Naohide Oue

Abnormalities in mucosal immunity are involved in the onset and progression of ulcerative colitis (UC), resulting in a high incidence of colorectal cancer (CRC). While high-mobility group box-1 (HMGB1) is overexpressed during colorectal carcinogenesis, its role in UC-related carcinogenesis remains unclear. In the present study, we investigated the role of HMGB1 in UC-related carcinogenesis and sporadic CRC. Both the azoxymethane colon carcinogenesis and dextran sulfate sodium colitis carcinogenesis models demonstrated temporal increases in mucosal HMGB1 levels. Activated CD8+ cells initially increased and then decreased, whereas exhausted CD8+ cells increased. Additionally, we observed increased regulatory CD8+ cells, decreased naïve CD8+ cells, and decreased mucosal epithelial differentiation. In the in vitro study, HMGB1 induced energy reprogramming from oxidative phosphorylation to glycolysis in CD8+ cells and intestinal epithelial cells. Furthermore, in UC dysplasia, UC-related CRC, and hyperplastic mucosa surrounding human sporadic CRC, we found increased mucosal HMGB1, decreased activated CD8+ cells, and suppressed mucosal epithelial differentiation. However, we observed increased activated CD8+ cells in active UC mucosa. These findings indicate that HMGB1 plays an important role in modulating mucosal immunity and epithelial dedifferentiation in both UC-related carcinogenesis and sporadic CRC.

Purpose: Upper tract urothelial carcinoma (UTUC) can be divided into renal pelvis tumor (RPT) and ureteral tumor (UT) based on the tumor origin. This study aimed to evaluate the efficacy of neoadjuvant chemotherapy with gemcitabine and cisplatin (NAC-GC) in terms of the pathological outcomes and oncological prognoses in patients with UTUC. We also compared its efficacy between RPT and UT. Materials and Methods: Patients who underwent radical nephroureterectomy for clinical T (cT)3N0M0 UTUC between 1999 and 2021 were included. Patients who underwent NAC-GC and those who did not were included in the NAC-GC and non-NAC-GC groups, respectively. Based on the tumor origin, we divided patients with UTUC into RPT and UT groups. Oncological prognosis was assessed using progression -free survival (PFS) and overall survival. Results: Of 44 patients, 20 (45.5%) and 24 (54.5%) patients were in the NAC-GC and non-NAC-GC groups, respectively. The NAC-GC group had significantly lower pathological T stage and negative lymphovascular invasion (LVI), and a better PFS (p < .05) compared to those in the non-NAC-GC group. Among patients with RPT, the NAC-GC group had significantly negative LVI and better PFS than the non-NAC-GC group (p < .05). In contrast, in patients with UT, the NAC-GC group had no significant difference in pathological outcomes, and no significant difference in oncological prognosis was observed between the NAC-GC and non-NAC-GC groups. Conclusion: NAC-GC improves both pathological outcomes and oncological prognosis in patients with cT3N0M0 UTUC. With regard to tumor location, RPT has better pathological outcomes and oncological prognoses than UT.

Introduction: Gastric cancer (GC) remains a common health concern worldwide and is the third leading cause of death in Japan. It can be broadly classified into gastric and intestinal mucin phenotypes using immunohistochemistry. We previously reported numerous associations of kinesin family member (KIF) genes and mucin phenotypes with GC. However, no previous studies have reported on the importance of KIF18B in GC using immunostaining. Thus, in this study, we investigated the expression and functions of KIF18B, which is highly expressed in gastric mucin phenotype GC. Methods: We performed RNA-seq of gastric and intestinal mucin type GCs, and clinicopathological studies of the KIF18B we found were performed using 96 GC cases. We also performed functional analysis using GC-derived cell lines. Result: RNA-seq showed the upregulation of matrisome-associated genes in gastric mucin phenotype GC and a high expression of KIF18B. KIF18B was detected in 52 of the 96 GC cases (54%) through immunohistochemistry. Low KIF18B expression was significantly associated with poor overall survival (p < 0.01). Other molecules that were significantly associated with KIF18B were MUC5AC and claudin 18; these were also significantly associated with the gastric mucin phenotype. KIF18B small interfering RNA (siRNA)-transfected GC cells showed greater growth and spheroid colony formation than the negative control siRNA-transfected cells. Furthermore, expression of snail family transcriptional repressor 1 and cadherin 2 was significantly increased and that of cadherin 1 was significantly decreased in KIF18B siRNA-transfected GC cells. Conclusion: These findings not only suggest that KIF18B may be a useful prognostic marker, but also provide insight into the pathogenesis of the GC phenotype.

βIII‐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.

A novel large neutral amino acid transporter 1 (LAT1)-specific inhibitor, JPH203, is expected to cause cancer-specific starvation and possess anti-tumor effects; however, its anti-tumor mechanism for colorectal cancer (CRC) remains unclear. We analyzed LAT family gene expressions in public databases using UCSC Xena and evaluated LAT1 protein expression using immunohistochemistry in 154 cases of surgically resected CRC. We also evaluated mRNA expression using polymerase chain reaction in 10 CRC cell lines. Furthermore, JPH203 treatment experiments were conducted in vitro and in vivo using an allogeneic immune-responsive mouse model with abundant stroma created via the orthotopic transplantation of the mouse-derived CRC cell line CT26 and mesenchymal stem cells. The treatment experiments were followed by comprehensive gene expression analyses with RNA sequencing. Database analyses and immunohistochemistry research on clinical specimens revealed that LAT1 expression was cancer-dominant, and its increase was accompanied by tumor progression. In vitro, JPH203 was effective in an LAT1 expression-dependent manner. In vivo, JPH203 treatment considerably reduced tumor size and metastasis, and RNA sequencing-based pathway analysis showed that not only tumor growth and amino acid metabolism pathways, but also stromal activation-related pathways were suppressed. The results of the RNA sequencing were validated in the clinical specimens, as well as both in vitro and in vivo. LAT1 expression in CRC plays an important role in tumor progression. JPH203 may inhibit the progression of CRC and tumor stromal activity.

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.

Although radiotherapy is the standard treatment for Helicobacter pylori (Hp)-negative gastric mucosa-associated lymphoid tissue (MALT) lymphoma, eradication therapy using antibiotics and an acid secretion suppressor can sometimes induce complete remission. We explored predictive markers for the response to eradication therapy for gastric MALT lymphoma that were negative for both API2-MALT1 and Hp infection using comprehensive RNA sequence analysis. Among 164 gastric MALT lymphoma patients who underwent eradication therapy as primary treatment, 36 were negative for both the API2-MALT1 fusion gene and Hp infection. Based on eradication therapy efficacy, two groups were established: complete response (CR) and no change (NC). The Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that cancer-related genes and infection-related genes were highly expressed in the NC and CR groups, respectively. Based on this finding and transcription factor, gene ontology enrichment, and protein–protein interaction analyses, we selected 16 candidate genes for predicting eradication therapy efficacy. Real-time PCR validation in 36 Hp-negative patients showed significantly higher expression of olfactomedin-4 (OLFM4) and the Nanog homeobox (NANOG) in the CR and NC groups, respectively. OLFM4 and NANOG could be positive and negative predictive markers, respectively, for eradication therapy efficacy against gastric MALT lymphoma that is negative for both API2-MALT1 and Hp infection.

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.

Background: We sought to identify an optimal combination of survival risk stratification markers in patients with pathological (p) stage II/III gastric cancer (GC) after curative resection. Methods: We measured the expression levels of 127 genes in pStage II/III GC tissues of two patient cohorts by quantitative polymerase chain reaction (qPCR) and the expression of 1756 proteins between two prognosis (good and poor) groups by proteomic analysis to identify candidate survival stratification markers. Further, immunohistochemistry (IHC) using tumor microarrays (TMAs) in another cohort of patients was performed to identify an optimal biomarker combination for survival stratification in GC patients. Results: secreted protein acidic and rich in cysteine (SPARC), erb-b2 receptor tyrosine kinase 2 (ERBB2), inhibin subunit beta A (INHBA), matrix metallopeptidase-11 (MMP11), tumor protein p53 (TP53), and platelet-derived growth factor receptor-beta (PDGFRB) were identified as candidate biomarkers from qPCR analysis, and SPARC and galectin-10 were obtained from the proteomic analysis. The combination of PDGFRB, INHBA, MMP11, and galectin-10 was identified as the optimal combination of survival risk stratification markers. Conclusions: A combination of four proteins in GC tissues may serve as useful survival risk stratification markers in patients with pStage II/III GC following curative resection. Our results may facilitate future multicenter prospective clinical trials.

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.