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Mapping of apoptin-interaction with BCR-ABL1, and development of apoptin-based targeted therapy.

Jangamreddy JR, Panigrahi S, Lotfi K, Yadav M, Maddika S, Tripathi AK, Sanyal S, Łos MJ - Oncotarget (2014)

Bottom Line: Majority of chronic myeloid leukemia patients experience an adequate therapeutic effect from imatinib however, 26-37% of patients discontinue imatinib therapy due to a suboptimal response or intolerance.The synthetic apoptin is able to inhibit cell proliferation in murine (32Dp210), human cell line (K562), and ex vivo in both imatinib-resistant and imatinib sensitive CML patient samples.The apoptin based single or combination therapy may be an additional option in CML treatment and eventually be feasible as curative therapy.

View Article: PubMed Central - PubMed

Affiliation: Dept. Clinical & Experimental Medicine, Integrative Regenerative Med. Center (IGEN), Linköping University, Sweden. Authors contributed equally.

ABSTRACT
Majority of chronic myeloid leukemia patients experience an adequate therapeutic effect from imatinib however, 26-37% of patients discontinue imatinib therapy due to a suboptimal response or intolerance. Here we investigated derivatives of apoptin, a chicken anemia viral protein with selective toxicity towards cancer cells, which can be directed towards inhibiting multiple hyperactive kinases including BCR-ABL1. Our earlier studies revealed that a proline-rich segment of apoptin interacts with the SH3 domain of fusion protein BCR-ABL1 (p210) and acts as a negative regulator of BCR-ABL1 kinase and its downstream targets. In this study we show for the first time, the therapeutic potential of apoptin-derived decapeptide for the treatment of CML by establishing the minimal region of apoptin interaction domain with BCR-ABL1. We further show that the apoptin decapeptide is able to inhibit BCR-ABL1 down stream target c-Myc with a comparable efficacy to full-length apoptin and Imatinib. The synthetic apoptin is able to inhibit cell proliferation in murine (32Dp210), human cell line (K562), and ex vivo in both imatinib-resistant and imatinib sensitive CML patient samples. The apoptin based single or combination therapy may be an additional option in CML treatment and eventually be feasible as curative therapy.

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Related in: MedlinePlus

Apoptin interacts with the SH3-domain of Abl – confirmation of apoptin's interaction with BCR-ABL1(a) TransSignal SH3 Domain Array1 interaction of apoptin and SH3 domains of Abl (D 3, 4); (b) Production of recombinant GST conjugated apoptin. (c) Akt, Apoptin & Bcr-Abl Interaction: Class lb SH3 ligand specifically ‘pulls down’ its corresponding protein-protein interaction domains.
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Figure 2: Apoptin interacts with the SH3-domain of Abl – confirmation of apoptin's interaction with BCR-ABL1(a) TransSignal SH3 Domain Array1 interaction of apoptin and SH3 domains of Abl (D 3, 4); (b) Production of recombinant GST conjugated apoptin. (c) Akt, Apoptin & Bcr-Abl Interaction: Class lb SH3 ligand specifically ‘pulls down’ its corresponding protein-protein interaction domains.

Mentions: To investigate possible interactions of apoptin with the SH3 domains of a series of proteins we first performed a protein array-based study. Several well-characterized SH3 domains were previously identified as the potential sites critical to ligand binding on the basis of alignment with their structures [20]. We performed a high stringency SH3 domain interaction array screening, which indicated that apoptin strongly interacts with the SH3 domain of some proteins including Abl (Fig. 2a). The above observation was further confirmed by GST-apoptin and BCR-ABL1p210 ‘pull-down assay’ using both BCR-ABL1-positive (32Dp210), and -negative (32DDSMZ) cell lines (Fig. 2b, 2c) where full length BCR-ABL1p210 with intact SH3 domain showed interaction with GST-apoptin and were ‘pulled-down’ by glutathione sepharose beads. Interestingly when the same blot was incubated with a second primary antibody against Akt, a band positively correlating with the molecular weight of Akt was identified in the GST-apoptin BCR-ABL1 pull-down product indicating a co-reactivity (Fig. 2c).


Mapping of apoptin-interaction with BCR-ABL1, and development of apoptin-based targeted therapy.

Jangamreddy JR, Panigrahi S, Lotfi K, Yadav M, Maddika S, Tripathi AK, Sanyal S, Łos MJ - Oncotarget (2014)

Apoptin interacts with the SH3-domain of Abl – confirmation of apoptin's interaction with BCR-ABL1(a) TransSignal SH3 Domain Array1 interaction of apoptin and SH3 domains of Abl (D 3, 4); (b) Production of recombinant GST conjugated apoptin. (c) Akt, Apoptin & Bcr-Abl Interaction: Class lb SH3 ligand specifically ‘pulls down’ its corresponding protein-protein interaction domains.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4196195&req=5

Figure 2: Apoptin interacts with the SH3-domain of Abl – confirmation of apoptin's interaction with BCR-ABL1(a) TransSignal SH3 Domain Array1 interaction of apoptin and SH3 domains of Abl (D 3, 4); (b) Production of recombinant GST conjugated apoptin. (c) Akt, Apoptin & Bcr-Abl Interaction: Class lb SH3 ligand specifically ‘pulls down’ its corresponding protein-protein interaction domains.
Mentions: To investigate possible interactions of apoptin with the SH3 domains of a series of proteins we first performed a protein array-based study. Several well-characterized SH3 domains were previously identified as the potential sites critical to ligand binding on the basis of alignment with their structures [20]. We performed a high stringency SH3 domain interaction array screening, which indicated that apoptin strongly interacts with the SH3 domain of some proteins including Abl (Fig. 2a). The above observation was further confirmed by GST-apoptin and BCR-ABL1p210 ‘pull-down assay’ using both BCR-ABL1-positive (32Dp210), and -negative (32DDSMZ) cell lines (Fig. 2b, 2c) where full length BCR-ABL1p210 with intact SH3 domain showed interaction with GST-apoptin and were ‘pulled-down’ by glutathione sepharose beads. Interestingly when the same blot was incubated with a second primary antibody against Akt, a band positively correlating with the molecular weight of Akt was identified in the GST-apoptin BCR-ABL1 pull-down product indicating a co-reactivity (Fig. 2c).

Bottom Line: Majority of chronic myeloid leukemia patients experience an adequate therapeutic effect from imatinib however, 26-37% of patients discontinue imatinib therapy due to a suboptimal response or intolerance.The synthetic apoptin is able to inhibit cell proliferation in murine (32Dp210), human cell line (K562), and ex vivo in both imatinib-resistant and imatinib sensitive CML patient samples.The apoptin based single or combination therapy may be an additional option in CML treatment and eventually be feasible as curative therapy.

View Article: PubMed Central - PubMed

Affiliation: Dept. Clinical & Experimental Medicine, Integrative Regenerative Med. Center (IGEN), Linköping University, Sweden. Authors contributed equally.

ABSTRACT
Majority of chronic myeloid leukemia patients experience an adequate therapeutic effect from imatinib however, 26-37% of patients discontinue imatinib therapy due to a suboptimal response or intolerance. Here we investigated derivatives of apoptin, a chicken anemia viral protein with selective toxicity towards cancer cells, which can be directed towards inhibiting multiple hyperactive kinases including BCR-ABL1. Our earlier studies revealed that a proline-rich segment of apoptin interacts with the SH3 domain of fusion protein BCR-ABL1 (p210) and acts as a negative regulator of BCR-ABL1 kinase and its downstream targets. In this study we show for the first time, the therapeutic potential of apoptin-derived decapeptide for the treatment of CML by establishing the minimal region of apoptin interaction domain with BCR-ABL1. We further show that the apoptin decapeptide is able to inhibit BCR-ABL1 down stream target c-Myc with a comparable efficacy to full-length apoptin and Imatinib. The synthetic apoptin is able to inhibit cell proliferation in murine (32Dp210), human cell line (K562), and ex vivo in both imatinib-resistant and imatinib sensitive CML patient samples. The apoptin based single or combination therapy may be an additional option in CML treatment and eventually be feasible as curative therapy.

Show MeSH
Related in: MedlinePlus