Hemorrhagic morbidity in nulliparous patients with placenta previa without placenta accrete spectrum disorders

Background

Placental adhesion spectrum (PAS) is a disease in which the trophoblast invades the myometrium, and is a well-known high-risk condition associated with placental previa.

Aim

The morbidity of nulliparous women with placenta previa without PAS disorders is unknown.

Patients and Methods

The data from nulliparous women who underwent cesarean delivery were collected retrospectively. The women were dichotomized into malpresentation (MP) and placenta previa groups. The placenta previa group was categorized into previa (PS) and low-lying (LL) groups. When the placenta covers the internal cervical os, it is called placenta previa, when the placenta is near the cervical os, it is called the low-lying placenta. Their maternal hemorrhagic morbidity and neonatal outcomes were analyzed and adjusted using multivariate analysis based on univariate analysis.

Results

A total of 1269 women were enrolled: 781 women in the MP group and 488 women in the PP-LL group. Regarding packed red blood cell transfusion, PP and LL had adjusted odds ratio (aOR) of 14.7 (95% confidence interval (CI): 6.6 - 32.5), and 11.3 (95% CI: 4.9 - 26) during admission, and 51.2 (95% CI: 22.1 - 122.7) and 10.3 (95% CI: 3.9 - 26.6) during operation, respectively. For intensive care unit admission, PS and LL had aOR of 15.9 (95% CI: 6.5 - 39.1) and 3.5 (95% CI: 1.1 - 10.9), respectively. No women had cesarean hysterectomy, major surgical complications, or maternal death.

Conclusion

Despite placenta previa without PAS disorders, maternal hemorrhagic morbidity was significantly increased. Thus, our results highlight the need for resources for those women with evidence of placenta previa including a low-lying placenta, even if those women do not meet PAS disorder criteria. In addition, placenta previa without PAS disorder was not associated with critical maternal complications.

miR-766-5p targets super-enhancers by downregulating CBP and BRD4

Super-enhancers (SE) are clusters of transcription enhancers that drive gene expression. SEs are typically characterized by high levels of acetylation of histone H3 lysine 27 (H3K27ac), which is catalyzed by the histone lysine acetyltransferase CREB binding protein (CBP). Cancer cells frequently acquire tumor-specific SEs at key oncogenes, such as MYC, which induce several hallmarks of cancer. BRD4 is recruited to SEs and consequently functions as an epigenetic reader to promote transcription of SE-marked genes in cancer cells. miRNAs can be potent candidates for nucleic acid therapeutics for cancer. We previously identified miR-766-5p as a miRNA that downregulated MYC expression and inhibited cancer cell growth in vitro. In this study, we show that miR-766-5p directly targets CBP and BRD4. Concurrent suppression of CBP and BRD4 cooperatively downregulated MYC expression in cancer cells but not in normal cells. Chromatin immunoprecipitation analysis revealed that miR-766-5p reduced levels of H3K27ac at MYC SEs via CBP suppression. Moreover, miR-766-5p suppressed expression of a BRD4-NUT fusion protein that drives NUT midline carcinoma (NMC). In vivo administration of miR-766-5p suppressed tumor growth in two xenograft models. Collectively, these data suggest that targeting SEs using miR-766-5p-based therapeutics may serve as an effective strategy for the treatment of MYC-driven cancers.

Concurrent targeting of MAP3K3 and BRD4 by miR-3140-3p overcomes acquired resistance to BET inhibitors in neuroblastoma cells

Neuroblastoma (NB) harboring MYCN amplification is a refractory disease with a poor prognosis. As BRD4, an epigenetic reader belonging to the bromodomain and extra terminal domain (BET) family, drives transcription of MYCN in NB cells, BET inhibitors (BETis) are considered useful for NB therapy. However, clinical trials of BETis suggested that early acquired resistance to BETis limits their therapeutic benefit. MicroRNAs are small non-coding RNAs that mediate post-transcriptional silencing of target genes. We previously identified miR-3140-3p as a potent candidate for nucleic acid therapeutics for cancer, which directly targets BRD4. We demonstrated that miR-3140-3p suppresses tumor cell growth in MYCN-amplified NB by downregulating MYCN and MYC through BRD4 suppression. We established BETi-acquired resistant NB cells to evaluate the mechanism of resistance to BETi in NB cells. We revealed that activated ERK1/2 stabilizes MYCN protein by preventing ubiquitin-mediated proteolysis via phosphorylation of MYCN at Ser62 in BETi-acquired resistant NB cells, thereby attenuating the effects of BETi in these cells. miR-3140-3p efficiently downregulated MYCN expression by directly targeting the MAP3K3-ERK1/2 pathway in addition to BRD4 suppression, inhibiting tumor cell growth in BETi-acquired resistant NB cells. This study suggests that miR-3140-3p has the potential to overcome resistance to BETi in NB.

SOX2 enhances cell survival and induces resistance to apoptosis under serum starvation conditions through the AKT/GSK-3β signaling pathway in esophageal squamous cell carcinoma

The human SOX2 gene was recently identified as a novel major oncogene, recurrently amplified and overexpressed in esophageal squamous cell carcinoma (ESCC). However, the role and molecular mechanism of SOX2 in the carcinogenesis of ESCC remain to be elucidated. The present study investigated the effect of SOX2 on ESCC cell survival and resistance to apoptosis under serum starvation conditions. An adenoviral vector-mediated expression system and RNA interference were used to study the effect of SOX2. The present results revealed that SOX2 promoted ESCC cell survival and enhanced resistance to apoptosis under serum starvation conditions, but not in culture conditions with serum. Mechanistically, SOX2 increased the expression levels of phosphorylated AKT and glycogen synthase kinase-3β (GSK-3β), a downstream factor of AKT, under serum starvation conditions, leading to the promotion of ESCC cell survival. Additionally, SOX2 activated AKT through the PTEN/PI3K/phosphoinositide-dependent protein kinase 1 and mammalian target of rapamycin complex 2 signaling pathways. Therefore, SOX2 may facilitate the survival of ESCC cells under poor nutrient conditions by activating the AKT/GSK-3β signaling pathway.

Clinical impact of hemizygous deletion detection and panel-size in comprehensive genomic profiling

e15671

Background: Comprehensive genomic profiling (CGP) identified single nucleotide variants (SNVs), copy number alteration (CNA), indels, and rearrangements in cancer-related genes. Only limited CGP detects hemizygous deletion. Also panel size differs among CGPs. Clinical impact of hemizygous deletion and panel-size are not well characterized. Methods: Formalin-fixed paraffin-embedded tissues from 10 cancer patients were analyzed by two CGPs: 1) test A (ACT Onc+) that interrogates SNVs, indels, rearrangement, and CNA including amplification, hemizygous and homozygous deletions in 440 genes, 2) test B that interrogates SNV, indels, rearrangement and CNA including amplification and homozygous deletion in 114 genes, but hemizygous deletion only in limited genes. Result was discussed in molecular tumor board and actionable genes and candidate drug were determined. Primary objective was the number of actionable genomic alterations. Secondary objectives are the number of candidate drugs, SNVs, CAN, and rearrangement. When there was difference of results in two tests, other validation test, such as PCR-based copy number evaluation, was performed. The difference of two tests was statistically evaluated using student t-test. Results: Median age of patients was 56 (range 48 – 70), and 50% were male. Tumor types were neuroendocrine tumor (60%), ovarian cancer (30%) and pancreatic cancer (10%). In 10 patients, actionable genes were found as follows: 39 in test A and 9 in test B (P = 0.0056). Total 64 genomic alterations were found in test A compared 12 in test B. SNV was not statistically different among two tests (10 in test A, 6 in test B; P = 0.269). However, the number of CNA was different: 54 in test A and 6 in test B (P = 0.007). Among CNA, hemizygous alteration explained majority of the difference (30 in test A and 1 in test B, P = 0.059), followed by amplification (24 in test A and 5 in test B, P = 0.201). The number of drug candidates was 38 in test A and 11 in test B (P = 0.014). Conclusions: Detection of hemizygous deletion and larger panel size resulted in more actionable genes and drug candidates, which might impact clinical practice. Future study of clinical utility of hemizygous deletion and panel size is warranted.

miR-1293, a Candidate for miRNA-Based Cancer Therapeutics, Simultaneously Targets BRD4 and the DNA Repair Pathway

BRD4, a member of the bromodomain and extra-terminal domain (BET) protein family, plays a role in the organization of super-enhancers and transcriptional activation of oncogenes in cancer and is recognized as a promising target for cancer therapy. microRNAs (miRNAs), endogenous small noncoding RNAs, cause mRNA degradation or inhibit protein translation of their target genes by binding to complementary sequences. miRNA mimics simultaneously targeting several tumor-promoting genes and BRD4 may be useful as therapeutic agents of tumor-suppressive miRNAs (TS-miRs) for cancer therapy. To investigate TS-miRs for the development of miRNA-based cancer therapeutics, we performed function-based screening in 10 cancer cell lines with a library containing 2,565 human miRNA mimics. Consequently, miR-1293, miR-876-3p, and miR-6571-5p were identified as TS-miRs targeting BRD4 in this screening. Notably, miR-1293 also suppressed DNA repair pathways by directly suppressing the DNA repair genes APEX1 (apurinic-apyrimidinic endonuclease 1), RPA1 (replication protein A1), and POLD4 (DNA polymerase delta 4, accessory subunit). Concurrent suppression of BRD4 and these DNA repair genes synergistically inhibited tumor cell growth in vitro. Furthermore, administration of miR-1293 suppressed in vivo tumor growth in a xenograft mouse model. These results suggest that miR-1293 is a candidate for the development of miRNA-based cancer therapeutics.

22 Vitrification of bovine embryo using antifreeze polyamino acid

Carboxylated poly-l-lysine (CPLL) is an ampholytic polymer compound and a polyamino acid with a known functional resemblance to antifreeze proteins. We previously reported that CPLL is an effective cryoprotectant for bovine cells, sperm, and slow-frozen embryos. In this study, we investigated CPLL as a cryoprotectant for vitrified bovine embryos. We developed bovine embryos in vitro and vitrified them at the blastocyst stage. Embryos were equilibrated (3min) and vitrified (1min). Vitrified embryos were cryopreserved in LN (Cryotop® device; Kitazato Corp., Tokyo, Japan) for at least 1 week, thawed with a 0.3M sucrose warming solution, and then cultured in a basal medium (Gibco® medium 199, Grand Island, NY, USA; supplemented with 100µM 2-mercaptoethanol, 10% fetal bovine serum, and antibiotics) at 38.5°C in a humidified atmosphere (5% CO2, 5% O2, 90% N2). We evaluated the embryos morphologically for survival and hatched rate at 0, 24, 48, and 72h post-thawing. In control, the equilibration solution (ES) consisted of 7.5% (vol/vol) dimethyl sulfoxide (DMSO) and 7.5% (vol/vol) ethylene glycol, and the vitrification solution (VS) consisted of 16.5% (vol/vol) DMSO and 16.5% (vol/vol) ethylene glycol and 0.5M sucrose. In this study, CPLL was added to ES and VS at various concentrations instead of DMSO. The CPLL was added at 16.5, 11.0, 5.5, and 2.2% (wt/vol) to VS; respectively, these solutions were named P16.5, P11.0, P5.5, and P2.2. The ES was used 45% CPLL of VS each. Embryos underwent the above procedure concurrently, with testing replicated at least 3 times. We evaluated 88, 34, 38, 44, and 28 embryos with each solution (control, P16.5, P11.0, P5.5, and P2.2, respectively). Results were analysed statistically with a chi-square test and residual analysis, regarding P<0.05 as significant. Survival rates were significantly greater in P11.0 at 24h post-thawing (55.7% v. 89.5%; P<0.05) and in P11.0 and P5.5 at 48h post-thawing (47.7% v. 78.9% and 47.7% v. 79.5%, respectively; P<0.05) relative to controls but showed no significant differences at 0h post-thawing. Hatched rates were significantly greater in P11.0 and P5.5 through 72h post-thawing relative to controls (44.7% v. 22.7% and 52.3% v. 22.7%, respectively; P<0.05). The CPLL improved post-thawing embryo survival and hatched rates when applied during vitrification, thus demonstrating cryoprotective effectiveness. We conclude that CPLL acts as a low-toxicity cryoprotectant for vitrified bovine embryos, and our results are consistent with previous reports of protective CPLL effects for cells and cell membranes.

176 Effect of epigallocatechin-3-gallate on bovine oocyte in vitro maturation, fertilization, and development

Epigallocatechin-3-gallate (EGCG) is a major ingredient of catechin polyphenols, and a strong antioxidant compound. Huang et al. (2018 Asian-australas. J. Anim. Sci.) reported that adding 50μM EGCG can improve the bovine oocyte maturation rate. In this research, we investigated the effect of EGCG supplementation on different periods in bovine IVF. Cumulus-oocyte complex (COC) collected from ovaries of slaughtered cows were cultured in maturation medium (20 to 30 oocytes per 100-µL droplet), which consisted of TCM-199 with Earle’s salts and 25mM HEPES supplemented with 10% (vol/vol) fetal bovine serum (FBS), 1µg mL−1 oestradiol, 0.02mg mL−1 FSH, and antibiotics at 38.5°C in a humidified atmosphere of 5% CO2 in air for 24h (in vitro maturation, IVM). After IVM, COC were fertilized in the fertilization medium (modified Brackett-Oliphant media supplemented with 10 µgmL−1 heparin, 10mM caffeine, and 3mg mL−1 BSA) for 6h using semen of one bull at final sperm concentration of 1×107 mL−1 (IVF). After IVF, COC were denuded and cultured in culture medium [CR1aa supplemented with 10% (vol/vol) FBS and antibiotics] at 38.5°C in a humidified atmosphere of 5% O2, 5% CO2, and 90%N2 for 8 days (in vitro culture, IVC). The EGCG was supplemented at 10, 25, 50, and 100M in IVM medium; 25 and 50 µM in IVF medium; and 50 and 100 µM in IVC medium. After 24h in IVM medium, COC were denuded by pipetting, fixed in 3:1 ethanol:acetic acid for 24h and then checked for nuclear and polar body by using aceto-orcein stain. After 18h in IVF, the pronucleus in zygote was fixed in 3:1 ethanol:acetic acid for 24h and checked by aceto-orcein staining. Embryo development was evaluated by counting the total number of embryos that had reached compacted morula by 6 to 8 days after IVF. Significant differences were analysed by chi-squared test and residual analysis. A P-value<0.05 was considered statistically significant. When EGCG was added to IVM, there was no significant difference of oocyte maturation rate between all concentrations (0v. 10v. 25v. 50v. 100 μM: 73.9% v. 56.7% v. 76.7% v. 72.7% v. 63.5%). When EGCG was added to IVF, there was no significant difference of fertilized rate (0v. 25v. 50 μM: 59.4% v. 73.7% v. 64.9%). When EGCG was added to IVC, there was no significant difference in development rate (0v. 50v. 100 μM: 26.2% v. 15.7% v. 22.0%). In this research, EGCG addition did not affect bovine in vitro fertilization.

Blue laser imaging-bright improves the real-time detection rate of early gastric cancer: a randomized controlled study

BACKGROUND AND AIMS

Blue laser imaging-bright (BLI-bright) has shown promise as a more useful tool for detection of early gastric cancer (EGC) than white-light imaging (WLI). However, the diagnostic performance of BLI-bright in the detection of EGC has not been investigated. We aimed to compare real-time detection rates of WLI with that of BLI-bright for EGC.

METHODS

This was a prospective, randomized, controlled study in 2 Japanese academic centers. We investigated 629 patients undergoing follow-up endoscopy for atrophic gastritis with intestinal metaplasia or surveillance after endoscopic resection of EGC. Patients were randomly assigned to receive primary WLI followed by BLI-bright or primary BLI-bright followed by WLI. The real-time detection rates of EGC were compared between primary WLI and primary BLI-bright.

RESULTS

There were 298 patients in each group. The real-time detection rate of EGC with primary BLI-bright was significantly greater than that with primary WLI (93.1% vs 50.0%; P = .001). Primary BLI-bright had a significantly greater ability to detect EGCs in patients with a history of endoscopic resection for EGC, no Helicobacter pylori infection in the stomach after eradication therapy, lesions with an open-type atrophic border, lesions in the lower third of the stomach, depressed-type lesions, small lesions measuring <10 mm and 10 to 20 mm in diameter, reddish lesions, well-differentiated adenocarcinomas, and lesions with a depth of invasion of T1a.

CONCLUSIONS

BLI-bright has a higher real-time detection rate for EGC than WLI. BLI-bright should be performed during surveillance endoscopy in patients at high risk for EGC. (Clinical trial registration number: UMIN000011324.).

Abstract LB-385: miR-3140 suppresses tumor cell growth by targeting BRD4 via its coding sequence and downregulates the BRD4-NUT fusion oncoprotein

Bromodomain Containing 4 (BRD4) mediates transcriptional elongation of the oncogene MYC by binding to acetylated histones. BRD4 has been shown to play a critical role in tumorigenesis in several cancers, and the BRD4-NUT fusion gene is a driver of NUT midline carcinoma (NMC), a rare but highly lethal cancer. microRNAs (miRNAs) are endogenous small non-coding RNAs that suppress target gene expression by binding to complementary mRNA sequences. Here, we show that miR-3140, which was identified as a novel tumor suppressive miRNA by function-based screening of a library containing 1090 miRNA mimics, directly suppressed BRD4 by binding to its coding sequence (CDS). miR-3140 concurrently downregulated BRD3 by bind to its CDS as well as CDK2 and EGFR by binding to their 3' untranslated regions. miR-3140 inhibited tumor cell growth in vitro in various cancer cell lines, including EGFR tyrosine kinase inhibitor-resistant cells. Interestingly, we found that miR-3140 downregulated the BRD4-NUT fusion protein and suppressed in vitro tumor cell growth in a NMC cell line, Ty-82 cells. Furthermore, administration of miR-3140 suppressed in vivo tumor growth in a xenograft mouse model. Our results suggest that miR-3140 is a candidate for the development of miRNA-based cancer therapeutics.

Citation Format: Tomoki Muramatsu, Erina Tonouchi, Yasuyuki Gen, Hidekazu Hiramoto, Kousuke Tanimoto, Jun Inoue, Johji Inazawa. miR-3140 suppresses tumor cell growth by targeting BRD4 via its coding sequence and downregulates the BRD4-NUT fusion oncoprotein [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-385.

Risk factors for Korean women to develop an isthmocele after a cesarean section

BACKGROUND

The increase in number of cesarean section (CS) operations has resulted in an increase in cases of isthmocele development. The objective of this study is to determine the risk factors for isthmocele development after CS.

METHODS

Isthmocele measurements were taken for 404 women with a history of at least one low transverse CS. The following potential risk factors were investigated: patient's age at CS, cause of CS, weeks of gestation at CS, premature rupture of membrane (PROM), phase of labor, type suture (single/double layer), operation time, uterine flexion (anteversion/retroversion), and blood transfusion during operation. A transvaginal ultrasound was carried out to examine the isthmocele in the uterus after CS, including the shape of the isthmocele, residual myometrial thickness, depth and width of isthmocele, cervical thickness, location of the isthmocele, and clinical characteristics.

RESULTS

In our study population, the isthmocele had a prevalence of 73.8%. Most isthmocele had a triangular (65.4%) or semicircular shape (10.4%). The presence of an isthmocele was significantly associated with repeat CS, premature rupture of membrane (PROM), short operation time, and extent of cervix dilatation at CS. The risk of isthmocele was low in women who had placenta previa totalis (PPT), twin, a long operation time, or a transfusion during the operation.

CONCLUSIONS

In our study, isthmocele development was significantly associated with repeat CS, PROM, a short operation time, and the extent of cervix dilatation at CS. Therefore, PROM prevention and a more careful uterine closure are needed to reduce the risk of developing an isthmocele after CS.

Oncogenic miR-96-5p inhibits apoptosis by targeting the caspase-9 gene in hepatocellular carcinoma

The aberrant expression or alteration of microRNAs (miRNAs/miRs) contributes to the development and progression of cancer. In the present study, the functions of miR-96-5p in hepatocellular carcinoma (HCC) were investigated. It was identified that miR-96-5p expression was significantly upregulated in primary HCC tumors compared with their non-tumorous counterparts. A copy number gain was frequently observed at chromosomal region 7q32.2 in which the MIR96 locus is located, suggesting that gene amplification may be one of the mechanisms by which miR-96-5p expression is increased in HCC. Transfection of miR-96-5p mimic into HCC cells decreased the expression of CASP9, which encodes caspase-9, the essential initiator caspase in the mitochondrial apoptotic pathway, at the mRNA and protein levels. A putative binding site for miR-96-5p was identified in the CASP9 3'-untranslated region, and the results of a luciferase assay indicated that CASP9 is a potential direct target of miR-96-5p. The miR-96-5p mimic increased resistance to doxorubicin- and ultraviolet-induced apoptosis through the decrease in caspase-9 expression in HCC cells. Transfection of miR-96-5p inhibitor enhanced the cytotoxic effect of doxorubicin by increasing caspase-9 expression in the HCC cells, suggesting a synergistic effect between the miR-96-5p inhibitor and doxorubicin. In conclusion, the results of the present study suggest that miR-96-5p, which is frequently upregulated in HCC, inhibits apoptosis by targeting CASP9. Therefore, miR-96-5p may be a potential therapeutic target for HCC.

43 Cryopreservation of Bovine Sperm Using Antifreeze Polyamino-Acid

Carboxylated poly-l-lysine (CPLL), an ampholytic polymer compound, is reported to have a cryoprotective property similar to that of antifreeze proteins. We previously reported the effectiveness of CPLL as cryoprotective material for bovine sperm (43rd Annual Conference of International Embryo Technology Society, Austin, TX, USA; http://www.iets.org/2017/IETS_2017_Program_Book_FINAL.pdf). In this research, we investigated additional aspects of CPLL for bovine sperm. The conventional cryopreservation medium used for Control group consisted of 6.5% (v/v) glycerin, and the cryopreservation medium used for the CPLL group consisted of 3.25% (v/v) glycerin and 0.5% CPLL (w/v). In experiment 1, sperm motility was measured 1, 3, and 6 h after thawing. The post-thaw motility was assessed by using Sperm Motility Analysis System (DITECT Corp., Tokyo, Japan). The CPLL treatment yielded better motility rate at 6 h (Control v. CPLL; 23.7% v. 38.5%; P < 0.01), average path velocity (μm s−1) at 1 and 3 h (Control v. CPLL; 49.8 v. 57.7, 35.8 v. 42.8; P < 0.01), straight-line velocity (μm s−1) at 1 h (Control v. CPLL; 35.2 v. 45.7; P < 0.01), and curvilinear velocity (μm/s) at 1 and 3 h (Control v. CPLL; 93.7 v. 106.2, 59.9 v. 68.4; P < 0.01) than the Control. In experiment 2, sperm membrane integrity was assessed by using the LIVE/DEAD Sperm Viability Kit (Thermo Fisher Scientific K.K., Kanagawa, Japan). The CPLL group yielded greater sperm membrane integrity rate than control (Control v. CPLL; 49.6% v. 60.6%; P < 0.01). In experiment 3, AI was carried out on 111 cows (Control v. CPLL; 49 v. 62) and the conception rate of the CPLL group was significantly higher than that of the control group (53.1% v. 79.0%; P < 0.01). Previously, we reported the effectiveness of CPLL for bovine sperm. In this study, we clarified how CPLL works to improve the conception rate of AI: CPLL maintains post-thaw motility and protects the sperm membrane. These results suggest that CPLL has potential as a new cryoprotective material for bovine sperm.

Abstract 2539: MiR-96-5p functions as an oncogenic miRNA by inhibiting apoptosis in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most aggressive cancers with high mortality worldwide. MicroRNAs (miRNAs) are small non-coding RNAs that have been used as cancer-related biomarkers and expected to be therapeutic agents. We performed genome-wide miRNA expression profiling of paired HCC tumors and non-tumorous liver tissues from patients with primary HCCs using the miRNA microarray (Agilent). We found that miR-96-5p was most significantly up-regulated in HCC tumors compared to non-tumor tissues. Although miR-96-5p is suggested to be an oncogenic miRNA, the function of miR-96-5p remains largely unknown. We identified the caspase-9 gene (CASP9) as a novel target of miR-96-5p, in addition to the forkhead box O1 gene (FOXO1) which is the known target of it. Caspase-9 protein is thought to play a central role in apoptosis and to be a tumor suppressor. Overexpression of miR-96-5p decreased caspase-9 protein expression and resulted in resistance to apoptosis induced by doxorubicin and UV in HCC cells. Our results suggested that miR-96-5p functions as an oncogenic miRNA by inhibiting apoptosis through decreasing caspase-9 expression in HCC.

Citation Format: Naoto Iwai, Kohichiroh Yasui, Akira Tomie, Kei Teasaki, Tomoko Kitaichi, Osamu Dohi, Yasuyuki Gen, Yoshito Ito. MiR-96-5p functions as an oncogenic miRNA by inhibiting apoptosis in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2539. doi:10.1158/1538-7445.AM2017-2539

Abstract 3433: Epigenetic silencing of miR-214-3p is associated with resistance to p53-induced apoptosis through up-regulation of gankyrin expression in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression and can act as tumor suppressors or oncogenes. To identify miRNA involved in the development of HCC, a genome-wide miRNA gene expression analysis was performed using the human miRNA microarray (Agilent) in paired HCC tumors and non-tumorous liver tissues from patients with primary HCC. The array-based miRNA expression profiles were validated by quantitative PCR. We also screened for genes with promoter DNA hypermethylation using a genome-wide DNA methylation microarray analysis (the Illumina HumanMethylation27 BeadChip) in the same samples. We found that miR-214-3p were significantly down-regulated by aberrant promoter hypermethylation in HCC tumors compared to the non-tumorous liver tissues. We identified PSMD10, which encodes gankyrin, as a direct target of miR-214-3p using luciferase assay and immunoblotting. Gankyrin, an oncoprotein commonly overexpressed in HCC, binds to MDM2, a major E3 ubiquitin ligase for p53, and increases ubiquitylation and degradation of p53. Our experiments showed that reduced miR-214-3p expression was associated with resistance to p53-induced apoptosis through up-regulation of gankyrin expression in HCC cells. In conclusion, our results suggest that epigenetic silencing of tumor suppressor miR-214-3p is involved in hepatocarcinogenesis through up-regulation of gankyrin expression.

Citation Format: Kohichiroh Yasui, Naoto Iwai, Kei Terasaki, Yasuyuki Gen, Yoshito Itoh. Epigenetic silencing of miR-214-3p is associated with resistance to p53-induced apoptosis through up-regulation of gankyrin expression in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3433. doi:10.1158/1538-7445.AM2017-3433

ASPP2 suppresses invasion and TGF-β1-induced epithelial-mesenchymal transition by inhibiting Smad7 degradation mediated by E3 ubiquitin ligase ITCH in gastric cancer

ASPP2 regulates cell polarity and cell-cell adhesion by binding to, and co-localizing with PAR3 at tight junctions. Here we show a novel role of ASPP2 in suppressing gastric cancer (GC) invasiveness. Immunoprecipitation and immunofluorescence analyses showed that ASPP2 promoted the recruitment of PAR3 to cell-cell junctions in GC cells. Diminished expression of ASPP2 and loss of junctional PAR3 localization were significantly associated with diffuse-type histology, deeper invasion depth, positive peritoneal dissemination and worse prognosis in primary GC. ASPP2 suppressed migration and invasion of GC cells in vitro and peritoneal dissemination of GC cells in vivo in a mouse model. ASPP2 suppressed epithelial-mesenchymal transition (EMT) induced by TGF-β1-Smad2/3 signaling in GC cells through suppression of the degradation of Smad7, a negative regulator of TGF-β1-Smad2/3 signaling, by interacting with the E3 ubiquitin ligase ITCH. In conclusion, ASPP2 suppresses invasion, peritoneal dissemination and TGF-β1-induced EMT by inhibiting Smad7 degradation mediated by ITCH.

52 CRYOPRESERVATION OF BOVINE SOMATIC CELL USING ANTIFREEZE POLYAMINO-ACID (CARBOXYLATED POLY-L-LYSINE)

Cryopreservation is used for long-term preservation of biological materials containing cell and tissue, somatic cells are important to commercial application in gene bank and medical engineer. For cell cryopreservation, dimethyl sulfoxide (DMSO) have been used widely as cryoprotective material for long time. Carboxylated poly-l-lysine (CPLL) is an ampholytic polymer compound obtained by converting 65% amino groups to carboxyl groups after synthesising ε-poly-l-lysine aqueous solution and succinic anhydride. It is reported that the addition of CPLL into cryopreservation medium improves the post-thaw survival rate of murine L929 cells, human induced pluripotent stem cells and murine embryo. In this research, the effectiveness of CPLL as bovine somatic cell cryoprotective material was examined. In experiment 1, using bovine fibroblast cells from skin, the cryopreservation media were prepared as follows: 10% (vol/vol) DMSO, 5% (vol/vol) DMSO + 5% (wt/vol) CPLL, 5% (wt/vol) CPLL, 7.5% (wt/vol) CPLL, 10% (wt/vol) CPLL and 20% (wt/vol) CPLL were dissolved in DMEM and pH was adjusted to 7.4. Cells were resuspended in 1 mL of cryopreservation medium at a cell density of 5 × 105 and stored in a −80°C freezer. After storage for at least 1 wk, cells were thawed. The 5% CPLL showed significantly higher post-thaw survival rate than 10% DMSO (96.5% v. 86.7%; P < 0.05), and 7.5% CPLL and 20% CPLL showed significantly higher proliferation rates than 10% DMSO at 72 h after thawing (10% DMSO v. 7.5% CPLL v. 20% CPLL ; 99.4% v. 173.6% v. 207.4%; P < 0.05). Although it is necessary to remove the cryoprotective material after thawing, the proliferation rate at 72 h after thawing of 5% CPLL and 10% CPLL without removal of cryoprotective material were significantly higher than that when removing cryoprotective material (111.2% v. 269.6%, 113.0% v. 210.0%). In addition, there was no difference between the removal treatment of CPLL and the NOT removal treatment of CPLL at the thawing. In experiment 2, using bovine cumulus cells, the cryopreservation media were prepared as follows: 10% (vol/vol) DMSO, 5% (vol/vol) DMSO + 5% (wt/vol) CPLL, 5% (wt/vol) CPLL, 10% (wt/vol) CPLL, 20% (wt/vol) CPLL, 25% (wt/vol) CPLL, and 30% (wt/vol) CPLL were dissolved in DMEM and other conditions were the same as experiment 1. There was no significant difference for post-thaw survival rate (93.7, 91.8, 89.2, 89.2, 95.3, 91.6, and 90.2%). At 72 h after thawing, 10% DMSO, 5% DMSO + 5% CPLL and 25% CPLL showed higher proliferation rate (10% DMSO v. 5% DMSO + 5% CPLL v. 25% CPLL; 258.4% v. 281.4% v. 257.4%). The significant differences in survival rate were determined by chi-squared test, and in proliferation were determined by ANOVA. In bovine somatic cells, it was possible to cryopreserve cells using CPLL without DMSO. The cryoprotective effect of CPLL is equal or superior to that of DMSO, the conventional cryoprotective material. Further, when using CPLL, it was possible to culture without removing the cryopreservation medium after thawing. These results suggest that CPLL has promise as a new cryoprotective material for bovine somatic cells.

47 CRYOPRESERVATION OF BOVINE GERM CELL USING ANTIFREEZE POLYAMINO-ACID (CARBOXYLATED POLY-L-LYSINE)

Carboxylated poly-l-lysine (CPLL) is an ampholytic polymer compound, and it is obtained by converting 65% amino groups to carboxyl groups after synthesising ε-poly-l-lysine aqueous solution and succinic anhydride. CPLL has cryoprotective property similar to antifreeze protein, and addition of CPLL into cryopreservation medium improves the post-thaw survival rate of cells and embryos. In this research, we examined the effectiveness of CPLL as a bovine germ cell cryoprotective material. In experiment 1 (in sperm), the conventional cryopreservation medium used for control group was consisted of 6.5% (vol/vol) glycerin, and the cryopreservation medium used for CPLL group was consisted of 3.25% (vol/vol) glycerin and 0.5% CPLL (wt/vol). The post-thaw survival and motility were assessed by using Sperm Motility Analysis System (DITECT Corp., Tokyo, Japan). There was no significant difference for post-thaw survival rate and motility (control v. CPLL; 98.8% v. 96.6% and 69.7% v. 62.2%, respectively). Artificial insemination was carried out in 65 cows (control v. CPLL; 34 v. 31), and the conception rate of the CPLL group was higher than that of the control group (80.6% v. 67.6%; P = 0.23). In experiment 2 (embryos), the conventional cryopreservation medium used for control group was consisted of 5% (vol/vol) ethylene glycol and 6% (vol/vol) propylene glycol in PBS. In the CPLL group, 7% (wt/vol) CPLL was added to the conventional medium. In vitro fertilization embryos were cryopreserved at Day 7 and Day 8. There was no significant difference in survival rate at 0, 24, and 48 h and hatched rate until 72 h after thawing (control v. CPLL: 93.6% v. 93.2%, 69.0% v. 64.7%, 56.1% v. 56.3%, 12.9% v. 10.2%, respectively). Embryos obtained by superovulation treatment and in vivo fertilization at Day 7 were cryopreserved using above 2 media, and transferred non-surgically into synchronized recipient cows (1 embryo per animal). Embryo transfer (ET) was carried out in 81 cows (control v. CPLL: 31 v. 50), and recipients were diagnosed for pregnancy ultrasonically 50 days after embryo transfer. Conception rate of CPLL group was higher than control group (50.0% v. 29.0%; P = 0.063). In both experiments, the significant differences between control group and CPLL group were determined by chi-squared test. The effectiveness of CPLL in cells and embryos has been reported; however, there is no report using CPLL in bovine germ cells. In this research, CPLL improved the conception rate of AI and ET, probably due to its low toxicity and protection of the cell membrane. These results suggest that CPLL is available as a new cryoprotective material for bovine sperm and embryo in slow freezing methods.

Abstract 963: Epigenetic silencing of miR-199a-3p is associated with increased cell survival, enhanced cell motility, and sensitivity to tivantinib through regulation of c-Met expression in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression and can act as tumor suppressors or oncogenes. To identify miRNA involved in the development of HCC, we performed a genome-wide miRNA gene expression analysis using the human miRNA microarray (Agilent) in paired tumor and non-tumor tissues from patients with primary HCC. The array-based miRNA expression profiles were validated by quantitative PCR. We also screened for genes with promoter DNA hypermethylation using a genome-wide DNA methylation microarray analysis (the Illumina HumanMethylation27 BeadChip) in primary HCCs. We found that miR-214-3p, miR-199a-5p, and miR-199a-3p were significantly down-regulated by aberrant promoter hypermethylation in HCC tumors. The c-Met gene was identified as the direct target of miR-199a-3p. Our study showed that reduced expression of miR-199a-3p was associated with increased cell survival through the c-Met/Akt pathway and enhanced cell motility through phosphorylation of FAK. The transfection of miR-199a-3p mimic reduced the expression of c-Met and enhanced the sensitivity to the c-Met inhibitor tivantinib in HCC cells. In conclusion, our results suggest that epigenetic silencing of tumor suppressor miR-199a-3p may be involved in hepatocarcinogenesis through regulation of c-Met expressionand and be associated with the sensitivity to tivantinib.

Citation Format: Kohichiroh Yasui, Akira Tomie, Naoto Iwai, Tomoko Kitaichi, Osamu Dohi, Yasuyuki Gen, Yoshito Itoh. Epigenetic silencing of miR-199a-3p is associated with increased cell survival, enhanced cell motility, and sensitivity to tivantinib through regulation of c-Met expression in hepatocellular carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 963.

Abstract 1099: Up-regulated miR-96-5p inhibits apoptosis by targeting FOXO1 in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers and the third leading cause of cancer death worldwide, especially in Asia and sub-Saharan Africa. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression and can act as tumor suppressors or oncogenes. To identify miRNA involved in HCC, we performed a genome-wide miRNA gene expression analysis using the human miRNA microarray (Agilent) in paired tumor and non-tumor tissues from patients with primary HCC. The array-based miRNA expression profiles were validated by quantitative PCR. We identified miR-96-5p as the most significantly upregulated miRNA in HCC tumors. Although miR-96-5p has been recognized as an oncogenic miRNA, its role in the pathogenesis of HCC remains unknown. Our study showed that the inhibition of miR-96-5p reduced proliferation of HCC cells and induced apoptosis. Furthermore, we found that the forkhead box O1 (FOXO1) gene was a target of miR-96-5p. FOXO1, a transcription factor, plays an essential role in cell fate decisions. FOXO1 can induce apoptosis through mitochondria-dependent and mitochondria-independent pathways. Collectively, our results suggested that miR-96-5p may function as an oncogenic miRNA through inhibiting apoptosis by targeting FOXO1 in HCC.

Citation Format: Naoto Iwai, Kohichiroh Yasui, Akira Tomie, Tomoko Kitaichi, Osamu Dohi, Yasuyuki Gen, Yoshito Itoh. Up-regulated miR-96-5p inhibits apoptosis by targeting FOXO1 in hepatocellular carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1099.

A case of gastric hamartomatous inverted polyp resected endoscopically

We report the case of a 55-year-old woman with a tumor in the greater curvature of the upper gastric body. The tumor was incidentally found on an upper gastrointestinal X-ray series performed during a routine medical examination. Whereas endoscopy revealed a gastric submucosal tumor (SMT), endoscopic ultrasonography demonstrated a heterogeneous tumor with small, cystic, hypoechoic spots originating from the second layer. The patient was clinically asymptomatic, with no contributory family history or abnormal laboratory data. The results of a physical examination, abdominal computed tomography, and plain chest radiography were all unremarkable. Although the endoscopic tumor type was determined to be SMT, the tumor was successfully resected by endoscopic submucosal dissection (ESD) and subsequently diagnosed as a gastric hamartomatous inverted polyp (GHIP). The findings of the present case highlight the importance of considering GHIP as a diagnosis and indicate the utility of en bloc resection of GHIP with ESD.

Abstract 2103: SOX2 suppresses PTEN expression via miR-19a in esophageal squamous cell carcinoma

We previously showed that SOX2, a master regulator during embryogenesis, is an amplification target of 3q26.33 in esophageal squamous cell carcinoma (ESCC), and that SOX2 promotes ESCC proliferation in vitro and in vivo via activation of the AKT/mammalian target of rapamycin complex 1 (mTORC1) signaling pathway. However, the mechanisms by which SOX2 promotes AKT/mTORC1 signaling remain to be elucidated. We determined that SOX2 decreased PTEN, a negative regulator of AKT signaling, via microRNA (miRNA) in ESCC cells. SOX2 knockdown increased PTEN and decreased phosphorylated AKT (p-AKT), and PTEN knockdown restored p-AKT decreased by SOX2 knockdown in SOX2 amplified ESCC cells (KYSE70, KYSE140 and TE10 cells), indicating that SOX2 elevates p-AKT via PTEN suppression in these cells. DICER knockdown increased PTEN expression without SOX2 expression change in these cells, suggesting that PTEN expression is regulated by miRNA. Therefore we hypothesized that SOX2 may suppress PTEN expression through miRNA regulation. To examine whether SOX2 modulate the expression of miRNAs, we investigated the expression of cancer-related 84 miRNAs using miRNA PCR arrays, and found that SOX2 elevated miR-17∼92 cluster (miR-17, miR-18a, miR-19a, miR-19b-1, miR-20a, and miR-92) in KYSE70 cells. Quantitative RT-PCR confirmed that the expression of mir-17∼92 cluster is elevated by SOX2 in KYSE70, KYSE140, and TE10 cells. Of these miRNA, transfection of miR-19a mimic suppressed PTEN and conversely miR-19a inhibition elevated PTEN in these cells. Collectively, SOX2 may suppress PTEN expression via miR-19a in ESCC cells.

Citation Format: Yasuyuki Gen, Kohichiroh Yasui, Tomoko Kitaichi, Osamu Dohi, Yoshito Ito. SOX2 suppresses PTEN expression via miR-19a in esophageal squamous cell carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2103. doi:10.1158/1538-7445.AM2015-2103

Abstract 4950: Defective expression of partition-defective 3 (PAR-3) is associated with adverse prognostic factors in esophageal squamous cell carcinoma

Esophageal cancer is the sixth leading cause of cancer mortality and squamous cell carcinoma is a prevalent histological subtype worldwide. The partition-defective 3 (PAR-3) protein belongs to a partition defective complex that controls polarity, which is mainly composed of PAR-3, PAR-6, and atypical protein kinase C (aPKC). PAR-3 contains one self-oligomerization domain in the N-terminus, three PDZ protein interaction domains and one aPKC-binding domain. Owing to these domains, PAR-3 is able to form a conserved protein complex with PAR-6 and aPKC. In mammalian epithelial cells, PAR complex assembles at tight junctions, and plays a role in controlling apical-basal polarity, asymmetric cell division, and directional cell migration. It is well known that disrupted cell polarity is a feature of epithelial cancers. Therefore, it is believed that PAR proteins may be involved in multiple aspects of oncogenesis and tumor-promoting function. We previously detected a homozygous deletion of PAR-3 gene in esophageal squamous cell carcinoma (ESCC) cell lines by a high-density oligonucleotide microarray approach. (Oncogene 28:2910-2918, 2009). A copy number loss of PAR-3 gene was observed in 15% of primary ESCC tumors. The expression of PAR-3 mRNA was significantly reduced in 70% of ESCC tumors when compared with their nontumorous tissue counterparts. Exogenous expression of PAR-3 gene in ESCC cells lacking this gene (KYSE30 cells) enhanced the recruitment of Zonula occludens 1 (ZO-1), a marker of tight junctions, to sites of cell-cell contact. Conversely, knockdown of PAR-3 gene in ESCC cells expressing this gene disrupted ZO-1 localization at cell-cell borders. Although our previous findings suggested that deletion and reduced expression of PAR-3 gene may be a novel mechanism that drives the progression of ESCC, the clinical relevance of PAR-3 in ESCC tumor progression was not known. In the present study, we aimed to investigate the expression pattern of PAR-3 protein in primary ESCC tumors and to clarify any potential relationship between the PAR-3 expression and clinicopathological parameters. Immunohistochemical analyses showed that PAR-3 protein was expressed at the basal layer of the normal squamous epithelium of the esophagus, esophageal glands proper and the duct of esophageal glands. Both normal esophageal cells and ESCC tumor cells showed granular cytoplasmic staining and particularly strong membranous staining of PAR-3 protein. PAR-3 protein expression was lost in 20 (37%) of 74 primary ESCC tumors. Loss of PAR-3 protein expression was significantly associated with invasion depth (P = 0.0065) and lymph node metastasis (P = 0.03). Our results suggest that loss of PAR-3 protein expression may lead to tumor progression and subsequent lymph node metastasis in ESCC.

Citation Format: Tomoko Kitaichi, Koichiroh Yasui, Akira Tomie, Yasuyuki Gen, Osamu Dohi, Yuji Naito, Yoshito Itoh. Defective expression of partition-defective 3 (PAR-3) is associated with adverse prognostic factors in esophageal squamous cell carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4950. doi:10.1158/1538-7445.AM2015-4950

EVI1, a target gene for amplification at 3q26, antagonizes transforming growth factor-β-mediated growth inhibition in hepatocellular carcinoma

EVI1 (ecotropic viral integration site 1) is one of the most aggressive oncogenes associated with myeloid leukemia. We investigated DNA copy number aberrations in human hepatocellular carcinoma (HCC) cell lines using a high-density oligonucleotide microarray. We found that a novel amplification at the chromosomal region 3q26 occurs in the HCC cell line JHH-1, and that MECOM (MDS1 and EVI1 complex locus), which lies within the 3q26 region, was amplified. Quantitative PCR analysis of the three transcripts transcribed from MECOM indicated that only EVI1, but not the fusion transcript MDS1-EVI1 or MDS1, was overexpressed in JHH-1 cells and was significantly upregulated in 22 (61%) of 36 primary HCC tumors when compared with their non-tumorous counterparts. A copy number gain of EVI1 was observed in 24 (36%) of 66 primary HCC tumors. High EVI1 expression was significantly associated with larger tumor size and higher level of des-γ-carboxy prothrombin, a tumor marker for HCC. Knockdown of EVI1 resulted in increased induction of the cyclin-dependent kinase inhibitor p15(INK) (4B) by transforming growth factor (TGF)-β and decreased expression of c-Myc, cyclin D1, and phosphorylated Rb in TGF-β-treated cells. Consequently, knockdown of EVI1 led to reduced DNA synthesis and cell viability. Collectively, our results suggest that EVI1 is a probable target gene that acts as a driving force for the amplification at 3q26 in HCC and that the oncoprotein EVI1 antagonizes TGF-β-mediated growth inhibition of HCC cells.

Abstract 5186: Reduced expression of BRM in hepatocellular carcinoma

Background: Hepatocellular carcinoma (HCC) is the fifth most common malignancy in men and the eighth most common in women worldwide. The eukaryotic genome is organized into highly ordered chromatin structures in the nucleus. Chromatin creates a barrier to nuclear processes, such as transcription, by obstructing the access of the transcriptional machinery and gene-specific regulators to recognition sequences within target promoters. The SWI/SNF protein complex, an ATPase-dependent chromatin remodeling enzyme, mobilizes nucleosomes and functions as a master regulator of gene expression and chromatin dynamics. SWI/SNF is a large multiprotein complex that contains either BRG1 or brahma (BRM) as the catalytic ATPase. Each SWI/SNF complex thus incorporates one of two possible ATPases, BRG1 or BRM.

Aims: To examine alterations of BRG1 and BRM in HCC.

Methods: We investigated DNA copy number aberrations in human HCC cell lines using a high-density oligonucleotide microarray. We determined DNA copy numbers and expression levels of BRG1 and BRM genes in primary HCC tumors, and conducted further searches for mutations in BRG1 and BRM genes.

Results: Homozygous deletion of the BRG1 gene was found in HCC cell line SNU398. Copy number losses of BRG1 and BRM genes were observed in 14 (26%) and 7 (13%) of 54 primary HCC tumors respectively. We found four somatic missense mutations in the BRG1 gene in two of 36 primary HCC tumors, but no mutations in BRM gene. Expression of BRM mRNA, but not BRG1 mRNA, was significantly reduced in primary HCC tumors, compared to non-tumor tissue counterparts. Immunohistochemical analyses of non-tumour liver tissues showed that BRM protein was expressed in hepatocytes and bile-duct epithelial cells, whereas BRG1 protein was expressed in bile-duct epithelial cells, but not in hepatocytes. BRM protein expression was lost in nine (22.5%) of 40 HCC tumours. Loss of BRM protein expression was significantly associated with poor overall survival.

Conclusion: Reduced expression of BRM may contribute to the carcinogenesis of HCC. Although deletions and mutations in BRG1 gene were identified, the role of BRG1 in HCC tumourigenesis remains unclear.

Citation Format: Kohichiroh Yasui, Yasuyuki Gen, Akira Tomie, Tomoko Kitaichi, Yoshito Itoh. Reduced expression of BRM in hepatocellular carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5186. doi:10.1158/1538-7445.AM2014-5186

Abstract 3525: SOX2 promotes tumor growth via activation of the PI3K/Akt/mTORC1 signaling pathway in esophageal squamous cell carcinoma

Our previous study revealed that SOX2, a master regulator during embryogenesis, is an amplification target of 3q26.3 in esophageal squamous cell carcinoma (ESCC) and that SOX2 promotes ESCC cell proliferation. To identify the mechanisms by which SOX2 promotes proliferation of ESCC cells, we assayed multiple signaling pathways activated by SOX2 using a phosphoprotein array. We determined that SOX2 activated the AKT/mammalian target of rapamycin complex 1 (mTORC1) signaling pathway. Immunoblotting confirmed that SOX2 elevated levels of p-AKT and levels of p-p70S6K and p-4E-BP1 which are direct targets of mTORC1. Effects of SOX2 knockdown, including reduced levels of p-AKT and decreased ESCC cell viability, were reversed with constitutive activation of AKT with PTEN knockdown. SOX2 also promoted in vivo tumor growth of ESCC with AKT/mTORC1 activation in mouse xenografts. LY294002, a PI3K inhibitor, suppressed the ability of SOX2 to enhance tumor growth of ESCC by reducing cell proliferation. Furthermore, tissue microarray analysis showed a positive correlation between expression levels of SOX2 and p-AKT in 61 primary ESCC tumors. Our results suggest that SOX2 promotes ESCC tumor growth via activation of the PI3K/AKT / mTORC1 signaling pathway, which enhances cell proliferation.

Citation Format: Yasuyuki Gen, Kohichiroh Yasui, Tomoko Kitaichi, Akira Tomie, Yoshito Ito. SOX2 promotes tumor growth via activation of the PI3K/Akt/mTORC1 signaling pathway in esophageal squamous cell carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3525. doi:10.1158/1538-7445.AM2014-3525

L-menthol improves adenoma detection rate during colonoscopy: a randomized trial

BACKGROUND AND STUDY AIMS

Colonoscopy is one of the most reliable methods for the detection of colorectal neoplasms. However, colonic peristalsis during colonoscopy results in some neoplastic lesions being hidden from view and commonly requires an intravenous or intramuscular injection of antispasmodic agents, which may sometimes causes unexpected adverse reactions. The aim of this study was to evaluate the efficacy of L-menthol spray as an antiperistaltic agent and its effect on adenoma detection.

PATIENTS AND METHODS

This was a prospective, randomized, single-blind placebo-controlled trial. A total of 226 patients who were scheduled to undergo colonoscopy were randomly assigned to receive either 20 mL of 1.6 % L-menthol (n = 118) or placebo (n = 108). Both treatments were sprayed locally onto the colonic mucosa via an endoscope. The adenoma detection rate (ADR) and the proportion of patients with no peristalsis were the primary and secondary outcomes, respectively.

RESULTS

The ADR was significantly higher in the L-menthol group than in the placebo group (60.2 % vs. 42.6 %; P = 0.0083). The proportion of patients with no peristalsis after treatment with L-menthol was significantly higher than in the placebo group (71.2 % vs. 30.9 %; P < 0.0001). There were no adverse effects in either group.

CONCLUSIONS

The results suggest that the suppression of colonic peristalsis by L-menthol sprayed directly onto the colonic mucosa improves the ADR.

CLINICAL TRIAL REGISTRATION

ID: UMIN 000007972.

Endoscopic transgastric drainage of a gastric wall abscess after endoscopic submucosal dissection

A 63-year-old woman was referred to our hospital for further examination because of an incidental finding of early gastric cancer. Endoscopic submucosal dissection (ESD) was successfully performed for complete resection of the tumor. On the first post-ESD day, the patient suddenly complained of abdominal pain after an episode of vomiting. Abdominal computed tomography (CT) showed delayed perforation after ESD. The patient was conservatively treated with an intravenous proton pump inhibitor and antibiotics. On the fifth post-ESD day, CT revealed a gastric wall abscess in the gastric body. Gastroscopy revealed a gastric fistula at the edge of the post-ESD ulcer, and pus was found flowing into the stomach. An intradrainage stent and an extradrainage nasocystic catheter were successfully inserted into the abscess for endoscopic transgastric drainage. After the procedure, the clinical symptoms and laboratory test results improved quickly. Two months later, a follow-up CT scan showed no collection of pus. Consequently, the intradrainage stent was removed. Although the gastric wall abscess recurred 2 wk after stent removal, it recovered soon after endoscopic transgastric drainage. Finally, after stent removal and oral antibiotic treatment for 1 mo, no recurrence of the gastric wall abscess was found.

SOX2 promotes tumor growth of esophageal squamous cell carcinoma through the AKT/mammalian target of rapamycin complex 1 signaling pathway

The transcription factor SOX2 is essential for the maintenance of embryonic stem cells and normal development of the esophagus. Our previous study revealed that the SOX2 gene is an amplification target of 3q26.3 in esophageal squamous cell carcinoma (ESCC), and that SOX2 promotes ESCC cell proliferation in vitro. In the present study, we aimed to identify the mechanisms by which SOX2 promotes proliferation of ESCC cells. Using a phosphoprotein array, we assayed multiple signaling pathways activated by SOX2 and determined that SOX2 activated the AKT/mammalian target of rapamycin complex 1 (mTORC1) signaling pathway. LY294002, an inhibitor of phosphatidylinositol 3-kinase, and rapamycin, an inhibitor of mTORC1, suppressed the ability of SOX2 to enhance proliferation of ESCC cells in vitro. Effects of SOX2 knockdown, including reduced levels of phosphorylated AKT and decreased ESCC cell proliferation, were reversed with constitutive activation of AKT with knockdown of phosphatase and tensin homolog. In mouse xenografts, SOX2 promoted in vivo tumor growth of ESCC, which was dependent on AKT/mTORC1 activation. LY294002 suppressed the ability of SOX2 to enhance tumor growth of ESCC by reducing cell proliferation, but not by enhancing apoptosis. Furthermore, tissue microarray analysis of 61 primary ESCC tumors showed a positive correlation between expression levels of SOX2 and phosphorylated AKT. Our findings suggest that SOX2 promotes in vivo tumor growth of ESCC through activation of the AKT/mTORC1 signaling pathway, which enhances cell proliferation.

Aberrant expression of the PHF14 gene in biliary tract cancer cells

DNA copy number aberrations in human biliary tract cancer (BTC) cell lines were investigated using a high-density oligonucleotide microarray. A novel homozygous deletion was detected at chromosomal region 7p21.3 in the OZ cell line. Further validation experiments using genomic PCR revealed a homozygous deletion of a single gene, plant homeodomain (PHD) finger protein 14 (PHF14). No PHF14 mRNA or protein expression was detected, thus demonstrating the absence of PHF14 expression in the OZ cell line. Although the PHD finger protein is considered to be involved in chromatin-mediated transcriptional regulation, little is known about the function of PHF14 in cancer. The present study observed that the knock down of PHF14 using small interfering RNA (siRNA) enhanced the growth of the BTC cells. These observations suggest that aberrant PHF14 expression may have a role in the tumorigenesis of BTC.

Recognition of endoscopic diagnosis in differentiated-type early gastric cancer by flexible spectral imaging color enhancement with indigo carmine

BACKGROUND/AIMS

To evaluate the usefulness of flexible spectral imaging color enhancement with indigo carmine (I-FICE) in early gastric cancer (EGC) demarcation.

METHODS

The study participants were 29 patients with differentiated-type EGC. The endoscope was fixed and images of the same area of EGC demarcations in each lesion were obtained using four different methods (WLE, flexible spectral imaging color enhancement (FICE), CE, and I-FICE). FICE mode at R 550 nm (Gain: 2), G 500 nm (Gain: 4), and B 470 nm (Gain: 4) was used. Four endoscopists ranked the images obtained by each method on the basis of the ease of recognition of demarcation using a 4-point system. We calculated the standard deviation of pixel values based on L*, a*, and b* color spaces in the demarcation region (Lab-SD score).

RESULTS

The median ranking score for I-FICE images was significantly higher than that obtained from the other methods. Further, the average Lab-SD score was significantly higher for I-FICE images than for images obtained by the other methods. There was a good correlation between the ranking score and Lab-SD score.

CONCLUSION

EGC demarcations were most easily recognized both subjectively and objectively using I-FICE image, followed by CE, FICE and WLE images.

Alterations of the SWI/SNF chromatin remodelling subunit-BRG1 and BRM in hepatocellular carcinoma

BACKGROUND

The SWI/SNF chromatin remodelling complex, which contains either brahma-related gene-1 (BRG1) or brahma (BRM) as the catalytic ATPase, functions as a master regulator of gene expression.

AIMS

To examine alterations of BRG1 and BRM in hepatocellular carcinoma (HCC).

METHODS

We investigated DNA copy number aberrations in human HCC cell lines using a high-density oligonucleotide microarray. We determined DNA copy numbers and expression levels of BRG1 and BRM genes in primary HCC tumours, and conducted further searches for mutations in BRG1 and BRM genes.

RESULTS

Homozygous deletion of the BRG1 gene was found in HCC cell line SNU398. Copy number losses of BRG1 and BRM genes were observed in 14 (26%) and 7 (13%) of 54 primary HCC tumours respectively. We found four somatic missense mutations in the BRG1 gene in two of 36 primary HCC tumours, but no mutations in BRM gene. Expression of BRM mRNA, but not BRG1 mRNA, was significantly reduced in primary HCC tumours, compared to non-tumour tissue counterparts. Immunohistochemical analyses of non-tumour liver tissues showed that BRM protein was expressed in hepatocytes and bile-duct epithelial cells, whereas BRG1 protein was expressed in bile-duct epithelial cells, but not in hepatocytes. BRM protein expression was lost in nine (22.5%) of 40 HCC tumours. Loss of BRM protein expression was significantly associated with poor overall survival.

CONCLUSION

Reduced expression of BRM may contribute to the carcinogenesis of HCC. Although deletions and mutations in BRG1 gene were identified, the role of BRG1 in HCC tumourigenesis remains unclear.

Epigenetic silencing of miR-335 and its host gene MEST in hepatocellular carcinoma

MicroRNAs (miRNAs) are small non-coding RNAs that function as endogenous silencers of target genes. Some tumor-suppressive miRNAs are known to be epigenetically silenced by promoter DNA methylation in cancer. In the present study, we aimed to identify miRNA genes that are silenced by DNA hypermethylation in hepatocellular carcinoma (HCC). We screened for miRNA genes with promoter DNA hypermethylation using a genome-wide methylation microarray analysis in HCC cells. It was found that miR-335, which is harbored within an intron of its protein-coding host gene, MEST, was downregulated by aberrant promoter hypermethylation via further methylation assays, including methylation-specific PCR, combined bisulfite and restriction analysis, bisulfite sequencing analysis and 5-aza-2′-deoxycytidine treatment. The expression levels of miR-335 significantly correlated with those of MEST, supporting the notion that the intronic miR-335 is co-expressed with its host gene. The levels of miR-335/MEST methylation were significantly higher in 18 (90%) out of 20 primary HCC tumors, compared to their non-tumor tissue counterparts (P<0.001). The expression levels of miR-335 were significantly lower in 25 (78%) out of 32 primary HCC tumors, compared to their non-tumor tissue counterparts (P=0.001). Furthermore, the expression levels of miR-335 were significantly lower in HCC tumors with distant metastasis compared to those without distant metastasis (P=0.02). In conclusion, our results indicate that expression of miR-335 is reduced by aberrant DNA methylation in HCC.

SOX2 identified as a target gene for the amplification at 3q26 that is frequently detected in esophageal squamous cell carcinoma

SOX2 is a transcription factor with a high-mobility group DNA-binding domain that functions as a master regulator during embryogenesis and organogenesis. We investigated DNA copy number aberrations in esophageal squamous cell carcinoma (ESCC) cell lines using a high-density oligonucleotide microarray and found frequent amplification at the chromosomal region 3q26. The estimated extent of the minimal overlapping region of amplification was 1.3 Mb. This chromosomal region includes a single gene, SOX2. The SOX2 protein was overexpressed in cell lines in which the gene was amplified. Knockdown experiments showed that SOX2 promotes proliferation of ESCC cells. Genes potentially modulated by SOX2 were determined by expression array analyses combined with small interfering RNA cell-transfection studies. A copy number gain of SOX2 (>2-fold) was observed in 6 of the 40 primary ESCCs (15%). Immunohistochemical study revealed that expression of the SOX2 protein was significantly elevated in 62 of the 89 ESCC tumors (70%), compared with their nontumorous counterparts, and that upregulated expression of SOX2 was associated with poor differentiation of ESCC. Our results suggest that SOX2 is likely to be a target of the 3q26 amplification and may therefore be involved in the development or progression of ESCC.

PEG10 is a probable target for the amplification at 7q21 detected in hepatocellular carcinoma

DNA copy number aberrations in human hepatocellular carcinoma (HCC) cell lines were investigated using a high-density oligonucleotide microarray, and a novel amplification at the chromosomal region 7q21 was detected. Molecular definition of the amplicon indicated that PEG10 (paternally expressed gene 10), a paternally expressed imprinted gene, was amplified together with CDK14 (cyclin-dependent kinase 14; previously PFTAIRE protein kinase 1, PFTK1) and CDK6 (cyclin-dependent kinase 6). An increase in PEG10 copy number was detected in 14 of 34 primary HCC tumors (41%). PEG10, but not CDK14 or CDK6, was significantly overexpressed in 30 of 41 tumors (73%) from HCC patients, compared with their nontumorous counterparts. These results suggest that PEG10 is a probable target, acting as a driving force for amplification of the 7q21 region, and may therefore be involved in the development or progression of HCCs.

Infrequent amplification of JUN in hepatocellular carcinoma

AIM

To determine whether JUN (the oncogene encoding c-Jun protein) is amplified and overexpressed in hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

DNA copy number aberrations were investigated using a high-density oligonucleotide microarray. DNA copy numbers were determined by fluorescence in situ hybridization. Genomic DNA and mRNA were quantified using real-time quantitative PCR.

RESULTS

A novel amplification was found at the chromosomal region 1p32-31 in a JHH-2 HCC cell line within which JUN is amplified and overexpressed. However, no copy number gain of JUN (>2-fold) was observed in 34 primary HCC tumors. Rather, a loss of JUN (<0.5-fold) was seen in 13 (38%) out of the 34 tumors and expression of JUN was significantly lower in 26 (70%) out of the 37 HCC tumors compared with their nontumorous counterparts.

CONCLUSION

Although JUN was amplified and overexpressed in JHH-2 HCC cells, amplification and overexpression of JUN may be rare in primary HCCs.

A novel amplification target, ARHGAP5, promotes cell spreading and migration by negatively regulating RhoA in Huh-7 hepatocellular carcinoma cells

RhoA, a member of the Rho family of small GTPases, directs the organization of the actin cytoskeleton and is involved in regulating cell shape and movement. Its activity is negatively regulated by p190-B RhoGAP (GTPase-activating protein). We investigated DNA copy number aberrations in human hepatocellular carcinoma and esophageal squamous cell carcinoma cell lines using a high-density oligonucleotide microarray and found a novel amplification at chromosomal region 14q12. We identified ARHGAP5 (the gene encoding p190-B RhoGAP) as a probable target for the amplification at 14q12, and our results showed that p190-B RhoGAP promotes cells spreading and migration by negatively regulating RhoA activity in Huh-7 hepatocellular carcinoma cells.

[Successful treatment for advanced hepatocellular carcinoma by hepatic arterial infusion of CDDP powder as second-line chemotherapy]

A 72-year-old man with type C liver cirrhosis had suffered from hepatocellular carcinoma (HCC) since April, 2001. HCC spread diffusely all over the right lobe of his liver, and the serum alpha-fetoprotein (AFP) value increased up to 42,696 ng/ml in June of 2004. He was implanted with a port-catheter system, and hepatic arterial infusion chemotherapy (HAIC) using low-dose of CDDP and 5-FU was started. However, it was not effective and after 4 months, the serum AFP level increased up to 755,030 ng/ml, ascites appeared, and gastro-esophageal varices also spread. No definite metastasis was detected, then we started to second-line chemotherapy. He was then given HAIC using CDDP powder for intraarterial use (CDDP 50 mg/m(2)/20 min, monthly). After 3 courses, the serum AFP level decreased to 9 10 ng/ml, and abdominal CT revealed that the main tumor had regressed and ascites had disappeared. After one more course, the serum AFP value decreased to 8 ng/ml and complete response was achieved on abdominal CT imaging. There was no major complication related to the chemotherapy. HAIC for advanced HCC using LFP has been reported to achieve favorable results, but no other regimens have been proved to the standard for HCC. HAIC using CDDP powder for advanced HCC may be beneficial as the second-line chemotherapy.