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Background@#Cholecystitis is an important risk factor for gallbladder cancer, but the bile microbiome and its association with gallbladder disease has not been investigated fully.We aimed to analyze the bile microbiome in normal conditions, chronic cholecystitis, and gallbladder cancer, and to identify candidate bacteria that play an important role in gallbladder carcinogenesis. @*Methods@#We performed metagenome sequencing on bile samples of 10 healthy individuals, 10 patients with chronic cholecystitis, and 5 patients with gallbladder cancer, and compared the clinical, radiological, and pathological characteristics of the participants. @*Results@#No significant bacterial signal was identified in the normal bile. The predominant dysbiotic bacteria in both chronic cholecystitis and gallbladder cancer were those belonging to the Enterobacteriaceae family. Klebsiella increased significantly in the order of normal, chronic cholecystitis, and gallbladder cancer. Patients with chronic cholecystitis and dysbiotic microbiome patterns had larger gallstones and showed marked epithelial atypia, which are considered as precancerous conditions. @*Conclusion@#We investigated the bile microbiome in normal, chronic cholecystitis, and gallbladder cancer. We suggest possible roles of Enterobacteriaceae, including Klebsiella, in gallbladder carcinogenesis. Our findings reveal a possible link between a dysbiotic bile microbiome and the development of chronic calculous cholecystitis and gallbladder cancer.
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Background@#Cholecystitis is an important risk factor for gallbladder cancer, but the bile microbiome and its association with gallbladder disease has not been investigated fully.We aimed to analyze the bile microbiome in normal conditions, chronic cholecystitis, and gallbladder cancer, and to identify candidate bacteria that play an important role in gallbladder carcinogenesis. @*Methods@#We performed metagenome sequencing on bile samples of 10 healthy individuals, 10 patients with chronic cholecystitis, and 5 patients with gallbladder cancer, and compared the clinical, radiological, and pathological characteristics of the participants. @*Results@#No significant bacterial signal was identified in the normal bile. The predominant dysbiotic bacteria in both chronic cholecystitis and gallbladder cancer were those belonging to the Enterobacteriaceae family. Klebsiella increased significantly in the order of normal, chronic cholecystitis, and gallbladder cancer. Patients with chronic cholecystitis and dysbiotic microbiome patterns had larger gallstones and showed marked epithelial atypia, which are considered as precancerous conditions. @*Conclusion@#We investigated the bile microbiome in normal, chronic cholecystitis, and gallbladder cancer. We suggest possible roles of Enterobacteriaceae, including Klebsiella, in gallbladder carcinogenesis. Our findings reveal a possible link between a dysbiotic bile microbiome and the development of chronic calculous cholecystitis and gallbladder cancer.
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Purpose@#Mesenchymal epithelial transition (MET) is a proto-oncogene that encodes a heterodimerictransmembrane receptor tyrosine kinase for the hepatocyte growth factor. Aberrant METsignaling has been described in several solid tumors—especially non-small cell lung cancer—and is associated with tumor progression and adverse prognosis. As MET is a potentialtherapeutic target, information regarding its prevalence and clinicopathological relevanceis crucial. @*Materials and Methods@#We investigated MET expression and gene amplification in 113 gallbladder cancers usingtissue microarray. Immunohistochemistry was used to evaluate MET overexpression, andsilver/fluorescence in situ hybridization (ISH) was used to assess gene copy number. @*Results@#MET overexpression was found in 37 cases of gallbladder carcinoma (39.8%), and geneamplification was present in 17 cases (18.3%). MET protein expression did not correlatewith MET amplification. MET amplification was significantly associated with aggressive clinicopathologicalfeatures, including high histological grade, advanced pT category, lymphnode metastasis, and advanced American Joint Committee on Cancer stage. There was nosignificant correlation between any clinicopathological factors and MET overexpression. Nodifference in survival was found with respect to MET overexpression and amplification status. @*Conclusion@#Our data suggested that MET might be a potential therapeutic target for targeted therapyin gallbladder cancer, because MET amplification was found in a subset of tumors associatedwith adverse prognostic factors. Detection of MET amplification by ISH might be a usefulpredictive biomarker test for anti-MET therapy.
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BACKGROUND: The heterogeneity of histological findings in preclinical diet-induced nonalcoholic fatty liver disease (NAFLD) animal models is highly challenging. Here, we aimed to evaluate the feasibility and stability of repeated liver biopsy in NAFLD animal models. METHODS: Heterogeneity of diet-induced NAFLD was evaluated at different time points in 52 high-fat diet (HFD), 35 methionine choline-deficiency diet (MCD), and 166 western diet (WD) induced NAFLD mice. Serial liver biopsies (left lateral, right medial, and left medial lobes) were performed monthly for up to 3 months. Mortality rates and changes in food intake, body weight, and liver enzymes were assessed. RESULTS: At 12 weeks, of the HFD animals, 14% and 30% did not develop steatosis and lobular inflammation, respectively; of the MCD animals, 7% did not develop lobular inflammation; and of the WD animals, 14% and 51% did not develop steatosis and lobular inflammation, respectively. The mortality rate of repeated liver biopsy was 1.62% (2/123 mice died). Repeated liver biopsy can be used to trace disease progression. Although body weight, food intake, and liver enzymes slightly changed after biopsy, all recovered within a week. Repeated liver biopsy did not affect the degrees of inflammation and steatosis of the other liver lobes. CONCLUSION: The diet-induced NAFLD models were quite heterogeneous. Our results suggest that the repeated liver biopsy before treatment was applicable and stable in this NAFLD animal study.
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Animaux , Souris , Biopsie , Poids , Régime alimentaire , Alimentation riche en graisse , Régime occidental , Évolution de la maladie , Consommation alimentaire , Inflammation , Foie , Méthionine , Modèles animaux , Mortalité , Stéatose hépatique non alcoolique , Caractéristiques de la populationRÉSUMÉ
BACKGROUND/AIMS: For the clinical application of stem cell therapy, functional enhancement is needed to increase the survival rate and the engraftment rate. The purpose of this study was to investigate functional enhancement of the paracrine effect using stem cells and hepatocyte-like cells and to minimize stem cell homing by using a scaffold system in a liver disease model. METHODS: A microporator was used to overexpress Foxa2 in adipose tissue-derived stem cells (ADSCs), which were cultured in a poly(lactic-co-glycolic acid) (PLGA) scaffold. Later, the ADSCs were cultured in hepatic differentiation medium for 2 weeks by a 3-step method. For in vivo experiments, Foxa2-overexpressing ADSCs were loaded in the scaffold, cultured in hepatic differentiation medium and later were implanted in the dorsa of nude mice subjected to acute liver injury (thioacetamide intraperitoneal injection). RESULTS: Foxa2-overexpressing ADSCs showed greater increases in hepatocyte-specific gene markers (alpha fetoprotein [AFP], cytokeratin 18 [CK18], and albumin), cytoplasmic glycogen storage, and cytochrome P450 expression than cells that underwent the conventional differentiation method. In vivo experiments using the nude mouse model showed that 2 weeks after scaffold implantation, the mRNA expression of AFP, CK18, dipeptidyl peptidase 4 (CD26), and connexin 32 (CX32) was higher in the Foxa2-overexpressing ADSCs group than in the ADSCs group. The Foxa2-overexpressing ADSCs scaffold treatment group showed attenuated liver injury without stem cell homing in the thioacetamide-induced acute liver injury model. CONCLUSIONS: Foxa2-overexpressing ADSCs applied in a scaffold system enhanced hepatocyte-like differentiation and attenuated acute liver damage in an acute liver injury model without homing effects.
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Animaux , Souris , Cytochrome P-450 enzyme system , Cytoplasme , Dipeptidyl peptidase 4 , Protéines foetales , Glycogène , Kératine-18 , Maladies du foie , Défaillance hépatique aigüe , Foie , Cellules souches mésenchymateuses , Méthodes , Souris nude , ARN messager , Cellules souches , Taux de survieRÉSUMÉ
BACKGROUND: Lung cancer is the most common cause of cancer-related death, and adenocarcinoma is the most common histologic subtype. MicroRNA is a small non-coding RNA that inhibits multiple target gene expression at the post-transcriptional level and is commonly dysregulated in malignant tumors. The purpose of this study was to analyze the expression of microRNA-374a (miR-374a) in lung adenocarcinoma and correlate its expression with various clinicopathological characteristics.METHODS: The expression level of miR-374a was measured in 111 formalin-fixed paraffin-embedded lung adenocarcinoma tissues using reverse transcription-quantitative polymerase chain reaction assays. The correlation between miR-374a expression and clinicopathological parameters, including clinical outcome, was further analyzed.RESULTS: High miR-374 expression was correlated with advanced pT category (chi-square test, p=.004) and pleural invasion (chi-square test, p=.034). Survival analysis revealed that patients with high miR-374a expression had significantly shorter disease-free survival relative to those with low miR-374a expression (log-rank test, p=.032).CONCLUSIONS: miR-374a expression may serve as a potential prognostic biomarker for predicting recurrence in early stage lung adenocarcinoma after curative surgery.
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Humains , Adénocarcinome , Survie sans rechute , Expression des gènes , Tumeurs du poumon , Poumon , microARN , Réaction de polymérisation en chaîne , Récidive , Petit ARN non traduitRÉSUMÉ
BACKGROUND/AIMS@#Intestinal cholesterol absorption includes intestinal Niemann-Pick C1-like 1 (NPC1L1) and is an important target pathway in nonalcoholic fatty liver disease (NAFLD). We investigated the expression of NPC1L1 and its correlation with liver X receptor (LXR) expression in peripheral mononuclear (PMN) cells in patients with NAFLD.@*METHODS@#We evaluated intestinal expression of NPC1L1 in 25 NAFLD patients and 28 healthy controls. We calculated the mRNA expression levels of LXR and farnesoid X receptor (FXR), which are master players of cholesterol metabolism in PMN cells. The protein expression of ABCA1, ABCG5/8, NPC1L1, SREBP, LXR, FXR, and CD36 was measured on tissue samples from the duodenum and ileum.@*RESULTS@#The expression of LXR (p = 0.01) and FXR (p = 0.03) in PMN cells was increased in the NAFLD group compared to the control group. Duodenal NPC1L1 decreased in the NAFLD group compared to the healthy controls (3.38 ± 1.4 vs. 2.42 ± 1.2, p = 0.05). NPC1L1 expression in the duodenum was negatively correlated with LXR expression in PMN cells. Expression of LXR and FXR in the ileum was also negatively correlated with the expression of LXR in PMN cells.@*CONCLUSIONS@#Duodenal NPC1L1 expression was decreased in NAFLD and was negatively correlated with LXR expression in PMN cells.
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Sjögren's syndrome (SS) is a chronic inflammatory autoimmune disorder that affects mainly salivary and lacrimal glands, but its cause remains largely unknown. Clinical data indicating that SS occurs in a substantial proportion of patients with lupus points to common pathogenic mechanisms underlying the two diseases. To address this idea, we asked whether SS develops in the lupus-prone mouse strain sanroque (SAN). Owing to hyper-activation of follicular helper T (Tfh) cells, female SAN mice developed lupus-like symptoms at approximately 20 wk of age but there were no signs of SS at that time. However, symptoms typical of SS were evident at approximately 40 wk of age, as judged by reduced saliva flow rate, sialadenitis, and IgG deposits in the salivary glands. Increases in serum titers of SS-related autoantibodies and numbers of autoantibody-secreting cells in cervical lymph nodes (LNs) preceded the pathologic manifestations of SS and were accompanied by expansion of Tfh cells and their downstream effector cells. Thus, our results suggest that chronic dysregulation of Tfh cells in salivary gland-draining LNs is sufficient to drive the development of SS in lupus-prone mice.
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Animaux , Femelle , Humains , Souris , Autoanticorps , Auto-immunité , Modèles animaux de maladie humaine , Immunoglobuline G , Appareil lacrymal , Lupus érythémateux disséminé , Noeuds lymphatiques , Salive , Glandes salivaires , SialadéniteRÉSUMÉ
Sjögren's syndrome (SS) is a chronic heterogeneous disease that mainly affects exocrine glands, leading to sicca syndromes such as xerostomia. Despite the second highest prevalence rate among systemic autoimmune diseases, its pathophysiology remains largely unknown. Here we report that SKG mice, a cardinal model of Th17 cell-mediated arthritis, also develop a secondary form of SS-like disorder upon systemic exposure to purified curdlan, a type of β-glucan. The reduced production of saliva was not caused by focal immune cell infiltrates but was associated with IgG deposits in salivary glands. Sera from curdlan-injected SKG mice contained elevated titers of IgG (predominantly IgG1), autoantibody to the muscarinic type 3 receptor (M3R) and inhibited carbachol-induced Ca2+ signaling in salivary acinar cells. These results suggest that the Th17 cells that are elicited in SKG mice promote the production of salivary gland-specific autoantibodies including anti-M3R IgG; the antibodies are then deposited on acinar cells and inhibit M3R-mediated signaling required for salivation, finally leading to hypofunction of the salivary glands. This type II hypersensitivity reaction may explain the origin of secondary SS occurring without focal leukocyte infiltrates.
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Animaux , Souris , Cellules acineuses , Anticorps , Arthrite , Autoanticorps , Maladies auto-immunes , Glandes exocrines , Hypersensibilité , Immunoglobuline G , Leucocytes , Prévalence , Salive , Glandes salivaires , Salivation , Syndrome de Gougerot-Sjögren , Cellules Th17 , XérostomieRÉSUMÉ
The intracellular parasite Toxoplasma gondii has unique dense granule antigens (GRAs) that are crucial for host infection. Emerging evidence suggests that GRA8 of T. gondii is a promising serodiagnostic marker in toxoplasmosis. However, little is known about the intracellular regulatory mechanisms involved in GRA8-induced host responses. We found that GRA8 interacts with host proteins involved in mitochondria activation and might be useful as a therapeutic strategy for sepsis. Here, we show that protein kinase-Cα (PKCα)-mediated phosphorylation of T. gondii GRA8 (Thr220) is required for mitochondrial trafficking and regulates the interaction of C terminal of GRA8 with nucleotide binding domain of ATP5A1. Furthermore, GRA8 interacts with SIRT3 in mitochondria, facilitating ATP5A1 deacetylation (K506 and K531), adenosine triphosphate production and subsequent anti-septic activity in vivo. Taken together, these results demonstrate a new anti-sepsis therapeutic strategy using T. gondii GRA8-induced mitochondrial metabolic resuscitation. This strategy represents an urgently needed paradigm shift for therapeutic intervention.
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BACKGROUND: Smad4 and PTEN are prognostic indicators for various tumor types. Smad4 regulates tumor suppression, whereas PTEN inhibits cell proliferation. We analyzed and compared the performance of Smad4 and PTEN for predicting the prognosis of patients with colorectal adenocarcinoma. METHODS: Combined expression patterns based on Smad4+/– and PTEN+/– status were evaluated by immunostaining using a tissue microarray of colorectal adenocarcinoma. The relationships between the protein expression and clinicopathological variables were analyzed. RESULTS: Smad4–/PTEN– status was most frequently observed in metastatic adenocarcinoma, followed by primary adenocarcinoma and tubular adenoma (p<.001). When Smad4–/PTEN– and Smad4+/PTEN+ groups were compared, Smad4–/PTEN– status was associated with high N stage (p=.018) and defective mismatch repair proteins (p=.006). Significant differences in diseasefree survival and overall survival were observed among the three groups (Smad4+/PTEN+, Smad4–/PTEN+ or Smad4+/PTEN–, and Smad4–/PTEN–) (all p<.05). CONCLUSIONS: Concurrent loss of Smad4 and PTEN may lead to more aggressive disease and poor prognosis in patients with colorectal adenocarcinoma compared to the loss of Smad4 or PTEN alone.
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Humains , Adénocarcinome , Adénomes , Prolifération cellulaire , Tumeurs du côlon , Réparation de mésappariement de l'ADN , PronosticRÉSUMÉ
BACKGROUND: BRCA1-associated protein 1 (BAP1) mutations are frequently reported in clear cell renal cell carcinoma (ccRCC); however, very few studies have evaluated the role of these mutations in other renal cell carcinoma (RCC) subtypes. Therefore, we analyzed BAP1 protein expression using immunohistochemistry in several RCC subtypes and assessed its relationship with clinicopathological characteristics of patients. METHODS: BAP1 expression was immunohistochemically evaluated in tissue microarray blocks constructed from 371 samples of RCC collected from two medical institutions. BAP1 expression was evaluated based on the extent of nuclear staining in tumor cells, and no expression or expression in < 10% of tumor cells was defined as negative. RESULTS: Loss of BAP1 expression was observed in ccRCC (56/300, 18.7%), chromophobe RCC (6/26, 23.1%), and clear cell papillary RCC (1/4, 25%), while we failed to detect BAP1 expression loss in papillary RCC, acquired cystic disease-associated RCC, or collecting duct carcinoma. In ccRCC, loss of BAP1 expression was significantly associated with high World Health Organization (WHO)/International Society of Urological Pathology (ISUP) grade (p = .002); however, no significant correlation was observed between loss of BAP1 expression and survival in ccRCC. Loss of BAP1 expression showed no association with prognostic factors in chromophobe RCC. CONCLUSIONS: Loss of BAP1 nuclear expression was observed in both ccRCC and chromophobe RCC. In addition, BAP1 expression loss was associated with poor prognostic factors such as high WHO/ISUP grade in ccRCC.
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Humains , Néphrocarcinome , Immunohistochimie , Anatomopathologie , Organisation mondiale de la santéRÉSUMÉ
PURPOSE: Wnt7a is a glycoprotein involved in embryonic development and the progression of different types of malignant tumors. This study aimed to detect the level of Wnt7a expression in breast cancer and explore its role in the disease progression and prognosis. METHODS: A total of 258 patients diagnosed with invasive ductal carcinoma of the breast were included in this study. Using tissue microarray and immunohistochemical staining, we evaluated the association between Wnt7a expression and clinicopathological parameters, and the prognostic value of Wnt7a. RESULTS: Wnt7a expression was significantly correlated with estrogen receptor (ER) expression (odds ratio, 3.95; 95% confidence interval [CI], 1.99–7.80; p < 0.001). On univariate and multivariate analyses, loss of Wnt7a expression was associated with poor disease-free survival (DFS) (multivariate hazard ratio [HR], 9.12; 95% CI, 1.80–46.09; p=0.008), but not with poor overall survival (OS). In the ER-positive group (n=114), loss of Wnt7a expression was an independent prognostic factor for shorter DFS (multivariate HR, 13.54; 95% CI, 1.11–165.73; p=0.042) and OS (multivariate HR, 4.76; 95% CI, 1.29–17.61; p=0.019) on univariate and multivariate analyses. However, in the ER-negative group, there was no significant difference in DFS and OS according to Wnt7a expression. CONCLUSION: The loss of Wnt7a expression might be a meaningful factor in assessing DFS and OS, especially in ER-positive breast cancer.
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Femelle , Humains , Grossesse , Tumeurs du sein , Région mammaire , Carcinome canalaire , Évolution de la maladie , Survie sans rechute , Développement embryonnaire , Oestrogènes , Glycoprotéines , Analyse multifactorielle , Pronostic , Récepteurs des oestrogènes , Protéines de type WinglessRÉSUMÉ
PURPOSE: Previous studies have shown the role of Sal-like protein 4 (SALL4) as a biomarker in hepatocellular carcinoma (HCC), and some studies have shown the relationship between SALL4 and prognosis. Given the debates in study groups differences in terms of etiologic causes between Western and Asian HCC and detection methods, we attempted to verify the features of SALL4 immunoreactivity and its clinical correlation in Korean HCC patients. METHODS: Immunohistochemical staining of SALL4 of tissue microarrays (TMAs) consisting of 213 surgically resected HCC patients' tissue were scored in a semiquantitative scoring system with immunoreactive score and the results analyzed with clinical outcome, in addition to general demographics and clinical characteristics. RESULTS: SALL4 immunoreactivity was expressed in 50 cases. Relevance between SALL4 and α-FP correlated significantly (P = 0.002). Also, the SALL4-positive patients had considerably higher tumor grade (P < 0.001). The survival analysis showed negative correlation with SALL4 immunoreactivity in all HCC patient groups, but SALL4 immunoreactivity in T3 and T4 HCC correlated with poor prognosis. CONCLUSION: Here, we found that positive immunostaining of SALL4 is correlated with poor patient survival outcome in large and undifferentiated Korean HCC. SALL4 expression showed close relationship with clinical outcomes of HCCs in Korean patients.
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Humains , Asiatiques , Carcinome hépatocellulaire , Démographie , Immunohistochimie , Analyse sur microréseau , PronosticRÉSUMÉ
PURPOSE: Previous studies have shown the role of Sal-like protein 4 (SALL4) as a biomarker in hepatocellular carcinoma (HCC), and some studies have shown the relationship between SALL4 and prognosis. Given the debates in study groups differences in terms of etiologic causes between Western and Asian HCC and detection methods, we attempted to verify the features of SALL4 immunoreactivity and its clinical correlation in Korean HCC patients. METHODS: Immunohistochemical staining of SALL4 of tissue microarrays (TMAs) consisting of 213 surgically resected HCC patients' tissue were scored in a semiquantitative scoring system with immunoreactive score and the results analyzed with clinical outcome, in addition to general demographics and clinical characteristics. RESULTS: SALL4 immunoreactivity was expressed in 50 cases. Relevance between SALL4 and α-FP correlated significantly (P = 0.002). Also, the SALL4-positive patients had considerably higher tumor grade (P < 0.001). The survival analysis showed negative correlation with SALL4 immunoreactivity in all HCC patient groups, but SALL4 immunoreactivity in T3 and T4 HCC correlated with poor prognosis. CONCLUSION: Here, we found that positive immunostaining of SALL4 is correlated with poor patient survival outcome in large and undifferentiated Korean HCC. SALL4 expression showed close relationship with clinical outcomes of HCCs in Korean patients.
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Humains , Asiatiques , Carcinome hépatocellulaire , Démographie , Immunohistochimie , Analyse sur microréseau , PronosticRÉSUMÉ
Diabetic nephropathy is a chronic microvascular complication of type 2 diabetes and the leading cause of end-stage renal disease. We report the case of a 34-year-old male, newly diagnosed with type 2 diabetes mellitus, who had advanced-stage nephropathy with glomerular crescents. A moderately-to-severely decreased glomerular filtration rate with nephrotic syndrome was seen at the time of diagnosis of diabetes. Proliferative diabetic retinopathy was detected, but there was no positive finding in serology tests for glomerulonephritis. Non-necrotizing cellular crescents and nodular glomerulosclerosis were observed in a kidney biopsy, and renal function declined rapidly to the end stage. We review data on diabetic glomerulosclerosis with cellular crescents and the rapid progression of nephropathy.
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Adulte , Humains , Mâle , Biopsie , Diabète de type 2 , Néphropathies diabétiques , Rétinopathie diabétique , Diagnostic , Évolution de la maladie , Débit de filtration glomérulaire , Glomérulonéphrite , Rein , Défaillance rénale chronique , Syndrome néphrotique , AnatomopathologieRÉSUMÉ
Fox transcription factors play a critical role in the regulation of a variety of biological processes. While FoxM1 behaves like the oncogenic transcription factor, FoxO3a is known as a tumor suppressor by inhibiting FoxM1. This study aimed to investigate the clinicopathological significance of FoxM1 and FoxO3a expression in breast cancer. Expression of FoxM1 and FoxO3a were analyzed by immunohistochemical staining on tissue microarray sections from 236 breast cancer patients, and correlated with various clinicopathological characteristics. Overexpression of FoxM1 correlated with adverse clinicopathological features, such as larger tumor size, lymph node metastasis, advanced tumor stage, and lymphovascular invasion. The Kaplan-Meier survival curves revealed no prognostic significance of FoxM1 expression. However, in subgroup analyses with patients of estrogen receptor (ER) positive breast cancers, FoxM1 overexpression associated with poor disease free and overall survival. No association was found between FoxO3a and FoxM1 expression. Regarding clinicopathological variables, the only association between histologic grade and FoxO3a was observed. In conclusion, FoxM1 overexpression was significantly associated with aggressive phenotypes and poor prognosis of ER-positive breast cancer. These findings suggest the possible role of FoxM1 as a prognostic biomarker and putative target of anti-cancer therapy.
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Femelle , Humains , Tumeurs du sein/composition chimique , Facteurs de transcription Forkhead/analyse , Phénotype , Pronostic , Récepteur ErbB-2/analyse , Récepteurs des oestrogènes/analyseRÉSUMÉ
PURPOSE: Dual-specificity protein phosphatase 4 (DUSP4), also known as mitogen-activated protein kinase phosphatase (MKP) 2 is a member of the inducible nuclear MKP group. The role of DUSP4 in cancer development and progression appears to vary with the type of malignancy. The purpose of this study was to investigate DUSP4 expression in a case series of invasive ductal carcinoma of the breast. METHODS: We constructed tissue microarrays consisting of 16, 14, 47, and 266 cases of normal breast tissue, usual ductal hyperplasia, ductal carcinoma in situ, and invasive ductal carcinoma, respectively. DUSP4 expression was investigated by immunohistochemistry. RESULTS: Cytoplasmic DUSP4 expression was observed. DUSP4 was more frequently expressed in malignant than in benign cases (p=0.024). The mean DUSP4 expression score was significantly higher in malignant tumors than in benign lesions (p=0.019). DUSP4 expression was significantly correlated with a larger tumor size (>2 cm, p=0.015). There was no significant correlation between overall survival or disease-free survival and DUSP4 expression in all 266 patients. We evaluated the impact of DUSP4 expression on the survival of 120 patients with T1-stage tumors. Interestingly, Kaplan-Meier survival curves revealed that DUSP4 expression had a significant effect on both overall patient survival (p=0.034, log-rank test) and disease-free survival (p=0.045, log-rank test). In early T-stage breast cancer, DUSP4 expression was associated with a worse prognosis. CONCLUSION: DUSP4 is frequently upregulated in breast malignancy, and may play an important role in cancer development and progression. In addition, it may be a marker of adverse prognosis, especially in patients with early T1-stage cancer.