ONC201 induces cell death in pediatric non-Hodgkin's lymphoma cells

Figures & data

Figure 1. ONC201 induces a dose-dependent reduction in the cell viability of human lymphoma cell lines. Cell viability assays with ONC201 for 72 hours treatment.

Figure 2. ONC201 induces caspase-dependent apoptosis in human lymphoma cell lines. (A) Sub-G1 DNA content analysis lymphoma cell lines treated with ONC201 at 0.625, 1.25, 2.5, 5 and 10 μM for 72 hours (n = 3). *P < 0.05; **P < 0.005. (B) Sub-G1 DNA content analysis of lymphoma cell lines in the presence or absence of the pan-caspase inhibitor zVAD-fmk (CI) and/or ONC201 for 72 hours.

Figure 3. ONC201 induces the TRAIL pathway in human lymphoma cell lines. (A) Dose-response curve of BJAB cells to recombinant TRAIL or ONC201 at 72 hours post-treatment (n = 3). (B) Fold TRAIL expression of lymphoma cell lines at 60 hours post treatment with ONC201 (n = 3). (C) Correlation of surface TRAIL expression by flow cytometry with sub-G1 DNA content of Ramos, Karpas299, and UPN2 lymphoma cells treated with several doses of ONC201 (0.625, 1.25, 2.5, 5, and 10 μM, n = 3). The Pearson correlation coefficient “r” was 0.9499 with 95% confidence interval of 0.8526 to 0.9836 and a P value of <0.0001. (D) Reduction of cell death by co-incubation with RIK2, a TRAIL-sequestering antibody in Karpas299 cells with 72 hour treatment with ONC201 (n = 2).

Figure 4. ONC201-induced cytotoxicity is enhanced in combination with pediatric NHL chemotherapy. (A) Cell viability assays of Ramos cells following 72 hour treatment with various doses of ONC201 in combination with increasing doses of NHL chemotherapies. 100% cell viability (100%) is represented as darkest green and lowest cell viability (approaching zero) is represented as darkest red. ONC201 doses used were 0.093, 0.1875, 0.375, 0.75, 1.5 μM and n = 2. (B) Cell viability assays of Karpas299 cells following 72 hour treatment with various doses of ONC201 (0.156, 0.3125, 0.625,1.25, 2.5 μM) in combination with increasing doses of cytarabine (n = 2).

Table 1. Combination indices for ONC201 in combination with cytarabine

			Cytarabine(nM)
Karpas299			31.25	62.5	125	250	500	1000	2000
	ONC201 (uM)	0.3125	0.55	0.76	0.41	0.38	0.40	1.03	1.01
		0.625	0.54	0.64	0.46	0.50	0.46	1.12	1.01
		1.25	0.58	0.79	0.57	0.57	0.92	1.25	1.03
		2.5	0.70	0.64	0.66	0.72	0.83	1.10	1.13

Combination indices obtained for Karpas299 cells at 72H post combination treatment with increasing doses of ONC201 combined with increasing doses of cytarabine confirm synergistic cytotoxicity.