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Biological rational for sequential targeting of Bruton tyrosine kinase and Bcl-2 to overcome CD40-induced ABT-199 resistance in mantle cell lymphoma.

Chiron D, Dousset C, Brosseau C, Touzeau C, Maïga S, Moreau P, Pellat-Deceunynck C, Le Gouill S, Amiot M - Oncotarget (2015)

Bottom Line: We show here for two patients undergoing ibrutinib therapy that mobilized MCL cells are highly sensitive to ABT-199.These results provide evidence that in situ ABT-199 resistance can be overcome when MCL cells escape from the lymph nodes.Altogether, our data support the clinical application of ABT-199 therapy both as a single agent and in sequential combination with BTK inhibitors.

View Article: PubMed Central - PubMed

Affiliation: INSERM, UMR892 - CNRS, UMR 6299, Université de Nantes, France.

ABSTRACT
The aggressive biological behavior of mantle cell lymphoma (MCL) and its short response to current treatment highlight a great need for better rational therapy. Herein, we investigate the ability of ABT-199, the Bcl-2-selective BH3 mimetic, to kill MCL cells. Among MCL cell lines tested (n = 8), only three were sensitive (LD50 < 200 nM). In contrast, all primary MCL samples tested (n = 11) were highly sensitive to ABT-199 (LD50 < 10 nM). Mcl-1 and Bcl-xL both confer resistance to ABT-199-specific killing and BCL2/(BCLXL+MCL1) mRNA ratio is a strong predictor of sensitivity. By mimicking the microenvironment through CD40 stimulation, we show that ABT-199 sensitivity is impaired through activation of NF-kB pathway and Bcl-x(L) up-regulation. We further demonstrate that resistance is rapidly lost when MCL cells detach from CD40L-expressing fibroblasts. It has been reported that ibrutinib induces lymphocytosis in vivo holding off malignant cells from their protective microenvironment. We show here for two patients undergoing ibrutinib therapy that mobilized MCL cells are highly sensitive to ABT-199. These results provide evidence that in situ ABT-199 resistance can be overcome when MCL cells escape from the lymph nodes. Altogether, our data support the clinical application of ABT-199 therapy both as a single agent and in sequential combination with BTK inhibitors.

No MeSH data available.


Related in: MedlinePlus

CD40 stimulation resulted in strong resistance to ABT-199(A) MCL cell lines were cultured alone or on either parental fibroblast L or CD40L-expressing fibroblasts L (L-40L) for 24 hours before being exposed to ABT-199. Cell death was assessed in triplicate by using Apo-2.7 staining. (B) Primary MCL cells were cultured alone or on either L or L-40L cells for 24 hours then exposed to 25 nM ABT-199 for 48 hours. Apoptosis was determined by Apo2.7 and CD19 staining.
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Figure 2: CD40 stimulation resulted in strong resistance to ABT-199(A) MCL cell lines were cultured alone or on either parental fibroblast L or CD40L-expressing fibroblasts L (L-40L) for 24 hours before being exposed to ABT-199. Cell death was assessed in triplicate by using Apo-2.7 staining. (B) Primary MCL cells were cultured alone or on either L or L-40L cells for 24 hours then exposed to 25 nM ABT-199 for 48 hours. Apoptosis was determined by Apo2.7 and CD19 staining.

Mentions: Because MCL cells mainly reside in lymph nodes we next asked whether microenvironment interactions could impact their sensitivity to ABT-199. In order to mimic the lymph node microenvironment where CD40-CD40L interaction takes place, ABT-199 sensitive MCL cell lines (MINO and MAVER-1) were cultured on CD40L-expressing fibroblast L cells (L-40L). Co-culture with L-40L dramatically reduces their sensitivity to ABT-199 while co-culture with parental fibroblast L cells failed to induce significant resistance (Fig. 2A). Of note, primary MCL cells from patients were also significantly more resistant to ABT-199 when cultured on L-40L with 25 nM of ABT-199 (n = 6; p < 0.001) (Fig. 2B). By contrast, culture of MINO cells with conditioned medium from L-40L culture or with bone marrow stromal cells (HS5) failed to reduce ABT-199 sensitivity (data not shown). These results indicate that the CD40 pathway is directly involved in the resistance to ABT-199 in both MCL cell lines and primary cells.


Biological rational for sequential targeting of Bruton tyrosine kinase and Bcl-2 to overcome CD40-induced ABT-199 resistance in mantle cell lymphoma.

Chiron D, Dousset C, Brosseau C, Touzeau C, Maïga S, Moreau P, Pellat-Deceunynck C, Le Gouill S, Amiot M - Oncotarget (2015)

CD40 stimulation resulted in strong resistance to ABT-199(A) MCL cell lines were cultured alone or on either parental fibroblast L or CD40L-expressing fibroblasts L (L-40L) for 24 hours before being exposed to ABT-199. Cell death was assessed in triplicate by using Apo-2.7 staining. (B) Primary MCL cells were cultured alone or on either L or L-40L cells for 24 hours then exposed to 25 nM ABT-199 for 48 hours. Apoptosis was determined by Apo2.7 and CD19 staining.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4496181&req=5

Figure 2: CD40 stimulation resulted in strong resistance to ABT-199(A) MCL cell lines were cultured alone or on either parental fibroblast L or CD40L-expressing fibroblasts L (L-40L) for 24 hours before being exposed to ABT-199. Cell death was assessed in triplicate by using Apo-2.7 staining. (B) Primary MCL cells were cultured alone or on either L or L-40L cells for 24 hours then exposed to 25 nM ABT-199 for 48 hours. Apoptosis was determined by Apo2.7 and CD19 staining.
Mentions: Because MCL cells mainly reside in lymph nodes we next asked whether microenvironment interactions could impact their sensitivity to ABT-199. In order to mimic the lymph node microenvironment where CD40-CD40L interaction takes place, ABT-199 sensitive MCL cell lines (MINO and MAVER-1) were cultured on CD40L-expressing fibroblast L cells (L-40L). Co-culture with L-40L dramatically reduces their sensitivity to ABT-199 while co-culture with parental fibroblast L cells failed to induce significant resistance (Fig. 2A). Of note, primary MCL cells from patients were also significantly more resistant to ABT-199 when cultured on L-40L with 25 nM of ABT-199 (n = 6; p < 0.001) (Fig. 2B). By contrast, culture of MINO cells with conditioned medium from L-40L culture or with bone marrow stromal cells (HS5) failed to reduce ABT-199 sensitivity (data not shown). These results indicate that the CD40 pathway is directly involved in the resistance to ABT-199 in both MCL cell lines and primary cells.

Bottom Line: We show here for two patients undergoing ibrutinib therapy that mobilized MCL cells are highly sensitive to ABT-199.These results provide evidence that in situ ABT-199 resistance can be overcome when MCL cells escape from the lymph nodes.Altogether, our data support the clinical application of ABT-199 therapy both as a single agent and in sequential combination with BTK inhibitors.

View Article: PubMed Central - PubMed

Affiliation: INSERM, UMR892 - CNRS, UMR 6299, Université de Nantes, France.

ABSTRACT
The aggressive biological behavior of mantle cell lymphoma (MCL) and its short response to current treatment highlight a great need for better rational therapy. Herein, we investigate the ability of ABT-199, the Bcl-2-selective BH3 mimetic, to kill MCL cells. Among MCL cell lines tested (n = 8), only three were sensitive (LD50 < 200 nM). In contrast, all primary MCL samples tested (n = 11) were highly sensitive to ABT-199 (LD50 < 10 nM). Mcl-1 and Bcl-xL both confer resistance to ABT-199-specific killing and BCL2/(BCLXL+MCL1) mRNA ratio is a strong predictor of sensitivity. By mimicking the microenvironment through CD40 stimulation, we show that ABT-199 sensitivity is impaired through activation of NF-kB pathway and Bcl-x(L) up-regulation. We further demonstrate that resistance is rapidly lost when MCL cells detach from CD40L-expressing fibroblasts. It has been reported that ibrutinib induces lymphocytosis in vivo holding off malignant cells from their protective microenvironment. We show here for two patients undergoing ibrutinib therapy that mobilized MCL cells are highly sensitive to ABT-199. These results provide evidence that in situ ABT-199 resistance can be overcome when MCL cells escape from the lymph nodes. Altogether, our data support the clinical application of ABT-199 therapy both as a single agent and in sequential combination with BTK inhibitors.

No MeSH data available.


Related in: MedlinePlus