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RNA G-quadruplexes cause eIF4A-dependent oncogene translation in cancer.

Wolfe AL, Singh K, Zhong Y, Drewe P, Rajasekhar VK, Sanghvi VR, Mavrakis KJ, Jiang M, Roderick JE, Van der Meulen J, Schatz JH, Rodrigo CM, Zhao C, Rondou P, de Stanchina E, Teruya-Feldstein J, Kelliher MA, Speleman F, Porco JA, Pelletier J, Rätsch G, Wendel HG - Nature (2014)

Bottom Line: Accordingly, inhibition of eIF4A with silvestrol has powerful therapeutic effects against murine and human leukaemic cells in vitro and in vivo.Notably, among the most eIF4A-dependent and silvestrol-sensitive transcripts are a number of oncogenes, superenhancer-associated transcription factors, and epigenetic regulators.Hence, the 5' UTRs of select cancer genes harbour a targetable requirement for the eIF4A RNA helicase.

View Article: PubMed Central - PubMed

Affiliation: 1] Cancer Biology and Genetics, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA [2] Weill Cornell Graduate School of Medical Sciences, New York, New York 10065, USA [3].

ABSTRACT
The translational control of oncoprotein expression is implicated in many cancers. Here we report an eIF4A RNA helicase-dependent mechanism of translational control that contributes to oncogenesis and underlies the anticancer effects of silvestrol and related compounds. For example, eIF4A promotes T-cell acute lymphoblastic leukaemia development in vivo and is required for leukaemia maintenance. Accordingly, inhibition of eIF4A with silvestrol has powerful therapeutic effects against murine and human leukaemic cells in vitro and in vivo. We use transcriptome-scale ribosome footprinting to identify the hallmarks of eIF4A-dependent transcripts. These include 5' untranslated region (UTR) sequences such as the 12-nucleotide guanine quartet (CGG)4 motif that can form RNA G-quadruplex structures. Notably, among the most eIF4A-dependent and silvestrol-sensitive transcripts are a number of oncogenes, superenhancer-associated transcription factors, and epigenetic regulators. Hence, the 5' UTRs of select cancer genes harbour a targetable requirement for the eIF4A RNA helicase.

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Related in: MedlinePlus

Silvestrol has single-agent activity against T-ALLa) Reporter system with capped renilla luciferase (red) and firefly luciferase under the HCV IRES (black); (below) Relative levels of renilla luciferase (red) and firefly (black) luciferase upon vehicle (DMSO), Silvestrol, or (±)-CR-31-B. Mean/SD, n = 3 biological replicates; b) Viability of primary patient T-ALL samples treated with Silvestrol (48 h; mean/SD of 4 replicates; c) Tumour size of KOPT-K1 xenografts treated with (±)-CR-31-B (0.2 mg/kg) or vehicle, mean/SD of 5 tumors; d) Immunohistochemical analysis of (±)-CR-31-B treated KOPT-K1 tumours; e) Diagram of drug targets; f) Lysates of KOPT-K1 cells treated with vehicle (Veh), Rapamycin (Rapa: 25 nM), (±)-CR-31-B (CR: 25 nM), or Silvestrol (Silv: 25 nM) for 48 hours and probed as indicated.
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Figure 2: Silvestrol has single-agent activity against T-ALLa) Reporter system with capped renilla luciferase (red) and firefly luciferase under the HCV IRES (black); (below) Relative levels of renilla luciferase (red) and firefly (black) luciferase upon vehicle (DMSO), Silvestrol, or (±)-CR-31-B. Mean/SD, n = 3 biological replicates; b) Viability of primary patient T-ALL samples treated with Silvestrol (48 h; mean/SD of 4 replicates; c) Tumour size of KOPT-K1 xenografts treated with (±)-CR-31-B (0.2 mg/kg) or vehicle, mean/SD of 5 tumors; d) Immunohistochemical analysis of (±)-CR-31-B treated KOPT-K1 tumours; e) Diagram of drug targets; f) Lysates of KOPT-K1 cells treated with vehicle (Veh), Rapamycin (Rapa: 25 nM), (±)-CR-31-B (CR: 25 nM), or Silvestrol (Silv: 25 nM) for 48 hours and probed as indicated.

Mentions: Silvestrol and a synthetic analogue (±)-CR-31-B (CR) inhibit eIF4A1/211,22. A reporter assay confirms that both drugs preferentially block cap-dependent translation of renilla luciferase compared to firefly luciferase expressed from the HCV IRES (Figure 2a, Extended Data Fig. 2a). Silvestrol induces cell death in primary human T-ALL samples, cell lines, and murine T-ALLs at nanomolar IC50s (Figure 2b, Extended Data Fig. 2b/c). In vivo Silvestrol is effective against murine or xenografted T-ALLs (Figure 2c, Extended Data Fig. 2d–f). In KOPT-K1 tumour-bearing (~1 cm3) NOD/SCID mice, treatment with Silvestrol (0.5 mg/kg, i.p., d 0–6, n = 7, p < 0.001) or (±)-CR-31-B (0.2 mg/kg, i.p., d 0–6, n = 8, p < 0.001) delays tumour growth, and causes apoptosis and cell cycle arrest (Figure 2c/d, Extended Data Fig. 2e/f). Detailed toxicology shows that this treatment is well-tolerated in mice (Extended Data Fig. 3a–j, Suppl. Table 2). Rapamycin induces an S6 kinase-dependent feedback activation of AKT (T308)23, by contrast Silvestrol or (±)-CR-31-B do not trigger this response in KOPT-K1 cells (Figure 2e/f). The result implies that inhibition of eIF4A is effective without effect on S6 kinase.


RNA G-quadruplexes cause eIF4A-dependent oncogene translation in cancer.

Wolfe AL, Singh K, Zhong Y, Drewe P, Rajasekhar VK, Sanghvi VR, Mavrakis KJ, Jiang M, Roderick JE, Van der Meulen J, Schatz JH, Rodrigo CM, Zhao C, Rondou P, de Stanchina E, Teruya-Feldstein J, Kelliher MA, Speleman F, Porco JA, Pelletier J, Rätsch G, Wendel HG - Nature (2014)

Silvestrol has single-agent activity against T-ALLa) Reporter system with capped renilla luciferase (red) and firefly luciferase under the HCV IRES (black); (below) Relative levels of renilla luciferase (red) and firefly (black) luciferase upon vehicle (DMSO), Silvestrol, or (±)-CR-31-B. Mean/SD, n = 3 biological replicates; b) Viability of primary patient T-ALL samples treated with Silvestrol (48 h; mean/SD of 4 replicates; c) Tumour size of KOPT-K1 xenografts treated with (±)-CR-31-B (0.2 mg/kg) or vehicle, mean/SD of 5 tumors; d) Immunohistochemical analysis of (±)-CR-31-B treated KOPT-K1 tumours; e) Diagram of drug targets; f) Lysates of KOPT-K1 cells treated with vehicle (Veh), Rapamycin (Rapa: 25 nM), (±)-CR-31-B (CR: 25 nM), or Silvestrol (Silv: 25 nM) for 48 hours and probed as indicated.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4492470&req=5

Figure 2: Silvestrol has single-agent activity against T-ALLa) Reporter system with capped renilla luciferase (red) and firefly luciferase under the HCV IRES (black); (below) Relative levels of renilla luciferase (red) and firefly (black) luciferase upon vehicle (DMSO), Silvestrol, or (±)-CR-31-B. Mean/SD, n = 3 biological replicates; b) Viability of primary patient T-ALL samples treated with Silvestrol (48 h; mean/SD of 4 replicates; c) Tumour size of KOPT-K1 xenografts treated with (±)-CR-31-B (0.2 mg/kg) or vehicle, mean/SD of 5 tumors; d) Immunohistochemical analysis of (±)-CR-31-B treated KOPT-K1 tumours; e) Diagram of drug targets; f) Lysates of KOPT-K1 cells treated with vehicle (Veh), Rapamycin (Rapa: 25 nM), (±)-CR-31-B (CR: 25 nM), or Silvestrol (Silv: 25 nM) for 48 hours and probed as indicated.
Mentions: Silvestrol and a synthetic analogue (±)-CR-31-B (CR) inhibit eIF4A1/211,22. A reporter assay confirms that both drugs preferentially block cap-dependent translation of renilla luciferase compared to firefly luciferase expressed from the HCV IRES (Figure 2a, Extended Data Fig. 2a). Silvestrol induces cell death in primary human T-ALL samples, cell lines, and murine T-ALLs at nanomolar IC50s (Figure 2b, Extended Data Fig. 2b/c). In vivo Silvestrol is effective against murine or xenografted T-ALLs (Figure 2c, Extended Data Fig. 2d–f). In KOPT-K1 tumour-bearing (~1 cm3) NOD/SCID mice, treatment with Silvestrol (0.5 mg/kg, i.p., d 0–6, n = 7, p < 0.001) or (±)-CR-31-B (0.2 mg/kg, i.p., d 0–6, n = 8, p < 0.001) delays tumour growth, and causes apoptosis and cell cycle arrest (Figure 2c/d, Extended Data Fig. 2e/f). Detailed toxicology shows that this treatment is well-tolerated in mice (Extended Data Fig. 3a–j, Suppl. Table 2). Rapamycin induces an S6 kinase-dependent feedback activation of AKT (T308)23, by contrast Silvestrol or (±)-CR-31-B do not trigger this response in KOPT-K1 cells (Figure 2e/f). The result implies that inhibition of eIF4A is effective without effect on S6 kinase.

Bottom Line: Accordingly, inhibition of eIF4A with silvestrol has powerful therapeutic effects against murine and human leukaemic cells in vitro and in vivo.Notably, among the most eIF4A-dependent and silvestrol-sensitive transcripts are a number of oncogenes, superenhancer-associated transcription factors, and epigenetic regulators.Hence, the 5' UTRs of select cancer genes harbour a targetable requirement for the eIF4A RNA helicase.

View Article: PubMed Central - PubMed

Affiliation: 1] Cancer Biology and Genetics, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA [2] Weill Cornell Graduate School of Medical Sciences, New York, New York 10065, USA [3].

ABSTRACT
The translational control of oncoprotein expression is implicated in many cancers. Here we report an eIF4A RNA helicase-dependent mechanism of translational control that contributes to oncogenesis and underlies the anticancer effects of silvestrol and related compounds. For example, eIF4A promotes T-cell acute lymphoblastic leukaemia development in vivo and is required for leukaemia maintenance. Accordingly, inhibition of eIF4A with silvestrol has powerful therapeutic effects against murine and human leukaemic cells in vitro and in vivo. We use transcriptome-scale ribosome footprinting to identify the hallmarks of eIF4A-dependent transcripts. These include 5' untranslated region (UTR) sequences such as the 12-nucleotide guanine quartet (CGG)4 motif that can form RNA G-quadruplex structures. Notably, among the most eIF4A-dependent and silvestrol-sensitive transcripts are a number of oncogenes, superenhancer-associated transcription factors, and epigenetic regulators. Hence, the 5' UTRs of select cancer genes harbour a targetable requirement for the eIF4A RNA helicase.

Show MeSH
Related in: MedlinePlus