Ryo Tamura

Preoperative ultrasound-guided needle biopsy of 63 uterine tumors having high signal intensity upon T2-weighted magnetic resonance imaging.

Objective The differential diagnosis between uterine sarcoma and benign leiomyoma is difficult when made only by magnetic resonance imaging (MRI); it usually requires an additional preoperative diagnostic procedure. We report our results using ultrasound-guided needle biopsy for these types of uterine tumors. Methods Ultrasound-guided needle biopsy was performed on 63 patients with uterine smooth muscle tumors suspected of malignancy by MRI. We compared the results of presurgical biopsy against the postsurgical pathology of the tumor. Results Among 63 patients with a high signal intensity of the uterine tumor on T2-weighted MRI (1 case was undetermined), 12 cases (19.3%) were diagnosed by the needle biopsy as malignant, and 51 cases (80.6%) were benign. Among the 12 diagnosed as malignant tumors, 11 had surgery performed, and one was treated with chemotherapy. Among the 51 patients diagnosed with a benign tumor, 27 had surgery performed, and 24 were put on a wait-and-see clinical follow-up schedule. One of the 27 surgical patients with a benign tumor had a postsurgical diagnosis of a low-grade endometrial stromal sarcoma. In the 38 cases where surgery was performed, we found the sensitivity, specificity, and the positive and negative predictive values of the needle biopsy were 91.7%, 100%, 100%, and 96.2%, respectively. Conclusions Ultrasound-guided needle biopsy may be a reliable preoperative diagnostic procedure for uterine tumors with suspected malignancy.

Novel therapeutic strategy for cervical cancer harboring FGFR3-TACC3 fusions

We previously found that therapeutic targetable fusions are detected across various cancers. To identify therapeutic targetable fusion in uterine cervical cancer, for which no effective gene targeted therapy has yet been clinically applied, we analyzed RNA sequencing data from 306 cervical cancer samples. We detected 445 high confidence fusion transcripts and identified four samples that harbored FGFR3-TACC3 fusion as an attractive therapeutic target. The frequency of FGFR3-TACC3-fusion-positive cervical cancer is also 1.9% (2/103) in an independent cohort. Continuous expression of the FGFR3-TACC3 fusion transcript and protein induced anchorage-independent growth in the cervical epithelial cell line established from the ectocervix (Ect1/E6E7) but not in that from endocervix (End1/E6E7). Injection of FGFR3-TACC3 fusion-transfected-Ect1/E6E7 cells subcutaneously into NOG mice generated squamous cell carcinoma xenograft tumors, suggesting the association between FGFR3-TACC3 fusion and squamous cell carcinogenesis. Transfection of a FGFR3-TACC3 fusion transcript into four cervical cancer cell lines (SiHa, ME180, HeLa, and Ca Ski) induced activation of the MAPK pathway and enhancement of cell proliferation. Transcriptome analysis of the FGFR3-TACC3 fusion-transfected cell lines revealed that an IL8-triggered inflammatory response was increased, via activation of FGFR3–MAPK signaling. Continuous expression of FGFR3-TACC3 fusion led to activation of the PI3K–AKT pathway only in the two cell lines that harbored PIK3CA mutations. Sensitivity to the FGFR inhibitor, BGJ398, was found to depend on PIK3CA mutation status. Dual inhibition of both FGFR and AKT showed an obvious synergistic effect in cell lines that harbor mutant PIK3CA. Additionally, TACC3 inhibitor, KHS101, suppressed FGFR3-TACC3 fusion protein expression and showed antitumor effect against FGFR3-TACC3 fusion-transfected cell lines. FGFR3-TACC3 fusion-positive cancer has frequent genetic alterations of the PI3K/AKT pathway and selection of appropriate treatment based on PI3K/AKT pathway status should be required.

Sox2-dependent inhibition of p21 is associated with poor prognosis of endometrial cancer

Sex‐determining region Y‐box 2 (SOX2) is an essential factor involved in the self‐renewal and pluripotency of embryonic stem cells and has functions in cell survival and progression in many types of cancers. Here, we found that several endometrial cancer cell lines expressed SOX2, which was required for cell growth. Additionally, SOX2 overexpression regulated the expression of cyclin‐dependent kinase inhibitor 1A (CDKN1A), and SOX2 specifically bound to p21 promoter DNA in endometrial cancer cell lines expressing SOX2. Expressions of SOX2 in endometrial cancer patients were significantly correlated with histological grade and poor prognosis. Moreover, low p21 together with high SOX2 expressions in advanced endometrial cancer patients were associated with the most unfavorable outcomes of patients. These results indicated that simultaneous measurement of SOX2 and p21 expression in endometrial cancer patients may be a useful biomarker for patient prognosis.

Effectiveness of the cyclic administration of dienogest in a case of pathological disappearance of intestinal endometriosis.

We have reported good control of atypical genital bleeding when using a cyclic administration of dienogest (repeated 4-week cycles, each consisting of the administration of 2 mg/day of dienogest for 3 weeks, followed by 1 week of drug withdrawal) in patients with endometriosis. Herein, we report the effectiveness of the long-term cyclic administration (22 months) of dienogest in a case of pathological disappearance of intestinal endometriosis diagnosed by endoscopy and histology of the lower gastrointestinal tract. There is no recurrent sign after 16 months of the treatment being stopped. Atypical genital bleeding during treatment was 3–5 days a month in each cycle. Compliance was good, so we could continue the therapy. The long-term cyclic administration of dienogest in patients with intestinal endometriosis may have significant merit.

Novel kinase fusion transcripts found in endometrial cancer

Recent advances in RNA-sequencing technology have enabled the discovery of gene fusion transcripts in the transcriptome of cancer cells. However, it remains difficult to differentiate the therapeutically targetable fusions from passenger events. We have analyzed RNA-sequencing data and DNA copy number data from 25 endometrial cancer cell lines to identify potential therapeutically targetable fusion transcripts, and have identified 124 high-confidence fusion transcripts, of which 69% are associated with gene amplifications. As targetable fusion candidates, we focused on three in-frame kinase fusion transcripts that retain a kinase domain (CPQ-PRKDC, CAPZA2-MET, and VGLL4-PRKG1). We detected only CPQ-PRKDC fusion transcript in three of 122 primary endometrial cancer tissues. Cell proliferation of the fusion-positive cell line was inhibited by knocking down the expression of wild-type PRKDC but not by blocking the CPQ-PRKDC fusion transcript expression. Quantitative real-time RT-PCR demonstrated that the expression of the CPQ-PRKDC fusion transcript was significantly lower than that of wild-type PRKDC, corresponding to a low transcript allele fraction of this fusion, based on RNA-sequencing read counts. In endometrial cancers, the CPQ-PRKDC fusion transcript may be a passenger aberration related to gene amplification. Our findings suggest that transcript allele fraction is a useful predictor to find bona-fide therapeutic-targetable fusion transcripts.

Ectopic pregnancy following oral levonorgestrel emergency contraception use: Ectopic after emergency contraception

Levonorgestrel is used worldwide as an emergency oral contraceptive. There have been occasional reports of ectopic pregnancy after oral levonorgestrel use. We present a case of ectopic tubal pregnancy after the use of oral levonorgestrel as an emergency contraceptive in a 37‐year‐old woman with a history of treatment for Chlamydia trachomatis infection. She conceived after sexual intercourse on menstrual day 14 of the first menstrual cycle following a normal delivery. After salpingectomy for this right tubal pregnancy, her following pregnancy was an ectopic pregnancy in the contralateral tube, which was treated with laparoscopic salpingectomy. Histopathological examination revealed endometriosis. We should be aware of ectopic pregnancy even after emergency contraceptive use, especially in patients with risk factors, such as Chlamydia infection and endometriosis. Because the efficacy of levonorgestrel decreases after ovulation, we should check the stage of the cycle before prescription.

Novel MXD4-NUTM1 fusion transcript identified in primary ovarian undifferentiated small round cell sarcoma

Primary ovarian sarcomas are extremely rare tumors, and their genomic and transcriptomic alterations remain to be elucidated. We performed whole exome sequencing of primary tumor and matched normal blood samples derived from one patient with ovarian undifferentiated small round cell sarcoma. We identified 8 nonsynonymous somatic mutations, and all mutations were missense or nonsense changes. Next, we performed RNA sequencing of the tumor sample and identified two in‐frame fusion transcripts: MXD4–NUTM1 and ARL6–POT1. Most NUTM1 exons were retained in the MXD4–NUTM1 fusion transcript, and we confirmed an increase in NUTM1 mRNA and protein expression in tumor tissue. Further genomic and transcriptomic analyses might lead to the development of new therapeutic strategies based on the molecular characteristics of ovarian undifferentiated small round cell sarcoma.