Total Synthesis of a TNBC-Selective Cytotoxic Bromo Nor-eremophilane, PC-A, and Its Preliminary Structure-Activity Relationships.

PC-A (1), a bromo nor-eremophilane, showed selective antiproliferative activity against a triple-negative breast cancer (TNBC) cell line. This unique activity prompted us to establish a total synthesis to facilitate a structure-activity relationship (SAR) study and selectivity optimization. An enantioselective first total synthesis of 1 was achieved starting from (R)-carvone through a side chain extension with a Mukaiyama aldol reaction and decalin construction. The synthesized decalin derivatives and debromo PC-A (2) were evaluated for antiproliferative activity against five human tumor cell lines, including TNBC, to assess preliminary SAR correlations.

A study of 95 infantile hemangiomas treated with propranolol: A potentially efficacious combination with laser therapy.

We studied 95 patients with infantile hemangioma (IH) treated with propranolol at the Department of Dermatology, Kumamoto University Hospital, from November 2016 to January 2022, based on sex, site, clinical classification, duration of treatment, and residual lesions after treatment. Four of the 95 patients discontinued propranolol due to side effects, and 55 completed follow-ups at our hospital. We observed that 30.1% showed complete resolution of the skin rash, while the remaining 69.8% had erythema or atrophic scarring. Complete resolution occurred in 70% of the cases with the subcutaneous type but only in 15% with the tumor type. Seventeen of the 55 patients who completed follow-ups were treated with propranolol combined with laser therapy. Combined use of propranolol and laser therapy significantly reduced severe erythema compared to the propranolol monotherapy. These results suggest that propranolol therapy in IH often leaves erythema except in the subcutaneous type and that an improvement in erythema can be expected when propranolol is combined with laser therapy.

Serum levels of genomic DNA of α1(I) collagen are elevated in scleroderma patients.

Recent studies have indicated that various nucleic acids are present in human sera, and attracted attention for their potential as novel disease markers in many human diseases. In this study, we tried to evaluate the possibility that DNA and RNA of collagens exist in human sera, and determined whether their serum levels can be useful biomarkers in scleroderma patients. The RNA or DNA of collagens were purified from sera, and detected by polymerase chain reaction or quantitated by real-time polymerase chain reaction. Among approximately 18 360 bases of full-length α1(I) collagen DNA, various regions were detected by polymerase chain reaction in human sera. However, α2(I) collagen DNA, α1(I) collagen RNA or α2(I) collagen RNA were not detectable. α1(I) Collagen DNA in sera was quantitative using our method. The levels of serum α1(I) collagen DNA were significantly increased in scleroderma patients compared with healthy control subjects or systemic lupus erythematosus patients. According to the receiver-operator curve analysis, serum α1(I) collagen DNA levels were shown to be effective as a diagnostic marker of scleroderma. Furthermore, when we determined the association of serum α1(I) collagen DNA levels with clinical/laboratory features in scleroderma patients, those with elevated α1(I) collagen DNA levels showed significantly higher prevalence of pitting scars/ulcers. In summary, elevation of serum α1(I) collagen DNA levels in scleroderma patients may be useful as the diagnostic marker, reflecting the presence of vasculopathy.

Galectin-9 as a Predictive Marker for the Onset of Immune-Related Adverse Effects Associated with Anti-CCR4 MoAb Therapy in Patients with Adult T Cell Leukemia.

Adult T-cell leukemia/lymphoma (ATL/ATLL) is one of the most malignant lymphomas with poor prognosis. ATL/ATLL cells express CC chemokine receptor 4, and mogamulizumab (anti-CCR4 monoclonal antibody) exhibits strong cytotoxicity for ATL/ATLL cells. We analyzed plasma samples of 6 patients with ATL/ATLL treated with chemotherapy followed by mogamulizumab therapy (mogatherapy) for changes in the levels of biomarkers in relation to immune-related adverse effects. As treatment is often associated with skin eruptions, we investigated the profiles of inflammatory cytokines, including galectin-9 (Gal-9), which becomes increased in various infectious diseases and allergic patients. Gal-9, soluble interleukin (IL)-2 receptor, tumor necrosis factor-α, and IL-10 levels were increased before chemotherapy, and Gal-9 levels were associated with the sIL-2 receptor, which reflects tumor burden. Inflammatory levels decreased after chemotherapy. After mogatherapy, 5 of 6 patients attained complete remission (CR), whereas 1 patient showed no response (NR) and died. Among 5 patients with CR, the biomarkers remained low during mogatherapy, except for a 3-5-fold increment in Gal-9 (associated with skin eruptions). A skin biopsy showed infiltration by inflammatory cells and Gal-9 synthesis in areas with CD8 cell infiltration. In the patient with NR, increased levels of Gal-9 and the aforementioned biomarkers were noted 3 days after mogatherapy, followed by opportunistic infections resembling immune reconstitution inflammatory syndrome. Therefore, an increased Gal-9 plasma level in ATL/ATLL indicates tumor burden and reflects immune activation by mogatherapy. These findings may indicate that an increase in the Gal-9 level, a novel immune checkpoint molecule, can reflect immune-related adverse effects of various biotherapies.

Dysregulated interleukin-23 signalling contributes to the increased collagen production in scleroderma fibroblasts via balancing microRNA expression.

OBJECTIVES: The overexpression of IL-12 family cytokines is implicated in the pathogenesis of SSc, but their exact role is still unclear. The aim of this study was to investigate the regulation of extracellular matrix expression by IL-23 and its contribution to the phenotype of SSc. METHODS: The mRNA expression was determined by PCR array and real-time PCR. The expression levels of proteins were determined by immunoblotting and immunohistochemical staining. The effect of IL-23 on dermal fibrosis in vivo was examined in a mouse model of SSc induced by bleomycin injection. RESULTS: Among the IL-12 family members, IL-23 decreased expression of type I collagen protein in cultured normal dermal fibroblasts. We found that miR-4458 and miR-18a mediated the reduction of collagen expression by IL-23. On the contrary, IL-23 up-regulated type I collagen expression in SSc fibroblasts. The paradoxical effects of IL-23 in SSc fibroblasts were also mediated by the balance between miR-4458 and miR-18a expression. Moreover, we revealed that injection of IL-23 into the mouse skin accelerated skin fibrosis. CONCLUSION: This is the first study to report that the balance of two miRNAs is involved in the collagen dysregulation in SSc fibroblasts. Clarification of the regulatory mechanism of tissue fibrosis by IL-23 in SSc skin may lead to a better understanding of this disease and new therapeutic approaches.

Diagnosis of nail psoriasis: evaluation of nail-derived microRNAs as potential novel biomarkers.

BACKGROUND: MicroRNA levels in sera or hair may potentially be useful biomarkers for various diseases. The diagnosis of nail diseases is sometimes difficult, and nail psoriasis without skin lesions is indistinguishable from nail changes caused by other diseases. OBJECTIVES: We evaluated nail microRNA levels as biomarkers for the diagnosis of psoriasis patients. MATERIALS & METHODS: MicroRNA levels were examined in psoriasis patients with (11 patients) and without (six patients) nail changes. Normal control nails were collected from 17 healthy subjects. Eight patients with other diseases who also had nail changes were also included as disease controls. RESULTS: Microarray, real-time PCR, and in situ hybridisation indicated that the expression levels of nail miR-4454 were decreased in psoriasis patients with nail changes, compared to those patients with other diseases involving nail change, or healthy subjects. The miR-4454 levels in nails showed a significant inverse correlation with the Nail Psoriasis Severity Index (NAPSI) score, suggesting that nail miR-4454 levels reflect nail condition. CONCLUSION: The levels of microRNAs in nails may be suitable biomarkers for diagnosis or evaluation of disease activity of psoriasis.

Altered expression of CD63 and exosomes in scleroderma dermal fibroblasts.

BACKGROUND: Exosomes are small vesicles shed from various cells. They contain proteins, lipids, and nucleic acids, and are regarded as a tool of cell-cell communication. OBJECTIVES: To reveal the putative role of exosomes in systemic sclerosis (SSc), and to elucidate the effect of exosomes on wound healing. METHODS: The expression of common markers for exosomes (CD63, CD9, and CD81) and type I collagen were examined with real-time PCR, immunohistochemical analysis, ELISA, immunoblotting, and flow cytometry. The effect of serum-derived exosomes on wound healing was tested on full-thickness wounds in the mid-dorsal skin of BALB/c mice. RESULTS: The expression levels of CD63 as well as CD9 and CD81 tended to be increased in SSc dermal fibroblasts compared to normal fibroblasts. Increased exosomes in a cultured media of SSc fibroblasts stimulated the expression levels of type I collagen in normal fibroblasts. As the mechanism, collagen-related microRNA levels in SSc fibroblast-derived exosomes were dysregulated, indicating that both the amount and the content of exosomes were altered in SSc. On the other hand, SSc sera showed significantly decreased exosome levels compared to normal sera. The frequencies of vascular involvements, including skin ulcers or pitting scars, were significantly increased in patients with decreased serum exosome levels. The healing of mice wounds was accelerated by treatment with serum-derived exosomes. CONCLUSIONS: Vascular abnormalities in SSc may account for the decreased serum exosome levels by the disturbed transfer of exosomes from the skin tissue to the blood stream. Our study suggests the possibility that SSc patients with vascular involvements have decreased serum exosome levels, which causes the delay of wound healing due to down-regulation of collagen, resulting in higher susceptibility to pitting scars and/or ulcers. Exosome research will lead to a detailed understanding of SSc pathogenesis and new therapeutic approaches.

Long non-coding RNA TSIX is upregulated in scleroderma dermal fibroblasts and controls collagen mRNA stabilization.

Long non-coding RNAs (lncRNAs) are thought to have various functions other than RNA silencing. We tried to evaluate the expression of lncRNAs in patients with systemic sclerosis (SSc) and determined whether lncRNAs controls collagen expression in dermal fibroblasts. lncRNA expression was determined by real-time PCR and in situ hybridization. Protein and mRNA levels of collagen were analysed using immunoblotting and real-time PCR. We found TSIX, one of the lncRNAs, was overexpressed in SSc dermal fibroblasts both in vivo and in vitro, which was inhibited by the transfection of transforming growth factor (TGF)-ß1 siRNA. TSIX siRNA reduced the mRNA expression of type I collagen in normal and SSc dermal fibroblasts, but not the levels of major disease-related cytokines. In addition, TSIX siRNA significantly reduced type I collagen mRNA stability, but not protein half-lives. Furthermore, we first investigated serum lncRNA levels in patients with SSc, and serum TSIX levels were significantly increased in SSc patients. TSIX is a new regulator of collagen expression which stabilizes the collagen mRNA. The upregulation of TSIX seen in SSc fibroblasts may result from activated endogenous TGF-ß signalling and may play a role in the constitutive upregulation of collagen in these cells. Further studies on the regulatory mechanism of tissue fibrosis by lncRNAs in SSc skin lead to a better understanding of the pathogenesis, new diagnostic methods by their serum levels and new therapeutic approaches using siRNAs.

EBI3 Downregulation Contributes to Type I Collagen Overexpression in Scleroderma Skin.

IL-12 family cytokines are implicated in the pathogenesis of various autoimmune diseases, but their role in the regulation of extracellular matrix expression and its contribution to the phenotype of systemic sclerosis (SSc) remain to be elucidated. Among the IL-12 family members, IL-35 decreases type I collagen expression in cultured dermal fibroblasts. IL-35 consists of p35 and EBI3 subunits, and EBI3 alone could downregulate the protein and mRNA expression of type I or type III collagen in the presence or absence of TGF-ß costimulation. We found that collagen mRNA stability was reduced by EBI3 via the induction of miR-4500. The IL-35 levels in the sera or on the surface of T cells were not altered in SSc patients, while EBI3 expression was decreased in the keratinocytes of the epidermis and regulatory T cells of the dermis in SSc skin compared with normal skin, which may induce collagen synthesis in SSc dermal fibroblasts. We also found that gp130, the EBI3 receptor, was expressed in both normal and SSc fibroblasts. Moreover, we revealed that EBI3 supplementation by injection into the skin improves mice skin fibrosis. Decreased EBI3 in SSc skin may contribute to an increase in collagen accumulation and skin fibrosis. Clarifying the mechanism regulating the extracellular matrix expression by EBI3 in SSc skin may lead to better understanding of this disease and new therapeutic strategies using ointment or microinjection of the subunit.

Mice overexpressing integrin αv in fibroblasts exhibit dermal thinning of the skin.

BACKGROUND: Integrins, especially αv integrin (ITGAV), are thought to play central roles in tissue fibrosis and the pathogenesis of scleroderma. So far, skin phenotype of tissue-specific transgenic mice of ITGAV have not been investigated. OBJECTIVE: To investigate the role of ITGAV in the skin fibrosis, we engineered transgenic mice that overexpress ITGAV in the fibroblasts under the control of the COL1A2 enhancer promoter. METHODS: Protein or RNA expression was evaluated by real-time PCR, immunohistochemistry, immunoblotting and immunoprecipitation. RESULTS: Dermal thickness and Masson's trichrome staining were decreased in ITGAV transgenic (Tg) mice compared with wild-type (WT) mice. Protein and mRNA levels of COL1A2, COL3A1, CTGF and integrin ß3 were down-regulated in the skin of Tg mice. In addition, the cell proliferation of cultured dermal fibroblasts obtained from Tg mice skin was decreased compared to those of WT mice. FAK phosphorylation was reduced in fibroblasts cultured from Tg mice skin in comparison to WT mice fibroblasts. Integrin ß3 siRNA inhibited FAK phosphorylation levels, while FAK inhibitor reduced the expression of collagens and CTGF in mice dermal fibroblasts. CONCLUSIONS: The down-regulation of collagen or CTGF by decreased integrin ß3 and FAK phosphorylation may cause the dermal thinning in Tg mice. Lower CTGF may also result in reduced growth of Tg mice fibroblasts. Our hypothesis is that the balance between α and ß chain of integrins positively or negatively control collagen expression and dermal thickness. This study gave a new insight in the treatment of tissue fibrosis and scleroderma by balancing integrin expression.

MIRSNP rs2910164 of miR-146a is associated with the muscle involvement in polymyositis/dermatomyositis.

BACKGROUND: Recently, single nucleotide polymorphisms (SNPs) located in microRNAs, the so-called MIRSNPs, have attracted attention for their possible involvement in the pathogenesis of various diseases. Such MIRSNPs may have a functional role, due to the alteration of microRNA function, and can be a disease marker. In this study, we evaluated the possibility that MIRSNP rs2910164 in miR-146a can be a useful marker for the diagnosis and evaluation of disease activity of polymyositis/dermatomyositis (PM/DM).Methods DNA was obtained from 25 patients with DM, 16 with clinically amyopathic DM,and three with PM, and genotyped by polymerase chain reaction (PCR). The PCR products were digested by MnlI, and the digested products were run out on a 3% agarosegel. Serum levels of miR-146a were measured by real-time PCR.Results We could not find a significant difference in the frequency of genotype distribution between controls and patients with PM/DM. However, the frequency of muscle weakness and dysphagia in patients with CC genotype was significantly higher as compared with patients with CG or GG genotype. In addition, the minimum free energy between miR-146a and its complementary strand with G allele is estimated at −26.8 kcal/mol, while that of Callele is at −24.0 kcal/mol, suggesting that the MIRSNP rs2910164 is functional. Serum miR-146a levels tended to be decreased in patients with DM with the CC genotype.Conclusions Taken together, miR-146a may be involved in the pathogenesis of PM/DM, and patients with the CC genotype are at higher risk of muscle involvement.

Decreased interleukin-20 expression in scleroderma skin contributes to cutaneous fibrosis.

OBJECTIVE: To clarify the role of interleukin-20 (IL-20) in the regulatory mechanism of extracellular matrix expression and to determine the contribution of IL-20 to the phenotype of systemic sclerosis (SSc). METHODS: Protein and messenger RNA (mRNA) levels of collagen, Fli-1, IL-20, and IL-20 receptor (IL-20R) were analyzed using polymerase chain reaction (PCR) array, immunoblotting, immunohistochemical staining, enzyme-linked immunosorbent assay, and real-time PCR. RESULTS: PCR array revealed that IL-20 decreased gene expression of α2(I) collagen (0.03-fold), Smad3 (0.02-fold), and endoglin (0.05-fold) in cultured normal dermal fibroblasts. Fli-1 protein expression was induced by IL-20 (~2-fold). The inhibition of collagen by IL-20, the induction of Fli-1 by IL-20, and the reduction of Smad3 and endoglin by IL-20 were also observed in SSc fibroblasts. Serum IL-20 levels were reduced only slightly in SSc patients but were significantly decreased in patients with scleroderma spectrum disorders (the prodromal stage of SSc) compared with those in normal subjects (111.3 pg/ml versus 180.4 pg/ml; P < 0.05). On the other hand, IL-20 mRNA expression in SSc skin was decreased compared with that in normal skin (P < 0.05), which may result in the induction of collagen synthesis in SSc dermal fibroblasts. IL-20R was expressed in normal and SSc fibroblasts. Moreover, IL-20 supplementation by injection into the skin reversed skin fibrosis induced by bleomycin in mice (~0.5-fold). CONCLUSION: IL-20 reduces basal collagen transcription via Fli-1 induction, while down-regulation of Smad3 and endoglin may cancel the effect of transforming growth factor ß in SSc fibroblasts. To confirm the therapeutic value of IL-20 and IL-20R, their function and expression in vivo should be further studied.

Hair miR-29a levels are decreased in patients with scleroderma.

In the present study, we evaluated the possibility that we can utilize hair shaft miR-29a levels as disease marker of scleroderma. Hair samples were obtained from 20 scleroderma patients, five dermatomyositis patients and 13 controls. microRNAs were purified from hairs as well as skins or sera, and miR-29a levels were measured with quantitative real-time polymerase chain reaction. Mean hair miR-29a levels in scleroderma patients were significantly lower than those in control subjects or dermatomyositis, while expression levels of hair shaft marker keratin 34 were similar among them. There was no strong correlation among the miR-29a levels in the hair, skin and serum of each patient, suggesting that hair microRNAs can be independent biomarkers. We found scleroderma patients with decreased miR-29a levels had contracture of the phalanges at a significantly higher prevalence than those without. To confirm the clinical usefulness of hair microRNAs, large-scale researches are needed in the future.

Detection of hair-microRNAs as the novel potent biomarker: evaluation of the usefulness for the diagnosis of scleroderma.

BACKGROUND: Serum microRNA levels are known as useful biomarkers for various diseases. Recent publication has indicated the existence of microRNAs in hair roots and hair shafts. OBJECTIVE: In this study, we evaluated several methods for the extraction of hair microRNAs, and their usefulness for the diagnosis of scleroderma. METHODS: A single hair root and 5 pieces of hair shafts were obtained from the occiput of each individual of 11 scleroderma patients and 13 normal subjects at the time of serum sampling. microRNA extraction from sera or hair roots was performed with commercially available kits. microRNAs were extracted from hair shafts using four different methods. microRNA expression was evaluated by PCR array and real-time PCR. RESULTS: We demonstrated microRNAs in hair roots and hair shafts were detectable and quantitative using our method. We found the difference of microRNA levels in hair roots and hair shafts obtained from different places of head in each individual were within 2-fold, indicating the reproducibility of hair microRNA levels by our method. PCR array revealed microRNAs from sera, hair roots and hair shafts have different expression pattern, and can be independent biomarkers. Serum and hair root miR-196a levels were not significantly changed in scleroderma patients, while we found miR-196a levels in hair shafts were significantly decreased in scleroderma patients compared to those in normal subjects (p<0.05). CONCLUSION: Hairs are more accessible than sera among human samples. microRNAs levels in hair roots or hair shafts may become effective and independent biomarkers.

Expression analysis of multiple microRNAs in each patient with scleroderma.

In this study, we compared expression pattern of multiple microRNAs in individual patient with scleroderma with that in normal subject. Serum levels of six microRNAs (miR-7 g, miR-21, miR-29b, miR-125, miR-145 and miR-206) were evaluated using real-time PCR in 15 patients with scleroderma and 15 normal subjects. While levels of the six microRNAs were similar between the two groups, we found significant difference in the ranks between miRNAs in patients with scleroderma. Additionally, levels of let-7 g and miR-125b showed strong and significant correlation in normal subjects, but not in patients with scleroderma. Thus, miRNA expression pattern may be different in patients with scleroderma. We also found the combination of serum levels of miR-206 and miR-21 was more useful in distinguishing patients with scleroderma from normal subjects than either miR-206 or miR-21 alone. Our study is the first to demonstrate different expression profiles of multiple microRNAs in each patient with scleroderma and examine its clinical significance.

Down-regulation of miR-223 contributes to the formation of Gottron's papules in dermatomyositis via the induction of PKCɛ.

BACKGROUND: Dermatomyositis (DM) is characterized by skin manifestations accompanying and preceding muscle weakness. Gottron's papules, one of the skin manifestations, are of great diagnostic value because they are specific to DM. However, the pathogenesis of Gottron's papules remains unclear. OBJECTIVES: We investigated the expression pattern of miRNAs in Gottron's papules of DM patients and evaluated the possibility that miRNAs play a role in its pathogenesis. MATERIALS AND METHODS: miRNAs were extracted from skin tissues and sera of patients with DM, clinically amyopathic DM (CADM) and healthy controls. To identify pathogenic miRNAs, we performed miRNA PCR array analysis. The results were confirmed by in situ hybridization, immunohistochemistry, immunoblotting and transient transfection of siRNAs or miRNA inhibitors. RESULTS: PCR array analysis using tissue miRNAs demonstrated the miR-223 level was markedly decreased in Gottron's papules of DM and CADM in vivo, but not in psoriasis skin. The protein expression of PKCɛ, a predicted target of miR-223, was increased in DM/CADM skin. The transfection of a specific inhibitor of miR-223 in keratinocytes led to up-regulation of the PKCɛ protein, and resulted in increased cell proliferation. On the other hand, cell numbers were significantly decreased when cells were transfected with siRNA for PKCɛ. The serum miR-223 concentration was decreased in DM/PM patients, particularly in CADM patients, compared with healthy controls. CONCLUSIONS: A decreased miR-223 expression and the subsequently increased PKCɛ levels may therefore play a key role in the pathogenesis of Gottron's papules.

Serum levels of leptin receptor in patients with systemic sclerosis.

Microvascular damage is one of the primary pathologic components of systemic sclerosis (SSc). Serological abnormalities of angiogenic and angiostatic factors in SSc have previously been described. Like these factors, the plasma levels of leptin were significantly elevated in patients with SSc in comparison to normal controls. However, leptin receptor has not been examined in patients with SSc. The current study used sandwich ELISA to evaluate the serum levels of leptin receptor in patients with SSc. Serum samples were obtained from 36 patients with SSc. Samples were also obtained from 12 healthy control subjects and 10 patients with scleroderma spectrum disorder (SSD) who did not fulfill the criteria for SSc but who had the potential to develop SSc. Mean serum leptin receptor levels were significantly higher in patients with SSD than in patients with SSc (255.7 ng/mL vs. 184.6 ng/mL, p < 0.05 according to a Mann-Whitney test). There were no statistically significant differences between healthy control subjects and patients with SSc. Clinical parameters were evaluated, and the frequency of esophageal reflux was significantly lower in patients with elevated serum leptin receptor levels than in those with reduced levels (6.3% vs. 35.3%, p < 0.05). In summary, these results suggest that the serum levels of leptin receptor are a clinically useful marker of SSD, and measurement of serum leptin receptor over time in patients with SSD may lead to early detection of SSc.

Decreased miR-7 expression in the skin and sera of patients with dermatomyositis.

Expression of microRNA (miRNA) in the skin in dermatomyositis has not previously been studied in detail. In this study, we performed miRNA array analysis using miRNAs purified from dermatomyositis-involved skin and normal skin, and found that several miRNAs were up- or down-regulated in dermatomyositis skin. Among them, we focused on miR-7, one of the most down-regulated miRNAs in dermatomyositis skin. Total miRNAs were purified from serum, and hsa-miR-7 levels were measured with quantitative real-time PCR using the specific primer. Serum levels of miR-7 were significantly decreased in patients with dermatomyositis compared with normal subjects or patients with other autoimmune diseases. Thus, serum miR-7 levels might be a possible diagnostic marker for dermatomyositis. Clarifying the up- or down-stream events of down-regulated miR-7 in patients with dermatomyositis may lead to further understanding of the disease and a new therapeutic approach.

microRNA-7 down-regulation mediates excessive collagen expression in localized scleroderma.

Localized scleroderma (LSc), a connective tissue disorder restricted to the skin and subcutaneous tissue, is characterized by skin fibrosis due to an excessive deposition of types I collagen. The mechanism of such fibrosis is still unknown, but epigenetics may play some roles in the excessive collagen expression. In the present study, we investigated the mechanism of fibrosis seen in LSc, focusing on microRNA (miRNA). miRNA expression was determined by PCR array, real-time PCR, and in situ hybridization. The function of miRNA was evaluated using specific inhibitor. Immunoblotting was performed to detect α2(I) collagen protein. PCR array analysis using tissue miRNA demonstrated miR-7 level was significantly decreased in LSc skin as well as keloid tissue compared to normal skin in vivo. In situ hybridization also showed miR-7 expression in dermal fibroblasts was decreased in LSc dermis. The transfection of specific inhibitor for miR-7 into cultured normal dermal fibroblasts resulted in the up-regulation of α2(I) collagen protein in vitro. Also, the serum levels of miR-7 were significantly decreased in LSc patients compared with healthy controls, but serum miR-29a levels not. Systemic or local down-regulation of miR-7 may contribute to the pathogenesis of LSc via the overexpression of α2(I) collagen, and serum miR-7 may be useful as a disease marker. Investigation of the regulatory mechanisms of LSc by miRNA may lead to new treatments by the transfection into the lesional skin of this disease.