Different transcriptome profiles between human retinoblastoma Y79 cells and an etoposide-resistant subline reveal a chemoresistance mechanism.

BACKGROUND: Retinoblastoma (RB) is the most frequent pediatric retinal tumor. In the present study, to elucidate chemoresistance mechanisms and identify potential biomarkers in RB, we utilized RNA sequencing (RNAseq) technological platforms to reveal transcriptome profiles and identify any differentially expressed genes (DEGs) between an etoposide drug-resistant subline (Y79/EDR) and parental Y79 cells. METHODS: To test whether Y79/EDR cells showed resistance to antineoplastic agents for RB, we treated the cells with etoposide, carboplatin and vincristine and analyzed them with a Cell Counting Kit-8 (CCK-8). Y79/EDR and parental Y79 cells were used for RNAseq and bioinformatics analysis to enable a genome-wide review of DEGs between the two lines using the DESeq R package (1.10.1). Then, DEG enrichment in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways was analyzed with KOBAS software. Next, real-time quantitative reverse transcription polymerase chain reaction (real time QRT-PCR) and cytotoxicity assays were performed to experimentally and functionally validate the identified candidate biomarkers. RESULTS: Y79/EDR cells showed resistance to etoposide, carboplatin and vincristine at different concentrations. In total, 524 transcripts were differentially expressed in Y79/EDR cells based on analysis of fragments per kilobase of transcript per million fragments mapped (FPKM); among these, 57 genes were downregulated and 467 genes were upregulated in Y79/EDR cells compared to parental Y79 cells. We selected candidate DEGs, including ARHGAP9, HIST1H4H, RELN, DDIT4, HK2, STC1 and PFKFB4, for mRNA expression validation with real time QRT-PCR assays and found that the expression levels determined by real time QRT-PCR were consistent with the RNAseq data. Further studies involving downregulation of ARHGAP9 with a specific siRNA showed that ARHGAP9 altered the cellular sensitivity of Y79 cells to etoposide and carboplatin. CONCLUSION: Our initial findings provided a genomic view of the transcription profiles of etoposide-induced acquired resistance in RB. Follow-up studies indicated that ARHGAP9 might be a chemoresistance biomarker in RB, providing insight into potential therapeutic targets for overcoming acquired chemoresistance in RB. These findings can aid in understanding and overcoming chemoresistance during treatment of RB in the clinic.

Full-Term Neonatal Ophthalmic Screening in China: A Review of 4-Year Outcomes.

BACKGROUND AND OBJECTIVE: To report the 4-year outcomes of a neonatal ophthalmic screening program in the Kunming Maternity and Child Care Hospital of Kunming City, Kunming, China. PATIENTS AND METHODS: This was a retrospective, observational case series study. Newborns who underwent neonatal eye screening using the RetCam system (Clarity Medical Systems, Pleasanton, CA) at the authors' hospital from March 2010 to February 2014 were included. RESULTS: Of the 15,284 full-term infants who participated in the program, 21% (3,171 of 15,284) had some ocular abnormalities. Among these abnormalities, retinal hemorrhage was the most frequent finding, accounting for 19% (2,899 of 15,284) of all cases. Other anomalies were found in 2% (272 of 15,284) of the cases. No major ocular or systemic complications were found to be associated with the screening process. CONCLUSION: Overall, 21% of the newborns who underwent the eye screening program were found to have an abnormality. The use of the RetCam for the screening program was both efficient and safe in identifying ocular anomalies. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:983-992.].

Comparison of Color Fundus Photography, Infrared Fundus Photography, and Optical Coherence Tomography in Detecting Retinal Hamartoma in Patients with Tuberous Sclerosis Complex.

BACKGROUND: A sensitive method is required to detect retinal hamartomas in patients with tuberous sclerosis complex (TSC). The aim of the present study was to compare the color fundus photography, infrared imaging (IFG), and optical coherence tomography (OCT) in the detection rate of retinal hamartoma in patients with TSC. METHODS: This study included 11 patients (22 eyes) with TSC, who underwent color fundus photography, IFG, and spectral-domain OCT to detect retinal hamartomas. TSC1 and TSC2RESULTS: The mean age of the 11 patients was 8.0 ± 2.1 years. The mean spherical equivalent was -0.55 ± 1.42 D by autorefraction with cycloplegia. In 11 patients (22 eyes), OCT, infrared fundus photography, and color fundus photography revealed 26, 18, and 9 hamartomas, respectively. The predominant hamartoma was type I (55.6%). All the hamartomas that detected by color fundus photography or IFG can be detected by OCT. CONCLUSION: Among the methods of color fundus photography, IFG, and OCT, the OCT has higher detection rate for retinal hamartoma in TSC patients; therefore, OCT might be promising for the clinical diagnosis of TSC.

Findings of perinatal ocular examination performed on 3573, healthy full-term newborns.

OBJECTIVE: To document the findings of a newborn eye examination programme for detecting ocular pathology in the healthy full-term newborn. METHODS: This is a cross-sectional study of the majority of newborns born in the Kunming Maternal and Child Healthcare Hospital, China, between May 2010 and June 2011. Infants underwent ocular examination within 42 days after birth using a flashlight, retinoscope, hand-held slit lamp microscope and wide-angle digital retinal image acquisition system. The retinal fundus examination utilised the RetCam wide-field digital imaging system (Clarity Medical Systems, Pleasanton, California, USA). The external eye, pupillary light reflex, red reflex, opacity of refractive media, anterior chamber and posterior segments were also examined. RESULTS: A total of 3573 healthy full-term newborns were enrolled and examined in the programme. There was detection of 871 abnormal cases (24.4%). The majority of abnormal exams were 769 (21.52%) retinal haemorrhages. Of these, there were 215 cases of significant retinal haemorrhage, possible sight threatening or amblyogenic, representing 6.02% of the total. In addition, 67 cases (1.88%) involved macular haemorrhage. The other 107 cases (2.99%) with abnormal ocular findings included subconjunctival haemorrhage, congenital microphthalmos, congenital corneal leukoma, posterior synechia, persistent pupillary membrane, congenital cataract, enlarged C/D ratio, retinal hamartoma versus retinoblastoma, optic nerve defects, macular pigment disorder and non-specific peripheral retinopathy. CONCLUSION: Ocular examination of healthy newborns leads to the detection of a significant number of ocular pathologies. The most commonly discovered ocular abnormality during examination of the newborns in this study is retinal haemorrhage. The long-term impact of these findings is unknown. Although presumed by some to benign, neonatal retinal haemorrhages due to birth trauma could be involved in altering visual development. Further work, including prospective examination of newborns with long-term follow-up, is needed and supported by our findings.