BACKGROUND: Because keratoacanthoma (KA) and squamous cell carcinoma (SCC) are very similar with respect to clinical and histological features but are different with respect to prognosis and treatment, it is necessary to differentiate these two diseases. A number of recent studies have been attempted to differentiate these two diseases using immunohistochemical stains; however, the results obtained using these approaches were inconsistent. OBJECTIVE: The purpose of this study was to examine the expression pattern of polyclonal antibody to lysyl oxidase (LOX) on KA and SCC using an immunohistochemical staining method, and to evaluate the ability of this method in distinguishing these two diseases. METHODS: The expression of LOX in 10 cases of KA and 10 cases of SCC, which were confirmed by histopathologic examination, and 10 cases of normal human skin as a control, were evaluated using an immunohistochemical staining method. We divided the degree of immunohistochemical staining into three classifications --high density, low density, and no density-- based on the level of the expression of LOX in the epidermis and the tumor. Evaluation of the immunohistochemical staining was performed by two dermatologists and one pathologist. RESULTS: The rates of high, low, and no density in KA were 50%, 50%, and 0%, respectively. The rates of high, low, and no density in SCC were 40%, 10%, and 50%, respectively. The rates of high, low, and no density in the control group were 70%, 30%, and 0%, respectively. CONCLUSION: Because the degree of LOX expression in KA and SCC was very diverse, it could not be reliably used as a differential stain for the two diseases. But interestingly, no LOX expression was observed in SCC. This suggests that if expression of LOX is absent, there is a high probability of being diagnosed with a malignant skin tumor rather than a benign skin tumor.
Carcinoma, Squamous Cell ; Diagnosis, Differential ; Epidermis ; Humans ; Keratoacanthoma ; Prognosis ; Protein-Lysine 6-Oxidase ; Skin

BACKGROUND: Intratumoral fibrosis (ITF) is a frequent histologic finding in solid organ tumors. Renal cell carcinoma (RCC) is a highly vascularized tumor with different shapes and degrees of ITF and inflammation. ITF is a poor prognostic factor, especially in breast cancer, and is related to intratumoral necrosis (ITN) and intratumoral inflammation (ITI). However, the significance of ITF in RCC has not been fully studied. In this study, we evaluate the relationships between ITF and other clinicopathologic parameters associated with RCC prognosis. METHODS: ITF was evaluated in 204 clear cell renal cell carcinoma (CCRCC) specimens according to presence and grade of fibrosis, degree of ITI, and presence of ITN. Lysyl oxidase (LOX) expression in tumor cells was also evaluated with clinicopathologic parameters. RESULTS: Among 204 CCRCC cases, 167 (81.7%) showed ITF, 71 (34.8%) showed ITI, 35 (17.2%) showed ITN, and 111 (54.4%) showed LOX expression. ITF correlated with Fuhrman nuclear grade (p = .046), lymphovascular invasion (LVI) (p = .027), and ITN (p = .036). Patients with ITF had a poor five-year overall survival rate (p = .104). CONCLUSIONS: ITF is related to other poor prognostic factors in CCRCC, such as Fuhrman nuclear grade, ITN, and LVI, but ITF itself had no significant correlation with prognosis of CCRCC.
Breast Neoplasms ; Carcinoma, Renal Cell ; Fibrosis ; Humans ; Inflammation ; Necrosis ; Prognosis ; Protein-Lysine 6-Oxidase ; Survival Rate

PURPOSE: Lysyl oxidase (LOX) controls the cross-linking and maturation of elastin and collagen fibers. In this study, we investigated the association between LOX gene polymorphisms and intracranial aneurysm (IA) formation in a homogeneous Korean population. MATERIALS AND METHODS: This cross-sectional study involved 80 age-sex matched patients with IA and controls. Fisher's exact test was performed to analyze allelic associations between ten single nucleotide polymorphisms (SNPs) and IA, including 41 ruptured and 39 unruptured cases. Haplotype-specific associations were analyzed using the omnibus test estimating asymptotic chi-square statistics. RESULTS: Of ten SNPs, three SNPs (rs2303656, rs3900446, and rs763497) were significantly associated with IA (p<0.01). The C allele of rs3900446 was significantly related to increased IA risk with a significant threshold [odds ratio (OR)=20.15, p=4.8×10⁻⁵]. Meanwhile, the A allele of rs2303656 showed a preventive effect against IA formation (p=8.2×10⁻⁴). Seventeen of 247 haplotype structures showed a suggestive association with IA (asymptotic p<0.001). Of ten SNP haplotype combinations, the CG combination of rs3900446 and rs763497 reached Bonferroni-adjusted significant threshold in IA patients (minor haplotype frequency=0.113, asymptotic p=1.3×10⁻⁵). However, there was no association between aneurysm rupture and the LOX gene. CONCLUSION: This preliminary study indicated that LOX gene polymorphisms, such as rs2303656, rs3900446, and rs763497, may play crucial roles in IA formation in the Korean population. Our novel findings need to be validated in a large-scale independent population.
Alleles ; Aneurysm ; Collagen ; Cross-Sectional Studies ; Elastin ; Haplotypes ; Humans ; Intracranial Aneurysm* ; Polymorphism, Single Nucleotide ; Protein-Lysine 6-Oxidase* ; Rupture ; Subarachnoid Hemorrhage

Tissue injury provokes a series of events containing inflammation, new tissue formation and tissue remodeling which are regulated by the spatially and temporally coordinated organization. It is an evolutionarily conserved, multi-cellular, multi-molecular process via complex signalling network. Tissue injury disorders present grievous clinical prob-lems and are likely to increase since they are generally associated with the prevailing diseases such as diabetes, hyper-tension and obesity. Although these dynamic responses vary not only for the different types of trauma but also for the different organs, a balancing act between the tissue degradation and tissue synthesis is the same. In this process, the degradation of old extracellular matrix (ECM) elements and new ones' synthesis and deposition play an essential role, especially collagens. Lysyl oxidase (LOX) and four lysyl oxidase-like proteins are a group of enzymes capable of catalyzing cross-linking reaction of collagen and elastin, thus initiating the formation of covalent cross-links that insolubilize ECM proteins. In this way, LOX facilitates ECM stabilization through ECM formation, development, maturation and remodeling. This ability determines its potential role in tissue repair and regeneration. In this review, based on the current in vitro, animal and human in vivo studies which have shown the significant role of the LOXs in tissue repair, e.g., tendon regeneration, ligament healing, cutaneous wound healing, and cartilage remodeling, we focused on the role of the LOXs in inflammation phase, proliferation phase, and tissue remodeling phase of the repair process. By summarizing its healing role, we hope to shed light on the understanding of its potential in tissue repair and provide up to date therapeutic strategies towards related injuries.
Animals ; Cartilage ; Collagen ; Elastin ; Extracellular Matrix ; Hope ; Humans ; In Vitro Techniques ; Inflammation ; Ligaments ; Obesity ; Oxidoreductases* ; Protein-Lysine 6-Oxidase ; Regeneration ; Tendons ; Wound Healing

OBJECTIVETo explore the mechanism of serotonin-promoted osteoblast differentiation.

METHODSExpression levels of collagen I and lysyl oxidase (LOX) in osteoblast were measured by RT-PCR after treated by (50, 100, 200 and 400 ng/L) serotonin. LOX siRNA effect was measured by Western blot, and protein levels of collagen I were determined by ELISA after treated by serotonin. Expression levels of Smad2 and Smad3 in osteoblasts were also measured by RT-PCR after treated by serotonin.Moreover, expression levels of LOX were measured by RT-PCR after Smad3 was knockout.

RESULTSSerotonin promoted collagen I and LOX expression. The expression level of collagen I was significantly decreased by LOX siRNA. Furthermore, serotonin up-regulated the expression of Smad2 and Smad3 in osteoblasts, and the expression level of LOX was inhibited by Smad3 siRNA.

CONCLUSIONSerotonin promoted collagen I expression by activating Smads signaling pathway and up-regulating the LOX expression.

Blotting, Western ; Cell Differentiation ; Cells, Cultured ; Collagen Type I ; metabolism ; Humans ; Osteoblasts ; drug effects ; metabolism ; Protein-Lysine 6-Oxidase ; metabolism ; RNA, Small Interfering ; Serotonin ; pharmacology ; Signal Transduction ; Smad2 Protein ; metabolism ; Smad3 Protein ; metabolism ; Up-Regulation

The progress of research on the the anterior cruciate ligament (ACL) wound healing demonstrates that the synovial tissue in the knee joint plays a very important role in the healing process of injured ACL. Therefore, the molecular response mechanisms of lysyl oxidase (LOX) and matrix metalloproteina (MMP) in normal/injured ACL fibroblast cells could be considered to perform the major analysis function of injured ACL healing mechanism. The mRNA expressions of LOXs and MMPs and the activity expressions of MMP-2 in ACL fibroblasts co-cultured with synovial cells were analyzed by quantitative real-time PCR and zymography. The results showed that co-culture could regulate the mRNA expressions of LOXs and MMPs in the ACL fibroblasts cells. These results suggest that the differential expressions of LOXs and MMP-1, 2, 3 in co-cultured ACL indicate that interaction crosstalk do exist between ACL cells and synovial cells and provide a theoretical basis for subsequent exploration of the mechanisms and treatment of ACL injury and repair.
Anterior Cruciate Ligament ; cytology ; Anterior Cruciate Ligament Injuries ; Coculture Techniques ; Fibroblasts ; cytology ; metabolism ; Humans ; Knee Injuries ; physiopathology ; Knee Joint ; cytology ; Matrix Metalloproteinases ; genetics ; metabolism ; Protein-Lysine 6-Oxidase ; genetics ; metabolism ; Synovial Membrane ; cytology ; Wound Healing ; physiology

Cells consistently face stressful conditions, which cause them to modulate a variety of intracellular processes and adapt to these environmental changes via regulation of gene expression. Hyperosmotic and oxidative stresses are significant stressors that induce cellular damage, and finally cell death. In this study, oligonucleotide microarrays were employed to investigate mRNA level changes in cells exposed to hyperosmotic or oxidative conditions. In addition, since heat shock protein 70 (HSP70) is one of the most inducible stress proteins and plays pivotal role to protect cells against stressful condition, we performed microarray analysis in HSP70 overexpressing cells to identify the genes expressed in a HSP70 dependent manner. Under hyperosmotic or oxidative stress conditions, a variety of genes showed altered expression. Down regulation of protein phosphatase1 beta (PP1 beta) and sphingosine 1 phosphate phosphatase 1 (SPPase1) was detected in both stress conditions. Microarray analysis of HSP70 overexpressing cells demonstrated that diverse mRNA species depend on the level of cellular HSP70. Genes encoding lysyl oxidase, thrombospondin 1, and procollagen displayed altered expression in all tested conditions. The results of this study will be useful to construct networks of stress response genes.
Cell Death ; Down-Regulation ; Gene Expression Regulation ; Gene Expression* ; Heat-Shock Proteins ; HSP70 Heat-Shock Proteins ; Microarray Analysis ; Oligonucleotide Array Sequence Analysis ; Oxidative Stress* ; Procollagen ; Protein-Lysine 6-Oxidase ; RNA, Messenger ; Sphingosine ; Thrombospondin 1

OBJECTIVETo study the effects of lysyl oxidase (LOX) on the migration and adhesion of the human gastric cancer cell line HGC-27 cells in vitro.

METHODSThe human gastric cancer cell line HGC-27 cells were cultured in vitro, and treated with different concentration of β-aminopropionitrile (BAPN). The ability of migration was assessed by wound-healing assay. The ability of adhesion was detected by homogenous and heterogeneous adhesion experiments.

RESULTSCompared that with 0 mmol/L BAPN, the ability of migration of the cells after treatment with 0.2 mmol/L BAPN was descended at 8, 24, 32 and 48 h; the number of cells with homogeneous adhesion was increased from (6.97 ± 0.07) × 10(3)/ml to (7.78 ± 0.11) × 10(3)/ml; and the number of cells with heterogeneous adhesion was decreased from (8.98 ± 0.15) × 10(3)/ml to (8.35 ± 0.10) × 10(3)/ml, both < 0.05. Compared with that of cells treated with 0 mmol/L and 0.2 mmol/L BAPN, the migration ability of cells after treatment with 0.3 mmol/L BAPN was descended at 8, 24, 32 and 48 h; the number of cells with homogeneous adhesion was raised to (8.02 ± 0.11) × 10(3)/ml and the number of cells with heterogeneous adhesion was down to (7.93 ± 0.07) × 10(3)/ml (P < 0.05).

CONCLUSIONLOX may promote the metastasis of cancer cells by enhancing invasion, increasing heterogeneous adhesion and decreasing homogeneous adhesion.

Aminopropionitrile ; administration & dosage ; pharmacology ; Cell Adhesion ; drug effects ; Cell Line, Tumor ; Cell Movement ; drug effects ; Dose-Response Relationship, Drug ; Humans ; Neoplasm Invasiveness ; Protein-Lysine 6-Oxidase ; antagonists & inhibitors ; metabolism ; physiology ; Stomach Neoplasms ; enzymology ; pathology

OBJECTIVETo compare the expressions of lysyl oxidase (LOX) and matrix metalloproteinases-2 (MMP-2) in gastric cancer and pericancerous tissues, in gastric cancers with and without lymph node metastasis, and to analyze the effects of LOX and MMP-2 on tumor invasion and metastasis.

METHODSGastric cancer and pericancerous tissues were collected from 46 patients who underwent surgery. Levels of LOX and MMP-2 mRNA were detected by RT-PCR. Protein abundance of LOX and MMP-2 was examined using Western blot.

RESULTSExpressions of LOX and MMP-2 mRNA, and protein in 46 gastric cancers were significantly higher than that in 46 pericancerous tissues. In gastric cancer with lymph node metastasis, the levels of LOX and MMP-2 mRNA and protein were higher than those in gastric cancers without lymph node metastasis (P < 0.05). In the groups of gastric cancer with lymph node metastasis, expression of LOX was positively correlated with MMP-2 protein expression (P < 0.01).

CONCLUSIONSExpressions of LOX and MMP-2 in gastric cancer tissues are significantly higher than that in pericancerous tissues. The expressions of LOX and MMP-2 in gastric cancer with lymph node metastasis are higher than that in gastric cancer without lymph node metastasis. Expressions of LOX and MMP-2 are positively correlated. The results suggest that LOX and MMP-2 may promote the growth and metastasis of gastric cancer.

Adenocarcinoma ; metabolism ; pathology ; surgery ; Biomarkers, Tumor ; metabolism ; Female ; Gastrectomy ; Humans ; Lymphatic Metastasis ; Male ; Matrix Metalloproteinase 2 ; genetics ; metabolism ; Middle Aged ; Neoplasm Invasiveness ; Protein-Lysine 6-Oxidase ; genetics ; metabolism ; RNA, Messenger ; metabolism ; Stomach ; metabolism ; surgery ; Stomach Neoplasms ; metabolism ; pathology ; surgery

Carcinoma-associated fibroblasts (CAFs) are the main cellular components of the tumor microenvironment and promote cancer progression by modifying the extracellular matrix (ECM). The tumor-associated ECM is characterized by collagen crosslinking catalyzed by lysyl oxidase (LOX). Small extracellular vesicles (sEVs) mediate cell-cell communication. However, the interactions between sEVs and the ECM remain unclear. Here, we demonstrated that sEVs released from oral squamous cell carcinoma (OSCC)-derived CAFs induce collagen crosslinking, thereby promoting epithelial-mesenchymal transition (EMT). CAF sEVs preferably bound to the ECM rather than being taken up by fibroblasts and induced collagen crosslinking, and a LOX inhibitor or blocking antibody suppressed this effect. Active LOX (αLOX), but not the LOX precursor, was enriched in CAF sEVs and interacted with periostin, fibronectin, and bone morphogenetic protein-1 on the surface of sEVs. CAF sEV-associated integrin α2β1 mediated the binding of CAF sEVs to collagen I, and blocking integrin α2β1 inhibited collagen crosslinking by interfering with CAF sEV binding to collagen I. CAF sEV-induced collagen crosslinking promoted the EMT of OSCC through FAK/paxillin/YAP pathway. Taken together, these findings reveal a novel role of CAF sEVs in tumor ECM remodeling, suggesting a critical mechanism for CAF-induced EMT of cancer cells.
Humans ; Paxillin/metabolism* ; Protein-Lysine 6-Oxidase/metabolism* ; Carcinoma, Squamous Cell/pathology* ; Epithelial-Mesenchymal Transition ; Integrin alpha2beta1/metabolism* ; Mouth Neoplasms/pathology* ; Collagen/metabolism* ; Fibroblasts ; Extracellular Vesicles/metabolism* ; Cell Line, Tumor ; Tumor Microenvironment