Akiko Tozawa

Pathogenesis of Hand-Foot Syndrome induced by PEG-modified liposomal Doxorubicin

PEGL-DOX is an excellent treatment for recurrent ovarian cancer that rarely causes side-effects like cardiotoxicity or hair loss, but frequently results in Hand-Foot Syndrome (HFS). In severe cases, it can become necessary to reduce the PEGL-DOX concentration or the duration of the drug therapy, sometimes making it difficult to continue treatment. In this study, we prepared an animal model to compare the effects of DOX versus PEGL-DOX, and we noticed that only treatment with PEGL-DOX resulted in HFS, which led us to conclude that extravasation due to long-term circulation was one of the causes of HFS. In addition, we were able to show that the primary factor leading to the skin-specific outbreaks in the extremities was the appearance of reactive oxygen species (ROS) due to interactions between DOX and the metallic Cu(II) ions abundant in skin tissue. ROS directly disturb the surrounding tissue and simultaneously induce keratinocyte-specific apoptosis. Keratinocytes express the thermoreceptor TRPM2, which is thought to be able to detect ROS and stimulate the release of chemokines (IL-8, GRO, Fractalkine), which induce directed chemotaxis in neutrophils and other blood cells. Those cells and the keratinocytes then undergo apoptosis and simultaneously release IL-1β, IL-1α, and IL-6, which brings about an inflammatory state. In the future, we plan to develop preventative as well as therapeutic treatments by trapping the ROS.

Transcription factor POU6F1 is important for proliferation of clear cell adenocarcinoma of the ovary and is a potential new molecular target.

Objective: Clear cell adenocarcinoma of the ovary often shows resistance to anticancer agents. It accounts for 20% of epithelial ovarian cancer in Japan versus around 5% in other countries. We investigated new molecules to use when developing molecular-targeting therapy for clear cell adenocarcinoma. Methods: Reverse transcriptase polymerase chain reaction and Western blot analysis were performed to confirm the expression of POU6F1 in several kinds of cell lines derived from epithelial ovarian carcinoma. Microarray analyses were performed using 2 ovarian cancer microarray data sets available on the Internet. Immunohistochemical staining was also done to confirm both the expression and the localization of POU6F1 using human ovarian epithelial ovarian carcinoma tissue specimens. In addition, the gene cluster located downstream of transcription factor POU6F1 was investigated to analyze its role in the proliferation of clear cell adenocarcinoma of the ovary via the lysophosphatidic acid receptor, a G protein-coupled receptor. Furthermore, RNA interference studies with small interfering RNA (siRNA) were performed to assess the effect of POU6F1 on proliferation of xenograft tumors after injection of clear cell adenocarcinoma cells into nude mice. Results: Expression of POU6F1 at messenger RNA and protein was confirmed in cell lines derived from epithelial ovarian carcinoma. The microarray analyses performed using the 2 ovarian cancer microarray data sets available on the Internet indicated that POU6F1 expression was significantly greater in clear cell adenocarcinoma. Immunostaining confirmed the nuclear localization of POU6F1 in clear cell adenocarcinoma (100%). Exposure to the siRNA for POU6F1 reduced the expression of lysophosphatidic acid receptors, which are G protein-coupled receptors involved in tumor cell proliferation. POU6F1 siRNA dose-dependently suppressed the proliferation of clear cell adenocarcinoma cell lines, and a similar effect was confirmed for tumors transplanted into nude mice. Conclusions: Clear cell adenocarcinoma shows little response to standard therapy. The results of this study suggested that the transcription factor POU6F1 could be a new molecular target for treatment of this cancer.

Complete remission with intraperitoneal cisplatin followed by prolonged oral etoposide in a stage IIIc primary leiomyosarcoma of the fallopian tube patient

Leiomyosarcoma (LMS) of the fallopian tube is exceedingly uncommon. So far as we investigated, only eighteen cases of LMS of the fallopian tube have been reported. Here we report a nineteenth case which was International Federation of Gynecology and Obstetrics stage IIIc LMS of the fallopian tube successfully treated with intraperitoneal cisplatin followed by prolonged oral etoposide. A 70‐year‐old female was introduced to our institute due to intrapelvic tumor and ascites. Because of elevated serum lactate dehydrogenase and CA125 as well as the findings of pelvic magnetic resonance imaging and computerized tomography, the patient was suspected to have ovarian cancer. In laparotomy, the large pelvic tumor was seemed to originate from the right fallopian tube. Pathologically, the patient was diagnosed as stage IIIc fallopian tube LMS. At the end of the operation, cisplatin was given intraperitoneally followed by prolonged oral etoposide. Although a lot of dissemination was noted throughout the peritoneal cavity, the patient is alive without any evidence of recurrence for more than 6 years since the initial operation. In this uncommon entity, a cisplatin‐ and etoposide‐based regimen could be considered.

Oocyte retrieval after heterotopic transplantation of ovarian tissue cryopreserved by closed vitrification protocol

PurposeA device for closed vitrification was designed to reduce the risk of contamination and investigated on its efficacy for ovarian function recovery after cryopreservation and heterotopic transplantation.MethodsOvarian tissues from green fluorescence protein transgenic mice (10 GFP mice) were vitrified using the device, and warmed ovarian tissues were transplanted into the ovarian bursa region in wild-type female mice (6 mice). Fresh ovarian tissues were similarly transplanted as a control. After recovery of the estrous cycle, mice were mated with male mice. Ovarian tissues from six cynomolgus monkeys were vitrified and warmed with the device for autologous, heterotopic transplantation. Fresh tissue transplantation was not performed for the control. Ovarian function was examined by recovery of the hormonal cycle. Histological examination was conducted.ResultsThe number of live pups per recipient mouse was not significantly different after transplantation of fresh or vitrified-warmed ovarian tissue, although the pregnancy rate was reduced with vitrified tissues. The hormonal cycle was restored in 5/6 monkeys after heterotopic transplantation of vitrified-warmed ovarian tissue. Follicles were harvested at eight sites in the omentum and 13 sites in the mesosalpinx. In vitro maturation (IVM)/IVF produced embryo but did not develop.ConclusionsResumption of the hormonal cycles, follicle development, and oocyte retrieval from vitrified-warmed ovarian tissue transplants may indicate that the use of vitrification for ovarian tissue in a closed system has a potential of clinical application without the risk of contaminations. More detailed analyses of the effects of vitrification on ovarian tissue, such as gene expression patterns in oocytes and granulosa cells, may be needed for establishing a standard procedure for cryopreservation of ovarian tissues in human.

Sonohysterography in a suspected case of uterine perforation after dilatation and curettage for retained placenta

Abstract A 35-year-old woman, gravida 3, para 2, spontaneously delivered an infant without any major complications. On the 38th day after delivery, she returned to the hospital due to irregular bleeding. Transvaginal ultrasound showed a mass in the cervix; therefore, dilatation and curettage was performed, using placental forceps, to remove the retained placenta. During the procedure, a uterine perforation was suspected. Sonohysterography was performed in order to confirm the uterine perforation. The sonohysterogram revealed that the high echogenic mass that was suspected to be retained placenta was adhered on the posterior uterine myometrium. Saline that had been injected into the uterine cavity escaped into the Douglas pouch via a small hole in the posterior uterine wall. An emergency laparotomy was performed. Pathological examination of the removed uterus revealed placenta increta in the posterior wall, as well as an adjacent perforated fistula. Sonohysterographic diagnosis of uterine perforation in the present case was not only validated with diagnosis, but also the residual placenta was clearly visible. The use of sonohysterography for detection of a suspected case of uterine perforation after dilatation and curettage was accurate and provided a safe procedure for fast evaluation.