Tsutomu Miyamoto

Ligand‐Based CAR‐T Cells Targeting EGFR Exhibit Favorable Antitumor Effects Against Gynecologic Malignancies

ABSTRACTEpidermal growth factor receptor (EGFR) has been reported to be overexpressed in gynecologic malignancies. However, the clinical efficacy of existing molecular EGFR‐targeted therapies against gynecologic malignancies has not been demonstrated. In this study, we investigated the antitumor effects of ligand‐based EGFR chimeric antigen receptor (CAR)‐T cells on gynecologic malignancies. First, we evaluated EGFR expression in patient samples using immunohistochemistry. EGFR positivity was observed in 41%, 82%, and 79% of ovarian, endometrial, and cervical cancer in patient samples, respectively. Second, we generated ligand‐based EGFR CAR‐T cells via piggyBac‐mediated gene transfer. EGFR CAR‐T cells were successfully generated with high CAR positivity and a high proportion of naïve/stem cell memory‐like T cells. Finally, we investigated the antitumor effects of EGFR CAR‐T cells on gynecologic malignancies. EGFR CAR‐T cells were co‐cultured with six EGFR‐positive gynecologic cancer cell lines. The growth of all six gynecologic cancer cell lines was significantly suppressed by EGFR CAR‐T cells compared to mock T cells. In in vivo studies, tumor‐bearing mice implanted with gynecologic cancer cell lines in their intraperitoneal cavity were administered EGFR CAR‐T cells, CD19 CAR‐T cells, or PBS intraperitoneally. Mice treated with EGFR CAR‐T cells displayed a significantly decreased tumor burden compared to those treated with either CD19 CAR‐T cells or PBS. Additionally, mice treated with EGFR CAR‐T cells had a significantly longer survival than the other groups. In summary, ligand‐based EGFR CAR‐T cells may be a promising therapy for various gynecologic malignancies.

Extensive Pathologic Invasion and Prognostic Implication of Gastric-Type Cervical Adenocarcinoma

Gastric-type adenocarcinoma (GAS) is the most common subtype of human papillomavirus (HPV)-independent cervical adenocarcinomas and is associated with a poor prognosis. We used a gross morphologic classification system and imaging analysis to compare the clinicopathological features of GAS and HPV-associated adenocarcinoma (HPVA) and identify factors contributing to the poor prognosis of GAS. This retrospective 2-center study analyzed 33 patients with GAS and 70 with HPVA (stages IB-IVB) who underwent surgery between 1997 and 2023. GAS had a higher rate of positive surgical margins (21.2% vs. 0%, respectively, P<0.001) and unclear tumor boundaries on gross morphologic findings (47.8% vs. 8.8%, respectively, P<0.001). Discrepancies between clinical and pathologic T classifications were more common in GAS, leading to frequent upstaging (51.5% vs. 28.6%, respectively, P=0.029). Imaging analysis revealed that GAS was associated with a smaller median tumor cell area (19.8% vs. 55.7%, respectively, P<0.001), which was significantly correlated with unclear tumor boundaries. Perineural invasion (PNI) was significantly more frequent in GAS (69.7% vs. 10.0%, respectively, P<0.001). A Kaplan-Meier analysis showed that patients with PNI had significantly poorer overall survival (P<0.001). A Cox multivariate analysis identified an advanced pathologic stage, positive peritoneal cytology, and positive surgical margins as independent risk factors. The present results indicate that GAS has a unique “stealth” invasion pattern, possibly caused by low tumor density, leading to undetectable tumor boundaries and positive surgical margins. This suggests a greater risk of incomplete resection than HPVA, leading to a poorer prognosis.

Problems of magnetic resonance diagnosis for gastric-type mucin-positive cervical lesions of the uterus and its solutions using artificial intelligence

Purpose To reveal problems of magnetic resonance imaging (MRI) for diagnosing gastric-type mucin-positive (GMPLs) and gastric-type mucin-negative (GMNLs) cervical lesions. Methods We selected 172 patients suspected to have lobular endocervical glandular hyperplasia; their pelvic MR images were categorised into the training (n = 132) and validation (n = 40) groups. The images of the validation group were read twice by three pairs of six readers to reveal the accuracy, area under the curve (AUC), and intraclass correlation coefficient (ICC). The readers evaluated three images (sagittal T2-weighted image [T2WI], axial T2WI, and axial T1-weighted image [T1WI]) in every patient. The pre-trained convolutional neural network (pCNN) was used to differentiate between GMPLs and GMNLs and perform four-fold cross-validation using cases in the training group. The accuracy and AUC were obtained using the MR images in the validation group. For each case, three images (sagittal T2WI and axial T2WI/T1WI) were entered into the CNN. Calculations were performed twice independently. ICC (2,1) between first- and second-time CNN was evaluated, and these results were compared with those of readers. Results The highest accuracy of readers was 77.50%. The highest ICC (1,1) between a pair of readers was 0.750. All ICC (2,1) values were <0.7, indicating poor agreement; the highest accuracy of CNN was 82.50%. The AUC did not differ significantly between the CNN and readers. The ICC (2,1) of CNN was 0.965. Conclusions Variation in the inter-reader or intra-reader accuracy in MRI diagnosis limits differentiation between GMPL and GMNL. CNN is nearly as accurate as readers but improves the reproducibility of diagnosis.

cDNA expression library screening revealed novel functional genes involved in clear cell carcinogenesis of the ovary in vitro

In order to identify genes involved in the pathogenesis of clear cell carcinoma of the ovary (CCC), functional screening using a cDNA expression library was performed. We extracted mRNA from a CCC cell line (RMG-1), established a cDNA library using a retroviral vector, transfected that library into mouse NIH3T3 cells and sequenced the resultant foci. The tissue-type specific expression of isolated genes and their transforming activities were evaluated. Seven genes were isolated. Of these genes, the mRNA expression of SEC61B and DVL1 is significantly stronger in CCC than in other histological types (

Limited frequency of malignant change in lobular endocervical glandular hyperplasia

Although lobular endocervical glandular hyperplasia is a benign disorder of the uterine cervix, its potential as a precursor of minimal deviation adenocarcinoma has been reported. However, the natural history of the disease and the frequency of malignant change are not fully understood. We evaluated the frequency of malignant change of clinical lobular endocervical glandular hyperplasia and explored useful parameters indicating malignant change. The clinical courses of 175 patients with cervical multi-cystic lesions who visited Shinshu University Hospital between June 1995 and June 2019 were retrospectively analyzed. We examined the results of follow-up and outcomes of the patients diagnosed with lobular endocervical glandular hyperplasia and investigated the frequency of malignant transformation. Of the 175 patients, 15, 84, and 76 were clinically diagnosed with suspected malignancy, suspected lobular endocervical glandular hyperplasia, and suspected nabothian cyst, respectively. Of these patients, 69 patients with suspected lobular endocervical glandular hyperplasia were followed, and 12 underwent hysterectomy after a mean follow-up of 57.1 (range: 3-154) months due to lesion enlargement (increase in tumor diameter of >20%) and/or worsening cytology. Of these 12 patients, two had lobular endocervical glandular hyperplasia with atypia and one had minimal deviation adenocarcinoma. Of 69 patients, the rate of malignant change was 1.4% (1/69). The growth rates of the lesions for these three patients during follow-up were significantly higher than those of nine patients who underwent surgery with lobular endocervical glandular hyperplasia without atypia and 48 follow-up cases of suspected lobular endocervical glandular hyperplasia. The cut-off value of the growth rate suggesting malignant transformation was 38.1% (84.6% sensitivity and 100% specificity). Tumor size and cytology did not change in the remaining 57 cases continuing follow-up. An increase in tumor size and worsening cytology are important parameters for detecting malignant transformation of lobular endocervical glandular hyperplasia during follow-up. However, the frequency of malignant change of this disease may be limited. These results suggest that conservative management may be an option for clinical lobular endocervical glandular hyperplasia.

Biology and management of lobular endocervical glandular hyperplasia

AbstractAimLobular endocervical glandular hyperplasia (LEGH) is a multicystic proliferative disorder of the uterine cervix. The aim of this review was to clarify the current understanding of this unique tumor.MethodThis article reviews the chronological progress of research regarding clinico‐pathological and genetic aspects of LEGH and related cervical cystic diseases such as Nabothian cyst and adenocarcinoma of gastric type (GAS), using the literature and data from our institute. We also describe clinical management including preoperative diagnosis and adequate surgical/expectant treatment based on the biological features.ResultsRecent studies revealed several unique aspects of LEGH, that is, (i) production of gastric mucin, (ii) symptomatic and histological similarity with minimal deviation adenocarcinoma (MDA), and (iii) frequent association with GAS, including MDA. These findings indicated that LEGH is a gastric metaplasia, as well as pre‐cancerous neoplasia. For the preoperative diagnosis of LEGH, the combination of “cosmos” sign on magnetic resonance imaging, detection of gastric mucin, and lack of nuclear atypia on cytology is important. Cone biopsy is effective for pathological diagnosis. Simple hysterectomy is indicated as surgical treatment for LEGH; however, meticulous follow‐up is also an option, especially for young patients, because the rate of malignant transformation was reported to be 1%–2%. For LEGH patients who selected follow‐up, a worsening cytology and increase in lesion size were important signs of malignant change of LEGH for safe follow‐up.ConclusionProper understanding of the characteristics of LEGH is important for adequate management.