Benign Fibroproliferative Tumors Research Articles

Low-Frequency Ultrasound Sensitive Piezo1 Channels Regulate Keloid-Related Characteristics of Fibroblasts.

Keloids are benign fibroproliferative tumors that severely diminish the quality of life due to discomfort, dysfunction, and disfigurement. Recently, ultrasound technology as a noninvasive adjuvant therapy is developed to optimize treatment protocols. However, the biophysical mechanisms have not yet been fully elucidated. Here, it is proposed that piezo-type mechanosensitive ion channel component 1 (Piezo1) plays an important role in low-frequency sonophoresis (LFS) induced mechanical transduction pathways that trigger downstream cellular signaling processes. It is demonstrated that patient-derived primary keloid fibroblasts (PKF), NIH 3T3, and HFF-1 cell migration are inhibited, and PKF apoptosis is significantly increased by LFS stimulation. And the effects of LFS is diminished by the application of GsMTx-4, the selective inhibitor of Piezo1, and the knockdown of Piezo1. More importantly, the effects of LFS can be imitated by Yoda1, an agonist of Piezo1 channels. Establishing a patient-derived xenograft keloid implantation mouse model further verified these results, as LFS significantly decreased the volume and weight of the keloids. Moreover, blocking the Piezo1 channel impaired the effectiveness of LFS treatment. These results suggest that LFS inhibits the malignant characteristics of keloids by activating the Piezo1 channel, thus providing a theoretical basis for improving the clinical treatment of keloids.

Analysis and Identification of Methylation‐Modifying Genes Associated with Hypoxia and Immunity in Keloids

Background. Keloids are benign fibroproliferative tumors that are unique to humans. However, the exact mechanism of keloid formation remains unclear. The inflammatory cytokines released by immune cells can activate fibroblasts, connective tissue cell proliferation, and angiogenesis. Hypoxia is common in the process of fibrosis in many diseases. This study aimed to investigate the relationship between immune response, hypoxia, and keloid formation. Methods. Gene methylation and expression data were downloaded from the GEO database. Thereafter, differentially methylated genes associated with immunity and hypoxia were identified. Machine learning was performed to identify potential diagnostic/immunity/hypoxia‐related differentially methylated/expressed genes, followed by analysis of functional enrichment, transcription factors, protein‐protein interactions, and expression validation by reverse transcription quantitative polymerase chain reaction and immunohistochemistry. Results. In total, 16 immunity/hypoxia‐related hypermethylated low‐expression genes and 18 immunity/hypoxia‐related hypomethylated high‐expression genes were identified in keloids. Based on machine learning, nine differentially methylated and expressed genes were selected as potential diagnostic markers for keloids, including two hypoxia‐related genes (CDKN1A and PGAM2) and seven immunity‐related genes (DCD, PTGDS, WFIKKN1, SEMA5A, IL1R1, ITGAL, and SOS1). Some significantly enriched signaling pathways were identified, including the FoxO, PI3K‐Akt, focal adhesion, and ErbB signaling pathways. SOS1 is involved in disease regulation with 65 transcription factors and has a higher interaction score with other molecules. Conclusions. Two hypoxia‐related genes (CDKN1A and PGAM2) and seven immunity‐related genes (DCD, PTGDS, WFIKKN1, SEMA5A, IL1R1, ITGAL, and SOS1) could be considered potential diagnostic markers for keloids, and may be helpful in understanding the importance of oxygen balance and immune regulation in keloids.

Circ_0008450 regulates keloid-derived fibroblast proliferation, migration, invasion and apoptosis with increased IGFBP5 through sponging miR-1224-5p

BackgroundKeloids (KD) are benign fibroproliferative tumors and circular RNAs (circRNAs) may participate in KD progression. At present, whether circ_0008450 regulates keloid-derived fibroblast phenotypes remains unclear. This study aimed to explore the functions of circ_0008450 in keloid (KD)-derived fibroblast phenotypes and the underlying mechanism. MethodsQuantitative real-time polymerase chain reaction (qRT-PCR) or western blot assay was performed to determine the expression of circ_0008450, miR-1224-5p, insulin like growth factor binding protein 5 (IGFBP5) and extracellular matrix (ECM)-related markers. 5-Ethynyl-2′-deoxyuridine (EdU) assay was conducted to assess cell proliferation ability. Flow cytometry analysis was used to analyze cell cycle and cell apoptosis. Scratch assay and transwell assay were utilized to examine cell migration and invasion. Mechanism assays were executed to verify the relations of circ_0008450, miR-1224-5p and IGFBP5. ResultsCirc_0008450 was highly expressed in KD tissues and KD-derived fibroblasts. Circ_0008450 silencing inhibited KD-derived fibroblast proliferation, cell cycle, and motility and promoted apoptosis. The effect of circ_0008450 knockdown on KD-derived fibroblast processes was ameliorated by miR-1224-5p downregulation. IGFBP5 was a target gene of miR-1224-5p. IGFBP5 upregulation abated miR-1224-5p-mediated effects on KD-derived fibroblast processes. ConclusionCirc_0008450 promoted KD-derived fibroblast proliferation, migration, and invasion and repressed apoptosis via sponging miR-1224-5p and elevating IGFBP5.

EGR1/NOX4 pathway regulates oxidative stress and further facilitates fibrosis progression in keloids responses to TGF-β1

BackgroundAs classic benign fibroproliferative tumors, keloids remain a major therapeutic challenge due to their complex pathological mechanisms. ObjectiveTo determine the functional role of transforming growth factor β1 (TGF-β1)/early growth response factor-1 (EGR1)/NADPH oxidases 4 (NOX4) axis in the pathogenesis of keloid fibrosis. MethodsDifferentially expressed genes in keloid tissues and normal skins were analyzed by RNA sequencing. Then, the human skin fibroblast cell line was treated with TGF-β1 at a dose of 10 ng/mL in order to stimulate the TGF-β1/SMAD pathway and the pathway was blocked using the SB431542. Furthermore, EGR1/NOX4 was over-expressed and inhibited by transfecting overexpression plasmids and small interfering RNAs, respectively. The levels of intracellular reactive oxygen species were measured using the DCFH-DA assay, and the expression levels of fibrosis‐related genes were assessed by Western blot analysis. Alternately, dual-luciferase reporter analysis verified the targeting relationship between EGR1 and NOX4. ResultsThe TGF-β1/SMAD signaling pathway was significantly activated in keloid tissues to promote dermal fibrosis. The level of ROS was increased in keloid fibroblasts. Moreover, TGF-β1 could facilitate the expression of EGR1 through regulating the SMAD pathway in keloids and promoting the fibrotic phenotype of keloid fibroblasts. EGR1 could regulate the production of ROS by targeting NOX4. Furthermore, NOX4-derived ROS could promote fibrotic-like phenotype of keloid fibroblasts and play an important role in keloid fibrosis. ConclusionOur findings provide new insights into the mechanisms of the TGF-β1/EGR1/NOX4 pathway in keloid fibrosis, and the TGF-β1/EGR1/NOX4 axis may serve as a potential therapeutic target for keloids.

611 Transcriptomic differences between surgical and non-surgical keloids

Keloids are benign fibroproliferative tumors with features of raised scar tissue and excessive growth beyond the original border. Keloid scars show excessive extracellular matrix(ECM) deposition and rich vasculature. Recently, many studies have revealed the important pathways of keloid pathogenesis. Herein, we focus on the difference between traumatic and nontraumatic keloids in a transcriptomic level. To preclude intra-lesional heterogeneity, whole tissue was used for bulk RNA-sequencing. Three trauma induced keloids and 4 non-trauma related keloids were achieved by surgical excision from 7 different patients.

Downregulation of PLK4 expression induces apoptosis and G0/G1-phase cell cycle arrest in keloid fibroblasts.

ObjectivesKeloids are benign fibroproliferative tumors that display many cancer‐like characteristics, such as progressive uncontrolled growth, lack of spontaneous regression, and extremely high rates of recurrence. Polo‐like kinase 4 (PLK4) was recently identified as a master regulator of centriole replication, and its aberrant expression is closely associated with tumorigenesis. This study aimed to investigate the expression and biological role of PLK4 in the pathogenesis of keloids.Materials and MethodsWe evaluated the expression of PLK4 in keloids and adjacent normal skin tissue samples. Then, we established PLK4 knockdown and overexpression cell lines in keloid fibroblasts (KFs) and normal skin fibroblasts (NFs), respectively, to investigate the roles of PLK4 in the regulation of proliferation, migration, invasion, apoptosis, and cell cycle in KFs. Centrinone B (Cen‐B), a highly selective PLK4 inhibitor, was used to inhibit PLK4 activity in KFs to evaluate the therapeutic effect on KFs.ResultsWe discovered that PLK4 was overexpressed in keloid dermal samples and KFs compared with adjacent normal skin samples and NFs derived from the same patients. High PLK4 expression was positively associated with the proliferation, migration, and invasion of KFs. Furthermore, knockdown of PLK4 expression or inhibition of PLK4 activity by Cen‐B suppressed KF growth, induced KF apoptosis via the caspase‐9/3 pathway, and induced cell cycle arrest at the G0/G1 phase in vitro.ConclusionsThese findings demonstrate that PLK4 is a critical regulator of KF proliferation, migration, and invasion, and thus, Cen‐B is a promising candidate drug for keloid treatment.

NEAT1 Knockdown Inhibits Keloid Fibroblast Progression by miR-196b-5p/FGF2 Axis

BackgroundKeloid is a benign fibroproliferative tumor of the skin caused by abnormal wound healing process after skin injury. Long noncoding RNAs have been reported to be involved in the development of keloid. However, the role and mechanism of nuclear enriched abundant transcript 1 (NEAT1) in keloid are still unknown. MethodsQuantitative real-time polymerase chain reaction was performed to detect the expression of NEAT1, miR-196b-5p, and fibroblast growth factor 2 (FGF2). Western blot was conducted to measure the levels of collagen I, α-smooth muscle actin, fibronectin, and FGF2. Cell Counting Kit-8 assay and transwell assay were used to evaluate cell viability and migration, respectively. Dual-luciferase reporter assay was conducted to verify the targeting relationship between miR-196b-5p and NEAT1 or FGF2. ResultsNEAT1 was increased and miR-196b-5p was decreased in keloid tissues and fibroblasts. NEAT1 knockdown or miR-196b-5p overexpression suppressed cell viability, migration, and extracellular matrix (ECM) component production in keloid fibroblasts. MiR-196 b-5p was a target of NEAT1, and NEAT1 overexpression reversed the effect of miR-196b-5p on keloid fibroblast progression. Moreover, we found that miR-196b-5p directly targeted FGF2. FGF2 knockdown suppressed keloid fibroblast viability, migration, and ECM protein production. FGF2 overexpression abolished the effect of miR-196b-5p overexpression on keloid fibroblast development. ConclusionsNEAT1 silencing suppressed cell viability, migration, and ECM expression in keloid fibroblasts by regulating miR-196b-5p/FGF2 axis, indicating a promising strategy for keloid treatment.

Identification of Differentially Methylated CpG Sites in Fibroblasts from Keloid Scars.

As a part of an abnormal healing process of dermal injuries and irritation, keloid scars arise on the skin as benign fibroproliferative tumors. Although the etiology of keloid scarring remains unsettled, considerable recent evidence suggested that keloidogenesis may be driven by epigenetic changes, particularly, DNA methylation. Therefore, genome-wide scanning of methylated cytosine-phosphoguanine (CpG) sites in extracted DNA from 12 keloid scar fibroblasts (KF) and 12 control skin fibroblasts (CF) (six normal skin fibroblasts and six normotrophic fibroblasts) was conducted using the Illumina Human Methylation 450K BeadChip in two replicates for each sample. Comparing KF and CF used a Linear Models for Microarray Data (Limma) model revealed 100,000 differentially methylated (DM) CpG sites, 20,695 of which were found to be hypomethylated and 79,305 were hypermethylated. The top DM CpG sites were associated with TNKS2, FAM45B, LOC723972, GAS7, RHBDD2 and CAMKK1. Subsequently, the most functionally enriched genes with the top 100 DM CpG sites were significantly (p ≤ 0.05) associated with SH2 domain binding, regulation of transcription, DNA-templated, nucleus, positive regulation of protein targeting to mitochondrion, nucleoplasm, Swr1 complex, histone exchange, and cellular response to organic substance. In addition, NLK, CAMKK1, LPAR2, CASP1, and NHS showed to be the most common regulators in the signaling network analysis. Taken together, these findings shed light on the methylation status of keloids that could be implicated in the underlying mechanism of keloid scars formation and remission.

733 SFRP2-expressing, COL11A1-expressing fibroblasts are the major fibroblast population within keloids

Fibroblasts perform a multitude of processes within skin: extracellular matrix (ECM) production, regulation of inflammation, facilitate cutaneous repair after injury, and serve as pluripotent mesenchymal cells. Recent evidence suggests that there are two main major fibroblast populations in human skin: SFRP2-expressing fibroblasts and FMO1-expressing fibroblasts, and five minor populations, each expressing discrete genes: CRABP1, COL11A1, FMO2, PRG4, or C2ORF40. Keloids are benign fibroproliferative tumors that result from an exaggerated response to cutaneous wound healing.

Improving the anti-keloid outcomes through liposomes loading paclitaxel-cholesterol complexes.

Keloids represent benign fibroproliferative tumors which result from elevated expression of inflammation. Paclitaxel (PTX) was an effective chemotherapeutic agent and has been reported to have anti-fibrotic effects, but the strong hydrophobicity brings a challenge for its clinical application. The objective of this study was to improve the water solubility of PTX and investigate its anti-keloid effects. We prepared a PTX-cholesterol-loaded liposomes (PTXL) by thin film evaporation fashion and characterized their physicochemical properties. We also investigated the effects of PTX on proliferation, invasion and fibrosis of keloid fibroblasts in vitro and in vivo. The prepared PTXL have a spherical appearance, a particle size of 101.43 nm and a zeta potential of -41.63 mV. PTXL possessed a high drug entrapment efficiency of 95.63% and exhibited a good stability within 30 days. The drugs in PTXL were released in a slow and sustained mode. The PTXL could be effectively uptaken into human keloids fibroblast (HKFs) in a time-dependent manner. In vitro, PTXL showed better ability on inhibiting cell proliferation, migration and invasion, and effectively on promoting apoptosis and arresting cell cycle in G2/M phase compared to PTX. Meanwhile, in vivo studies indicated that the PTXL had better performance on inhibiting the keloids growth compared to the PTX in keloid-bearing BALB/c nude mice model. Finally, we found PTX treatment suppressed the production of tumor necrosis factor alpah (TNF-α), interleukin 6 (IL-6) and transforming growth factor beta (TGF-β) and inhibited the expression of alpha smooth muscle actin (α-SMA) and collagen I in HKFs. The activation of protein kinase B (AKT)/glycogen synthase kinase 3 beta (GSK3β) signaling pathway also blocked by PTX in cultured HKFs and keloid tissues. LY294002, a PI3K (phosphatidylinositol 3-kinase)/AKT inhibitor, also suppressed the expression of TNF-α, IL-6 and TGF-β, and simultaneously, reduced the production of α-SMA and collagen I in HKFs. The inhibition of AKT/GSK3β signaling pathway contribute to inhibit the generation of fibrogenic cytokines by PTXL on ameliorating fibrosis progress in keloids. Our results suggested that the developed PTXL would become a promising therapeutic agent in the field of anti-keloid therapy.

Aberrant connective tissue differentiation towards cartilage and bone underlies human keloids in African Americans.

Keloids are benign fibroproliferative tumors more frequently found among African Americans. Until now, keloid etiopathogenesis is not fully understood. To characterize keloids in African Americans, we performed transcriptional profiling of biopsies from large chronic keloids, adjacent non-lesional (NL) skin (n=3) and a newly formed keloid lesion using Affymetrix HGU133 2.0 plus arrays. Quantitative RT-PCR (qRT-PCR) and immunohistochemistry (IHC) staining were performed to confirm increased expression of relevant genes. We identified 1202 upregulated and 961 downregulated differentially expressed genes (DEGs) between keloid and NL skin; 1819 up- and 1867 downregulated DEGs between newly formed keloid and NL skin; and 492 up- and 775 downregulated DEGs between chronic and newly formed keloid (fold change >2, false discovery rate <0.05). Many of the top upregulated DEGs between chronic keloid and NL skin and between newly formed keloid and NL skin are involved in bone/cartilage formation including Fibrillin 2 (FBN2), Collagen type X alpha 1, Asporin (ASPN), Cadherin 11 (CDH11), Bone morphogenic protein 1 (BMP1), Secreted phosphoprotein 1 and Runt-related transcription factor 2 (RUNX2). qRT-PCR confirmed significant (P<.05) upregulation of BMP1, RUNX2, CDH11 and FBN2 in chronic keloid compared to NL skin. IHC staining showed increased protein expression of ASPN, CDH11, BMP1 and RUNX2 on chronic and newly formed keloid compared to NL skin. Our study shows that large keloids in African Americans represent a dysplasia of cutaneous connective tissue towards immature cartilage or bone differentiation. The phenotype is potentially regulated by overexpression of RUNX2. This knowledge may give insights to guide the development of better treatment for the disease in the future.

Genome-Wide Scan for Methylation Profiles in Keloids.

Keloids are benign fibroproliferative tumors of the skin which commonly occur after injury mainly in darker skinned patients. Medical treatment is fraught with high recurrence rates mainly because of an incomplete understanding of the biological mechanisms that lead to keloids. The purpose of this project was to examine keloid pathogenesis from the epigenome perspective of DNA methylation. Genome-wide profiling used the Infinium HumanMethylation450 BeadChip to interrogate DNA from 6 fresh keloid and 6 normal skin samples from 12 anonymous donors. A 3-tiered approach was used to call out genes most differentially methylated between keloid and normal. When compared to normal, of the 685 differentially methylated CpGs at Tier 3, 510 were hypomethylated and 175 were hypermethylated with 190 CpGs in promoter and 495 in nonpromoter regions. The 190 promoter region CpGs corresponded to 152 genes: 96 (63%) were hypomethylated and 56 (37%) hypermethylated. This exploratory genome-wide scan of the keloid methylome highlights a predominance of hypomethylated genomic landscapes, favoring nonpromoter regions. DNA methylation, as an additional mechanism for gene regulation in keloid pathogenesis, holds potential for novel treatments that reverse deleterious epigenetic changes. As an alternative mechanism for regulating genes, epigenetics may explain why gene mutations alone do not provide definitive mechanisms for keloid formation.

Effect of Human Wharton's Jelly Mesenchymal Stem Cell Paracrine Signaling on Keloid Fibroblasts

Keloid scars are abnormal benign fibroproliferative tumors with high recurrence rates and no current efficacious treatment. Accumulating evidence suggests that human umbilical cord Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) have antifibrotic properties. Paracrine signaling is considered one of the main underlying mechanisms behind the therapeutic effects of mesenchymal stem cells. However, the paracrine signaling effects of WJ-MSCs on keloids have not yet been reported. The aim of this study is to investigate paracrine signaling effects of human WJ-MSCs on keloid fibroblasts in vitro. Human umbilical cords and keloid skin samples were obtained, and WJ-MSCs and keloid fibroblasts were isolated and cultured. One-way and two-way paracrine culture systems between both cell types were investigated. Plasminogen activator inhibitor-I and transforming growth factor-β2 (TGF-β2) transcripts were upregulated in keloid fibroblasts cultured with WJ-MSC-conditioned medium (WJ-MSC-CM) and cocultured with inserts, while showing lower TGF-β3 gene expression. Interleukin (IL)-6, IL-8, TGF-β1, and TGF-β2 protein expression was also enhanced. The WJ-MSC-CM-treated keloid fibroblasts showed higher proliferation rates than their control keloid fibroblasts with no significant change in apoptosis rate or migration ability. In our culture conditions, the indirect application of WJ-MSCs on keloid fibroblasts may enhance their profibrotic phenotype.

Ultrasonographic and Magnetic Resonance Imaging Findings of Fibrous Pseudotumor of the Tunica Vaginalis: A Case Report

A fibrous pseudotumor is a benign fibroproliferative tumor arising from the paratesticular tissues. The majority of the reported cases show an involvement of the tunica vaginalis and the others are associated with the epididymis, spermatic cord and other surrounding connective tissues (1-3). To the best of our knowledge, there are only rarely reports on the experiences in diagnosing with both ultrasonography (US) and magnetic resonance imaging (MRI), even more rarely are reports on diagnosing with dynamic contrast-enhanced MRI. In this article, we present a case of fibrous pseudotumor of the tunica vaginalis presenting as painless palpable masses on the right scrotum in a 33-year-old man, with US and MRI findings including the dynamic study.

Case for diagnosis

Infantile digital fibromatosis or Reye's tumor is a benign fibroproliferative tumor, the etiopathogenesis of which has yet to be fully clarified. It typically presents at birth or in the first year of life and is characterized by a firm, flesh colored or erythematous nodule or nodules located on the digits. These lesions tend to regress spontaneously.

Fibromatosis stem cells rather than bone-marrow mesenchymal stem cells recapitulate a murine model of fibromatosis

Palmar fibromatosis is a benign fibroproliferative tumor of unknown etiology, with a high rate of recurrence after excision. The offending cells of palmar fibromatosis are myofibroblasts and the cellular origin of other myofibroblasts has previously been reported to be the bone marrow. However, further clarification of the relationship between bone marrow precursors and palmar fibromatosis is required. Stem cells (SCs) are known to exist in various tissues, but whether SCs can be isolated from fibromatosis tissue is still unclear. The purpose of this study was to isolate and identify stem cells from human palmar fibromatosis, and to evaluate the differences in the differentiation and fibrogenic capacities of bone marrow stem cells (BMSCs) and fibromatosis-derived stem cells (FSCs). We found that FSCs had better fibrogenic differentiation potential than BMSCs, whereas BMSCs had better adipogenic and chondrogenic differentiation capacities. Treatment with transforming growth factor-β1 increased the expression of α-smooth muscle actin, and types III and I collagen significantly more in FSCs than in BMSCs. An in vivo study further confirmed the results of fibrogenesis and suggested that FSCs can recapitulate the fibromatosis nodule. In summary, their myofibroblastic differentiation both in vivo and in vitro makes FSCs a potential cell source for future applications in murine models of fibromatosis or fibrogenesis.

Nodular Fasciitis of the Orbit: A Case Report and Brief Review of the Literature

Nodular fasciitis is a benign, reactive, fibroblastic proliferation in which nodules most commonly develop in the subcutaneous or superficial fascia of the extremities. The occurrence of these growths in the orbital region is relatively rare. Our intent is to report another orbital case of this benign fibroproliferative tumor and to provide a brief review of the pertinent medical literature. The salient pathologic features of nodular fasciitis are summarized. The potential for the misdiagnosis of these benign mesenchymal tumors as a malignant sarcomatous neoplasm is discussed. It is important for ophthalmologists to be aware of this pathologic entity and its pseudosarcomatous appearance.

Congenital infantile digital fibromatosis: a case report and review of the literature

Infantile digital fibromatosis (IDF) is a rare benign fibroproliferative tumor of early childhood. IDF preferentially affects the fingers and the toes. Malignant transformation or metastases have never been reported. Surgical treatment has been advocated previously but local recurrences were observed frequently. Recent literature supports clinical surveillance without any medical or surgical intervention as spontaneous regression usually occurs after two to three years. A six-month-old Caucasian girl with IDF on the left fourth digit is presented here. The tumor progressively increased in size after birth. Topical imiquimod cream and diflucortolone valerate cream, both displaying antifibrotic properties, had no effect on tumor growth. Currently the lesion size remains stable without any treatment. Early recognition of IDF is important in order to avoid unnecessary surgical intervention that may prove to be potentially aggravating, unless serious functional or cosmetic concerns intervene. Parents should be reassured concerning the benign nature of IDF and be informed that spontaneous involution of IDF might be expected.

Differential Gene Expression Analysis of Subcutaneous Fat, Fascia, and Skin Overlying a Dupuytren's Disease Nodule in Comparison to Control Tissue

Dupuytren's disease (DD) is a benign fibroproliferative tumor with an unknown etiology and high recurrence postsurgery. Several observations suggest the possible involvement of skin overlying nodule (SON) and the subcutaneous fat in the pathogenesis of DD. This study aims to (1) compare the gene expression levels of SON and subcutaneous fat in DD and normal subjects and (2) to compare transverse palmar fascia (Skoog's fibers) from DD patients as internal control tissue, with palmar fascia (transverse carpal ligament) from patients undergoing carpal tunnel release as external control. Skin, fat, and fascia were obtained from five DD patients of Caucasian origin (age = 66 +/- 14) and from five control subjects (age = 57 +/- 19) undergoing carpal tunnel release. Total ribonucleic acids was extracted from each sample and used for complementary deoxyribonucleic acid synthesis. Real-time quantitative polymerase chain reaction was used to assess the gene expression levels of six candidate genes: A disintegrin and metalloproteinase domain (ADAM12), aldehyde dehydrogenase 1 family member A1 (ALDH1A1), iroquois homeoboxprotein 6 (IRX6), periostin, osteoblast specific factor, proteoglycan 4, and tenascin C. Using independent t test, ADAM12, ALDH1A1, and IRX6 expression levels in DD fats were significantly (p < 0.05) higher than those in the controls. There is no significant difference in the gene expression levels of all six genes when comparing disease and control fascia and skin. Interestingly, ADAM12 up-regulation has also been observed in several other fibrotic and proliferative disorders. In conclusion, this study demonstrates potential roles for subcutaneous fat in DD pathogenesis as well as supports the use of transverse palmar fascia as appropriate control tissues in DD research.