Cancer stem cells in Epstein‐Barr virus‐associated gastric carcinoma

Cancer stem cells (CSCs) play a decisive role in the development and progression of cancer. To investigate CSCs in Epstein‐Barr virus (EBV)‐associated carcinoma (EBVaGC), we screened previously reported stem cell markers of gastric cancer in EBV‐infected gastric cancer cell lines (TMK1 and NUGC3) and identified CD44v6v9 double positive cells as candidate CSCs. CD44v6/v9^+/+ cells were sorted from EBVaGC cell line (SNU719) cells and EBV‐infected TMK1 cells and these cell populations showed high spheroid‐forming ability and tumor formation in SCID mice compared with the respective CD44v6/v9^?/? cells. Sphere‐forming ability was dependent on the nuclear factor‐κB (NF‐κB) signaling pathway, which was confirmed by decrease of sphere formation ability under BAY 11‐7082. Small interfering RNA knockdown of latent membrane protein 2A (LMP2A), one of the latent gene products of EBV infection, decreased spheroid formation in SNU719 cells. Transfection of the LMP2A gene increased the sphere‐forming ability of TMK1 cells, which was mediated through NF‐κB signaling. Together, these results indicate that CD44v6v9^+/+ cells are CSCs in EBVaGC that are maintained through the LMP2A/NF‐κB pathway. Future studies should investigate CD44v6/v9^+/+ cells in normal and neoplastic gastric epithelium to prevent and treat this specific subtype of gastric cancer infected with EBV.     

Neighborhood effect and obesity in adult survivors of pediatric cancer: A report from the St. Jude lifetime cohort study

Survivors of childhood cancer are at risk for obesity, a condition potentially modifiable if dietary intake and physical activity are optimized. These health behaviors are likely influenced by neighborhood of residence, a determinant of access to healthy, affordable food and safe and easy exercise opportunities. We examined associations between neighborhood level factors and obesity among survivors in the St. Jude Lifetime cohort and community comparison group members. Persons with residential addresses available for geocoding were eligible for analysis (n = 2,265, mean age 32.5 [SD 9.1] years, 46% female, 85% white). Survivors completed questionnaires regarding individual behaviors; percent body fat was assessed via dual X-ray absorptiometry (obesity: ≥25% males; ≥35% females); neighborhood effect was characterized using census tract of residence (e.g., neighborhood socioeconomic status [SES], rurality). Structural equation modeling was used to determine associations between neighborhood effect, physical activity, diet, smoking, treatment exposures and obesity. Obese survivors (n = 1,420, 62.7%) were more likely to live in neighborhoods with lower SES (RR: 1.23, 95% CI: 1.10–1.38) and rural areas (RR: 1.22, 95% CI: 1.07–1.39) compared to survivors with normal percent body fat. Resource-poor neighborhoods (standardized effect: 0.06, p < 0.001) and cranial radiation (0.16, p < 0.001) had direct effects on percent body fat. Associations between neighborhood of residence and percent body fat were increased (0.01, p = 0.04) among individuals with a poor diet. Neighborhoods where survivors reside as an adult is associated with obesity. Interventions targeting survivors should incorporate strategies that address environmental influences on obesity.     

Evaluating the Auto-MODS Assay,a Novel Tool for Tuberculosis Diagnosis for Use in Resource-Limited Settings

There is an urgent need for simple, rapid, and affordable diagnostic tests for tuberculosis (TB) to combat the great burden of the disease in developing countries. The microscopic observation drug susceptibility assay (MODS) is a promising tool to fill this need, but it is not widely used due to concerns regarding its biosafety and efficiency. This study evaluated the automated MODS (Auto-MODS), which operates on principles similar to those of MODS but with several key modifications, making it an appealing alternative to MODS in resource-limited settings. In the operational setting of Chiang Rai, Thailand, we compared the performance of Auto-MODS with the gold standard liquid culture method in Thailand, mycobacterial growth indicator tube (MGIT) 960 plus the SD Bioline TB Ag MPT64 test, in terms of accuracy and efficiency in differentiating TB and non-TB samples as well as distinguishing TB and multidrug-resistant (MDR) TB samples. Sputum samples from clinically diagnosed TB and non-TB subjects across 17 hospitals in Chiang Rai were consecutively collected from May 2011 to September 2012. A total of 360 samples were available for evaluation, of which 221 (61.4%) were positive and 139 (38.6%) were negative for mycobacterial cultures according to MGIT 960. Of the 221 true-positive samples, Auto-MODS identified 212 as positive and 9 as negative (sensitivity, 95.9%; 95% confidence interval [CI], 92.4% to 98.1%). Of the 139 true-negative samples, Auto-MODS identified 135 as negative and 4 as positive (specificity, 97.1%; 95% CI, 92.8% to 99.2%). The median time to culture positivity was 10 days, with an interquartile range of 8 to 13 days for Auto-MODS. Auto-MODS is an effective and cost-sensitive alternative diagnostic tool for TB diagnosis in resource-limited settings.     

Non–clinical efficacy,safety and stable clinical cell processing of induced pluripotent stem cell‐derived anti–glypican‐3 chimeric antigen receptor‐expressing natural killer/innate lymphoid cells

The use of allogeneic, pluripotent stem‐cell‐derived immune cells for cancer immunotherapy has been the subject of recent clinical trials. In Japan, investigator‐initiated clinical trials will soon begin for ovarian cancer treatment using human leukocyte antigen (HLA)‐homozygous‐induced pluripotent stem cell (iPSC)‐derived anti–glypican‐3 (GPC3) chimeric antigen receptor (CAR)‐expressing natural killer/innate lymphoid cells (NK/ILC). Using pluripotent stem cells as the source for allogeneic immune cells facilitates stringent quality control of the final product, in terms of efficacy, safety and producibility. In this paper, we describe our methods for the stable, feeder‐free production of CAR‐expressing NK/ILC cells from CAR‐transduced iPSC with clinically relevant scale and materials. The average number of cells that could be differentiated from 1.8‐3.6 × 10⁶ iPSC within 7 weeks was 1.8‐4.0 × 10⁹. These cells showed stable CD45/CD7/CAR expression, effector functions of cytotoxicity and interferon gamma (IFN‐γ) production against GPC3‐expressing tumor cells. When the CAR‐NK/ILC cells were injected into a GPC3‐positive, ovarian‐tumor‐bearing, immunodeficient mouse model, we observed a significant therapeutic effect that prolonged the survival of the animals. When the cells were injected into immunodeficient mice during non–clinical safety tests, no acute systemic toxicity or tumorigenicity of the final product or residual iPSC was observed. In addition, our test results for the CAR‐NK/ILC cells generated with clinical manufacturing standards are encouraging, and these methods should accelerate the development of allogeneic pluripotent stem cell‐based immune cell cancer therapies.     

Fecoflowmetric Analysis of Anorectal Motor Function in Postoperative Anal-Preserving Surgery Patients With Low Rectal Cancer Comparison With the Wexner Score and Anorectal Manometry

The aim of this study was to elucidate whether fecoflowmetry (FFM) could evaluate more detailed evacuative function than anorectal manometry by comparing between FFM or anorectal manometric findings and the clinical questionnaires and the types of surgical procedure in the patients who received anal-preserving surgery. Fifty-three patients who underwent anal-preserving surgery for low rectal cancer were enrolled. The relationships between FFM or the manometric findings and the clinical questionnaires and the types of procedure of anal-preserving surgery were evaluated. There were significant differences between FFM markers and the clinical questionnaire and the types of the surgical procedure, whereas no significant relationship was observed between the manometric findings and the clinical questionnaire and the types of the surgical procedure. FFM might be feasible and useful for the objective assessment of evacuative function and may be superior to manometry for patients undergoing anal-preserving surgery.Key words: Anorectal manometry, Anal-preserving surgery, Fecoflowmetry, Incontinence, Rectal cancerSphincter preservation has been one of the key issues of rectal cancer surgery. Low anterior resection (LAR)¹ and internal and external sphincter resection (ISR and ESR) are anal-preserving surgeries.^2,3 The aim of these procedures is to restore the normal process of defecation, along with its function, and to improve the quality of life of patients by avoiding permanent colostomy. However, anal-preserving surgery is often associated with evacuative dysfunction and various degrees of incontinence.^4–7Most studies that have assessed the evacuation function have used clinical questionnaires, which are subjective and may vary according to the patient perception.⁷ There are many factors that can affect the evacuative function, such as the stool consistency, rectal capacity, anal sphincters, pelvic floor muscles, and intra-abdominal pressure. Although manometry with or without the clinical score has also commonly been used, fecoflowmetry (FFM) has been reported to be more accurate and useful for assessing the postoperative anorectal motor function.^8–13 FFM was first introduced by Shafik and is a dynamic method for examining the anorectal motor activity that simulates the natural act of defecation.¹⁴ Some studies have shown its usefulness in postoperative patients with anorectal disease,^8–11 but only a few studies have been performed to examine the evacuative function following anal-preserving surgery.^12,13 The aim of this study was to evaluate the evacuative function in the postoperative period following anal-preserving surgery in patients with low rectal cancer using FFM, and to compare the results with the Wexner score and anorectal manometry.¹⁵