Hiroshi Ichikawa

Dr. Hiroshi Ichikawa

orcid

Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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31 October 2017 in Genome Medicine
Verified
Journal Article
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HIHiroshi Ichikawa
Hiroshi Ichikawa
MNMasayuki Nagahashi
Masayuki Nagahashi
YSYoshifumi Shimada
Yoshifumi Shimada
THTakaaki Hanyu
Takaaki Hanyu
TITakashi Ishikawa
Takashi Ishikawa
TWToshifumi Wakai
Toshifumi Wakai
Intertumoral heterogeneity represents a significant hurdle to identifying optimized targeted therapies in gastric cancer (GC). To realize precision medicine for GC patients, an actionable gene alteration-based molecular classification that directly associates GCs with targeted therapies is needed. A total of 207 Japanese patients with GC were included in this study. Formalin-fixed, paraffin-embedded (FFPE) tumor tissues were obtained from surgical or biopsy specimens and were subjected to DNA extraction. We generated comprehensive genomic profiling data using a 435-gene panel including 69 actionable genes paired with US Food and Drug Administration-approved targeted therapies, and the evaluation of Epstein-Barr virus (EBV) infection and microsatellite instability (MSI) status. Comprehensive genomic sequencing detected at least one alteration of 435 cancer-related genes in 194 GCs (93.7%) and of 69 actionable genes in 141 GCs (68.1%). We classified the 207 GCs into four The Cancer Genome Atlas (TCGA) subtypes using the genomic profiling data; EBV (N = 9), MSI (N = 17), chromosomal instability (N = 119), and genomically stable subtype (N = 62). Actionable gene alterations were not specific and were widely observed throughout all TCGA subtypes. To discover a novel classification which more precisely selects candidates for targeted therapies, 207 GCs were classified using hypermutated phenotype and the mutation profile of 69 actionable genes. We identified a hypermutated group (N = 32), while the others (N = 175) were sub-divided into six clusters including five with actionable gene alterations: ERBB2 (N = 25), CDKN2A, and CDKN2B (N = 10), KRAS (N = 10), BRCA2 (N = 9), and ATM cluster (N = 12). The clinical utility of this classification was demonstrated by a case of unresectable GC with a remarkable response to anti-HER2 therapy in the ERBB2 cluster. This actionable gene-based classification creates a framework for further studies for realizing precision medicine in GC.

2 July 2018 in World Journal of Surgical Oncology
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Journal Article
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HKHitoshi Kameyama
Hitoshi Kameyama
MNMasayuki Nagahashi
Masayuki Nagahashi
YSYoshifumi Shimada
Yoshifumi Shimada
YTYosuke Tajima
Yosuke Tajima
HIHiroshi Ichikawa
Hiroshi Ichikawa
TWToshifumi Wakai
Toshifumi Wakai
Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn’s disease (CD), is a chronic, idiopathic, repeated inflammatory disease. Colorectal cancer (CRC) that develops in patients with IBD is known as colitis-associated colorectal cancer (CAC), but the underlying carcinogenic mechanism remains unclear. Genomic analysis of sporadic CRC has been well described based on next-generation sequencing (NGS) data. Using NGS, we compared all exons of 415 cancer-associated genes in patients in Japan and the USA who had CRC and found similar genomic alteration patterns among the two populations. However, genomic analysis of CAC has not been thoroughly investigated. The molecular pathogenesis of CAC shares many features with sporadic CRC, but there are distinct variations in the time and frequency of some alterations. Gene alterations in CAC are gradually being elucidated using genomic sequencing analyses. Some studies have shown that gene alteration patterns differ between UC and CD. The carcinogenesis of CAC depends on unique environmental, genetic, and immunological factors. In this review, we have discussed the differences in genomic alterations between sporadic CRC and CAC. NGS in patients with IBD has the potential to detect early CAC and to suggest therapeutic targets.

6 October 2020 in Annals of Surgical Oncology
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Journal Article
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NSNatsuru Sudo
Natsuru Sudo
HIHiroshi Ichikawa
Hiroshi Ichikawa
YMYusuke Muneoka
Yusuke Muneoka
THTakaaki Hanyu
Takaaki Hanyu
YKYosuke Kano
Yosuke Kano
TWToshifumi Wakai
Toshifumi Wakai

3 September 2013 in Nutrients
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Journal Article
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KKKazuaki Kobayashi
Kazuaki Kobayashi
YKYu Koyama
Yu Koyama
SKShin-Ichi Kosugi
Shin-Ichi Kosugi
TITakashi Ishikawa
Takashi Ishikawa
KSKaoru Sakamoto
Kaoru Sakamoto
TWToshifumi Wakai
Toshifumi Wakai
We retrospectively examined esophageal cancer patients who received enteral nutrition (EN) to clarify the validity of early EN compared with delayed EN. A total of 103 patients who underwent transthoracic esophagectomy with three-field lymphadenectomy for esophageal cancer were entered. Patients were divided into two groups; Group E received EN within postoperative day 3, and Group L received EN after postoperative day 3. The clinical factors such as days for first fecal passage, the dose of postoperative albumin infusion, differences of serum albumin value between pre- and postoperation, duration of systematic inflammatory response syndrome (SIRS), incidence of postoperative infectious complication, and use of total parenteral nutrition (TPN) were compared between the groups. The statistical analyses were performed using Mann-Whitney U test and Chi square test. The statistical significance was defined as p < 0.05. Group E showed fewer days for the first fecal passage (p < 0.01), lesser dose of postoperative albumin infusion (p < 0.01), less use of TPN (p < 0.01), and shorter duration of SIRS (p < 0.01). However, there was no significant difference in postoperative complications between the two groups. Early EN started within 3 days after esophagectomy. It is safe and valid for reduction of albumin infusion and TPN, for promoting early recovery of intestinal movement, and for early recovery from systemic inflammation.

14 December 2022 in BMC Surgery
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Journal Article
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YKYosuke Kano
Yosuke Kano
HIHiroshi Ichikawa
Hiroshi Ichikawa
THTakaaki Hanyu
Takaaki Hanyu
YMYusuke Muneoka
Yusuke Muneoka
TITakashi Ishikawa
Takashi Ishikawa
TWToshifumi Wakai
Toshifumi Wakai
Background: Recent improvements in systemic chemotherapy have provided an opportunity for patients with stage IV gastric cancer (GC) to undergo conversion surgery (CS). The aim of this study was to evaluate the long-term outcomes of patients who underwent CS and to elucidate the prognostic factors for CS in stage IV GC. Methods: A total of 79 patients who underwent CS with the aim of R0 resection for stage IV GC at six institutions from January 2008 to July 2019 were enrolled. We retrospectively reviewed the clinicopathological data and prognosis. Results: Of the 79 patients, 23 (31.1%) had initially resectable disease (IR) before chemotherapy, defined as positive for cancer on peritoneal cytology (CY1), resectable hepatic metastasis, or para-aortic lymph node No. 16a2/b1 metastasis. Of the 56 remaining patients with primary unresectable disease, 39 had peritoneal dissemination. R0 resection was accomplished in 63 patients (79.7%). The 3-year OS rates for patients with IR and unresectable disease were 78.3% and 44.5%, respectively. Multivariate analysis showed that IR (P = 0.014) and R0 (P = 0.014) were statistically significant independent prognostic factors for favorable OS. Among patients with peritoneal dissemination alone, OS was significantly better for patients with R0 resection than for patients with R1/2 resection, with the 3-year OS rates of 65.5% and 23.1%, respectively (P = 0.011). Conclusions: CS is a treatment option for selected patients with stage IV GC. Patients with IR and patients who achieve R0 resection may obtain a survival benefit from CS.

Verified
Journal Article
Open access
PDF file
MIMayuko Ikarashi
Mayuko Ikarashi
JTJunko Tsuchida
Junko Tsuchida
MNMasayuki Nagahashi
Masayuki Nagahashi
STShiho Takeuchi
Shiho Takeuchi
KMKazuki Moro
Kazuki Moro
TWToshifumi Wakai
Toshifumi Wakai
Although numerous experiments revealed an essential role of a lipid mediator, sphingosine-1-phosphate (S1P), in breast cancer (BC) progression, the clinical significance of S1P remains unclear due to the difficulty of measuring lipids in patients. The aim of this study was to determine the plasma concentration of S1P in estrogen receptor (ER)-positive BC patients, as well as to investigate its clinical significance. We further explored the possibility of a treatment strategy targeting S1P in ER-positive BC patients by examining the effect of FTY720, a functional antagonist of S1P receptors, on hormone therapy-resistant cells. Plasma S1P levels were significantly higher in patients negative for progesterone receptor (PgR) expression than in those positive for expression (p = 0.003). Plasma S1P levels were also significantly higher in patients with larger tumor size (p = 0.012), lymph node metastasis (p = 0.014), and advanced cancer stage (p = 0.003), suggesting that higher levels of plasma S1P are associated with cancer progression. FTY720 suppressed the viability of not only wildtype MCF-7 cells, but also hormone therapy-resistant MCF-7 cells. Targeting S1P signaling in ER-positive BC appears to be a possible new treatment strategy, even for hormone therapy-resistant patients.