Lansoprazole inhibits the development of sessile serrated lesions by inducing G1 arrest via Skp2/p27 signaling pathway

BACKGROUND

Although the serrated-neoplasia pathway reportedly accounts for 15-30% of colorectal cancer (CRC), no studies on chemoprevention of sessile serrated lesions (SSLs) have been reported. We searched for effective compounds comprehensively from a large series of compounds by employing Connectivity Map (CMAP) analysis of SSL-specific gene expression profiles coupled with in vitro screening using SSL patient-derived organoids (PDOs), and validated their efficacy using a xenograft mouse model of SSL.

METHODS

We generated SSL-specific gene signatures based on DNA microarray data, and applied them to CMAP analysis with 1309 FDA-approved compounds to select candidate compounds. We evaluated their inhibitory effects on SSL-PDOs using a cell viability assay. SSL-PDOs were orthotopically transplanted into NOG mice for in vivo evaluation. The signal transduction pathway was evaluated by gene expression profile and protein expression analysis.

RESULTS

We identified 221 compounds by employing CMAP analysis of SSL-specific signatures, which should cancel the gene signatures, and narrowed them down to 17 compounds. Cell viability assay using SSL-PDOs identified lansoprazole as having the lowest IC50 value (47 µM) among 17 compounds. When SSL-PDO was orthotopically transplanted into murine intestinal tract, the tumor grew gradually. Administration of lansoprazole to mice inhibited the growth of SSL xenograft whereas the tumor in control mice treated with vehicle alone grew gradually over time. The Ki67 index in xenograft lesions from the lansoprazole group was significantly lower compared with the control group. Cell cycle analysis of SSL-PDOs treated with lansoprazole exhibited a significant increase in G1 phase cell population. Microarray and protein analysis revealed that lansoprazole downregulated Skp2 expression and upregulated p27 expression in SSL-PDOs.

CONCLUSIONS

Our data strongly suggest that lansoprazole is the most effective chemopreventive agent against SSL, and that lansoprazole induces G1 cell cycle arrest by downregulating Skp2 and upregulating p27 in SSL cells.

Clinical Guidelines for Diagnosis and Management of Cowden Syndrome/PTEN Hamartoma Tumor Syndrome in Children and Adults-Secondary Publication

Cowden syndrome (CS)/PTEN hamartoma tumor syndrome (PHTS) is a rare autosomal dominantly inherited condition caused by germline pathogenesis. It is associated with multiple hamartomatous lesions occurring in various organs and tissues, including the gastrointestinal tract, skin, mucous membranes, breast, thyroid, endometrium, and brain. Macrocephaly or multiple characteristic mucocutaneous lesions commonly develop in individuals in their 20s. This syndrome is occasionally diagnosed in childhood due to the occurrence of multiple gastrointestinal polyps, autism spectrum disorders, and intellectual disability. CS/PHTS can be diagnosed taking the opportunity of multigene panel testing in patients with cancer. Appropriate surveillance for early diagnosis of associated cancers is required because patients have a high risk of cancers including breast, thyroid, colorectal, endometrial, and renal cancers. Under these circumstances, there is growing concern regarding the management of CS/PHTS in Japan, but there are no available practice guidelines. To address this situation, the guideline committee, which included specialists from multiple academic societies, was organized by the Research Group on Rare and Intractable Diseases granted by the Ministry of Health, Labour, and Welfare, Japan. The present clinical guidelines explain the principles in the diagnosis and management of CS/PHTS, together with four clinical questions and the corresponding recommendations, incorporating the concept of the Grading of Recommendations Assessment, Development, and Evaluation system. Herein, we present an English version of the guideline, some of which have been updated, to promote seamless implementation of accurate diagnosis and appropriate management of pediatric, adolescent, and adult patients with CS/PHTS.

Risk Factors Related to Severity in COVID-19 Patients: A Real-world Retrospective Cohort Study

Objective Understanding the clinical factors associated with the severity of coronavirus disease 2019 (COVID-19) is very important for the effective use of limited medical resources, including the appropriate evaluation of the need for hospitalization and discharge. Methods Patients hospitalized with a diagnosis of COVID-19 from March 2021 to October 2022 were included in the study. Patients admitted to our facility were classified into four waves: 4th (April to June 2021), 5th (July to October 2021), 6th (January to June 2022), and 7th waves (July to October 2022). We analyzed the severity, patients' background characteristics, presence of pneumonia on chest computed tomography (CT), and blood test results in each wave. Patients were further classified into respiratory failure and nonrespiratory failure groups and statistically compared. Results Of the 565 patients diagnosed with COVID-19, 546 were included in this study. The percentage of patients classified as mild was approximately 10% in the 4th and 5th waves, but the rate increased after the 6th wave, with rates of 55.7% and 54.8% in each wave. Although more than 80% of patients in the 4th and 5th waves showed pneumonia on chest CT, the percentage decreased to approximately 40% after the 6th wave. Further comparisons between the respiratory failure group (n=75) and the nonrespiratory failure group (n=471) revealed significant differences in the age, sex, vaccination history, and biomarker values between the two groups. Conclusion In this study, elderly men were found to be more likely to develop severe disease than others, and biomarkers of COVID-19, such as C-reactive protein and lactate dehydrogenase, were useful for predicting severity. This study also suggested that vaccination may have contributed to a reduced disease severity.

1,3a,6a-Triazapentalene derivatives as photo-induced cytotoxic small fluorescent dyes

1,3a,6a-Triazapentalene (TAP) is a compact fluorescent chromophore whose fluorescence properties vary greatly depending on the substituents on the TAP ring. This study investigated the photo-induced cytotoxicities of various TAP derivatives. Among the derivatives, 2-p-nitrophenyl-TAP showed significant cytotoxicity to HeLa cells under UV irradiation but no cytotoxicity without UV. In addition, the photo-induced cytotoxicity of 2-p-nitirophenyl-TAP was found to be cancer cell selective and effective against HeLa cells and HCT 116 cells. Under UV irradiation, 2-p-nitrophenyl-TAP generated reactive oxygen species (ROS) that induced an apoptosis and ferroptosis in cancer cells. Therefore, it was revealed that 2-p-nitrophenyl-TAP is the most compact dye that can generate ROS by photoirradiation.

Resveratrol inhibits development of colorectal adenoma via suppression of LEF1; comprehensive analysis with connectivity map

Although many chemopreventive studies on colorectal tumors have been reported, no effective and safe preventive agent is currently available. We searched for candidate preventive compounds against colorectal tumor comprehensively from United States Food and Drug Administration (FDA)-approved compounds by using connectivity map (CMAP) analysis coupled with in vitro screening with colorectal adenoma (CRA) patient-derived organoids (PDOs). We generated CRA-specific gene signatures based on the DNA microarray analysis of CRA and normal epithelial specimens, applied them to CMAP analysis with 1309 FDA-approved compounds, and identified 121 candidate compounds that should cancel the gene signatures. We narrowed them down to 15 compounds, and evaluated their inhibitory effects on the growth of CRA-PDOs in vitro. We finally identified resveratrol, one of the polyphenolic phytochemicals, as a compound showing the strongest inhibitory effect on the growth of CRA-PDOs compared with normal epithelial PDOs. When resveratrol was administered to Apc^Min/+ mice at 15 or 30 mg/kg, the number of polyps (adenomas) was significantly reduced in both groups compared with control mice. Similarly, the number of polyps (adenomas) was significantly reduced in azoxymethane-injected rats treated with 10 or 100 mg/resveratrol compared with control rats. Microarray analysis of adenomas from resveratrol-treated rats revealed the highest change (downregulation) in expression of LEF1, a key molecule in the Wnt signaling pathway. Treatment with resveratrol significantly downregulated the Wnt-target gene (MYC) in CRA-PDOs. Our data demonstrated that resveratrol can be the most effective compound for chemoprevention of colorectal tumors, the efficacy of which is mediated through suppression of LEF1 expression in the Wnt signaling pathway.

Initial therapeutic results of atezolizumab plus bevacizumab for unresectable advanced hepatocellular carcinoma and the importance of hepatic functional reserve

AIM

We analyzed the association between the modified albumin-bilirubin (mALBI) grade and therapeutic efficacy of atezolizumab plus bevacizumab (Atezo+Bev) for the treatment of unresectable hepatocellular carcinoma (u-HCC).

METHODS

In this retrospective observational study, we included 71 u-HCC patients treated with Atezo+Bev between September 2020 and September 2021. Patients were grouped corresponding to the mALBI grade at the start of treatment (mALBI 1+2a or mALBI 2b+3) and analyzed for therapeutic effect and the transition rate to secondary treatment.

RESULTS

According to the Response Evaluation Criteria in Solid Tumors, the overall response rate was significantly higher for the mALBI 1+2a group, than for the mALBI 2b+3 group, with 26.2% and 3.4%, respectively. The progression-free survival (PFS) was significantly longer in the mALBI 1+2a group (10.5 months) than in the mALBI 2b+3 group (3.0 months). In the multivariate analysis, an mALBI of 1+2a was found to be an independent factor of PFS. The rate of second-line treatment with multi-targeted agents was also significantly higher in the mALBI 1+2a group.

CONCLUSIONS

In real-world practice, Atezo+Bev treatment might have higher therapeutic efficacy in u-HCC patients with mALBI 1+2a.

Pulmonary Tumor Thrombotic Microangiopathy Due to Gastric Cancer Diagnosed Antemortem by a Cytological Examination of Aspirated Pulmonary Artery Blood

A 66-year-old Japanese man receiving systemic chemotherapy for advanced gastric cancer presented with exertional dyspnea. D-dimer was elevated in the blood. Echocardiography revealed pulmonary hypertension, and a ventilation-perfusion scan indicated decreased perfusion in the bilateral lungs. Cardiac catheterization showed no evidence of pulmonary artery embolization and revealed cytologically confirmed adenocarcinoma. Thus, pulmonary tumor thrombotic microangiopathy (PTTM) was diagnosed. The patient died of respiratory failure on the 17th hospitalization day despite systemic chemotherapy. Retrospective serological testing revealed increased vascular endothelial growth factor in the pulmonary artery blood. This is a rare case with antemortem cytologically proven PTTM mediated by VEGF.

miR-144-3p/miR-451a promotes lymphovascular invasion through repression of PTEN/p19 in rectal neuroendocrine tumors

BACKGROUND AND AIM

Although rectal neuroendocrine tumor (NET-G1) have potential metastatic capability, even among small tumors, no predictive biomarker for invasion and metastasis has been reported. We analyzed microRNA (miRNA) expression profiles in rectal NET-G1 tissues with and without lymphovascular invasion (LVI). Moreover, we then investigated their target genes to clarify the mechanism of invasion/metastasis in NET-G1.

METHODS

miRNA array analysis was performed using seven rectal NET-G1 tissues with LVI and seven without LVI. miRNA expression was confirmed by quantitative real-time PCR. A NET cell line H727 was transfected with miRNA mimic or target gene small interfering RNA, and migration and invasion assays were performed.

RESULTS

The expression levels of miR-144-3p and miR-451a were significantly higher in NET-G1 with LVI versus without LVI, as determined by miRNA array analysis and RT-qPCR. A significant correlation was observed between miR-144-3p and miR-451a expression levels, strongly suggesting miR144/451 cluster overexpression in NET-G1 with LVI. Bioinformatic analysis of target genes revealed that miR-144-3p and miR-451a directly interact with PTEN and p19 mRNA, respectively. Immunohistochemistry revealed significantly lower expression of PTEN and p19 in NET-G1 tissues with LVI than in those without LVI. The miR-144-3p and miR-451a mimic significantly increased cell migration/invasion capability, respectively. Knockdown of PTEN and p19 induced significant augmentation of cell invasion and migration capability, respectively.

CONCLUSIONS

Our data suggest that overexpression of miR-144/miR-451 cluster promotes LVI via repression of PTEN and p19 in rectal NET-G1 cells. miR-144/451 cluster may be a novel biomarker for predicting invasion/metastasis in rectal NET-G1.

Cancer risk and genotype-phenotype correlation in Japanese patients with Cowden syndrome

BACKGROUND

Cowden syndrome (CS) is an autosomal-dominant hereditary disorder caused by a germline PTEN variant and characterized by multiple hamartomas and a high risk of cancers. However, no detailed data on CS in Asian patients nor genotype-phenotype correlation have been reported.

METHODS

We performed the first Japanese nationwide questionnaire survey on CS and obtained questionnaire response data on 49 CS patients.

RESULTS

Patients included 26 females (median age 48 years). The incidence of breast, thyroid, endometrium, and colorectal cancer was 32.7%, 12.2%, 19.2% (among females), and 6.1%, respectively. The incidence of any cancers was relatively high among all patients (46.9%, 23/49), and particularly female patients (73.1%, 19/26), compared with previous reports from Western countries. Gastrointestinal (GI) polyps were more frequently found throughout the GI tract compared with previous studies. PTEN variants were detected in 95.6% (22/23) of patients; 12 in the N-terminal region (11 in phosphatase domain) and 10 in the C-terminal (C2 domain) region. The incidence of cancer in the C2 domain group was significantly higher than in the N-terminal region (phosphatase) group. All female patients with C2 domain variant had breast cancer.

CONCLUSION

Our data suggest that Japanese patients with CS, particularly female patients and patients with C2 domain variant may have a high risk of cancers.

Therapeutic efficacy of lenvatinib in nonviral unresectable hepatocellular carcinoma

Aim

To investigate the therapeutic effect of lenvatinib (LEN) in liver disease etiology, especially nonviral hepatocellular carcinoma (HCC).

Methods and Results

Sixty‐seven patients with unresectable advanced HCC (u‐HCC) treated with LEN and consisting of 26 hepatitis C virus (HCV), 19 hepatitis B virus (HBV), 11 alcohol, and 11 nonalcoholic steatohepatitis (NASH) cases were retrospectively recruited. Univariate and multivariate Cox proportional hazard models were used to determine predictive factors for survival. The objective response rate in the nonviral (alcohol and NASH) group was higher than that in the viral group (59.1% [13/22] vs. 46.7% [21/45]). Progression‐free survival was significantly longer in the nonviral group than in the viral group (13.7 vs. 6.6 months; hazard ratio [HR] 0.324; 95% confidence interval [CI] 0.174–0.602; P < 0.01). Similarly, median overall survival (OS) was significantly longer in the nonviral group than in the viral group (not evaluable vs. 15.9 months; HR = 0.277; 95% CI = 0.116–0.662; P < 0.01). Multivariate analysis revealed that portal vein invasion (HR = 5.327, P = 0.0025), treatment line (HR = 0.455, P = 0.023), and etiology (HR = 0.180, P = 0.00055) were significant independent factors associated with OS in u‐HCC patients treated with LEN.

Conclusion

Our results suggest that LEN is more effective against nonviral u‐HCC than against viral u‐HCC.

Clinicopathological characteristics of early gastric cancer associated with autoimmune gastritis

Background

Autoimmune gastritis is known to be associated with neoplastic lesions but the relationship between autoimmunity and tumorigenesis have not been sufficiently clarified. The aim of this study is to assess the clinicopathological characteristics of gastric cancer cases associated with autoimmune gastritis.

Methods

A total of 24 patients diagnosed as early gastric cancer with autoimmune gastritis were registered. Chart reviews with the data including age, gender, state of Helicobacter pylori infection, comorbidity, and concomitant gastric diseases were conducted. As for the characteristics of gastric cancer, location, size, morphological type, histopathology, invasion depth, and the presence of metachronous or simultaneous lesion were assessed. These data from autoimmune gastritis group were compared with those from 301 patients of early gastric cancer as a control group.

Results

The gastric cancer associated with autoimmune gastritis was located in the upper, middle, and lower parts in 28.1%, 53.1%, and 18.8%, respectively. The morphological types are as follows: 0‐I, 9.4%; 0‐IIa, 28.1%; 0‐IIb, 15.6%; 0‐IIc, 46.9%; and 0‐III, 0.0%. The mean tumor size was 21.8 mm. While 90.6% were confined to the mucosa, 9.4% showed submucosal invasion. The histological classifications are as follows: tub1, 50.0%; tub2, 15.6%; pap, 21.9%; sig, 9.4%; and por, 3.1%. More numbers of female, protruded types, larger tumor size, papillary tumor, and that in the upper location were observed in autoimmune gastritis group compared to control group.

Conclusion

Early gastric cancer associated with autoimmune gastritis demonstrated different characteristics from those without autoimmune gastritis including variety of tumor morphologies and histological types with female dominancy.

MiR-125b-5p Is Involved in Sorafenib Resistance through Ataxin-1-Mediated Epithelial-Mesenchymal Transition in Hepatocellular Carcinoma

The mechanism of resistance to sorafenib in hepatocellular carcinoma (HCC) remains unclear. We analyzed miRNA expression profiles in sorafenib-resistant HCC cell lines (PLC/PRF5-R1/R2) and parental cell lines (PLC/PRF5) to identify the miRNAs responsible for resistance. Drug sensitivity, migration/invasion capabilities, and epithelial-mesenchymal transition (EMT) properties were analyzed by biochemical methods. The clinical relevance of the target genes to survival in HCC patients were assessed using a public database. Four miRNAs were significantly upregulated in PLC/PRF5-R1/-R2 compared with PLC/PRF5. Among them, miR-125b-5p mimic-transfected PLC/PRF5 cells (PLC/PRF5-miR125b) and showed a significantly higher IC50 for sorafenib compared with controls, while the other miRNA mimics did not. PLC/PRF5-miR125b showed lower E-cadherin and higher Snail and vimentin expression-findings similar to those for PLC/PRF5-R2-which suggests the induction of EMT in those cells. PLC/PRF5-miR125b exhibited significantly higher migration and invasion capabilities and induced sorafenib resistance in an in vivo mouse model. Bioinformatic analysis revealed ataxin-1 as a target gene of miR-125b-5p. PLC/PRF5 cells transfected with ataxin-1 siRNA showed a significantly higher IC50, higher migration/invasion capability, higher cancer stem cell population, and an EMT phenotype. Median overall survival in the low-ataxin-1 patient group was significantly shorter than in the high-ataxin-1 group. In conclusion, miR-125b-5p suppressed ataxin-1 and consequently induced Snail-mediated EMT and stemness, leading to a poor prognosis in HCC patients.

S100P Expression via DNA Hypomethylation Promotes Cell Growth in the Sessile Serrated Adenoma/Polyp-Cancer Sequence

BACKGROUND/AIMS

Sessile serrated adenomas/polyps (SSA/Ps) are a putative precursor lesion of colon cancer. Although the relevance of DNA hypermethylation in the SSA/P-cancer sequence is well documented, the role of DNA hypomethylation is unknown. We investigated the biological relevance of DNA hypomethylation in the SSA/P-cancer sequence by using 3-dimensional organoids of SSA/P.

METHODS

We first analyzed hypomethylated genes using datasets from our previous DNA methylation array analysis on 7 SSA/P and 2 cancer in SSA/P specimens. Expression levels of hypomethylated genes in SSA/P specimens were determined by RT-PCR and immunohistochemistry. We established 3-dimensional SSA/P organoids and performed knockdown experiments using a lentiviral shRNA vector. DNA hypomethylation at CpG sites of the gene was quantitated by MassARRAY analysis.

RESULTS

The mean number of hypomethylated genes in SSA/P and cancer in SSA/P was 41.6 ± 27.5 and 214 ± 19.8, respectively, showing a stepwise increment in hypomethylation during the SSA/P-cancer sequence. S100P, S100α2, PKP3, and MUC2 were most commonly hypomethylated in SSA/P specimens. The mRNA and protein expression levels of S100P, S100α2, and MUC2 were significantly elevated in SSA/P compared with normal colon tissues, as revealed by RT-PCR and immunohistochemistry, respectively. Among these, mRNA and protein levels were highest for S100P. Knockdown of the S100P gene using a lentiviral shRNA vector in 3-dimensional SSA/P organoids inhibited cell growth by >50% (p < 0.01). The mean diameter of SSA/P organoids with S100P gene knockdown was significantly smaller compared with control organoids. MassARRAY analysis of DNA hypomethylation in the S100P gene revealed significant hypomethylation at specific CpG sites in intron 1, exon 1, and the 5'-flanking promoter region.

CONCLUSION

These results suggest that DNA hypomethylation, including S100P hypomethylation, is supposedly associated with the SSA/P-cancer sequence. S100P overexpression via DNA hypomethylation plays an important role in promoting cell growth in the SSA/P-cancer sequence.

Long-Term Survival due to Chemotherapy including Paclitaxel in a Patient with Metastatic Primary Splenic Angiosarcoma

A primary splenic angiosarcoma is a rare type of soft tissue sarcoma and is associated with an extremely poor prognosis. In this study, we describe the case of a patient who was diagnosed with metastatic primary splenic angiosarcoma and survived for about 2 years. A 62-year-old female was referred to us for the treatment of splenic angiosarcoma with disseminated intravascular coagulation (DIC) and multiple liver and bone metastases. Paclitaxel therapy resulted in recovery from DIC and enabled her to continue sequential treatment through to sixth-line chemotherapy. We reviewed all splenic angiosarcoma case reports which were described as stage IV to date and compared with our case. From these data, we found that the median overall survival was 105 days, and the prognosis of splenic angiosarcoma of stage IV was worse than conventional case series. Splenectomy was performed in more patients than chemotherapy as a treatment. Moreover, various chemotherapeutic regimens were used. These data suggest that administering chemotherapy including paclitaxel to patients with splenic angiosarcoma might improve their prognosis.

Recent Advances in Molecular Imaging of Colorectal Tumors

BACKGROUND

Recent endoscopic studies have revealed that small colorectal tumors are often overlooked during colonoscopy, indicating that more sensitive detection methods are needed.

SUMMARY

Molecular imaging has received considerable attention as a new endoscopic technique with high sensitivity. It generally employs a fluorescence-labeled compound that specifically binds to a molecule on the tumor. Fluorescent probes for molecular imaging are largely classified as 2 types: a fluorescence-labeled antibody targeting a molecule specifically expressed on the tumor cell surface such as epidermal growth factor receptor or vascular endothelial growth factor (VEGF); and a fluorescence-labeled small molecule compound targeting a molecule specifically expressed in tumor cells including c-Met, glutathione S-transferase, γ-glutamyltranspeptidase, cathepsin, or endothelin A receptor. These probes successfully detected colorectal tumors in several animal studies. Moreover, 3 recent human clinical trials evaluating endoscopic molecular imaging for colorectal tumors have been reported. In one study, a Cy5-labeled synthetic peptide against c-Met was developed, and fluorescent endoscopic observation with this probe detected a greater number of colorectal adenomas than with white light observation. Another trial used IR800-labeled anti-VEGF antibody, which sensitively detected human colorectal adenomas by fluorescent endoscopy. Last, a fluorescent probe with synthetic peptide against BRAF-positive cells was able to visualize sessile serrated lesions. The fluorescent probes accumulated at very high levels in colorectal tumor cells but at lower levels in surrounding nonneoplastic mucosa. Key Messages: We expect that molecular imaging techniques with fluorescent probes will soon lead to the establishment of a highly sensitive endoscopic method for colorectal tumor detection.

MicroRNA-296-5p Promotes Cell Invasion and Drug Resistance by Targeting Bcl2-Related Ovarian Killer, Leading to a Poor Prognosis in Pancreatic Cancer

BACKGROUND/AIMS

Pancreatic ductal adenocarcinoma (PDAC) is characterized by aggressive invasion, early metastasis, and resistance to chemotherapy, leading to a poor prognosis. To clarify the molecular mechanism of these malignant characteristics, we performed a genome-wide microRNA (miRNA) array analysis utilizing micro-cancer tissues from patients with unresectable PDAC (stage IV), obtained by endoscopic ultrasound-fine needle aspiration (EUS-FNA).

METHODS

The expression profiles of 2,042 miRNAs were determined using micro-cancer tissues from 13 patients with unresectable PDAC obtained by EUS-FNA. The relationship between individual miRNA levels and overall survival (OS) was analyzed. Possible target genes for miRNAs were bioinformatically analyzed using the online database miRDB. Pancreatic cancer cell lines PANC-1, MIA PaCa-2, and PK-8 were transfected with miRNA mimic or small interfering RNA, and cell invasion, epithelial-mesenchymal transition (EMT), and apoptosis markers were examined. miRNA and mRNA expressions were examined by quantitative polymerase chain reaction.

RESULTS

Of 2,042 miRNAs, the 10 that exhibited the lowest correlation coefficient (p ≤ 0.005) between miRNA expression level and OS among the patients were identified. The miRDB and expression analysis in cancer cell lines for the 10 miRNAs identified miR-296-5p and miR-1207-5p as biomarkers predictive of shorter survival (p < 0.0005). Bioinformative target gene analysis and transfection experiments with miRNA mimics showed that Bcl2-related ovarian killer (BOK), a pro-apoptotic gene, is a target for miR296-5p in pancreatic cancer cells; transfection of miR-296-5p mimic into PANC-1, MIA PaCa-2, and PK-8 cells resulted in significant suppression of BOK mRNA and protein expression. These transfectants showed significantly higher invasion capability compared with control cells, and knock down of BOK in pancreatic cancer cells similarly enhanced invasion capability. Transfectants of miR-296-5p mimic also exhibited aberrant expression of EMT markers, including vimentin and N-cadherin. Moreover, these transfectants showed a significantly lower apoptosis rate in response to 5-fluorouracil and gemcitabine with a decrease of BOK expression, suggesting a role of miR-296-5p in drug resistance.

CONCLUSION

These results suggest that miR-296-5p is a useful biomarker for a poor prognosis in patients with PDAC, and that the miR-296-5p/BOK signaling axis plays an important role in cell invasion, drug resistance, and EMT in PDACs.

An Adult Case of Congenital Extrahepatic Portosystemic Shunt Successfully Treated with Balloon-occluded Retrograde Transvenous Obliteration

A 42-year-old woman visited our hospital due to syncope. Contrast-enhanced CT revealed portosystemic shunt, portal vein hypoplasia, and multiple liver nodules. The histological examination of a liver biopsy specimen exhibited portal vein hypoplasia and revealed that the liver tumor was positive for glutamine synthetase. The patient was therefore diagnosed with congenital extrahepatic portosystemic shunt type II, and with focal nodular hyperplasia (FNH)-like nodules. She had the complication of severe portopulmonary hypertension and underwent complete shunt closure by balloon-occluded retrograde transvenous obliteration (B-RTO). The intrahepatic portal vein was well developed at 1 year after B-RTO, and multiple liver nodules completely regressed. Her pulmonary hypertension also improved.

[A case of hemolysis and acute kidney disease caused by rectal damage due to glycerin enema]

A male patient in his sixties with a long-term history of schizophrenia had been received glycerin enema once or twice a week in a mental hospital. He was emergently transferred to our hospital due to fever, vomiting, hematuria, and dyspnea. Laboratory findings on admission showed an elevation of white blood cells indicating inflammation, hemolysis, and renal dysfunction. Plain CT showed pleural effusion and ascites, elevated levels of perirectal fat, in addition to extraintestinal gas. Based on these findings, he was diagnosed with rectal damage caused by the glycerin enema and associated hemolysis with acute renal failure. He was kept under conditions of nil by mouth and received intravenous antibiotics, diuretic drug, and haptoglobin. Eventually, his condition improved with these conservative therapies. In this case, it is assumed that the hemolysis was caused by the influx of glycerin in the cytoplasm and an increase of osmotic pressure. Care should be taken during glycerin enema, which is widely used in daily practice as well as in home care settings.

Indocyanine green-labeled dasatinib as a new fluorescent probe for molecular imaging of gastrointestinal stromal tumors

BACKGROUND AND AIM

It is difficult to differentiate gastrointestinal stromal tumors (GISTs) from other subepithelial lesions under gastrointestinal endoscopy. Because most GISTs express tyrosine kinase receptor c-KIT, fluorescence-labeled c-KIT-specific tyrosine kinase inhibitors seem to be useful agents for molecular imaging of GIST. We aimed to develop a near-infrared fluorescent imaging technology for GIST targeting c-KIT using the novel fluorescent probe indocyanine green-labeled dasatinib (ICG-dasatinib) and to investigate the antitumor effect of ICG-dasatinib on GIST cells.

METHODS

Indocyanine green-labeled dasatinib was synthesized by labeling linker-induced dasatinib with ICG derivative 3-indocyanine-green-acyl-1,3-thiazolidine-2-thione. Human GIST cell lines GIST-T1 and GIST-882M were incubated with ICG-dasatinib and observed by fluorescent microscopy. GIST cells were incubated with ICG-dasatinib, unlabeled dasatinib, or imatinib, and cell viabilities were evaluated. Subcutaneous GIST model mice or orthotopic GIST model rats were intravenously injected with ICG-dasatinib and observed using an IVIS Spectrum.

RESULTS

Strong fluorescent signals of ICG-dasatinib were observed in both GIST cell lines in vitro. IC50 values for ICG-dasatinib, unlabeled dasatinib, and imatinib were 13.9, 1.17, and 16.2 nM in GIST-T1 and 26.6, 3.63, and 47.6 nM in GIST-882M cells, respectively. ICG-dasatinib accumulated in subcutaneous xenografts in mice. Fluorescent signals were also observed in liver and gallbladder, indicating biliary excretion; however, fluorescence intensity of tumors was significantly higher than that of intestine after washing. Strong fluorescent signals were observed in orthotopic xenografts through the covering normal mucosa in rats.

CONCLUSIONS

Indocyanine green-labeled dasatinib could visualize GIST cells and xenografted tumors. The antitumor effect of ICG-dasatinib was preserved to the same degree as imatinib.

Comparison of therapeutic outcomes of sorafenib and lenvatinib as primary treatments for hepatocellular carcinoma with a focus on molecular-targeted agent sequential therapy: A propensity score-matched analysis

AIM

The optimal choice between sorafenib (SOR) or lenvatinib (LEN) as the first-line treatment for unresectable hepatocellular carcinoma (u-HCC) remains debatable. Using propensity score matching, this study compares the outcomes of SOR and LEN in the molecular-targeted agent (MTA) sequential treatment of u-HCC patients.

METHODS

This retrospective, multicenter, observational study recruited 137 u-HCC patients who underwent primary treatment with LEN (n = 52) or SOR (n = 85) between June 2017 and June 2020 after regorafenib was approved as the secondary treatment for u-HCC. Propensity score matching was used to reduce confounding, resulting in the selection of 104 patients (n = 52 for the SOR and LEN cohorts).

RESULTS

The median overall survival was 21.8 months for LEN and 20.4 months for SOR. LEN exhibited significantly greater therapeutic efficacy as compared to SOR (objective response rate: 3.8% [SOR] vs. 42.3% [LEN], p < 0.01; progression-free survival: 10 months [LEN] vs. 5.1 months [SOR], p < 0.01). No significant intergroup differences were noted in the rate of transition to secondary MTA treatments (SOR: 58.7%; LEN: 48.4%), adverse events (SOR: 86%; LEN: 95%), and maintenance of the Child-Pugh (CP) score during treatment. Compared to non-MTA treatments, secondary MTA treatment achieved a greater improvement in survival (4.3  vs. 2.8 months, p = 0.0047). Multivariate analysis demonstrated that the CP score (p < 0.01) and alpha-fetoprotein level (p < 0.01) were independent prognostic factors.

CONCLUSIONS

Both SOR and LEN treatments showed a clinically comparable therapeutic efficacy as the first-line treatments for u-HCC patients in an MTA sequential therapy.

Sorafenib as second-line treatment option after failure of lenvatinib in patients with unresectable hepatocellular carcinoma

Background and Aim

Currently, there is no molecular‐targeted agent that has demonstrated evidence of efficacy in patients with unresectable hepatocellular carcinoma (u‐HCC) who have developed resistance to treatment with lenvatinib (LEN). In this real‐world study, we aimed to investigate the therapeutic effect and safety of sorafenib (SOR) in patients with u‐HCC after progression on treatment with LEN.

Methods (Patients) and Results

A total of 13 patients with u‐HCC (12 males and 1 female), who were treated with SOR after progression on LEN, were enrolled in this retrospective study. Therapeutic efficacy was evaluated via contrast‐enhanced computerized tomography at 8 weeks after the initiation of SOR therapy according to modified response evaluation criteria in solid tumors (mRECIST) and RECIST. According to mRECIST, the objective response rate (ORR) and disease control rate (DCR) were 15.3% (2/13) and 69.2% (9/13), respectively. According to RECIST, the ORR and DCR were 0% (0/13) and 69.2% (9/13), respectively. The median progression‐free survival was 4.1 months. The median albumin‐bilirubin scores did not deteriorate significantly at 4, 6, and 8 weeks after initiation of SOR, compared with the scores at the baseline. The most frequent grade 1 or 2 adverse events (AEs) were palmar–plantar erythrodysesthesia, fatigue, diarrhea, and hypertension. There was no incidence of grade 3 AEs.

Conclusion

Treatment with SOR may be effective for u‐HCC after failure on LEN and may not worsen the liver reserve.

Clinical impact of primary tumour location, early tumour shrinkage, and depth of response in the treatment of metastatic colorectal cancer with first-line chemotherapy plus cetuximab or bevacizumab

The primary tumour location is an important prognostic factor for previously untreated metastatic colorectal cancer (mCRC). However, the predictive efficacies of primary tumour location, early tumour shrinkage (ETS), and depth of response (DpR) on mCRC treatment has not been fully evaluated. This study aimed to investigate the predictive efficacies of these traits in mCRC patients treated with first-line 5-fluorouracil-based chemotherapy plus biologic agents, namely, cetuximab and bevacizumab. This was a retrospective analysis of the medical records of 110 patients with pathology-documented unresectable mCRC. Patients with left-sided mCRC receiving any first-line regimen showed better overall survival (OS) than those with right-sided mCRC [33.3 vs 16.3 months; hazard ratio (HR) 0.44; 95% confidence interval (CI) 0.27–0.74; p < 0.001]. In patients with left-sided tumours, treatment with chemotherapy plus cetuximab yielded longer OS than chemotherapy plus bevacizumab (50.6 vs 27.8 months, HR 0.55; 95% CI 0.32–0.97; p = 0.0378). mCRC patients with ETS and high DpR showed better OS than those lacking ETS and with low DpR (33.5 vs 19.6 months, HR 0.50, 95% CI 0.32–0.79, p = 0.023 and 38.3 vs 19.0 months, HR 0.43, 95% CI 0.28–0.68, p < 0.001, respectively). Moreover, ETS and/or high DpR achieved in patients with right-sided mCRC receiving chemotherapy plus cetuximab were associated with significantly better OS than in those lacking ETS and with low DpR (34.3 vs 10.4 months, HR 0.19, 95% CI 0.04–0.94, p = 0.025 and 34.3 vs 10.4 months, HR 0.19, 95% CI 0.04–0.94, p = 0.0257, respectively). Taken together, our study demonstrates that primary tumour location is not only a well-known prognostic factor but also a relevant predictive factor in patients with mCRC receiving chemotherapy plus cetuximab. Additionally, both ETS and DpR could predict treatment outcomes and also potentially guide cetuximab treatment even in right-sided mCRCs.

Synergistic anti-tumor activity of miriplatin and radiation through PUMA-mediated apoptosis in hepatocellular carcinoma

BACKGROUND

The prognosis for patients with unresectable advanced hepatocellular carcinoma (HCC) is poor. Miriplatin is a hydrophobic platinum compound that has a long retention time in lesions after transarterial chemoembolization (TACE). We investigated anti-tumor activity of miriplatin combined with irradiation on HCC cells, and its underlying mechanism of apoptosis. We also analyzed the effectiveness of miriplatin-TACE and radiotherapy for locally advanced HCC.

METHODS

Human HCC cell lines HepG2 and HuH-7 were treated with DPC (active form of miriplatin) and radiation, and synergy was evaluated using a combination index (CI). Apoptosis-related proteins and cell cycles were analyzed by western blotting and flowcytometry. We retrospectively analyzed treatment outcomes in 10 unresectable HCC patients with vascular/bile duct invasion treated with miriplatin-TACE and radiotherapy.

RESULTS

DPC or X-ray irradiation decreased cell viability dose-dependently. DPC plus irradiation decreased cell viability synergistically in both cell lines (CI < 1, respectively). Cleaved PARP expression was induced much more strongly by DPC plus irradiation than by each treatment alone. Expression of p53 up-regulated modulator of apoptosis (PUMA) was significantly induced by the combination, and knockdown of PUMA with siRNA significantly decreased apoptosis in both cell lines. DPC plus irradiation caused sub-G1, G2/M, and S phase cell arrest in those cells. The combination of miriplatin-TACE and radiotherapy showed a high response rate for patients with locally advanced HCC despite small number of patients.

CONCLUSIONS

Miriplatin plus irradiation had synergistic anti-tumor activity on HCC cells through PUMA-mediated apoptosis and cell cycle arrest. This combination may possibly be effective in treating locally advanced HCC.

Conversion therapy for unresectable hepatocellular carcinoma after lenvatinib: Three case reports

INTRODUCTION

Lenvatinib (LEN) is a novel potent multi-tyrosine kinase inhibitor, approved as first-line treatment for unresectable hepatocellular carcinoma (HCC). Considering its high objective response rate, LEN therapy could be expected to achieve downstaging of tumors and lead to conversion therapy with hepatectomy or ablation. However, the feasibility of conversion therapy after LEN treatment in unresectable HCC remains largely unknown.

PATIENT CONCERNS

Here, we reported 3 cases of unresectable HCC: case 1, a 69-year-old man diagnosed with ruptured HCC; case 2, a 72-year-old woman with nonalcoholic steatohepatitis-based HCC; and case 3, a 73-year-old man with a history of alcoholic cirrhosis-based HCC.

DIAGNOSIS

In all cases, cirrhosis was classified as Child-Pugh 5 and modified albumin-bilirubin grade 1 or 2a. HCC was diagnosed as Barcelona Clinic Liver Cancer (BCLC) stage B.

INTERVENTIONS

In all cases, LEN was initiated after conventional-transcatheter arterial embolization enforcement, while maintaining liver function.

OUTCOMES

In all cases, the main tumor size decreased after 6 months of LEN treatment and no satellite nodes were detected, indicating downstaging of HCC to BCLC stage A. Subsequently, conversion hepatectomy or ablation was performed. After successful conversion therapy, the general condition of the patients was good, without tumor recurrence during the observation period (median 10 months).

LESSONS

This study demonstrated that LEN enables downstaging of HCC and thus represents a bridge to successful surgery or ablation therapy. In particular, LEN treatment may facilitate the possibility for conversion therapy of initially unresectable HCC, while maintaining the hepatic functional reserve.

Cancer-associated adipocytes promote pancreatic cancer progression through SAA1 expression

Although pancreatic cancer often invades peripancreatic adipose tissue, little information is known about cancer-adipocyte interaction. We first investigated the ability of adipocytes to de-differentiate to cancer-associated adipocytes (CAAs) by co-culturing with pancreatic cancer cells. We then examined the effects of CAA-conditioned medium (CAA-CM) on the malignant characteristics of cancer cells, the mechanism underlying those effects, and their clinical relevance in pancreatic cancer. When 3T3-L1 adipocytes were co-cultured with pancreatic cancer cells (PANC-1) using the Transwell system, adipocytes lost their lipid droplets and changed morphologically to fibroblast-like cells (CAA). Adipocyte-specific marker mRNA levels significantly decreased but those of fibroblast-specific markers appeared, characteristic findings of CAA, as revealed by real-time PCR. When PANC-1 cells were cultured with CAA-CM, significantly higher migration/invasion capability, chemoresistance, and epithelial-mesenchymal transition (EMT) properties were observed compared with control cells. To investigate the mechanism underlying these effects, we performed microarray analysis of PANC-1 cells cultured with CAA-CM and found a 78.5-fold higher expression of SAA1 compared with control cells. When the SAA1 gene in PANC-1 cells was knocked down with SAA1 siRNA, migration/invasion capability, chemoresistance, and EMT properties were significantly attenuated compared with control cells. Immunohistochemical analysis on human pancreatic cancer tissues revealed positive SAA1 expression in 46/61 (75.4%). Overall survival in the SAA1-positive group was significantly shorter than in the SAA1-negative group (P = .013). In conclusion, we demonstrated that pancreatic cancer cells induced de-differentiation in adipocytes toward CAA, and that CAA promoted malignant characteristics of pancreatic cancer via SAA1 expression, suggesting that SAA1 is a novel therapeutic target in pancreatic cancer.

Potential use of lenvatinib for patients with unresectable hepatocellular carcinoma including after treatment with sorafenib: Real-world evidence and in vitro assessment via protein phosphorylation array

The efficacy and safety of lenvatinib (LEN) as a second/third-line treatment for unresectable hepatocellular carcinoma (HCC) after sorafenib (SOR) therapy remains unknown. We evaluated the outcomes of second/third-line LEN treatment, investigated the sensitivity of a SOR-resistant HCC cell line (PLC/PRF5-R2) to LEN, and assessed their signal transduction pathways by protein array analysis. We retrospectively enrolled 57 patients with unresectable HCC. Fifty-three radiologically evaluated patients comprised 34 molecular-targeted agent (MTA)-naive (first-line), nine intolerant to SOR (second-line), and 10 resistant to regorafenib (third-line). The objective response rates (ORRs) were 61.8% in first-line, 33.3% in second-line, and 20.0% in third-line groups. The overall survival (OS) in the first-line was significantly longer than that in the third-line group (p < 0.05). Patients with better liver functional reserves (child score, ALBI grade) exhibited higher ORR and longer OS. The IC₅₀ of LEN against PLC/PRF5-R2 was significantly higher than that against PLC/PRF5. LEN significantly inhibited more LEN-related signal transduction pathways in PLC/PRF5 than in PLC/PRF5-R2 cells. This suggests that LEN is active and safe as a second/third-line treatment for unresectable HCC. LEN seems more effective for patients with HCC with better hepatic reserve functions or before MTA-resistance is acquired because of the partial cross-resistance to SOR.

JMJD2A sensitizes gastric cancer to chemotherapy by cooperating with CCDC8

BACKGROUND

Jumonji domain-containing protein 2A (JMJD2A) of the JMJD2 family of histone lysine demethylases has been implicated in tumorigenesis. However, its expression and role in gastric cancer (GC) drug resistance remain unknown. Here, we investigated the role of JMJD2A in GC chemotherapeutic susceptibility and its clinical relevance in GC.

METHODS

We selected 12 relevant genes from previously identified gene signatures that can predict GC susceptibility to docetaxel, cisplatin, and S-1 (DCS) therapy. Each gene was knocked down using siRNA in GC cell lines, and cell viability assays were performed. JMJD2A expression in GC cell lines and tissues was assessed using qRT-PCR and immunohistochemistry, respectively. A JMJD2A downstream target related to drug susceptibility was examined using whole-gene expression array and immunoprecipitation.

RESULTS

Among the 12 candidate genes, down-regulation of JMJD2A showed the maximum effect on GC susceptibility to anti-cancer drugs and increased the IC₅₀ values for 5-FU, cisplatin, and docetaxel 15.3-, 2.7-, and 4.0-fold, respectively. JMJD2A was universally expressed in 12 GC cell lines, and its overexpression in GC tissue was positively correlated with tumor regression in 34 DCS-treated patients. A whole-gene expression array of JMJD2A-knockdown GC cells demonstrated a significant decrease in the expression of pro-apoptotic coiled-coil domain containing 8 (CCDC8), a downstream target of JMJD2A. Direct interaction between CCDC8 and JMJD2A was verified using immunoprecipitation. CCDC8 inhibition restored drug resistance to docetaxel, cisplatin, and S-1.

CONCLUSIONS

Our results indicate that JMJD2A is a novel epigenetic factor affecting GC chemotherapeutic susceptibility, and JMJD2A/CCDC8 is a potential GC therapeutic target.

Potential use of lenvatinib for patients with unresectable hepatocellular carcinoma beyond progression of sorafenib treatment: A real-world evidence and in vitro assessment with protein phosphorylation array

485

Background: No information is available on the efficacy and safety of lenvatinib (LEN) as a second/third-line treatment for unresectable hepatocellular carcinoma (HCC) after sorafenib (SOR) therapy. We evaluated the characteristics and the therapeutic efficacy and safety of LEN as a second- and third-line treatment as well as first- treatment for unresectable HCC patients in clinical settings. Moreover, to rationalize these clinical findings in vitro, we assessed the anti-tumor activity of LEN on SOR-resistant cell line and performed a comprehensive phosphorylated protein array analysis associated with 377 signal transduction pathways using SOR-resistant and parental HCC cells. Methods: We retrospectively enrolled 51 unresectable HCC patients. Radiologic responses in 41 patients were evaluated by modified RECIST. Active signal transduction pathways in the cells were identified by protein array analysis, including 1205 proteins. Results: The evaluated patients comprised 25 TKI-naive (first- line), 7 intolerant to SOR (second-line), and 9 patients resistant to regorafenib (third-line). The ORRs were 64% in first-line, 42.8% in second-line, and 22.2% in third-line groups (first-line vs. third-line p< 0.05). The OS in the first-line was significantly longer than that in third-line group ( p< 0.05). Patients with better liver functional reserve (Child score, ALBI grade) exhibited higher ORR and longer OS. LEN was well-tolerated in the second/third-line treatment. The IC50 value of LEN against PLC/PRF5-R2 (30 μM) was significantly higher than that against PLC/PRF5 (6.4 μM). LEN significantly inhibited more signal transduction pathways related to FRS2, a crucial FGFR downstream molecule, in PLC/PRF5 than in PLC/PRF5-R2 cells. Conclusions: Our study indicates that LEN was active and safe in the second/third-line treatment for unresectable HCC. LEN seems more effective for HCC patients with better hepatic reserve function, or before TKI-resistance is acquired because of the partial cross-resistance to SOR.

Different phenotypes of gastric fundic gland polyposis and cancer in patients with familial adenomatous polyposis depending on Helicobacter pylori infection

A 37-year-old male with tarry stool presented to our hospital. Esophagogastroduodenoscopy revealed advanced gastric cancer, fundic gland polyposis (FGPsis), and negativity for Helicobacter pylori (HP) infection. Computed tomography exhibited multiple liver tumors. Total colonoscopy (TCS) demonstrated 139 tubular adenomas. He was diagnosed as having unresectable gastric cancer and received systemic chemotherapy. His sister and mother had colorectal adenomatous polyposis as revealed by TCS. His sister had FGPsis and was negative for HP infection, whereas his mother had early gastric cancer with HP infection but not FGPsis. Genetic analysis revealed a novel mutation in exon 15 of the APC gene (NM_000038.5: c.7647_7648_delTG) for the patient, his mother, and his sister, whereas no mutation was found for his father who had no gastrointestinal polyps. Therefore, the pedigree was diagnosed as an FAP family with a novel APC germline mutation which had different gastric phenotypes depending on the status of HP infection.

Epidermal growth factor receptor-targeted molecular imaging of colorectal tumors: Detection and treatment evaluation of tumors in animal models

To overcome the problem of overlooking colorectal tumors, a new and highly sensitive modality of colonoscopy is needed. Moreover, it is also important to establish a new modality to evaluate viable tumor volume in primary lesions of colorectal cancer (CRC) during chemotherapy. Therefore, we carried out molecular imaging of colorectal tumors targeting epidermal growth factor receptor (EGFR), which is highly expressed on tumor cells, for evaluating chemotherapeutic efficacy and for endoscopic detection of colorectal adenomas. We first attempted to image five CRC cell lines with various levels of EGFR expression using an Alexa Fluor-labeled anti-EGFR monoclonal antibody (AF-EGFR-Ab). A strong fluorescence signal was observed in the cells depending on the level of EGFR expression. When nude mice xenografted with LIM1215 CRC cells, which highly express EGFR, were i.v. injected with AF-EGFR-Ab, a strong fluorescence signal appeared in the tumor with a high signal to noise ratio, peaking at 48 hours after injection and then gradually decreasing, as shown using an IVIS Spectrum system. When the xenografted mice were treated with 5-fluorouracil, fluorescence intensity in the tumor decreased in proportion to the viable tumor cell volume. Moreover, when the colorectum of azoxymethane-treated rats was observed using a thin fluorescent endoscope with AF-EGFR-Ab, all 10 small colorectal adenomas (≤3 mm) were detected with a clear fluorescence signal. These preliminary results of animal experiments suggest that EGFR-targeted fluorescent molecular imaging may be useful for quantitatively evaluating cell viability in CRC during chemotherapy, and also for detecting small adenomas using a fluorescent endoscope.

A dose-escalation study of docetaxel, oxaliplatin, and S-1 (DOS) as a first-line therapy for patients with unresectable metastatic gastric cancer

PURPOSE

The aim of this study was to determine the recommended dose (RD) for a docetaxel/oxaliplatin/S-1 (DOS) regimen in patients with unresectable gastric cancer and to preliminarily evaluate its efficacy.

METHODS

Previously untreated patients with histologically proven unresectable metastatic gastric cancer were enrolled (n = 16). Docetaxel and oxaliplatin were administered intravenously on day 8 and S-1 was administered orally twice a day on days 1-14. Each cycle was repeated every 3 weeks. Dose-limiting toxicities (DLTs) were evaluated during the first treatment cycle. Three dose escalations of DOS were employed in this study: level 1 (50/100/80 mg/m²), level 2 (50/130/80 mg/m²), and level 3 (60/130/80 mg/m²).

RESULTS

According to the 3 + 3 dose-escalating schedule, we determined that the RD and maximum tolerated dose for this regimen were level 1 and level 2, respectively. The DLTs were grade 3 diarrhea and febrile neutropenia. The overall response rate was 78% (7/9) for patients with measurable lesions and consisted of two complete responses and five partial responses. Five patients underwent conversion surgery. The median follow-up time was 19 months with median survival time and progression-free survival being 19.6 months and 7.6 months, respectively.

CONCLUSIONS

The results from this study demonstrated the safety and tolerability of DOS in unresectable metastatic gastric cancer patients and revealed promising preliminary efficacy with a high conversion rate. A phase II trial of DOS regimen using the identified RD is ongoing.

Detection of aberrant crypt foci with image-enhanced endoscopy

Background and study aims  Conventional detection of aberrant crypt foci (ACF) with dye-spraying and magnifying observation is labor- and skill-intensive. We performed a prospective non-inferiority study to investigate the utility of image-enhanced endoscopy (IEE) for detection of ACF. Patients and methods  Patients with a history of colorectal neoplasm were eligible. The number of ACF in the lower rectum was counted first using IEE magnification with narrow-band imaging (NBI) or blue-laser imaging (BLI), and subsequently using the methylene blue method. The primary endpoint was the ACF detection rate with IEE, i. e., the number of ACF detected with IEE relative to the number of ACF detected with methylene blue. The secondary endpoints were bowel preparation time, ACF detection time, and the detection rate with NBI or BLI. Results  A total of 40 patients were enrolled (NBI 20 and BLI 20). The overall detection rate for ACF with IEE was 81.7 % (503/616; 95 %CI 78.8 - 84.6 %), meeting the primary endpoint. The detection rate for ACF with BLI (84.9 %, 258/304) was significantly higher than with NBI (78.5 %, 245/312; P  < 0.05). Both bowel preparation time and ACF detection time were significantly shorter with IEE versus the methylene blue method ( P  < 0.01, respectively). The detection rates for dysplastic and non-dysplastic ACF with IEE were 84.4 % (27/32) and 80.3 % (469/584), respectively. Conclusion  IEE is able to detect ACF during colonoscopy with sensitivity non-inferior to that of the conventional methylene blue method. IEE is simpler than the methylene blue method and is therefore a potentially useful new tool for ACF detection.

Massive hemobilia following plastic stent removal in common bile duct cancer associated with primary sclerosing cholangitis (with video)

Hemobilia is defined as bleeding into the biliary tract. Herein, we report a very rare case of massive hemobilia following plastic stent (PS) removal in common bile duct (CBD) cancer. A 72-year-old man with primary sclerosing cholangitis had undergone repeated insertion of a PS into the CBD. Biliary tract biopsy was performed based on suspicion of combined CBD cancer. Biopsy revealed poorly differentiated adenocarcinoma of the CBD. One month after the biliary tract biopsy, he was admitted for acute cholangitis, and endoscopic retrograde cholangiography was performed for the exchange of the PS. When one of the two biliary PSs was removed, spurting bleeding from the major papilla began abruptly. The massive bleeding caused the patient to be in a pre-shock state. A retrieval balloon catheter was compressed against the papilla for hemostasis. Although he was treated conservatively, the patient developed a bloody discharge. Upper gastrointestinal endoscopy revealed that the pulsatile bleeding beside the PSs started immediately after the removal of the coagula. Emergent contrast-enhanced computed tomography showed right hepatic artery aneurysm across the CBD. Therefore, transarterial embolization was performed. The patient's post-therapeutic course was uneventful. He received chemotherapy, but died about a half year after hemobilia occurred.

A Novel Theranostic Combination of Near-infrared Fluorescence Imaging and Laser Irradiation Targeting c-KIT for Gastrointestinal Stromal Tumors

It is difficult to distinguish gastrointestinal stromal tumors (GISTs) from other types of submucosal tumors under conventional gastrointestinal endoscopy. We aimed to detect GISTs by molecular fluorescence imaging using a near-infrared (NIR) photosensitizer (IR700)-conjugated anti-c-KIT antibody and to treat GISTs by photoimmunotherapy with NIR irradiation as a non-invasive theranostic procedure. We also investigated the therapeutic mechanisms. Methods: Human GIST cell lines GIST-T1 and GIST-882M were incubated with IR700-conjugated anti-c-KIT antibody, IR700-12A8, and observed by confocal laser microscopy. Mice with GIST-T1 xenografts or rats with orthotopic xenografts were injected with IR700-12A8 or AF488-conjugated antibody, and observed under IVIS or autofluorescence imaging (AFI) endoscopy. GIST cells were treated with IR700-12A8 and NIR light in vitro and vivo, and cell viability, histology and apoptosis were evaluated. Results: Strong red fluorescence of IR700-12A8 was observed on the cell membrane of GIST cells and was gradually internalized into the cytoplasm. Tumor-specific accumulation of IR700-12A8 was observed in GIST-T1 xenografts in mice. Under AFI endoscopy, a strong fluorescence signal was observed in orthotopic GIST xenografts in rats through the normal mucosa covering the tumor. The percentage of dead cells significantly increased in a light-dose-dependent manner and both acute necrotic and late apoptotic cell death was observed with annexin/PI staining. Cleaved PARP expression was significantly increased after IR700-12A8-mediated NIR irradiation, which was almost completely reversed by NaN₃. All xenograft tumors (7/7) immediately regressed and 4/7 tumors completely disappeared after IR700-12A8-mediated NIR irradiation. Histologic assessment and TUNEL staining revealed apoptosis in the tumors. Conclusion: NIR fluorescence imaging using IR700-12A8 and subsequent NIR irradiation could be a very effective theranostic technology for GIST, the underlying mechanism of which appears to involve acute necrosis and supposedly late apoptosis induced by singlet oxygen.

Linked color imaging enhances endoscopic detection of sessile serrated adenoma/polyps

BACKGROUND AND STUDY AIMS

 Although new image-enhanced endoscopy (IEE) technologies such as blue laser imaging (BLI), BLI-bright, and linked color imaging (LCI) have been developed, their utility for the detection of sessile serrated adenoma/polyps (SSA/Ps) is still unclear. This study aimed to evaluate the utility of BLI, BLI-bright, and LCI for SSA/P detection in still image examinations and in a prospective randomized controlled trial (RCT).

PATIENTS AND METHODS

 A group of 6 expert and non-expert endoscopists read 200 endoscopic still images containing SSA/P lesions using white light image (WLI), BLI, BLI-bright, and LCI. Color differences were calculated using the color space method. A prospective RCT of tandem colonoscopy with WLI and LCI was performed. Patients with SSA/P and those with a history of SSA/P that had been endoscopically removed were enrolled and randomly allocated to WLI-LCI or LCI-WLI groups. Additional endoscopic detection rates for SSA/P were compared between the 2 groups.

RESULTS

 LCI showed the highest SSA/P detection rate among the 4 modes for both expert and non-expert endoscopists. The detection rate with LCI for the 6 expert endoscopists (mean 98.3 ± standard deviation 2.0 %) was significantly higher than that with WLI (86.7 ± 6.0 %, P  < 0.01). Likewise, the detection rate with LCI for the 6 non-expert endoscopists (92.3 ± 2.9 %) was significantly higher than that with WLI (72.7 ± 11.5 %, P  < 0.01). The color difference of SSA/P with LCI was the highest among the 4 modes, and was significantly higher than with WLI (median 15.9, (interquartile range 13.7 - 20.6) vs. 10.2, (7.6 - 14.2); P  < 0.0001). In the RCT, a total of 44 patients (WLI-LCI 22 vs. LCI-WLI 22) underwent colonoscopy. The additional detection rate for SSA/P in the second inspection in the WLI-LCI group (21.6 %, 8/37) was significantly higher than in the LCI-WLI group (3.2 %, 1/31; P  = 0.02). The small, flat, non-mucus and isochromatic SSA/Ps in the transverse colon were detected more frequently in the second inspection with LCI.

CONCLUSIONS

 LCI was the most sensitive mode for SSA/P detection among WLI, BLI, BLI-bright, and LCI in the still image examinations. Our RCT strongly suggests that LCI is superior to conventional WLI for SSA/P detection during colonoscopy. UMIN000017599.

Poly-(ADP-Ribose) Polymerase-1 Promotes Prothrombin Gene Transcription and Produces Des-Gamma-Carboxy Prothrombin in Hepatocellular Carcinoma

BACKGROUND AND AIM

Although des-gamma-carboxy prothrombin (DCP) is a well-known tumor marker for hepatocellular carcinoma (HCC), the mechanism of DCP production is unclear. This study aimed to investigate the mechanism how DCP is produced in HCC cells.

METHODS

Levels of mRNA and DCP were analyzed by real-time polymerase chain reaction and electro-chemiluminescence immunoassay respectively. Secreted alkaline phosphatase (SEAP) expression vectors including deletion mutants of the prothrombin gene promoter were constructed for reporter gene assay. The transcription factors bound to DNA fragments were analyzed by mass spectrometry. An electrophoretic mobility shift assay (EMSA) was performed using a biotin end-labeled DNA.

RESULTS

The prothrombin mRNA levels in all 5 DCP producing cell lines were appreciably high. However, those in 2 DCP non-producing cell lines were below detectable levels. A SEAP vector with -2985 to +27 showed a very high transcription activity in DCP-producing Huh-1 cells. However, transcription abruptly decreased when the vector with -2955 to +27 was transfected, and then remained at the similar levels with larger deletion mutants, indicating the existence of a cis-element at -2985 to -2955 (31-bp). Mass spectrometry analysis identified the protein that bound to the 31-bp DNA as poly-(ADP-ribose) polymerase-1 (PARP-1). Knockdown of the PARP-1 gene by small interfering RNA in Huh-1 cells induced marked inhibition of prothrombin gene transcription. The EMSA clearly showed that PARP-1 specifically binds to the 31-bp DNA fragment in the prothrombin gene promoter.

CONCLUSIONS

Our data suggest that PARP-1 activates prothrombin gene transcription and that the excessive prothrombin gene transcription induces DCP production in DCP-producing HCC cells.

A dose-escalation study of docetaxel, oxaliplatin and S-1 (DOS) as a first-line therapy for patients with unresectable metastatic gastric cancer

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Background: Although the triplet regimen of docetaxel/cisplatin/S-1 (DCS) has shown promising activity and conversion rate in patients with unresectable metastatic gastric cancer (UMGC) in Japan, it was accompanied by severe adverse events. Recent studies suggested that oxaliplatin was almost as active, and relatively less toxic, than cisplatin in combination regimens for UMGC and can therefore replace cisplatin. The aim of this study was to determine the maximum tolerated dose (MTD), dose-limiting toxicities (DLTs), recommended dose (RD), and preliminary efficacy of docetaxel/oxaliplatin/S-1 (DOS) instead of DCS in patients with UMGC. Methods: Previously untreated 16 patients with histologically proven UMGC were enrolled. Docetaxel and oxaliplatin were administered intravenously on day 8. S-1 was administered orally twice a day on days 1-14. Each cycle was repeated every 3 weeks. DLTs were evaluated during the first cycle of treatment. Three dose-escalations of DOS were used in this study namely, level 1 (50/100/80 mg/m2), level 2 (50/130/80 mg/m2), and level 3 (60/130/80 mg/m2). Results: Among the six patients, one patient each experienced DLTs (febrile neutropenia and diarrhea) at level 1 and 2 doses, respectively. While two more patients experienced DLTs (febrile neutropenia and diarrhea) after administration of level 3 doses. Therefore, two additional patients were enrolled into the study at level 2. However, both these patients subsequently exhibited DLTs (febrile neutropenia and diarrhea). Therefore, we concluded that the MTD and RD with this regimen were level 2 and level 1, respectively, and that the DLT were grade 3 diarrhea and febrile neutropenia. The overall response rate was 78% (7/9) of the patients with measurable lesions, consisting of two complete response and five partial responses. Five patients underwent conversion surgery. Conclusions: The RD of the 3-weekly DOS regimen in patients with UMGC was docetaxel at 50 mg/m2 and oxaliplatin at 100 mg/m2 on day 8 and S-1 at 80 mg/m2 on days 1-14. The efficacy and ease of administration make the regimen a promising alternative to DCS. A phase II study using this RD regimen is currently underway. Clinical trial information: 000015849.

APOB codon 4311 polymorphism is associated with hepatitis C virus infection through altered lipid metabolism

Background

It has been reported that some single-nucleotide polymorphisms (SNPs) in lipid regulators such as apolipoproteins and cell surface molecules for hepatitis C virus (HCV) entry into hepatocytes are associated with HCV infection. However, it is unknown how HCV infection is affected by altered lipid metabolism resulting from the SNPs. We investigated the relationship between these SNPs and HCV infection status, and also analyzed the mechanism by which these SNPs mediate HCV infection via lipid metabolism alterations.

Methods

Serum lipid and apolipoprotein profiles were tested in 158 HCV-positive and 220 HCV-negative subjects. We selected 22 SNPs in five lipid regulator genes which were related to HCV entry into hepatocytes and to lipid metabolism (APOA1, APOB, SR-B1, LDLR, and APOE), and their polymorphisms were analyzed using the PCR-sequence-specific oligonucleotide probe-Luminex method.

Results

An APOB N4311S (g.41553a > g) SNP, rs1042034, was significantly associated with HCV positivity; the HCV positivity rate for the minor allele AA genotype was significantly higher than for genotype AG + GG (P = 0.016). Other SNPs except for APOB P2712L SNP rs676210, which is in linkage disequilibrium with rs1042034, showed no significant difference in genotype distribution. The serum level of low density lipoprotein-cholesterol (LDL-C) in the genotype AA group was significantly lower than in the genotype non-AA group (P = 0.032), whereas the triglyceride (TG) level was significantly higher (P = 0.007).

Conclusion

An APOB SNP, rs1042034, is closely associated with HCV infection through lipid metabolism alteration. The minor allele AA genotype might contribute to facilitating serum LDL uptake into hepatocytes via LDLR by modifying their affinity and interaction and may have an influence on HCV infection by their entry to the liver through the LDLR.

Clinicopathological Assessment of Gastric Xanthoma as Potential Predictive Marker of Gastric Cancer

BACKGROUND/AIMS

Gastric xanthomas are frequently observed in the stomach as small yellowish plaques or nodules. A close relationship among Helicobacter pylori infection, atrophic gastritis, and xanthomas has been reported. We assessed the clinicopathological features of gastric cancer with or without xanthomas.

METHODS

A total of 91 patients who were diagnosed as having early gastric cancer were enrolled. We evaluated the gastritis status using scores for gastritis and atrophy, positivity of H. pylori infection, the prevalence rate of xanthomas, and the clinicopathological features of gastric cancer.

RESULTS

Gastric xanthomas were observed in 72.5% of early gastric cancer cases. Scores for gastritis and atrophy were significantly higher in the xanthoma-positive group than those in the xanthoma-negative group. A higher prevalence of differentiated-type adenocarcinoma was found in the xanthoma-positive group. Among the cases with multiple gastric xanthomas, the prevalence of males was significantly higher than that of females.

CONCLUSION

A high prevalence rate of gastric xanthomas in gastric cancer cases was shown. Xanthomas were highly associated with age, the severities of gastritis and atrophy, and differentiated-type adenocarcinoma. Regardless of the eradication of H. pylori, xanthomas may be useful predictive markers for the development of differentiated-type adenocarcinoma.

A triplet combination with capecitabine/oxaliplatin/irinotecan (XELOXIRI) plus cetuximab as first-line therapy for patients with metastatic colorectal cancer: a dose escalation study

PURPOSE

The addition of cetuximab to triplet chemotherapy can increase treatment efficacy for patients with metastatic colorectal cancer (mCRC). We explored the dose-limiting toxicity and feasibility of a triweekly capecitabine, oxaliplatin, irinotecan, plus cetuximab (XELOXIRI plus cetuximab) regimen in patients with wild-type KRAS mCRC.

METHODS

Patients received oxaliplatin (100 mg/m², day 1), capecitabine (1700 mg/m² per day from day 2 to 15), irinotecan (100, 120, and 150 mg/m² for dose levels 1, 2, 3, respectively, on day 1), and cetuximab (400 mg/m², day 1 and, thereafter, 250 mg/m² every week), repeated every 3 weeks. Dose-limiting toxicities (DLTs) were assessed in the first 2 treatment cycles to determine the maximum tolerated dose (MTD) and the recommended dose (RD).

RESULTS

Twelve patients received a median of 7 cycles of therapy (range 2-10). The DLT was grade 4 neutropenia, observed in 1 of 6 patients at dose level 2. The MTD was not reached at dose level 3. Therefore, the RD of irinotecan was defined as 150 mg/m². Most common grade ≥ 3 toxicities were neutropenia (50%), diarrhea (17%), and febrile neutropenia (8%). The response rate was 83% (complete and partial response: 1 and 9 patient(s), respectively), including 4 conversion cases.

CONCLUSIONS

The combination of XELOXIRI and cetuximab is feasible and has an acceptable toxicity profile; neutropenia was the DLT. The RD of irinotecan is 150 mg/m². The observed response rate was promising and warrants further investigation.

EGFR Downregulation after Anti-EGFR Therapy Predicts the Antitumor Effect in Colorectal Cancer

Anti-EGFR mAb is reported to induce EGFR internalization in colorectal cancer cells. However, the biological relevance of EGFR internalization with anti-EGFR mAb is unknown. Therefore, the relevance of EGFR downregulation with anti-EGFR mAb to antitumor activity in colorectal cancer cells was investigated. Quantification of EGFR on the cell surface before cetuximab treatment was assessed by flow cytometry, and its growth-inhibitory effects were measured by Trypan blue exclusion, in 10 RAS, BRAF wild-type colorectal cancer cell lines, but there was no significant correlation between EGFR number and its growth-inhibitory effect. However, a significant correlation existed between the percentage decrease in the number of EGFRs after cetuximab treatment and its growth-inhibitory effect in those cell lines. Treatment with TGFα, a ligand for EGFR, induced EGFR internalization in colorectal cancer cells, but most EGFRs subsequently recycled to the cell surface, consistent with previous studies. While cetuximab treatment induced EGFR internalization, most receptors subsequently translocated into the late endosome, leading to lysosomal degradation, as revealed by immunoblotting and double immunofluorescence. Cetuximab-sensitive colorectal cancer cells showed greater EGFR internalization, stronger cell growth inhibition, and more augmented apoptotic signals than nonsensitive cells. IHC for EGFR, performed using an EGFR pharmDx Kit (mouse anti-human EGFR mAb clone 2-18C9), in clinical specimens before and after anti-EGFR mAb therapy in 13 colorectal cancer patients showed a significant correlation between the response to anti-EGFR mAb and decreased staining after therapy.Implications: This report clearly demonstrates that anti-EGFR mAb facilitates internalization and subsequent degradation of EGFRs in lysosomes, which is an important determinant of the efficacy of anti-EGFR mAb treatment for colorectal cancer. Mol Cancer Res; 15(10); 1445-54. ©2017 AACR.

The differing influence of several factors on the development of fatty liver with elevation of liver enzymes between genders with metabolic syndrome: A cross-sectional study

Background

Nonalcoholic fatty liver disease (NAFLD) is known to be strongly associated with obesity, visceral fat, metabolic syndrome (MS), lifestyle, and lifestyle-related diseases in both males and females. However, the prevalence of NAFLD, MS, and clinical backgrounds is different between males and females.

Objective

We conducted a cross-sectional study to examine the differing influence of lifestyle-related factors and visceral fat on fatty liver (FL) with elevation of liver enzymes between males and females with MS.

Methods

We enrolled 42,134 persons who underwent a regular health check-up, and after excluding subjects who fulfilled excluding criteria, the remaining subjects were 2,110 persons with MS. We examined the differing influence of lifestyle-related factors and visceral fat on FL with elevation of alanine aminotransferase (ALT) (ALT elevation was defined as ALT level of ≥31 IU/l in the present study).

Results

The odds rations for FL with ALT elevation were as follows: WC, 1.83 (95% confidence interval (CI) 1.36–2.46); dyslipidemia, 1.89 (95% CI 1.34–2.68); hemoglobin A1c, 1.36 (95% CI 1.00–1.85); visceral fat type MS (V-type MS), 5.78 (95% CI 4.29–7.80); and light drinker, 0.56 (95% CI 0.41–0.78) in males with MS and BMI, 2.18 (95% CI 1.43–3.33); WC, 1.85 (95% CI 1.27–2.70); diastolic blood pressure, 1.69 (95% CI 1.16–2.45); triglyceride, 2.22 (95% CI 1.56–3.17); impaired glucose tolerance, 1.66 (95% CI 1.11–2.47); and V-type MS, 3.83 (95% CI 2.57–5.70) in females with MS. The prevalence of FL with ALT elevation and ALT was significantly higher in V-type MS than in the subcutaneous fat type MS in both males and females with MS (P < 0.001).

Conclusion

Although V-type MS and WC is a common significant predictor of an increased prevalence of FL with ALT elevation in both males and females with MS, gender, lifestyle-related factors, and MS type in individuals with MS should be considered for the development of FL with ALT elevation.

Plasma brain natriuretic peptide levels are elevated in patients with cancer

BACKGROUND

Natriuretic peptides have been proposed as biomarkers of cardiovascular disease, especially heart failure. Brain natriuretic peptide (BNP) has also been shown to be upregulated at the transcriptional and translational levels by pro-inflammatory cytokines in cardiac myocytes. Although we often measure plasma BNP levels in cancer patients, it remains unknown whether cancer-related inflammation affects the plasma BNP levels. We investigated the relationship between the BNP and human cancers.

METHODS

We retrospectively studied 2,923 patients in whom the plasma BNP levels and serum C-reactive protein (CRP) were measured and echocardiography was performed. Patients with clinically evident heart failure (NYHA II or higher), heart disease requiring medical treatment or surgery, renal dysfunction, and inflammatory disease were excluded. There were 234 patients in the final analysis. Blood sampling was performed before surgery and chemotherapy. In addition, we evaluated the relationship between the inflammation and plasma BNP levels in mouse models of colon cancer.

RESULTS

Of the 234 patients, 80 were diagnosed with cancer. Both the plasma BNP and serum CRP levels were significantly higher in cancer patients than those without. There were no significant differences in the echocardiographic parameters. There was a significant positive correlation between the plasma BNP and serum CRP levels in cancer patients (r = 0.360, P<0.01) but not in those without. In cancer patients, only the CRP correlated with the BNP independent of the age, creatinine level, hypertension, and body mass index. In addition, in nude mice with subcutaneous colon cancer, the plasma BNP level was elevated compared with that in non-cancer mice, and there was a significant relationship between the plasma BNP and serum levels of the inflammatory markers.

CONCLUSIONS

In cancer patients, as well as colon cancer model mice, the plasma BNP levels were elevated, possibly due to cancer-related inflammation. The effect of cancer on the BNP levels should be considered when using BNP as an indicator of heart failure in cancer patients.

Response Predictors of S-1, Cisplatin, and Docetaxel Combination Chemotherapy for Metastatic Gastric Cancer: Microarray Analysis of Whole Human Genes

OBJECTIVES

The aim of this study was to identify biomarkers for predicting the efficacy of docetaxel, cisplatin, and S-1 (DCS) therapy for advanced gastric cancer using microarrays of biopsy specimens before chemotherapy.

METHODS

Nineteen samples were taken from 19 patients with unresectable metastatic gastric cancer who received DCS as a first-line therapy. Laser capture microdissection was performed, and total cellular RNA was extracted from each microdissected sample. Whole-gene expression was analyzed by microarray, and the difference in mRNA expression observed with the microarrays was confirmed by quantitative real-time PCR. Immunohistochemical staining was performed using clinical tissue sections obtained by endoscopic biopsy.

RESULTS

Eleven patients were identified as early responders and 8 patients as nonresponders to DCS therapy. Twenty-nine genes showed significant differences in relative expression ratios between tumor and normal tissues. A classifier set of 29 genes had high accuracy (94.7%) for distinguishing gene expression between 11 early responders and 8 nonresponders. Decreasing the size of the classifier set to 4 genes (PDGFB, PCGF3, CISH, and ANXA5) increased the accuracy to 100%. Expression levels by real-time PCR for validation were well correlated with those 4 genes in microarrays.

CONCLUSION

The genes identified may serve as efficient biomarkers for personalized cancer-targeted therapy.

Downregulation of microRNA-100/microRNA-125b is associated with lymph node metastasis in early colorectal cancer with submucosal invasion

A majority of early colorectal cancers (CRCs) with submucosal invasion undergo surgical operation, despite a very low incidence of lymph node metastasis. Our study aimed to identify microRNAs (miRNAs) specifically responsible for lymph node metastasis in submucosal CRCs. MicroRNA microarray analysis revealed that miR‐100 and miR‐125b expression levels were significantly lower in CRC tissues with lymph node metastases than in those without metastases. These results were validated by quantitative real‐time PCR in a larger set of clinical samples. The transfection of a miR‐100 or miR‐125b inhibitor into colon cancer HCT116 cells significantly increased cell invasion, migration, and MMP activity. Conversely, overexpression of miR‐100 or miR‐125b mimics significantly attenuated all these activities but did not affect cell growth. To identify target mRNAs, we undertook a gene expression array analysis of miR‐100‐silenced HCT116 cells as well as negative control cells. The Ingenuity Pathway Analysis, TargetScan software analyses, and subsequent verification of mRNA expression by real‐time PCR identified mammalian target of rapamycin (mTOR) and insulin‐like growth factor 1 receptor (IGF1R) as direct, and Fas and X‐linked inhibitor‐of‐apoptosis protein (XIAP) as indirect candidate targets for miR‐100 involved in lymph node metastasis. Knockdown of each gene by siRNA significantly reduced the invasiveness of HCT116 cells. These data clearly show that downregulation of miR‐100 and miR‐125b is closely associated with lymph node metastasis in submucosal CRC through enhancement of invasion, motility, and MMP activity. In particular, miR‐100 may promote metastasis by upregulating mTOR, IGF1R, Fas, and XIAP as targets. Thus, miR‐100 and miR‐125b may be novel biomarkers for lymph node metastasis of early CRCs with submucosal invasion.

Efficacy of hybrid endoscopic submucosal dissection (ESD) as a rescue treatment in difficult colorectal ESD cases

BACKGROUND AND AIM

Endoscopic submucosal dissection (ESD), which provides a higher en bloc resection rate than conventional endoscopic mucosal resection (EMR), is considered to be a useful treatment option for large colorectal tumors. However, colorectal ESD is not widely used because of its technical difficulty, risk of complications and time required. To overcome these drawbacks, a simpler modified technique, ESD with snaring (hybrid ESD), has been developed. The aim of the present study was to retrospectively compare the safety and efficacy of hybrid ESD and conventional ESD for colorectal tumors.

METHODS

Between September 2008 and June 2016, ESD was carried out on 137 lesions and hybrid ESD on 27 lesions. All hybrid ESD cases were carried out as a rescue treatment in difficult ESD cases. We retrospectively investigated procedure time, and the rates of en bloc resection, perforation, bleeding, and local recurrence.

RESULTS

In the hybrid ESD group, procedure time was shorter compared with the ESD group (108 ± 59.5 min vs 122 ± 72.2 min), but the en bloc resection rate was lower (66.7% vs 94.2%). However, there were no significant differences in procedure time, or in rates of en bloc resection, perforation and bleeding between the two groups. Local recurrence did not develop in any of our cases.

CONCLUSIONS

Hybrid ESD as a rescue treatment in difficult ESD cases may be less effective for en bloc resection of large colorectal tumors. Indication for hybrid ESD may be limited to scheduled treatment from the outset and emergency cases with patients who present unstable vital signs during ESD.