Expression and function of SIRT6 in muscle invasive urothelial carcinoma of the bladder

SIRT6, a member of the class III histone deacetylase, has been shown to inhibit glycolysis and promote DNA double strand break repairs. Despite of its proposed tumor suppressor role, no significant differences in SIRT6 mRNA levels among normal bladder urothelium, non-muscle invasive, and muscle invasive urothelial carcinoma were noted in the two largest bladder cancer gene expression datasets available in Oncomine^TM. We therefore studied the expression and function of SIRT6 in muscle invasive urothelial carcinoma of the bladder. Immunohistochemistry studies of SIRT6 on radical cystectomy samples showed a dramatic decline of SIRT6 expression when bladder cancer progressed from T2 to T4. Functional study with bladder cancer cell lines confirmed its role in inhibiting glycolysis and cell proliferation. Reducing SIRT6 with siRNA, however, did not sensitize bladder cancer cells to drug induced DNA damage. The differential expression patterns of SIRT6 amongst different T stages of muscle invasive bladder cancers indicate less reliance on glycolysis when urothelial carcinoma invades deeper through the bladder and into the adjacent tissues.     

Photoexposition discriminates Notch 1 expression in human cutaneous squamous cell carcinoma.

The Notch signaling pathway may play opposing roles in cancer. It can be oncosuppressive or protumoral, depending on the cellular and tissue context. In skin cancer, Notch 1 expression is downregulated, thus supporting the hypothesis of an oncosuppressive role in cutaneous carcinomas. However, as members of the Notch family undergo downregulation upon exposure to UV irradiation, we wondered whether Notch 1 expression in skin carcinomas may be governed by additional factors, including UV exposure. We investigated the expression of Notch 1 and its ligands, Jagged 1, Jagged 2 and Delta-like 1, by immunohistochemistry in a series of premalignant and invasive cutaneous carcinomas, including 4 solar keratoses, 5 Bowen's disease, 5 squamous cell carcinomas on sun-exposed skin, 6 squamous cell carcinomas on sun-protected genital skin and 14 basal cell carcinomas of different histotypes (nodular, superficial type, sclerodermiform/infiltrating and baso-squamous). Expression of Notch 1 was decreased in solar keratoses and invasive squamous cell carcinomas localized on sun-exposed skin. In contrast, marked Notch 1 staining was observed in extragenital Bowen's disease as well as in genital (penile) human papilloma virus-related in situ and invasive squamous cell carcinomas. A diffuse Notch 1 staining was detected in nodular and superficial basal cell carcinomas while sclerodermiform/infiltrating and baso-squamous basal cell carcinomas showed a low to absent Notch 1 expression. Jagged 1, Jagged 2 and Delta-like 1 proteins were expressed in all tissues examined. Present findings show divergent expression of Notch 1 in skin cancer, depending on anatomical site and tumor histotype. Thus, whereas in UV-related squamous cell photocarcinogenesis Notch 1 downregulation could mirror a tumor suppressor function of the receptor, in sun-protected squamous cell carcinomas Notch 1 was upregulated. Furthermore, Notch 1 expression was minimal in basal cell carcinoma subtypes correlated with risk of recurrence (sclerodermiform/infiltrating and baso-squamous) in comparison with nodular and superficial types.     

Reciprocal correlation between the expression of cyclooxygenase-2 and E-cadherin in human bladder transitional cell carcinomas

Carcinoma cells become more motile and invasive via downmodulation of E-cadherin. Cyclooxygenase-2 (COX-2) expression is associated with tumor invasion and metastasis. The aim of this study is to investigate the relationship between the expression of COX-2 and E-cadherin in a bladder cancer cell line and human bladder transitional cell carcinoma (TCCs). Phorbol 12-myristate 13-acetate (PMA) treatment for 5637 bladder cancer cells increased COX-2 expression, slightly induced Slug expression, and decreased E-cadherin expression. Ectopic expression of COX-2 or prostaglandin E₂ (PGE₂) treatment for 5637 cells reduced E-cadherin expression. This finding was confirmed by the result that knockdown of COX-2 expression or indomethacin administration increased the expression of E-cadherin. When compared with cells’ motility in serum-free medium, the treatment of PMA and PGE₂ increased cell motility, and indomethacin treatment slightly decreased cell motility. In the tissues of bladder TCCs, COX-2 expression was inversely correlated with membranous E-cadherin expression and positively correlated with nuclear β-catenin expression. The expression of COX-2 and nuclear β-catenin expression was significantly higher in TCCs of high grade and invasive growth than in TCCs of low grade and noninvasive growth. In contrast, membranous E-cadherin expression was more decreased in tumors of high grade and invasive growth. In addition, nuclear β-catenin expression was significantly related to tumor recurrence. We suggest that COX-2 pathway reduces membranous E-cadherin expression in bladder TCCs and their expression pattern may provide important information in predicting the clinical behavior of bladder TCCs.     

Inhibition of γ-secretase by retinoic acid chalcone (RAC) induces G2/M arrest and triggers apoptosis in renal cell carcinoma

The present study was devised to investigate the effect of RAC on inhibition of cell proliferation and apoptosis of renal carcinoma cells. MTT assay and flow cytometry analysis were used to determine cell proliferation and apoptosis along with cell cycle examination. Western blot analysis and immunohistochemistry were used for the detection of expression levels of Notch1 and Jagged1 in renal cell carcinoma (RCC) and normal kidney tissues. The results revealed a significant inhibition of cell proliferation, G2/M phase cell cycle arrest and cell apoptosis at 30 μM concentration of RAC after 72 h. In ACHN and 769-P cells, the population in G2/M phase was increased to 45.27, and 54.23% respectively on treatment with 30 μM RAC for 72 h. In 769-P and ACHN renal carcinoma cells treatment with 30 μM RAC caused 69.71 and 59.27% of the cells to undergo apoptosis compared to 5.23 and 4.93% respectively in control cells. The positive staining rates of Notch1 and Jagged1 in renal carcinoma tissues were 95.3 and 93.0% compared to normal kidney tissues 36.4 and 42.4% respectively. Treatment of renal carcinoma tissues caused a significant decrease in staining rates of Notch1 and Jagged1 after 96 h. Thus RAC can be a potent agent in the treatment of renal cell carcinoma.     

Overexpression of COX2 indicates poor survival in urothelial bladder cancer

BackgroundCOX2 is a cyclo-oxygenase enzyme expressed in the tumor cells, inflammatory cells, stromal and non-epithelial cells. The study was conducted to evaluate the expression of COX2 in Urothelial carcinoma and find the association with progression and recurrence.MethodsThe expression of COX2 was evaluated by real-time PCR and immunohistochemistry.ResultsGene expression of COX2 was found to be upregulated >28-fold in urothelial cancer compared to adjacent normal bladder mucosa. Inflammatory cell expression of COX2 was found in 92% cases whereas only 37% cases showed COX2 overexpression in tumor cells. Tumor cell COX2 overexpression was significantly associated with invasion and recurrence.ConclusionCOX2 expression is a marker of invasion, recurrence and poor survival and may have a role in predicting the cases which will benefit from additional treatment with COX2 inhibitors in urothelial carcinoma.     

Notch1在前列腺癌细胞PC3中对其配体Jagged1表达的调控

目的探讨在前列腺癌细胞PC3中,Notch1和Jagged1对细胞生长的影响,及Notch1对其配体Jagged1表达的调控作用。方法通过siRNA干扰的方法分别抑制Notch1和Jagged1蛋白的表达,用MTT法检测PC3细胞的生长;分别通过siRNA干扰和转染质粒的方法,抑制和促进PC3细胞中Notch1蛋白的表达,用Western blot检测Jagged1蛋白水平,用Real-timePCR检测Jagged1 mRNA水平。结果抑制Notch1和Jagged1蛋白的表达后,PC3细胞的生长减慢;抑制Notch1的表达引起Jagged1的蛋白水平下降而过表达Notch1引起Jagged1的蛋白水平上升,同时,Jagged1蛋白水平与mRNA水平的变化不一致。结论Notch1和Jagged1对前列腺癌细胞PC3的生长有重要影响。Notch1可以调控其配体Jagged1的表达。     

膀胱尿路上皮癌中巨噬细胞移动抑制因子表达的临床意义

目的检测巨噬细胞移动抑制因子在膀胱尿路上皮癌中的表达及临床意义。方法采用Western bolt方法检测40对膀胱癌与手术切缘非癌组织中巨噬细胞移动抑制因子蛋白表达并分析其变化规律;再应用免疫组织化学法检测75对术后固定的膀胱癌与切缘组织中巨噬细胞移动抑制因子的表达并分析其与膀胱尿路上皮癌生物学行为的关系。结果膀胱尿路上皮癌中巨噬细胞移动抑制因子的表达与TNM分期呈正相关(P<0.05),并且在淋巴结转移阳性的膀胱尿路上皮癌中巨噬细胞移动抑制因子的表达显著高于淋巴结转移阴性患者,巨噬细胞移动抑制因子表达与膀胱尿路上皮癌患者生存期呈负相关(P=0.0341)。结论巨噬细胞移动抑制因子可能是膀胱尿路上皮癌变多阶段演进过程中的重要变化分子之一,可能成为膀胱尿路上皮癌分子诊断的生物标志。     

易混淆的膀胱活检小细胞性浸润性尿路上皮癌的诊断与鉴别诊断：附1例报告

目的：探讨膀胱活检中小细胞性浸润性尿路上皮癌的病理形态学特征以及与其它小细胞性病变的鉴别诊断。方法：对北京中医药大学东直门医院1例膀胱黏膜活检的病理及临床资料进行回顾性分析,并对相关国内外文献进行复习。结果：患者,男性,82岁,膀胱镜下见：在膀胱颈部10~12点可见黏膜突起如蕈状,蒂不明显。活检组织光镜下见：1)尿路上皮下小细胞肿瘤细胞呈弥漫性及巢状分布,间质增生;2)瘤细胞体积小,呈短梭形或淋巴细胞样,胞浆极少,局部瘤细胞胞浆宽广透明;3)核为圆形、椭圆形或梭形,核深染且结构不清,部分核不规则,可见双核、核重叠及多核瘤巨细胞,核仁不明显;4)未见核分裂象;5)局部组织可见挤压现象及局灶凝固性坏死;6)可见脉管浸润;7)局部异型增生的尿路上皮基底层处与固有膜内的小细胞性肿瘤成分有移行。免疫组织化学结果显示免疫表型CK少数细胞弱(+),其余标记均(?),病理诊断为：小细胞低分化癌。临床行经尿道膀胱肿瘤电切术,未送病理,数月后发现肠系膜多个转移瘤结节,瘤细胞形态与活检相似,局部瘤细胞核偏位,可见核仁及病理性核分裂象,免疫组化显示上皮性标记、p63及CD44V6均(+),神经内分泌标记(?),综合考虑最后病理诊断为：膀胱小细胞性浸润性尿路上皮癌伴肠壁转移。结论：膀胱小细胞性浸润性尿路上皮癌在膀胱镜活检标本中诊断难度较大,应重视其病理特点,鉴别诊断需结合临床和免疫组化特征综合评价,当二者不能提供有价值的帮助时,确诊还需以HE切片形态学特征为主,同时在报告中加以注明。膀胱镜活检标本病理诊断尿路上皮癌核分裂象应是有或无。     

Fascin stain as a potential marker of invasiveness in carcinomas of the urinary bladder: a retrospective study with biopsy and cytology correlation

The evaluation of invasion in urothelial carcinomas of the urinary bladder cannot be determined on cytology and can be particularly challenging in biopsy cases with limited sampling. Recent studies of bladder resection specimens suggest that fascin overexpression may be a marker of aggressive urothelial carcinomas and can help facilitate the assessment of invasion. In this study, we evaluated urine cytology and corresponding biopsy specimens with proven invasive urothelial carcinoma for fascin expression by immunohistochemistry. Thirty‐five patients diagnosed with positive urine cytology and biopsy‐proven invasive urothelial carcinoma between January 2003 and February 2009 were identified. We found increased fascin expression in 100% (35/35) of SurePathTM&!trade; urine cytology preparations as well as 100% (35/35) of corresponding biopsy cases with invasive urothelial carcinoma. On urine cytology, cytoplasmic fascin staining was moderate to intense in malignant tumor cell clusters and single cells and not observed in benign urothelial cells. Staining in biopsy cases was generally intense and cytoplasmic and present in both the invasive (100%) and noninvasive (31%) components of the lesion. These findings uphold the association of increased fascin expression in invasive urothelial carcinomas of the urinary bladder. We furthermore demonstrate that fascin staining can be performed successfully on SurePathTM&!trade; urine cytology preparations in which increased fascin expression correlates with invasion on biopsy. While not a definitive marker of invasion, as it is observed in in situ carcinoma, we conclude that the utilization of fascin immunohistochemistry on urine cytology might serve as a useful adjunct in predicting invasiveness in subsequent biopsies. Diagn. Cytopathol. 2010. © 2010 Wiley‐Liss, Inc.     

Measuring the dimension of invasive component in pT1 urothelial carcinoma in transurethral resection specimens can predict time to recurrence

Recurrences of nonmuscle-invasive urothelial bladder cancer are very common following resection. Predictive histopathologic variables in transurethral resection of bladder tumor (TURBT) specimens are of particular importance especially in determining the behavior of lamina propria-invasive tumors (high grade T1 stage). A total of 110 patients who underwent TURBT for urothelial carcinoma (1997-2005) from a single institution were retrospectively reviewed. Amount of tumor invasion by urothelial carcinoma was assessed in terms of percentage, focality (focal vs multifocal), and dimension (DI, aggregate length of invasion). Of 110 patients, 39 (35%) were found to have invasive high-grade urothelial carcinoma, including 9 females. Mean age was 70 years (range, 56-94 years). Twenty-three patients with high-grade T1 urothelial carcinoma had available follow-up information. Recurrence rate in these 23 patients was 96% (22/23). Nearly all of the recurences (221/22, 95%) occurred within 1 year of the initial TURBT. There was an inverse correlation of DI with time to recurrence (P < .05; correlation coefficient, −0.47). Urothelial carcinoma with a greater DI (>0.5 cm) had a mean time to recurrence of less than 6 months. Percentage of tumor invasion and focality was not associated with recurrence. The aggregate length of invasion may be a prognostic variable for high-risk nonmuscle-invasive bladder cancer. Measuring “aggregate length of invasive tumor,” if further validated in larger studies, could provide a practical alternative in substaging pT1 tumors in TURBT specimens.     

Cytokeratin 7 and cytokeratin 20 in primary urinary bladder carcinoma and matched lymph node metastasis.

BACKGROUND:-Cytokeratin 7 (CK7) and cytokeratin 20 (CK20) are 2 types of intermediate filament protein. Expression of CK7 is seen in the majority of primary urinary bladder carcinomas. CK20 is restricted to superficial and occasional intermediate cells of the normal urothelium of the bladder. Aberrant CK20 expression has been documented in urothelial carcinoma and has proved useful as an ancillary diagnostic aid for urinary bladder tumor. Our hypothesis is that the pattern of CK7 and CK20 expression in metastatic urothelial carcinoma duplicates the expression of the same markers in the primary tumors. Therefore, immunohistochemical staining of metastatic tumors for these 2 markers may be helpful for differential diagnosis in ambiguous metastatic tumor deposits. OBJECTIVE:-To determine the concordance of CK7 and CK20 expression in primary bladder urothelial carcinoma and the matched lymph node metastasis. DESIGN:-We studied 26 patients with lymph node metastases who underwent radical cystectomy and bilateral lymphadenectomy for bladder carcinoma. Immunohistochemical staining for CK7 and CK20 was performed on formalin-fixed paraffin-embedded tissues containing primary cancers and lymph node metastases. RESULTS:-In all cases, there was a concordant expression of CK20 in the primary cancer and its matched lymph node metastasis. Twelve cases (46%) showed positive CK20 immunoreactivity in the primary tumor and its matched lymph node metastases, whereas 14 cases (54%) were negative for CK20 in both the primary tumor and lymph node metastasis. All cases showed positive CK7 immunoreactivity in the primary cancers and matched lymph node metastases. CONCLUSIONS:-CK20 immunoreactivity is reliably observed in metastases from bladder cancer when the primary tumor expresses CK20.     

Plasmacytoid urothelial carcinoma of the urinary bladder: A case report and immunohistochemical study

We report a rare case of plasmacytoid urothelial carcinoma (PUC) of the urinary bladder. A 50-year-old man complained of pollakiuria and urinary incontinence. MRI detected a bladder tumor invading the rectum and bilateral hydroureteronephrosis. Radical cystectomy with partial resection of the rectum was performed, and ileus due to peritoneal dissemination occurred 2 years after surgery. He died of the disease 42 months after the initial presentation. Histologically, urothelial carcinoma in situ with a focal invasive urothelial carcinoma (IUC) component and widely spread PUC was observed. There was no lymph node metastasis. PUC cells had eccentrically placed nuclei and eosinophilic cytoplasm resembling plasmacytoma cells, and proliferated with a single-cell infiltrative pattern to the outside of the bladder. IUC cells with intracytoplasmic lumina were focally intermingled with PUC cells. Immunohistochemically, PUC cells were positive for cytokeratin 7, epithelial membrane antigen, and CA19-9, but negative for cytokeratin 20, E-cadherin, p63, and lymphoid markers. The Ki-67 labeling index of PUC cells was 9.3%. IUC containing intracytoplasmic lumina showed intermediate features of conventional IUC and PUC morphologically and immunohistochemically. PUC is a distinct entity of bladder cancer with a high propensity for invasion and poor prognosis.     

Ribonucleotide reductase M2 subunit is a novel diagnostic marker and a potential therapeutic target in bladder cancer

Morikawa T, Maeda D, Kume H, Homma Y & Fukayama M
(2010) Histopathology 57, 885–892 Ribonucleotide reductase M2 subunit is a novel diagnostic marker and a potential therapeutic target in bladder cancer Aims: To examine the immunohistochemical expression and function of ribonucleotide reductase M2 subunit (RRM2), a gemcitabine‐related molecule, in bladder cancer. Methods and results: One hundred and seventeen bladder specimens on a tissue microarray were immunostained for RRM2. Positive RRM2 staining was observed in none of 14 examples of non‐neoplastic urothelium, none of four low‐grade urothelial carcinoma (UC), 69 of 83 (83%) high‐grade UC, three of three (100%) squamous cell carcinoma and 12 of 13 (92%) lymph node metastasis of UC. RRM2 overexpression was associated significantly with muscularis propria invasion in UC patients who had undergone radical cystectomy (P = 0.005). Immunohistochemistry for RRM2 was then applied to small biopsy specimens of 15 cystitis with reactive atypia cases and 25 urothelial carcinoma in‐situ (CIS) cases. Positive RRM2 staining was found in one of 15 (6.7%) cystitis with reactive atypia cases and in 24 of 25 (96%) CIS cases. Finally, UM‐UC‐3 bladder cancer cells were transfected with RRM2 siRNAs and cell growth was evaluated. Knockdown of RRM2 protein markedly inhibited cell growth. Conclusions: We have shown frequent overexpression of RRM2 protein and its possible role in bladder cancer. Our results suggest that RRM2 is a novel diagnostic marker and a potential therapeutic target in bladder cancer.     

LncRNA,CRNDE promotes osteosarcoma cell proliferation,invasion and migration by regulating Notch1 signaling and epithelial-mesenchymal transition

Osteosarcoma is the most common bone malignancy in adolescence. Recently, the long non-coding RNAs (lncRNAs) were reported to play important roles in osteosarcoma progression. The present study examined the potential role of the lncRNA, Colorectal Neoplasia Differentially Expressed (CRNDE) and molecular mechanisms underlying osteosarcoma progression. In the present study, we identified that CRNDE was up-regulated in osteosarcoma tissues and cell lines, and CRNDE expression level was significantly higher in osteosarcoma tissues from patients with advanced stage and metastasis. Overexpression of CRNDE promoted cell growth, cell proliferation, cell invasion and migration, and increased cell population at S phase with a decreased cell population at G₀/G₁ phase in MG-63 cells. Knock-down of CRNDE suppressed cell growth, cell proliferation, cell invasion and migration, and decreased cell population at S phase with an increased cell population at G₀/G₁ phase in U2OS cells. Overexpression of CRNDE was found to enhance the activity of Notch1 signaling and promote epithelial-mesenchymal transition (EMT) in MG-63 cells, while knock-down of CRNDE exerted the opposite effects in U2OS cells. The in vivo results showed that knock-down of CRNDE suppressed the tumor growth in the nude mice inoculated with osteosarcoma cells, and knock-down of CRNDE also suppressed the mRNA expression of Notch1, JAG1, N-cadherin, vimentin, and increased the mRNA expression of E-cadherin in the tumor tissues. Collectively, our results indicated that CRNDE functioned as an oncogene in osteosarcoma cell lines, and CRNDE may exert its oncogenic role via regulating Notch1 signaling and EMT in osteosarcoma.     

Correlation of pathological grade and tumor stage of urothelial carcinomas with CD109 expression

Bladder cancer is one of the most common malignant diseases. Since a high-rate of recurrence is a serious problem for early stage urothelial carcinomas, new strategies for the management of recurrent urothelial carcinomas have been explored. CD109 is a glycosylphosphatidylinositol-anchored glycoprotein and is expressed in various cancer tissues, mainly squamous cell carcinomas. CD109 negatively controls transforming growth factor (TGF)-β/Smad signaling in vitro. In this study, we analyzed the clinical significance of CD109 expression in bladder cancer using immunohistochemistry. Of 156 urothelial carcinoma tissues, 69.9% were positive for CD109, whereas CD109 was not expressed in seven normal bladder epithelia. CD109 expression was significantly higher in non-muscle-invasive (pTa+pT1) or low-grade (G1+G2) tumors than in muscle-invasive (pT2-4) or high-grade (G3) tumors, and was associated with cancer-specific survival. Simultaneous immunostaining of CD109 and phosphorylated Smad2 showed an inverse immunoreactivity relationship between the two, suggesting that CD109 inhibits TGF-β/Smad signaling in tumor tissues. Interestingly, CD109 was found to be highly expressed in the basal layer of non-invasive urothelial carcinomas, and the expression pattern was similar to that of CD44, a marker of cancer stem cells. These findings suggest that CD109 is involved in bladder tumorigenesis and is a potential target for cancer immunotherapy.     

Notch3 and Jagged2 contribute to gastric cancer development and to glandular differentiation associated with MUC2 and MUC5AC expression

Kang H, An H‐J, Song J‐Y, Kim T‐H, Heo J‐H, Ahn D‐H & Kim G
(2012) Histopathology  61, 576–586 Notch3 and Jagged2 contribute to gastric cancer development and to glandular differentiation associated with MUC2 and MUC5AC expression Aims: Notch signalling plays diverse roles in malignant tumours as well as in normal tissue development. In this study we investigated the expression of Notch signalling pathway genes and their clinicopathological significance in gastric carcinomas. Methods and results: Notch1, Notch3, Jagged1, Jagged2 and Hes1 expression were analysed by quantitative real‐time polymerase chain reaction (qRT–PCR) (n = 81) and immunohistochemistry (n = 103) in gastric carcinomas. MUC2 and MUC5AC expression were also assessed, using immunohistochemistry only. With qRT–PCR, Notch1, Notch3, Jagged1 and Jagged2 expression were increased significantly in tumour compared to normal tissue (P < 0.001, P = 0.002, P = 0.008 and P < 0.001, respectively). Overexpression of Notch3 and Jagged2 was associated with intestinal‐type carcinomas (P = 0.024) and better histological differentiation (P = 0.047), respectively. Immunohistochemistry showed a reverse correlation between MUC2 and Notch3 or Jagged1 (P = 0.033 and P = 0.005, respectively) and between MUC5AC and Jagged1 or Hes1 (P = 0.004 and P = 0.002, respectively). Notch3 and Jagged2 gene overexpression related to a favourable outcome on univariate (P = 0.046 and P = 0.042, respectively) and multivariate (P = 0.045, Notch3) analysis. Conclusions: The expression of Notch3 and Jagged2 is associated not only with gastric cancer development but also with the intestinal/glandular differentiation of gastric carcinoma cells, suggesting a role as a possible favourable prognostic indicator.     

Prognostic significance of Notch signalling molecules and their involvement in the invasiveness of endometrial carcinoma cells

Mitsuhashi Y, Horiuchi A, Miyamoto T, Kashima H, Suzuki A & Shiozawa T
(2012) Histopathology  60, 826–837 Prognostic significance of Notch signalling molecules and their involvement in the invasiveness of endometrial carcinoma cells Aims: The aim of this study was to investigate the significance of the expression of Notch‐related molecules in endometrial carcinoma. Methods and results: The expression of Notch receptors (Notch1 and 3) and Notch ligands [Jagged (JAG) 1 and Delta‐like (DLL) 4] was examined immunohistochemically in 37 normal and 76 malignant endometrial tissue samples. For each section, immunohistochemical staining was scored using a positivity index (PI, full score; 200). The effects of a Notch inhibitor, DAPT, on cell proliferation, invasion and motility were investigated using endometrial carcinoma cell lines. The PIs for Notch1 (mean ± SD 90.4 ± 15.3), Notch3 (95.6 ± 20.4), JAG1 (95.5 ± 10.0) and DLL4 (88.2 ± 9.6), were significantly higher in endometrial carcinoma than normal endometrium. The PI for Notch1 was associated significantly with advanced International Federation of Gynecologists & Obstetricians (FIGO) stage. In addition, patients with tumours showing high expression of both Notch1 and JAG1 had a poor prognosis compared with those having double‐negative carcinomas (P = 0.015). DAPT suppressed invasiveness of cells derived from the endometrial carcinoma cell line KLE. Conclusions: The Notch1–JAG1 axis may enhance the invasive properties of endometrial carcinomas, which suggests the Notch pathway may be a promising target for the treatment of this malignancy.