Mutual paracrine effects of oral squamous cell carcinoma cells and normal oral fibroblasts: induction of fibroblast to myofibroblast transdifferentiation and modulation of tumor cell proliferation

A primary tumor gene expression signature identifies a crucial role played by tumor stroma myofibroblasts in lymph node involvement in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the most common oral and pharyngeal cancer, and is responsible of approximately 3% of cancers in men and 2% in women in the Western World, with increasing incidence rates in developing countries. Early detection by screening is necessary to prevent fatal disease because early, curable lesions are rarely symptomatic. The overall 5-yr survival rate is approximately 50% when surgery, radiation, or both are employed as treatment options, but lymph node involvement greatly influences this estimate, by decreasing the survival rate by about 50%. Here, we aimed at finding genetic signatures associated with lymph node metastasis in OSCC patients. We addressed this issue by whole transcriptome analysis through microarray expression profiling of a set of OSSC specimens of patients without lymph node involvement (10 patients, mean age ± SD 61.2±13.8, male 7, female 3) and with lymph node involvement (11 patients, mean age ± SD 62.1±15.1, male 8, female 3). We evidenced a gene expression signature associated to muscle contraction-related genes in specimens obtained from OSCC patients with lymph node involvement. This gene signature suggests the presence of myofibroblasts in tumor stoma of patients with lymph node involvement and emphasizes the decisive role played by myofibroblasts probably through their secretome in determining OSCC invasiveness.

Precise and Arbitrary Deposition of Biomolecules onto Biomimetic Fibrous Matrices for Spatially Controlled Cell Distribution and Functions

Advances in nano-/microfabrication allow the fabrication of biomimetic substrates for various biomedical applications. In particular, it would be beneficial to control the distribution of cells and relevant biomolecules on an extracellular matrix (ECM)-like substrate with arbitrary micropatterns. In this regard, the possibilities of patterning biomolecules and cells on nanofibrous matrices are explored here by combining inkjet printing and electrospinning. Upon investigation of key parameters for patterning accuracy and reproducibility, three independent studies are performed to demonstrate the potential of this platform for: i) transforming growth factor (TGF)-β1-induced spatial differentiation of fibroblasts, ii) spatiotemporal interactions between breast cancer cells and stromal cells, and iii) cancer-regulated angiogenesis. The results show that TGF-β1 induces local fibroblast-to-myofibroblast differentiation in a dose-dependent fashion, and breast cancer clusters recruit activated stromal cells and guide the sprouting of endothelial cells in a spatially resolved manner. The established platform not only provides strategies to fabricate ECM-like interfaces for medical devices, but also offers the capability of spatially controlling cell organization for fundamental studies, and for high-throughput screening of various biomolecules for stem cell differentiation and cancer therapeutics.

Ki67, CD105, and α-SMA expressions better relate the binary oral epithelial dysplasia grading system of World Health Organization

BACKGROUND

The binary system of oral epithelial dysplasia (OED) has never been investigated with reference to the carcinogenesis-related biomarkers. Hence, Ki67, CD105, and α-SMA immune-expressions were studied in oral potentially malignant disorders (OPMDs) to assess their relationship with the binary OED grading system of World Health Organization.

METHODS

The study was carried out on paraffin-embedded tissues of 30 normal oral mucosa (NOM) and 140 OPMD cases. OPMD cases were classified into two groups "no/questionable/hyperkeratosis/mild"=low-risk epithelial dysplasia (LRED) and "moderate or severe"=high-risk epithelial dysplasia (HRED). The immunohistochemistry was carried out to evaluate the expression of Ki67, CD 105, and α-SMA antigen.

RESULTS

According to the binary grading system of WHO, 69 (49.28%) cases were LRED, while 71 (50.71%) case showed HRED. There was significant increase in Ki67 labeling index (LI) from NOM to LRED to HRED (P=.000). Similarly, mean vascular density (MVD) also increased significantly from NOM to LRED to HRED (P=.000). The α-SMA expression was significantly higher in HERD compared to LRED and NOM (P=.000). A positive correlation was noted among Ki67 LI, MVD, and α-SMA expressions in NOM, LRED, and HRED (P=.000).

CONCLUSION

The expressions of ki67, CD105, and α-SMA markers compliment binary grading system of OED in OPMDS, thus justifying its use in clinical practice.

Tumor Microenvironment on a Chip: The Progress and Future Perspective

Tumors develop in intricate microenvironments required for their sustained growth, invasion, and metastasis. The tumor microenvironment plays a critical role in the malignant or drug resistant nature of tumors, becoming a promising therapeutic target. Microengineered physiological systems capable of mimicking tumor environments are one emerging platform that allows for quantitative and reproducible characterization of tumor responses with pathophysiological relevance. This review highlights the recent advancements of engineered tumor microenvironment systems that enable the unprecedented mechanistic examination of cancer progression and metastasis. We discuss the progress and future perspective of these microengineered biomimetic approaches for anticancer drug prescreening applications.

Cyclosporine A inhibits TGF-β2-induced myofibroblasts of primary cultured human pterygium fibroblasts

Cyclosporine A (CsA), an immunomodulatory drug, and is increasingly used to treat moderate dry eye syndrome and ocular surface inflammation. However, any inhibitory effect on differentiation of fibroblasts to myofibroblasts remains unclear. Here, we show that the inhibitory effect of CsA on transforming growth factor-beta2 (TGF-β2)-induced myofibroblasts in primary cultured human pterygium fibroblasts. CsA significantly decreased mRNA and protein expression of myofibroblast-related markers including α-SMA, laminin, and fibronectin. These findings were supported by the results from immunofluorescence staining. Taken together, these results indicate the therapeutic potential of CsA against pterygium progression. Further studies are necessary to elucidate the precise intracellular signal mechanism responsible for CsA-induced downregulation of myofibroblast markers in pterygium fibroblasts.

Expression of Myofibroblasts in Oral Squamous Cell Carcinoma: An Immunohistochemical Study

INTRODUCTION

Oral squamous cell carcinoma (OSCC) is one of the most common types of malignancy affecting the orafacial region and with a high mortality rate. The fact that stroma of the tumor modulates and facilitates the progression and metastasis of the malignancy has been shown in the past studies. The cells of the activated stroma that are responsible for the progression and metastasis of the tumor are the fibroblasts having smooth muscle properties. These myofibroblasts are said to secrete numerous inflammatory mediators and factors which are said to play a crucial role in tumor progression. Therefore, we evaluated the presence of myofibroblasts in OSCC, by immunohisto-chemistry using alpha smooth muscle actin (a-SMA) antibody.

MATERIALS AND METHODS

We evaluated a total of 50 biopsy specimens from the archives of the oral pathology, where 20 specimens out of 50 were of well-differentiated OSCC (WDOSCC), 20 were of poorly differentiated OSCC (PDOSCC), and 10 were of normal healthy controls. All the specimens were stained by immunohistochemically using with monoclonal antihuman α-SMA. Etemad-Moghadam et al method was used for assessing the myofibroblast distribution. Staining index was evaluated for the groups and compared. All the results were analyzed by Statistical Package for the Social Sciences (SPSS) software.

RESULTS

The mean percentage of myofibroblasts score for WDOSCC and PDOSCC were 2.88 and 2.92 respectively. The mean staining intensity score in WDOSCC and PDOSCC were 2.88 and 2.55 respectively. Statistically significant results were obtained while comparing the final staining index score between the OSCC group and normal control group. No significant correlation could be obtained while comparing the mean staining index score in between WDOSCC and PDOSCC.

CONCLUSION

Malignant epithelium might induce the adjacent stromal tissue to produce myofibroblasts. These specialized cells may be utilized as therapeutic targets for the treatment of OSCC.

CLINICAL SIGNIFICANCE

Proliferation of myofibroblasts may be used as a stromal marker of premalignancy and malignancy.

Evaluation of Role of Myofibroblasts in Oral Cancer: A Systematic Review

Aim

To conduct a systematic review on the role of myofibroblasts in progression of oral cancer. The myofibroblast is essential for the integrity of the mammalian body by virtue of its role in wound healing, but it also plays a negative role due to their role in promoting tumor development.

Settings and design

Systematic review.

Materials and methods

Bibliographic searches were conducted in several electronic databases using all publications in PubMed, PubMed central, EMBASE, CancerLit, Google scholar, and Cochrane CCTR between 1990 and June 2015.

Results

The search of all publications from various electronic databases revealed 1,371 citations. The total number of studies considered for systematic review was 43. The total number of patients included in the studies was 990.

Conclusion

Myofibroblasts are a significant component in stroma of oral cancer cases, though not identified in all cases. This systematic review shows that clinical, pathological, and immunohistochemistry tests have correlated the presence of high myofibroblast count in oral cancer cell stroma.

Key Messages

Myofibroblasts play a significant role in oral cancer invasion and progression. Various studies have demonstrated their association with oral cancer. This review tends to highlight their role in the pathogenesis of oral cancer over the decade.

How to cite this article

Sekhon HK, Sircar K, Kaur G, Marwah M. Evaluation of Role of Myofibroblasts in Oral Cancer: A Systematic Review. Int J Clin Pediatr Dent 2016;9(3):233-239.

Significance of oral cancer-associated fibroblasts in angiogenesis, lymphangiogenesis, and tumor invasion in oral squamous cell carcinoma

BACKGROUND

Cancer-associated fibroblasts (CAFs) are recognized as a pivotal promoter in cancer initiation and development. However, the role of CAFs in the progression and metastasis of oral squamous cell carcinoma (OSCC) has not been fully elucidated.

MATERIALS AND METHODS

Lymphatic vessel density (LVD) and microvessel density (MVD) and the expression of α-smooth muscle actin (α-SMA) and matrix metalloproteinase-9 (MMP-9) were evaluated by immunohistochemistry in 86 cases of OSCC. The correlations between α-SMA expression and MMP-9 expression, LVD, MVD, and other clinicopathological parameters were analyzed. In vitro invasion assay was performed to assess the effect of CAFs on the invasion of OSCC cells. We also investigated the effect of CAFs on the angiogenesis and lymphangiogenesis by inoculating CAFs with OSCC cells into nude mice subcutaneously.

RESULTS

Positive expression of α-SMA protein was detected in 69.8% of the tumors. Increased α-SMA expression was correlated strongly with enhanced tumor invasion, higher tumor grade, increased risk of recurrence, lymph node involvement, and higher peritumoral lymphatic vessel density and microvessel density (P < 0.05). CAFs induced more cancer cells to invade relative to normal fibroblasts (NFs) (P < 0.05). Compared with co-injection of OSCC cells and NFs or injection of tumor cells alone, co-injection of OSCC cells and CAFs resulted in earlier tumor formation and bigger tumor volume accompanied with increased angiogenesis and lymphangiogenesis (P < 0.05).

CONCLUSION

CAFs may play critical roles in OSCC progression as an inducer of tumor invasion, angiogenesis, and lymphangiogenesis. Therapeutic strategies targeting CAFs against OSCC is promising and need further exploration.

NOTCH3 Is Induced in Cancer-Associated Fibroblasts and Promotes Angiogenesis in Oral Squamous Cell Carcinoma

Recent studies have shown that Notch signaling is involved in many types of cancers, including oral squamous cell carcinomas (OSCCs). However, the role of Notch signaling in the tumor microenvironment is not yet fully understood. In this study, we investigated the roles of NOTCH3 signaling in cancer associated fibroblasts (CAFs) in OSCCs. Immunohistochemical study of 93 human tongue OSCC cases indicated that about one third of OSCCs showed NOTCH3 expression in CAFs, and that this expression significantly correlated with tumor-size. In vitro study showed that OSCC cell lines, especially HO1-N-1 cells stimulated NOTCH3 expression in normal human dermal fibroblasts (NHDFs) through direct cell-to-cell contact. Immunohistochemical and morphometric analysis using human OSCC samples demonstrated that NOTCH3 expression in CAFs significantly correlated with micro-vessel density in cancer stroma. In vitro angiogenesis assays involving co-culture of NHDFs with HO1-N-1 and human umbilical endothelial cells (HUVECs), and NOTCH3 knockdown in NHDFs using siRNA, demonstrated that HO1-N-1 cells significantly promoted tube formation dependent on NOTCH3-expression in NHDFs. Moreover, NOTCH3 expression in CAFs was related to poor prognosis of the OSCC patients. This work provides a new insight into the role of Notch signaling in CAFs associated with tumor angiogenesis and the possibility of NOTCH3-targeted molecular therapy in OSCCs.

Tumour-associated macrophages are recruited and differentiated in the neoplastic stroma of oral squamous cell carcinoma

To confirm our hypothesis that macrophages recruited to fight against oral squamous cell carcinoma (SCC) invasion are functionally differentiated within neoplastic stromata, we analysed arrangements of macrophage subtypes and cancer-associated fibroblasts (CAFs) in their association with blood vasculatures in the neoplastic stroma. Surgical specimens of oral SCC were immunohistochemically examined for macrophage phenotypes (CD68, CD163, and CD204) and stromal environments (perlecan, connexin 43, and CD31). Human monocytes were co-cultured with ZK-1 cells of oral SCC origin in different culture conditions. SCC stromata were divided into two types: fascicular (fibroblast-rich) and reticular (perlecan-rich). Regardless of stromal types, CD68 positive (+)/CD163+/CD204+ macrophages were recruited when blood vessels were abundant. Connexin 43+ fibroblasts were enriched in the fascicular stroma, where blood vessels were depleted. In co-culture experiments, monocytes, in the presence of ZK-1 cells, showed TNF-α(low)/IL-12(low) and IL-10(high)/VEGF(high)/MMP-9(high) with increased expression levels for fibronectin and perlecan. With direct contact with monocytes, SCC cells also expressed CD68 and CD163. SCC stromata were characterised by CD163+/CD204+ tumour-associated macrophages (TAMs) and connexin 43+ CAFs. TAMs are differentiated from monocytes by the physical contact with oral SCC cells in the perlecan-rich neoplastic stroma, which is also induced by the cross-talk between SCC cells and stromal cells including TAMs.

High Numbers of Stromal Cancer-Associated Fibroblasts Are Associated With a Shorter Survival Time in Cats With Oral Squamous Cell Carcinoma

Cancer-associated fibroblasts (CAFs) are fibroblastic cells that express α-smooth muscle actin and have been identified in the stroma of numerous epithelial tumors. The presence of CAFs within the tumor stroma has been associated with a poorer prognosis in some human cancers, including oral squamous cell carcinomas (SCCs). Cats frequently develop oral SCCs, and although these are generally highly aggressive neoplasms, there is currently a lack of prognostic markers for these tumors. The authors investigated the prognostic value of the presence of CAFs within the stroma of oral SCC biopsy specimens from 47 cats. In addition, several epidemiologic, clinical, and histologic variables were also assessed for prognostic significance. A CAF-positive stroma was identified in 35 of 47 SCCs (74.5%), and the median survival time (ST) of cats with CAF-positive SCCs (35 days) was significantly shorter than that of cats with CAF-negative SCCs (48.5 days) (P = .031). ST was also associated with the location of the primary tumor (P = .0018): the median ST for oropharyngeal SCCs (179 days) was significantly longer than for maxillary (43.5 days; P = .047), mandibular (42 days; P = .022), and sublingual SCCs (22.5 days; P = .0005). The median ST of sublingual SCCs was also shorter compared with maxillary SCCs (P = .0017). Furthermore, a significant association was identified between site and the presence of stromal CAFs (P = .025). On the basis of this retrospective study, evaluating the tumor stroma for CAFs in feline oral SCC biopsy specimens may be of potential prognostic value.

Secretome profiling of oral squamous cell carcinoma-associated fibroblasts reveals organization and disassembly of extracellular matrix and collagen metabolic process signatures

An important role has been attributed to cancer-associated fibroblasts (CAFs) in the tumorigenesis of oral squamous cell carcinoma (OSCC), the most common tumor of the oral cavity. Previous studies demonstrated that CAF-secreted molecules promote the proliferation and invasion of OSCC cells, inducing a more aggressive phenotype. In this study, we searched for differences in the secretome of CAFs and normal oral fibroblasts (NOF) using mass spectrometry-based proteomics and biological network analysis. Comparison of the secretome profiles revealed that upregulated proteins involved mainly in extracellular matrix organization and disassembly and collagen metabolism. Among the upregulated proteins were fibronectin type III domain-containing 1 (FNDC1), serpin peptidase inhibitor type 1 (SERPINE1), and stanniocalcin 2 (STC2), the upregulation of which was validated by quantitative PCR and ELISA in an independent set of CAF cell lines. The transition of transforming growth factor beta 1 (TGF-β1)-mediating NOFs into CAFs was accompanied by significant upregulation of FNDC1, SERPINE1, and STC2, confirming the participation of these proteins in the CAF-derived secretome. Type I collagen, the main constituent of the connective tissue, was also associated with several upregulated biological processes. The immunoexpression of type I collagen N-terminal propeptide (PINP) was significantly correlated in vivo with CAFs in the tumor front and was associated with significantly shortened survival of OSCC patients. Presence of CAFs in the tumor stroma was also an independent prognostic factor for OSCC disease-free survival. These results demonstrate the value of secretome profiling for evaluating the role of CAFs in the tumor microenvironment and identify potential novel therapeutic targets such as FNDC1, SERPINE1, and STC2. Furthermore, type I collagen expression by CAFs, represented by PINP levels, may be a prognostic marker of OSCC outcome.

Immunohistochemical expression of matrix metalloproteinase-1, matrix metalloproteinase-2 and matrix metalloproteinase-9, myofibroblasts and Ki-67 in actinic cheilitis and lip squamous cell carcinoma

Matrix metalloproteinases (MMPs), myofibroblasts (MFs) and epithelial proliferation have key roles in neoplastic progression. In this study immunoexpression of MMP-1, MMP-2 and MMP-9, presence of MFs and the epithelial proliferation index were investigated in actinic cheilitis (AC), lip squamous cell carcinoma (LSCC) and mucocele (MUC). Thirty cases of AC, thirty cases of LSCC and twenty cases of MUC were selected for immunohistochemical investigation of the proteins MMP-1, MMP-2, MMP-9, α-smooth muscle actin (α-SMA) and Ki-67. The MMP-1 expression in the epithelial component was higher in the AC than the MUC and LSCC. In the connective tissue, the expression was higher in the LSCC. MMP-2 showed lower epithelial and stromal immunostaining in the LSCC when compared to the AC and MUC. The epithelial staining for MMP-9 was higher in the AC when compared to the LSCC. However, in the connective tissue, the expression was lower in the AC compared to other lesions. The cell proliferation rate was increased in proportion to the severity of dysplasia in the AC, while in the LSCC it was higher in well-differentiated lesions compared to moderately differentiated. There were no statistically significant differences in number of MFs present in the lesions studied. The results suggest that MMPs could affect the biological behaviour of ACs and LSCCs inasmuch as they could participate in the development and progression from premalignant lesions to malignant lesions.

Staphylococcus aureus strains associated with food poisoning outbreaks in France: comparison of different molecular typing methods, including MLVA

Staphylococcal food poisoning outbreaks (SFPOs) are frequently reported in France. However, most of them remain unconfirmed, highlighting a need for a better characterization of isolated strains. Here we analyzed the genetic diversity of 112 Staphylococcus aureus strains isolated from 76 distinct SFPOs that occurred in France over the last 30 years. We used a recently developed multiple-locus variable-number tandem-repeat analysis (MLVA) protocol and compared this method with pulsed field gel electrophoresis (PFGE), spa-typing and carriage of genes (se genes) coding for 11 staphylococcal enterotoxins (i.e., SEA, SEB, SEC, SED, SEE, SEG, SEH, SEI, SEJ, SEP, SER). The strains known to have an epidemiological association with one another had identical MLVA types, PFGE profiles, spa-types or se gene carriage. MLVA, PFGE and spa-typing divided 103 epidemiologically unrelated strains into 84, 80, and 50 types respectively demonstrating the high genetic diversity of S. aureus strains involved in SFPOs. Each MLVA type shared by more than one strain corresponded to a single spa-type except for one MLVA type represented by four strains that showed two different-but closely related-spa-types. The 87 enterotoxigenic strains were distributed across 68 distinct MLVA types that correlated all with se gene carriage except for four MLVA types. The most frequent se gene detected was sea, followed by seg and sei and the most frequently associated se genes were sea-seh and sea-sed-sej-ser. The discriminatory ability of MLVA was similar to that of PFGE and higher than that of spa-typing. This MLVA protocol was found to be compatible with high throughput analysis, and was also faster and less labor-intensive than PFGE. MLVA holds promise as a suitable method for investigating SFPOs and tracking the source of contamination in food processing facilities in real time.

Evaluation of myofibroblasts in oral squamous cell carcinoma using H1 calponin: An immunohistochemical study

BACKGROUND

Oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral mucosa. Stromal myofibroblasts play an important role in tumor invasion and metastasis, due to its ability to modify the extracellular matrix. The purpose of this study was to evaluate and compare the presence of myofibroblasts in normal mucosa, early invasive carcinoma and different grades of OSCC.

MATERIALS AND METHODS

The study included the archival tissues of 18 OSCC of well, moderate and poorly differentiated grades, three early invasive carcinomas and five normal mucosa. Myofibroblasts were identified by immunohistochemical detection of h1 calponin.

RESULTS

The percentage and intensity of h1 calponin were examined and positive immunostaining was observed in the myofibroblasts of all SCCs and early invasive carcinomas; however, these cells did not stain in the normal epithelium specimens. The presence of myofibroblasts was significantly higher in invasive pattern of OSCCs compared to normal mucosa cases (P < 0.070). A significant difference was not observed between the different grades of OSCC (P ≤ 0.812).

CONCLUSION

These findings show the presence of myofibroblasts in OSCC but not in normal mucosa, suggesting that the genetically altered epithelium (carcinomatous epithelium) may have an inductive effect on the adjacent stroma to produce myofibroblasts. Also transdifferentiation of myofibroblasts is induced somewhere in the invasive stage of SCC irrespective of the epithelial cell differentiation.

Stromal myofibroblasts in potentially malignant and malignant lesions of the oral cavity

Previous studies have demonstrated that myofibroblasts in the adjacent stroma are involved in the development and progression of malignant tumors. The aim of this study was to investigate the involvement of myofibroblasts in the progression of oral squamous cell carcinomas (OSCCs) by determining myofibroblast density in potentially malignant and malignant oral lesions. A total of 69 potentially malignant oral lesions (leukoplakias with mild, moderate or severe dysplasia), 90 OSCCs (well-, moderately and poorly differentiated), eight oral verrucous carcinomas and 29 fibrous hyperplasias were examined for the presence of myofibroblasts using immunohistochemical detection of isoform α of smooth muscle actin. Myofibroblasts were not identified in the adjacent stroma of fibrous hyperplasias and potentially malignant oral lesions, whereas 59.8% of the oral carcinomas exhibited myofibroblasts in various densities. The density was significantly higher in moderately and poorly differentiated OSCCs when compared with well-differentiated tumors (P=0.04 and P=0.007, respectively). In verrucous carcinomas, the specific variant of well-differentiated OSCC, stromal myofibroblasts were not detected. The results of the present study demonstrated that immunodetection of myofibroblasts does not aid with the determination of the malignant transformation potential of oral dysplasias, although moderately and poorly differentiated tumors exhibited a significantly higher density of myofibroblasts. The results reinforce the hypothesis that myofibroblasts may contribute to oral tumorigenesis, indicating that verification and monitoring of such may serve as a putative marker of OSCC behavior.

BMP-2 promotes oral squamous carcinoma cell invasion by inducing CCL5 release

Bone morphogenetic protein-2 (BMP-2)-containing bone grafts are useful regenerative materials for oral and maxillofacial surgery; however, several in vitro and in vivo studies previously reported cancer progression-related adverse effects caused by BMP-2. In this study, by quantifying the rhBMP-2 content released from bone grafts, the rhBMP-2 concentration that did not show cytotoxicity in each cell line was determined and applied to the in vitro monoculture or coculture model in the invasion assay. Our results showed that 1 ng/ml rhBMP-2, while not affecting cancer cell viability, significantly increased the invasion ability of the cancer cells cocultured with fibroblasts. Cocultured medium with rhBMP-2 also contained increased levels of matrix metalloproteinases. rhBMP-2-treated cocultured fibroblasts did not show a prominent difference in mRNA expression profile. Some cytokines, however, were detected in the conditioned medium by a human cytokine antibody array. Among them, the cancer invasion-related factor CCL5 was quantified by ELISA. Interestingly, CCL5 neutralizing antibodies significantly reduced the invasion of oral cancer cells. In conclusion, our results suggest that 1 ng/ml rhBMP-2 may induce invasion of oral squamous cell carcinoma (OSCC) cells by CCL5 release in coculture models. Therefore, we propose that a careful clinical examination before the use of rhBMP-2-containing biomaterials is indispensable for using rhBMP-2 treatment to prevent cancer progression.

Myofibroblast presence in apparently normal mucosa adjacent to oral squamous cell carcinoma associated with chronic tobacco/areca nut use: evidence for field cancerization

OBJECTIVE

Myofibroblasts are primary cellular components of activated tumor stroma, associated with poor prognosis in oral squamous cell carcinoma (OSCC). However, their role in field cancerization has not been addressed. This study aims to evaluate the presence of myofibroblasts in patient-matched histologically normal mucosa adjacent to oral squamous cell carcinoma (HNMAOSCC) and OSCC tissues.

MATERIALS AND METHODS

Fifty patient-matched tissues of OSCC and HNMAOSCC associated with chronic areca nut/tobacco use were subjected to immunohistochemistry using α-SMA for detection of myofibroblasts. Normal oral mucosa (n = 15) were stained as controls.

RESULTS

The number of α-SMA stained myofibroblasts in OSCC and HNMAOSCC were significantly increased as compared to that of the normal controls (p < 0.001). Further, a significant correlation was established for the presence of myofibroblasts in the stroma of OSCC and HNMAOSCC.

CONCLUSIONS

Myofibroblasts are an early stromal change in the HNMAOSCC, highlighting the possible role of myofibroblasts as likely mediators for field cancerization and their potential use as a field effect marker.

Evaluation of in situ expression of effector and regulatory cytokines, TLR, galectins and matrix metalloproteinases in oral manifestations of paracoccidioidomycosis

BACKGROUND

Although the pathophysiology of paracoccidioidomycosis (PCM) is not completely understood, the study of immune response against fungus has provided insight into understanding the natural course of the disease and its clinical manifestations, hence contributing to the development of preventive measures and treatment proposals. The aim of this study was to evaluate the histopathological and immunological aspects involved in the role of different effector and regulatory responses, as well as the correlation between the TLRs, Galectins, Matrix Metalloproteinases and cytoplasmic proteases of mast cells in this infection.

METHODS

Sixteen biopsy specimens with oral lesions of chronic PCM, as well as 13 sections of normal oral mucosa were analyzed. Histopathological and immunological aspects involved in the role of different effector and regulatory responses were evaluated. Indirect immunohistochemistry was performed for IL-17, IL-10, IL-4, TGF-β, FoxP3, Gal-1, Gal-3, Gal-9, TLR-2, TLR-4, MMP-3 and MMP-9, as well as for chymase and tryptase for mast cells identification. Fibrosis was quantified using Picrosirius.

RESULTS

There was a significant increase in the area of fibrosis and in the number of cells expressing IL-10, IL-4, IL-17, FoxP3, Gal-3, TLR-2, MMP3 and MMP9 in patients with PCM in comparison with patients in the group control. There was no difference in the expression of TGF-β, TLR-4, Gal-1 or Gal-9. Mast cells number was found to be significantly lower in oral chronic PCM when compared to control samples after quantification of mast cells and expression of chymase and tryptase. PCM granulomas were classified to the morphological aspects in organized ou non-organized. Expression of IL-4 in non-organized granulomas was significantly higher.

CONCLUSION

The proteins studied herein appear to play an important role in the development and maintenance of oral lesions of PCM, as well as in the processes of development and progression of lesions caused by the fungus and by the immune response associated with the infection.

Stromal myofibroblasts in squamous cell carcinoma of the tongue in young patients - a multicenter collaborative study

OBJECTIVE

The purpose of this study was to evaluate the presence of myofibroblasts, frequently associated with a more aggressive neoplastic behavior, in oral tongue squamous cell carcinoma (TSCC) of young patients and to compare with the distribution observed in older patients.

STUDY DESIGN

Tumor samples from 29 patients younger than 40 years old affected by TSCC were retrieved and investigated for the presence of stromal myofibroblasts by immunohistochemical reactions against α smooth muscle actin, and the results obtained were compared to TSCC cases affecting older patients.

RESULTS

No positive reaction could be found in the stromal areas devoid of neoplastic tissue, whereas myofibroblasts were present in 58.6% of the lesions in young patients and in 75.9% of the older ones. No significant difference was found when comparing the invasive front and the overall stroma of both groups, and no correlation could be obtained with stromal α smooth muscle actin expression, higher tumor grades or clinical stage (P > .05).

CONCLUSION

There was no significant difference between the presence of stromal myofibroblasts of TSCC affecting young and old individuals.

Myofibroblasts in oral lesions: A review

Myofibroblasts (MFs) are modified fibroblasts that express features of smooth muscle differentiation and were first observed in granulation tissue during wound healing. These cells play a key role in physiologic and pathologic processes like wound healing and tumorigenesis. The presence of MFs has been reported in normal oral tissues and pathologic conditions like reactive lesions, benign tumors, locally aggressive tumors and malignancies affecting the oral cavity. This article briefly reviews the important hallmarks related to the discovery, characterization and tissue distribution of MFs in oral health and disease.

Ki-67, TGF-β1, and elastin content are significantly altered in lip carcinogenesis

Epithelial changes observed in actinic cheilitis (AC) and lower lip squamous cell carcinoma (LLSCC) have been studied using different markers in order to observe diagnostic and prognostic factors for both lesions. The aim of the present study was to analyze Ki-67, TGF-β1, and elastin content in AC and LLSCC to determine the possible role of these proteins in lip carcinogenesis. Medical records of 29 cases of AC and 53 cases of LLSCC were analyzed. Lesions were classified according histological pattern and submitted to immunostaining for Ki-67, TGF-β1, and elastin. Different percentages of Ki-67-positive cells were found in AC depending on the degree of epithelial dysplasia (p < 0.01). An association was also found between the percentage of Ki-67-positive cells and tumor grade in LLSCC (p < 0.01). An inverse correlation was found between Ki-67 and TGF-β1 in AC and LLSCC (p < 0.01). Elastosis was thinner and more discontinuous in LLSCC in comparison to AC, and this difference in the elastin immunolabeling pattern was statistically significant between groups (p < 0.01). The present findings indicate that changes in Ki-67 and TGF-β1 content contribute to lip carcinogenesis. Furthermore, elastin content reflects changes in the extracellular matrix in both AC and LLSCC.

Activin A immunoexpression as predictor of occult lymph node metastasis and overall survival in oral tongue squamous cell carcinoma

BACKGROUND

The presence of regional lymph node metastasis has an important impact on clinical management and prognostication of patients with oral tongue squamous cell carcinoma (SCC). Approximately 30% to 50% of patients with oral tongue SCC have regional metastasis at diagnosis, but the limited sensibility of the current diagnostic methods used for neck staging does not allow detection of all cases, leaving a significant number of undiagnosed metastasis (occult lymph node metastasis). In this study, we evaluated whether clinicopathologic features and immunohistochemical detection of carcinoma-associated fibroblasts (CAFs) and activin A could be predictive markers for occult lymph node metastasis in oral tongue SCC.

METHODS

One hundred ten patients with primary oral tongue SCC, who were classified with early stage tumor (stage I and II) and received surgical treatment with elective neck dissection, were enrolled in the study.

RESULTS

Among all examined features, only high immunohistochemical expression of activin A was significantly associated with presence of occult lymph node metastasis (p = .006). Multivariate survival analysis using the Cox proportional hazard model showed that the expression of activin A was an independent marker of reduced overall survival with a 5-year survival of 89.7% for patients with low expression compared to 76.5% for those with high expression (hazard ratio [HR], 2.44; 95% confidence interval [CI], 1.55-3.85; p = .012).

CONCLUSION

Our results demonstrated that immunodetection of activin A can be useful for prognostication of oral tongue SCC, revealing patients with occult lymph node metastasis and lower overall survival.

A role for cancer-associated fibroblasts in inducing the epithelial-to-mesenchymal transition in human tongue squamous cell carcinoma

OBJECTIVES

Lymph node metastasis is a prominent clinical feature of tongue squamous cell carcinoma (TSCC) and is associated with a higher mortality rate. Carcinoma-associated fibroblasts (CAFs), a major component of the tumor microenvironment (TME), play an important role in tumor progression, and are associated with a poor prognosis. The aim of this study was to examine the role of CAFs in promoting the invasion of TSCC through the epithelial-to-mesenchymal transition (EMT).

MATERIALS AND METHODS

A series of matched CAF and normal fibroblast (NF) pairs were assessed for cell morphology and for the expression of alpha smooth muscle actin (α-SMA), stromal cell-derived factor-1 (SDF1), fibroblast-activating protein (FAP), vimentin, and cytokeratin (CK) markers. Transwell assays, Western blot analysis, reverse transcription-PCR, and immunofluorescence staining were used to assess the role of CAFs, as compared to that of NFs, in promoting proliferation, migration, invasion, and EMT in TSCC.

RESULTS

Both CAF and NF primary cultures expressed vimentin but not CK. CAFs showed significantly higher α-SMA protein levels, SDF1 secretion, and mRNA levels of α-SMA, SDF1, and FAP. We also found that co-culture with CAFs enhanced the proliferation and invasion of SCC9 cells. Moreover, co-culture with CAFs induced upregulation of the EMT markers fibronectin and vimentin, downregulation of E-cadherin, and enhanced invasion in SCC9 cells.

CONCLUSION

These results suggest that CAFs induce EMT marker expression and functional changes in TSCCs.

Effects of activated fibroblasts on phenotype modulation, EGFR signalling and cell cycle regulation in OSCC cells

Crosstalk between carcinoma associated fibroblasts (CAFs) and oral squamous cell carcinoma (OSCC) cells is suggested to mediate phenotype transition of cancer cells as a prerequisite for tumour progression, to predict patients' outcome, and to influence the efficacy of EGFR inhibitor therapies. Here we investigate the influence of activated fibroblasts as a model for CAFs on phenotype and EGFR signalling in OSCC cells in vitro. For this, immortalised hTERT-BJ1 fibroblasts were activated with TGFβ1 and PDGFAB to generate a myofibroblast or proliferative phenotype, respectively. Conditioned media (FCMTGF, FCMPDGF) were used to stimulate PE/CA-PJ15 OSCC cells. Results were compared to the effect of conditioned media of non-stimulated fibroblasts (FCMB). FCMTGF stimulation leads to an up-regulation of vimentin in the OSCC cells and an enhancement of invasive behaviour, indicating EMT-like effects. Similarly, FCMTGF≫FCMPDGF induced up-regulation of EGFR, but not of ErbB2/ErbB3. In addition, we detected an increase in basal activities of ERK, PI3K/Akt and Stat3 (FCMTGF>FCMPDGF) accompanied by protein interaction of vimentin with pERK. These effects are correlated with an increased proliferation. In summary, our results suggest that the activated myofibroblast phenotype provides soluble factors which are able to induce EMT-like phenomena and to increase EGFR signalling as well as cell proliferation in OSCC cells. Our results indicate a possible influence of activated myofibroblasts on EGFR-inhibitor therapy. Therefore, CAFs may serve as promising novel targets for combined therapy strategies.

Intratumoral hepatic stellate cells as a poor prognostic marker and a new treatment target for hepatocellular carcinoma

Hepatic stellate cells (HSCs), a specialized stromal cytotype in the liver, have been demonstrated to actively contribute to hepatocellular carcinoma (HCC) development. However, the previous studies were performed using HSC cell lines, and the prognostic value of intratumoral HSCs (tHSCs) was unclear. Here we isolated tHSCs from fresh human HCC tissues, and analyzed the abilities of tHSCs to promote HCC progression by using in vitro assays for cell viability, migration and invasion as well as epithelial-mesenchymal transition (EMT) phenotype. 252 HCC patients who underwent hepatectomy were enrolled for analysis of tHSCs and E-cadherin expression in tumor tissues, and 55 HCC patients for analysis of tHSCs in tumor tissues and circulating tumor cells (CTCs) in blood. Prognostic factors were then identified. The results showed that coculture of tHSCs with HCC cells had a stronger effect on HCC cell viability, migration and invasion, accompanied with the acquisition of epithelial-mesenchymal transition (EMT) phenotype. In vivo cotransplantation of HCC cells with tHSCs into nude mice more efficiently promoted tumor formation and growth. Icaritin, a known apoptosis inducer of HSCs, was demonstrated to effectively inhibit tHSC proliferation in vitro and tHSC-induced HCC-promoting effects in vivo. Clinical evidence indicated that tHSCs were rich in 45% of the HCC specimens, tHSC-rich subtypes were negatively correlated either with E-cadherin expression in tumor tissues (r = -0.256, p < 0.001) or with preoperative CTCs in blood (r = -0.287, p = 0.033), and were significantly correlated with tumor size (p = 0.027), TNM staging (p = 0.018), and vascular invasion (p = 0.008). Overall and recurrence-free survival rates of tHSC-rich patients were significantly worse than those for tHSC-poor patients. Multivariate analysis revealed tHSC-rich as an independent factor for overall and recurrence-free survival. In conclusion, tHSCs provide a promising prognostic biomarker and a new treatment target for HCC.

Stromal myofibroblasts in nonmetastatic and metastatic oral squamous cell carcinoma: An immunohistochemical study

BACKGROUND AND AIMS

Myofibroblasts are one of the important components of the tumor microenvironment which could possibly play an important role in tumor progression. The purpose of this study was to compare the presence of α-smooth muscle actin (α-SMA) and CD34 positive fibroblasts in nonmetastatic and metastatic oral squamous cell carcinoma and to evaluate their role in tumor metastasis.

MATERIALS AND METHODS

Ten cases each of histologically proven metastatic and nonmetastatic oral squamous cell carcinoma formed the study group. The tissue sections were stained immunohistochemically for α-SMA and CD34. The stromal spindle cells positive for these markers in the study groups were counted and compared.

RESULTS

α-SMA positive cases were more in the metastatic group and CD34 positive cases were found to be more in the nonmetastatic tumors.

CONCLUSIONS

Though difference in the staining pattern was statistically nonsignificant, the inverse relationship between α-SMA and CD34 positive cells is indicative of dynamic nature and the influence of tumor stroma in tumor progression and metastasis.

Silencing of miR-148a in cancer-associated fibroblasts results in WNT10B-mediated stimulation of tumor cell motility

The tumor microenvironment has an important role in cancer progression. Here we show that miR-148a is downregulated in 15 out of 16 samples (94%) of cancer-associated fibroblasts (CAFs) compared with matched normal tissue fibroblasts (NFs) established from patients with endometrial cancer. Laser-capture microdissection of stromal cells from normal tissue and endometrial cancer confirmed this observation. Treatment of cells with 5-aza-deoxycytidine stimulated the expression of miR-148a in the majority of CAFs implicating DNA methylation in the regulation of miR-148a expression. Investigation of miR-148a function in fibroblasts demonstrated that conditioned media (CM) from CAFs overexpressing miR-148a significantly impaired the migration of five endometrial cancer cell lines without affecting their growth rates in co-culture experiments. Among predicted miR-148a target genes are two WNT family members, WNT1 and WNT10B. Activation of the WNT/β-catenin pathway in CAFs was confirmed by microarray analysis of gene expression and increased activity of the SuperTOPFlash luciferase reporter. We found elevated levels of WNT10B protein in CAFs and its level decreased when miR-148a was re-introduced by lentiviral infection. The 3'-UTR of WNT10B, cloned downstream of luciferase cDNA, suppressed luciferase activity when co-expressed with miR-148a indicating that WNT10B is a direct target of miR-148a. In contrast to the effect of miR-148a, WNT10B stimulated migration of endometrial cancer cell lines. Our findings have defined a molecular mechanism in the tumor microenvironment that is a novel target for cancer therapy.

Association of tumor-associated fibroblasts with progression of hepatocellular carcinoma

Interaction between tumor and stromal cells plays an important role in cancer progression. The aim of this study was to explore the effects of tumor-associated fibroblasts on regulation of hepatocellular carcinoma (HCC) progression. Sixty-five cases of HCC and the corresponding normal liver tissues were recruited for immunohistochemical assessment of α-smooth muscle actin (α-SMA) expression, a biomarker for activated fibroblasts. Clinicopathological data were also collected from HCC patients for association with α-SMA expression. Primary cell culture of fibroblasts from HCC tissues was used to generate conditioned medium for testing the effect on regulation of HCC cell migration capacity in the transwell cell migration assay. α-SMA protein was expressed in 84.0 % (21 out 25 cases) of the fibroblasts from the metastatic HCCs, 45 % (18/40) from HCCs without metastasis, and 19.2 % (5/26) from normal liver tissues, difference of which was statistically significant (P < 0.01). The expression of α-SMA protein in HCC tissues was associated with tumor thrombosis, poor pathology grade, advanced clinical stages, and lymph node metastasis. The conditioned medium from the primary cultured fibroblasts with α-SMA expression significantly promoted the migration capacity of HCC Hep3B cells compared to the heat-inactivated conditioned medium. The data from the current study demonstrated that expression of α-SMA protein in HCC fibroblasts associated with tumor metastasis and advanced clinical stages and that the conditioned medium from α-SMA-positive fibroblasts enhanced HCC cell migration. This study indicates that α-SMA protein might serve as a biomarker to predict HCC progression.

Carcinoma-associated fibroblasts, its implication in head and neck squamous cell carcinoma: a mini review

The communication between tumor stromal and parenchymal cells provides an insight to tumor progression. One of the main elements of the stroma, a major contributor to the extracellular environment of tumors, is carcinoma-associated fibroblasts. They can originate from either normal fibroblasts in the immediate vicinity of the tumor or from circulating bone marrow-derived mesenchymal stem cells. These myofibroblasts can arise locally from an endothelial-mesenchymal transformation at the invasive edge of the cancer and are physically associated with carcinoma cells, that is, in the development of high-grade malignancies and poor prognosis. These carcinoma-associated fibroblasts feed the epithelial tumor cells in a host-parasite relationship establishing its role in head and neck squamous cell carcinoma progression.

Myofibroblasts and transforming growth factor-beta1 in reactive gingival overgrowths

Objectives

The purpose of this study was to evaluate the oral health-related quality of life of patients treated with implant-supported mandibular overdentures and to compare the attachment systems used.

Material and Methods

The presence of myofibroblasts as well as transforming growth factor-beta1 was examined in twenty cases of fibrous epulis and 22 ossifying fibrous epulis, using immunohistochemistry.

Results

Myofibroblasts positive for alpha smooth muscle actin and vimentin but negative to desmin were found in 20% and 45% in fibrous epulis and ossifying fibrous epulis, respectively. Myofibroblasts were distributed in areas with and without inflammatory infiltration and their presence in inflammatory areas was not related with the degree of inflammatory infiltration. A percentage of 21 - 60% of fibroblasts and chronic inflammatory cells expressed transforming growth factor-beta1 in all cases.

Conclusions

These data suggest that transforming growth factor-beta1 and myofibroblasts contribute to the formation of collagenous connective tissue in fibrous epulis and ossifying fibrous epulis. Myofibroblasts are mainly presented in ossifying fibrous epulis than in fibrous epulis. It seems to be no relationship between the presence of myofibroblasts and the degree of inflammatory infiltration of the lesions.

Myofibroblasts and their relationship with oral squamous cell carcinoma

Myofibroblasts are hybrid-phenotype differentiated cells in between fibroblasts and smooth muscle cells. Due to their contractile features and ability to synthesize extracellular matrix components, cytokines, proteases, and proangiogenic factors, myofibroblasts have been implicated in the pathogenesis of fibrocontractive diseases and in the progression of many tumors, including oral squamous cell carcinoma (SCC).

OBJECTIVE

To perform a literature review on the origin of myofibroblasts, their main morpho-physiological and immunohistochemical aspects, and to discuss the correlations with oral SCC.

METHOD

A search was made on the PubMed database to select the main papers in the literature in English related to the subject, published between January 1991 and December 2011.

CONCLUSION

Myofibroblasts are an important component of the stroma of oral SCCs, although they are not present in all tumors. Abundant presence of myofibroblasts may be associated with local disease recurrence and decreased patient survival. However, given the relatively limited number of studies on the subject, further research is needed to clarify the molecular mechanisms by which myofibroblasts influence the biological behavior of oral SCC.

The tumor microenvironment contribution to development, growth, invasion and metastasis of head and neck squamous cell carcinomas

Head and neck squamous cell carcinoma (HNSCC) is a complex tissue that contains tumor cells and the surrounding stroma, which is populated by different types of mesenchymal cells and the extracellular matrix (ECM). Collectively, they are referred to as the tumor microenvironment (TME). Recent studies have shown that TME has a more profound influence on the growth and metastasis of HNSCC than was previously appreciated. Because carcinoma-associated fibroblasts (CAFs) are frequently observed in the stroma of the tumor, this review focuses on the potential role of tumor-CAFs interactions in progression of HNSCC. Tumor-CAFs crosstalk enhances the production of growth factors, cytokines, chemokines, matrix metalloproteinases (MMPs), and inflammatory mediators, which eventually facilitates tumor growth. In fact, factors and cells that do not support tumor growth are usually down regulated or mitigated in TME. Therefore TME may determine the fate of the tumors at the site of invasion and metastasis. For tumor cells that survive at these sites, stromal activation may serve to establish a supportive tumor stroma, fostering the outgrowth of the metastatic cells. The concept of tumor-stromal interactions and microenvironmental niche has profound consequences in tumor growth and metastasis and therefore, it's understanding will open up new strategies for the diagnosis, prognosis and therapy of HNSCC.

Quantitative assessment of myofibroblast in severe dysplasia, microinvasion and oral squamous cell carcinoma: an immunohistochemical study

Myofibroblast are essential for the integrity of human body by virtue of its role in wound healing and pathological organ remodeling. Myofibroblast is a universal cellular component in mammalian lesions, but not a typical component of normal untraumatized tissues. Therefore its presence in abundance in case of cancer is a matter of concern. Tumor microenvironment plays a pivotal role in tumor progression. These so called cancer associated fibroblast or myofibroblast are the major components and occur in stromal tissue during carcinogenesis processes. This study is a quantitative assessment of presence and distribution of myofibroblast in severe dysplasia, microinvasion and oral squamous cell carcinoma (OSCC).

KEYWORDS

Myofibroblast, Vimentin, α-SMA, OSCC, Severe dysplasia, Microinvasion. How to cite this article: Kapse SC, Rathod N, Baad R, Mandlik J, Sharma AS, Bommanavar S. Quantitative Assessment of Myofibroblast in Severe Dysplasia, Microinvasion and Oral Squamous Cell Carcinoma: An Immunohistochemical Study. J Contemp Dent Pract 2013;14(1):34-38. Source of support: Nil Conflict of interest: None declared.

Stromal myofibroblasts in oral leukoplakia and oral squamous cell carcinoma

Objectives: Oral leukoplakia (OL) is the main potentially malignant disorder and oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral mucosa. Stromal myofibroblasts play an important role in tumor invasion and metastasis, due to its ability to modify the extracellular matrix. This study aimed to evaluate the presence of stromal myofibroblasts in OL and OSCC. Differences in the presence of myofibroblasts among OL with distinct grades of epithelial dysplasia as well as between histologically high- and low-invasive OSCC were also assessed. Study Design: A total of 30 OL and 41 OSCC from archival formalin-fixed, paraffin-embedded specimens were evaluated. 10 samples of normal oral mucosa were used as a control. Myofibroblasts were identified by immunohistochemical detection of alpha smooth muscle actin and its presence was classified as negative, scanty or abundant. Differences in the presence of myofibroblasts among OL with distinct grades of epithelial dysplasia as well as between high- and low-invasive OSCC were analyzed using the Mann-Whitney test. Results: Myofibroblasts were not detected in normal oral mucosa and OL, whatever its histological grade. In OSCC, the presence of stromal myofibroblasts was classified as negative in 11 (26.8%), scanty in 15 (36.6%), and abundant in 15 samples (36.6%). The presence of stromal myofibroblasts was statistically higher in high-invasive OSCC than in low-invasive OSCC (p<0.05). Conclusions: Stromal myofibroblasts were not detected in OL, indicating that these cells are not important during oral carcinogenesis. Nevertheless, stromal myofibroblasts were heterogeneously detected in OSCC and its presence was higher in tumors with a more diffuse histological pattern of invasion. These findings suggest that myofibroblasts are associated with the creation of a permissive environment for tumor invasion in OSCC.

Key words:Leukoplakia, oral squamous cell carcinoma, myofibroblast.

CCL2 mediates cross-talk between cancer cells and stromal fibroblasts that regulates breast cancer stem cells

Cancer stem cells (CSC) play critical roles in cancer initiation, progression, and therapeutic refractoriness. Although many studies have focused on the genes and pathways involved in stemness, characterization of the factors in the tumor microenvironment that regulate CSCs is lacking. In this study, we investigated the effects of stromal fibroblasts on breast cancer stem cells. We found that compared with normal fibroblasts, primary cancer-associated fibroblasts (CAF) and fibroblasts activated by cocultured breast cancer cells produce higher levels of chemokine (C-C motif) ligand 2 (CCL2), which stimulates the stem cell-specific, sphere-forming phenotype in breast cancer cells and CSC self-renewal. Increased CCL2 expression in activated fibroblasts required STAT3 activation by diverse breast cancer-secreted cytokines, and in turn, induced NOTCH1 expression and the CSC features in breast cancer cells, constituting a cancer-stroma-cancer signaling circuit. In a xenograft model of paired fibroblasts and breast cancer tumor cells, loss of CCL2 significantly inhibited tumorigenesis and NOTCH1 expression. In addition, upregulation of both NOTCH1 and CCL2 was associated with poor differentiation in primary breast cancers, further supporting the observation that NOTCH1 is regulated by CCL2. Our findings therefore suggest that CCL2 represents a potential therapeutic target that can block the cancer-host communication that prompts CSC-mediated disease progression.

Comparison of myofibroblasts expression in oral squamous cell carcinoma, verrucous carcinoma, high risk epithelial dysplasia, low risk epithelial dysplasia and normal oral mucosa

The aim was to evaluate and compare the presence of myofibroblasts in oral squamous cell carcinoma (OSCC), verrucous carcinoma (VC), high-risk epithelial dysplasia (HRED), low-risk epithelial dysplasia (LRED), and normal oral mucosa (NOM). The study consisted of 37 OSCC, 15 VC, 15 HRED, 15 LRED and 15 NOM. α-smooth muscle actin (α-SMA) antibody was used to identify myofibroblasts. The α-SMA expression was not observed in NOM and LRED. The α-SMA was expressed in 97.29% of OSCC, 86.66% of VC, 46.66 % of HRED. The α-SMA expression was significantly higher in OSCC than VC (p = 0.023) and HRED (p < 0.000). The α-SMA expression was significantly higher in VC than HRED (p = 0.043). Myofibroblastic expression, as highlighted by α-SMA, is undetectable in NOM and LRED but increases as the disease progresses from potentially malignant disorders, as HRED to VC to invasive OSCC. Thus, proliferation of myofibroblasts may be used as a stromal marker of oral premalignancy and malignancy.

Cancer-associated fibroblasts and CD163-positive macrophages in oral squamous cell carcinoma: their clinicopathological and prognostic significance

BACKGROUND

Stromal cells are believed to affect cancer invasion and metastasis. The purpose of this study was to evaluate the distribution of cancer-associated fibroblasts (CAFs) and the incidence of tumor-associated macrophages (TAMs) in oral squamous cell carcinoma (OSCC), focusing on clinicopathological factors and patient prognosis, as well as cancer invasion.

METHODS

The study included 108 patients with OSCC. Anti-α-smooth muscle actin, CD68, and CD163 antibodies were used to identify CAFs and TAMs. CAFs were divided into 4 grades on the basis of staining intensity: negative (0), scanty (1), focal (2), and abundant (3). The most intensive areas of macrophage concentration in each tumor invasive stroma were also evaluated.

RESULTS

The cancer specimens were divided into Grade 0/1, Grade 2, and Grade 3 on the basis of CAF grade. In addition, they were divided into low- and high-grade groups on the basis of the number of CD68-positive and CD163-positive macrophages. The latter were significantly increased in the Grade 2 CAF group compared to the Grade 0/1 group (P = 0.009). Kaplan-Meier and multivariate survival analyses revealed that Grade 2 CAFs (P = 0.003) and high CD163-positive macrophage levels (P = 0.007) significantly correlated with a poor outcome in patients with OSCC, and that a high CD163-positive macrophage level was a significant and an independent prognostic factor (P = 0.045).

CONCLUSIONS

Cancer-associated fibroblasts and CD163-positive macrophages may be potential prognostic predictors of OSCC.