CD133+ cancer stem cell-like cells derived from uterine carcinosarcoma (malignant mixed Müllerian tumor).

Cancer stem cells (CSCs) that display tumor-initiating properties have recently been identified. CD133, a surface glycoprotein linked to organ-specific stem cells, has been described as a marker of CSCs in different tumor types. We herein identify and characterize CSCs in human uterine carcinosarcoma (malignant mixed Müllerian tumor), which is one of the most aggressive and therapy-resistant gynecological malignancies and is considered to be of mesodermal origin. The CD133(+) population was increased in uterine carcinosarcoma, and this population showed biphasic properties in the primary tumor. CD133(+) cells predominantly formed spheres in culture and were able to differentiate into mesenchymal lineages. CD133(+) cells were more resistant to cisplatin/paclitaxel-induced cytotoxicity in comparison with CD133(-) cells. A real-time polymerase chain reaction analysis of the genes implicated in stem cell maintenance revealed that CD133(+) cells express significantly higher levels of Oct4, Nanog, Sox2, and Bmi1 than CD133(-) cells. Moreover, CD133(+) cells showed a high expression level of Pax2 and Wnt4, which are genes essential for Müllerian duct formation. These CD133(+) cells form serially transplantable tumors in vivo and the resulting CD133(+) tumors replicated the EpCAM, vimentin, and estrogen and progesterone receptor expression of the parent tumor, indicating that CSCs likely differentiated into cells comprising the uterine carcinosarcoma tissue. Moreover, strong CD133 expression in both epithelial and mesenchymal elements in primary tumor demonstrated significant prognostic value. These findings suggest that CD133(+) cells have the characteristics of CSCs and Müllerian mesenchymal progenitors.

Metronomic doxifluridine chemotherapy combined with the anti-angiogenic agent TNP-470 inhibits the growth of human uterine carcinosarcoma xenografts.

Uterine carcinosarcoma is a highly aggressive gynecological neoplasm that responds poorly to conventional chemotherapy and radiotherapy. Metronomic chemotherapy is accepted as a new approach for cancer treatment, and its underlying mechanism seems to involve the suppression of angiogenesis. However, the efficacy of metronomic and anti-angiogenic therapies against uterine carcinosarcoma is unknown. The anti-angiogenic effect of doxifluridine was assessed in vitro using human umbilical vein endothelial cells (HUVEC) co-cultured with FU-MMT-1 human uterine carcinosarcoma cells. The antitumor and anti-angiogenic effects of metronomic doxifluridine (delivered via oral gavage) in combination with TNP-470 were evaluated in vivo. Tumor vascularity was assessed by contrast-enhanced color Doppler ultrasound, laser Doppler and microvessel density staining. Doxifluridine suppressed tube formation of HUVEC and vascular endothelial growth factor production by FU-MMT-1 cells. Metronomic doxifluridine alone significantly suppressed tumor growth compared with the untreated (control) group, while metronomic doxifluridine in combination with TNP-470 significantly inhibited tumor growth compared with each treatment alone. A significant reduction of intratumoral vascularity was observed in FU-MMT-1 xenografts following treatment with metronomic doxifluridine in combination with TNP-470, as compared with each treatment alone. Intestinal bleeding was only observed when the maximum tolerated dose of doxifluridine was administered in combination with TNP-470. Metronomic doxifluridine chemotherapy in combination with TNP-470 might be effective for uterine carcinosarcoma without marked toxicity, possibly acting via its potent anti-angiogenic effects. Clinical studies are needed to evaluate the safety and efficacy of this treatment in humans.

Metronomic irinotecan chemotherapy combined with ultrasound irradiation for a human uterine sarcoma xenograft.

Metronomic chemotherapy is the frequent administration of low doses of chemotherapeutic agents targeting tumor-associated endothelial cells. We examined the efficacy of metronomic irinotecan combined with low-intensity ultrasound (US) in human uterine sarcoma and evaluated its antiangiogenesis mechanism by measuring the circulating endothelial progenitor cells (CEP), a surrogate marker of angiogenesis. A human uterine sarcoma cell line, FU-MMT-3, was used in the present study because this tumor is one of the most malignant neoplasms of human solid tumors and it also has a high angiogenesis property. The combination of low-dose irinotecan and US irradiation significantly inhibited the tube formation of HUVEC and vascular endothelial growth factor expression of tumor cells in vitro. The FU-MMT-3 xenografts in nude mice were treated using US at a low intensity (2.0 w/cm(2), 1 MHz) for 4 min three times per week each after the intraperitoneal administration of irinotecan; this treatment was continued for 5 weeks. The tumor vascularity was assessed by contrast-enhanced color Doppler US in real time. The combination treatment significantly inhibited the mobilization of CEP and intratumoral vascularity compared with the control. This combination therapy showed a significant reduction in tumor volume, resulting in a significant prolongation of survival, in comparison with each treatment alone. These results suggest that the effect of metronomic chemotherapy for human uterine sarcoma was accelerated by US irradiation in vivo and this combination might therefore be potentially effective for new cancer therapy.

Novel chemoembolization using calcium-phosphate ceramic microsphere incorporating TNP-470, an anti-angiogenic agent.

The purpose of the present study was to develop a new method of chemoembolization to improve the therapeutic effectiveness and safety profile of cancer treatment. A chemoembolization approach was designed for human solid tumors using resorbable calcium-phosphate ceramic microspheres loaded with an agent anti-angiogenic to tumor vasculature in vivo. The human uterine sarcoma cell line FU-MMT-3 was used in this study because this tumor is aggressive and also exhibits a poor response to radiotherapy or any chemotherapy currently used. The calcium-phosphate ceramic microspheres loaded with TNP-470, an anti-angiogenic agent, were injected into FU-MMT-3 xenografts in nude mice three times per week for 8 weeks. The treatment using TNP-470-loaded microspheres suppressed tumor growth, compared to treatment with TNP-470 alone, microspheres alone, and the control. The mean tumor weight after treatment using TNP-470-loaded microspheres was significantly lower than that after treatment with microspheres alone. These ceramic microspheres were remarkably embolized in tumor microvessels as well as in the feeding arteries and a significant reduction of intratumoral vascularity was also demonstrated following treatment with TNP-470-loaded microspheres. Severe loss of body weight was not observed in any mice treated with the TNP-470-loaded microspheres, compared to treatment with TNP-470 alone. These results suggest that targeting tumor vasculature in human uterine sarcoma using calcium-phosphate microspheres might be more effective and safer than the treatment that employs anti-angiogenic agent alone. This new chemoembolization method incorporating an anti-angiogenic agent may contribute to the effective treatment of locally advanced or recurrent solid tumors.

The sonohysterographic difference in submucosal uterine fibroids and endometrial polyps treated by hysteroscopic surgery.

OBJECTIVE: The purpose of this study was to clarify the differences in sonohysterographic (SHG) findings between submucosal uterine fibroids and endometrial polyps treated by surgical hysteroscopy. METHODS: Eighty patients with intrauterine benign masses without any endometrial cytologic atypia were examined by SHG before undergoing surgical hysteroscopy. The SHG images in these masses were assessed for the following characteristics: size, number, location, echogenicity, and degree of projection into the uterine cavity. The SHG findings were then compared with their hysteroscopic findings. The feeding vessels into these masses were also assessed by transvaginal color Doppler sonography in 26 of the 80 patients. RESULTS: In all 80 patients, 47 histopathologically had submucosal fibroids, whereas the remaining 33 had endometrial polyps. Masses measuring greater than 20 mm were significantly more frequently fibroids than polyps (P < .01). Homogeneous hyperechoic masses were significantly seen in polyps (93.9% [31/33]; P < .01) but not in any fibroids except for 1 case. Multiple feeding vessels were significantly found in fibroids (12/15; P < .01), whereas they were not found in any of the 11 polyps examined. The location and degree of projection into the uterine cavity of these masses as assessed by SHG were consistent with their hysteroscopic findings in 78 (97.5%) of 80 patients. The foci of endometrial hyperplasia were significantly found in 5 (15.2%) of 33 polyps (P < .01), whereas no such tissues were obtained in any fibroids. CONCLUSIONS: Intracavitary fibroids tend to be larger than the polyps, and homogeneous hyperechoic masses in the uterine cavity observed by SHG are highly suggestive of endometrial polyps.