DECKO: Single-oligo, dual-CRISPR deletion of genomic elements including long non-coding RNAs.

BACKGROUND: CRISPR genome-editing technology makes it possible to quickly and cheaply delete non-protein-coding regulatory elements. We present a vector system adapted for this purpose called DECKO (Double Excision CRISPR Knockout), which applies a simple two-step cloning to generate lentiviral vectors expressing two guide RNAs (gRNAs) simultaneously. The key feature of DECKO is its use of a single 165 bp starting oligonucleotide carrying the variable sequences of both gRNAs, making it fully scalable from single-locus studies to complex library cloning. RESULTS: We apply DECKO to deleting the promoters of one protein-coding gene and two oncogenic lncRNAs, UCA1 and the highly-expressed MALAT1, focus of many previous studies employing RNA interference approaches. DECKO successfully deleted genomic fragments ranging in size from 100 to 3000 bp in four human cell lines. Using a clone-derivation workflow lasting approximately 20 days, we obtained 9 homozygous and 17 heterozygous promoter knockouts in three human cell lines. Frequent target region inversions were observed. These clones have reductions in steady-state MALAT1 RNA levels of up to 98 % and display reduced proliferation rates. CONCLUSIONS: We present a dual CRISPR tool, DECKO, which is cloned using a single starting oligonucleotide, thereby affording simplicity and scalability to CRISPR knockout studies of non-coding genomic elements, including long non-coding RNAs.

HHV-8-related visceral Kaposi's sarcoma following allogeneic HSCT: report of a pediatric case and literature review.

An HHV-8-related visceral KS was diagnosed in a 10-yr-old boy after partially matched allogeneic HSCT. This complication occurred 463 days after HSCT and involved tonsils, lymph nodes, hard palate, lung, skin, and paranasal sinuses. Treatment with pegylated liposomal doxorubicin induced long-term remission (33 months) of this disease. HHV-8 infection is quite frequent after HSCT, but KS, and especially its visceral form, is a very rare complication, and its association with HHV-8 has been documented even less frequently. However, our observation suggests that HHV-8-related KS should be taken into consideration in the differential diagnosis of late post-HSCT complications.

Achievement of a state of inactive disease at least once in the first 5 years predicts better outcome of patients with polyarticular juvenile idiopathic arthritis.

OBJECTIVE: To investigate whether the achievement of inactive disease in the first 5 years predicts a more favorable outcome of children with juvenile idiopathic arthritis (JIA). METHODS: We reviewed clinical charts of 123 patients who started taking methotrexate, were followed for at least 5 years, and received a yearly assessment in the first 5 years. At each yearly visit, the presence of inactive disease was assessed. Patients were divided into 3 groups: (1) patients who never reached inactive disease; (2) patients who reached inactive disease in only 1 visit; and (3) patients who reached inactive disease in > or = 2 visits. Outcome was evaluated after 6 to 18 years (median 7.1 yrs) by assessing the following clinical measures: restricted joint count, Childhood Health Assessment Questionnaire (CHAQ), Juvenile Arthritis Damage Index (JADI), and Poznanski score of radiographic damage. RESULTS: In the first 5 years, 62 patients (50.4%) were noted to have active disease at their yearly visit, 40 patients (32.5%) were noted to have inactive disease only once, and 21 patients (17.1%) were noted to have inactive disease in > or = 2 visits. Patients who achieved inactive disease 1 or more times had lower restricted joint count (p = 0.007) and JADI-Articular score (p = 0.004) at last followup visit than those who never reached such a state. A similar trend, although not significant, was observed for CHAQ and Poznanski score of radiographic damage. CONCLUSION: Attainment of the state of inactive disease at least once in the first 5 years was found to be associated with less longterm joint damage and with a trend toward less functional impairment.