The expression of syndecan-1 is preferentially reduced compared with that of E-cadherin in acantholytic squamous cell carcinoma

Matrix Effectors in the Pathogenesis of Keratinocyte-Derived Carcinomas

Basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), referred to as keratinocyte carcinomas, are skin cancer with the highest incidence. BCCs, rarely metastasize; whereas, though generally not characterized by high lethality, approximately 2–4% of primary cSCCs metastasize with patients exhibiting poor prognosis. The extracellular matrix (ECM) serves as a scaffold that provides structural and biological support to cells in all human tissues. The main components of the ECM, including fibrillar proteins, proteoglycans (PGs), glycosaminoglycans (GAGs), and adhesion proteins such as fibronectin, are secreted by the cells in a tissue-specific manner, critical for the proper function of each organ. The skin compartmentalization to the epidermis and dermis compartments is based on a basement membrane (BM), a highly specialized network of ECM proteins that separate and unify the two compartments. The stiffness and assembly of BM and tensile forces affect tumor progenitors' invasion at the stratified epithelium's stromal border. Likewise, the mechanical properties of the stroma, e.g., stiffness, are directly correlated to the pathogenesis of the keratinocyte carcinomas. Since the ECM is a pool for various growth factors, cytokines, and chemokines, its' intense remodeling in the aberrant cancer tissue milieu affects biological functions, such as angiogenesis, adhesion, proliferation, or cell motility by regulating specific signaling pathways. This review discusses the structural and functional modulations of the keratinocyte carcinoma microenvironment. Furthermore, we debate how ECM remodeling affects the pathogenesis of these skin cancers.

Acantholytic Squamous Cell Carcinoma Arising From Lichen Sclerosus: A Rare Case Affecting Vulvar Skin

We present the case of an 82-year-old female with acantholytic squamous cell carcinoma affecting vulvar skin. The patient had a history of perineal lichen sclerosus for 5 years before presentation. She was referred to a dermatologist for intractable severe pain associated with the lesions. Biopsies showed an infiltrative squamous cell carcinoma with histology consistent with the acantholytic subtype. Acantholytic squamous cell carcinoma is a rare histologic variant characterized by dyscohesive keratinocytes with pseudoglandular formation and dyskeratosis. It is associated with sun-damaged skin and most commonly occurs in the head and neck of elderly men. Few cases have been reported at nondermal sites and non-sun-exposed dermis. The patient underwent a radical vulvectomy and bilateral inguinal node dissection. The 1.6 cm tumor was diffusely acantholytic and pseudoglands were present. The tumor cells were diffusely positive for p63 immunohistochemical stain. As expected at this site, there was no solar elastosis identified histologically. However, vulvar intraepithelial neoplasia and chronic lichen sclerosus were apparent. This case represents a rare histologic subtype of squamous cell carcinoma in an unusual site associated with lichen sclerosus instead of solar elastosis.

A rare acantholytic variant of squamous cell carcinoma of the maxilla: A case report and literature review

RATIONALE

Acantholytic squamous cell carcinoma (ASCC) is an uncommon histopathologic variant of squamous cell carcinoma (SCC), which is the most common malignancy of the oral cavity. Though ASCC showed poor prognosis, the exact diagnosis is challenging.

PATIENTS CONCERNS

A 59-year-old female patient with 1-month long symptoms of pain and burning sensation in the right maxilla.

DIAGNOSES

Incisional biopsy in the maxilla established the pathologic diagnosis of SCC.

INTERVENTION

The patient underwent mass resection with near total maxillectomy.

OUTCOMES

The final diagnosis through the microscopic examination was ASCC. Palliative chemotherapy was done to relive the symptoms after the recurrence, however, the patient died of the disease at 8 months after her initial presentation.

LESSONS

Special attention should be paid to this variant of SCC because most patients with ASCC have a very poor prognosis.

Acantholytic Squamous Cell Carcinoma and Salivary Duct Carcinoma Ex-pleomorphic Adenoma of the Submandibular Gland: A Report of Two Extremely Rare Cases with an Immunohistochemical Analysis

Carcinoma ex pleomorphic adenoma (CXPA) is a malignant tumor of the salivary gland that arises from pleomorphic adenoma (PA). Squamous cell carcinoma (SCC) is extremely rare in the salivary glands. We report two cases of acantholytic SCC (ASCC) ex PA. Case 1 involved a 72-year-old female, and case 2 involved a 67-year-old male. Histologically, both cases involved PA, and salivary duct carcinoma (SDC) components, which were positive for androgen receptor (AR) and gross cystic disease fluid protein (GCDFP)-15 but negative for HER2, were seen in the intracapsular regions. The invasive components consisted of ASCC, which were positive for cytokeratin 5/6 and p63 but negative for AR and GCDFP-15. The SDC and ASCC components were positive for the epidermal growth factor receptor. In both cases, the cytoplasmic localization or decreased expression of E-cadherin was observed in the ASCC. In the early phase, CXPA might emerge as SDC, and it might change into SCC as it invades beyond the capsule due to changes in microenvironment. Also, the aberrant expression of E-cadherin is related to acantholysis in SCC.

Role of the extracellular matrix in cancer-associated epithelial to mesenchymal transition phenomenon

The epithelial to mesenchymal transition (EMT) program is a crucial component in the processes of morphogenesis and embryonic development. The transition of epithelial to mesenchymal phenotype is associated with numerous structural and functional changes, including loss of cell polarity and tight cell-cell junctions, the acquisition of invasive abilities, and the expression of mesenchymal proteins. The switch between the two phenotypes is involved in human pathology and is crucial for cancer progression. Extracellular matrices (ECMs) are multi-component networks that surround cells in tissues. These networks are obligatory for cell survival, growth, and differentiation as well as tissue organization. Indeed, the ECM suprastructure, in addition to its supportive role, can process and deliver a plethora of signals to cells, which ultimately regulate their behavior. Importantly, the ECM derived signals are critically involved in the process of EMT during tumorigenesis. This review discusses the multilayer interaction between the ECM and the EMT process, focusing on contributions of discrete mediators, a strategy that may identify novel potential target molecules. Developmental Dynamics 247:368-381, 2018. © 2017 Wiley Periodicals, Inc.

Cutaneous Squamous Cell Carcinoma: Review of the Eighth Edition of the American Joint Committee on Cancer Staging Guidelines, Prognostic Factors, and Histopathologic Variants

Cutaneous squamous cell carcinoma is the second most common form of nonmelanoma skin cancer after basal cell carcinoma and accounts for the majority of nonmelanoma skin cancer-related deaths. In 2017, the American Joint Committee on Cancer revised the staging guidelines of cutaneous squamous cell carcinoma to reflect recent evidence concerning high-risk clinicopathologic features. This update reviews the literature on prognostic features and staging, including the eighth edition of the American Joint Committee on Cancer Staging Manual. A wide range of histopathologic variants of cutaneous squamous cell carcinoma exists, several of which are associated with aggressive behavior. A review of cutaneous squamous cell carcinoma variants, emphasizing diagnostic pitfalls, immuhistochemical findings and prognostic significance, is included. Of note, the eighth edition of the American Joint Committee on Cancer Staging Manual refers to squamous cell carcinoma of the head and neck only.

Molecular and clinical profiles of syndecan-1 in solid and hematological cancer for prognosis and precision medicine

Syndecan-1 (SDC1, CD138) is a key cell surface adhesion molecule essential for maintaining cell morphology and interaction with the surrounding microenvironment. Deregulation of SDC1 contributes to cancer progression by promoting cell proliferation, metastasis, invasion and angiogenesis, and is associated with relapse through chemoresistance. SDC1 expression level is also associated with responses to chemotherapy and with prognosis in multiple solid and hematological cancers, including multiple myeloma and Hodgkin lymphoma. At the tissue level, the expression levels of SDC1 and the released extracellular domain of SDC1 correlate with tumor malignancy, phenotype, and metastatic potential for both solid and hematological tumors in a tissue-specific manner. The SDC1 expression profile varies among cancer types, but the differential expression signatures between normal and cancer cells in epithelial and stromal compartments are directly associated with aggressiveness of tumors and patient's clinical outcome and survival. Therefore, relevant biomarkers of SDC signaling may be useful for selecting patients that would most likely respond to a particular therapy at the time of diagnosis or perhaps for predicting relapse. In addition, the reciprocal expression signature of SDC between tumor epithelial and stromal compartments may have synergistic value for patient selection and the prediction of clinical outcome.

Syndecan-1 in Cancer: Implications for Cell Signaling, Differentiation, and Prognostication

Syndecan-1, a cell surface heparan sulfate proteoglycan, is critically involved in the differentiation and prognosis of various tumors. In this review, we highlight the synthesis, cellular interactions, and the signalling pathways regulated by syndecan-1. The basal syndecan-1 level is also crucial for understanding the sequential changes involving malignant transformation, tumor progression, and advanced or disseminated cancer stages. Moreover, we focus on the cellular localization of this proteoglycan as cell membrane anchored and/or shed, soluble syndecan-1 with stromal or nuclear accumulation and how this may carry different, highly tissue specific prognostic information for individual tumor types.

Desmosomal defects in acantholytic squamous cell carcinomas

BACKGROUND

Acantholytic squamous cell carcinoma (Acantholytic SCC) are epithelial tumors characterized by a loss of cell adhesion between neoplastic keratinocytes. The mechanism underlying loss of cell-cell adhesion in these tumors is not understood.

METHODS

A retrospective analysis of acantholytic SCC (n = 17) and conventional SCC (n = 16, controls not showing acantholysis) was conducted using a set of desmosomal and adherens junction protein antibodies. Immunofluorescence microscopy was used to identify tumors with loss of adhesion protein expression.

RESULTS

The vast majority of acantholytic SCC (89%) showed focal loss of at least one desmosomal cell adhesion protein. Most interestingly, 65% of these tumors lost expression of two or more desmosomal proteins.

CONCLUSIONS

Loss of cell adhesion in acantholytic SCC is most likely linked to the focal loss of desmosomal protein expression, thus providing potential mechanistic insight into the patho-mechanism underlying this malignancy.

Epithelial to mesenchymal transition markers are associated with an increased metastatic risk in primary cutaneous squamous cell carcinomas but are attenuated in lymph node metastases

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is the second most common malignancy in humans and approximately 5% metastasize, usually to regional lymph nodes. Epithelial to mesenchymal transition (EMT) is a process involving loss of intercellular adhesion, acquisition of a mesenchymal phenotype and enhanced migratory potential; epithelial markers, such as E-cadherin, are down-regulated and mesenchymal proteins (Vimentin), increased.

OBJECTIVE

To investigate the expression of EMT markers in metastatic SCC (MSCC) and their corresponding metastases, and to correlate them with clinico-pathological factors associated with an increased risk of metastasis.

METHODS

We performed a retrospective study that included 146 cSCC samples (51 primary non-metastatic, 56 primary metastatic, 39 lymphatic metastases). Immunohistochemistry for E-cadherin, Vimentin, Snail, beta-catenin, Twist, Zeb1 and Podoplanin was performed.

RESULTS

Loss of membranous E-cadherin was observed in 77% cSCCs, with no differences between MSCC and non-MSCC. Among the transcriptional factors controlling EMT, no significant Snail1 expression was detected. Twist, Zeb1, Vimentin, beta-catenin and Podoplanin were significantly overexpressed in MSCCs. Twist ectopic expression in SCC13 cells induced Zeb1, Vimentin and Podoplanin expression and E-cadherin delocalization. These changes resulted in a scattered migration pattern in vitro. Expression of EMT markers was decreased in the metastases when compared with the corresponding primary tumors.

CONCLUSION

These results suggest that a partial EMT, characterized by the expression of Twist but without a total E-cadherin depletion, is involved in the acquisition of invasive traits by cSCC, but the process is downregulated in lymph node metastases.

Decreased expression of intercellular adhesion molecules in acantholytic squamous cell carcinoma compared with invasive well-differentiated squamous cell carcinoma of the skin

Intercellular adhesion proteins are poorly characterized in acantholytic squamous cell carcinoma (ASCC), a more aggressive tumor than nonacantholytic invasive well-differentiated squamous cell carcinoma (SCC) of the skin. In this study we compared expression of Dsg3, E-cadherin, and syndecan-1 in ASCC and SCC. Immunohistochemical detection of Dsg3, E-cadherin, and syndecan-1 in 22 ASCCs and 22 SCCs was graded on a semiquantitative scale for intensity of staining (SI) and degree of circumferential staining (CS) about the cell membrane. Results were assessed by means of conditional logistic regression and χ(2) analysis. Dsg3 and E-cadherin expression (SI, CS) was significantly decreased (P < .05) in ASCC compared with SCC, whereas staining for syndecan-1 was similar in the 2 tumor types. Differences in expression of adhesion markers between ASCC and SCC may contribute to the development of acantholysis in ASCC and its more aggressive biologic behavior.

Pseudoangiosarcomatous squamous cell carcinoma of the lung

Pulmonary pseudoangiosarcomatous squamous cell carcinoma (PSCC) is a rare aggressive variant of squamous cell carcinoma. Histopathologically, PSCC is characterized by interanastomosing cords and channels, lined by atypical cells, with spaces containing erythrocytes or floating tumour cells. PSCC mimics angiosarcoma, so careful attention should be paid to immunohistochemical differences. Two PSCC cases are described here: in a 79-year-old male, bronchoscopy revealed mucosal swelling and hypertrophy and an adrenal mass was found 1 month later; in a 76-year-old male, computed tomography revealed rib destruction due to a non-calcified soft-tissue tumour and, although the tumour resembled an angiosarcoma, endothelial markers were negative and cytokeratin and p63 markers were positive. Immunohistochemical analyses may be helpful in establishing an accurate diagnosis. PSCC had a progressive course in both patients, who died ≤ 3 months postdiagnosis.

Antithetic roles of proteoglycans in cancer

Proteoglycans (PGs), a family of complex post-translationally sculptured macromolecules, are fundamental regulators of most normal and aberrant cellular functions. The unparalleled structural-functional diversity of PGs endows them with the ability to serve as critical mediators of the tumor cells' interaction with the host microenvironment, while directly contributing to the organization and dynamic remodeling of this milieu. Despite their indisputable importance during embryonic development and in the adult organism, and their frequent dysregulation in tumor lesions, their precise involvement in tumorigenesis awaits a more decisive demonstration. Particularly challenging is to ascertain to what extent selected PGs may catalyze tumor progression and to what extent they may inhibit it, implying antithetic functions of individual PGs. Integrated efforts are needed to consolidate the routine use of PGs in the clinical monitoring of cancer patients and to broaden the exploitation of these macromolecules as therapeutic targets. Several PGs have the required attributes to be contemplated as effective antigens for immunotherapeutic approaches, while the tangible results obtained in recent clinical trials targeting the NG2/CSPG4 transmembrane PG urge further development of PG-based cancer treatment modalities.

Primary acantholytic squamous cell carcinoma of the cecum: a case report

Background

Acantholytic squamous cell carcinoma (ASCC) is an uncommon histopathologic variant of SCC, characterized by marked acantholysis, wherein the tumor cells demonstrate defective cohesion to one another in the cancer nest leading to a pseudoglandular or pseudovascular appearance. The most common site of ASCC is the sun-exposed areas of the skin. Sporadic cases of ASCC have also been reported in various mucosal membranes and organs but to our knowledge this is the first case of primary ASCC of the large bowel.

Case presentation

A 59-year-old woman underwent right hemicolectomy due to large tumor in cecum and initial part of the ascending colon. Microscopically, the tumor consisted of nests of focally keratinizing large, atypical, squamous epithelial cells. Approximately 70% of the tumor showed acantholytic changes and acantholysis was equally distributed through the entire tumor. Immunohistochemically tumor cells were diffusely positive for cytokeratin (CK) AE1/AE3 and focally positive for epithelial membrane antigen and syndecan 1. All other tested antibodies (CK7, CK 20, CK MNF116, E-cadherin, beta-catenin, p63, p16, CD31, CD34, CEA, estrogen, progesterone) showed negative reaction. Periodic acid Schiff and alcian blue staining showed no intracellular or extracellular mucinous material in the tumor. The diagnosis of acantholytic squamous cell carcinoma of the cecum was suspected and additional examination was recommended to exclude possibility of metastatic carcinoma. Extensive clinical examination which also included whole-body PET/CT scan showed no additional tumors. After the exclusion of possible metastatic disease the diagnosis of primary acantholytic squamous cell carcinoma of the cecum was confirmed. Six months after surgery the metastasis in small intestine and recurrence in the abdominal cavity at the site of surgery appeared and had the same morphological characteristic as the primary tumor in the cecum.

Conclusion

We report a unique case of ASCC arising in cecum and on this way expands the range of tumors originating in colon. Reports of more cases of colonic ASCC would possibly help to elucidate origin, clinical behavior and therapy of these tumors.

Acantholytic squamous cell carcinoma of the gingiva: report of a case and review of the literature

Adenoid squamous cell carcinoma differs from common squamous cell carcinoma in histologic features and its aggressive nature. Microscopically, the tumor shows cystic degeneration of the neoplastic epithelium, producing a prominent alveolar pattern and pseudoglandular structures with acantholytic cells. It occurs most commonly on the lips, rarely intraorally, and it is associated with a poor prognosis. This case concerns a 72-year-old woman who presented with the chief complaint of burning tongue and soreness of the lips. Clinical examination revealed an ulcerated and elevated mass on the edentulous left maxillary ridge, beneath the base of a partial denture. An incisional biopsy rendered the diagnosis of adenoid squamous cell carcinoma. The patient was referred to a specialized maxillofacial surgery center for diagnostic work-up and treatment. She underwent partial maxillectomy and radiotherapy, and 17 months after treatment, she died of uncontrollable recurrence.

Angiosarcoma-like metastatic carcinoma of the liver

Two cases of metastatic carcinoma strikingly simulating angiosarcoma in the liver are described. The first case was a 53-year-old female with cystic liver tumors which were found 22 months after surgery for ureteral cancer. The second case was an 81-year-old female with multiple tumors in the liver and the pancreas, and a post-mortem examination was carried out. She had undergone surgery for skin cancer three years before. Both cases had an angiosarcoma-like appearance macroscopically and microscopically. Immunohistochemically, the tumor cells of both cases were negative for CD31, CD34, and Factor VIII-related antigen and positive for several types of cytokeratin, suggesting that they were not angiosarcomas but carcinomas. Angiosarcoma is the most common sarcoma arising in the liver. Thus, metastatic carcinoma, which resembles angiosarcoma, might be mistaken for angiosarcoma.

The expression of syndecan-1 in psoriatic epidermis

Psoriasis is a chronic inflammatory skin disease characterized by exaggerated keratinocyte proliferation. Current opinion indicates that psoriasis is driven by T cell-mediated immune responses targeting keratinocytes. However, psoriasis cannot be explained solely on the basis of T-cell activation, and it is likely that an intrinsic alteration in epidermal keratinocytes plays a very important role in disease expression. Syndecans comprise a major family of cell surface heparan sulfate proteoglycans. Several studies indicate their role in adhesion, cell-extracellular matrix interactions, migration, keratinocyte proliferation and differentiation, inflammation, and wound healing. To determine the expression of syndecan-1 in psoriasis, skin samples from 29 patients with fully developed psoriasis and skin samples from 14 healthy volunteer persons with no personal or family history of psoriasis were immunohistochemically examined using monoclonal antibody against syndecan-1. The expression of syndecan-1 was analyzed in whole mount section of psoriatic and non-psoriatic skin biopsies under high magnification (400×). In addition, the intensity and topography of reaction in the cell, as well as localization of positive cells in the epidermis were evaluated. Strong syndecan-1 reactivity in epidermal cells in all non-psoriatic and psoriatic samples was observed. Statistical analysis showed no significant differences between two analyzed groups (P > 0.05). In normal skin syndecan-1 was expressed in full thickness of the epidermis. The strongest reaction was observed in membranes and intercellular junctions of spinous and granular layer while basal cells showed weaker expression that was confined to cytoplasm. In psoriatic skin syndecan-1 was expressed in the membrane and intercellular junction of cells located in thickened and elongated rete ridges of the epidermis. The strongest reaction was in basal and suprabasal layers and expression diminished through spinous layer. Cells in spinous layer lose syndecan-1 expression, which is opposite pattern to normal skin. Our results suggest that aberrant skin expression of syndecan-1 may be involved in the development of psoriasis.

Transformation-specific matrix metalloproteinases (MMP)-7 and MMP-13 are expressed by tumour cells in epidermolysis bullosa-associated squamous cell carcinomas

BACKGROUND

Patients with recessive dystrophic epidermolysis bullosa (RDEB) have an increased risk of developing rapidly progressive and metastatic cutaneous squamous cell carcinomas (SCC). It is unclear why these SCC behave more aggressively than sporadic SCC. Matrix metalloproteinases (MMP) are a family of endopeptidases that contribute to growth, invasion and metastasis of SCC. The role of MMP in RDEB-associated SCC is not known.

OBJECTIVES

To investigate the expression of MMP-7, MMP-13 and MMP-9 in RDEB-associated SCC in comparison with sporadic SCC and Bowen's disease.

METHODS

Immunohistochemical analysis of 25 RDEB-associated SCC, 61 sporadic SCC and 28 sporadic lesions of Bowen's disease was carried out using monoclonal antibodies for MMP-7, MMP-9, MMP-13 and E-cadherin and syndecan-1.

RESULTS

MMP-7 was detected in all RDEB-associated SCC, in tumour cells within the invasive edge, where E-cadherin and syndecan-1 were markedly diminished or absent. MMP-7 expression was also observed in 98% of sporadic SCC and in 68% of Bowen's diseases. MMP-7 staining was significantly stronger in RDEB-associated SCC than in sporadic SCC, and was most abundant in poorly differentiated tumours. MMP-13 was detected in tumour cells in 96% of RDEB-associated SCC and in all sporadic cutaneous SCC. MMP-9 was detected in the inflammatory cells in all SCC examined.

CONCLUSIONS

These results identify MMP-7 and MMP-13 as tumour cell-specific markers for SCC progression and as potential therapeutic targets in RDEB-associated SCC. The pattern of immunolabelling suggests that MMP-7 may shed E-cadherin and syndecan-1 from the SCC cell surface.

Reduced migration, altered matrix and enhanced TGFbeta1 signaling are signatures of mouse keratinocytes lacking Sdc1

We have reported previously that syndecan-1 (Sdc1)-null mice show delayed re-epithelialization after skin and corneal wounding. Here, we show that primary keratinocytes obtained from Sdc1-null mice and grown for 3-5 days in culture are more proliferative, more adherent and migrate more slowly than wt keratinocytes. However, the migration rates of Sdc1-null keratinocytes can be restored to wild-type levels by replating Sdc1-null keratinocytes onto tissue culture plates coated with fibronectin and collagen I, laminin (LN)-332 or onto the matrices produced by wild-type cells. Migration rates can also be restored by treating Sdc1-null keratinocytes with antibodies that block alpha6 or alphav integrin function, or with TGFbeta1. Antagonizing either beta1 integrin function using a function-blocking antibody or TGFbeta1 using a neutralizing antibody reduced wild-type keratinocyte migration more than Sdc1-null keratinocyte migration. Cultures of Sdc1-null keratinocytes accumulated less collagen than wild-type cultures but their matrices contained the same amount of LN-332. The Sdc1-null keratinocytes expressed similar total amounts of eight different integrin subunits but showed increased surface expression of alphavbeta6, alphavbeta8, and alpha6beta4 integrins compared with wild-type keratinocytes. Whereas wild-type keratinocytes increased their surface expression of alpha2beta1, alphavbeta6, alphavbeta8, and alpha6beta4 after treatment with TGFbeta1, Sdc1-null keratinocytes did not. Additional data from a dual-reporter assay and quantification of phosphorylated Smad2 show that TGFbeta1 signaling is constitutively elevated in Sdc1-null keratinocytes. Thus, our results identify TGFbeta1 signaling and Sdc1 expression as important factors regulating integrin surface expression, activity and migration in keratinocyte and provide new insight into the functions regulated by Sdc1.

A Clinicopathological and Immunohistochemical Comparison of Squamous Cell Carcinoma Arising in Scars Versus Nonscar SCC in Japanese Patients

Squamous cell carcinoma (SCC) of the skin shows an indolent prognosis in general. However, the prognosis of SCC arising in a scar (scar carcinoma) is considered to be worse than that of SCC without any clinical history of injury (nonscar SCC). The aim of this study was to compare several indices, p53, Ki-67, E-cadherin, and beta-catenin, which are related to tumor behavior, between scar carcinoma and nonscar SCC clinicopathologically and immunohistochemically. The materials were from 10 cases of scar carcinoma and 10 cases of nonscar SCC. Clinicopathologically, the mean ages at diagnosis of scar carcinoma and nonscar SCC were 59.2 and 71.2, respectively. The most frequent anatomic site of scar carcinoma was the limbs. The most common cause of scars in our study was burns. The mean duration from the initial injury to the diagnosis of carcinoma was 30.5 years. Immunohistochemically, the mean labeling index (calculated as the percentage of positive cells) of p53 was 16.5 and 58.6 in scar carcinoma and nonscar SCC, respectively (P < 0.01, Welch test). The LI of Ki-67 was 19.1 in scar carcinoma and 52.1 in nonscar SCC (P < 0.01, Welch test). The rates of positivity of the other proteins, such as E-cadherin and beta-catenin, were similar between scar carcinoma and nonscar SCC. In this study, the follow-up time was short and the number of patients was small, and for these reasons it might not have been possible to obtain evidence that scar carcinoma is aggressive.

Pseudovascular adenoid squamous-cell carcinoma of the oral cavity--a report of two cases

Informed consent was obtained for the publication of the patients' details in this report. Two cases of pseudovascular adenoid squamous-cell carcinoma (SCC) in the oral cavity are described, which were characterised by acantholysis of the tumour cells, with formation of anastomosing spaces and channels mimicking an angiosarcoma. Both tumours contained foci of SCC suggesting the correct diagnosis: in one patient conventional SCC, and in the other, a spindle-cell carcinoma. The pathogenesis of pseudovascular adenoid SCC is unknown. Our cases were characterised by loss of immunohistochemical expression of E-cadherin, one of the major adhesion molecules of epithelial cells. Pseudovascular adenoid SCC is suggested to be pathogenetically related to the loss of E-cadherin expression, leading to the loss of tumour cell-cell adhesion.

Reduced syndecan-1 expression is correlated with the histological grade of malignancy at the deep invasive front in oral squamous cell carcinoma

BACKGROUND

Although many histopathological characteristics of oral squamous cell carcinoma (O-SCC) have been identified as prognostic factors, no factor is completely accurate and unequivocal. This study evaluated the association between the loss of syndecan-1 expression and the histological grade of malignancy at the deep invasive front in O-SCC.

METHODS

The expression of syndecan-1 at the invasive tumor front of O-SCC was examined immunohistochemically using archived tissue from 72 cases. The mean age of the patients was 62.5 years (range: 23-90 years) and the male-female ratio was 1.3:1 (41 men, 31 women). There were 26, 24, 11, and 11 cases classified as stages I-IV respectively. The correlation between the intensity of syndecan-1 immunostaining and the clinicopathological factors, especially the histological grade of malignancy at the deep invasive front (invasive front grade) was analyzed.

RESULTS

Of the 72 cases, seven (9.7%), 29 (40.3%), 36 (50.0%) showed strong, intermediate, and weak or negative syndecan-1 staining respectively. There were significant differences between syndecan-1 expression and prognosis, differentiation, and pattern of invasion at the deep invasive front. Moreover, the invasive front grade scores, based on the intensity of syndecan-1 staining, were 5.6 +/- 1.0, 8.0 +/- 2.1, and 10.2 +/- 2.3 points with strong, intermediate, and weak or negative intensity respectively; and the difference was significant (P < 0.0001). Patients with intermediate or strong intensity for syndecan-1 had significantly better prognoses than did those with negative or weak intensity (P = 0.0138).

CONCLUSION

This study demonstrated that the reduced expression of syndecan-1 seems to be a useful marker of histological malignancy at the deep tumor invasive front and may be a useful prognostic factor in O-SCC.

Focal Adhesion Kinase Regulates Syndecan-2–Mediated Tumorigenic Activity of HT1080 Fibrosarcoma Cells

Expression of syndecan-2, a transmembrane heparan sulfate proteoglycan, is crucial for the tumorigenic activity in colon carcinoma cells. However, despite the high-level expression of syndecan-2 in mesenchymal cells, few studies have addressed the function of syndecan-2 in sarcoma cells. In HT1080 fibrosarcoma cells, we found that syndecan-2 regulated migration, invasion into Matrigel, and anchorage-independent growth but not cell-extracellular matrix adhesion or proliferation, suggesting that syndecan-2 plays different functional roles in fibrosarcoma and colon carcinoma cells. Consistent with the increased cell migration/invasion of syndecan-2-overexpressing HT1080 cells, syndecan-2 overexpression increased phosphorylation and interaction of focal adhesion kinase (FAK) and phosphatidylinositol 3-kinase (PI3K), membrane localization of T-lymphoma invasion and metastasis gene-1 (Tiam-1), and activation of Rac. Syndecan-2-mediated cell migration/invasion of HT1080 cells was diminished when (a) cells were cotransfected with nonphosphorylatable mutant FAK Y397F or with other FAK mutants lacking PI3K interactions, (b) cells were treated with a specific PI3K inhibitor, or (c) levels of Tiam-1 were knocked down with small interfering RNAs. Furthermore, expression of several FAK mutants inhibited syndecan-2-mediated enhancement of anchorage-independent growth in HT1080 cells. Taken together, these data suggest that syndecan-2 regulates the tumorigenic activities of HT1080 fibrosarcoma cells and that FAK is a key regulator of syndecan-2-mediated tumorigenic activities.

Syndecan-1 expression--a novel prognostic marker in pancreatic cancer

OBJECTIVE

Syndecan-1 is a transmembrane receptor that participates in cell-cell and cell-matrix interactions, cell proliferation and cell migration. Expression of syndecan-1 is downregulated in many cancers, but in pancreatic ductal adenocarcinoma it is upregulated.

METHOD

We studied the immunohistochemical expression of syndecan-1 in 144 pancreatic adenocarcinomas and evaluated the prognostic value of syndecan-1 expression. Formalin-fixed, paraffin-embedded specimens were stained with mouse monoclonal antibody B-B4 against human syndecan-1. The epithelial and stromal staining was separately evaluated and compared with patient survival, clinical stage and histological grade.

RESULT

Epithelial immunoreactivity was observed in most of the pancreatic carcinoma samples: in 70 (49%) of the samples the epithelial staining was weak, in 48 (33%) moderate, in 18 (12%) strong and in only 8 (6%) of the samples the epithelial staining was negative. Stromal staining was weak in 24 (17%), moderate in 31 (22%), strong in 11 (8%) and negative in 78 (54%) of the pancreatic carcinoma samples. Lack of stromal expression predicted a better prognosis (p = 0.002; HR 1.7) and it was independent of stage (p = 0.01; HR = 1.5) and grade (p = 0.0004; HR 2.1) in multivariate analysis. Epithelial expression predicted better prognosis for patients that underwent surgery for cure (n = 94, p = 0.03).

CONCLUSION

Stromal syndecan-1 expression is an independent prognostic marker in pancreatic cancer, whereas epithelial syndecan-1 expression predicts better prognosis only in resectable disease.

Pseudoangiosarcomatous Squamous Cell Carcinoma of Skin Arising Adjacent to Decubitus Ulcers

Pseudoangiosarcomatous, or pseudovascular, squamous cell carcinoma of skin is an unusual form of acantholytic (adenoid, pseudoglandular) squamous cell carcinoma that mimics the histolopathologic appearance of angiosarcoma. We report a case of pseudoangiosarcomatous squamous cell carcinoma arising adjacent to decubitus ulcers. The histopathologic examination of a wedge biopsy specimen revealed infiltrative cords of neoplastic cells that formed interanastomosing channels imitating angiosarcoma. Immunohistochemical staining was negative for the endothelial markers (CD31, CD34, and factor VIII-related antigen) and positive using cytokeratin antibodies (AE1/AE3 and 34 betaE12). Because of metastatic disease, palliative measures were undertaken and the patient died four months later. To our knowledge, our patient is the first with pseudoangiosarcomatous squamous cell carcinoma of skin developing within decubitus ulcer.

Immunohistochemical and cytogenetic characterization of acantholytic squamous cell carcinoma of the breast

Primary acantholytic squamous cell carcinoma (ASCC) of the breast is a rare and aggressive variant of invasive breast cancer. Here we report two new cases of ASCC and their immunohistochemical and cytogenetic characterization. One case was associated with systemic metastases and death and the other with local failure prior to loss of follow-up. Using comparative genomic hybridization (CGH), both tumors showed a high overall number of chromosomal imbalances with a similar pattern of gains and losses. Genetic aberrations common to both tumors included losses at 3p11-p25, 5q21-q31, 8p, 9, 13p13-q21, 16q12-q21, and 17p and gains at 1q31-qter, 7p, 18q12-qter, 19q, and 20. Immunohistochemically, the tumors were characterized by high proliferative activity, an uncommon cytokeratin expression profile, reduced E-cadherin staining, and overexpression of p53 and epithelial growth factor receptor (EGFR). The results of our analyses suggest that genetic alterations observed in ASCC of the breast include imbalances commonly observed in both mammary adenocarcinoma and squamous cell carcinoma of other locations. Furthermore, the overexpressed EGFR could be a possible therapeutic target for individual cases of this aggressive tumor type.

Expression of e-cadherin and beta-catenin in cutaneous squamous cell carcinoma and its precursors

The E-cadherin-beta-catenin complex regulates the architectural integrity of epithelia by mediating intercellular adhesion. Down-regulation of its expression may contribute to invasion and metastatic behavior of carcinoma cells. Several studies demonstrated an abnormal expression of E-cadherin, beta-catenin, or both in various carcinomas, including non-melanoma skin cancer. The aim of the present study was to investigate the involvement of E-cadherin-catenin adhesion system in the progression of human cutaneous squamous cell carcinoma (SCC). For that purpose, sections from normal skin, skin showing solar elastosis (SE), solar keratosis (SK), and SCC were stained with monoclonal antibodies against E-cadherin and beta-catenin. Evaluation of the staining results was performed using a semi-quantitative method in which pattern and intensity of staining, percentage of positive cells, and cytoplasmic staining were evaluated. Normal skin and skin showing mild and moderate solar elastosis strongly expressed membranous E-cadherin and beta-catenin. E-cadherin expression was progressively reduced in the epidermis of skin with severe solar elastosis through solar keratosis to SCC. The same phenomenon was observed for beta-catenin starting from solar keratosis. In some cases of SCC, additional cytoplasmic staining was observed. We found no correlation between E-cadherin and beta-catenin expression and tumor differentiation or between SCC from sun-exposed and sun-protected skin. Statistical analysis revealed correlation between expression of both E-cadherin and beta-catenin and the morphology of the lesion. These results support a gradual evolution from severely sun-damaged skin to SCC, not only on a morphologic level, but also at the molecular level.

Dermatofibroma: Upregulation of Syndecan-1 Expression in Mesenchymal Tissue

Cell surface proteoglycans play a prominent role in tissue remodeling and homeostasis. Syndecans, their most prominent members, act by binding to growth factors and interstitial matrix molecules. They, thereby, modulate the effect of the primary ligand-receptor interaction at the cell membrane by increasing the affinity of cell-ligand interactions. Additionally, they influence the strength of cell-cell and cell-matrix interactions. Syndecan-1 is the prototypical member of this family of proteins. Under physiological conditions, its expression is restricted to the epidermis, the outer root sheath of the anagen hair follicle, and the sweat gland epithelium. The dermal compartment-with the exception of the follicular papilla of the anagen hair follicle-physiologically does not express syndecan-1. Dermatofibromas are mesenchymal lesions, which often exhibit hyperplastic changes in the overlying epidermis. In analogy to the hair follicle, they, thereby, can be used as a model for studying epithelial-mesenchymal interactions. In the current study, we examined dermatofibromas immunohistochemically for syndecan-1 expression. We report immunoreactivity for syndecan-1 in dermatofibromas, which correlates mainly with the deposition of intercellular matrix material. Syndecan-1 is also noted in the stroma surrounding areas of basaloid hyperplasia overlying dermatofibromas and may be important in the pathogenesis of this inductive phenomenon. In analogy to the follicular papilla of the anagen hair follicle, the staining pattern for syndecan-1 in dermatofibromas indicates that this cell surface protein is produced by stromal cells and most likely serves an essential function in the growth of these common mesenchymal cutaneous lesions.

Syndecan-2 mediates adhesion and proliferation of colon carcinoma cells

Syndecan-2 is a transmembrane heparan sulfate proteoglycan whose function at the cell surface is unclear. In this study, we examined the function of syndecan-2 in colon cancer cell lines. In several colon cancer cell lines, syndecan-2 was highly expressed compared with normal cell lines. In contrast, syndecan-1 and -4 were decreased. Cell biological studies using the extracellular domain of recombinant syndecan-2 (2E) or spreading assay with syndecan-2 antibody-coated plates showed that syndecan-2 mediated adhesion and cytoskeletal organization of colon cancer cells. This interaction was critical for the proliferation of colon carcinoma cells. Blocking with 2E or antisense syndecan-2 cDNA induced G(0)/G(1) cell cycle arrest with concomitantly increased expression of p21, p27, and p53. Furthermore, blocking of syndecan-2 through antisense syndecan-2 cDNA significantly reduced tumorigenic activity in colon carcinoma cells. Therefore, increased syndecan-2 expression appears to be a critical for colon carcinoma cell behavior, and syndecan-2 regulates tumorigenic activity through regulation of adhesion and proliferation in colon carcinoma cells.