ABL Genomic Editing Sufficiently Abolishes Oncogenesis of Human Chronic Myeloid Leukemia Cells In Vitro and In Vivo.

Chronic myelogenous leukemia (CML) is the most common type of leukemia in adults, and more than 90% of CML patients harbor the abnormal Philadelphia chromosome (Ph) that encodes the BCR-ABL oncoprotein. Although the ABL kinase inhibitor (imatinib) has proven to be very effective in achieving high remission rates and improving prognosis, up to 33% of CML patients still cannot achieve an optimal response. Here, we used CRISPR/Cas9 to specifically target the BCR-ABL junction region in K562 cells, resulting in the inhibition of cancer cell growth and oncogenesis. Due to the variety of BCR-ABL junctions in CML patients, we utilized gene editing of the human ABL gene for clinical applications. Using the ABL gene-edited virus in K562 cells, we detected 41.2% indels in ABL sgRNA_2-infected cells. The ABL-edited cells reveled significant suppression of BCR-ABL protein expression and downstream signals, inhibiting cell growth and increasing cell apoptosis. Next, we introduced the ABL gene-edited virus into a systemic K562 leukemia xenograft mouse model, and bioluminescence imaging of the mice showed a significant reduction in the leukemia cell population in ABL-targeted mice, compared to the scramble sgRNA virus-injected mice. In CML cells from clinical samples, infection with the ABL gene-edited virus resulted in more than 30.9% indels and significant cancer cell death. Notably, no off-target effects or bone marrow cell suppression was found using the ABL gene-edited virus, ensuring both user safety and treatment efficacy. This study demonstrated the critical role of the ABL gene in maintaining CML cell survival and tumorigenicity in vitro and in vivo. ABL gene editing-based therapy might provide a potential strategy for imatinib-insensitive or resistant CML patients.

Inducible nitric oxide synthase inhibition influenced granuloma formation with suppressed collagen expression in myositis caused by Toxocara canis in mice.

The role of nitric oxide (NO) in granuloma pathology is largely unclear to date. We investigated the role of NO in fibrotic granuloma development in the musculature of mice infected with Toxocara canis from 1 day (dpi) to 8 weeks post-infection (wpi) using the NO synthase (NOS) inhibitors, L-NIL (l-N6-1-iminoethyl lysine). In infected mice, elevated serum NO concentrations were seen at 1 dpi (204.1 +/- 0.2 microM) and 1 wpi (145.1 +/- 0.2 microM); it declined drastically from 4 wpi onwards (57.0 +/- 0.1 microM). In L-NIL-treated mice, the NO concentration was drastically reduced from 15% during 1 wpi; thereafter, it was restored to almost half that in infected mice. Inducible NOS expression was enhanced in infected and L-NIL-treated mice at 4 wpi but declined at 8 wpi as assessed by immunohistochemistry. L-NIL treatment resulted in large, irregularly shaped granulomas with suppressed collagen contents at 4 wpi but not at 8 wpi. The suppressed collagen contents might have been related to decreased serum NO and Th2-type cytokine of interleukin-4 but not Th1-type cytokine of interferon-gamma expression.

Aberrant activation of the TNF-alpha system and production of Fas and scavenger receptors on monocytes in patients with end-stage renal disease.

Ten patients with nondialyzed chronic renal failure (CRF), 14 receiving continuous ambulatory peritoneal dialysis (CAPD), 16 receiving hemodialysis (HD), and 10 normal controls (NC), were evaluated. Levels of Fas antigen (CD95), scavenger receptors (CD36 and CD68), and tumor necrosis factor-receptor 2 (CD120b) on monocytes were measured using flow cytometry. All patients showed lymphocytopenia, and monocyte counts were decreased in those with CRF. Fas levels were higher in patients receiving HD than the others, and were higher in the CRF and CAPD groups than in controls. CD120b levels were similar to those of Fas. Monocyte CD36 levels in the dialysis groups were significantly higher than in the CRF and NC groups. CD68 was also significantly elevated in HD patients. Fas levels were positively correlated with those of CD120b and CD68. The patient groups showed higher levels of apoptotic markers and scavenger receptors, combined with activation of the TNF-alpha system, especially in patients receiving HD.