KAT2 paralogs prevent dsRNA accumulation and interferon signaling to maintain intestinal stem cells.

Histone acetyltransferases KAT2A and KAT2B are paralogs highly expressed in the intestinal epithelium, but their functions are not well understood. In this study, double knockout of murine Kat2 genes in the intestinal epithelium was lethal, resulting in robust activation of interferon signaling and interferon-associated phenotypes including the loss of intestinal stem cells. Use of pharmacological agents and sterile organoid cultures indicated a cell-intrinsic double-stranded RNA trigger for interferon signaling. Acetyl-proteomics and dsRIP-seq were employed to interrogate the mechanism behind this response, which identified mitochondria-encoded double-stranded RNA as the source of intrinsic interferon signaling. Kat2a and Kat2b therefore play an essential role in regulating mitochondrial functions as well as maintaining intestinal health.

Inhibition of corneal neovascularization by subconjunctival and topical bevacizumab and sunitinib in a rabbit model.

PURPOSE: To compare the effects of subconjunctival injection and topical application of bevacizumab and sunitinib on experimentally induced corneal neovascularization (CNV). METHODS: CNV was induced by sutures in the right eyes of 36 rabbits. After suture removal, the rabbits were divided into 6 groups with 6 rabbits in each group. In groups 1, 2, and 3, the eyes received a subconjunctival injection of 0.1 mL of normal saline, 2.5 mg/0.1 mL of bevacizumab, and 0.25 mg/0.1 mL of sunitinib, respectively, immediately after suture removal. A booster injection of the same agent was repeated 1 week later in each group. In groups 4, 5, and 6, the eyes received topical applications of saline, bevacizumab (5 mg/mL), and sunitinib (0.5 mg/mL), respectively. These solutions were applied twice a day for 2 weeks, starting immediately after suture removal. CNV was analyzed through biomicroscopy and through histological examination using hematoxylin and eosin and CD31 immunohistochemical staining. RESULTS: On day 14, the mean percentages of areas of CNV in sunitinib-treated eyes were smaller compared with saline-treated or bevacizumab-treated eyes in both the subconjunctival (P = 0.003 and 0.032, respectively) and topical groups (P < 0.001 in both). The topical administration of sunitinib was significantly more effective than the subconjunctival injection of the same drug at 1 week (P = 0.011). Upon histological examination of samples from the topical group, sunitinib-treated eyes showed lower vascularity than saline-treated and bevacizumab-treated eyes (P = 0.036 and 0.046, respectively). CONCLUSIONS: These results suggest that sunitinib is more effective than bevacizumab for the inhibition of CNV. Furthermore, topical administration of sunitinib yields better results than a subconjunctival injection of the same medication.

The role of Nod1 signaling in corneal neovascularization.

PURPOSE: Corneal neovascularization (CNV) is associated with Chlamydia trachomatis. The minimal components of bacterial cell walls are recognized by nucleotide-binding oligomerization domain-containing protein (Nod), which is important for host defense--a mechanism manifested in human corneal cells. We aimed to examine whether Nod stimulation is associated with CNV. METHODS: Three groups of mice with alkali-induced CNV were topically treated with tripeptide L-Ala-γ-D-Glu-meso-diaminopimelic acid (Tri-DAP, a Nod1 agonist), muramyl dipeptide (a Nod2 agonist), or phosphate-buffered saline twice daily for 8 days. The time course responses were quantified using biomicroscopic examinations and immunohistochemistry. Angiogenic factor expression was evaluated by quantitative real-time reverse transcription-polymerase chain reaction. To confirm the involvement of Nod1 signaling in CNV, RICK (an essential molecule in Nod signaling)-knockout mice treated with Tri-DAP were examined biomicroscopically and immunohistochemically 8 days after injury. RESULTS: According to the biomicroscopic camera images and histology, Tri-DAP and muramyl dipeptide promoted CNV. Significantly, Tri-DAP increased the number and size of the neovascularized areas. The messenger RNA expression level of vascular endothelial growth factor was elevated in the Tri-DAP-treated mice after alkali injury. Compared with wild-type mice, CNV was attenuated in RICK-deficient mice treated with Tri-DAP. CONCLUSIONS: These data suggest that Nod1 stimulation is an important inducer of CNV and that Nod1 might be useful in the development of CNV therapies.

Genome-wide combination profiling of DNA copy number and methylation for deciphering biomarkers in non-small cell lung cancer patients.

Early detection of lung cancer provides the highest potential for saving lives. To date, no routine screening method enabling early detection is available, which is a key factor in the disease's high mortality rate. Copy number changes and DNA methylation alterations are good indicators of carcinogenesis and cancer prognosis. In this study, we attempted to combine profiles of DNA copy number and methylation patterns in 20 paired cancerous and noncancerous tissue samples from non-small cell lung cancer (NSCLC) patients, and we detected several clinically important genes with genetic and epigenetic relationships. Using array comparative genomic hybridization (aCGH), statistically significant differences were observed across the histological subtypes for gains at 1p31.1, 3q26.1, and 3q26.31-3q29 as well as for losses at 1p21.1, 2q33.3, 2q37.3, 3p12.3, 4q35.2, and 13q34 in squamous cell carcinoma (SQ) patients, and losses at 12q24.33 were measured in adenocarcinoma (AD) patients (p < 0.05). In an analysis of DNA methylation at 1505 autosomal CpG loci that are associated with 807 cancer-related genes, we identified six and nine loci with higher and lower DNA methylation levels, respectively, in tumor tissue compared to non-tumor lung tissues from AD patients. In addition, three loci with higher and seven loci with lower DNA methylation levels were identified in tumor tissue from SQ patients compared to non-tumor lung tissue. Subsequently, we searched for regions exhibiting concomitant hypermethylation and genomic loss in both ADs and SQs. One clone representing 7p15.2 (which includes candidate genes such as HOXA9 and HOXA11) and one target ID representing HOXA9_E252_R were detected. Quantitative real-time PCR identified the potential candidate gene HOXA9 as being down-regulated in the majority of NSCLC patients. Moreover, following HOXA9 over-expression, the invasion of representative cell lines, A549 and HCC95, were significantly inhibited. Taken together, our results show that the combined profiling analysis technique is a useful tool for identifying biomarkers in lung cancer and that HOXA9 might be a potential candidate gene for the pathogenesis and diagnosis of NSCLC patients.