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Pancreatic Neoplasms: HELP
Articles by Toshitaka Nagao
Based on 2 articles published since 2010
(Why 2 articles?)

Between 2010 and 2020, Toshitaka Nagao wrote the following 2 articles about Pancreatic Neoplasms.
+ Citations + Abstracts
1 Article Hypoxia-inducible factor-1α expression and gemcitabine chemotherapy for pancreatic cancer. 2011

Kasuya, Kazuhiko / Tsuchida, Akihiko / Nagakawa, Yuichi / Suzuki, Minako / Abe, Yuta / Itoi, Takao / Serizawa, Hiromi / Nagao, Toshitaka / Shimazu, Motohide / Aoki, Tatsuya. ·Department of Digestive Surgery, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan. kasuya-k@jcom.home.ne.jp ·Oncol Rep · Pubmed #21922147.

ABSTRACT: The normal pancreas has an abundant blood flow, in contrast to pancreatic cancer, which is a hypovascular tumor. During hypoxia under a hypovascular environment, the transcription factor hypoxia-inducible factor-1α (HIF-1α) is activated. High HIF-1α expression reduces sensitivity to gemcitabine (GEM) which is used as a treatment for pancreatic cancer. The objective of this study was to clarify HIF-1α expression in pancreatic cancer and the association of its effects to GEM treatment. We used the human pancreatic ductal carcinoma cell lines AsPC-1 and BxPC-3 to evaluate cell proliferation, HIF-1α protein expression and sensitivity to GEM in a hypoxic environment of 1% O2 in 48 pancreatic cancer patients who received adjuvant GEM treatment after pancreatectomy. We divided the patients according to HIF-1α expression and the presence of single nucleotide polymorphisms, and we based our evaluation on the adverse events associated with GEM chemotherapy and patient outcome. The hypoxic environment promoted cell proliferation, induced HIF-1α expression and increased GEM resistance, especially in AsPC-1 cells, which included a mutant homozygote for HIF-1α(C1772T). There were no significant differences between the HIF-1α(-) and HIF-1α(+) groups in either adverse events or patient outcomes. HIF-1α enhanced neo-microvascularity in a hypoxic environment and increased drug resistance. The period until recurrence was shorter in the patients with a strong HIF-1α expression, than that in those with a weak HIF-1α expression.

2 Article EUS elastography combined with the strain ratio of tissue elasticity for diagnosis of solid pancreatic masses. 2011

Itokawa, Fumihide / Itoi, Takao / Sofuni, Atsushi / Kurihara, Toshio / Tsuchiya, Takayoshi / Ishii, Kentaro / Tsuji, Shujiro / Ikeuchi, Nobuhito / Umeda, Junko / Tanaka, Reina / Yokoyama, Naoyuki / Moriyasu, Fuminori / Kasuya, Kazuhiko / Nagao, Toshitaka / Kamisawa, Terumi / Tsuchida, Akihiko. ·Department of Gastroenterology and Hepatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan. ·J Gastroenterol · Pubmed #21505859.

ABSTRACT: BACKGROUND: Recently, the usefulness of endoscopic ultrasound (EUS) elastography has been reported for the diagnosis of pancreatic lesions. In the present study, we retrospectively assessed EUS elastography as a diagnostic tool by evaluating tissue elasticity distribution and elasticity semiquantification, using the strain ratio (SR) of tissue elasticity, in patients with pancreatic masses. METHODS: One hundred and nine patients who underwent EUS elastography between September 2006 and May 2009 were retrospectively evaluated. The final diagnosis was chronic pancreatitis (CP) in 20 patients [6 with non-mass-forming pancreatitis, 7 with mass-forming pancreatitis (MFP), and 7 with autoimmune pancreatitis (AIP)], pancreatic cancer (PC) in 72, pancreatic neuroendocrine tumor (PNET) in 9, and normal pancreas in 8. The tissue elasticity distribution calculation was performed in real time, and the results were represented in color in fundamental B-mode imaging. In addition, we performed quantification using the SR (non-mass area/mass area). RESULTS: Elastography for all PC patients showed intense blue coloration, indicating malignant lesions. In contrast, MFP presented with a mixed coloration pattern of green, yellow, and low-intensity blue. Normal controls showed an even distribution of green to red. The mean SR was 23.66 ± 12.65 for MFP and 39.08 ± 20.54 for PC (P < 0.05). CONCLUSIONS: Endoscopic ultrasound elastography is a promising diagnostic tool for defining the tissue characteristics of pancreatic masses. In addition, semiquantitative analysis of elasticity using the SR may allow the differentiation of MFP from PC.