The expression levels and the differential expression of transforming growth factor-β receptors in dermatofibroma and dermatofibrosarcoma protuberans

Increased Occurrence of Cutaneous Leiomyomas and Dermatofibromas in Patients with Uterine Leiomyomas without Fumarate Hydratase Gene Mutations

Leiomyomas are smooth muscle-derived benign neoplasms that can affect all organs, most frequently in the uterus. Fumarate hydratase gene (FH) mutation is characterised by an autosomal dominant disease with increased occurrence of renal tumours, but also by cutaneous (CLs) and uterine leiomyomas (ULs). So far, an increased occurrence of skin tumours in non-mutated patients with ULs has not been verified. To this aim, a case-group of women who were FH non-mutated patients surgically treated for ULs (n = 34) was compared with a control-group (n = 37) of consecutive age-matched healthy women. The occurrence of skin neoplasms, including CLs and dermatofibromas (DFs), was evaluated. Moreover, the microscopic features of FH non-mutated skin tumours were compared with those of an age-matched population group (n = 70) who presented, in their clinical history, only one type of skin tumour and no ULs. Immunohistochemical and in vitro studies analysed TGFβ and vitamin D receptor expression. FH non-mutated patients with ULs displayed a higher occurrence of CLs and DFs (p < 0.03 and p < 0.001), but not of other types of skin tumours. Immunohistochemistry revealed a lower vitamin D receptor (VDR) expression in CLs and DFs from the ULs group compared with those from the population group (p < 0.01), but a similar distribution of TGFβ-receptors and SMAD3. In vitro studies documented that TGFβ-1 treatment and vitamin D3 have opposite effects on α-SMA, TGFβR2 and VDR expression on dermal fibroblast and leiomyoma cell cultures. This unreported increased occurrence of CLs and DFs in FH non-mutated patients with symptomatic ULs with vitamin D deficiency suggests a potential pathogenetic role of vitamin D bioavailability also for CLs and DFs.

Challenging Patterns of Atypical Dermatofibromas and Promising Diagnostic Tools for Differential Diagnosis of Malignant Lesions

Dermatofibroma (DF) or fibrous histiocytoma is one of the most frequent benign cutaneous soft-tissue lesions, characterized by a post-inflammatory tissue reaction associated with fibrosis of the dermis. Clinically DFs have a polymorphous clinical aspect from the solitary, firm, single nodules to multiple papules with a relatively smooth surface. However, multiple atypical clinicopathological variants of DFs have been reported and, therefore, clinical recognition may become challenging, leading to a more burdensome identification and sometimes to misdiagnosis. Dermoscopy is considered an important tool in DFs diagnosis, as it improves diagnostic accuracy for clinically amelanotic nodules. Although typical dermoscopic patterns are most frequently seen in clinical practice, there have also been some atypical variants described, mimicking some underlying recurrent and sometimes harmful skin afflictions. Usually, no treatment is required, although an appropriate work-up may be necessary in specific cases, such as in the presence of atypical variants or a history of recent changes. This narrative review's aim is to summarize current evidence regarding clinical presentation, positive and differential diagnosis of atypical dermatofibromas and also to raise awareness about the importance of specific characteristics of atypical variants to better differentiate them from malignant conditions.

Hyaluronan/RHAMM interactions in mesenchymal tumor pathogenesis: role of growth factors

Fibrosarcoma belongs to the sarcoma cancer group, which are spindle cell malignancies of mesenchymal origin, and owe their name to the predominant cell line that is present within the tumor. The extracellular matrix (ECM) is a complicated structure that surrounds and supports cells within tissues. Its main components are proteoglycans, collagens, glycoproteins, hyaluronan (HA), and several matrix-degrading enzymes. During cancer progression, significant changes can be observed in the structural and mechanical properties of ECM components. The ECM provides a physical scaffold to which tumor cells attach and migrate. Thus, it is required for key cellular events such as cell motility, adhesion, proliferation, invasion, and metastasis. Importantly, fibrosarcomas were shown to have a high content and turnover of ECM components including HA, proteoglycans, collagens, fibronectin, and laminin. In this review, we will focus on the HA component of fibrosarcoma ECM and critically discuss its role and involved mechanisms during fibrosarcoma pathogenesis.

Identification of leukocyte-specific protein 1-positive cells: a clue to the cell of origin and a marker for the diagnosis of dermatofibroma

Background

Dermatofibroma (DF) comprises a heterogeneous group of mesenchymal tumors, with fibroblastic and histiocytic elements present in varying proportions. The cell of origin of DF has been investigated, but remains unclear.

Objective

The present study attempted to investigate the expression of leukocyte-specific protein 1 (LSP1), a marker of fibrocytes, in DF. Additionally, we evaluated the effectiveness of LSP1 in the differential diagnosis of DF from dermatofibrosarcoma protuberans (DFSP).

Methods

Immunohistochemical staining was performed on 20 cases of DF using antibodies against LSP1, CD68, and factor XIIIa (FXIIIa). In addition, the expression of LSP1 and FXIIIa was evaluated in 20 cases of DFSP.

Results

Eighteen of 20 cases (90%) of DF stained positive for LSP1, with variation in the intensity of expression. CD68 was positive in 10 cases (50%), and FXIIIa was expressed in all cases of DF. There were differences between the regional expression patterns of the three markers in individual tumors. In contrast, only 2 of 20 cases of DFSP expressed LSP1, and none of DFSP cases stained positive for FXIIIa.

Conclusion

The LSP1-positive cells in DF could potentially be fibrocyte-like cells. FXIIIa and CD68 expression suggests that dermal dendritic cells and histiocytes are constituent cells of DF. It is known that fibrocytes, dermal dendritic cells and histiocytes are all derived from CD14+ monocytes. Therefore, we suggest that DF may originate from CD14+ monocytes. Additionally, the LSP1 immunohistochemical stain could be useful in distinguishing between DF and DFSP.

Immunohistochemical markers in fibrohistiocytic lesions: factor XIIIa, CD34, S-100 and p75

BACKGROUND

The distinction between dermatofibroma (DF), dermatofibrosarcoma protuberans (DFSP), and other benign and malignant cutaneous spindle cell lesions frequently requires immunohistochemical staining. CD34 and factor XIIIa are the most commonly used immunostains; however, they may exhibit aberrant expression and introduce the potential for misdiagnosis. There is some data supporting that p75 and S100A6 may be additional helpful immunohistochemical markers.

METHODS

We undertook a large case series examining the use of CD34 and factor XIIIa as well as p75 and S100A6 in DF, cellular DF, DFSP, indeterminate fibrohistiocytic lesion, and scar.

RESULTS

As expected, CD34 stained DFSP, although it was usually negative in DF. Factor XIIIa was generally positive in DF and negative in DFSP. There were exceptions in both cases of DF and DFSP. S100A6 was routinely negative in all entities studied. P75 was negative in all cases except DFSP, approximately half of which showed weak and/or patchy positivity.

CONCLUSIONS

We conclude that to date, CD34 and factor XIIIa remain the most reliable immunohistochemical markers for DF and DFSP.

Risk of subsequent primary malignancies after dermatofibrosarcoma protuberans diagnosis: a national study

BACKGROUND

Patients frequently live many years after diagnosis of dermatofibrosarcoma protuberans (DFSP).

OBJECTIVE

We sought to determine the risk of subsequent primary malignancy (SPM) after DFSP diagnosis.

METHODS

Using the Surveillance, Epidemiology, and End Results database (1973-2008) for 3734 patients with DFSP, we compared the risk of developing 14 SPMs (12 most prevalent cancers in the United States plus other nonepithelial and soft tissue) relative to risk in the general population of same sex, race, and age and year of diagnosis.

RESULTS

Patients given the diagnosis of DFSP had an overall increased risk of SPM (observed:expected [O:E], 1.20; 95% confidence intervals [CI], 1.04-1.39), with much of the overall increased risk attributable to increased risk of nonepithelial skin cancer (O:E, 9.94; 95% CI, 3.38-22.30). Specifically, female patients with DFSP were at increased risk of other nonepithelial skin cancer (O:E, 14.50; 95% CI, 3.46-38.98), melanoma (O:E, 2.59; 95% CI, 1.02-5.35), and breast cancer (O:E, 1.44; 95% CI, 1.00-2.00). Male patients were not at increased overall risk (O:E, 1.18; 95% CI, 0.96-1.44) of SPM or at increased risk of any specific malignancy (P > .05) adjusted for multiplicity of t tests.

LIMITATIONS

Surveillance bias may have led to increased rates and earlier detection of primary malignances in patients with DFSP compared with the general population. Individual data that may reveal shared environmental causes of DFSP and SPM were unavailable.

CONCLUSIONS

Patients with DFSP are at increased risk of a number of SPMs.

IGFBP7, a novel immunohistochemical marker in differentiating dermatofibroma from dermatofibrosarcoma protuberans

BACKGROUND

Loss of insulin-like growth factor-binding protein 7 (IGFBP7) has been found to be a critical step in the development of melanoma and colon cancer. To our knowledge, immunostaining of IGFBP7 in various dermatofibrosarcoma protuberans (DFSP) and dermatofibroma (DF) has not been studied before.

OBJECTIVES

To assess the immunostaining of IGFBP7 in DFSPs and DFs and to ascertain whether IGFBP7 is superior to antibodies traditionally used in differentiating DFs from DFSPs.

METHODS

Immunohistochemical staining was performed on 28 cases of DFSP and 30 cases of DF, using antibodies to IGFBP7, CD34, factor XIIIa (FXIIIa), CD10 and stromelysin-3 (ST-3).

RESULTS

Six of 28 (21.4%) DFSP samples were positive for IGFBP7, whereas 28 of 30 (93.3%) DF samples were positive. CD34 was positive in 26 of 28 (92.9%) cases of DFSP and 4 of 30 (13.3%) cases of DF. FXIIIa staining was positive in 4 of 28 (14.3%) cases of DFSP and 28 of 30 (93.3%) cases of DF. CD10 staining was positive in 12 of 28 (42.9%) cases of DFSP and ST-3 staining was positive in 7 of 28 (25.0%) cases of DFSP. The preferential IGFP7 staining of DFSPs in comparison with DFs was statistically significant (P < 0.01).

CONCLUSIONS

We confirmed that IGFBP7 is a negative immunohistochemical marker for DFSPs and the combination with CD34, FXIIIa and ST-3 immunostaining could make the distinction more reliable.

Activation of the activin A-ALK-Smad pathway in systemic sclerosis

Systemic sclerosis (SSc) is a chronic disease of unknown etiology that is characterized by multiple tissue fibrosis. Transforming Growth Factor-beta (TGF-β) is thought to be the most important mediator that induces fibrosis. However, the molecular mechanisms by which fibrosis is induced have not been fully elucidated. In this study, the role of activin, a member of the TGF-β superfamily, was investigated in the pathogenesis of fibrosis in SSc. Serum activin A levels in patients with SSc were measured by ELISA, and the expression of the activin receptor type IB (ACVRIB/ALK4) and the activity of the signaling pathway via ACVRIB/ALK4 were investigated using western blotting. To evaluate a potential therapeutic strategy for SSc, we also attenuated the ACVRIB/ALK4 pathway using an inhibitor. Serum activin A levels were significantly higher in SSc patients than in normal controls. Activin A and ACVRIB/ALK4 expression were also higher in cultured SSc fibroblasts. Activin A stimulation induced phosphorylation of Smad2/3 and CTGF expression in SSc fibroblasts. Procollagen production and Col1α mRNA also increased upon stimulation by activin A. The basal level of Smad2/3 phosphorylation was higher in cultured SSc fibroblasts than in control cells, and treatment with the ALK4/5 inhibitor SB431542 prevented phosphorylation of Smad2/3 and CTGF expression. Furthermore, production of collagen was also induced by activin A. Activin A-ACVRIB/ALK4-Smad-dependent collagen production was augmented in SSc fibroblasts, suggesting the involvement of this signaling mechanism in SSc. Inhibition of the activin A-ACVRIB/ALK4-Smad pathway would be a new approach for the treatment of SSc.

Differences in the expression of glycosaminoglycans in human fibroblasts derived from gingival overgrowths is related to TGF-beta up-regulation

Glycosaminoglycans (GAGs) play important roles in cell behavior and have the ability to bind and modulate cytokines. Using primary cultured fibroblasts from hereditary gingival fibromatosis (HGF), normal gingiva (NG), and NG treated with cyclosporin-A (NGc) we show changes in the expression and structural characteristics of GAGs as well as in the expression of enzymes involved in their biosynthesis and degradation. In addition, we show the over-expression of TGF-beta1 and TGF-beta type II receptor in HGF and NGc. There is an increase in the GAGs retained in the cellular fraction, and the fine structure of galactosaminoglycans show a decrease in alpha-l-iduronic acid content in HGF and NGc. Elevated extracellular levels of low molecular weight hyaluronan (HA) are found in HGF due to increase in the expression of HA synthase 3 and hyaluronidases 1 and 2. The results bring new insights to the accumulation of extracellular matrix related to TGF-beta over-expression.

Dermatofibroma: a possible model of local fibrosis with epithelial/mesenchymal cell interaction

Dermatofibromas are benign dermal nodules usually seen on the extremities; however, whether a dermatofibroma is a reactive fibrous hyperplasia or a true neoplasm is still unclear. Fibrous type dermatofibromas might be regarded as the symptom of local fibrotic processes and thus present a possible model of local fibrosis. Interaction between proliferated dermatofibroma fibroblasts and overlying elongated epidermis suggests a relationship between keratinocytes and mesenchymal cells. We herein describe current insights into the pathogenesis of dermatofibromas and explore the possible involvement of immunocytes around fibroblasts and effector cells which play an important role in the development of dermatofibromas.

Stromelysin-3 expression in the differential diagnosis of dermatofibroma and dermatofibrosarcoma protuberans: comparison with factor XIIIa and CD34

BACKGROUND

The distinction between dermatofibroma (DF) and dermatofibrosarcoma protuberans (DFSP) is a well-known challenge for dermatopathologists. Immunohistochemical stains have been used to augment routine histological examination to aid in differentiating DF from DFSP. Stromelysin-3 (ST3) is a member of the matrix metalloproteinase (MMP) family, MMP-11, which is expressed in the skin during wound healing and in the stroma of basal cell carcinoma. Recent studies demonstrated that DFs expressed ST3, whereas DFSPs were only rarely ST3 positive.

OBJECTIVES

To assess the expression of ST3 in DF and DFSP and to ascertain whether ST3 is superior to factor XIIIa or CD34 in differentiating DF from DFSP, by comparison with factor XIIIa and CD34 expression.

METHODS

Immunohistochemical staining was performed on 23 cases of DF and 17 cases of DFSP, using antibodies to ST3, factor XIIIa and CD34.

RESULTS

ST3 was expressed in all cases of DF (23 of 23) but only one case showed weakly positive staining in DFSP (one of 17). The mean +/- SD ST3 immunohistochemistry (IHC) score in DF was 4.52 +/- 0.67. The sensitivity of ST3 was 100% and the specificity was 94%. Factor XIIIa was expressed in all cases of DF (23 of 23) and in five of the 17 DFSPs. The mean +/- SD factor XIIIa IHC score in the DFs was 4.43 +/- 0.73. The sensitivity of factor XIIIa was 100% and the specificity was 71%. CD34 was expressed in four of the 23 DFs and 16 of the 17 DFSPs. The mean +/- SD CD34 IHC score in the DFSPs was 4.41 +/- 1.37. The sensitivity of CD34 was 94% and the specificity was 83%.

CONCLUSIONS

Immunohistochemical staining with a commercial anti-ST3 antibody can be successfully carried out in routine dermatopathology. We confirmed that ST3 is a positive marker for DF and that ST3 staining might be more reliable than factor XIIIa staining in differential diagnosis of DF and DFSP. As the present study showed that ST3 was not absolutely negative in all cases of DFSP, the combination with CD34 immunostaining could make the distinction more reliable.