Discovering cancer stem-like molecule, nuclear factor I X, using spatial transcriptome in gastric cancer.

Gastric cancer (GC) is characterized by significant intratumoral heterogeneity, and stem cells are promising therapeutic targets. Despite advancements in spatial transcriptome analyses, unexplored targets for addressing cancer stemness remain unknown. This study aimed to identify Nuclear Factor IX (NFIX) as a critical regulator of cancer stemness in GC and evaluate its clinicopathological significance and function. Spatial transcriptome analysis of GC was conducted. The correlation between NFIX expression, clinicopathological factors, and prognosis was assessed using immunostaining in 127 GC cases. Functional analyses of cancer cell lines validated these findings. Spatial transcriptome analysis stratified GC tissues based on genetic profiles, identified CSC-like cells, and further refined the classification to identify and highlight the significance of NFIX, as validated by Monocle 3 and CytoTRACE analyses. Knockdown experiments in cancer cell lines have demonstrated the involvement of NFIX in cancer cell proliferation and kinase activity. This study underscores the role of spatial transcriptome analysis in refining GC tissue classification and identifying therapeutic targets, highlighting NFIX as a pivotal factor. NFIX expression is correlated with poor prognosis and drives GC progression, suggesting its potential as a novel therapeutic target for personalized GC therapies.

MCM4 expression is associated with high-grade histology, tumor progression and poor prognosis in urothelial carcinoma.

BACKGROUND: We previously reported Minichromosome maintenance 4 (MCM4) overexpression in gastric cancer. However, the clinicopathological significance of MCM4 in urothelial carcinoma (UC) has not been investigated. To clarify the clinicopathological significance of MCM4 in UC, we investigated MCM4 expression with immunohistochemistry (IHC). METHODS: We analyzed the expression and distribution of MCM4 in 124 upper tract urothelial carcinoma (UTUC) samples by IHC. Additionally, using 108 urine samples, we analyzed MCM4 Immunocytochemistry (ICC) expression in urine cytology. RESULTS: In normal urothelium, MCM4 expression was weak or absent. Meanwhile, the strong nuclear expression of MCM4 was observed in UTUC tissues, and it was detected in 77 (62%) of a total of 124 UTUC cases. MCM4-positive UTUC cases were associated with nodular/flat morphology, high grade, high T stage, and poor prognosis. Moreover, MCM4 expression was significantly higher in the invasive front than in the tumor surface. Similar results were also obtained in TCGA bladder cancer cohort. Additionally, MCM4 expression was associated with high expression of Ki-67, HER2, EGFR, and p53 in UTUC. Among representative cancer-related molecules, MCM4 had an independent predictive value for progression-free survival and high-grade UC. ICC for MCM4 was also performed on urine cytology slides and showed that the nuclear expression of MCM4 was more frequently found in UC cells than in non-neoplastic cells. The diagnostic accuracy of urine cytology was improved by combining MCM4 immunostaining with cytology. CONCLUSION: These results suggest that MCM4 might be a useful predictive biomarker for high-grade histology, tumor progression and poor prognosis in UC. Moreover, ICC for MCM4 might be helpful for UC detection as additional markers in the cytomorphology-based diagnosis.

Clinicopathological significance of TUBB3 in upper tract urothelial carcinoma and possible application in urine cytology.

ßIII-Tubulin, encoded by the TUBB3 gene, is a microtubule protein. We previously reported that TUBB3 is overexpressed in renal cell carcinoma. We investigated the clinicopathological significance of TUBB3 in upper tract urothelial carcinoma (UTUC) by immunohistochemistry. In normal tissue, TUBB3 expression was weak or absent. In contrast, TUBB3 overexpression was observed in urothelial carcinoma (UC) tissues in 51 (49%) of 103 UTUC cases. TUBB3 overexpression was associated with nodular/flat morphology, high-grade disease, high T stage, and a poor prognosis. Similar results were obtained in The Cancer Genome Atlas bladder cancer cohort. TUBB3 expression was also associated with high Ki-67 labeling index, CD44v9, HER2, EGFR, and p53 expression in UTUC. Among representative cancer-related molecules, TUBB3 was an independent predictor of progression-free survival and high-grade UC. Finally, using urine cytology samples, we analyzed TUBB3 expression by immunocytochemistry. TUBB3 expression was more frequently found in UC cells than in nonneoplastic cells. The diagnostic accuracy of urine cytology was improved when combined with TUBB3 immunostaining. The findings suggest the importance of TUBB3 in tumor progression and its potential application as a biomarker for high-grade disease and the prognosis of UC. Moreover, combination with TUBB3 immunostaining might improve the diagnostic accuracy of urine cytology.

Dual immunocytochemical staining of annexin A10 and p53 in low-grade and papillary urothelial carcinoma contributes to improvement of diagnostic accuracy in urine cytology.

BACKGROUND: Urothelial carcinoma (UC) is a common type of human cancer and, although urine cytology is a useful method for identifying high-grade UC (HGUC), its ability to diagnose low-grade UC (LGUC) is limited. The authors previously reported that annexin A10 (ANXA10) expression was strongly linked to both papillary and early stage LGUC and was inversely correlated with p53 expression in upper tract UC (UTUC) and bladder UC. However, it remains largely unknown whether ANXA10 is useful as a diagnostic marker for urine cytology. METHODS: In this study, the authors used 104 biopsy and 314 urine cytology samples to investigate the efficacy of ANXA10 and p53 expression by immunohistochemistry and immunocytochemistry. RESULTS: In immunohistochemistry analysis, expression levels of ANXA10 and p53 were either weak or absent in noncancerous tissues, whereas ANXA10 overexpression was observed patients with LGUC, and strong expression of p53 was identified in patients with HGUC. In immunocytochemistry analysis, sensitivity was not good for the detection of UC, especially UTUC, by cytology alone, but it was improved by combining cytology with ANXA10 and p53 to detect both bladder UC and UTUC. Receiver operating characteristic curve analysis also confirmed the diagnostic superiority of cytology combining ANXA10 and p53 for the detection of all UCs, including both HGUC and LGUC (area under the curve, 0.84). CONCLUSIONS: To the authors' knowledge, this is the first report that the combination of ANXA10 and p53 has potential application as a diagnostic immunomarker for improving the diagnostic accuracy of urine cytology.

A Case of Bilateral Synchronous Paratesticular Leiomyoma.

Bilateral synchronous paratesticular leiomyoma (BSPL) is a rare tumor that originates from smooth muscle cells in the paratesticular region. Four BSPL cases have been reported sporadically, starting with the 1991 report by Aus and Boiesen. Herein, we report the case of a 60-year-old male with a bilateral scrotal mass with a maximum size of 7.5 cm. Histological examination revealed oval to spindle-shaped tumor cells with a fascicular growth pattern. Immunohistochemically, the tumor cells were positive for α-smooth muscle actin. The pathological diagnosis was a leiomyoma. Based on the simultaneous bilateral nature of the disease, BSPL was diagnosed. In conclusion, we encountered a rare case of BSPL, and our report may contribute to the understanding of this disease.

Spatial PD-L1, immune-cell microenvironment, and genomic copy-number alteration patterns and drivers of invasive-disease transition in prospective oral precancer cohort.

BACKGROUND: Studies of the immune landscape led to breakthrough trials of programmed death-1 (PD-1) inhibitors for recurrent/metastatic head and neck squamous cell carcinoma therapy. This study investigated the timing, influence of somatic copy-number alterations (SCNAs), and clinical implications of PD-L1 and immune-cell patterns in oral precancer (OPC). METHODS: The authors evaluated spatial CD3, CD3/8, and CD68 density (cells/mm2 ) and PD-L1 (membranous expression in cytokeratin-positive intraepithelial neoplastic cells and CD68) patterns by multiplex immunofluorescence in a 188-patient prospective OPC cohort, characterized by clinical, histologic, and SCNA risk factors and protocol-specified primary end point of invasive cancer. The authors used Wilcoxon rank-sum and Fisher exact tests, linear mixed effect models, mediation, and Cox regression and recursive-partitioning analyses. RESULTS: Epithelial, but not CD68 immune-cell, PD-L1 expression was detected in 28% of OPCs, correlated with immune-cell infiltration, 9p21.3 loss of heterozygosity (LOH), and inferior oral cancer-free survival (OCFS), notably in OPCs with low CD3/8 cell density, dysplasia, and/or 9p21.3 LOH. High CD3/8 cell density in dysplastic lesions predicted better OCFS and eliminated the excess risk associated with prior oral cancer and dysplasia. PD-L1 and CD3/8 patterns revealed inferior OCFS in PD-L1 high intrinsic induction and dysplastic immune-cold subgroups. CONCLUSION: This report provides spatial insight into the immune landscape and drivers of OPCs, and a publicly available immunogenomic data set for future precancer interrogation. The data suggest that 9p21.3 LOH triggers an immune-hot inflammatory phenotype; whereas increased 9p deletion size encompassing CD274 at 9p24.1 may contribute to CD3/8 and PD-L1 depletion during invasive transition. The inferior OCFS in PD-L1-high, immune-cold OPCs support the development of T-cell recruitment strategies.

Minichromosome Maintenance 4 Is Associated with Cancer Stemness and Poor Survival of Patients with Gastric Cancer.

INTRODUCTION: Gastric cancer (GC) is a leading cause of cancer-related death worldwide. This study focused on minichromosome maintenance 4 (MCM4), a DNA helicase component that functions in DNA replication. Using spheroid colony formation, having a colony rich in cancer stem cells, this study aimed to investigate the clinicopathological importance of MCM4. METHODS: We examined MCM4 expression using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) analysis in 10 and 113 GC cases, respectively. MCM4 function in GC was also investigated by RNA interference in GC cell lines. RESULTS: In qRT-PCR and IHC analysis, high MCM4 expression was found in 60% and 83% of GC cases, respectively. MCM4-positive GC cases were significantly associated with higher T grade and tumor stage. Additionally, high MCM4 expression was significantly associated with poor prognosis and was an independent prognostic factor in multivariate analysis. MCM4 was significantly coexpressed with CD133, matrix metalloproteinase 7 (MMP7), epidermal growth factor (EGFR), and mesenchymal-epithelial transition factor (cMET). In GC cell lines, MCM4 knockdown affected cell growth and protein kinase B (Akt), extracellular signal-regulated kinase (ERK), and EGFR pathways. CONCLUSION: These results indicate that MCM4 expression could be a key regulator in GC progression and is pivotal in treating GC.

ANXA10 Expression Is Inversely Associated with Tumor Stage, Grade, and TP53 Expression in Upper and Lower Urothelial Carcinoma.

INTRODUCTION: Urothelial carcinoma (UC) is a common type of malignant disease, but little is known about the diagnostic and prognostic markers of upper urinary tract urothelial cancer (UTUC) because of its rarity. To clarify the significance of ANXA10 in UTUC, we studied ANXA10 expression with immunohistochemistry (IHC). METHODS: The expression of ANXA10 was analyzed in the upper and lower urinary tract of UC by IHC in combination with The Cancer Genome Atlas (TCGA) data analysis. The association between ANXA10 expression and representative cancer-related molecules was also evaluated. RESULTS: ANXA10 expression was weak in normal upper tract urothelium but was positive in 39/117 (33%) UTUCs. ANXA10 was more frequently positive in tumors with pure UC (36%, p < 0.05), papillary morphology (50%, p < 0.01), low grade (G1/2: 57%, p < 0.01), and pTa/is/1 stage (55%, p < 0.01) than in those with histological variants (0%), nodular morphology (9%), G3 (16%), and pT2/3/4 (13%), respectively. ANXA10-positive patients showed better cancer-specific survival and progression-free survival than ANXA10-negative patients (p < 0.05). IHC showed that ANXA10 positivity was detected more in cases with the low expression of TP53 (p < 0.01) and Ki-67 labeling index <20% (p < 0.01). In TCGA dataset of muscle-invasive bladder cancer, higher ANXA10 expression correlated with papillary morphology, lower grade/stage, luminal papillary subtype, wild-type TP53, and FGFR3 gene mutation. CONCLUSION: We revealed that ANXA10 expression was increased during carcinogenesis and was observed more frequently in papillary UC of lower grade and stage. However, its expression decreased as cancer progressed. Therefore, the ANXA10 expression in UTUC might be clinically useful for decision-making.

Clinicopathological significance of the overexpression of MUC1 in upper tract urothelial carcinoma and possible application as a diagnostic marker.

Mucin 1 (MUC1) overexpression has been reported in many malignancies and is associated with a poor prognosis. However, the clinicopathological significance of MUC1 in upper tract urothelial carcinoma (UTUC) has not been investigated. We analyzed the expression and distribution of MUC1 in UTUC by immunohistochemistry. In normal urothelium, MUC1 expression was observed on the surface of umbrella cells. Meanwhile, the strong expression of MUC1 was observed in cell membranes and cytoplasm in UTUC tissues, and it was detected in 64 (58%) of a total of 110 UTUC cases. MUC1-positive UTUC cases were associated with nodular/flat morphology, high grade, high T stage, and lymphatic and venous invasion and poor prognosis. Additionally, MUC1 expression was associated with high expression of Ki-67, programmed death-ligand 1 (PD-L1), CD44 variant 9 (CD44v9), human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR), and p53 in UTUC. Furthermore, immunocytochemistry for MUC1 on urine cytology slides demonstrated that the strong staining of MUC1 was more frequently found in tumor cells than in nonneoplastic cells. The diagnostic accuracy of urine cytology was improved by combining MUC1 immunostaining with cytology. These results suggest that MUC1 may be a prognostic biomarker in UTUC, and MUC1 exression has a potential application as a diagnostic immunomarker for urine cytology.

Diminished Immune Surveillance during Histologic Progression of Intraductal Papillary Mucinous Neoplasms Offers a Therapeutic Opportunity for Cancer Interception.

PURPOSE: Intraductal papillary mucinous neoplasms (IPMN) are bona fide precursors to pancreatic ductal adenocarcinoma (PDAC). While genomic alterations during multistep IPMN progression have been well cataloged, the accompanying changes within the tumor immune microenvironment (TIME) have not been comprehensively studied. Herein, we investigated TIME-related alterations during IPMN progression, using multiplex immunofluorescence (mIF) coupled with high-resolution image analyses. EXPERIMENTAL DESIGN: Two sets of formalin-fixed, paraffin-embedded tissue samples from surgically resected IPMNs were analyzed. The training set of 30 samples consisted of 11 low-grade IPMN (LG-IPMN), 17 high-grade IPMN (HG-IPMN), and 2 IPMN with PDAC, while a validation set of 93 samples comprised of 55 LG-IPMN and 38 HG-IPMN. The training set was analyzed with two panels of immuno-oncology-related biomarkers, while the validation set was analyzed with a subset of markers found significantly altered in the training set. RESULTS: Cell types indicative of enhanced immune surveillance, including cytotoxic and memory T cells, and antigen-experienced T cells and B cells, were all found at higher densities within isolated LG-IPMNs compared with HG-IPMNs. Notably, the TIME of LG-IPMNs that had progressed at the time of surgical resection (progressor LGD) resembled that of the synchronous HG-IPMNs, underscoring that attenuated immune surveillance occurs even in LG-IPMNs destined for progression. CONCLUSIONS: Our findings provide a basis for interception of cystic neoplasia to PDAC, through maintenance of sustained immune surveillance using vaccines and other prevention approaches.

Cytological and histological findings of upper tract mucinous urothelial carcinoma with clear cell component: A case report and review of literature.

Mucinous urothelial carcinoma (UC) is a rare variant and only 18 cases of mucinous UC have been reported. In this article, we report a case of mucinous UC focusing on both cytological and histological findings. A 92-year-old female was referred to our hospital because of gross hematuria. Clinical computed tomography scan showed 2.2-cm papillary lesion in the lower part of the left ureter. Urine cytology was performed, and cytopathological findings showed that there were a few atypical cells with pale to clear cytoplasm, and a low amount of mucin in the background was identified by periodic acid-schiff (PAS) and alcian blue (AB) staining. Laparoscopic radical nephrectomy of left renal pelvis and ureter was performed. The gross examination revealed that a white-gray, papillary-sessile tumor was found in the lower part of the left ureter. Histologically, conventional high grade UC cells were seen in some areas, and tumor cells in other areas showed abundant clear cytoplasm with extracellular and intracytoplasmic mucin. Immunohistochemical analysis revealed that tumor cells were positive for CK7, CK20, p63, GATA3, MUC1, MUC2, and MUC5AC and negative for MUC6 and CDX2. Histopathological diagnosis was mucinous UC with clear cell component, and the pathological stage was pT1N0M0. The patient has remained well and disease-free for 3 months after the operation. Familiarity and recognizing the characteristic pathological findings of mucinous UC are important because it represents a malignant neoplasm.

Clinicopathological significance of claspin overexpression and its efficacy as a novel biomarker for the diagnosis of urothelial carcinoma.

We previously reported that claspin is a key regulator in the progression of gastric cancer and renal cell carcinoma. However, the clinicopathological significance of claspin in urothelial carcinoma (UC) has not been investigated. We analyzed the expression and distribution of claspin in UC cases by immunohistochemistry. In the non-neoplastic urothelium, the expression of claspin was either weak or absent, whereas UC tissues showed nuclear staining. The expression of claspin was detected in 58 (42%) of a total of 138 upper tract UC cases treated by radical nephroureterectomy without neoadjuvant chemotherapy. Claspin-positive UC cases were associated with nodular/flat morphology, variant histology, high tumor grade, high pathological T grade, and lymphatic and venous invasion. The expression of claspin was significantly associated with decreased progression-free survival and cancer-specific survival. In addition, claspin was co-expressed with Ki-67, PD-L1, HER2, EGFR, and p53 in consecutive tumor sections of UC. An immunohistochemical analysis of claspin in biopsy specimens revealed that strong to moderate claspin staining was more frequently observed in carcinoma in situ in comparison to dysplasia or the benign urothelium. Furthermore, immunocytochemistry for claspin on urine cytology slides demonstrated that the proportion of claspin-positive cells was significantly greater in high-grade UC than in benign cases. These results suggest that claspin may be a novel prognostic marker and a possible therapeutic target molecule for UC. Moreover, claspin could be a useful diagnostic biomarker of urothelial neoplasia.

Automated 3D scoring of fluorescence in situ hybridization (FISH) using a confocal whole slide imaging scanner.

Fluorescence in situ hybridization (FISH) is a technique to visualize specific DNA/RNA sequences within the cell nuclei and provide the presence, location and structural integrity of genes on chromosomes. A confocal Whole Slide Imaging (WSI) scanner technology has superior depth resolution compared to wide-field fluorescence imaging. Confocal WSI has the ability to perform serial optical sections with specimen imaging, which is critical for 3D tissue reconstruction for volumetric spatial analysis. The standard clinical manual scoring for FISH is labor-intensive, time-consuming and subjective. Application of multi-gene FISH analysis alongside 3D imaging, significantly increase the level of complexity required for an accurate 3D analysis. Therefore, the purpose of this study is to establish automated 3D FISH scoring for z-stack images from confocal WSI scanner. The algorithm and the application we developed, SHIMARIS PAFQ, successfully employs 3D calculations for clear individual cell nuclei segmentation, gene signals detection and distribution of break-apart probes signal patterns, including standard break-apart, and variant patterns due to truncation, and deletion, etc. The analysis was accurate and precise when compared with ground truth clinical manual counting and scoring reported in ten lymphoma and solid tumors cases. The algorithm and the application we developed, SHIMARIS PAFQ, is objective and more efficient than the conventional procedure. It enables the automated counting of more nuclei, precisely detecting additional abnormal signal variations in nuclei patterns and analyzes gigabyte multi-layer stacking imaging data of tissue samples from patients. Currently, we are developing a deep learning algorithm for automated tumor area detection to be integrated with SHIMARIS PAFQ.

SPC18 Expression Is an Independent Prognostic Indicator of Patients with Esophageal Squamous Cell Carcinoma.

OBJECTIVES: Esophageal cancer is the sixth most common malignancy worldwide. Signal peptidase complex 18 (SPC18) protein, which is encoded by the SEC11A gene, is one of the subunits of the signal peptidase complex and plays an important role in the secretion of proteins including transforming growth factor α (TGF-α). In this study, we investigated the significance of SPC18 expression in human esophageal squamous cell carcinoma (ESCC). METHODS: SPC18 expression was examined by immunohistochemistry. RNA interference was used to inhibit SPC18 expression in ESCC cell lines. To examine cell viability, we performed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. The effects of SPC18 inhibition on epidermal growth factor receptor (EGFR) signaling were analyzed by Western blot. RESULTS: In total, 46 (50%) of 92 ESCC cases were positive for SPC18. SPC18 staining was observed more frequently in stage II/III/IV cases than in stage I cases (p = 0.028). We found that SPC18 expression was significantly associated with increased cancer-specific mortality (p = 0.006, log-rank test). SPC18 expression was frequently found in EGFR-positive cases compared with EGFR-negative cases. Cell proliferation and EGFR signaling were inhibited by SPC18 knockdown. CONCLUSION: Specific inhibitors of SPC18 may be promising anticancer drugs for patients with ESCC.

Automatic quantification of HER2 gene amplification in invasive breast cancer from chromogenic in situ hybridization whole slide images.

Human epidermal growth factor receptor 2 (HER2), a transmembrane tyrosine kinase receptor encoded by the ERBB2 gene on chromosome 17q12, is a predictive and prognostic biomarker in invasive breast cancer (BC). Approximately 20% of BC are HER2-positive as a result of ERBB2 gene amplification and overexpression of the HER2 protein. Quantification of HER2 is performed routinely on all invasive BCs, to assist in clinical decision making for prognosis and treatment for HER2-positive BC patients by manually counting gene signals. We propose an automated system to quantify the HER2 gene status from chromogenic in situ hybridization (CISH) whole slide images (WSI) in invasive BC. The proposed method selects untruncated and nonoverlapped singular nuclei from the cancer regions using color unmixing and machine learning techniques. Then, HER2 and chromosome enumeration probe 17 (CEP17) signals are detected based on the RGB intensity and counted per nucleus. Finally, the HER2-to-CEP17 signal ratio is calculated to determine the HER2 amplification status following the ASCO/CAP 2018 guidelines. The proposed method reduced the labor and time for the quantification. In the experiment, the correlation coefficient between the proposed automatic CISH quantification method and pathologist manual enumeration was 0.98. The p -values larger than 0.05 from the one-sided paired t -test ensured that the proposed method yields statistically indifferent results to the reference method. The method was established on WSI scanned by two different scanners. Through the experiments, the capability of the proposed system has been demonstrated.

Validation of mitotic cell quantification via microscopy and multiple whole-slide scanners.

BACKGROUND: The establishment of whole-slide imaging (WSI) as a medical diagnostic device allows that pathologists may evaluate mitotic activity with this new technology. Furthermore, the image digitalization provides an opportunity to develop algorithms for automatic quantifications, ideally leading to improved reproducibility as compared to the naked eye examination by pathologists. In order to implement them effectively, accuracy of mitotic figure detection using WSI should be investigated. In this study, we aimed to measure pathologist performance in detecting mitotic figures (MFs) using multiple platforms (multiple scanners) and compare the results with those obtained using a brightfield microscope. METHODS: Four slides of canine oral melanoma were prepared and digitized using 4 WSI scanners. In these slides, 40 regions of interest (ROIs) were demarcated, and five observers identified the MFs using different viewing modes: microscopy and WSI. We evaluated the inter- and intra-observer agreements between modes with Cohen's Kappa and determined "true" MFs with a consensus panel. We then assessed the accuracy (agreement with truth) using the average of sensitivity and specificity. RESULTS: In the 40 ROIs, 155 candidate MFs were detected by five pathologists; 74 of them were determined to be true MFs. Inter- and intra-observer agreement was mostly "substantial" or greater (Kappa = 0.594-0.939). Accuracy was between 0.632 and 0.843 across all readers and modes. After averaging over readers for each modality, we found that mitosis detection accuracy for 3 of the 4 WSI scanners was significantly less than that of the microscope (p = 0.002, 0.012, and 0.001). CONCLUSIONS: This study is the first to compare WSIs and microscopy in detecting MFs at the level of individual cells. Our results suggest that WSI can be used for mitotic cell detection and offers similar reproducibility to the microscope, with slightly less accuracy.

SEC11A Expression Is Associated with Basal-Like Bladder Cancer and Predicts Patient Survival.

OBJECTIVES: Bladder cancer (BC) is a common malignancy worldwide. Signal peptidase complex 18 (SPC18) protein, which is encoded by the SEC11A gene, is one of the subunits of the signal peptidase complex and induces transforming growth factor-α secretion. In the present study, we analyzed the expression and function of SPC18 protein in human BC. METHODS: Expression of SPC18 was analyzed by immunohistochemistry. RNA interference was used to inhibit SEC11A expression in BC cell lines. For constitutive expression of the SEC11A gene, a SEC11A expression vector was transfected into BC cell lines. To examine cell viability, we performed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Modified Boyden chamber assays were used to examine cell invasiveness. RESULTS: SPC18 was upregulated in 54% of 81 BC cases. SPC18 expression served as an independent prognostic classifier of patients with BC. SPC18-positive BC cases frequently expressed cytokeratin 5/6, a marker of basal-like BC. Cell growth and invasiveness were inhibited by SEC11A knockdown and enhanced by forced expression of SEC11A. CONCLUSION: These results indicate that SPC18 plays an important role in the progression of BC. Specific inhibitors of SPC18 may be promising anticancer drugs for patients with basal-like BC.

Molecular carcinogenesis of gastric cancer: Lauren classification, mucin phenotype expression, and cancer stem cells.

Gastric cancer (GC), one of the most common human cancers, is a heterogeneous disease with different phenotypes, prognoses, and responses to treatment. Understanding the pathogenesis of GC at the molecular level is important for prognosis prediction and determining treatments. Microsatellite instability (MSI), silencing of MLH1, MGMT, and CDKN2A genes by DNA hypermethylation, KRAS mutation, APC mutation, and ERBB2 amplification are frequently found in intestinal type GC. Inactivation of CDH1 and RARB by DNA hypermethylation, and amplification of FGFR and MET, are frequently detected in diffuse type GC. In addition, BST2 and PCDHB9 genes are overexpressed in intestinal type GC. Both genes are associated with GC progression. GC can be divided into gastric/intestinal mucin phenotypes according to mucin expression. MSI, alterations of TP73, CDH1 mutation, and DNA methylation of MLH are detected frequently in the gastric mucin phenotype. TP53 mutation, deletion of APC, and DNA methylation of MGMT are detected frequently in the intestinal mucin phenotype. FKTN is overexpressed in the intestinal mucin phenotype, and IQGAP3 is overexpressed in the gastric mucin phenotype. These genes are involved in GC progression. To characterize cancer stem cells, a useful method is spheroid colony formation. KIFC1 and KIF11 genes show more than twofold higher expression in spheroid-forming cells than that in parental cells. Both KIF genes are overexpressed in GC, and knockdown of these genes inhibits spheroid formation. Alterations of these molecules may be useful to understand gastric carcinogenesis. Specific inhibitors of these molecules may also be promising anticancer drugs.

TDO2 Overexpression Is Associated with Cancer Stem Cells and Poor Prognosis in Esophageal Squamous Cell Carcinoma.

OBJECTIVE: Esophageal cancer is one of the deadliest cancers in the world, and the main subtype is esophageal squamous cell carcinoma (ESCC), which comprises 90% of cases. Expression of tryptophan 2,3-dioxygenase (TDO2), an enzyme involved in tryptophan catabolism, has been linked with tumor survival and poor prognosis of brain and breast cancer. However, no studies have investigated the potential role of TDO2 in esophageal cancer. Here we explored the expression and biological significance of TDO2 in ESCC. METHODS: TDO2 protein expression was evaluated in 90 ESCC tissue samples by immunohistochemistry. TDO2 function in ESCC cell lines and spheroid colony formation were evaluated by RNA interference (RNAi). RESULTS: TDO2 overexpression was associated with tumor stage, recurrence status, and the CD44 cancer stem cell marker in ESCC. TDO2 overexpression was correlated with poor outcome of ESCC patients. Inhibition of TDO2 expression by RNAi in TE-10 and TE-11 cell lines reduced both the number and the size of spheroid colonies as well as cell proliferation. Knockdown of TDO2 expression also induced inactivation of the epidermal growth factor receptor signaling pathway. CONCLUSION: Our results imply that TDO2 could play an important role in the progression of ESCC. Furthermore, TDO2 may be a potential therapeutic target in ESCC.