ドパミンD1シグナルの阻害はWNTシグナルを通じてヒト胆道癌の進行を促進する

京都大学新制・課程博士博士(医学)甲第24499号医博第4941号新制||医||1064(附属図書館)京都大学大学院医学研究科医学専攻(主査)教授 伊藤 貴浩, 教授 中島 貴子, 教授 藤田 恭之学位規則第4条第1項該当Doctor of Medical ScienceKyoto UniversityDFA

SNAIL2 contributes to tumorigenicity and chemotherapy resistance in pancreatic cancer by regulating IGFBP2

Pancreatic cancer has an extremely poor prognosis because of its resistance to conventional therapies. Cancer stem cell (CSC)-targeted therapy is considered a promising approach for this disease. Epithelial-mesenchymal transition-inducing transcription factors (EMT-TFs) contribute to CSC properties in some solid tumors; however, this mechanism has not been fully elucidated in pancreatic cancer. Zinc finger protein, SNAIL2 (also known as SLUG), is a member of the SNAIL superfamily of EMT-TFs and is commonly overexpressed in pancreatic cancer. Patients exhibiting high SNAIL2 expression have a poor prognosis. In this study, we showed that the suppression of SNAIL2 expression using RNA interference decreased tumorigenicity in vitro (sphere formation assay) and in vivo (xenograft assay) in 2 pancreatic cancer cell lines, KLM1 and KMP5. In addition, SNAIL2 suppression resulted in increased sensitivity to gemcitabine and reduced the expression of CD44, a pancreatic CSC marker. Moreover, experiments on tumor spheroids established from surgically resected pancreatic cancer tissues yielded similar results. A microarray analysis revealed that the mechanism was mediated by insulin-like growth factor (IGF) binding protein 2. These results indicate that IGFBP2 regulated by SNAIL2 may represent an effective therapeutic target for pancreatic cancer

Establishment of patient-derived organoids and a characterization-based drug discovery platform for treatment of pancreatic cancer

BACKGROUND: Pancreatic cancer is one of the most lethal tumors. The aim of this study is to provide an effective therapeutic discovery platform for pancreatic cancer by establishing and characterizing patient-derived organoids (PDOs). METHODS: PDOs were established from pancreatic tumor surgical specimens, and the mutations were examined using a panel sequence. Expression of markers was assessed by PCR, immunoblotting, and immunohistochemistry; tumorigenicity was examined using immunodeficient mice, and drug responses were examined in vitro and in vivo. RESULTS: PDOs were established from eight primary and metastatic tumors, and the characteristic mutations and expression of cancer stem cell markers and CA19-9 were confirmed. Tumorigenicity of the PDOs was confirmed in subcutaneous transplantation and in the peritoneal cavity in the case of PDOs derived from disseminated nodules. Gemcitabine-sensitive/resistant PDOs showed consistent responses in vivo. High throughput screening in PDOs identified a compound effective for inhibiting tumor growth of a gemcitabine-resistant PDO xenograft model. CONCLUSIONS: This PDO-based platform captures important aspects of treatment-resistant pancreatic cancer and its metastatic features, suggesting that this study may serve as a tool for the discovery of personalized therapies

Preoperative risk stratification of lymph node metastasis for non-functional pancreatic neuroendocrine neoplasm: An international dual-institutional study

BACKGROUND: /Objectives: Although the presence of lymph node metastasis (LNM) defines malignant potential, preoperative prediction of LNM has not been established for non-functional pancreatic neuroendocrine neoplasm (NF-PNEN). We sought to develop a prediction system using only preoperatively available factors that would stratify the risk of LNM for NF-PNEN. METHODS: We retrospectively reviewed patients who underwent R0/1 resection of NF-PNEN at Kyoto University (2007-2019) and the University of California, San Francisco (2010-2019). Risk stratification of LNM was developed using preoperative factors by the logistic regression analysis. Long-term outcomes were compared across the risk groups. RESULTS: A total of 131 patients were included in this study. Lymph nodes were pathologically examined in 116 patients, 23 (20%) of whom had LNM. Radiological tumor size [1.5-3.5 cm (odds ratio: 13.5, 95% confidence interval: 1.77-398) and >3.5 cm (72.4, 9.06-2257) against ≤1.5 cm], <50% cystic component (8.46 × 10^6, 1.68 × 10^106-), and dilatation of main pancreatic duct ≥5 mm (31.2, 3.94-702) were independently associated with LNM. When patients were classified as the low-risk (43 patients), intermediate-risk (44 patients), and high-risk groups (29 patients), proportions of LNM differed significantly across the groups (0%, 14%, and 59%, respectively). Recurrence-free survival (RFS) of the low- and intermediate-risk groups were significantly better than that of the high-risk group (5-year RFS rates of 92.2%, 85.4%, and 47.1%, respectively). CONCLUSIONS: The prediction system using preoperative radiological factors stratifies the risk of LNM for NF-PNEN. This stratification helps to predict malignant potential and determine the surgical procedure and necessity of regional lymphadenectomy

Impact of neoadjuvant intensity-modulated radiation therapy on borderline resectable pancreatic cancer with arterial abutment; a prospective, open-label, phase II study in a single institution

BACKGROUND: Borderline resectable pancreatic cancer (BRPC) is a category of pancreatic cancer that is anatomically widely spread, and curative resection is uncommon with upfront surgery. Intensity-modulated radiation therapy (IMRT) is a form of radiation therapy that delivers precise radiation to a tumor while minimizing the dose to surrounding normal tissues. Here, we conducted a phase 2 study to estimate the curability and efficacy of neoadjuvant chemoradiotherapy using IMRT (NACIMRT) for patients with BRPC with arterial abutment (BRPC-A). METHODS: A total of 49 BRPC-A patients were enrolled in this study and were treated at our hospital according to the study protocol between June 2013 and March 2021. The primary endpoint was microscopically margin-negative resection (R0) rates and we subsequently analyzed safety, histological effect of the treatment as well as survivals among patients with NACIMRT. RESULTS: Twenty-nine patients (59.2%) received pancreatectomy after NACIMRT. The R0 rate in resection patients was 93.1% and that in the whole cohort was 55.1%. No mortality was encountered. Local therapeutic effects as assessed by Evans classification showed good therapeutic effect (Grade 1, 3.4%; Grade 2a, 31.0%; Grade 2b, 48.3%; Grade 3, 3.4%; Grade 4, 3.4%). Median disease-free survival was 15.5 months. Median overall survival in the whole cohort was 35.1 months. The only independent prognostic pre-NACIMRT factor identified was serum carbohydrate antigen 19-9 (CA19-9) > 400 U/ml before NACIMRT. CONCLUSIONS: NACIMRT showed preferable outcome without significant operative morbidity for BRPC-A patients. NACIMRT contributes to good local tumor control, but a high initial serum CA19-9 implies poor prognosis even after neoadjuvant treatment. TRIAL REGISTRATION: UMIN-CTR Clinical Trial: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000011776 Registration number: UMIN000010113. Date of first registration: 01/03/2013

EMT関連因子SNAILは、2つの遺伝子CCN3 およびNEFLを通 じて胃発癌を制御する

Among cancer cells, there are specific cell populations of whose activities are comparable to those of stem cells in normal tissues, and for whom the levels of cell dedifferentiation are reported to correlate with poor prognosis. Information concerning the mechanisms that modulate the stemness like traits of cancer cells is limited. Therefore, we examined five gastric cancer cell lines and isolated gastric oncospheres from three gastric cancer cell lines. The gastric cancer cells that expanded in the spheres expressed relatively elevated proportion of CD44, which is a marker of gastric cancer stem cells (CSCs), and displayed many properties of CSCs, for example: chemoresistance, tumorigenicity and epithelial–mesenchymal transition (EMT) acquisition. SNAIL, which is a key factor in EMT, was highly expressed in the gastric spheres. Microarray analysis in gastric cancer cell line HGC27 showed that CCN3 and NEFL displayed the greatest differential expression by knocking down of SNAIL; the former was upregulated and the latter downregulated, respectively. Downregulation of CCN3 and upregulation of NEFL gene expression impaired the SNAIL-dependent EMT activity: high tumorigenicity, and chemoresistance in gastric cancer cells. Thus, approach that disrupts SNAIL/CCN3/NEFL axis may be credible in inhibiting gastric cancer development

Safety and efficacy of neoadjuvant chemoradiotherapy with moderately hypofractionated intensity‐modulated radiotherapy for resectable pancreatic cancer: A prospective, open‐label, phase II study

Abstract Background Resectable pancreatic cancer (RPC) is potentially resectable on admission, and the impact of neoadjuvant therapy on these tumors is controversial. Moreover, the safety and efficacy of neoadjuvant chemoradiotherapy with moderately hypofractionated intensity‐modulated radiation therapy (NACIMRT) for RPC have not been studied. Here, we conducted a phase II study to evaluate the safety and efficacy of hypofractionated NACIMRT for RPC. Methods A total of 54 RPC patients were enrolled and treated according to the study protocol. We used moderately hypofractionated (45 Gy in 15 fractions) IMRT with gemcitabine to shorten the duration of radiotherapy and reduce gastrointestinal toxicity. The primary endpoint was overall survival (OS), and we subsequently analyzed the microscopically margin‐negative resection (R0) rate, disease‐free survival (DFS), and histologic effects and safety of NACIMRT. Results Median OS for the cohort was 40.0 months. Forty‐two patients (77.8%) underwent pancreatectomy after NACIMRT. Median DFS was 20.3 months. The R0 resection rate was 95.2% (40/42) per protocol and 85.2% (46/54) for the cohort. There were no intervention‐related deaths during the study period. Local treatment response, as assessed by the CAP classification, showed no residual tumor in 4.8% of patients. Overall, 23.9% of patients experienced CTCAE grade 3 or 4 during NACIMRT. Adjuvant therapy was initiated in 88% of patients undergoing resection. Postoperative complications grade ≥3b on the Clavien–Dindo scale occurred in 4.8% of patients. CA19‐9 level at enrollment was an independent prognostic factor for OS and DFS. Conclusions This is the first prospective study of hypofractionated IMRT as neoadjuvant therapy for RPC. Hypofractionated NACIMRT for RPC could be safely introduced with a high induction rate of adjuvant chemotherapy, with an overall survival of 40.0 months