Tumor cell-specific AIM2 regulates growth and invasion of cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (cSCC) is the most common metastatic skin cancer. Inflammation is a typical feature in cSCC progression. Analysis of the expression of inflammasome components in cSCC cell lines and normal human epidermal keratinocytes revealed upregulation of the expression of AIM2 mRNA and protein in cSCC cells. Elevated levels of AIM2 mRNA were noted in cSCCs in vivo compared with normal skin. Strong and moderate tumor cell specific expression of AIM2 was detected with immunohistochemistry (IHC) in sporadic human cSCCs in vivo, whereas expression of AIM2 was moderate in cSCC in situ (cSCCIS) and low or absent in actinic keratosis (AK) and normal skin. IHC of cSCCs, cSCCIS and AKs from organ transplant recipients also revealed strong and moderate tumor cell specific expression of AIM2 in cSCCs. Knockdown of AIM2 resulted in reduction in viability of cSCC cells and onset of apoptosis. RNA-seq and pathway analysis after knockdown of AIM2 in cSCC cells revealed downregulation of the biofunction category Cell cycle and upregulation of the biofunction category Cell Death and Survival. Knockdown of AIM2 also resulted in reduction in invasion of cSCC cells and downregulation in production of invasion proteinases MMP1 and MMP13. Knockdown of AIM2 resulted in suppression of growth and vascularization of cSCC xenografts in vivo. These results provide evidence for the role of AIM2 in the progression of cSCC and identify AIM2 inflammasome function as a potential therapeutic target in these invasive and metastatic tumors.

Complement Component C3 and Complement Factor B Promote Growth of Cutaneous Squamous Cell Carcinoma.

Cutaneous squamous cell carcinoma (cSCC) is one of the most common metastatic skin cancers with increasing incidence. We examined the roles of complement component C3 and complement factor B (CFB) in the growth of cSCC. Analysis of cSCC cell lines (n = 8) and normal human epidermal keratinocytes (n = 11) with real-time quantitative PCR and Western blotting revealed up-regulation of C3 and CFB expression in cSCC cells. Immunohistochemical staining revealed stronger tumor cell-specific labeling for C3 and CFB in invasive cSCCs (n = 71) and recessive dystrophic epidermolysis bullosa-associated cSCCs (n = 11) than in cSCC in situ (n = 69), actinic keratoses (n = 63), and normal skin (n = 5). Significant up-regulation of C3 and CFB mRNA expression was noted in chemically induced mouse cSCCs, compared to benign papillomas. Knockdown of C3 and CFB expression inhibited migration and proliferation of cSCC cells and resulted in potent inhibition of extracellular signal-regulated kinase 1/2 activation. Knockdown of C3 and CFB markedly inhibited growth of human cSCC xenograft tumors in vivo. These results provide evidence for the roles of C3 and CFB in the development of cSCC and identify them as biomarkers and potential therapeutic targets in this metastatic skin cancer.

Expression of claudin-11 by tumor cells in cutaneous squamous cell carcinoma is dependent on the activity of p38δ.

The incidence of cutaneous squamous cell carcinoma (cSCC) is rapidly increasing, and the prognosis of patients with metastatic disease is poor. There is an emerging need to identify molecular markers for predicting aggressive behaviour of cSCC. Here, we have examined the role of tight junction (TJ) components in the progression of cSCC. The expression pattern of mRNAs for TJ components was determined with RNA sequencing and oligonucleotide array-based expression analysis from cSCC cell lines (n=8) and normal human epidermal keratinocytes (NHEK, n=5). The expression of CLDN11 was specifically elevated in primary cSCC cell lines (n=5), but low or absent in metastatic cSCC cell lines (n=3) and NHEKs. Claudin-11 was detected in cell-cell contacts of primary cSCC cells in culture by indirect immunofluorescence analysis. Analysis of a large panel of tissue samples from sporadic UV-induced cSCC (n=65), cSCC in situ (n=56), actinic keratoses (n=31), seborrhoeic keratoses (n=7) and normal skin (n=16) by immunohistochemistry showed specific staining for claudin-11 in intercellular junctions of keratinizing tumor cells in well and moderately differentiated cSCCs, whereas no staining for claudin-11 was detected in poorly differentiated tumors. The expression of claudin-11 in cSCC cells was dependent on the activity of p38δ MAPK and knock-down of claudin-11 enhanced cSCC cell invasion. These findings provide evidence for the role of claudin-11 in regulation of cSCC invasion and suggest loss of claudin-11 expression in tumor cells as a biomarker for advanced stage of cSCC.

Long Noncoding RNA PICSAR Promotes Growth of Cutaneous Squamous Cell Carcinoma by Regulating ERK1/2 Activity.

Keratinocyte-derived cutaneous squamous cell carcinoma (cSCC) is the most common metastatic skin cancer, and its incidence is increasing globally. Long noncoding RNAs (lncRNA) are involved in various biological processes, and their role in cancer progression is emerging. Whole transcriptome analysis of cSCC cells (n = 8) and normal human epidermal keratinocytes (n = 4) revealed overexpression of long intergenic ncRNA (LINC00162) in cSCC cells. The expression of LINC00162 in cSCC cells was upregulated by inhibition of the p38α and p38δ mitogen-activated protein kinases. Analysis of tissue sections by RNA in situ hybridization showed that LINC00162 is specifically expressed by tumor cells in cSCCs but not by keratinocytes in normal skin in vivo. Knockdown of LINC00162 inhibited proliferation and migration of cSCC cells, and suppressed the growth of human cSCC xenografts in vivo. Furthermore, knockdown of LINC00162 inhibited extracellular signal-regulated kinase 1/2 activity and upregulated expression of dual specificity phosphatase 6 (DUSP6) in cSCC cells. Based on these observations, LINC00162 was named p38 inhibited cutaneous squamous cell carcinoma associated lincRNA (PICSAR). Our results provide mechanistic evidence for the role of PICSAR in promoting cSCC progression via activation of extracellular signal-regulated kinase 1/2 signaling pathway by downregulating DUSP6 expression. These results also identify PICSAR as a biomarker and putative therapeutic target in cSCC.

EphB2 Promotes Progression of Cutaneous Squamous Cell Carcinoma.

Keratinocyte-derived skin cancer, cutaneous squamous cell carcinoma (cSCC), is the most common metastatic skin cancer. We have examined the role of Eph/ephrin signaling in the progression of cSCC. Analysis of the expression of EPH and EFN families in cSCC cells and normal epidermal keratinocytes revealed overexpression of EPHB2 mRNA in cSCC cells and cSCC tumors in vivo. Tumor cell-specific overexpression of EphB2 was detected in human cSCCs and in chemically induced mouse cSCCs with immunohistochemistry, whereas the expression of EphB2 was low in premalignant lesions and normal skin. Knockdown of EphB2 expression in cSCC cells suppressed growth and vascularization of cSCC xenografts in vivo and inhibited proliferation, migration, and invasion of cSCC cells in culture. EphB2 knockdown downregulated expression of genes associated with biofunctions cell viability, migration of tumor cells, and invasion of tumor cells. Among the genes most downregulated by EphB2 knockdown were MMP1 and MMP13. Moreover, activation of EphB2 signaling by ephrin-B2-Fc enhanced production of invasion proteinases matrix metalloproteinase-13 (MMP13) and MMP1, and invasion of cSCC cells. These findings provide mechanistic evidence for the role of EphB2 in the early progression of cSCC to the invasive stage and identify EphB2 as a putative therapeutic target in this invasive skin cancer.

Complement factor I promotes progression of cutaneous squamous cell carcinoma.

The incidence of cutaneous squamous cell carcinoma (cSCC) is rising worldwide. We have examined the role of complement components in the progression of cSCC. Analysis of cSCC cell lines (n=8) and normal human epidermal keratinocytes (n=11) with whole transcriptome profiling (SOLiD), quantitative real-time reverse transcriptase-PCR, and western blotting revealed marked overexpression of complement factor I (CFI) in cSCC cells. Immunohistochemical analysis for CFI in vivo showed stronger tumor cell-specific labeling intensity in invasive sporadic cSCCs (n=83) and recessive dystrophic epidermolysis bullosa-associated cSCCs (n=7) than in cSCC in situ (n=65), premalignant epidermal lesions (actinic keratoses, n=64), benign epidermal papillomas (seborrheic keratoses, n=39), and normal skin (n=9). The expression of CFI was higher in the aggressive Ha-ras-transformed cell line (RT3) than in less tumorigenic HaCaT cell lines (HaCaT, A5, and II-4). The expression of CFI by cSCC cells was upregulated by IFN-γ and IL-1ß. Knockdown of CFI expression inhibited proliferation and migration of cSCC cells and resulted in inhibition of basal extracellular signal-regulated kinase (ERK) 1/2 activation. Knockdown of CFI expression potently inhibited growth of human cSCC xenograft tumors in vivo. These results provide evidence for the role of CFI in the progression of cSCC and identify it as a potential therapeutic target in this nonmelanoma skin cancer.

Squamous cell carcinoma of the skin: Emerging need for novel biomarkers.

The incidence of non-melanoma skin cancers (NMSC) is rising worldwide resulting in demand for clinically useful prognostic biomarkers for these malignant tumors, especially for invasive and metastatic cutaneous squamous cell carcinoma (cSCC). Important risk factors for the development and progression of cSCC include ultraviolet radiation, chronic skin ulcers and immunosuppression. Due to the role of cumulative long-term sun exposure, cSCC is usually a disease of the elderly, but the incidence is also growing in younger individuals due to increased recreational exposure to sunlight. Although clinical diagnosis of cSCC is usually easy and treatment with surgical excision curable, it is responsible for the majority of NMSC related deaths. Clinicians treating skin cancer patients are aware that certain cSCCs grow rapidly and metastasize, but the underlying molecular mechanisms responsible for the aggressive progression of a subpopulation of cSCCs remain incompletely understood. Recently, new molecular markers for progression of cSCC have been identified.

Serpin peptidase inhibitor clade A member 1 (SerpinA1) is a novel biomarker for progression of cutaneous squamous cell carcinoma.

The incidence of keratinocyte-derived nonmelanoma skin cancers is increasing worldwide because of cumulative recreational exposure to sunlight. At present, no specific molecular markers are available for assessing the progression of premalignant actinic keratoses to invasive cutaneous squamous cell carcinoma (SCC). We examined the role of the Serpin family in skin SCCs. Expression profiling of cutaneous SCC cell lines (n = 8) revealed up-regulation of SerpinA1 compared with normal epidermal keratinocytes (n = 5). Analysis with quantitative RT-PCR showed that the mean level of SerpinA1 mRNA was markedly up-regulated in cutaneous SCC cell lines (n = 8) compared with in normal keratinocytes. SerpinA1 production by SCC cells was dependent on p38 mitogen-activated protein kinase activity and was up-regulated by epidermal growth factor, tumor necrosis factor-α, interferon-γ, and IL-1ß. Immunostaining of tissue arrays with 148 human tissue samples revealed tumor cell-associated expression of SerpinA1 in 19 of 36 actinic keratoses, 22 of 29 Bowen's disease samples, 67 of 71 sporadic SCCs, and all 12 recessive dystrophic epidermolysis bullosa-associated SCCs examined. Moreover, tumor cell-associated SerpinA1 staining was detected in all chemically induced mouse skin SCCs studied (n = 17). Overexpression of SerpinA1 mRNA was also detected by quantitative RT-PCR in chemically induced mouse skin SCCs (n = 14) compared with control tissues (n = 14). These data identify SerpinA1 as a novel tumor cell-associated biomarker for progression of cutaneous SCCs.

Cutaneous lupus erythematosus after treatment with paclitaxel and bevacizumab for metastatic breast cancer: a case report.

INTRODUCTION: The monoclonal anti-vascular endothelial growth factor antibody bevacizumab is increasingly used in the treatment of several malignant tumors. The usual side effects of this drug are hypertension and proteinuria. Paclitaxel is widely used in the treatment of breast cancer and head and neck carcinomas. Neither of these two drugs typically causes skin disorders. Paclitaxel-related cutaneous lupus erythematosus has been described before, but in earlier cases patients had a history of autoimmune disease. CASE PRESENTATION: We report a case of a 65-year-old Caucasian woman who presented with cutaneous lupus erythematosus after receiving paclitaxel-bevacizumab combination treatment as first-line therapy for metastatic breast cancer. Her cutaneous symptoms and increased serum anti-SSA and anti-SSB antibodies disappeared shortly after the discontinuation of therapy. CONCLUSION: We conclude that cutaneous lupus erythematosus can also be seen in patients without earlier anamnesis of autoimmune disorders and that, furthermore, bevacizumab might cause atypical cutaneous side effects.

Expression of matrix metalloproteinase-1, -7, -9, -13, Ki-67, and HER-2 in epithelial-myoepithelial salivary gland cancer.

BACKGROUND: The expression of matrix metalloproteinases (MMPs) in epithelial-myoepithelial salivary gland carcinoma has not been studied previously. METHODS: Immunohistochemistry for MMP-1, -7, -9, -13, Ki-67, and HER-2, as well as HER-2 gene amplification by silver enhanced in situ hybridization was performed in a series of 12 paraffin-embedded histopathologic samples of patients from Canada and Finland. RESULTS: A positive MMP-13 (p = .0022), higher MMP-13 (p = .0274), and higher MMP-9 (p = .0274) index (multiplication of staining intensity by percentage of the positive cells) predicted better overall survival. In disease-specific analysis, higher MMP-9 index (p = .0327) predicted better survival. A higher volume corrected index (VCI) of Ki-67 (p = .0339) predicted worse disease-specific survival. In 1 patient, HER-2 oncogene amplification was observed. CONCLUSION: MMPs and Ki-67 may have prognostic impact in epithelial-myoepithelial carcinoma.

Matrix metalloproteinase (MMP)-7 in salivary gland cancer.

INTRODUCTION: High levels of certain matrix metalloproteinases (MMPs) have been detected in various human cancers. The purpose of this study was to analyze the expression of MMP-7 in salivary gland cancer (SGC) by immunohistochemistry and to associate the results with the clinical data and the 10-year survival of the SGC patients. MATERIAL AND METHODS: Immunohistochemistry for MMP-7 was performed in a series of 107 paraffin-embedded sections of SGC. The samples represent the entire SGC population in Finland from 1991-1996. Mortality follow-up ended December 31, 2006. RESULTS: The study population of 107 patients consisted of 47 male and 60 female subjects, ranging in age at the time of diagnosis between 23 and 90 years. The minimum follow-up time was 10.6 years and the maximum 15.9 years. By age-adjusted analysis lower staining intensity was associated with worse overall survival of patients with acinic cell carcinoma (p = 0.047, HR 6.5, 95% Cl 1.0-41.7) and in mucoepidermoid carcinoma (p = 0.010, HR 9.3, 95% CI 1.7-50.0). Low staining intensity was also associated with worse disease-specific survival of patients with acinic cell carcinoma (0-1 vs. 2-3; p = 0.047, HR 13.7, 1.0-200.0). VCI Ki-67 was an important prognostic factor for survival of the entire data set (p < 0.0001, HR 4.7, 95% Cl 2.3-9.8). CONCLUSIONS: MMP-7 is associated with the prognosis of patients with acinic cell and mucoepidermoid carcinoma.

Matrix metalloproteinase (MMP)-1, -9 and -13 as prognostic factors in salivary gland cancer.

CONCLUSIONS: In the current study matrix metalloproteinases (MMPs)-9 and -13 were associated with the prognosis in salivary gland cancer (SGC), indicating that they contribute to the progression and invasion of these malignant tumours. OBJECTIVES: Elevated levels of certain MMPs have been detected in various advanced human cancer types. The purpose of the study was to analyse the expression of MMP-1, -9 and -13 in SGC by immunohistochemistry and correlate the results to the clinical data and 10-year survival of SGC patients in a nationwide material. MATERIALS AND METHODS: Immunohistochemistry for MMP-1, -9 and -13 was performed in series of 103 paraffin-embedded sections of SGC. RESULTS: High MMP-13 staining intensity predicted poor survival (3 vs 1; p=0.08) in the whole material studied. High MMP-13 intensity (2+3 vs 1; p=0.05), percentage (2 vs 1; p=0.03) and index (3 vs 1; p=0.02) were associated with poor survival in acinic cell carcinoma. However, high MMP-9 index in adenoid cystic carcinoma (p=0.06) and the percentage of positively staining cells in salivary duct carcinoma patients (p=0.05) was associated with poor survival. High MMP-1 staining intensity (2 vs 0; p=0.06) and index (% x intensity); (2 vs 1, p=0.04) were associated with better overall survival in the whole material.