Two-year carcinogenicity study of a novel plasticizer, bis(2-ethylhexyl) cyclohexane-1,4-dicarboxylate (Eco-DEHCH), by oral diet in Han Wistar rats.

Plasticizers are necessary for the usability of various products, including food contact materials. Exposure to plasticizers is most commonly made through the oral route. Several plasticizers have been reported to have adverse effects on humans and the environment. Thus, the present study aimed to determine the long-term toxicity and carcinogenicity of a novel plasticizer called bis(2-ethylhexyl) cyclohexane-1,4-dicarboxylate (Eco-DEHCH), which is an ecofriendly and biologically less harmful replacer. Groups of 50 male and 50 female Han Wistar rats were fed Eco-DEHCH at daily doses of 1,600, 5,000, or 16,000 ppm in their diet for at least 104 weeks. The rats were regularly monitored for mortality, clinical signs, body weight, food consumption, food efficiency, and perceivable mass. All animals were subjected to complete necropsy and histopathological examination. The results indicate that the rats well tolerated chronic exposure to Eco-DEHCH at highest daily doses of 16,000 ppm, with was equivalent to 805.1 mg/kg/day in males and 1060.6 mg/kg/day in females and did not show signs of toxicity or carcinogenicity. In conclusion, Eco-DEHCH could be a safe and promising alternative plasticizer.

Anti-4-1BB×PDL1 Bispecific Antibody Reinvigorates Tumor-Specific Exhausted CD8+ T Cells and Enhances the Efficacy of Anti-PD1 Blockade.

PURPOSE: To overcome the limited efficacy of immune checkpoint blockade, there is a need to find novel cancer immunotherapeutic strategies for the optimal treatment of cancer. The novel anti-4-1BB×PDL1 bispecific antibody-ABL503 (also known as TJ-L14B)-was designed to simultaneously target PDL1 and 4-1BB and demonstrated strong antitumor T-cell responses without considerable toxicity. In this study, we investigated the mechanisms by which the combination of ABL503 and anti-PD1 blockade affected the reinvigoration of exhausted tumor-infiltrating CD8+ T cells (CD8+ TIL) and antitumor efficacy. EXPERIMENTAL DESIGN: Single-cell suspensions of hepatocellular carcinoma and ovarian cancer tissues from treatment-naïve patients were used for immunophenotyping of CD8+ TILs and in vitro functional assays. Humanized hPD1/hPDL1/h4-1BB triple-knock-in mice were used to evaluate the effects of ABL503 and anti-PD1 blockade in vivo. RESULTS: We observed that ABL503 successfully restored the functions of 4-1BB+ exhausted CD8+ TILs, which were enriched for tumor-specific T cells but unresponsive to anti-PD1 blockade. Importantly, compared with anti-PD1 blockade alone, the combination of ABL503 and anti-PD1 blockade further enhanced the functional restoration of human CD8+ TILs in vitro. Consistently, the combination of ABL503 with anti-PD1 in vivo significantly alleviated tumor growth and induced enhanced infiltration and activation of CD8+ TILs. CONCLUSIONS: ABL503, a PDL1 and 4-1BB dual-targeting bispecific antibody, elicits pronounced additive tumor growth inhibition, with increased infiltration and functionality of exhausted CD8+ T cells, which in turn enhances the anticancer effects of anti-PD1 blockade. These promising findings suggest that ABL503 (TJ-L14B) in combination with PD1 inhibitors will likely further enhance therapeutic benefit in clinical trials. See related commentary by Molero-Glez et al., p. 3971.

Combination of PD-1 Checkpoint Blockade and Botulinum Toxin Type A1 Improves Antitumor Responses in Mouse Tumor Models of Melanoma and Colon Carcinoma.

BACKGROUND: Tumor innervation has been shown to be utilized by some solid cancers to support tumor initiation, growth, progression, and metastasis, as well as confer resistance to immune checkpoint blockade through suppression of antitumor immunologic responses. Since botulinum neurotoxin type A1 (BoNT/A1) blocks neuronal cholinergic signaling, its potential use as an anticancer drug in combination with anti-PD-1 therapy was investigated in four different syngeneic mouse tumor models. METHODS: Mice implanted with breast (4T1), lung (LLC1), colon (MC38), and melanoma (B16-F10) tumors were administered a single intratumoral injection of 15 U/kg BoNT/A1, repeated intraperitoneal injections of 5 mg/kg anti-PD-1 (RMP1-14), or both. RESULTS: Compared to the single-agent treatments, anti-PD-1 and BoNT/A1 combination treatment elicited significant reduction in tumor growth among B16-F10 and MC38 tumor-bearing mice. The combination treatment also lowered serum exosome levels in these mice compared to the placebo control group. In the B16-F10 syngeneic mouse tumor model, anti-PD-1 + BoNT/A1 combination treatment lowered the proportion of MDSCs, negated the increased proportion of Treg cells, and elicited a higher number of tumor-infiltrating CD4+ and CD8+ T lymphocytes into the tumor microenvironment compared to anti-PD-1 treatment alone. CONCLUSION: Our findings demonstrate the synergistic antitumor effects of BoNT/A1 and PD-1 checkpoint blockade in mouse tumor models of melanoma and colon carcinoma. These findings provide some evidence on the potential application of BoNT/A1 as an anticancer drug in combination with immune checkpoint blockade and should be further explored.

Carcinogenicity assessment of tegoprazan in Sprague-Dawley (Crl:CD) rats and ICR (Crl:CD1) mice.

Tegoprazan is a novel potassium-competitive acid blocker (P-CAB) that reversibly inhibits the proton pump in gastric parietal cells and has been approved for the treatment of acid-related diseases in Korea. This study aimed to evaluate the carcinogenic potential of tegoprazan in Sprague-Dawley rats and CD-1 mice. Tegoprazan was administered daily by oral gavage to rats for up to 94 weeks and mice for up to 104 weeks. Evidence of carcinogenic potential of tegoprazan was identified in rats only and was limited to benign and/or malignant neuroendocrine cell tumors at exposures >7-fold of the recommended human dose. Glandular stomach findings were considered secondary to the expected pharmacology of tegoprazan, characterized by their location in the fundic and body regions of the stomach. Overall, tegoprazan induced gastric enterochromaffin-like (ECL) cell tumors in SD rats, but did not produce any treatment-related statistically significant increase in the incidence of neoplasms relevant to humans when administered to SD rats and CD-1 mice by gavage at doses up to 300 and 150 mg/kg/day, respectively. Gastric ECL cell tumors are thought to be induced by the exaggerated indirect pharmacological effect of tegoprazan, similar to that reported for proton pump inhibitors (PPIs) and other P-CABs.

A Selective Adenosine A3 Receptor Antagonist, HL3501, Has Therapeutic Potential in Preclinical Liver and Renal Fibrosis Models.

BACKGROUND/AIM: Adenosine and 4 G-protein-associated membrane receptors (A1, A2A, A2B, and A3) and their derivatives regulate the central nervous, cardiovascular, peripheral, and immune system. We developed a novel selective A3 AR antagonist, HL3501, and examined its anti-fibrotic effects across various models. MATERIALS AND METHODS: The anti-fibrotic activity of HL3501 was evaluated in three cell lines (HK2, LX2, and Primary hepatic stellate cell) and a methionine-choline-deficient (MCD) model including use of mouse pharmacokinetics (PK). RESULTS: HL3501 decreased alpha-smooth muscle actin (α-SMA) and collagen 1 in TGF-ß1-induced pro-fibrotic activation in HK2 cells. HL3501 also inhibited TGF-ß1-induced HSC activation, which resulted in reduction of α-SMA and fibronectin in LX2 and human primary HSCs. In the nonalcoholic fatty liver disease activity score (NAS) analysis, HL3501 showed improved anti-steatosis and anti-inflammatory activity. The mouse PK study revealed the oral bioavailability (%F) of HL3501 at 30 mg/kg and 60 mg/kg as 92.5 and 107.2%, respectively. CONCLUSION: HL3501 presents anti-fibrotic effects in in vitro and in vivo studies. We also demonstrated that HL3501 is orally available and has a good bioavailability (BA >90%) profile from in mouse PK. HL3501, therefore, has a therapeutic potential for various fibrotic diseases, including those of liver and kidney tissues.

HL3501, a Novel Selective A3 Adenosine Receptor Antagonist, Lowers Intraocular Pressure (IOP) in Animal Glaucoma Models.

PURPOSE: The A3 adenosine receptor (A3AR) is a known therapeutic target for glaucoma treatment. In this study, we developed HL3501 and examined its selectivity profile and in vitro and in vivo effects. METHODS: For the rabbit model, intraocular pressure (IOP) was increased by laser photocoagulation of the trabecular meshwork (TM). The rabbits were then topically treated with HL3501, latanoprost, timolol, or vehicle for 3 weeks. For the mouse model, HL3501, latanoprost, or vehicle was administered following induced IOP elevation by dexamethasone (Dex). The IOP of all rabbits and mice was measured. Electroretinography was performed on both eyes of dark-adapted anesthetized mice on days 0 and 21. The mice's eyes were enucleated at the end of the treatment for immunofluorescence staining. RESULTS: HL3501 was highly specific to the A3AR and inhibitory of A3AR function. In the rabbit glaucoma model, HL3501 and latanoprost significantly decreased the IOP. In the Dex-treated mouse model, HL3501 and latanoprost significantly decreased the IOP and increased the b-wave amplitude as compared with the vehicle treatment. HL3501 and latanoprost also inhibited fibronectin and α-smooth muscle actin expression induced by Dex treatment. CONCLUSIONS: HL3501 had effects similar to those of latanoprost in reducing ocular hypertension in animal models. HL3501 could be used as a novel approach to treat glaucoma. TRANSLATIONAL RELEVANCE: HL3501 is a novel preclinical compound targeting the A3 adenosine receptor, which may also be a new treatment option to fill the unmet needs of many glaucoma patients.

CKD-506: A novel HDAC6-selective inhibitor that exerts therapeutic effects in a rodent model of multiple sclerosis.

Despite advances in therapeutic strategies for multiple sclerosis (MS), the therapy options remain limited with various adverse effects. Here, the therapeutic potential of CKD-506, a novel HDAC6-selective inhibitor, against MS was evaluated in mice with myelin oligodendrocyte glycoprotein35-55 (MOG35-55)-induced experimental autoimmune encephalitis (EAE) under various treatment regimens. CKD-506 exerted prophylactic and therapeutic effects by regulating peripheral immune responses and maintaining blood-brain barrier (BBB) integrity. In MOG35-55-re-stimulated splenocytes, CKD-506 decreased proliferation and downregulated the expression of IFN-γ and IL-17A. CKD-506 downregulated the levels of pro-inflammatory cytokines in the blood of EAE mice. Additionally, CKD-506 decreased the leakage of intravenously administered Evans blue into the spinal cord; CD4+ T cells and CD4-CD11b+CD45+ macrophage/microglia in the spinal cord was also decreased. Moreover, CKD-506 exhibited therapeutic efficacy against MS, even when drug administration was discontinued from day 15 post-EAE induction. Disease exacerbation was not observed when fingolimod was changed to CKD-506 from day 15 post-EAE induction. CKD-506 alleviated depression-like behavior at the pre-symptomatic stage of EAE. In conclusion, CKD-506 exerts therapeutic effects by regulating T cell- and macrophage-mediated peripheral immune responses and strengthening BBB integrity. Our results suggest that CKD-506 is a potential therapeutic agent for MS.

Association between ARID2 and RAS-MAPK pathway in intellectual disability and short stature.

BACKGROUND: ARID2 belongs to the Switch/sucrose non-fermenting complex, in which the genetic defects have been found in patients with dysmorphism, short stature and intellectual disability (ID). As the phenotypes of patients with ARID2 mutations partially overlap with those of RASopathy, this study evaluated the biochemical association between ARID2 and RAS-MAPK pathway. METHODS: The phenotypes of 22 patients with either an ARID2 heterozygous mutation or haploinsufficiency were reviewed. Comprehensive molecular analyses were performed using somatic and induced pluripotent stem cells (iPSCs) of a patient with ARID2 haploinsufficiency as well as using the mouse model of Arid2 haploinsufficiency by CRISPR/Cas9 gene editing. RESULTS: The phenotypic characteristics of ARID2 deficiency include RASopathy, Coffin-Lowy syndrome or Coffin-Siris syndrome or undefined syndromic ID. Transient ARID2 knockout HeLa cells using an shRNA increased ERK1 and ERK2 phosphorylation. Impaired neuronal differentiation with enhanced RAS-MAPK activity was observed in patient-iPSCs. In addition, Arid2 haploinsufficient mice exhibited reduced body size and learning/memory deficit. ARID2 haploinsufficiency was associated with reduced IFITM1 expression, which interacts with caveolin-1 (CAV-1) and inhibits ERK activation. DISCUSSION: ARID2 haploinsufficiency is associated with enhanced RAS-MAPK activity, leading to reduced IFITM1 and CAV-1 expression, thereby increasing ERK activity. This altered interaction might lead to abnormal neuronal development and a short stature.

PKM2 in Canine Mammary Tumors: Parallels to Human Breast Cancer.

PKM2 is a pyruvate kinase isoform that is the final and rate-limiting step in aerobic glycolysis in tumor cells. Increased expression of PKM2 has been detected in human cancers. The present study examined the expression of PKM2 in canine mammary tumors and assessed its prognostic significance. Paraffin sections of 5 adenomas, 67 carcinomas, and 5 samples of nonneoplastic hyperplasia from 77 dogs, aged 8 to 18 y, were evaluated. Significantly higher levels of PKM2 were detected among the carcinomas compared with all other tissues examined. The level of PKM2 expression in carcinoma tissue correlated positively with the tumor grade. These findings suggest that PKM2 may have a similar role in canine mammary tumors to its role in human breast cancer. As such, canine mammary tumors may be useful models for studies focused on the progression of human neoplastic disease.

Use of 3D Human Liver Organoids to Predict Drug-Induced Phospholipidosis.

Drug-induced phospholipidosis (PL) is a storage disorder caused by the formation of phospholipid-drug complexes in lysosomes. Because of the diversity of PL between species, human cell-based assays have been used to predict drug-induced PL in humans. We established three-dimensional (3D) human liver organoids as described previously and investigated their liver characteristics through multiple analyses. Drug-induced PL was initiated in these organoids and in monolayer HepG2 cultures, and cellular changes were systemically examined. Organoids that underwent differentiation showed characteristics of hepatocytes rather than HepG2 cells. The organoids also survived under PL-inducing drug conditions for 48 h and maintained a more stable albumin secretion level than the HepG2 cells. More cytoplasmic vacuoles were observed in organoids and HepG2 cells treated with more potent PL-induced drugs, but to a greater extent in organoids than in HepG2 cells. Lysosome-associated membrane protein 2, a marker of lysosome membranes, showed a stronger immunohistochemical signal in the organoids. PL-distinctive lamellar bodies were observed only in amiodarone-treated organoids by transmission electron microscopy. Human liver organoids are thus more sensitive to drug-induced PL and less affected by cytotoxicity than HepG2 cells. Since PL is a chronic condition, these results indicate that organoids better reflect metabolite-mediated hepatotoxicity in vivo and could be a valuable system for evaluating the phospholipidogenic effects of different compounds during drug development.

Subretinal transplantation of human embryonic stem cell-derived retinal pigment epithelium (MA09-hRPE): A safety and tolerability evaluation in minipigs.

This study aimed to determine the safety and tolerability of the subretinal injection of hESC-derived RPE cells at higher doses than the established clinical dose (5 × 104 cells/150 µL) by using minipigs. The hESC-derived RPE cells (60 or 120 × 104 cells/150 µL) were injected in subretinal region, and minipigs were sacrificed at Weeks 4, 8, and 12 post-surgery. Time-course examination was performed by using fundus photography, optical coherence tomography (OCT), histopathology, and fluorescence in situ hybridization (FISH). After surgery, retinal bleb and pigmentation were seen and retinal bleb became smaller gradually. In histopathology, cell clusters consisting of a uniform population of the round to oval cells were seen at the subretinal injection site. In immunohistochemistry, most of the cells were positive for anti-CD3 and CD45 antibodies but negative for anti-human nuclei antibody; transplanted cells were not detectable by DNA probe in FISH assay. Cell clusters were thought to be a host immune response to trauma or transplanted cells. There were no other changes related to subretinal RPE cell injection. These results suggested that subretinal injection of hESC-derived RPE cells (60 and 120 × 104 cells/150 µL) in minipigs is well-tolerated and safe.

Metronomic oral doxorubicin in combination of Chk1 inhibitor MK-8776 for p53-deficient breast cancer treatment.

Metronomic chemotherapy, which is defined as a low-dose and frequent administration of cytotoxic drugs without drug-free breaks, has been recently emerged as an alternative to traditional MTD therapy and has shown therapeutic benefit in breast cancer patients in numbers of clinical studies. Unlike MTD, metronomic chemotherapy acts by multiple mechanisms including antiangiogenic effect and immunomodulation, but the direct cytotoxic effect only playing a minor role due to the lowered dose. In this light, within the limits of p53-deficient breast cancer, we demonstrate the enhanced anticancer effect of metronomic chemotherapy using doxorubicin when combined with Chk1 inhibitor MK-8776 by specifically augmenting the direct cytotoxic effect on cancer cells. Since the oral drug is greatly favored in metronomic chemotherapy due to the frequent and potential long-term administration, we prepared an oral doxorubicin by producing an ionic complex with deoxycholic acid, which showed sufficient bioavailability and anticancer effect when administered orally. MK-8776 selectively enhanced the cytotoxic effect of low-concentration doxorubicin in p53-deficient breast cancer cells by abrogating the Chk1-dependent cell cycle arrest in vitro. Consistently, combining MK-8776 significantly improved the anticancer effect of the daily administered oral doxorubicin in p53-deficient breast cancer xenografts especially in a lower dose of doxorubicin without evident systemic toxicities. Combination therapy of MK-8776 and metronomic oral doxorubicin would be thus promising in the treatment of p53-deficient breast cancer benefited from the augmented direct cytotoxic effect and low risk of toxicities.

C1q/TNF-α-Related Protein 1 (CTRP1) Maintains Blood Pressure Under Dehydration Conditions.

RATIONALE: Circulating CTRP1 (C1q/TNF-α [tumor necrosis factor-α]-related protein 1) levels are increased in hypertensive patients compared with those in healthy subjects. Nonetheless, little is known about the molecular and physiological function of CTRP1 in blood pressure (BP) regulation. OBJECTIVE: To investigate the physiological/pathophysiological role of CTRP1 in BP regulation. METHODS AND RESULTS: CTRP1 production was increased to maintain normotension under dehydration conditions, and this function was impaired in inducible CTRP1 KO (knockout) mice (CTRP1 ΔCAG). The increase in CTRP1 under dehydration conditions was mediated by glucocorticoids, and the antagonist mifepristone prevented the increase in CTRP1 and attenuated BP recovery. Treatment with a synthetic glucocorticoid increased the transcription, translation, and secretion of CTRP1 from skeletal muscle cells. Functionally, CTRP1 increases BP through the stimulation of the AT1R (Ang II [angiotensin II] receptor 1)-Rho (Ras homolog gene family)/ROCK (Rho kinase)-signaling pathway to induce vasoconstriction. CTRP1 promoted AT1R plasma membrane trafficking through phosphorylation of AKT and AKT substrate of 160 kDa (AS160). In addition, the administration of an AT1R blocker, losartan, recovered the hypertensive phenotype of CTRP1 TG (transgenic) mice. CONCLUSIONS: For the first time, we provide evidence that CTRP1 contributes to the regulation of BP homeostasis by preventing dehydration-induced hypotension.

Development of a Mouse Model of Prostate Cancer Using the Sleeping Beauty Transposon and Electroporation.

The Sleeping Beauty (SB) transposon system is non-viral and uses insertional mutagenesis, resulting in the permanent expression of transferred genes. Although the SB transposon is a useful method for establishing a mouse tumor model, there has been difficulty in using this method to generate tumors in the prostate. In the present study, electroporation was used to enhance the transfection efficiency of the SB transposon. To generate tumors, three constructs (a c-Myc expression cassette, a HRAS (HRas proto-oncogene, GTPase) expression cassette and a shRNA against p53) contained within the SB transposon plasmids were directly injected into the prostate. Electroporation was conducted on the injection site after the injection of the DNA plasmid. Following the tumorigenesis, the tumors were monitored by animal PET imaging and identified by gross observation. After this, the tumors were characterized by using histological and immunohistochemical techniques. The expression of the targeted genes was analyzed by Real-Time qRT-PCR. All mice subjected to the injection were found to have prostate tumors, which was supported by PSA immunohistochemistry. To our knowledge, this is the first demonstration of tumor induction in the mouse prostate using the electroporation-enhanced SB transposon system in combination with c-Myc, HRAS and p53. This model serves as a valuable resource for the future development of SB-induced mouse models of cancer.

EZH2 Expression in Naturally Occurring Canine Tumors.

Enhancer of zeste homolog 2 (EZH2) shows upregulated expression in tumors and is an important driver of tumor development and progression. However, the mechanism underlying the mediation of tumor aggressiveness by EZH2 remains unclear. We here investigated the levels of EZH2 in various normal and tumorous dog tissues and compared these patterns with those of the corresponding human tissues. Immunohistochemical analysis showed positive staining for EZH2 in 76 of 82 cases of canine tumors, whereas low or negligible staining occurred in normal tissues and other canine tumors, including hepatocellular adenoma and lipoma. In particular, canine lymphoma, melanoma, basal cell tumors, squamous cell carcinoma, and prostate cancer all show EZH2 overexpression, as do their human counterparts. Given the similarities of spontaneous canine tumors to human cancers, we believe that these canine tumors can be used as animal models in future research and clinical trials in the development of EZH2 inhibitors.

Efficacy of HL036 versus Cyclosporine A in the Treatment of Naturally Occurring Canine Keratoconjunctivitis Sicca.

PURPOSES: To (i) evaluate the efficacy and safety of HL036, a tumor-necrosis factor (TNF)-α-blocking protein, in the treatment of naturally occurring canine keratoconjunctivitis sicca (KCS) and (ii) compare these features with those of 1% cyclosporine A (CsA). MATERIALS AND METHODS: Dogs (n = 29) diagnosed with KCS were randomly assigned to receive one drop topical aqueous HL036 (0.2, 1, or 5 mg/mL) or 1% CsA in the affected eye(s) at 12-h intervals for 42 days. Schirmer's tear test (STT), fluorescein corneal staining (FCS), and clinical-sign scores were evaluated prior to application (day-0) and on days 14, 28, and 42 post-treatment. Of the 29 dogs enrolled, 19 (65.5%) received HL036 (HL036 group) and 10 (34.5%) received 1% CsA (CsA group). A linear mixed-effects model analysis was performed to determine score differences between groups and over time. RESULTS: After treatment, clinical-sign scores and STT values had significantly improved compared with baseline levels in dogs of both treatment groups. Decreases in total clinical-sign scores for the HL036-group were greater than those of 1% CsA group. No severe adverse reactions were noted in either group. CONCLUSIONS: Our findings suggest that topical aqueous HL036 is well-tolerated and more effective than 1% CsA for treating naturally occurring canine KCS.

Biocompatibility and Efficiency of Biodegradable Magnesium-Based Plates and Screws in the Facial Fracture Model of Beagles.

PURPOSE: A biodegradable magnesium alloy system has been developed as a substitute for conventional plates and screws made of titanium or absorbable polymer. However, previous studies were limited to small animal experiments using screws or wires. In the present study, we preliminarily evaluated the biocompatibility and effectiveness of human standard-size biodegradable magnesium-based plates and screws in facial fractures of beagles. MATERIALS AND METHODS: Fracture lines were created bilaterally in the zygomatic arches of 6 beagles. They were fixed in situ with plates and screws made of magnesium alloy mixed with calcium and zinc (experimental group) or absorbable polymer (control group). Laboratory testing, radiologic imaging, histologic analysis, and mechanical testing were performed 4 weeks postoperatively. RESULTS: Inflammatory reactions were not significantly increased in any animal. Mechanical testing showed greater ultimate load and structural stiffness in the experimental group. In the histologic analysis, the void area and bone regeneration area were increased in the experimental, and the implant area and soft tissue area were increased in the control group. Radiologically, 3-dimensional micro-computed tomography showed no differences in the bone gap area between the 2 groups. A temporary increase in hydrogen gas around the magnesium implants regressed spontaneously and did not affect bone healing significantly. CONCLUSIONS: Magnesium-based biodegradable plates and screws showed good biocompatibility and offered considerable stability for fixating facial bone fractures in the early bone-healing process. These results show the possibilities for the future development of magnesium alloy plates and screws for craniomaxillofacial fixation in humans.

Sirolimus-eluting Biodegradable Poly-l-Lactic Acid Stent to Suppress Granulation Tissue Formation in the Rat Urethra.

Purpose To investigate the use of sirolimus-eluting biodegradable stents (SEBSs) to suppress granulation tissue formation after stent placement in a rat urethral model. Materials and Methods All experiments were approved by the animal research committee. A total of 36 male Sprague-Dawley rats were randomized into three equal groups after biodegradable stent placement. Group A received control biodegradable stents. Groups B and C received stents coated with 90 µg/cm2 and 450 µg/cm2 sirolimus, respectively. Six rats in each group were sacrificed after 4 weeks; the remaining rats were sacrificed after 12 weeks. The therapeutic effectiveness of SEBSs was assessed by comparing the results of retrograde urethrography and histologic examination. Analysis of variance with post hoc comparisons was used to evaluate statistical differences. Results SEBS placement was technically successful in all rats. Urethrographic and histologic examinations revealed significantly less granulation tissue formation at both time points in the rats receiving SEBSs (groups B and C) compared with those that received control stents (group A) (P < .05 for all). There were no significant differences in urethrographic and histologic findings between groups B and C (P > .05 for all). However, the mean number of epithelial layers in group B was higher than that in group C at 4 weeks after stent placement (P < .001). Apoptosis increased in group C compared with groups A and B (P < .05 for all). Conclusion The use of SEBSs suppressed granulation tissue formation secondary to stent placement in a rat urethral model; local therapy with SEBSs may be used to decrease stent-related granulation tissue formation. © RSNA, 2017.

Green tea extracts for the prevention of metachronous colorectal polyps among patients who underwent endoscopic removal of colorectal adenomas: A randomized clinical trial.

OBJECTIVES: To determine the preventive effect of green tea extract (GTE) supplements on metachronous colorectal adenoma and cancer in the Korean population. MATERIALS AND METHODS: One hundred seventy-six subjects (88 per each group) who had undergone complete removal of colorectal adenomas by endoscopic polypectomy were enrolled. They were randomized into 2 groups: supplementation group (0.9 g GTE per day for 12 months) or control group without GTE supplementation. The 72-h recall method was used to collect data on food items consumed by participants at baseline and the 1-year follow-up during the past 48 h. Follow-up colonoscopy was conducted 12 months later in 143 patients (71 in control group and 72 in the GTE group). RESULTS: Of the 143 patients completed in the study, the incidences of metachronous adenomas at the end-point colonoscopy were 42.3% (30 of 71) in control group and 23.6% (17 of 72) in GTE group (relative risk [RR], 0.56; 95% confidence interval [CI], 0.34-0.92). The number of relapsed adenoma was also decreased in the GTE group than in the control group (0.7 ± 1.1 vs. 0.3 ± 0.6, p = 0.010). However, there were no significant differences between the 2 groups in terms of body mass index, dietary intakes, serum lipid profiles, fasting serum glucose, and serum C-reactive protein levels (all p > 0.05). CONCLUSION: This study of GTE supplement suggests a favorable outcome for the chemoprevention of metachronous colorectal adenomas in Korean patients (ClinicalTrials.gov number, NCT02321969).

Renal oncocytoma in a cat with chronic renal failure.

CASE SUMMARY: A 9-year-old male neutered domestic shorthair cat presented with anorexia. Ultrasonography showed an irregularly shaped hypoechoic mass in the cranial pole of the right kidney. Ultrasound-guided fine-needle aspiration of the renal mass was performed. Cytology revealed moderate cellularity smears composed of epithelial cell clusters, which consisted of an exclusive population of oncocytic cells seen in sheets and papillary clusters along with abundant single cells. A moderate-to-abundant amount of densely stained granular cytoplasm with round nuclei and indistinct nucleoli was seen. The cytological diagnosis was renal oncocytic neoplasm. CT and surgical resection revealed a firm tan mass in the right kidney. A final diagnosis of renal oncocytoma was made on the basis of histology, immunohistochemical staining profile (positive for cytokeratin, and negative for chromogranin A, neuron-specific enolase and vimentin) of neoplastic cells, together with the electronic microscopy results. RELEVANCE AND NOVEL INFORMATION: We believe that this is the first report of the cytological features of feline renal oncocytoma.