Zotatifin, an eIF4A-Selective Inhibitor, Blocks Tumor Growth in Receptor Tyrosine Kinase Driven Tumors

Oncoprotein expression is controlled at the level of mRNA translation and is regulated by the eukaryotic translation initiation factor 4F (eIF4F) complex. eIF4A, a component of eIF4F, catalyzes the unwinding of secondary structure in the 5'-untranslated region (5'-UTR) of mRNA to facilitate ribosome scanning and translation initiation. Zotatifin (eFT226) is a selective eIF4A inhibitor that increases the affinity between eIF4A and specific polypurine sequence motifs and has been reported to inhibit translation of driver oncogenes in models of lymphoma. Here we report the identification of zotatifin binding motifs in the 5'-UTRs of HER2 and FGFR1/2 Receptor Tyrosine Kinases (RTKs). Dysregulation of HER2 or FGFR1/2 in human cancers leads to activation of the PI3K/AKT and RAS/ERK signaling pathways, thus enhancing eIF4A activity and promoting the translation of select oncogenes that are required for tumor cell growth and survival. In solid tumor models driven by alterations in HER2 or FGFR1/2, downregulation of oncoprotein expression by zotatifin induces sustained pathway-dependent anti-tumor activity resulting in potent inhibition of cell proliferation, induction of apoptosis, and significant in vivo tumor growth inhibition or regression. Sensitivity of RTK-driven tumor models to zotatifin correlated with high basal levels of mTOR activity and elevated translational capacity highlighting the unique circuitry generated by the RTK-driven signaling pathway. This dependency identifies the potential for rational combination strategies aimed at vertical inhibition of the PI3K/AKT/eIF4F pathway. Combination of zotatifin with PI3K or AKT inhibitors was beneficial across RTK-driven cancer models by blocking RTK-driven resistance mechanisms demonstrating the clinical potential of these combination strategies.

TPX-0131, a Potent CNS-penetrant, Next-generation Inhibitor of Wild-type ALK and ALK-resistant Mutations

Since 2011, with the approval of crizotinib and subsequent approval of four additional targeted therapies, anaplastic lymphoma kinase (ALK) inhibitors have become important treatments for a subset of patients with lung cancer. Each generation of ALK inhibitor showed improvements in terms of central nervous system (CNS) penetration and potency against wild-type (WT) ALK, yet a key continued limitation is their susceptibility to resistance from ALK active-site mutations. The solvent front mutation (G1202R) and gatekeeper mutation (L1196M) are major resistance mechanisms to the first two generations of inhibitors while patients treated with the third-generation ALK inhibitor lorlatinib often experience progressive disease with multiple mutations on the same allele (mutations in cis, compound mutations). TPX-0131 is a compact macrocyclic molecule designed to fit within the ATP-binding boundary to inhibit ALK fusion proteins. In cellular assays, TPX-0131 was more potent than all five approved ALK inhibitors against WT ALK and many types of ALK resistance mutations, e.g., G1202R, L1196M, and compound mutations. In biochemical assays, TPX-0131 potently inhibited (IC50 <10 nmol/L) WT ALK and 26 ALK mutants (single and compound mutations). TPX-0131, but not lorlatinib, caused complete tumor regression in ALK (G1202R) and ALK compound mutation-dependent xenograft models. Following repeat oral administration of TPX-0131 to rats, brain levels of TPX-0131 were approximately 66% of those observed in plasma. Taken together, preclinical studies show that TPX-0131 is a CNS-penetrant, next-generation ALK inhibitor that has potency against WT ALK and a spectrum of acquired resistance mutations, especially the G1202R solvent front mutation and compound mutations, for which there are currently no effective therapies.

Abstract 1469: TPX-0131, a potent inhibitor of wild type ALK and a broad spectrum of both single and compound ALK resistance mutations

Three generations of ALK inhibitors are approved for the treatment of ALK+ NSCLC but their efficacy is often limited by ALK resistance mutations. The solvent front mutation G1202R and gatekeeper mutation L1196M are major resistance mechanisms to the first two generations of inhibitors. Patients treated with second generation inhibitors are reported to progress with multiple mutations on separate alleles (mutations in trans). In contrast, 35 - 48% of patients treated with lorlatinib progress with multiple mutations on the same allele (compound mutations, mutations in cis). TPX-0131 is an ALK inhibitor with a compact macrocyclic structure designed to bind completely within the ATP binding boundary and overcome a spectrum of single and compound ALK resistant mutations. TPX-0131 was profiled against previous generations of ALK inhibitors both in vitro and in vivo. In biochemical assays, TPX-0131 potently inhibits (IC50 &lt;10 nM) wild type (WT) ALK and 26 ALK mutations (single and compound). Cell proliferation assays of WT, single mutations, and compound mutations were used to evaluate TPX-0131 relative to previous generations of ALK inhibitions (crizotinib, alectinib, brigatinib, ceritinib, lorlatinib). TPX-0131 is more potent against WT EML4-ALK (IC50 = 0.4 nM) than previous generations of ALK inhibitors (2-fold, lorlatinib; 10 - 30-fold, second generation inhibitors; &gt;100-fold, crizotinib). TPX-0131 potently inhibits EML4-ALK harboring a G1202R solvent front mutation (IC50 = 0.2 nM) which is &gt;100-fold more potent than previous generations of ALK inhibitors. TPX-0131 potently inhibits ALK harboring a gatekeeper mutation (IC50 = 0.5 nM) and is &gt;10-fold more potent than previous generations of ALK inhibitors. TPX-0131 potently inhibits ALK with a L1198F hinge area mutation (IC50 = 0.2 nM) which is 87 - 3000-fold more potent than previous generations of ALK inhibitors. TPX-0131 is the most potent inhibitor against nine EML4-ALK double and triple compound mutations (6 with IC50 &lt; 1 nM, 3 with IC50 1.6 - 14.9 nM). Evaluation of ALK phosphorylation as a pharmacodynamic marker in tumors showed potent ALK inhibition by TPX-0131 that correlated with TPX-0131 exposure. In Ba/F3 cell-derived xenograft tumor models with EML4-ALK mutations, TPX-0131 (2, 5, 10 mg/kg BID) demonstrated robust anti-tumor activity in the G1202R model (64%, 120%, 200% TGI), G1202R/L1198F model (complete regression, all doses), and G1202R/L1196M model (44%, 83% and 200% TGI). In contrast, lorlatinib (5 mg/kg BID) caused 31% TGI in the G1202R/L1198F model and did not have statistically significant TGI in the G1202R/L1196M model. Taken together, TPX-0131 is a next generation ALK inhibitor that has preclinical potency against WT ALK as well as a broad spectrum of acquired resistance mutations, especially compound mutations, which currently lack any effective ALK inhibitor therapy.

Citation Format: Brion W. Murray, Dayong Zhai, Wei Deng, Evan Rogers, Xin Zhang, Jane Ung, Vivian Nguyen, Han Zhang, Maria Barrera, Ana Parra, Jessica Cowell, Dong Lee, Herve Aloysius. TPX-0131, a potent inhibitor of wild type ALK and a broad spectrum of both single and compound ALK resistance mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1469.

Targeting Oncogene mRNA Translation in B-Cell Malignancies with eFT226, a Potent and Selective Inhibitor of eIF4A

The PI3K/AKT/mTOR pathway is often activated in lymphoma through alterations in PI3K, PTEN, and B-cell receptor signaling, leading to dysregulation of eIF4A (through its regulators, eIF4B, eIF4G, and PDCD4) and the eIF4F complex. Activation of eIF4F has a direct role in tumorigenesis due to increased synthesis of oncogenes that are dependent on enhanced eIF4A RNA helicase activity for translation. eFT226, which inhibits translation of specific mRNAs by promoting eIF4A1 binding to 5'-untranslated regions (UTR) containing polypurine and/or G-quadruplex recognition motifs, shows potent antiproliferative activity and significant in vivo efficacy against a panel of diffuse large B-cell lymphoma (DLBCL), and Burkitt lymphoma models with ≤1 mg/kg/week intravenous administration. Evaluation of predictive markers of sensitivity or resistance has shown that activation of eIF4A, mediated by mTOR signaling, correlated with eFT226 sensitivity in in vivo xenograft models. Mutation of PTEN is associated with reduced apoptosis in vitro and diminished efficacy in vivo in response to eFT226. In models evaluated with PTEN loss, AKT was stimulated without a corresponding increase in mTOR activation. AKT activation leads to the degradation of PDCD4, which can alter eIF4F complex formation. The association of eFT226 activity with PTEN/PI3K/mTOR pathway regulation of mRNA translation provides a means to identify patient subsets during clinical development.

Abstract B33: Targeting PI3K/mTOR signaling with potent, selective and orally-available small-molecule inhibitors of eIF4E

Aberrant protein translation plays a role in the pathogenesis of multiple solid tumors and hematologic malignancies. The translation initiation factor eIF4E is essential for the translation of m7G-capped mRNA and is a key point of convergence for several signaling pathways, such as PI3K/mTOR and MAPK, which are intimately involved in tumor cell growth and survival. As such, eIF4E has generated intense interest as a target for anticancer drug discovery. We have designed a series of potent, selective, and orally available m7G cap-competitive inhibitors of eIF4E (eFT-4Ei) with favorable drug-like properties. These inhibitors bind free eIF4E, eIF4E-4EBP and eIF4E-eIF4F complexes within tumor cells. Ribosomal profiling of eIF4E inhibitor-treated tumor cells has identified a subset of translationally regulated target genes that overlap with mTORC1/2 regulated genes, but also include a larger set of unique translationally regulated target mRNAs that are enriched for 5'-TOP, PRTE and CERT sequence elements in their 5'-untranslated regions. eIF4E inhibition results in potent antiproliferative activity and induction of apoptosis in a subset of tumor cell lines. Consistent with this observation, our eIF4E inhibitors show some similarities, yet several important differences from existing mTORC1 or mTORC1/2 dual inhibitors in both cellular and physiologic assays. Finally, significant antitumor efficacy was observed with eIF4E inhibition in both solid tumor and hematologic xenografts in vivo. Taken together, these results highlight the potential of targeting eIF4E as a novel and differentiated therapeutic strategy to treat cancer.

Citation Format: Gregory S. Parker, Ivy N.J. Hung, Jocelyn Staunton, Maria Barrera, Eric Sung, Ana Parra, Craig R. Stumpf, Joan Chen, Peggy A. Thompson, Andreas Nevarez, Christopher J. Wegerski, Jeff Clarine, Samuel Sperry, Alan Xiang, Christian Nilewski, Garrick K. Packard, Kaveri Urklalan, Takasuke Mukaiyama, Theo Michels, Justin T. Ernst, Paul A. Sprengeler, Siegfried H. Reich, Gary G. Chiang, Kevin R. Webster. Targeting PI3K/mTOR signaling with potent, selective and orally-available small-molecule inhibitors of eIF4E [abstract]. In: Proceedings of the AACR Special Conference on Targeting PI3K/mTOR Signaling; 2018 Nov 30-Dec 8; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Res 2020;18(10_Suppl):Abstract nr B33.

Type 2 diabetes progression: A regulatory network approach

In order to elucidate central elements underlying type 2 diabetes, we constructed a regulatory network model involving 37 components (molecules, receptors, processes, etc.) associated to signaling pathways of pancreatic beta-cells. In a first approximation, the network topology was described by Boolean rules whose interacting dynamics predicted stationary patterns broadly classified as health, metabolic syndrome, and diabetes stages. A subsequent approximation based on a continuous logic analysis allowed us to characterize the progression of the disease as transitions between these states associated to alterations of cell homeostasis due to exhaustion or exacerbation of specific regulatory signals. The method allowed the identification of key transcription factors involved in metabolic stress as essential for the progression of the disease. Integration of the present analysis with existent mathematical models designed to yield accurate account of experimental data in human or animal essays leads to reliable predictions for beta-cell mass, insulinemia, glycemia, and glycosylated hemoglobin in diabetic fatty rats.

Abstract 1955: Inhibition of eIF4A by eFT226 blocks KRAS mutant tumor growth

Mutations in KRAS are among the most common oncogenic lesions across a variety of human cancers. Activation of KRAS directs signaling via the MAPK and PI3K pathways to promote tumor growth. One outcome of enhanced KRAS signaling is the induction of mRNA translation by eIF4A, eIF4E, and eIF4G, which together comprise the eIF4F complex. eIF4A is an RNA helicase that functions to unwind elements in the 5'-untranslated region (UTR) of mRNAs to facilitate scanning of the 40S ribosomal subunit. eFT226 is a highly potent and selective inhibitor of eIF4A that functions by forming a ternary complex between eIF4A, eFT226 and specific polypurine motifs in the 5'-UTR of select mRNAs, thus blocking ribosome scanning and inhibiting mRNA translation. This polypurine sequence motif is highly enriched in the 5'-UTR of eFT226 target genes, many of which are known proto-oncogenes. Translational profiling revealed KRAS to be a target of eFT226 and 5'-UTR sequence analysis of KRAS mRNA identified the polypurine regulatory motif, which imparts sensitivity to eFT226 mediated inhibition of translation. In cell-based reporter assays used to monitor translation, mutation of the KRAS 5'-UTR polypurine motifs resulted in a 10-fold decrease in sensitivity to eFT226 relative to the wild-type sequence. In a cell panel screen for in vitro apoptosis induction by eFT226, the most sensitive models were enriched for cell lines driven by KRAS mutations. Consistent with these results, treatment with eFT226 decreased KRAS protein levels, repressed downstream MAPK signaling, inhibited cell proliferation, and induced apoptosis in a collection of non-small cell lung, colorectal and pancreatic KRAS mutant cancer cell lines. The ability of eFT226 to block tumor cell growth and induce apoptosis is independent of the specific KRAS mutation present (e.g. G12C/V, G13D, Q61H/L) suggesting that eFT226 could be broadly efficacious in treating tumors with activating KRAS mutations. Treatment of KRAS mutant solid tumor xenografts with eFT226 as a monotherapy significantly inhibited tumor growth. Together, these results highlight the ability of eFT226 to inhibit growth and promote apoptosis in KRAS mutant tumors and support the clinical development of eFT226 in KRAS driven tumors. A clinical trial evaluating eFT226 in patients with solid tumor malignancies has initiated.

Citation Format: Craig R. Stumpf, Vikas K. Goel, Joan Chen, Jocelyn Staunton, Emily M. Santori, Maria Barrera, Haleigh Howard, Kevin R. Webster, Gary G. Chiang, Peggy A. Thompson. Inhibition of eIF4A by eFT226 blocks KRAS mutant tumor growth [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1955.

Abstract 3399: Preclinical evaluation of eFT226, a potent and selective eIF4A inhibitor with anti-tumor activity in FGFR1,2 and HER2 driven cancers

Mutations or amplifications affecting receptor tyrosine kinases (RTKs) activate the RAS/MAPK and PI3K/AKT signaling pathways thereby promoting cancer cell proliferation and survival. Oncoprotein expression is tightly controlled at the level of mRNA translation and is regulated by the eukaryotic translation initiation factor 4F (eIF4F) complex consisting of eIF4A, eIF4E, and eIF4G. eIF4A functions to catalyze the unwinding of secondary structure in the 5'-untranslated region (5'-UTR) of mRNA facilitating ribosome scanning and translation initiation. The activation of oncogenic signaling pathways, including RAS and PI3K, facilitate formation of eIF4F and enhance eIF4A activity promoting the translation of oncogenes with highly structured 5'-UTRs that are required for tumor cell proliferation, survival and metastasis. eFT226 is a selective eIF4A inhibitor that converts eIF4A into a sequence specific translational repressor by increasing the affinity between eIF4A and 5'-UTR polypurine motifs leading to selective downregulation of mRNA translation. The polypurine element is highly enriched in the 5'-UTR of eFT226 target genes, many of which are known oncogenic drivers, including FGFR1,2 and HER2, enabling eFT226 to selectively inhibit dysregulated oncogene expression. Formation of a ternary complex [eIF4A-eFT226-mRNA] blocks ribosome scanning along the 5'-UTR leading to dose dependent inhibition of RTK protein expression. The 5'-UTR sequence dependency of eFT226 translational inhibition was evaluated in cell-based reporter assays demonstrating 10-45-fold greater sensitivity for reporter constructs containing an RTK 5'-UTR compared to a control. In solid tumor cell lines driven by alterations in FGFR1, FGFR2 or HER2, downregulation of RTK expression by eFT226 resulted in decreased MAPK and AKT signaling, potent inhibition of cell proliferation and an induction of apoptosis suggesting that eFT226 could be effective in treating tumor types dependent on these oncogenic drivers. Solid tumor xenograft models harboring FGFR1,2 or HER2 amplifications treated with eFT226 resulted in significant in vivo tumor growth inhibition and regression at well tolerated doses in breast, non-small cell lung and colorectal cancer models. Treatment with eFT226 also decreased RTK protein levels supporting the potential to use these eFT226 target genes as pharmacodynamic markers of target engagement. Further evaluation of predictive markers of sensitivity or resistance showed that RTK tumor models with mTOR mediated activation of eIF4A are most sensitive to eFT226. The association of eFT226 activity in RTK tumor models with mTOR pathway activation provides a means to further enrich for sensitive patient subsets during clinical development. Clinical trials with eFT226 in patients with solid tumor malignancies have initiated.

Citation Format: Peggy A. Thompson, Nathan P. Young, Adina Gerson-Gurwitz, Boreth Eam, Vikas Goel, Craig R. Stumpf, Joan Chen, Gregory S. Parker, Sarah Fish, Maria Barrera, Eric Sung, Jocelyn Staunton, Gary G. Chiang, Kevin R. Webster. Preclinical evaluation of eFT226, a potent and selective eIF4A inhibitor with anti-tumor activity in FGFR1,2 and HER2 driven cancers [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3399.

Retrospective Analysis of Turkey Arthritis Reovirus Diagnostic Submissions in Minnesota

Turkey arthritis reovirus (TARV) causes tenosynovitis in turkeys, resulting in decreased profits for producers due to the increase in morbidity, mortality, and feed conversion ratio. There is limited information on TARV epidemiology, including the dynamics of diagnostic submissions to veterinary diagnostic laboratories. In this study, we retrospectively analyzed 719 cases of lameness in turkeys submitted to the Minnesota Veterinary Diagnostic Laboratory from March 2010 to May 2018. Almost all submissions were tendon pools, which were tested by virus isolation and/or real-time reverse transcription-polymerase chain reaction. Most of the submissions were from Minnesota. We found 52% of the submitted cases to be positive for TARV. The TARV-positive submissions increased considerably in the last few years. There was no statistical evidence that TARV diagnostic submissions were seasonal, although positive submissions were higher in January, April, July, and December. TARV-positive submissions also increased as flocks aged. In summary, we found that TARV submissions have increased in the last few years, have varied over time, and are correlated with age of the bird. This information is important guidance for conducting more studies to understand TARV infection dynamics.

Abstract B133: eFT226, a first in class inhibitor of eIF4A1, targets FGFR1/2 and HER2 driven cancers

Background: Mutations or amplifications affecting receptor tyrosine kinases (RTKs) activate the RAS/MAPK and PI3K/AKT signaling pathways thereby promoting cancer cell proliferation and survival. Oncoprotein expression is tightly controlled at the level of mRNA translation and is regulated by the eukaryotic translation initiation factor 4F (eIF4F) complex consisting of eIF4A, eIF4E, and eIF4G. eIF4A functions to catalyze the unwinding of secondary structure in the 5’-untranslated region (5’-UTR) of mRNA facilitating ribosome scanning and translation initiation. eFT226 is a first in class inhibitor that converts eIF4A1 into a sequence specific translational repressor. eFT226 increases the affinity between eIF4A1 and polypurine recognition elements in the 5’-UTR leading to selective downregulation of mRNA translation. The polypurine element is highly enriched in the 5’-UTR of eFT226 target genes, many of which are known oncogenic drivers, including FGFR1/2 and HER2, enabling eFT226 to selectively inhibit dysregulated oncogene expression. Methods: 5’-UTR dependency was evaluated using cell-based luciferase reporter assays. Regulation of protein expression was analyzed by western blot analysis. Antitumor activity was assessed in vitro by proliferation and apoptosis assays. For in vivo experiments, athymic nude or NOD/SCID mice were implanted with subcutaneous xenograft models of FGFR1, FGFR2 or HER2 driven tumors and treated with eFT226 administered Q4D IV. Results: eFT226 inhibits the translation of FGFR1, FGFR2 and HER2 through formation of a sequence dependent ternary complex with eIF4A1 and polypurine elements within the 5’-UTR of mRNA [eFT226-eIF4A1-mRNA]. Formation of this ternary complex blocks ribosome scanning along the 5’-UTR leading to dose dependent inhibition of RTK protein expression. Cells transiently transfected with luciferase reporter constructs containing the 5’-UTR of each RTK resulted in 10-45-fold greater sensitivity to inhibition by eFT226 compared to a control 5’-UTR confirming the 5’-UTR dependency. In solid tumor cell lines driven by alterations in FGFR1, FGFR2 or HER2, downregulation of RTK expression by eFT226 resulted in decreased MAPK and AKT signaling, potent inhibition of cell proliferation and an induction of apoptosis suggesting that eFT226 could be effective in treating tumor types dependent on these oncogenic drivers. Solid tumor xenograft models harboring FGFR1/2 or HER2 amplifications treated with eFT226 resulted in significant in vivo tumor growth inhibition and regression at well tolerated doses in breast, non-small cell lung and colorectal cancer models. Treatment with eFT226 also decreased RTK protein levels supporting the potential to use these eFT226 target genes as pharmacodynamic markers of target engagement. Conclusions: eFT226 is efficacious against tumor models with alterations in FGFR1, FGFR2 and HER2 RTKs. The antitumor response observed in preclinical in vivo models driven by RTK amplifications demonstrates the potential for eFT226 in the treatment of solid tumors with FGFR1/2 or HER2 alterations. Furthermore, this data provides a means to select sensitive patient subsets during clinical development. Clinical trials in patients with solid tumor malignancies are planned.

Citation Format: Peggy A Thompson, Nathan P Young, Craig R Stumpf, Boreth Eam, Vikas K Goel, Joan Chen, Sarah Fish, Gregory S Parker, Adina Gerson-Gurwitz, Maria Barrera, Eric Sung, Jocelyn Staunton, Gary G Chiang, Christopher J Wegerski, Samuel Sperry, Kevin R Webster, Siegfried H Reich. eFT226, a first in class inhibitor of eIF4A1, targets FGFR1/2 and HER2 driven cancers [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B133. doi:10.1158/1535-7163.TARG-19-B133

Abstract 1302: Targeting hormone receptor-dependent cancers with potent, selective and orally-available small molecule inhibitors of eIF4E

The PI3K/mTOR pathway is commonly dysregulated in many hormone receptor-dependent tumors and plays a key role in promoting tumor growth and mediating drug resistance. In particular, PI3K and mTORC1/2 inhibitors have been intensively studied in the treatment of hormone receptor-dependent cancers and have shown benefit in some clinical settings. However, issues such as dose-limiting toxicities and emergent resistance limit the broader utility of these inhibitors. The translation initiation factor eIF4E is essential for the translation of m7G-capped mRNA and is a key point of convergence for both the PI3K/mTOR and MAPK signaling pathways. We have designed a series of potent, selective and orally-available m7G cap-competitive inhibitors of eIF4E (eFT-4Ei) with favorable drug-like properties. These inhibitors bind to eIF4E either as its free form or with eIF4E-4EBP and eIF4F complexes within tumor cells and downregulate hormone receptor-dependent signaling. Ribosomal profiling of eIF4E inhibitor-treated tumor cells identified a subset of translationally regulated target genes that overlap with mTORC1/2 regulated genes, but also a unique set of translationally regulated target mRNAs. Consistent with this observation, our eIF4E inhibitors show some similarities yet several important differences from existing mTORC1 or mTORC1/2 dual inhibitors in both cellular and physiological assays. Finally, significant anti-tumor efficacy was observed with eIF4E inhibition in vitro and in vivo. Taken together, these results highlight the potential for targeting eIF4E as a novel therapeutic strategy to treat hormone-receptor dependent cancers.

Citation Format: Gary G. Chiang, Gregory S. Parker, Ivy N. Hung, Vikas K. Goel, Jocelyn Staunton, Maria Barrera, Eric Sung, Ana Parra, Craig R. Stumpf, Joan Chen, Peggy A. Thompson, Andreas Nevarez, Christopher J. Wegerski, Cody Parker, Jeff Clarine, Samuel Sperry, Alan Xiang, Christian Nilewski, Garrick K. Packard, Kaveri Urkalan, Takasuke Mukaiyama, Theo Michels, Justin T. Ernst, Paul A. Sprengeler, Siegfried H. Reich, Kevin R. Webster. Targeting hormone receptor-dependent cancers with potent, selective and orally-available small molecule inhibitors of eIF4E [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1302.

Abstract 2698: eFT226, a potent and selective inhibitor of eIF4A, is efficacious in preclinical models of lymphoma

Dysregulated messenger RNA (mRNA) translation drives the pathogenesis of multiple hematological malignancies. In lymphoma this includes the upregulation of key driver oncogenes and anti-apoptotic proteins (e.g., MYC, CCND1/3, BCL2 and MCL1) that contain a highly structured 5’-untranslated region (UTR) in their mRNA requiring enhanced eIF4A helicase activity for translation. eIF4A is a component of the eIF4F translation initiation complex and catalyzes the ATP-dependent unwinding of RNA duplexes and facilitates 43S ribosome scanning within the 5’-UTR. The activation of oncogenic signaling pathways, including RAS and PI3K, enhance eIF4A activity through phosphorylation of eIF4B, eIF4G and PDCD4 which facilitates formation of eIF4F and full activation of eIF4A. The PI3K/AKT/mTOR pathway is frequently activated in lymphoma, promoting the translation of oncogenes with complex 5’-UTRs that are required for tumor cell proliferation, survival and metastasis.

eFT226 is a potent and sequence selective eIF4A1 inhibitor that promotes eIF4A1 binding to specific 5’-UTR polypurine and/or G-quadraplex recognition motifs leading to a selective block in ribosome mRNA scanning. The sequence dependency of eFT226 translational inhibition was evaluated in cell-based reporter assays demonstrating &gt;100-fold greater sensitivity for reporter constructs containing a polypurine motif in the 5’-UTR (IC50 ~2 nM). Direct binding studies also confirmed the formation of a stable ternary complex with increased drug residence time between eFT226, eIF4A1 and RNA oligonucleotides containing polypurine motifs. The ability of eFT226 to inhibit MYC or MCL1 expression was found to be dependent on the presence of their respective 5’-UTR supporting a translational regulation mechanism dependent on recognition elements within the 5’-UTR.

eFT226 shows potent anti-proliferative activity (GI50 &lt; 15 nM) against a panel of B-cell lymphoma cell lines. Treatment with eFT226 leads to coordinated inhibition of MYC, CCND1/3, BCL2 or MCL1 protein expression resulting in significant anti-tumor activity. eFT226 has good pharmacokinetic properties and exhibits significant in vivo activity across a panel of diffuse large B cell lymphoma (DLBCL), and Burkitt lymphoma tumor models with ≤1 mg/kg/week IV administration. Further evaluation of predictive markers of sensitivity or resistance has shown that tumors with mTOR mediated activation of eIF4A are most sensitive to eFT226. In addition, tumors with PTEN mutations do not exhibit activated eIF4A and are generally resistant to induction of apoptosis by eFT226, resulting in reduced in vivo efficacy. The association of eFT226 activity with PI3K/mTOR pathway activation and mutational status provides a means to identify patient subsets during clinical development. Clinical trials in patients with lymphoma and other malignancies are planned.

Citation Format: Peggy A. Thompson, Boreth Eam, Nathan P. Young, Sarah Fish, Joan Chen, Maria Barrera, Haleigh Howard, Eric Sung, Ana Parra, Jocelyn Staunton, Gary G. Chiang, Christopher J. Wegerski, Andres Nevarez, Jeff Clarine, Samuel Sperry, Alan Xiang, Chinh Tran, Christian Nilewski, Garrick K. Packard, Theodore Michels, Paul A. Sprengeler, Justin T. Ernst, Siegfried H. Reich, Kevin R. Webster. eFT226, a potent and selective inhibitor of eIF4A, is efficacious in preclinical models of lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2698.

Abstract 5546: eFT508, a potent and highly selective inhibitor of MNK1 and MNK2, regulates T-cell differentiation promoting an antitumor immune response

An effective and durable T-cell response is a cornerstone of current immunotherapies. We show that eFT508, a potent, selective inhibitor of MNK1 and MNK2, establishes a regulatory program that promotes multiple steps in the cancer immunity cycle including expansion of memory T cells and prevention of T-cell exhaustion. Using OT-I and OT-II transgenic systems, we show that eFT508 shifts the distribution of T cells towards a CD62LhighCD44high central memory (CM) phenotype in both CD4 and CD8 T cells upon activation with SIINFEKL peptide in vitro without adverse effects on T-cell proliferation, interferon-γ production or cytotoxic function. Similar effects are seen in vivo, where eFT508 treatment also enriches the CM T-cell pool in a SIINFEKL vaccine-induced OT-I adoptive T-cell transfer model, which results in increased persistence as demonstrated by a higher memory-recall T-cell response upon rechallenge. In addition, the CM bias elicited by eFT508 remains dominant when combined with agonists of co-stimulatory molecules, such as 4-1BB, OX-40 and GITR, or checkpoint inhibitors, such as PD-1, PD-L1 and CTLA-4, suggesting that eFT508 can affect the rate of T-cell differentiation in these combinations. eFT508 treatment also reduces the expression of exhaustion markers such as PD-1, LAG3 and TIM3, leading to increased cytotoxic T-cell function. eFT508 is currently under evaluation as a single agent in two phase 1/2 clinical trials for patients with advanced solid tumors and patients with advanced lymphoma. In addition, a phase 2 study evaluating eFT508, alone or in combination with avelumab, a PD-L1 immune checkpoint inhibitor, in microsatellite stable relapsed or refractory CRC patients is ongoing. The preclinical studies presented here provide further evidence that eFT508 may combine well with additional immunotherapies beyond checkpoint blockade.

Citation Format: Rajesh K. Sharma, Vikas K. Goel, Jocelyn Staunton, Maria Barrera, Ana Parra, Eric Sung, Gary G. Chiang, Kevin R. Webster. eFT508, a potent and highly selective inhibitor of MNK1 and MNK2, regulates T-cell differentiation promoting an antitumor immune response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5546.

Laboratorio: Balance hídrico en los anfibios anuros

Los anfibios, y en especial los anuros (sapos y ranas), han sido los animales preferidos para la experimentación desde el comienzo del estudio biológico científico.

Abstract 52: Antitumor activity of entrectinib, a highly potent pan-TRK, ROS1, and ALK inhibitor, in NTRK-fusion positive acute myeloid leukemia

Acute myeloid leukemia (AML) is the most common form of acute leukemia in adults and comprises a heterogeneous group of diseases. A number of recurrent leukemogenic gene mutations or chromosomal rearrangements have been identified and clinically validated in AML. However, nearly 50% of AML patient samples lack any known canonical AML driver mutations. Advances in molecular diagnostics have resulted in the identification of novel and actionable gene mutations or chromosomal rearrangements in a subset of these AML samples. The ETV6-NTRK3 fusion gene is one such rearrangement identified in samples from patients with AML. Fusion of ETV6 to the tyrosine kinase domain of TRKC (encoded by NTRK3) results in constitutive activation of the TRKC kinase, and ETV6-TRKC fusion protein expression has been shown to be sufficient for leukemogenesis. Constitutive activation of TRK family tyrosine kinases has also been detected in a wide range solid tumor and hematologic malignancies including lung, colorectal, salivary gland, sarcoma, thyroid, glioblastoma, melanoma, anaplastic large cell lymphoma, and Philadelphia-like acute lymphoblastic leukemia.

Entrectinib (RXDX-101) is an investigational, orally available, CNS-active, highly potent, and selective kinase inhibitor with low nanomolar potency against TRKA/B/C, ROS1 and ALK kinase activities (encoded by NTRK1/2/3, ROS1, and ALK genes, respectively). In these studies, we have demonstrated sensitivity to entrectinib in AML cell lines with endogenous expression of the ETV6-NTRK3 fusion gene. Entrectinib treatment blocked cell proliferation and induced apoptotic cell death in vitro with sub-nanomolar IC50 values. Phosphorylation of the ETV6-TRKC fusion protein, as well as phosphorylation of known TRKC downstream signaling effectors, was inhibited by entrectinib treatment in a dose-dependent manner. Sensitivity to entrectinib was dependent on expression of the TRKC fusion protein. In xenograft models, entrectinib treatment at clinically relevant doses resulted in tumor regression, which was accompanied by elimination of residual cancer cells from the bone marrow.

The clinical relevance of activated oncogenic tyrosine kinases resulting from chromosomal rearrangements has been validated by the efficacy of selective tyrosine kinase inhibitors. Entrectinib is currently the subject of STARTRK-2, an ongoing global phase 2 basket study enrolling patients across multiple tumor histologies containing TRK, ROS1, or ALK fusions. Our preclinical data demonstrate the potential of entrectinib as an effective treatment for patients with NTRK rearranged acute myeloid leukemia and provide a rationale for the clinical development of entrectinib in molecularly defined hematologic malignancies.

Citation Format: Patrick Fagan, Maria Barrera, Colin Walsh, Danielle Murphy, Ian Silverman, Robert Shoemaker, Ge Wei, Zachary Hornby, Gary Li, Kristen M. Smith. Antitumor activity of entrectinib, a highly potent pan-TRK, ROS1, and ALK inhibitor, in NTRK-fusion positive acute myeloid leukemia [abstract]. In: Proceedings of the Second AACR Conference on Hematologic Malignancies: Translating Discoveries to Novel Therapies; May 6-9, 2017; Boston, MA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(24_Suppl):Abstract nr 52.

Autonomous rehabilitation at stroke patients home for balance and gait: safety, usability and compliance of a virtual reality system

BACKGROUND

New technologies, such as telerehabilitation and gaming devices offer the possibility for patients to train at home. This opens the challenge of safety for the patient as he/she is called to exercise neither with a therapist on the patients' side nor with a therapist linked remotely to supervise the sessions.

AIM

To study the safety, usability and patient acceptance of an autonomous telerehabilitation system for balance and gait (the REWIRE platform) in the patients home.

DESIGN

Cohort study.

SETTING

Community, in the stroke patients' home.

POPULATION

Fifteen participants with first-ever stroke, with a mild to moderate residual deficit of the lower extremities.

METHODS

Autonomous rehabilitation based on virtual rehabilitation was provided at the participants' home for twelve weeks. The primary outcome was compliance (the ratio between days of actual and scheduled training), analyzed with the two-tailed Wilcoxon Mann-Whitney test. Furthermore safety is defined by adverse events. The secondary endpoint was the acceptance of the system measured with the Technology Acceptance Model (TAM). Additionally, the cumulative duration of weekly training was analyzed.

RESULTS

During the study there were no adverse events related to the therapy. Patients performed on average 71% (range 39 to 92%) of the scheduled sessions. The TAM Questionnaire showed excellent values for stroke patients after the training. The average training duration per week was 99±53min.

CONCLUSIONS

Autonomous telerehabilitation for balance and gait training with the REWIRE-system is safe, feasible and can help to intensive rehabilitative therapy at home.

CLINICAL REHABILITATION IMPACT

Telerehabilitation enables safe training in home environment and supports of the standard rehabilitation therapy.

Abstract 4698: Immuno-oncological efficacy of RXDX-106, a novel, selective and potent small molecule TAM (TYRO3, AXL, MER) inhibitor

The TAM family of receptor tyrosine kinases (RTKs), TYRO3, AXL, and MER, has been implicated in the pathogenesis and progression of many cancer types. In cancer cells, overexpression of TAM RTKs is associated with resistance and mesenchymal phenotype. In immune cells, TAM RTKs play a key homeostatic role as negative regulators of immune responses, contributing to the evasion of cancer cells from immune surveillance. Here we studied expression as well as functional modulation of TAM RTKs on immune cells in the tumor microenvironment and evaluated whether RXDX-106, a selective and potent, pseudo-irreversible small molecule inhibitor of TAM RTKs could restore and enhance host immunity against cancer. We first evaluated the expression of TAM RTKs on immune cells in non-tumor bearing mice and tumor bearing mice. Tumor bearing animals showed increased expression of TAM RTKs in subsets of immune cells such as lymph node macrophages and T cells, compared to non-tumor bearing mice. Particularly, TAM expression was upregulated in CD8+ T cells in tumors, suggesting that the increased expression could restrain T cell activation and mediate exhaustion. RXDX-106 reduced TAM phosphorylation on macrophages at concentrations as low as 2.5 nM, and inhibited AXL- and MER-dependent in vitro phagocytosis with an IC50 of 10.8 and 9.1 nM, respectively. In syngeneic mouse models, including 4T-1 breast cancer model and CT26 colon cancer model, RXDX-106 dose-dependently inhibited tumor growth and demonstrated further tumor growth inhibition in combination with anti-CTLA-4 or anti-PD-1 antibodies. The tumor growth inhibition was associated with increased total T cells, decreased T-regulatory cells, and increased IFN-γ production by NK cells in the tumor. RXDX-106 also increased IFN-γ levels in the blood when combined with anti-PD-1 antibody. Although RXDX-106 had no effect on T cell proliferation in vitro, it could increase the proliferation of T cells in lymph nodes in vivo. In conclusion, we demonstrated that tumors could induce TAM expression on subsets of T cells and that inhibition of TAM RTK activity by the small molecule inhibitor, RXDX-106, could potentially remove the molecular “brake” on immune activation in macrophages, NK cells and T cells, resulting in repolarization of the immune response towards an anti-tumor environment. The unique mechanism of activating both innate and acquired immunity by RXDX-106, and the compelling preclinical data in cell line and syngeneic models, support the clinical development of RXDX-106 in a wide variety of cancers.

Citation Format: Yumi Yokoyama, Erin D. Lew, Ruth Seelige, Colin Walsh, Maria Barrera, Elizabeth Tindall, Joanne Oh, Heather Ely, Amy Diliberto, Amanda Albert, Jack Bui, Gary Li. Immuno-oncological efficacy of RXDX-106, a novel, selective and potent small molecule TAM (TYRO3, AXL, MER) inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4698. doi:10.1158/1538-7445.AM2017-4698

External validity and reliability of the Psychosocial Assessment Tool (PAT) among Canadian parents of children newly diagnosed with cancer

BACKGROUND

The Psychosocial Screening Tool (PAT) was developed and validated with a sample of caregivers of children newly diagnosed with cancer in the United States. This study aimed to assess cultural adaptation (Phase 1) and validity and reliability of the revised PAT (PATrev) with a Canadian sample (Phase 2).

PROCEDURE

In Phase 1, a convenience sample of seven parents of children who were treated for cancer and six pediatric oncology healthcare experts participated. In Phase 2, 67 parents of children newly diagnosed with cancer from 4 Canadian pediatric cancer centers participated. To assess reliability and validity of the PATrev, parents completed behavioral (BASC-2) and quality of life (PedsQL) instruments about the child and an anxiety inventory (STAI) about themselves.

RESULTS

The PAT required minor changes to be culturally adapted for the Canadian population. The PATrev had strong inter-rater (0.77) test-retest (0.75), and internal consistency reliability (0.85), as well as moderate to strong validity comparing PATrev child's problems and PedsQL total (-0.49), PedsQL anxiety (-0.47), BASC-2 internalizing (0.64), behavioral (0.63), and adaptive scores (-0.56). PATrev discriminative validity was confirmed with BASC-2 scores (AUR scores of 0.70-0.74). PATrev parental stressors were strongly correlated to STAI scores (0.53). Finally, agreement between PATrev child's problems and parental anxiety scores was moderate (0.47).

CONCLUSION

This study supports the original PAT, demonstrates PATrev is a reliable and valid psychosocial screening tool, and provides unique evidence regarding early psychosocial risk in the family, which have important implications for guiding psychosocial practice.

Does the use of the revised psychosocial assessment tool (PATrev) result in improved quality of life and reduced psychosocial risk in Canadian families with a child newly diagnosed with cancer?

OBJECTIVES

Early psychosocial screening may guide interventions and ameliorate the adverse psychosocial effects of childhood cancer. The revised psychosocial assessment tool provides risk information - Universal (typical distress), Targeted (additional specific distress), and Clinical (severe distress) - about the child with cancer and his or her family. This pilot study investigated the benefits of providing a summary of family psychosocial risk information to the medical team treating the newly diagnosed child (Experimental Group, EG).

METHOD

We conducted a pilot randomized control trial with a sample of 67 parents, comparing the EG to the control group (CG) on parental perception of family psychosocial difficulties (revised psychosocial assessment tool risk levels), child behavior (behavior assessment scale for children-2), pediatric quality of life (PedsQL), and parental anxiety (state-anxiety scale of the state-trait anxiety inventory ), 2-4 weeks after diagnosis (Time 1) and 6 months later (Time 2).

RESULTS

Compared to the CG, participants in the EG had significantly reduced targeted and clinical risk (p < 0.001), and improved pain related PedsQL at Time 2 (p < 0.05). Scores for PedsQL total and nearly all subscales improved over time in both groups (p < 0.05 to p < 0.001). No changes in behavior scores were noted.

CONCLUSION

Preliminary findings suggest that providing a summary of the Psychosocial Assessment Tool to the treating team shortly after diagnosis may help reduce family wide psychosocial risk 6 months later and improve quality of life related to pain for children who are undergoing treatment for cancer.

Trajectory of parental hope when a child has difficult-to-treat cancer: a prospective qualitative study

OBJECTIVE

This prospective and longitudinal study was designed to further our understanding of parental hope when a child is being treated for a malignancy resistant to treatment over three time points during the first year after diagnosis using a qualitative approach to inquiry.

METHODS

We prospectively recruited parents of pediatric cancer patients with a poor prognosis who were treated in the Hematology/Oncology Program at a large children's hospital for this longitudinal grounded theory study. Parents were interviewed at three time points: within 3 months of the initial diagnosis, at 6 months, and at 9 months. Data collection and analysis took place concurrently using line-by-line coding. Constant comparison was used to examine relationships within and across codes and categories.

RESULTS

Two overarching categories defining hope as a positive inner source were found across time, but their frequency varied depending on how well the child was doing and disease progression: future-oriented hope and present-oriented hope. Under future-oriented hope, we identified the following: hope for a cure and treatment success, hope for the child's future, hope for a miracle, and hope for more quality time with child. Under present-oriented hope, we identified hope for day-to-day/moment-to-moment, hope for no pain and suffering, and hope for no complications.

CONCLUSIONS

For parents of children with a diagnosis of cancer with a poor prognosis, hope is an internal resource that can be present and future focused. These views fluctuated over time in response to changes in the child's well-being and disease progression.

Map on predicted deposition of Cs-137 in Spanish soils from geostatistical analyses

The knowledge of the distribution of (137)Cs deposition over Spanish mainland soils along with the geographical, physical and morphological terrain information enable us to know the (137)Cs background content in soil. This could be useful as a tool in a hypothetical situation of an accident involving a radioactive discharge or in soil erosion studies. A Geographic Information System (GIS) would allow the gathering of all the mentioned information. In this work, gamma measurements of (137)Cs on 34 Spanish mainland soils, rainfall data taken from 778 weather stations, soil types and geographical and physical terrain information were input into a GIS. Geostatistical techniques were applied to interpolate values of (137)Cs activity at unsampled places, obtaining prediction maps of (137)Cs deposition. Up to now, geostatistical methods have been used to model spatial continuity of data. Through semivariance and cross-covariance functions the spatial correlation of such data can be studied and described. Ordinary and simple kriging techniques were carried out to map spatial patterns of (137)Cs deposition, and ordinary and simple co-kriging were used to improve the prediction map obtained through a second related variable: namely the rainfall. To choose the best prediction map of (137)Cs deposition, the spatial dependence of the variable, the correlation coefficient and the prediction errors were evaluated using the different models previously mentioned. The best result for (137)Cs deposition map was obtained when applying the co-kriging techniques.

[Development of a nested polymerase chain reaction test for the diagnosis of transmissible gastroenteritis of pigs]

The aim of this study was to develop a nested polymerase chain reaction (nested PCR) for the rapid detection of transmissible gastroenteritis virus (TGEV) of pigs. The primers were designed on the basis of highly conserved regions of several TGEV sequences included in the analysis. External primers were used to amplify a fragment of the expected size (441 bp) in all the samples evaluated using reverse transcriptase polymerase chain reaction (RT-PCR), but with very low intensity. In the second amplification (nested PCR), internal primers were used to amplify a fragment of the expected size (168 bp), with good concentration. The performance of the test based on virus isolates in tissue culture and in clinical samples was judged good for the virological diagnosis of transmissible gastroenteritis of pigs.

Effectiveness and use of linezolid in hospitalisation wards

OBJECTIVE

To describe the use and effectiveness of linezolid as an alternative treatment for methicillin-resistant Staphylococcus aureus.

METHOD

Demographic, clinical and safety data were collected from hospitalised patients. The information sources were the clinical records and the pharmacy programme.

RESULTS

Thirty patients were treated with linezolid (median age 69.3, 63% male). The median duration of treatment was 8 days. The most prevalent indication was soft tissues and skin infections (46.7%). The indications were off-label in 40% of cases. Linezolid was used as a targeted therapy in 53%, especially for coagulase-negative Staphylococcus. Clinical healing occurred in 83.3%, and microbiological healing in 40%. Three patients (10%) experienced side effects from using linezolid.

CONCLUSION

The effectiveness and safety of linezolid is similar to that described in the trials. Its off-label use and the high number of empirical treatments mean that new strategies must be developed.

Feasibility and effectiveness of laparoscopic incisional hernia repair after liver transplantation

BACKGROUND

Incisional hernia is a frequent problem after liver transplantation. It is related to immunosuppression, use of steroids, obesity, as well as the type of incision. Laparoscopic repair shows a lower rate of complications in terms of infection and recurrence, as well as reduced postoperative pain and faster recovery.

METHODS

We reviewed our experience with laparoscopic incisional hernia repair (LIHR) in patients after liver transplantation, using the BARD Composix mesh which is composed of two layers of polypropylene and polytetrafluoroethylene (PTFE) and fixed with metal ProTack.

RESULTS

Between March 2002 and April 2010, we performed 20 LIHR in 17 male and three female subjects of overall mean age of 58.3 years, and body mass Index of 31.05 kg/m(2). The mean size of the defects was 215.25 cm(2). All patients had undergone bilateral subcostal incisions with a midline extension, and seven had additional operations after the transplantation for various reasons. There were no differences in immunosuppression. Three patients had needed steroid boluses for acute graft rejection episodes. There was no conversion of therapy. The size of mesh was 18 × 23 cm in seven cases and 20 × 25 in 12 cases. The mean postoperative hospital stay was 2.1 days. Oral feeding was initiated a few hours after surgery, and routine immunosuppression was not discontinued. There were no major early complications. During follow-up, we identified one patient with a mesh infection (5%) and one with a recurrence (5%).

CONCLUSION

LIHR is safe and feasible even for major hernias after liver transplantation with few complications.

Inventory and vertical migration of ¹³⁷Cs in Spanish mainland soils

In this study the total activity of (137)Cs deposited per unit area over the Spanish peninsular territory was analysed using a 150 × 150 km(2) mesh grid, with samples taken from 29 points. The deposited activities ranged between 251 and 6074 Bq/m(2). A linear relationship was obtained between these values and the mean annual rainfall at each sampling point which allowed a map to be drawn, using GIS software, which shows the distribution of total deposited (137)Cs activity across the Spanish mainland. At twelve of these sampling points the vertical migration profile of (137)Cs was obtained. These profiles are separated into two groups with different behaviour, one of which includes clay and loam soils and the other containing sandy soils. For both groups of profiles the parameters of the convective-diffusive model, which describes the vertical migration of (137)Cs in the soil, v (apparent convection velocity) and D (apparent diffusion coefficient) were calculated.

Hepatocellular carcinoma and liver transplantation: a 12-year experience

BACKGROUND

Orthotopic liver transplantation (OLT) for patients with cirrhosis and concomitant hepatocellular carcinoma (HCC) in early stages is the treatment of choice, with an acceptable recurrence rate and excellent survival.

AIM

We sought to evaluate (1) the accuracy of preoperative imaging; (2) the impact of pre-OLT treatments on survival and recurrence; and (3) the influence of beyond Milan criteria selection on global outcomes.

METHODS

We studied a cohort of 65 patients with HCC among 300 consecutive OLTs over a single 12-year experience. We analyzed the overall outcomes of survival and recurrence, the accuracy of preoperative diagnosis and staging the influence of neoadjuvant treatment prior to OLT, and the effect on overall outcomes beyond the Milan criteria in our series.

RESULTS

The 65 transplants were performed for HCC, mostly in association with hepatitis C virus and alcoholic cirrhosis with HTP. At a mean follow-up of 40.32 months, the recurrence rate was 5.7% among the 61 HCC confirmed by histopathology. The overall survival was 30.07. Actuarial survivals at 1, 5, and 10 years were 82%, 77%, and 62%, respectively. Six retransplants occurred among the seven graft losses albeit with poor survival after the second graft. Most explants showed low pTNM stages with favorable microscopic features. Preoperative imaging tests failed to achieve an accurate diagnosis in 15.38% of the series. The role of alpha-fetoprotein (AFP) and hepatic biopsy was irrelevant. Unfavorable histopathologic factors predicted a greater recurrence rate, but had no influence on survival. Neither recurrence nor survival were modified by pre-OLT therapy.

CONCLUSIONS

In our series, AFP, hepatic biopsy, and pre-OLT treatment had limited roles. Radiological imaging techniques underestimated HCC staging and lead to a misdiagnosis to an expected degree. Despite these findings, this single institution experience with OLT for HCC showed excellent survivals with a low recurrence rate including cases of patients beyond the Milan criteria.

A group social skills intervention program for survivors of childhood brain tumors

OBJECTIVE

The purpose of this study was to evaluate the feasibility and preliminary outcomes of a social skills group intervention program for child brain tumor survivors.

METHODS

Participants were 32 survivors (14 females) aged 8-18 years. Medulloblastoma (28%) was the main diagnosis. The intervention consisted of eight 2-hr weekly sessions focused on social skills including friendship making and assertion. Survivors and parents completed measures of social skills, quality of life, behavior and depression, at baseline, pre- and post-intervention, and 6 months later.

RESULTS

Feasibility analyses revealed promising acceptability, retention, recruitment, and treatment fidelity. Significant improvement was found after intervention based on parents' reports of self-control [F(1,27) = 5.97, p <.05], social skills [F(1,28) = 5.70, p <.05], and quality of life [F(1,15) = 17.98, p <.01].

CONCLUSIONS

The intervention is feasible and outcomes based on parental reports provide preliminary support for the efficacy of the program.

Age differences in perceived social support by paediatric haematopoietic progenitor cell transplant patients: a longitudinal study

OBJECTIVES

To describe longitudinally different sources of perceived social support by children and adolescents who undergo haematopoietic progenitor cell transplant (HPCT).

METHODS

Thirty-six (20 males, 16 females) survivors of paediatric HPCT, aged 8-18 years (Mean = 11.73), were assessed pre-HPCT and 6 months, 1 year and 2 years post-HPCT. Survivors were compared with siblings (n = 22) during the last assessment. The Social Support Scale for Children (SSSC), a self-report measure, provided scores on perceived social support from parents, teachers, friends and classmates.

RESULTS

Throughout the 2 years post-HPCT, perceived social support from all sources was generally higher for survivors than for population norms. Over time, both children and adolescents reported higher social support from parents than the normative values. Over time, children perceived higher support from teachers than did adolescents, whereas adolescents' perceived social support from classmates increased but children's decreased. Survivors and siblings did not differ significantly in their perceived social support 2 years post-BMT.

CONCLUSIONS

This exploratory study suggests that perceived parental support is equally important for children and adolescents but classmate and teacher social support varies with age. These developmental differences have important clinical implications for the care of these patients.

The Gap Study (GapS) interview--developing a process to determine the meaning and determinants of quality of life in children with arthritis and rheumatic disease

OBJECTIVE

Quality of Life (QOL) is a ubiquitous yet rarely precisely defined term. QOL may be determined by the differences (gaps) between our current situation and our expectations. Contemporary methods of measuring QOL often do not take these gaps into consideration. We performed this study to develop items and methods for measuring and valuing these gaps in order to better determine individual QOL for children with rheumatic diseases.

METHODS

We generated items from literature review, other QOL measures and interviews with pediatric rheumatology patients and their families. Gap-scales to measure the discrepancy between a child's current state and the expected or desired state were designed and tested iteratively in pilot interviews.

RESULTS

Thirty-one children (mean age=13.5 years, age range=6-17 years) and 22 parents were recruited through pediatric rheumatology clinics. The process of item generation, reduction and preliminary formatting yielded a list of 72 items. We developed a 3-point categorical scale of importance and a vertical visual analog scale (VAS) to determine individual valuation of items. 5 gap-scales were developed to reflect different aspects of the discrepancy between the child's current and expected or desired states for different QOL items.

CONCLUSIONS

We have developed a QOL interview based on theory that we can now test to see if it will enrich our understanding of the determinants of QOL in pediatric rheumatology patients and other chronically ill children.

Levels of 137Cs in muddy sediments of the seabed of the Bay of Cadiz, Spain. Part I. Vertical and spatial distribution of activities

This is the first of a two-part paper. This first part describes a detailed study conducted of the spatial and vertical distribution of the concentration of the radionuclide (137)Cs, utilising columns of sediment extracted from the seabed of the Bay of Cadiz (Spain) as specimens. The activity concentrations have been measured by means of gamma spectrometry using a HPGe detector and (137)Cs is used as an indicator of the sedimentation and contamination processes in the zone. At the same time the relationship between the levels of activity found and other hydrodynamic and sedimentological variables characteristic of the zone have been studied. The experimental results obtained will also serve to develop a model of the distribution of (137)Cs, which will be presented in the second part of this paper.

Levels of 137Cs in muddy sediments on the seabed in the Bay of Cadiz (Spain). Part II. Model of vertical migration of (137)Cs

This second part of the study reports the development of a model to describe the vertical migration of the artificial radioisotope (137)Cs in the sediment column on the seabed of the Bay of Cadiz. The application of the model provides an overall picture of the process of sedimentation in the Inner Bay of Cadiz. The spatial distribution of the rate of sedimentation enables us to study the sources of sediments and the means by which the sediments have been transported. A method has been derived from the rate of sedimentation to perform the dating of the layers of sediment. The model describes the behaviour of (137)Cs in the area under study, taking into account the time of residence in the zones that are the source of accumulation, the origin of the sedimentary material, together with the diffusion of the radionuclide in the sediment of the seabed.

Effect of telmisartan 80 mg once daily on 24-h blood pressure profile in patients with mild-to-moderate hypertension failing to respond to prior antihypertensive therapy

Blood pressure is not adequately controlled in almost 50% of patients with hypertension who are in receipt of antihypertensive therapy. This multicentre, prospective, open-label trial was designed to determine whether or not once-daily telmisartan 80 mg reduced blood pressure during the last 6 h of the 24-h dosing interval in patients with mild-to-moderate hypertension who were unresponsive to previous antihypertensive therapy. The study comprised 100 patients (47 males, 53 females) who had failed to respond satisfactorily to prior treatment given for a minimum of 3 months. At screening, 24-h ambulatory blood pressure monitoring (ABPM) was conducted after the patient had been treated with the currently prescribed antihypertensive medication. Following 5 weeks of telmisartan 80 mg treatment, ABPM was repeated. Telmisartan significantly reduced mean systolic blood pressure, diastolic blood pressure (DBP) and pulse pressure compared with previous antihypertensive therapy over each time interval (24-h, morning, night-time and the last 6 h of the dosing interval [2.00 a.m.-8.00 a.m.]) analysed. In addition, more than 90% of patients responded successfully (clinic DBP <90 mmHg or a >10 mmHg reduction in clinic DBP) at the end of telmisartan treatment. In conclusion, telmisartan provides effective blood pressure control throughout the 24-h dosing interval in patients with mild-to-moderate hypertension who were unresponsive to previous antihypertensive medication.

Ileal amino acid digestibility and performance of growing pigs fed wheat-based diets supplemented with xylanase

Two experiments were conducted to determine the effect of supplementation of xylanase to a wheat-based diet on the apparent ileal digestibility (AID) of AA and the performance of growing pigs fed diets limiting in AA. In Exp. 1, eight pigs (average initial BW = 20.5+/-1.2 kg) fitted with a simple T-cannula at the distal ileum, were fed four diets according to a repeated 4 x 4 Latin square design. Diet 1 was a basal diet that contained 97.6% wheat. Diets 2, 3, and 4 were the basal diet supplemented with xylanase at rates of 5,500, 11,000, and 16,500 units of xylanase activity (XU), respectively (as-fed basis). There were linear and quadratic effects (0.062 < P < 0.001) of xylanase supplementation on the AID of CP and most of the AA. The largest increases in AID of CP and AA were obtained when xylanase was supplemented at a rate of 11,000 XU; no further increases were observed with xylanase supplementation at a rate of 16,500 XU. In Exp. 2, 30 pigs (average initial BW 21.4+/-1.8 kg) were randomly allotted to six dietary treatments. Diets 1 to 4 were similar to those used in Exp. 1. Diet 5 was the same as Diet 1, but supplemented with 0.53% lysine, 0.12% threonine, and 0.05% methionine. Diet 6 (positive control diet) was a wheat-soybean meal diet that contained 18.2% CP (as-fed basis). The total contents of lysine, threonine, and methionine were similar for Diets 5 and 6. There was a linear effect of xylanase supplementation on ADG (P = 0.093) and feed:gain ratio (P = 0.089), and a quadratic effect on ADG (P = 0.067) and feed:gain ratio (P = 0.074). But, the greatest response was obtained with the supplementation of 11,000 XU. The supplementation of lysine, threonine, and methionine to Diet 1 increased (P = 0.001) ADG and ADFI and improved (P = 0.01) feed:gain ratio. There was no difference (P = 0.508) in the performance of pigs fed the AA-supplemented or control diet. In conclusion, the supplementation of xylanase to a diet in which wheat provided the sole source of protein and energy improved the AID of AA, ADG, and feed:gain ratio; however, this improvement was very small compared with that obtained with the supplementation of synthetic amino acids.