Published papers

Background: While monoclonal antibodies are widely accepted as being powerful in molecular targeting therapy, the activation of immunity by the B cell receptor epitope peptide has not been reported. Our objective was to evaluate a 20-mer multiple antigen peptide containing the anti-erbB-2 (HER2/neu) monoclonal antibody epitope (N: 163-182), designated as CH401MAP, as a general peptide vaccine for Japanese breast cancer patients. Methods: The 20-mer CH401 epitope peptide binding to the human leukocyte antigen (HLA) of Japanese breast cancer patients was predicted by algorithms from the following databases: SYFPEITHI, Bioinformatics and Molecular Analysis Section (BIMAS), and Immune Epitope Database (IEDB). Peripheral blood mononuclear cells (PBMCs) were collected from 173 breast cancer patients and stimulated with the peptide in vitro. Cytokine secretion was examined by enzyme-linked immunosorbent assay (ELISA). Flow cytometric analysis was performed to detect CD4 and CD8 T cells and Treg cells. Results: Using the algorithms used for the simulation, CH401MAP was predicted to bind to more than 90% of class I HLAs and to 30-50% of class II HLAs in breast cancer patients. In vitro stimulation of patients' PBMCs with CH401MAP induced a significant increase in interleukin-2 secretion, proliferation, and CD8 T cell ratios. Conclusions: Our study demonstrates that CH401MAP induces T cell activation in PBMCs derived from breast cancer patients. This antibody epitope-based peptide with HLA motifs could be a candidate peptide vaccine for general breast cancer. © 2012 Tsuda B, et al.

Duodenal atresia concomitant with type-A esophageal atresia (DA + TA-EA) is rare. A pronounced enlargement of a closed loop of the upper gastrointestinal tract serves as an early clue for its prenatal detection. We describe an atypical case of DA + TA-EA in which the dilatation of the upper gastrointestinal tract remained mild. Ultrasonographic examination at 28 weeks of gestation showed mild polyhydramnios. Subsequent detailed sonographic and magnetic resonance imaging studies revealed a mildly enlarged stomach and duodenum that resembled a "double bubble," mild ascites, and polydactyly of the right thumb. Fetal abdominal circumference measurements were within normal range. A female neonate born at 36 weeks gestation did not show abdominal distension. DA + TA-EA was diagnosed based on clinical characteristics and X-ray studies of the neonate; the diagnosis was confirmed by surgery. Duodenoduodenostomy and gastrostomy in the first week of life and esophagoesophagostomy at six months of age were performed with satisfactory results, and the infant developed well. Prominent and/or increasing C-shaped fluid collection in the upper abdomen is a highly useful diagnostic sign for DA + TA-EA, but it is not applicable for all fetuses with this disease. Physicians should bear this caveat in mind to avoid diagnostic delays and initiate prompt postnatal therapy.

T cell stimulation by bacterial superantigens induces a cytokine storm. After T cell activation and inflammatory cytokine secretion, regulatory T cells (Treg) are produced to suppress the immune response. Coccomyxa sp.KJ (IPOD FERM BP-22254), a green alga, is reported to regulate immune reactions. Therefore, we examined the effects of Coccomyxa sp.KJ extract (CE) on the superantigen-induced immune response. When human peripheral blood mononuclear cells (PBMCs) were stimulated with toxic shock syndrome-1 (TSST-1) in the presence of CE, the number of activated T cells decreased moderately. Purified T cells stimulated in the presence of CE comprised more non-proliferating cells than those stimulated in the absence of CE, whereas some T cells proliferated more quickly. The levels of activation markers on the stimulated T cells increased in the presence of CE. Most of the inflammatory cytokines did not change but IL-1β, IL-17, IL-4, and IL-13 secretion increased, whereas that of IL-2, TNF-α, and IL-18 decreased. IL-10 secretion was also decreased by CE treatment, suggesting that the immune response was not suppressed by Treg cells. CE enhanced the expression of stem cell-like memory cell markers in T cells. These results suggest that CE can regulate the fate of T cells and can help to ameliorate superantigen-induced T cell hyperactivation and immune suppression.

Coccomyxa subellipsoidea KJ (C-KJ) is a green alga with unique immunoregulatory characteristics. Here, we investigated the mechanism underlying the modification of T cell function by C-KJ components. The water-soluble extract of C-KJ was fractionated into protein (P) and sugar (S) fractions acidic (AS), basic (BS), and neutral (NS). These fractions were used for the treatment of peripheral blood mononuclear cells stimulated with toxic shock syndrome toxin-1. Transcriptome analysis revealed that both P and AS enhanced the expression of the genes encoding metallothionein (MT) family proteins, inflammatory factors, and T helper (Th) 17 cytokine and suppressed that of those encoding Th2 cytokines in stimulated T cells. The kinetics of MT1 and MT2A gene expression showed a transient increase in MT1 and maintenance of MT2A mRNA after T cell stimulation in the presence of AS. The kinetics of Th17-related cytokine secretion in the early period were comparable to those of MT2A mRNA. Furthermore, our findings revealed that static, a STAT-3 inhibitor, significantly suppressed MT2A gene expression. These findings suggest that the expression of MTs is involved in the immune regulatory function of C-KJ components, which is partially regulated by Th17 responses, and may help develop innovative immunoregulatory drugs or functional foods.

Immune checkpoint inhibitors highlight the importance of anticancer immunity. However, their clinical utility and safety are limited by the low response rates and adverse effects. We focused on progesterone (P4), a hormone produced by the placenta during pregnancy, because it has multiple biological activities related to anticancer and immune regulation effects. P4 has a reversible immune regulatory function distinct from that of the stress hormone cortisol, which may drive irreversible immune suppression that promotes T cell exhaustion and apoptosis in patients with cancer. Because the anticancer effect of P4 is induced at higher than physiological concentrations, we aimed to develop a new anticancer drug by encapsulating P4 in liposomes. In this study, we prepared liposome-encapsulated anti-programmed death ligand 1 (PD-L1) antibody-conjugated P4 (Lipo-anti-PD-L1-P4) and evaluated the effects on the growth of MDA-MB-231 cells, a PD-L1-expressing triple-negative breast cancer cell line, in vitro and in NOG-hIL-4-Tg mice transplanted with human peripheral blood mononuclear cells (humanized mice). Lipo-anti-PD-L1-P4 at physiological concentrations reduced T cell exhaustion and proliferation of MDA-MB-231 in vitro. Humanized mice bearing MDA-MB-231 cells expressing PD-L1 showed suppressed tumor growth and peripheral tissue inflammation. The proportion of B cells and CD4+ T cells decreased, whereas the proportion of CD8+ T cells increased in Lipo-anti-PD-L1-P4-administrated mice spleens and tumor-infiltrated lymphocytes. Our results suggested that Lipo-anti-PD-L1-P4 establishes a systemic anticancer immune environment with minimal toxicity. Thus, the use of P4 as an anticancer drug may represent a new strategy for cancer treatment.

High-grade serous carcinoma (HGSC), the most aggressive subtype of epithelial ovarian cancer, is strongly associated with hereditary breast and ovarian cancer (HBOC) syndrome and is primarily linked to germline BRCA1/2 pathogenic variants (PVs). The cumulative risks of ovarian cancer by the age of 70 years are 40% and 18% for carriers of BRCA1 and BRCA2 PVs, respectively. Risk-reducing salpingo-oophorectomy (RRSO) is a recommended preventive strategy that reduces the risk of ovarian cancer by more than 80% and may improve overall survival. However, surgical menopause after RRSO poses several challenges, including infertility and hormonal deficiency. Although the use of hormone replacement therapy may alleviate symptoms, it requires careful consideration of breast cancer risk. Emerging strategies, such as prophylactic salpingectomy with delayed oophorectomy, are being investigated to balance cancer prevention and patient quality of life. Further research is required to refine personalized prevention and management approaches for HBOC-associated ovarian cancer.

Tropomyosin-related kinase B (TrkB) is a functional signal molecule that correlates with cell survival and epithelial-mesenchymal transition (EMT), which is essential for the invasiveness of malignant cancer cells. While a truncated isoform of TrkB has a dominant negative effect, full-length TrkB with its tyrosine kinase domain is predicted to play a role in cancer progression. Because ovarian clear cell adenocarcinoma (CCA) shows worse prognosis compared to other cancer types, we investigated the correlation between TrkB isoforms and the progression of CCA. Ovarian adenocarcinoma and benign tumor samples were obtained from Tokai University Hospital and Juntendo University Hospital. These samples were examined for the TrkB expression of isotype-specific proteins and mRNAs by immunohistochemistry and domain-specific semi-quantitative reverse transcription polymerase chain reaction. While TrkB mRNA expression was detected in all of the ovarian tissues and TrkB protein expression was predominant in ovarian cancer tissues, the number of tissues expressing the tyrosine kinase-truncated isoforms (T-Shc or T1) decreased according to the clinical stage of CCA. Irregular isoforms were also observed in some CCA samples. The decrease in T-Shc and T1 were less obvious in mucinous adenocarcinoma and not observed in serous or endometrioid adenocarcinoma. Decreased expression of the truncated isoforms (T-Shc and T1) was associated with CCA progression. These results demonstrate that irregular expression of TrkB isoforms is a characteristic of CCA tissues. The unique TrkB expression profile may be useful for the diagnosis of CCA subtypes.

Objectives: It is well known that a poorly differentiated endometrial adenocarcinoma shows more rapid progression and aworse response to therapy than awell-differentiated endometrial adenocarcinoma. Qualitative and quantitative changes of cell surface glycolipids occur during neoplastic transformation. Sulfatide is one of the sulfated glycolipids in the cell membrane that may have an important role in various functions such as cell adhesion. To examine the molecular background of the morphological and biological features of well-differentiated and poorly differentiated cancer, we measured the levels of lipids, especially glycolipids, in tumor tissues from patients with endometrial carcinoma. Materials and Methods: We determined the composition of lipids and glycolipids in tumor tissues, investigated glycosyltransferase messenger RNA expression by the reverse transcription-polymerase chain reaction, and assessed the localization of galactosylceramide sulfotransferase (an enzyme involved in sulfatide biosynthesis) by immunohistochemical staining. Results: No significant differences were observed between well-differentiated and poorly differentiated cancer with respect to the levels of cholesterol ester, cholesterol, phospholipids, cholesterol sulfate, ceramides, neutral glycolipids of the globo series, and GM3 ganglioside. However, the amount of sulfatides in well-differentiated tumors was significantly greater than that in poorly differentiated tumors, which was confirmed by thin-layer chromatography and immunostaining with a monoclonal antisulfatide antibody. Altered expression of sulfatide was found to be secondary to a change of galactosylceramide sulfotransferase messenger RNA expression. Immunohistochemical staining revealed that galactosylceramide sulfotransferase expression was characteristically observed in glandular areas but not in solid areas. Conclusion: These findings suggest that sulfatide contributes to the well-differentiated phenotype of endometrial adenocarcinoma and that it is being expressed in normal uterine endometrium at sites of gland formation during the luteal phase, as we have previously reported. Copyright © 2012 by IGCS and ESGO.

In Japan, the rising incidence of hereditary breast and ovarian cancer syndrome (HBOC) follows partial insurance coverage introduced in 2020. Compared with the general population (~11% lifetime risk), individuals with HBOC face a significantly higher lifetime risk of breast cancer (48%–76%), often presenting at younger ages. BRCA1 mutations are linked to triple-negative breast cancer, whereas BRCA2 mutations typically result in luminal-type disease. Key risk management strategies include surveillance and prophylactic surgery. Annual magnetic resonance imaging and mammography are recommended at younger ages than in the general population, despite concerns regarding contrast agents, radiation exposure, and examination-related burdens. Although risk-reducing mastectomy lowers breast cancer risk by over 90%, it remains underutilized because of cosmetic and psychological considerations. Nipple-sparing or skin-sparing mastectomy combined with immediate or delayed reconstruction offers a balance between risk reduction and postoperative outcomes, although safety and procedure details still warrant careful evaluation. Managing the high breast cancer risk associated with HBOC requires ongoing efforts to refine current strategies while minimizing patient burden.

Progesterone (P4) and glucocorticoid (GC) play crucial roles in the immunoregulation of a mother to accept and maintain a semi-allogenic fetus. P4 concentration increases during pregnancy and becomes much higher in the placenta than in the other peripheral tissues, wherein the concentration of cortisol (COR), the most abundant GC and a strong immunosuppressor, remains uniform throughout the rest of the body. Here, we evaluated the effect of a high-P4 environment on pregnant immunity by comparing it with COR. Naïve T cell proportion increased transiently in peripheral blood of pregnant women just after delivery and decreased after one month. T cells stimulated with superantigen toxic-shock-syndrome-1 (TSST-1) in the presence of P4 stayed in the naïve state and did not increase, irrespective of the presence of COR, and reactive T cells could not survive. Treatment of T cells with P4 without T cell receptor (TCR) stimulation transiently suppressed T cell activation and proliferation, whereas the levels remain unaltered if P4 was not given before stimulation. Comparison of the engraftment and response against specific antigens using hu-PBL-NOG-hIL-4-Tg mice showed that P4-pretreated lymphocytes preserved CD62L expression and engrafted effectively in the spleen. Moreover, they produced antigen-specific antibodies, whereas COR-pretreated lymphocytes did not. These results suggest that a high-P4 environment suppresses T cell activation and induces T cell migration into lymphoid tissues, where they maintain the ability to produce anti-pathogen antibodies, whereas COR does not preserve T cell function. The mechanism may be pivotal in maintaining non-fetus-specific T cell function in pregnancy.

This study aimed to promote gland formation in cells derived from endometrial cancer, and assess the relevance of sulfolipids by performing culture with type I collagen. Tumors were developed in nude mice using cultured cell lines, gland formation was induced by culture with type I collagen and the composition of tumor cell sulfolipids was analyzed. Results showed that after culturing the cells on type I collagen gel, the gel was floated. Another layer of gel was placed on top so that the cells were sandwiched between two layers. Using this method, it was possible to induce gland formation in cells that formed only poorly differentiated tumors in nude mice. Mucous staining and electron microscopy demonstrated polarity of the glands. The cell lines that showed gland formation expressed sulfolipids, but not cholesterol sulfate. In conclusion, type I collagen and sulfolipids are involved in the process of gland formation in endometrioid adenocarcinoma.

OBJECTIVE: We assessed the clinical characteristics and perinatal outcome of disorders specific to monochorionic diamniotic (MD) twin pregnancies, focusing on twin-twin transfusion syndrome (TTTS) and related disorders, such as selective intrauterine growth restriction (sIUGR), inter-twin amniotic fluid discordance (AFD), and twin anemia polycythemia sequence (TAPS). METHODS: We retrospectively reviewed 69 cases of MD twin pregnancies delivered after 22 weeks at our institution from January 2009 to September 2013. RESULTS: TTTS occurred in 9 cases (13%). There was a total of 11 cases (16%) of MD twins with sIUGR in this period. One case developed TTTS. All 3 cases (4%) of AFD in this study developed TTTS or sIUGR. CONCLUSION: AFD should be recognized as predictors of TTTS or sIUGR. Further studies on TTTS-related disorders allow a more precise subgroup categorization that enables optimal management.

A program of recruiting families with hereditary pancreatic cancer and hereditary breast and ovarian cancer (HBOC) syndrome as high-risk individuals for pancreatic cancer surveillance using magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasound (EUS) has proven effective, resulting in the improvement of early detection rates and life expectancy. Given this, recent guidelines recommend pancreatic surveillance for patients with familial pancreatic cancer and pathological variants of ten genes, including BRCA1/2. In April 2021, our hospital established the HBOC Center, which is operated by nine departments, including obstetrics and gynecology, breast surgery, pancreatology, urology, medical genetics, dermatology, psychiatry and neurology, and oncology. Currently, MRCP or EUS is performed once or twice a year in 63 cases with pathogenic variants in 54 families. Although 4 cases (6.3%) revealed pancreatic microcysts or branched intraductal papillary mucinous neoplasms, no sign of pancreatic cancer was detected. Since January 2021, the germline BRCA1/2 test for companion diagnosis of pancreatic cancer has been covered by insurance, improving the accessibility of genetic testing among patients with pancreatic cancer. However, the BRCA1/2 positivity rate remains low at 1.3%, and its indication for use is very limited. The implementation of genetic testing, including BRCA1/2 analysis, is necessary for the prevention and early detection of pancreatic cancer in high-risk families.

Hereditary breast and ovarian cancer syndrome (HBOC) is traditionally associated with mutations in the BRCA1 and BRCA2 genes, predominantly impacting breast, ovarian, pancreatic, and prostate cancers. However, recent research suggests that these mutations may also predispose carriers to a broader spectrum of malignancies, including biliary tract, cervical, colorectal, endometrial, esophageal, and gastric cancers. This review presents findings from extensive datasets, including a significant study from a nationwide Japanese biobank that examined cancer risks in 63,828 patients and 37,086 controls. Our review highlights notable associations, such as an increased risk of uterine and cervical cancers in BRCA1 mutation carriers and increased risk of esophageal and gastric cancers in BRCA2 mutation carriers. These emerging associations underscore the necessity of revisiting and potentially expanding current clinical guidelines to incorporate these additional risks. These findings advocate a comprehensive approach to genetic counseling and underscore the importance of tailored cancer surveillance strategies in populations carrying BRCA mutations. This expanded understanding could significantly influence preventive, diagnostic, and therapeutic strategies, promoting personalized approaches to manage and potentially prevent these malignancies in genetically susceptible populations.

Reflex sympathetic dystrophy (RSD), currently categorized within the spectrum of complex regional pain syndrome (CRPS), is typically considered an acquired disorder characterized by disproportionate pain, erythema, and autonomic changes. In contrast, inherited erythromelalgia is a genetic pain disorder most often caused by gain-of-function variants in SCN9A encoding the Nav1.7 sodium channel and usually presents with bilateral, symmetric distal limb pain and redness. Here, we describe a multigenerational family with a strictly unilateral, trauma-triggered neurovascular pain phenotype associated with a previously unreported heterozygous germline SCN9A variant (c.4784T > G, p. Leu1595Arg). Affected individuals experienced episodic attacks in which minor mechanical or physiological stimuli induced progressive unilateral erythema, warmth, and severe pain spreading from the site of injury and sharply demarcated at the midline, without contralateral involvement. Attacks lasted hours to nearly one day and tended to decrease with age. The variant was absent from population databases and co-segregated with the phenotype within the family, fulfilling ACMG/AMP criteria for likely pathogenicity. The consistent unilateral distribution cannot be explained by mosaicism and is instead compatible with activation of ipsilateral segmental nociceptive and neurovascular reflex circuits that function largely independently across the spinal midline. We propose that excessive positive feedback between C-fiber activation and axon reflex-mediated neurogenic inflammation underlies attack propagation and duration. This framework also suggests therapeutic benefit from agents that interrupt activity-dependent transmitter release, such as gabapentinoids. These findings expand the phenotypic spectrum of SCN9A-related pain disorders and provide a genetically anchored model for unilateral RSD/CRPS-like neurovascular pain.

Retained products of conception (RPOC) refer to the persistence of placental or fetal tissue in the uterus following delivery or miscarriage. RPOC may cause massive postpartum or post-abortion hemorrhage. Arterial embolization (AE) is an effective choice of management for postpartum hemorrhage including RPOC. We report a case of hemorrhagic RPOC, in which uterine artery embolization with transcervical resection did not achieve hemostasis, and laparotomy with uterine compression sutures was subsequently required. The RPOC was apparently fed by an aberrant branch derived from the inferior mesenteric artery (IMA). AE of IMA was not performed because of possible necrosis of the descending colon and rectum. A physician should be aware that AE is not an all-encompassing hemostatic technique for postpartum bleeding, such as with RPOC, and should keep alternatives in mind.

The management of hereditary breast and ovarian cancer (HBOC) in Japan has changed drastically with the expansion of indications for poly ADP-ribose polymerase inhibitors, the increase in diagnostic opportunities with the spread of companion diagnoses, and partial insurance coverage of HBOC management. These circumstances require a response that is coordinated across the entire hospital rather than from individual departments. In April 2021, we established the HBOC Center, which is operated by nine departments: Obstetrics and Gynecology, Reproduction, Surgery (breast group, hepato-pancreato-biliary group), Urology, Dermatology, Neuropsychiatry, the Center for Medical Genetics, and the Cancer Center. In addition to discussions of individual cases, our monthly conferences have enabled us to establish indication criteria and appropriate items for surveillance, visualize the examination flow in the hospital, construct a patient database, and provide open lectures to educate the public. The future HBOC management system should not only fulfill the existing requirements for risk-reducing surgery and facility standards but also offer comprehensive and diversified attention based on the needs of patients and their family members.

Hereditary breast and ovarian cancer (HBOC) syndrome, caused by pathogenic variants in BRCA1 or BRCA2, is associated with increased risks of breast, ovarian, pancreatic, and prostate cancers. Although long-term, multi-organ surveillance is recommended, real-world data on its implementation in Japan remain limited. We conducted a web-based cross-sectional survey among 274 individuals registered for a hybrid public lecture at Keio University Hospital in 2024; 121 responded (44.2%). Respondents included HBOC carriers, healthcare professionals, and the general public. Among 66 carriers, 57 were affected and 9 were unaffected. Although the sample size is small, surveillance uptake was high among affected carriers (89.5%). Approximately half of affected carriers undergoing surveillance reported satisfaction, while nearly half underwent surveillance at multiple institutions, suggesting fragmented care. Across all groups including healthcare professionals and the general public, the most acceptable annual cost was less than 50,000 yen. Healthcare professionals identified interdepartmental coordination and shortages of genetic specialists as major challenges. These exploratory findings suggest that affordability, convenience, interdepartmental and interfacility coordination, and the availability of genetic medicine professionals may be important considerations in efforts to develop sustainable HBOC surveillance systems in Japan.