High-risk human papillomavirus (HPV) is a common cause of cervical cancer. HPV E6 oncoprotein promotes the degradation of host tumor suppressor gene p53, leading to the development of tumors. Therapeutic strategies that specifically target E6, which is constitutively expressed in tumors and is not present in normal tissues, may be highly effective and safe. CRISPR-CRISPR associated protein 9 (Cas9) is one of the genome editing technologies that has recently garnered attention, and is used to knockout target gene expression. By combining cervical cancer cell lines engineered to constitutively express Cas9 and an adeno-associated virus (AAV) vector carrying a single guide (sg) RNA targeting E6 (AAV-sgE6), the present study sought to investigate the effects of this novel therapeutic approach on cervical cancer. The Cas9 gene was transfected into three high-risk HPV-positive cervical cancer cell lines (HeLa, HCS-2, and SKG-I) to establish cell lines that constitutively expressed Cas9. Using these cell lines, genetic mutations and their frequencies, as well as the levels of protein expression, apoptosis and cell proliferation were examined in vitro. In addition, the effects of AAV-sgE6 were examined in a mouse model of cervical cancer in vivo by a single administration of AAV-sgE6 directly into subcutaneous tumors. The results demonstrated that multiple mutations occurred frequently in the targeted E6 genomic sequence in cervical cancer cells transduced with AAV-sgE6. In addition, these AAV-sgE6-transduced cells had reduced expression of E6, increased expression of p53, increased apoptosis and their growth was suppressed in a concentration-dependent manner. Furthermore, subcutaneous tumor growth was significantly suppressed in vivo following intratumoral administration of AAV-sgE6, and adverse events due to AAV-sgE6 administration were not observed. Collectively, the present results indicated that targeting E6 expression in high-risk HPV by CRISPR-Cas9 is a highly specific and effective strategy that may be effective in treating patients with cervical cancer.

This study showed that the number of removed lymph nodes ≥ 35 was an independent predictor for improved RFS for stage I ovarian CCC. Sufficient lymphadenectomy may improve prognosis for stage I ovarian CCC.

There was no difference in the prognosis between the groups with and without symptoms at recurrence. Independent prognostic factors of recurrent patients were histopathologic types and RFS. A large-scale study should be conducted to examine the necessity of routine follow-up for detecting recurrence in the absence of symptoms.

ObjectiveTo establish new criteria for the omission of lymphadenectomy in patients with endometrioid carcinoma.Methods We retrospectively reviewed 185 cases of histologically confirmed endometrioid carcinoma by hysterectomy at Jichi Medical University Hospital between January 2006 and December 2011. We reviewed patient medical records to detect risk factors for lymph node metastasis to identify the optimum criteria for lymphadenectomy omission.ResultsUnivariate analysis revealed risk factors for lymph node metastasis to be a large tumor size (volume index ≥40 cm³) (p<0.0001), tumor diameter >2 cm (p=0.0003), myometrial invasion ≥50% based on pre-operative MRI (p=0.0366), elevated serum CA125 (pre-menopausal value ≥70 U/mL, post-menopausal value ≥25 U/mL) (p=0.0004), and lymphadenopathy on pre-operative CT scans (p=0.0002). Multivariate analysis indicated that tumor volume index, tumor diameter, elevated serum CA125, and CT scans positive for lymphadenopathy were independent risk factors for lymph node metastasis. Thus, we set tumor diameter >2 cm, elevated serum CA125, and CT scans positive for lymphadenopathy as risk factors. In cases with no risk factors, the rate of lymph node metastasis was 2.1%, which rose to 8.9%, 30.4%, and 58.3% for those with one, two, and three risk factors, respectively. The rate of para-aortic lymph node metastasis rose from 0% to 2.5%, 10.9%, and 41.7% among those with zero, one, two, and three risk factors, respectively.ConclusionsWe propose that lymphadenectomy can be omitted in cases of endometrioid carcinoma that do not have any of the following risk factors: tumor diameter >2 cm, elevated serum CA125, and a CT scan positive for lymphadenopathy. We believe that these new criteria will limit inter-institutional differences as they are all objective factors. Further, they are useful in predicting lymph node metastasis, including para-aortic lymph node metastasis, based on the number of risk factors present.

Vasohibin‐1 (VASH1) is a VEGF‐inducible endothelium‐derived angiogenesis inhibitor, and vasohibin‐2 (VASH2), its homolog, exhibits proangiogenic activity. VASH2 is expressed by various cancer cells and accelerates tumor angiogenesis and progression. VASH2 was recently shown to exhibit tubulin carboxypeptidase (TCP) activity related to microtubule functions. Paclitaxel (PTX), an effective chemotherapeutic agent that is widely used to treat ovarian cancer, inhibits microtubule depolymerization and may interact with VASH2. We herein established several VASH2 knockout ovarian cancer cell lines using the CRISPR/Cas9 genome editing system to examine the intracellular tubulin detyrosination status and PTX chemosensitivity. The knockout of VASH2 did not affect the proliferation or sphere‐forming activity of ovarian cancer cells in vitro. A Western blot analysis of VASH2 knockout cells revealed the weak expression of detyrosinated tubulin and upregulated expression of cyclin B1. The knockout of VASH2 significantly increased chemosensitivity to PTX, but not to cisplatin in ovarian cancer cell lines. The knockout of VASH2 reduced TCP activity and increased cyclin B1 expression, resulting in increased PTX chemosensitivity in ovarian cancer cells. The inhibition of angiogenesis and regulation of microtubule activity may be achieved in ovarian cancer treatment strategies targeting VASH2.