Expression of caveolin-1 in tongue squamous cell carcinoma by quantum dots

Increased Plasmatic Levels of Exosomes Are Significantly Related to Relapse Rate in Patients with Oral Squamous Cell Carcinoma: A Cohort Study

BACKGROUND

Oral squamous cell carcinoma (OSCC) is characterized by an immunosuppressive tumor microenvironment. Their plasma-derived exosomes deliver immunomodulatory molecules and cargo that correlate significantly with clinical parameters. This study aims to assess the exosomal profile as a potential tool for early detection of relapse and long-term outcomes in OSCC patients undergoing conventional therapy.

METHODS

27 OSCC patients with a median 38-month follow-up were included in this study. The relationship between NTA-derived parameters and clinical pathological parameters was examined, and receiver operating characteristic (ROC) curves were utilized to evaluate the diagnostic efficacy of these values in detecting cancer relapse.

RESULTS

Plasmatic levels of exosomes prior to surgery showed a drastic reduction after surgical intervention (8.08E vs. 1.41 × 109 particles/mL, p = 0.006). Postsurgical concentrations of exosomes were higher in patients who experienced relapse compared to those who remained disease-free (2.97 × 109 vs. 1.11 × 109 particles/mL, p = 0.046). Additionally, patients who relapsed exhibited larger exosome sizes after surgery (141.47 vs. 132.31 nm, p = 0.03). Patients with lower concentrations of exosomes prior to surgery demonstrated better disease-free survival compared to those with higher levels (p = 0.012). ROC analysis revealed an area under the curve of 0.82 for presurgical exosome concentration in identifying relapse.

CONCLUSIONS

Presurgical exosomal plasmatic levels serve as independent predictors of early recurrence and survival in OSCC. All in all, our findings indicate that the detection of peripheral exosomes represents a novel tool for the clinical management of OSCC, with potential implications for prognosis assessment.

Cholesterol Is a Regulator of CAV1 Localization and Cell Migration in Oral Squamous Cell Carcinoma

Cholesterol plays an important role in cancer progression, as it is utilized in membrane biogenesis and cell signaling. Cholesterol-lowering drugs have exhibited tumor-suppressive effects in oral squamous cell carcinoma (OSCC), suggesting that cholesterol is also essential in OSCC pathogenesis. However, the direct effects of cholesterol on OSCC cells remain unclear. Here, we investigated the role of cholesterol in OSCC with respect to caveolin-1 (CAV1), a cholesterol-binding protein involved in intracellular cholesterol transport. Cholesterol levels in OSCC cell lines were depleted using methyl-β-cyclodextrin and increased using the methyl-β-cyclodextrin-cholesterol complex. Functional analysis was performed using timelapse imaging, and CAV1 expression in cholesterol-manipulated cells was investigated using immunofluorescence and immunoblotting assays. CAV1 immunohistochemistry was performed on surgical OSCC samples. We observed that cholesterol addition induced polarized cell morphology, along with CAV1 localization at the trailing edge, and promoted cell migration. Moreover, CAV1 was upregulated in the lipid rafts and formed aggregates in the plasma membrane in cholesterol-added cells. High membranous CAV1 expression in tissue specimens was associated with OSCC recurrence. Therefore, cholesterol promotes the migration of OSCC cells by regulating cell polarity and CAV1 localization to the lipid raft. Furthermore, membranous CAV1 expression is a potential prognostic marker for OSCC patients.

Cholesterol depletion affects caveolin-1 expression, migration and invasion of oral tongue squamous cell carcinoma cell lines

INTRODUCTION

Cholesterol is a key lipid molecule within cell membranes. This is especially true in cavelolas, invaginated membrane nanodomains, which present the protein caveolin-1 (CAV-1). It is important to note that this structure is involved in many cell signalling pathways. Additionally, high cholesterol is seen in different tumor types but little is known in regards to oral tongue squamous cell carcinoma (OTSCC). The aim of this study was to evaluate the influence of cholesterol depletion on primary (SCC-25) and metastatic (HSC-3) OTSCC cell lines.

MATERIALS AND METHODS

Cell membrane fluidity, cell viability, gene and protein expression of CAV-1 and of epithelial-mesenchymal transition (EMT) markers, cell migration in Myogel and invasion-myoma assay were evaluated after cholesterol depletion with methyl-β-cyclodextrin (MβCD - 7.5, 10 or 15 mM) RESULTS: Decreased cell viability and increased membrane fluidity of SCC-25 cells was seen with cholesterol depletion but cell viability was less affected and there was no effect on membrane fluidity in HSC-3. Cholesterol depletion also decreased CAV-1 at 6 h but increased it after 24 h.; both epithelial and mesenchymal EMT genes were upregulated after 6 h, followed by downregulation at 24 h in SCC-25. In HSC-3, CAV-1 was downregulated, and E-cadherin gene (ECAD) was upregulated at 6 h. Only the protein β-catenin in SCC-25 was affected, and cell migration of both cell lines was decreased, affecting SCC-25 more intensely. The invasive capacity within human myoma organotypic model was increased in SCC-25 and decreased in HSC-3.

CONCLUSION

Cholesterol depletion affects CAV-1 and ECAD inversely. This affect also depends on cell type since the invasive capacity was augmented in primary cells while decreased in metastatic cells.

Identification of Potential Biomarkers Using Integrative Approach: A Case Study of ESCC

This paper presents a consensus-based approach that incorporates three microarray and three RNA-Seq methods for unbiased and integrative identification of differentially expressed genes (DEGs) as potential biomarkers for critical disease(s). The proposed method performs satisfactorily on two microarray datasets (GSE20347 and GSE23400) and one RNA-Seq dataset (GSE130078) for esophageal squamous cell carcinoma (ESCC). Based on the input dataset, our framework employs specific DE methods to detect DEGs independently. A consensus based function that first considers DEGs common to all three methods for further downstream analysis has been introduced. The consensus function employs other parameters to overcome information loss. Differential co-expression (DCE) and preservation analysis of DEGs facilitates the study of behavioral changes in interactions among DEGs under normal and diseased circumstances. Considering hub genes in biologically relevant modules and most GO and pathway enriched DEGs as candidates for potential biomarkers of ESCC, we perform further validation through biological analysis as well as literature evidence. We have identified 25 DEGs that have strong biological relevance to their respective datasets and have previous literature establishing them as potential biomarkers for ESCC. We have further identified 8 additional DEGs as probable potential biomarkers for ESCC, but recommend further in-depth analysis.

Involvement of caveolin-1 in skin diseases

The skin is the outermost layer and largest organ in the human body. Since the skin interfaces with the environment, it has a variety of roles, including providing a protective barrier against external factors, regulating body temperature, and retaining water in the body. It is also involved in the immune system, interacting with immune cells residing in the dermis. Caveolin-1 (CAV-1) is essential for caveolae formation and has multiple functions including endocytosis, lipid homeostasis, and signal transduction. CAV-1 is known to interact with a variety of signaling molecules and receptors and may influence cell proliferation and migration. Several skin-related disorders, especially those of the inflammatory or hyperproliferative type such as skin cancers, psoriasis, fibrosis, and wound healing, are reported to be associated with aberrant CAV-1 expression. In this review, we have explored CAV-1 involvement in skin physiology and skin diseases.

Airway basal cells show regionally distinct potential to undergo metaplastic differentiation

Basal cells are multipotent stem cells of a variety of organs, including the respiratory tract, where they are major components of the airway epithelium. However, it remains unclear how diverse basal cells are and how distinct subpopulations respond to airway challenges. Using single cell RNA-sequencing and functional approaches, we report a significant and previously underappreciated degree of heterogeneity in the basal cell pool, leading to identification of six subpopulations in the adult murine trachea. Among these, we found two major subpopulations, collectively comprising the most uncommitted of all the pools, but with distinct gene expression signatures. Notably, these occupy distinct ventral and dorsal tracheal niches and differ in their ability to self-renew and initiate a program of differentiation in response to environmental perturbations in primary cultures and in mouse injury models in vivo. We found that such heterogeneity is acquired prenatally, when the basal cell pool and local niches are still being established, and depends on the integrity of these niches, as supported by the altered basal cell phenotype of tracheal cartilage-deficient mouse mutants. Finally, we show that features that distinguish these progenitor subpopulations in murine airways are conserved in humans. Together, the data provide novel insights into the origin and impact of basal cell heterogeneity on the establishment of regionally distinct responses of the airway epithelium during injury-repair and in disease conditions.

Quantitative proteomics identifies biomarkers to distinguish pulmonary from head and neck squamous cell carcinomas by immunohistochemistry

The differentiation between a pulmonary metastasis and a newly developed squamous cell carcinoma of the lung in patients with prior head and neck squamous cell carcinoma (HNSCC) is difficult due to a lack of biomarkers but is crucially important for the prognosis and therapy of the affected patient. By using high‐resolution mass spectrometry in combination with stable isotope labelling by amino acids in cell culture, we identified 379 proteins that are differentially expressed in squamous cell carcinomas of the lung and the head and neck. Of those, CAV1, CAV2, LGALS1, LGALS7, CK19, and UGDH were tested by immunohistochemistry on 194 tissue samples (98 lung and 96 HNSCCs). The combination of CAV1 and LGALS7 was able to distinguish the origin of the squamous cell carcinoma with high accuracy (area under the curve 0.876). This biomarker panel was tested on a cohort of 12 clinically classified lung tumours of unknown origin after HNSCC. Nine of those tumours were immunohistochemically classifiable.

Nanoparticles for Oral Cancer Diagnosis and Therapy

Oral cancer is the sixth most common malignant cancer, affecting the health of people with an unacceptably high mortality rate. Despite numerous clinical methods in the diagnosis and therapy of oral cancer (e.g., magnetic resonance imaging, computed tomography, surgery, and chemoradiotherapy), they still remain far from optimal. Therefore, an urgent need exists for effective and practical techniques of early diagnosis and effective therapy of oral cancer. Currently, various types of nanoparticles have aroused wide public concern, representing a promising tool for diagnostic probes and therapeutic devices. Their inherent physicochemical features, including ultrasmall size, high reactivity, and tunable surface modification, enable them to overcome some of the limitations and achieve the expected diagnostic and therapeutic effect. In this review, we introduce different types of nanoparticles that emerged for the diagnosis and therapy of oral cancers. Then, the challenges and future perspectives for nanoparticles applied in oral cancer diagnosis and therapy are presented. The objective of this review is to help researchers better understand the effect of nanoparticles on oral cancer diagnosis and therapy and may accelerate breakthroughs in this field.

Differences in the expression of caveolin-1 isoforms in cancer-associated and normal fibroblasts of patients with oral squamous cell carcinoma

OBJECTIVES

For many years, tumor development has been viewed as a cell-autonomous process; however, today we know that the tumor microenvironment (TME) and especially cancer-associated fibroblasts (CAFs) significantly contribute to tumor progression. Caveolin-1 (Cav-1) is a scaffolding protein which is involved in several cancer-associated processes as important component of the caveolae. Our goal was to shed light on the expression of the two different isoforms of Cav-1 in normal fibroblasts (NFs) and CAFs of patients with oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

Fibroblasts from normal mucosa and CAFs were isolated and propagated in vitro. Gene expression of the different Cav-1 isoforms was assessed via quantitative real-time PCR (qPCR) and supplemented by protein expression analysis.

RESULTS

We could show that the Cav-1β isoform is more highly expressed in NFs and CAFs compared to Cav-1α. Furthermore, the different Cav-1 isoforms tended to be differently expressed in different tumor stages. However, this trend could not be seen consistently, which is in line with the ambiguous role of Cav-1 in tumor progression described in literature. Western blotting furthermore revealed that NFs and CAFs might differ in the oligomerization profile of the Cav-1 protein.

CONCLUSION

These differences in expression of Cav-1 between NFs and CAFs of patients with OSCC confirm that the protein might play a role in tumor progression and is of interest for further analyses.

CLINICAL RELEVANCE

Our findings support a possible role of the two isoforms of Cav-1 in the malignant transformation of OSCC.

Identification of four key prognostic genes and three potential drugs in human papillomavirus negative head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is a common tumor worldwide with poor prognosis. The pathogenesis of human papillomavirus (HPV)-positive and HPV-negative HNSCCs differs. However, few studies have considered the HPV status when identifying biomarkers for HNSCC. Thus, the identification of biomarkers for HPV-positive and HPV-negative HNSCCs is urgently needed.

METHODS

Three microarray datasets from Gene Expression Omnibus (GEO) were analyzed, and the differentially expressed genes (DEGs) were obtained. Then, functional enrichment pathway analysis was performed and protein-protein interaction (PPI) networks were constructed. The expression of hub genes at both the mRNA and protein level was determined in Oncomine, The Cancer Genome Atlas (TCGA) and the Human Protein Atlas (HPA). In addition, survival analysis of the patient stratified by HPV status and the expression levels of key genes were performed based on TCGA data. The role of AREG, STAG3, CAV1 and C19orf57 in cancer were analyzed through Gene set enrichment analysis (GSEA). The top ten small molecule drugs were identified and the therapeutic value of zonisamide, NVP-AUY922, PP-2 and fostamatinib was further evaluated in six HPV-negative HNSCC cell lines. Finally, the therapeutic value of NVP-AUY922 was tested in vivo based on three HPV-negative HNSCC models, and statistical analysis was performed.

RESULTS

In total, 47 DEGs were obtained, 11 of which were identified as hub genes. Biological process analysis indicated that the hub genes were associated with the G1/S transition of the mitotic cell cycle. Survival analysis uncovered that the prognostic value of AREG, STAG3, C19orf57 and CAV1 differed between HPV-positive and HPV-negative patients. Gene set enrichment analysis (GSEA) showed the role of AREG, STAG3 and CAV1 in dysregulated pathways of tumor. Ten small molecules were identified as potential drugs specifically for HPV-positive or HPV-negative patients; three-NVP-AUY922, fostamatinib and PP-2-greatly inhibited the proliferation of six HPV-negative HNSCC cell lines in vitro, and NVP-AUY922 inhibited three HPV-negative HNSCC xenografts in vivo.

CONCLUSIONS

In conclusion, AREG, STAG3, C19orf57 and CAV1 are key prognostic factors and potential therapeutic targets in HPV-negative HNSCC. NVP-AUY922, fostamatinib and PP-2 may be effective drugs for HPV-negative HNSCC.

Exosomes in head and neck cancer. Updating and revisiting

Exosomes have gone from being considered simple containers of intracellular waste substances to be considered important carriers of cellular signals. Its broad capacity to promote tumour growth, both in situ and metastatic, has greatly intensified scientific research on them. In the same way and depending on its content, its tumour suppressive properties have opened a window of light and hope in the fight against cancer. In the present review we try to gather in a simple and understandable way the most relevant knowledge to date on the role of exosomes in oral squamous cell carcinoma, helping to understand their process of formation, release and activity on the tumour microenvironment.

A Pilot Clinical Study on the Prognostic Relevance of Plasmatic Exosomes Levels in Oral Squamous Cell Carcinoma Patients

Background: To evaluate the relationship between the plasmatic CD63 and CAV1 positive exosome levels, in patients with OSCC before and after surgical treatment and to correlate it with their overall survival. Methods: A double-blind pilot study over 10 patients OSCC and T4 stage without distant metastases or local bone invasion has been performed. The average follow-up period was 37.64 months (34.3–40.84). We obtained 2 plasma tubes of 1 mL each before surgery and 7 days after surgery. Before performing the immunocapture-based analysis, EVs (Extracellular Vesicles) were isolated from the plasma and characterized with western blot analysis. Results: Mean values of CD63 positive plasmatic exosomes (EXO-CD63) after surgery decreased from 750.88 ± 286.67 to 541.71 ± 244.93 (p = 0.091). On the other hand, CAV-1 positive plasmatic exosomes (EXO-CAV-1) increased after surgery from 507 ± 483.39 to 1120.25 ± 1151.17 (p = 0.237). Patients with EXO-CD63 levels lower than the mean global value before the surgery had a survival of 36.04 months compared with the group with EXO-CD63 higher than the average who only survived 12.49 ± 1.67 months from the diagnosis, p = 0.225. When EXO-CAV-1 levels before surgery was lower than the average (813.94 ± 801.21) overall survival was 24.69 ± 22.23 months in contrast when it was higher that was only 11.64 months, p = 0.157. Patients with lower EXO-CD63 levels after surgery lived an average of 23.84 ± 23.9 months, while those with higher plasmatic levels of EXO-CD63 live 13.35 months, p = 0.808. When EXO-CAV-1 levels after surgery were lower, the average overall survival was 20.344 ± 15.40 months, in contrast when the EXO-CAV-1 levels were higher showing rather an estimate survival expectation of 1.64 months. Conclusions: Surgical treatment induced a dramatic reduction of the plasmatic levels of exosomes expressing CD63 as early as 1 week after resection. This first result suggests that the tumour mass is responsible of the high levels of circulating exosomes detected in cancer patients. At the same time point exosome expressing CAV-1 increased, possibly due to the inflammatory reaction immediately after surgery. Lastly, statistical analysis showed that lower levels of plasmatic exosomes both before and after surgery correlated with a better life expectancy of OSCC patients. Hopefully, this approach will prove useful in the clinical follow-up of cancer patients.

Caveolin-1, cancer and therapy resistance

Resistance of solid tumors to chemo- and radiotherapy remains a major obstacle in anti-cancer treatment. Herein, the membrane protein caveolin-1 (CAV1) came into focus as it is highly expressed in many tumors and high CAV1 levels were correlated with tumor progression, invasion and metastasis, and thus a worse clinical outcome. Increasing evidence further indicates that the heterogeneous tumor microenvironment, also known as the tumor stroma, contributes to therapy resistance resulting in poor clinical outcome. Again, CAV1 seems to play an important role in modulating tumor host interactions by promoting tumor growth, metastasis, therapy resistance and cell survival. However, the mechanisms driving stroma-mediated tumor growth and radiation resistance remain to be clarified. Understanding these interactions and thus, targeting CAV1 may offer a novel strategy for preventing cancer therapy resistance and improving clinical outcomes. In this review, we will summarize the resistance-promoting effects of CAV1 in tumors, and emphasize its role in the tumor-stroma communication as well as the resulting malignant phenotype of epithelial tumors.

Caveolin-1 expression in oral lichen planus, dysplastic lesions and squamous cell carcinoma

Caveolin-1(Cav-1), the main part of caveolae structure, is supposed to play a role in pathogenesis of many human tumors. Since oral lichen planus (OLP) is considered as a potential premalignant disease, this study evaluated Cav-1 expression in OLP in comparison with benign hyperkeratosis, dysplastic epithelium and oral squamous cell carcinoma (OSCC), to investigate its possible role in pathogenesis and malignant transformation of OLP. In this cross-sectional retrospective study, immunohistochemical expression of Cav-1 in the epithelial component and stroma was evaluated in 81 samples, including 12 cases of hyperkeratosis, 24 OLP, 22 epithelial dysplasia, and 23 OSCC samples. Correlations between Cav-1 expression and clinicopathological variables were evaluated statistically. Positive Cav-1 staining was found in 58% of OLP, 91% of hyperkeratosis, 100% of epithelial dysplasia, and 95% of OSCC samples. OSCC showed the highest Cav-1 expression and OLP had the lowest (P=0.001). The intensity of staining was significantly increased in stepwise manner from OLP to OSCC (P=0.001). Expression of Cav-1 was related to the grade of samples in OSCC and dysplastic samples (P=0.04). Based on the findings, it was concluded that Cav-1 may play a role in the pathogenesis of OLP and carcinogenesis of SCC, but its role in malignant transformation of OLP is not confirmed. Further studies are needed to evaluate its potential therapeutic function in OLP and SCC.

The different functions and clinical significances of caveolin-1 in human adenocarcinoma and squamous cell carcinoma

Caveolin-1 (Cav-1), a major structural protein of caveolae, is an integral membrane protein which plays an important role in the progression of carcinoma. However, whether Cav-1 acts as a tumor promoter or a tumor suppressor still remains controversial. For example, the tumor-promoting function of Cav-1 has been found in renal cancer, prostate cancer, tongue squamous cell carcinoma (SCC), lung SCC and bladder SCC. In contrast, Cav-1 also plays an inhibitory role in esophagus adenocarcinoma, lung adenocarcinoma and cutaneous SCC. The role of Cav-1 is still controversial in thyroid cancer, hepatocellular carcinoma, gastric adenocarcinoma, colon adenocarcinoma, breast cancer, pancreas cancer, oral SCC, laryngeal SCC, head and neck SCC, esophageal SCC and cervical SCC. Besides, it has been reported that the loss of stromal Cav-1 might predict poor prognosis in breast cancer, gastric cancer, pancreas cancer, prostate cancer, oral SCC and esophageal SCC. However, the accumulation of stromal Cav-1 has been found to be promoted by the progression of tongue SCC. Taken together, Cav-1 seems playing a different role in different cancer subtypes even of the same organ, as well as acting differently in the same cancer subtype of different organs. Thus, we hereby explore the functions of Cav-1 in human adenocarcinoma and SCC from the perspective of clinical significances and pathogenesis. We envision that novel targets may come with the further investigation of Cav-1 in carcinogenesis.

The prognostic role of E-cadherin and β-catenin overexpression in laryngeal squamous cell carcinoma

OBJECTIVES/HYPOTHESIS

Epithelial-to-mesenchymal transition (EMT) consists of a rapid and reversible change in the cellular phenotype toward the mesenchymal cell phenotype that facilitates cell migration and invasion of the tumor into surrounding tissues followed by metastasis. In the present study, we sought to determine the clinical significance of E-cadherin, N-cadherin, β-catenin, α-catenin, γ-catenin, caveolin-1, and vimentin in a cohort of patients with stage I to IVA laryngeal squamous cell carcinoma (LSCC) treated with surgery with or without adjuvant therapy using immunohistochemical analyses.

STUDY DESIGN

Individual retrospective cohort study.

METHODS

E-cadherin, N-cadherin, β-catenin, α-catenin, γ-catenin, caveolin-1, and vimentin immunohistochemical expression were evaluated in a cohort of 82 patients with stages I to IVA LSCC. The Fisher exact test was used for categorical variables, and the Mann-Whitney test where appropriate for continuous variables. Survival comparisons was performed using the log-rank test. A multivariate analysis using the Cox proportional hazards model was performed and considered all EMT markers.

RESULTS

In multivariate analysis, T stage was an independent risk factor for adverse disease-specific survival (DSS) and overall survival (OS) (P = .025 and .019, respectively). Cytoplasmic β-catenin overexpression was independently associated with a longer DSS (P = .0007), and E-cadherin overexpression was found to be an independent risk factor for poor OS (P = .030).

CONCLUSIONS

E-cadherin and β-catenin pathways could represent future therapeutic targets in the treatment of LSCC. However, validation of our results in prospective cohorts of patients with LSCCs is required before their clinical implementation.

LEVEL OF EVIDENCE

NA.

Analyzing simultaneous positive expression of EZH2 and P53 protein to improve predictive value in cervical squamous cell carcinoma

OBJECTIVE

The current study was undertaken to investigate the predictive value of simultaneous enhancer of zeste homolog 2 (EZH2) and P53 expression in lesions of patients with cervical squamous cell carcinoma.

METHODS

Quantum dot double fluorescence staining was applied to detect EZH2 and P53 protein in biopsy tissue of 168 patients with cervical squamous cell carcinoma. The expression was classified into double positive (EZH2 and P53 were positively expressed), single positive (either EZH2 or P53 was positively expressed), and double negative (neither was positively expressed). The EZH2 and P53 expression, clinical stages of cervical cancer, lymph node metastasis, progression-free survival, and overall survival were analyzed.

RESULTS

A relationship of EZH2 and P53 expression with the clinical stage of cervical cancer and lymph node metastasis was indicated. Simultaneous detection of both proteins could partly predict prognosis, consistent with previous studies' results. The current study demonstrated that the expression levels of EZH2 and P53 in tumor tissue and the proportion of cases with double-positive expression significantly increased with increasing clinical stages of cancer, also confirming up-regulated expression of EZH2 and P53 with increasing stages. These findings may suggest that the 2 proteins were involved in the development of cervical cancer, but the nature of their interaction is undefined. The increase of EZH2 and P53 expression in patients with lymph node metastasis indicated that they may be involved in metastasis of cervical cancer.

CONCLUSION

Simultaneous positive EZH2 and P53 expression could improve the predictive value of a poor prognosis in cervical cancer.

Caveolin 1 (Cav-1) and actin-related protein 2/3 complex, subunit 1B (ARPC1B) expressions as prognostic indicators for oral squamous cell carcinoma (OSCC)

Caveolin-1 (Cav-1) and Actin-Related Protein 2/3 Complex, Subunit 1B (ARPC1B) have been implicated in various human cancers, yet its role in tumorigenesis remains controversial. Therefore, this study aims to determine the protein expression of these two genes in oral squamous cell carcinomas (OSCCs) and to evaluate the clinical and prognostic impact of these genes in OSCC. Protein expressions of these two genes were determined by immunohistochemistry technique. The association between Cav-1 and ARPC1B with clinico-pathological parameters was evaluated by Chi-square test (or Fisher exact test where appropriate). Correlation between the protein expressions of these 2 genes with survival was analyzed using Kaplan-Meier and Cox regression models. Cav-1 and ARPC1B were found to be significantly over-expressed in OSCC compared to normal oral mucosa (p = 0.002 and p = 0.033, respectively). Low level of ARPC1B protein expression showed a significant correlation with lymph node metastasis (LNM) (p = 0.010) and advanced tumor staging (p = 0.003). Kaplan-Meier survival analyses demonstrated that patients with over-expression of Cav-1 protein were associated with poor prognosis (p = 0.030). Adjusted multivariate Cox regression model revealed that over-expression of Cav-1 remained as an independent significant prognostic factor for OSCC (HRR = 2.700, 95 % CI 1.013-7.198, p = 0.047). This study demonstrated that low-expression of ARPC1B is significantly associated with LNM and advanced tumor staging whereas high expression of Cav-1 can be a prognostic indicator for poor prognosis in OSCC patients.

Caveolin-1 accumulation in the tongue cancer tumor microenvironment is significantly associated with poor prognosis: an in-vivo and in-vitro study

Background

Caveolin-1 (CAV1) may be upregulated by hypoxia and acts in a tumor-dependent manner. We investigated CAV1 in tongue squamous cell carcinoma (TSCC) and its association with clinical outcomes, and studied in vitro possible ways for CAV1 accumulation in the tumor microenvironment (TME).

Methods

TSCC cases (N = 64) were immunohistochemically stained for CAV1. Scores were separately assessed in the tumor and TME and plotted for association with recurrence and survival (univariate analysis with log-rank test). In vitro studies were performed on a 3D myoma organotypic model, a mimicker of TME. Prior to monoculturing HSC-3 tongue cancer cells, the model underwent modifications in oxygenation level (1%O₂ hypoxia to upregulate CAV1) and/or in the amount of natural soluble factors [deleted by 14-day rinsing (rinsed myoma, RM), to allow only HSC-3-derived factors to act]. Controls included normoxia (21%O₂) and naturally occurring soluble factors (intact myoma, IM). HSC-3 cells were also co-cultured with CaDEC12 cells (fibroblasts exposed to human tongue cancer). CAV1 expression and cellular distribution were examined in different cellular components in hypoxic and rinsed myoma assays. Twist served as a marker for the process of epithelial-mesenchymal transition (EMT). Exosomes isolated from HSC-3 media were investigated for containing CAV1.

Results

Expression of CAV1 in TSCC had a higher score in TME than in the tumor cells and a negative impact on recurrence (p = 0.01) and survival (p = 0.003). Monocultures of HSC-3 revealed expression of CAV1 mainly in the TME-like myoma assay, similar to TSCC. CAV1+, alpha-smooth muscle actin (αSMA) + and Twist + CAF-like cells were observed surrounding the invading HSC-3, possibly reflecting EMT. RM findings were similar to IM, inferring action of HSC-3 derived factors, and no differences were seen when hypoxia was induced. HSC-3-CaDEC12 co-cultures revealed CAV1+, αSMA+ and cytokeratin-negative CAF-like cells, raising the possibility of CaDEC12 cells gaining a CAF phenotype. HSC-3-derived exosomes were loaded with CAV1.

Conclusions

Accumulation of CAV1-TME in TSCC had a negative prognostic value. In vitro studies showed the presence of CAV1 in cancer cells undergoing EMT and in fibroblasts undergoing trans-differentiation to CAFs. CAV1 delivery to the TME involved cancer cell-derived exosomes.

Caveolin and cavin family members: dual roles in cancer

Caveolae are specialized plasma membrane subdomains with distinct lipid and protein compositions, which play an essential role in cell physiology through regulation of trafficking and signaling functions. The structure and functions of caveolae have been shown to require the proteins caveolins. Recently, members of the cavin protein family were found to be required, in concert with caveolins, for the formation and function of caveolae. Caveolins have a paradoxical role in the development of cancer formation. They have been involved in both tumor suppression and oncogenesis, depending on tumor type and progress stage. High expression of caveolins and cavins leads to inhibition of cancer-related pathways, such as growth factor signaling pathways. However, certain cancer cells that express caveolins and cavins have been shown to be more aggressive and metastatic because of their increased potential for anchorage-independent growth. Here, we will survey the functional roles of caveolins and of different cavin family members in cancer regulation.

Caveolin-1 in oral squamous cell carcinoma microenvironment: an overview

Caveolin-1 plays an important role in the pathogenesis of oncogenic cell transformation, tumorigenesis, and metastasis. Increased expression of caveolin-1 in an array of tumors has confirmed its value in prognosis. It has been established that oxidative stress is the main cause for loss of stromal caveolin-1 via autophagy in the tumor microenvironment. In this overview, we attempt to abridge the relationship between caveolin-1 and oral squamous cell carcinoma, taking all the established theories into consideration.

Prognostic and predictive values of SPP1, PAI and caveolin-1 in patients with oral squamous cell carcinoma

SPP1, PAI and caveolin-1 are known to be closely associated with tumor progression in several kinds of human tumors. This study aimed to investigate the expression of SPP1, PAI and caveolin-1 in oral squamous cell carcinoma (OSCC), and to evaluate their association with the prognosis in oral carcinoma. Immunohistochemical staining was used to examine the expression of SPP1, PAI and caveolin-1 in 17 normal oral mucosa, 6 oral epithelial dysplasia and 43 OSCC specimens by tissue microarrays. High expression of SPP1, PAI and caveolin-1 was found in OSCC patients, and SPP1 and PAI expression were significantly higher in OSCC than in normal oral mucosa. No significant correlations were found between SPP1, PAI and caveolin-1 expression and clinicopathological factors. Expression of SPP1, PAI and caveolin-1 was also not associated with overall survival. Moreover, SPP1 was closely correlated with PAI, caveolin-1 and Keap1, and PAI had significant correlations with caveolin-1, Keap1 and Nrf2, and caveolin-1 was associated with Keap1 by using the Pearson correlation coefficient test. Our findings suggest that overexpressed SPP1, PAI and caveolin-1 were linked to carcinogenesis and progression, and thus they may serve as potential prognostic factors in OSCC.

A novel orthotopic mouse model of head and neck cancer and lymph node metastasis

Prognosis of head and neck squamous cell carcinoma (HNSCC) is largely determined by the extent of lymph node (LN) metastasis at diagnosis, and this appears to be controlled by cancer cell genetics. To examine the role of these genes in LN metastasis, we created a human-in-mouse orthotopic model of HNSCC and performed comparative microarray analysis of gene expression between populations of HNSCC cell lines derived before and after serial transplantation and in vivo metastasis in mice. Microarray analysis comparing the USC-HN3-GFP, USC-HN3-GFP-G1 and USC-HN3-GFP-G2 cell lines identified overexpression of genes implicated in epithelial-to- mesenchymal transition and the formation of cancer stem cells, including CAV-1, TLR-4 (Toll-like receptor 4), MMP-7 (matrix metalloproteinase 7), ALDH1A3, OCT-4 and TRIM-29. Ingenuity Pathway Analysis confirmed upregulation of respective gene signaling pathways in the USC-HN1-GFP-G2 cell line. Patient HNSCC samples from advanced stages overexpressed ALDH1A3, CAV-1 and MMP-7. Our results show that CAV-1, TLR-4, MMP-7, ALDH1A3, OCT-4 and TRIM-29 have increased expression in HNSCC cells selected for an enhanced metastatic phenotype and suggest that these genes may have an important role in the metastatic potential of HNSCC cells. Inhibition of these genes may therefore have prognostic and therapeutic utility in HNSCC.

Caveolin-1 expression level in cancer associated fibroblasts predicts outcome in gastric cancer

Aims

Altered expression of epithelial or stromal caveolin-1 (Cav-1) is observed in various types of human cancers. However, the clinical significance of Cav-1 expression in gastric cancer (GC) remains largely unknown. The present study aims to explore the clinicopathological significance and prognostic value of both tumor cells and cancer associated fibroblasts (CAFs) Cav-1 in GC.

Methods and Results

Quantum dots immunofluorescence histochemistry was performed to examine the expression of Cav-1 in 20 cases of gastritis without intestinal metaplasia (IM), 20 cases of gastritis with IM and 286 cases of GC. Positive rates of epithelial Cav-1 in gastritis without IM, gastritis with IM and GC showed a decreasing trend (P = 0.012). Low expression of Cav-1 in CAFs but not in tumor cells was an independent predictor of poor prognosis in GC patients (P = 0.034 and 0.005 respectively in disease free survival and overall survival). Cav-1 level in tumor cells and CAFs showed no significant correlation with classic clinicopathological features.

Conclusions

Loss of epithelial Cav-1 may promote malignant progression and low CAFs Cav-1 level herald worse outcome of GC patient, suggesting CAFs Cav-1 may be a candidate therapeutic target and a useful prognostic marker of GC.

On the future contents of a small journal of histochemistry

In the last three years, more than 70,000 scientific articles have been published in peer reviewed journals on the application of histochemistry in the biomedical field: most of them did not appear in strictly histochemical journals, but in others dealing with cell and molecular biology, medicine or biotechnology. This proves that histochemistry is still an active and innovative discipline with relevance in basic and applied biological research, but also demonstrates that especially the small histochemical journals should likely reconsider their scopes and strategies to preserve their authorship. A review of the last three years volumes of the European Journal of Histochemistry, taken as an example of a long-time established small journal, confirmed that the published articles were widely heterogeneous in their topics and experimental models, as in this journal's tradition. This strongly suggests that a journal of histochemistry should keep its role as a forum open to an audience as broad as possible, publishing papers on cell and tissue biology in a wide variety of models. This will improve knowledge of the basic mechanisms of development and differentiation, while helping to increase the number of potential authors since scientists who generally do not use histochemistry in their research will find hints for the applications of histochemical techniques to novel still unexplored subjects.

Identifying pathological biomarkers: histochemistry still ranks high in the omics era

In recent years, omic analyses have been proposed as possible approaches to diagnosis, in particular for tumours, as they should be able to provide quantitative tools to detect and measure abnormalities in gene and protein expression, through the evaluation of transcription and translation products in the abnormal vs normal tissues. Unfortunately, this approach proved to be much less powerful than expected, due to both intrinsic technical limits and the nature itself of the pathological tissues to be investigated, the heterogeneity deriving from polyclonality and tissue phenotype variability between patients being a major limiting factor in the search for unique omic biomarkers. Especially in the last few years, the application of refined techniques for investigating gene expression in situ has greatly increased the diagnostic/prognostic potential of histochemistry, while the progress in light microscopy technology and in the methods for imaging molecules in vivo have provided valuable tools for elucidating the molecular events and the basic mechanisms leading to a pathological condition. Histochemical techniques thus remain irreplaceable in pathologist's armamentarium, and it may be expected that even in the future histochemistry will keep a leading position among the methodological approaches for clinical pathology.

Histochemistry through the years, browsing a long-established journal: novelties in traditional subjects

Histochemical journals represent a traditional forum where methodological and technological improvements can be presented and validated in view of their applications to investigate not only cytology and histology in normal and diseased conditions but to test as well hypotheses on more basic issues for life sciences, such as comparative and evolutionary biology. The earliest scientific journals on histochemistry began their publication in the first half of the ‘50s of the last century, and their readership did not probably change over the years; rather, the authors’ interests may have progressively been changing as well as the main topics of their articles. This hypothesis is discussed, based on the subjects of the article published in the first and last ten years in the European Journal of Histochemistry, as an example of old journal which started publication in 1954, being since then the official organ of the Italian Society of Histochemistry. This survey confirmed that histochemistry has provided and still offers unique opportunities for studying the structure, chemical composition and function of cells and tissues in a wide variety of living organisms, especially when the topological distribution of specific molecular components has diagnostic or predictive significance, as it occurs in human and veterinary biology and pathology. Some subjects (e.g. histochemistry applied to muscle cells or to mineralized tissues) have recently become rather popular, whereas a wider application of the histochemical approach may be envisaged for plant cells and tissues.