Early growth response-1 (EGR1) and connective tissue growth factor (CCN2) in granulosa cells. The transcriptional activity of EGR1 is under negative feedback control by NAB1 and NAB2, but little is known about NAB expression in granulosa cells. Using a well-defined bovine in-vitro granulosa cell model, we show that NAB2 but not NAB1 mRNA is upregulated by fibroblast growth factor (FGF)1 and FGF2, but not by FGF4 or FGF8b. Overexpressing NAB2 abrogated the ability of FGF8b to increase EGR1 and CCN2 mRNA, as well as mRNAs encoding other FGF-target genes. Surprisingly, overexpression of NAB2 in the absence of growth factor stimulation increased abundance of mRNA encoding CCN2 and EGR1, and decreased estradiol secretion. We conclude that NAB2 is expressed in granulosa cells and plays a role in regulating EGR1-induced CCN2 expression, although cross-talk with other signaling pathways is likely occurring.

The Immune Microenvironment in Head and Neck Squamous Cell Carcinoma: on Subsets and Subsites

PURPOSE

To understand why some patients respond to immunotherapy but many do not, a clear picture of the tumor microenvironment (TME) of head and neck squamous cell carcinoma (HNSCC) is key. Here we review the current understanding on the immune composition per HNSCC subsite, the importance of the tumor's etiology and the prognostic power of specific immune cells.

RECENT FINDINGS

Large cohort data are mostly based on deconvolution of transcriptional databases. Studies focusing on infiltrate localization often entail small cohorts, a mixture of HNSCC subsites, or focus on a single immune marker rather than the interaction between cells within the TME. Conclusions on the prognostic impact of specific immune cells in HNSCC are hampered by the use of heterogeneous or small cohorts. To move forward, the field should focus on deciphering the immune composition per HNSCC subsite, in powered cohorts and considering the molecular diversity in this disease.

Potential Salivary mRNA Biomarkers for Early Detection of Oral Cancer

We evaluated potential biomarkers in human whole saliva for the early diagnosis of oral squamous cell carcinoma (OSCC). We selected 30 candidate genes with relevance to cancer from recent reports in PubMed. Saliva samples were obtained from 34 non-tumor control and 33 OSCC patients. Real-time PCR was performed, and mRNA levels were compared. Normalized mRNA levels of six genes (NGFI-A binding protein 2 (NAB2), cytochrome P450, family 27, subfamily A, polypeptide 1 (CYP27A1), nuclear pore complex interacting protein family, member B4 (NPIPB4), monoamine oxidase B (MAOB), sialic acid acetyltransferase (SIAE), and collagen, type III, alpha 1 (COL3A1)) were significantly lower in saliva of OSCC patients. Receiver operating characteristics (ROC) analysis was used to individually evaluate the predictive power of the potential biomarkers for OSCC diagnosis. The area under the curve (AUC) values were evaluated for the OSCC vs. non-tumor groups via univariate ROC analyses, as well as multivariate ROC analyses of combinations of multiple potential biomarkers. The combination of CYP27A1 + SIAE showed a favorable AUC value of 0.84. When we divided saliva samples into two groups according to age using a 60-year cut-off, with OSCC patients and controls evaluated together, the AUC of MAOB-NAB2 was more predictive of OSCC in the under-60 group (AUC, 0.91; sensitivity, 0.92; and specificity, 0.86) than any other gene combination. These results are expected to aid the early diagnosis of OSCC, especially in patients under 60 years of age. While more studies with larger numbers of patients are necessary, our result suggest that salivary mRNA would be a potent biomarker for early OSCC diagnosis.