Multidirectional Traction Method Using SURGICEL NU-KNIT and Surgical Suture in Robot-assisted Laparoscopic Surgery for Endometrial Cancer.

OBJECTIVE: To describe a novel approach to robot-assisted laparoscopic total hysterectomy (RH) for endometrial cancer that minimizes cancer sell spillage and develops a stable surgical field. DESIGN: Demonstration of the multidirectional traction method with narrated video footage. SETTING: Many reports have indicated that RH for endometrial cancer has the same or superior short-term results compared with conventional laparoscopic hysterectomy (LH), and the long-term prognosis is the same [1,2]. However, there are no randomized controlled trials of RH versus LH, and some previous reports [3] have suggested that RH has a worse prognosis than LH, so the long-term prognosis should be considered with caution. Factors that may affect the long-term prognosis include the use of uterine manipulators [4] and compression of the uterine body with robotic forceps without tactile sensation [3]. However, to the best of our knowledge, no surgical technique capable of avoiding these factors has been established yet. Herein, we report a multidirectional traction method using SURGICEL NU-KNIT (Ethicon; Johnson & Johnson Medical Ltd., Tokyo, Japan), a local hemostatic agent, and surgical sutures. INTERVENTION: Cut 2-0 Prolene (Ethicon; Johnson & Johnson Medical Ltd., Tokyo, Japan) with straight needles (ST-70) thread to 35 cm, stick a 1 × 2 cm piece of SURGICEL NU-KNIT, and make knots Fig. 1. This implement is used to puncture the incisional margins of the peritoneum and then the abdominal wall to bring the thread to the surface of the body, where it is grasped with forceps and fixed. By repeating this operation, multidirectional traction can be obtained Fig. 2. A manipulating suture is also attached to the uterus to minimize the compression of the uterine body with robotic forceps. CONCLUSION: The multidirectional traction method allows for reproducible stable surgical field development and minimizes cancer cell spillage by reducing uterine grasping by robotic forceps without the use of uterine manipulators.

Effect of murine double-minute 2 inhibitors in preclinical models of advanced clear cell carcinomas originating from ovaries and kidneys.

Advanced clear cell carcinomas originating from both ovaries and kidneys with cancerous peritonitis have poor prognoses. Murine double-minute 2 (MDM2) is a potential therapeutic target for clear cell ovarian carcinomas with WT TP53. Herein, we characterized the antiangiogenic and antitumor effects of the MDM2 inhibitors DS-3032b and DS-5272 in 6 clear cell ovarian carcinoma cell lines and 2 clear cell renal carcinoma cell lines, as well as in clear cell ovarian carcinomas s.c. xenograft and ID8 (murine ovarian cancer cells with WT TP53) cancer peritonitis mouse models. In clear cell ovarian carcinoma s.c. xenograft mouse models, DS-3032b significantly reduced WT TP53 clear cell ovarian carcinoma- and clear cell renal carcinoma-derived tumor volumes. In ID8 mouse models, DS-5272 significantly inhibited ascites production, reduced body weight, and significantly improved overall survival. Additionally, DS-5272 reduced the tumor burden of peritoneal dissemination and decreased CD31+ cells in a dose-dependent manner. Furthermore, DS-5272 significantly decreased vascular endothelial growth factor concentrations in both sera and ascites. Combined therapy with MDM2 inhibitors and everolimus showed synergistic, and dose-reduction potential, for clear cell carcinoma treatment. Our findings suggest that MDM2 inhibitors represent promising molecular targeted therapy for clear cell carcinomas, thereby warranting further studies to evaluate the efficacy and safety of dual MDM2/mTOR inhibitors in clear cell carcinoma patients.

Histone methyltransferase SMYD2 selective inhibitor LLY-507 in combination with poly ADP ribose polymerase inhibitor has therapeutic potential against high-grade serous ovarian carcinomas.

Dysfunction of histone methylation is known to be related to cancer progression. The histone methyltransferase SMYD2 methylates histone protein H3 and non-histone proteins, including poly ADP ribose polymerase 1 (PARP1). There have been reports of SMYD2 overexpression in several types of cancers. However, there are no reports regarding its role in high-grade serous ovarian carcinomas (HGSOCs). Therefore, we investigated the expression profile and conducted functional analysis on SMYD2 in HGSOC cells. In addition, we verified whether SMYD2 inhibition increases the susceptibility of HGSOC cells to PARP inhibitors. We analyzed the expression of histone methyltransferase SMYD2 by quantitative real-time polymerase chain reaction and immunohistochemistry using HGSOC clinical tissues (n = 35). We performed functional analyses, including cell proliferation assay, cell cycle analysis, and immunoblotting, after treatment with SMYD2 siRNAs and SMYD2 selective inhibitor LLY-507 in HGSOC cells. We also performed colony-formation assay after combination treatment with LLY-507 and PARP inhibitor olaparib in HGSOC cells. The expression profiles of SMYD2 showed significant overexpression of SMYD2 in HGSOC clinical tissues. The knockdown or inhibition of SMYD2 by siRNAs or LLY-507, respectively, suppressed cell growth by increasing the proportion of apoptotic cells. LLY-507 showed additive effect with olaparib in the colony-formation assay. These findings suggest that LLY-507 can be used alone or in combination with a PARP inhibitor for the treatment of patients with HGSOC.

The histone methyltransferase WHSC1 is regulated by EZH2 and is important for ovarian clear cell carcinoma cell proliferation.

BACKGROUND: Wolf-Hirschhorn syndrome candidate gene-1 (WHSC1), a histone methyltransferase, has been found to be upregulated and its expression to be correlated with expression of enhancer of zeste homolog 2 (EZH2) in several cancers. In this study, we evaluated the role of WHSC1 and its therapeutic significance in ovarian clear cell carcinoma (OCCC). METHODS: First, we analyzed WHSC1 expression by quantitative PCR and immunohistochemistry using 23 clinical OCCC specimens. Second, the involvement of WHSC1 in OCCC cell proliferation was evaluated by MTT assays after siRNA-mediated WHSC1 knockdown. We also performed flow cytometry (FACS) to address the effect of WHSC1 on cell cycle. To examine the functional relationship between EZH2 and WHSC1, we knocked down EZH2 using siRNAs and checked the expression levels of WHSC1 and its histone mark H3K36m2 in OCCC cell lines. Finally, we checked WHSC1 expression after treatment with the selective inhibitor, GSK126. RESULTS: Both quantitative PCR and immunohistochemical analysis revealed that WHSC1 was significantly overexpressed in OCCC tissues compared with that in normal ovarian tissues. MTT assay revealed that knockdown of WHSC1 suppressed cell proliferation, and H3K36me2 levels were found to be decreased in immunoblotting. FACS revealed that WHSC1 knockdown affected the cell cycle. We also confirmed that WHSC1 expression was suppressed by EZH2 knockdown or inhibition, indicating that EZH2 is upstream of WHSC1 in OCCC cells. CONCLUSIONS: WHSC1 overexpression induced cell growth and its expression is, at least in part, regulated by EZH2. Further functional analysis will reveal whether WHSC1 is a promising therapeutic target for OCCC.

The Histone Methyltransferase SETD8 Regulates the Expression of Tumor Suppressor Genes via H4K20 Methylation and the p53 Signaling Pathway in Endometrial Cancer Cells.

The histone methyltransferase SET domain-containing protein 8 (SETD8), which methylates histone H4 lysine 20 (H4K20) and non-histone proteins such as p53, plays key roles in human carcinogenesis. Our aim was to determine the involvement of SETD8 in endometrial cancer and its therapeutic potential and identify the downstream genes regulated by SETD8 via H4K20 methylation and the p53 signaling pathway. We examined the expression profile of SETD8 and evaluated whether SETD8 plays a critical role in the proliferation of endometrial cancer cells using small interfering RNAs (siRNAs). We identified the prognostically important genes regulated by SETD8 via H4K20 methylation and p53 signaling using chromatin immunoprecipitation sequencing, RNA sequencing, and machine learning. We confirmed that SETD8 expression was elevated in endometrial cancer tissues. Our in vitro results suggest that the suppression of SETD8 using siRNA or a selective inhibitor attenuated cell proliferation and promoted the apoptosis of endometrial cancer cells. In these cells, SETD8 regulates genes via H4K20 methylation and the p53 signaling pathway. We also identified the prognostically important genes related to apoptosis, such as those encoding KIAA1324 and TP73, in endometrial cancer. SETD8 is an important gene for carcinogenesis and progression of endometrial cancer via H4K20 methylation.

The histone methyltransferase SMYD2 is a novel therapeutic target for the induction of apoptosis in ovarian clear cell carcinoma cells.

Previous studies have suggested that histone methylation can modulate carcinogenesis and cancer progression. For instance, the histone methyltransferase SET and MYND domain containing 2 (SMYD2) is overexpressed in several types of cancer tissue. The aim of the present study was to determine whether SMYD2 could serve a therapeutic role in ovarian clear cell carcinoma (OCCC). Reverse transcription-quantitative PCR was used to examine SMYD2 expression in 23 clinical OCCC specimens. Moreover, OCCC cell proliferation and cell cycle progression were also examined following small interfering RNA-mediated SMYD2 silencing or treatment with a selective SMYD2 inhibitor. SMYD2 was significantly upregulated in clinical OCCC specimens, compared with normal ovarian tissue. In addition, SMYD2 knockdown decreased cell viability as determined via a Cell Counting Kit-8 assay. Moreover, the proportion of cells in the sub-G1 phase increased following SMYD2 knockdown, suggesting increased apoptosis. Treatment with the SMYD2 inhibitor LLY-507 suppressed OCCC cell viability. These results suggested that SMYD2 could promote OCCC viability, and that SMYD2 inhibition induced apoptosis in these cells. Thus, SMYD2 inhibitors may represent a promising molecular targeted approach for OCCC treatment.

Epigenetic Modifier SETD8 as a Therapeutic Target for High-Grade Serous Ovarian Cancer.

The histone methyltransferase SETD8, which methylates the lysine 20 of histone H4 (H4K20), is reportedly involved in human carcinogenesis along with nonhistone proteins such as p53. However, its expression profiles and functions in the context of high-grade serous ovarian carcinoma (HGSOC) are still unknown. The purpose of this study was to investigate the role of SETD8 in HGSOC. We performed quantitative real-time PCR and immunohistochemistry to detect the expression of SETD8 in HGSOC samples and normal ovarian specimens. Then, we assessed the effect of the inhibition of SETD8 expression using small interfering RNA (siRNA) and a selective inhibitor (UNC0379) on cell proliferation and apoptosis in HGSOC cells. The expression of SETD8 was significantly upregulated in clinical ovarian cancer specimens compared to that in the corresponding normal ovary. In addition, suppression of SETD8 expression in HGSOC cells with either siRNA or UNC0379 resulted in reduced levels of H4K20 monomethylation, inhibition of cell proliferation, and induction of apoptosis. Furthermore, UNC0379 showed a long-term antitumor effect against HGSOC cells, as demonstrated by colony-formation assays. SETD8 thus constitutes a promising therapeutic target for HGSOC, warranting further functional studies.

Kaempferol, a natural dietary flavonoid, suppresses 17ß-estradiol-induced survivin expression and causes apoptotic cell death in endometrial cancer.

Endometrioid endometrial carcinoma, commonly known as type 1 endometrial cancer, accounts for >80% of endometrial carcinomas and is dependent on estrogen. We recently reported on the prognostic significance of the BIRC5 survivin gene in endometrial cancer. Estradiol induces survivin expression in estrogen receptor-positive, but not in estrogen receptor-negative, cancer cells. Kaempferol, a bioflavonoid, reportedly inhibits estrogen receptor-α (ERα) in hormone receptor-positive breast cancer cells. However, whether kaempferol-mediated inhibition of ERα suppresses survivin and induces cell death in endometrial cancer remains unclarified. The present study evaluated the antitumor effects of kaempferol on endometrial cancer cells. Cell viability assays, flow cytometry analysis, western blotting and annexin V analyses were used to analyze the antitumor effects of kaempferol. The results demonstrated that kaempferol successfully suppressed the viability of two ER-positive endometrial cancer cell lines, with IC50 values of 83 and 65 µM. In addition, kaempferol induced sub-G1 cell accumulation and apoptotic cell death (P<0.01) in a dose-dependent manner. Treatment of cells with estradiol significantly induced co-expression of nuclear ERα and survivin proteins (P<0.001). Further evaluation revealed that kaempferol causes apoptotic cell death largely by suppressing ERα, survivin and Bcl-2 protein. Therefore, the results of the present study suggested that targeting ERα and survivin with kaempferol may be a novel therapeutic option against endometrial carcinoma.

MDM2 is a potential therapeutic target and prognostic factor for ovarian clear cell carcinomas with wild type TP53.

MDM2, a ubiquitin ligase, suppresses wild type TP53 via proteasome-mediated degradation. We evaluated the prognostic and therapeutic value of MDM2 in ovarian clear cell carcinoma. MDM2 expression in ovarian cancer tissues was analyzed by microarray and real-time PCR, and its relationship with prognosis was evaluated by Kaplan-Meier method and log-rank test. The anti-tumor activities of MDM2 siRNA and the MDM2 inhibitor RG7112 were assessed by cell viability assay, western blotting, and flow cytometry. The anti-tumor effects of RG7112 in vivo were examined in a mouse xenograft model. MDM2 expression was significantly higher in clear cell carcinoma than in ovarian high-grade serous carcinoma (P = 0.0092) and normal tissues (P = 0.035). High MDM2 expression determined by microarray was significantly associated with poor progression-free survival and poor overall survival (P = 0.0002, and P = 0.0008, respectively). Notably, RG7112 significantly suppressed cell viability in clear cell carcinoma cell lines with wild type TP53. RG7112 also strongly induced apoptosis, increased TP53 phosphorylation, and stimulated expression of the proapoptotic protein PUMA. Similarly, siRNA knockdown of MDM2 induced apoptosis. Finally, RG7112 significantly reduced the tumor volume of xenografted RMG-I clear cell carcinoma cells (P = 0.033), and the density of microvessels (P = 0.011). Our results highlight the prognostic value of MDM2 expression in clear cell carcinoma. Thus, MDM2 inhibitors such as RG7112 may constitute a class of potential therapeutics.