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Neurologic complications of oncologic therapies are occurring with increasing frequency in cancer patients. This is a result of the availability of a growing number of treatments associated with neurotoxicities and prolonged patient survival. Increased understanding of the underlying mechanisms for these neurologic complications and methods to prevent them will be an important challenge for the future and will hopefully lead to reduced neurologic morbidity in cancer patients. This chapter provides a comprehensive overview of how cancer therapies, including radiation, chemotherapy, and biologic agents, affect the nervous system.

The somatic embryogenesis (SE) capacity of megagametophytes belonging to Continental and Mediterranean Spanish provenances of maritime pine (Pinus pinaster Aiton) was studied, noting factors (megagametophyte developmental stage and culture medium) that enhanced the induction and establishment of SE lines. In both provenances, initiation and establishment of embryogenic calli was higher on megagametophytes in which the dominant zygotic embryo had begun to develop. In the Mediterranean provenance, however, SE lines were also established from megagametophytes enclosing zygotic embryos with well-developed cotyledons. A modified Litvay medium (mLV) containing 9.9 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 4.4 μM 6-benzyladenine (BA) was superior to DCR medium containing 13.6 μM 2,4-D and 4.4 μM BA for SE induction, but there were no differences between media in terms of the number of SE lines established after 4 months in culture (153 vs. 155 established SE lines, for mLV and DCR media respectively). Of the 26 embryogenic lines tested for maturation, 15 (58 %) produced cotyledonary somatic embryos and 75 % of these gave rise to plants on germination medium. SE-like cultures from adult maritime pine trees were also initiated, but embryogenic lines could not be established. This is the first report on the production of SE in maritime pine of Continental and Mediterranean origin. The micropropagation protocols presented here provide an important tool for the vegetative multiplication of selected families and breeding programs for maritime pines from Spain.

In this case, a woman with refractory diffuse large-B-cell lymphoma had a CNS recurrence that responded completely to anti-CD19 CAR T-cell therapy. After biopsy of a subsequent skin recurrence, the lesions cleared in association with an expansion of the CAR T cells in the blood.

The effectiveness of thidiazuron (TDZ) in promoting in vitro organogenesis in cultured embryo axes and cotyledons from two Spanish Mediterranean provenances of Pinus pinaster Aiton is reported. Application of 44.4 μM TDZ as a 6-d pulse on DCR medium and subsequent transference of maritime pine explants to the same medium without growth regulators, but supplemented with activated charcoal, produced between 17 and 19 axillary shoots per embryo axis with no differences between the two provenances. The same sequential treatment allowed adventitious shoot differentiation on 75% of the cotyledons, with a mean of 12.2 shoots regenerated per explant. Axillary and adventitious shoots were rooted ex vitro after an auxin pulse of indole-3-butyric acid and 1-naphthaleneacetic acid. The micropropagation protocols presented here should enable vegetative multiplication of selected families, and elite trees from these Spanish Mediterranean provenances of maritime pine.

BACKGROUND: Isocitrate dehydrogenase (IDH) mutant tumors represent a distinct subtype among diffuse gliomas, with improved prognosis compared to grade-matched IDH wild-type tumors. As a basis for clinical trial design of IDH-targeting drugs, we sought to describe outcomes exclusively within the glioma subgroup defined by IDH1 mutation. METHODS: We retrospectively analyzed 275 IDH mutant glioma patients (48.7% grade II and 51.3% grade III tumors; 65.5% astrocytic and 34.5% oligodendroglial tumors) treated at our institution. We calculated progression and survival statistics, including median time to second progression event following first episode of recurrence, using the method of Kaplan-Meier. Estimated survival proportions were correlated with molecular, histologic and clinical factors. RESULTS: During a median follow-up of 6.4 years, 44 deaths (7.6%) and 149 first progression events (54.1%) were observed, with estimated median PFS of 5.7 years (95% CI 4.7–6.4) and median OS of 18.7 years (95% CI 12.2 years - not reached). We validated the effect of grade, molecular diagnosis and treatment paradigms on PFS in our cohort and found results consistent with existing literature. Following the first episode of progressive disease, 79 second progression events occurred during a median follow-up period of 4.1 years. The estimated PFS following first progressive event (PFS-2nd) is 3.0 years (95% CI 2.1–4.1). CONCLUSION: This well-characterized cohort of IDH mutant glioma patients demonstrate progression and survival outcomes reflecting published literature and serves as a reasonable historical control population. Notably, the PFS interval accelerates during disease course, with interval between first to second recurrence (3.0 years) shorter than time from diagnosis to first recurrence (5.7 years). The novel survival statistic PFS-2nd offers an accurate and relevant surrogate outcome for the design of clinical trials investigating experimental drug efficacy at recurrence. These findings highlight that inappropriate comparison to historical baseline PFS may result in prematurely abandoning promising agents.

BACKGROUND: H3 K27M-mutant gliomas have a dismal clinical prognosis and no proven curative therapy. We report the updated clinical experience with ONC201, the first cancer-specific DRD2 antagonist, in adult and pediatric H3 K27M-mutant gliomas. METHODS: As of May 28, 2018, 26 patients with H3 K27M-mutant glioma have been treated with ONC201: 9 pediatric (18 years old). Twelve patients had recurrent disease and 14 had previously-treated stable disease prior to initiating ONC201. Patients had 1–4 prior lines of therapy and all received prior radiation. Ten adult patients were enrolled on clinical trials and the other 16 were on compassionate use. ONC201 was orally administered at 625 mg to adults and scaled by body weight for pediatric patients. All patients, except one, were dosed weekly. RESULTS: Fourteen of 26 patients (54%) remain progression-free on ONC201 with a median follow up of 3.6 (range 1.6–24.5) months. No dose modifications or discontinuation due to toxicity have occurred. Among the 12 adult patients with recurrent disease who received single agent ONC201, the estimated PFS6 is 36.5%. Seven patients have experienced radiographic and/or clinical benefit (neurological stabilization or improvement). Among the 5 adults with recurrent thalamic glioma, three have experienced durable complete regression of their thalamic tumors, including the first H3 K27M-mutant glioma patient treated with ONC201 who has experienced 96% regression of her recurrent disease and continues single agent ONC201 for >2 years. Two DIPG pediatric patients who initiated single agent ONC201 6–8 weeks after radiation have experienced radiographic and neurological improvements and exhibited PFS of >13 months from diagnosis. CONCLUSIONS: Emerging clinical data suggest that ONC201 exhibits clinical activity for some patients with H3 K27M-mutant glioma.

Newly diagnosed GBM represents a population of increased focus in early phase clinical trials. However, a key limitation of current genomic databases of GBM, such as TCGA, is that patient populations eligible for inclusion in these databases exhibit inherent biases and exhibit limitations on the quality of clinical and imaging data available for integration with genomics. To address these limitations and to better represent the genomics of patient populations commonly enrolled to early phase clinical trials, we prospectively consented and enrolled GBM patients to the Ivy Foundation Glioblastoma Patient Atlas Project. A total of 1591 patients from 7 participating sites of the Ben and Catherine Ivy Foundation Consortium for Early Phase Clinical Trials were consented to the project and clinical data was entered into a centrally managed clinical trials database. Overall 658 subjects had pre- and post-surgical imaging centrally reviewed and recorded and 387 subjects had sufficient tissue for completion of targeted exome sequencing of approximately 500 cancer causing genes (Oncopanel or Impact). More than 308 subjects had a complete set of genomics, imaging, and clinical data, including TMZ/RT use, KPS, progression, and steroid use. Histopathological features, MGMT, and IDH mutation status were also annotated. Of the subjects with full clinical data, 171 had expired by the time of last analysis of the cohort. Genomic and clinical characteristics unique to the early phase clinical trial population compared to TCGA and other cohorts of GBM were identified and radio-genomic and other advanced population-based analyses were performed. All clinical, genomic and imaging data are being utilized to create an Ivy cBio Portal for sharing of this rich dataset within the neurooncology community.

BACKGROUND: Glioblastoma and tumor endothelial cells express phosphatidylserine, a highly immunosuppressive membrane phospholipid. Bavituximab a chimeric monoclonal antibody binds to 2-glycoprotein 1 (2-GP1) to form a complex of 2-GP1 with phosphatidylserine, resulting in immune activation against tumor cells and anti-angiogenic effects. Phase I/II trials in other solid cancers have demonstrated response rates up to 85% when bavituximab was given with cytotoxic chemotherapy. Pre-clinical data in glioblastoma models suggested synergistic effects of phosphatidylserine blockade, radiation, and temozolomide (TMZ). METHODS: In this ongoing phase II trial (NCT03139916), adult patients with IDH-wild-type newly diagnosed glioblastoma receive 6 weeks of chemoradiation, followed by 6 cycles of adjuvant TMZ (C1-C6 aTMZ). Bavituximab (3 mg/kg) is given weekly, starting week 1 of chemoradiation, for 18 weeks with the option to continue if tolerated. Physiologic MRIs are performed pre-treatment, pre-C1, pre-C3, and pre-C5 aTMZ. Within the enhancing tumor region, we measured median tumor Ktrans (reflecting vascular permeability) and relative cerebral blood volume (rCBV). Median percent changes during treatment were compared to pre-treatment values. RESULTS: To date, 25 of 36 anticipated patients have enrolled (10 with MGMT promoter methylation). All patients underwent pre-treatment scans. 13 have evaluable pre-C1 and 8 pre-C3 aTMZ scans. On the pre-C1 MRIs, enhancing volume decreased by 39% and median tumor Ktrans and rCBV did not change significantly. On the pre-C3 MRIs, enhancing volume decreased by 11% and Ktrans and rCBV decreased by 17% and 21%, respectively. Five patients experienced radiographic disease progression after a median of 2.6 months and 1 patient died 76 days after diagnosis due to disease progression. Bavituximab was generally well tolerated. CONCLUSIONS: Combining bavituximab with radiation and temozolomide results in decreased enhancing tumor volume, permeability, and cerebral perfusion. Continued patient accrual and imaging marker evaluation are underway to investigate the correlation between bavituximab, MRI changes, and survival.

D2-like dopamine receptors (DRD2/3/4) are G protein-coupled receptors (GPCRs) that are overexpressed in glioblastoma (GBM) and their antagonism induces tumor cell apoptosis. We describe the first selective DRD2/3 antagonist for neuro-oncology using computational, receptor pharmacology, biochemical and clinical studies. Consistent with an in-silico prediction and in contrast to antipsychotics that target several dopamine receptors and other GPCRs, β-arrestin recruitment and cAMP assays determined that ONC201 is a selective DRD2/3 antagonist. Schild analyses and radioligand competition assays revealed competitive and non-competitive DRD2 antagonism with a potency (2-3 µM) that is consistent with anticancer activity and driven by an unusually slow association rate. Proof-of-concept studies show that selective DRD2 inhibition induces superior anti-cancer efficacy relative to pan-targeting of the dopamine receptor family. In accordance with superior selectivity, ONC201 also exhibited a wider therapeutic window compared to antipsychotics. Shotgun mutagenesis across 350 amino acids of DRD2 identified 8 residues that are critical for ONC201-mediated DRD2 antagonism. Consistent with competitive inhibition, several mutated residues were within the orthosteric binding site. However, distal residues were identified that were not involved in DRD2 antagonism by antipsychotics and may explain the selectivity and non-competitive antagonism of ONC201. In vitro and in vivo studies have previously demonstrated single agent ONC201 efficacy in GBM models (Allen et al 2013). Analyses of The Cancer Genome Atlas and tissue microarrays revealed high DRD2 expression relative to other dopamine receptors, correlation with poor prognosis and high DRD2 expression in primary rather than secondary GBM. A linear correlation between DRD2 mRNA and ONC201 GI50 was observed among GBM cell lines in the NCI60 panel. Interestingly expression of DRD5, a D1-like dopamine receptor that counteracts DRD2 signaling, was significantly inversely correlated with ONC201 potency in the NCI60 dataset (P Citation Format: Varun Vijay Prabhu, Neel Madhukar, C. Leah B. Kline, Rohinton Tarapore, Wafik S. El-Deiry, Joseph Rucker, Benjamin Doranz, Faye Doherty, Alexander VanEngelenburg, Jessica Durrant, Cyril Benes, Sean Deacon, Neil Charter, R. Benjamin Free, Wolfgang Oster, David Sibley, Isabel Arrillaga, Olivier Elemento, Joshua E. Allen. Selective targeting of dopamine receptor dysregulation in high grade gliomas with imipridone ONC201 [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 3857.

2059Background: ONC201 is a DRD2 antagonist in Phase II trials for cancers that exhibit dysregulation of the dopamine pathway. We previously reported an objective response in the first recurrent H3...

e14034Background: ONC201 is an antagonist of the G protein-coupled receptor DRD2 that crosses the blood-brain barrier and induces tumor cell apoptosis in preclinical models. The anti-tumor activity of ONC201 is pronounced in cells with low DRD5 expression and is associated with induction of the ATF4/CHOP/DR5-mediated integrated stress response pathway to trigger apoptosis. We previously reported the single agent activity of ONC201 in 17 adult patients with recurrent glioblastoma that demonstrated the safety, systemic pharmacodynamics, and a durable objective response when administered orally once every 3 weeks. Here, we evaluated the intratumoral drug concentrations and pharmacodynamic activity of ONC201 in adult recurrent glioblastoma patients who were treated on a weekly schedule. Methods: Six patients ≥18 years old with first recurrence of glioblastoma who were eligible for salvage surgical resection were enrolled. ONC201 was administered orally as 625 mg once a week. Salvage surgery was performed appr...

2003Background: Multi-dimensional genomic analyses may improve outcome in glioblastoma (GB) but are not widely available as routine clinical care. ALLELE is an ABC2-funded consortium to generate pr...

Background: ONC201, an imipridone that is a selective antagonist of the G protein-coupled receptors dopamine receptor D2 (DRD2) and D3 (DRD3), has exhibited biologic activity and an exceptional safety profile in a phase II study in bevacizumab-naïve recurrent glioblastoma (Arrillaga et a.l, 2017). Single-agent ONC201 efficacy has been observed in preclinical glioblastoma models in addition to robust penetrance of the blood-brain barrier (Allen et al., 2013). DRD2 antagonism induces tumor cell apoptosis via the same signaling pathways affected by ONC201. In addition, DRD2 is expressed on NK and other immune cells and DRD2 antagonism can induce their activation. Methods: Cell viability assays were performed with ONC201 in >1000 Genomic of Drug Sensitivity in Cancer (GDSC) cell lines and NCI60. Immunohistochemistry staining of DRD2/DRD5 was performed in glioblastoma tissue microarrays and archival tumor tissues. Whole exome sequencing was performed in RKO cells with acquired resistance to ONC201. DRD5 wild-type and mutant constructs were generated for overexpression studies. ELISA was used to quantitate serum prolactin and immune effector (perforin) levels. Intratumoral drug concentrations were evaluated by LC-MS assays conducted on glioblastoma tissue resected from patients following the second dose of 625mg ONC201. Results: Evaluation of ONC201 in GDSC cell lines confirmed broad anticancer efficacy with high sensitivity (~1-3 µM) in human brain cancer. The Cancer Genome Atlas (TCGA) revealed that DRD2 is highly expressed in glioblastoma relative to other dopamine receptors and that genetic aberrations are rare. High expression of DRD2 occurred in primary, rather than secondary, glioblastoma and was associated with a poor prognosis. Immunohistochemistry of tissue microarrays revealed DRD2 overexpression in glioblastoma relative to normal brain. A linear correlation between DRD2 mRNA and ONC201 GI50 was observed among glioblastoma cell lines in the NCI60 panel. Interestingly, expression of DRD5, a D1-like dopamine receptor that counteracts DRD2 signaling, was significantly inversely correlated with ONC201 potency in the NCI60 and GDSC datasets (P 5 month had no detectable expression of DRD5, unlike those with PFS Citation Format: Varun Vijay Prabhu, Neel Madhukar, C. Leah B. Kline, Rohinton Tarapore, Wafik El-Deiry, Olivier Elemento, Faye Doherty, Alexander VanEngelenburg, Jessica Durrant, Andrew Zloza, Cyril Benes, Isabel Arrillaga, Wolfgang Oster, Joshua E. Allen. Targeting DRD2 dysregulation in recurrent glioblastoma with imipridone ONC201: predictive and pharmacodynamic clinical biomarker analyses [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A060.

Spike lavender (Lavandula latifolia) essential oil is widely used in the perfume, cosmetic, flavouring and pharmaceutical industries. Thus, modifications of yield and composition of this essential oil by genetic engineering should have important scientific and commercial applications. We generated transgenic spike lavender plants expressing the Arabidopsis thaliana HMG1 cDNA, encoding the catalytic domain of 3-hydroxy-3-methylglutaryl CoA reductase (HMGR1S), a key enzyme of the mevalonic acid (MVA) pathway. Transgenic T0 plants accumulated significantly more essential oil constituents as compared to controls (up to 2.1- and 1.8-fold in leaves and flowers, respectively). Enhanced expression of HMGR1S also increased the amount of the end-product sterols, beta-sitosterol and stigmasterol (average differences of 1.8- and 1.9-fold, respectively), but did not affect the accumulation of carotenoids or chlorophylls. We also analysed T1 plants derived from self-pollinated seeds of T0 lines that flowered after growing for 2 years in the greenhouse. The increased levels of essential oil and sterols observed in the transgenic T0 plants were maintained in the progeny that inherited the HMG1 transgene. Our results demonstrate that genetic manipulation of the MVA pathway increases essential oil yield in spike lavender, suggesting a contribution for this cytosolic pathway to monoterpene and sesquiterpene biosynthesis in leaves and flowers of the species.

The increasing interest in natural products from a renewable source has encouraged growers to reintroduce indigo-producing crops into the European agriculture. We studied agronomic conditions (sowing date, plant density, nitrogen fertilization, irrigation rate, seedling transplanting) influencing production of the blue pigment indigo, from Isatis tinctoria and I. indigotica crops in a Mediterranean region of Spain (Valencia). I. tinctoria was more suitable for cultivation in our climate conditions than I. indigotica . Indigo yield from Spanish I. tinctoria trials was greater than in Northern and Central Europe. Furthermore, indigo production was maintained when water and nitrogen supplies were significantly restricted, showing that I. tinctoria is not a high-demanding crop.

Reversed-phase HPLC analysis and random amplified polymorphic DNA (RAPD) markers were used to monitor DNA methylation status and genetic stability of C. atlantica and C. libani shoots generated through axillary bud proliferation. Average DNA methylation in C. atlantica or C. libani seedlings and mature 200-year-old trees of C. libani was 19.8, 19.5 and 22.3%, respectively. These global amounts showed no significant variation after the in vitro establishment of seedling-originated shoot stocks. In contrast, in vitro culture caused a significant decrease in the amount of 5-methylcytosine in genomic DNA of the tissue culture (TC) progenies of one of the adult C. libani genotypes. This DNA demethylation event accompanied an enhancement of the regrowth capacity of this genotype. Detected RAPD variation between mother plants and their TC progenies was species-related, with C. libani TC progenies being genetically more stable than those of C. atlantica. Nevertheless, similarity indices ranged from 0.97 to 1 among mother plants and their TC progenies. Furthermore, the analyses of molecular variance (AMOVA) suggest that RAPD variation among the mother plants and their TC progenies might be considered as not significant. The application of various statistical approaches, including cluster-based genetic distance methods and AMOVA, demonstrates that RAPD markers discriminate C. atlantica and C. libani appropriately.

A protocol based on SAAT (sonication-assisted Agrobacterium-mediated transformation) has been developed to obtain herbicide-resistant transgenic black locust (Robinia pseudoacacia L.) plants. Cotyledon explants were co-cultivated with Agrobacterium AGL1 strain carrying the pTAB16 plasmid (bar and gusA genes). The effects of bacterial concentration (OD550 of 0.3, 0.6, 0.8) and method of infection (sonication vs immersion) on bacterial delivery were determined by assaying cotyledons for transient beta-glucuronidase expression 3 days after infection. SAAT increases transient expression efficiency especially at an OD550 of 0.6. After determining bacterial concentration and infection method, other factors affecting transformation efficiency, such as explant preconditioning and period of time before applying selection, were tested. From these experiments, the preferred protocol for black locust cotyledon transformation should include sonication of preconditioned cotyledons in AGL1 suspension, coculture for 3 days with 100 microM acetosyringone and transfer to selection medium with 4 mg/l phosphinothricin and 150 mg/l timentin. Of the initial explants, 2% produced at least one transgenic shoot. Genetic transformation was confirmed by Southern hybridization, chlorophenol red assay and herbicide tolerance of the regenerated plants.

ONC201, an imipridone that is a selective antagonist of the G protein-coupled receptors dopamine receptor D2 (DRD2) and D3 (DRD3), has exhibited tumor shrinkage and an exceptional safety profile in a phase II recurrent glioblastoma clinical trial (Arrillaga et al, 2017). In vitro and in vivo studies have previously demonstrated single agent ONC201 efficacy in glioblastoma models (Allen et al 2013). In vitro efficacy profiling of ONC201 in the Genomic of Drug Sensitivity in Cancer (GDSC) collection of cell lines confirmed broad anti-cancer efficacy with high sensitivity in human brain cancer cell lines. DRD2 is overexpressed in glioblastoma and DRD2 antagonism induces tumor cell apoptosis via the same signaling pathways that respond to ONC201. Investigation of The Cancer Genome Atlas (TCGA) revealed that DRD2 is highly expressed in glioblastoma relative to other dopamine receptor family members and that genetic aberrations were rare. High expression of DRD2 occurred in primary, rather than secondary, glioblastoma and was associated with a poor prognosis. Immunohistochemistry analyses of tissue microarrays revealed DRD2 overexpression in glioblastoma relative to normal brain. A linear correlation between DRD2 mRNA and ONC201 GI50 was observed among glioblastoma cell lines in the NCI60 panel. A significant induction of serum prolactin, a surrogate biomarker of target engagement, was detected in ONC201-treated glioblastoma patients. Interestingly, expression of DRD5, a D1-like dopamine receptor that counteracts DRD2 signaling, was significantly inversely correlated with ONC201 potency in the NCI60 and GDSC datasets (P

INTRODUCTION Histone H3 K27M mutations distinguish a subgroup of midline gliomas in children and young adults with devastating prognosis for which there are no effective medical therapies. In a recent phase 2 trial in adult recurrent glioblastoma with ONC201, a small molecule selective antagonist of the dopamine receptor D2 (DRD2) and D3 (DRD3), a 22 year old female with recurrent H3 K27M mutant glioblastoma had tumor regression of 92% that has persisted >15 months. Furthermore, antiseizure medication was discontinued and no ONC201 side effects were observed. Based on this exceptional response, we tested whether H3 K27M mutant gliomas were selectively sensitive to ONC201-induced apoptosis.

The prognostic significance of residual contrast enhancing tumor volume after initial surgery to predict OS in newly diagnosed GBM remains poorly understood and not controlled for in prospective clinical trials. In the current study we pooled imaging data in >1,400 newly diagnosed GBM patients from international multicenter clinical trials, single institution databases, and multicenter clinical trial consortiums identify relationships between clinical parameters, MGMT methylation status, treatment, and residual enhancing tumor volume on OS.

The prognostic significance of tumor location in newly diagnosed GBM (NDGBM) remains provocative and poorly understood. In this study we pooled imaging data in >1,400 NDGBM patients from international multicenter clinical trials, single institution databases, and multicenter clinical trial consortiums to identify relationships between tumor location on OS, independent of clinical and genetic or molecular characteristics.

Summary Shoot formation in explants of Digitalis minor was achieved, through axillary bud proliferation and adventitious bud differentiation, by varying the amount and source of plant hormones. Shoot regeneration was also obtained after infection of D. minor with the wild-type Agrobacterium tumefaciens strain 82.139, which induced shooty tumours. These shoots were not transgenic, as revealed by nopaline assays and the use of a C58pMP90/T139GUS-INT strain harbouring the intron inactivated gusA gene. Plants were easily rooted and transplanted into the greenhouse. Shoot cultures of D. minor accumulated up to 226 μg cardenolides per g dry mass when cultured on agar-solidified medium. Cardenolide content was significantly lower in submerged shoot cultures, the effect being related to a high incidence of hyperhydricity. Greenhouse-grown plants presented the highest amounts of these metabolites. This is the first report on micropropagation of the Balearic endemic medicinal plant species D. minor . The induction of caulogenic galls by A. tumefaciens wild strain 82.139 opens new possibilities for the biotechnological improvement of Digitalis spp.

TPS2079 Background: Patient with glioblastoma (GBM) with unmethylated MGMT promoters derive limited benefit from temozolomide (TMZ) and have dismal outcome. Prioritizing the numerous available therapies and biomarkers for late stage testing requires an efficient clinical testing platform. INSIGhT (NCT02977780) is a biomarker-based, Bayesian adaptively randomized, multi-arm phase II platform screening trial for patients with newly diagnosed GBM and unmethylated MGMT promoters. Methods: INSIGhT compares experimental arms to a common control of standard concurrent TMZ and radiation therapy (RT) followed by adjuvant TMZ. The primary endpoint is overall survival (OS). Patients with newly diagnosed, unmethylated GBM that are IDH R132H mutation negative, and with genomic data available or who consent to whole exome sequencing through the ALLELE companion study for biomarker grouping are eligible. Two experimental arms consist of concurrent RT/TMZ followed by adjuvant neratinib (EGFR, HER2, and HER4 inhibitor) or abemaciclib CDK 4/6 inhibitor), respectively, in place of TMZ. The other experimental arm is CC-115 (TORC1/2 and DNA PK inhibitor), which replaces TMZ in both the concurrent and adjuvant phases. Biomarker groups include: EGFR + patients with EGFR amplification/mutation; PI3K + patients with PIK3CA mutation/amplification, PIK3R1 mutation, AKT3amplification, PIK3C2B > 1 copy gain, or PTEN dual loss; CDK: + patients with wild-type RB1 and CDK4 amplification, CDK6 amplification, or CDKN2A > 1 copy loss. Given the lack of pretrial biomarker data and the anticipated overlap of the groups, randomization will initially be equal. As the trial progresses, randomization probabilities will be adapted based on the Bayesian estimation of the probability of treatment impact on progression-free survival (PFS). These randomization probabilities can vary among the biomarker groups so predictive biomarkers will be identified and utilized if present. Treatment arms may drop due to low probability of treatment impact on OS, and new arms may be added. Experimental arms are compared only with control and should be thought of as discrete experimental questions, with INSIGhT being open to new investigators with proposed therapeutic hypotheses. Clinical trial information: NCT02977780.

SUMMARY Glioblastoma is the most prevalent malignant primary brain tumor in adults and to date effective durable treatments are lacking. Preclinical studies underscore the importance of neovascularization for tumor survival, making angiogenesis an important treatment target. Early clinical experience in recurrent glioblastoma suggested that antiangiogenic agents may provide clinical benefit by prolonging progression-free survival, improving quality of life and decreasing peritumoral edema. Two recent Phase III randomized trials of antiangiogenic therapy at initial diagnosis suggested improvement in progression-free survival, but failed to show an overall survival benefit. Ongoing preclinical research focuses on mechanisms of resistance and potential predictive biomarkers. Identification of targets to resistance pathways and of predictive biomarkers will hopefully improve efficacy of antiangiogenic therapies.

[EN] The potential of haploid tissues for genetic studies in conifers is hampered by the lack of abundant and homogeneous plant material suitable for DNA isolation. In this work we have determined factors promoting haploid callus induction and proliferation from megagametophytes of Oria 6, a genotype of Pinus pinaster Aiton (maritime pine) from the natural population Sierra de Oria (Almeria, Spain), selected based on its response to extreme drought conditions. The generation of haploid callus was restricted to megagametophytes isolated from light-brown cones with no dehydrated seeds collected in September. Culture medium composition did not significantly affect callus induction, but a modified Murashige and Skoog medium with 2,4-dichlorophenoxyacetic acid and 6-benzyladenine favored further multiplication. The ploidy status of the callus lines was determined by flow cytometry and seven polymorphic microsatellites. A total of sixteen haploid callus lines were established and one of these is being used as a source of DNA for massive sequencing of maritime pine genome., Research funds were provided by Spanish National projects (BIO2007-29814 and BIO2010-12302-E) and Generalitat Valenciana (Prometeo/2009/075). The research leading to these results has also received funding from the European Union’s Seventh Framework Programme (FP7/2007–2013) under Grant Agreement No. 289841 (ProCoGen). We thank M. A. Morcillo for technical assistance, Dr. Jose´ Juarez (Instituto Valenciano de Investigaciones Agrarias, IVIA, Spain) and Dr. Vesselina Nikolova (Vegetable Crops Research Institute, Plovdiv, Bulgaria) for their support in the flow cytometry and karyological analyses, respectively.

SummaryThis paper reports on protocols for in vitro plant regeneration, gene transfer and on shoot salt tolerance from two accessions of L. cheesmanii (Riley). Shoot organogenesis was achieved on media with zeatin or BA/IAA combinations. The two accessions tested, LA1401 and LA530, showed differences in both their aptitude to regenerate and their salt tolerance in vitro. The accession LA530 had a higher organogenic potential than LA1401 (97% vs. 80% of organogenic explants). In contrast, none of the LA530 isolated shoots rooted when cultured in full strength MS-modified medium supplemented with 200.mM NaCl while 93% of shoots from LA1401 formed roots. Finally, Agrobacterium-mediated transformation was used to introduce the nptII and uidA marker genes into the salt tolerant accession LA1401. Eight to nine per cent of the cotyledon explants produced transgenic plants. After self-pollination, the inheritance analysis showed a Mendelian segregation of both transgenes. The collection of transgenic plants will ...

Overexpression of the HAL1 gene in yeast has a positive effect on salt tolerance by maintaining a high internal K+ concentration and decreasing intracellular Na+ during salt stress. In the present work, the yeast geneHAL1 was introduced into tomato (Lycopersicon esculentum Mill.) by Agrobacterium tumefaciens-mediated transformation. A sample of primary transformants was self-pollinated, and progeny from both transformed and non-transformed plants (controls) were evaluated for salt tolerance in vitro and in vivo. Results from different tests indicated a higher level of salt tolerance in the progeny of two different transgenic plants bearing four copies or one copy of the HAL1 gene. In addition, measurement of the intracellular K+ to Na+ ratios showed that transgenic lines were able to retain more K+ than the control under salt stress. Although plants and yeast cannot be compared in an absolute sense, these results indicate that the mechanism controlling the positive effect of theHAL1 gene on salt tolerance may be similar in transgenic plants and yeast.

Transgenic plants of the aromatic shrub Lavandula latifolia (Lamiaceae) were produced using Agrobacterium tumefaciens-mediated gene transfer. Leaf and hypocotyl explants from 35–40-day old lavender seedlings were inoculated with the EHA105 strain carrying the nptII gene, as selectable marker, and the reporter gusA gene with an intron. Some of the factors influencing T-DNA transfer to L. latifolia explants were assessed. Optimal transformation rates (6.0 ± 1.6% in three different experiments) were obtained when leaf explants precultured for 1 day on regeneration medium were subcultured on selection medium after a 24 h co-cultivation with Agrobacterium. Evidence for stable integration was obtained by GUS assay, PCR and Southern hybridisation. More than 250 transgenic plants were obtained from 37 independent transformation events. Twenty-four transgenic plants from 7 of those events were successfully established in soil. β-glucuronidase activity and kanamycin resistance assays in greenhouse-grown plants from two independent transgenic lines confirmed the stable expression of both gusA and nptII genes two years after the initial transformation. Evidence from PCR data, GUS assays and regeneration in the presence of kanamycin demonstrated a 1:15 Mendelian segregation of both transgenes among seedlings of the T1 progeny of two plants from one transgenic L. latifolia line.

Agrobacterium -mediated transformation has been used to introduce the yeast halotolerant HAL2 as well as the npt II and uid A marker genes into tomato ( Lycopersicon esculentum ) cv. UC82B. Five to six percent of the explants produced transgenic plants. HAL2 expressing transformants were allowed to self-pollinate and salt tolerance assays were performed in vitro on progenies from two independent transgenic plants with different levels of expression of the transgene. In vitro salt tolerance was evaluated according to the level of growth of hypocotyl-derived calli as well as the rooting capability of isolated shootlets on MS-modified medium supplemented with NaCl. Under salt stress, callus formation from hypocotyl explants was higher on both transgenic-derived progenies than in the control. In addition, progenies from the plant with the highest expression of the transgene (2H20b), also showed a higher level of root production on NaCl-supplemented medium. These results suggested a positive effect of the yeast HAL2 gene on the level of salt tolerance in progenies derived from transgenic plants.

Glioblastoma (GBM), the most common primary malignant brain tumor in adults, lacks effective long-term treatment. The tumor is dependent on neovascularization for survival, making angiogenesis an attractive target for therapeutic intervention. The exact mechanism underlying the effects of antiangiogenic agents on GBM remains debatable, although it likely involves vascular endothelial growth factor (VEGF), and other proangiogenic growth factors. Early studies in the recurrent GBM setting were promising and prompted two multinational randomized phase three trials (AVAglio and RTOG 0825) investigating the effect of bevacizumab, an anti-VEGF monoclonal antibody, in newly diagnosed GBM.In this article, the authors discuss the basic mechanisms of angiogenesis and antiangiogenic resistance. The authors additionally summarize the current state of clinical research and how it will impact both future research and the development antiangiogenic therapies.The ultimate utility of antiangiogenic therapy in the management of GBM remains unclear. In an effort to improve outcomes, there remains an urgent need to better understand the biology underlying angiogenesis and tumor survival, as well as mechanisms of antiangiogeneic resistance. Ultimately, combinatorial approaches using antiangiogenic agents, targeted molecular therapy, immunotherapy or cytotoxics may be needed to improve treatment outcomes.

ONC201 is a first-in-class small molecule discovered in a phenotypic screen for p53-independent inducers of tumor-selective pro-apoptotic pathways. Oral ONC201 is currently being evaluated at leading institutions as a new therapeutic agent in five early phase clinical trials for select advanced cancers based on pronounced efficacy in aggressive and refractory tumors and excellent safety. Here, we report the prediction and validation of selective direct molecular interactions between ONC201 and specific members of the dopamine receptor family. One initial prediction of this interaction was derived from the BANDIT drug target prediction method. BANDIT combines millions of data points from clinical, genomic, chemical and structural datasets within a Bayesian network to predict the targets of small molecules. The molecular structure of ONC201, its in vitro efficacy profile, and its publicly available bioactivity assay results were used as inputs for BANDIT and ONC201 was tested against all small molecules with known targets. Results of the BANDIT analysis indicated that ONC201 was highly correlated with other small molecules known to target DRD2, a member of the dopamine receptor family of GPCRs. Furthermore, BANDIT predicted a highly specific binding to DRD2 rather than other members of the dopamine receptor family. In parallel to these independent in silico predictions, experimental GPCR profiling indicated that ONC201 selectively antagonizes the D2-like, but not D1-like, subfamily of dopamine receptors. Reporter assays in a heterologous expression system revealed that ONC201 selectively antagonizes both short and long isoforms of DRD2 and DRD3, with weaker potency for DRD4 and no antagonism of DRD1 or DRD5. Increased secretion of prolactin is a clinical hallmark of DRD2 antagonism by several psychiatric medications that potently target this receptor. ELISA measurements in the peripheral blood of patients who were treated with ONC201 in the first-in-human trial with advanced solid tumors determined that 10/11 patients evaluated in this analysis exhibited induction of prolactin (mean of 2-fold). Using the TCGA database, we found that the D2-like subfamily of dopamine receptors, particularly DRD2, is prevalent and selectively overexpressed in several malignancies. Preclinical reports show that DRD2 inhibition imparts antitumor efficacy, without killing normal cells, via induction of ATF4/CHOP and inhibition of Akt and ERK signaling that are all attributes of ONC201. In summary, antagonizing the D2-like family of dopamine receptors appears to be a promising therapeutic target in oncology, and ONC201 is the first compound to exploit this treatment paradigm in several ongoing Phase II clinical studies. Citation Format: Neel S. Madhukar, Olivier Elemento, Cyril H. Benes, Mathew J. Garnett, Mark Stein, Joseph R. Bertino, Howard L. Kaufman, Isabel Arrillaga-Romany, Tracy T. Batchelor, Lee Schalop, Wolfgang Oster, Martin Stogniew, Michael Andreeff, Wafik S. El-Deiry, Joshua E. Allen. D2-like dopamine receptor antagonism by ONC201 identified by confluence of computational, receptor binding, and clinical studies. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-209.

The purpose of this article is to review neurologic complications associated with systemic anticancer therapies.Although neurologic complications from traditional chemotherapies are well described, most neurologists are less familiar with complications from agents that target specific pathways or receptors. This article also reviews the most common neurologic adverse effects associated with newer targeted agents.Patients with cancer are living longer because of earlier diagnoses and remarkable improvements in treatments. Unfortunately, both traditional chemotherapies and newer targeted agents are known to cause neurologic symptoms that can impact quality of life and play a role in limiting potential treatments. Acute, subacute, and chronic syndromes may affect the central or peripheral nervous system. Since treatments for therapy-induced neurotoxicity are limited, awareness of common neurologic complications is important to prevent permanent damage.

Reverse genetics, defined as ectopic candidate gene expression or silencing, has become an indispensable tool for functional dissection of traits of interest in forest trees. In maritime pine as in other conifers, long generation time and long life span, high genetic loads as well as high genetic redundancy are major obstacles to perform standard genetic approaches including association genetics. Validating marker associations with specific properties before transferring into breeding selection models is still challenging. Stable Agrobacterium-mediated genetic transformation of maritime pine was first reported by Trontin et al. (2002) and developed in both France (FCBA, INRA) and Portugal (IBET) with sufficient refinement (reviewed in Trontin et al. 2007) to envisage practical application in reverse genetics as an attractive alternative to association studies. As a result, the technology has been recently implemented in French (GenoQB, 2006-2009) and transnational (Sustainpine, 2010-2013) or European initiatives (ProCoGen 2012-2016). Somatic embryogenesis (SE) was revealed as a key tissue culture system for achieving genetic transformation, easy cryopreservation of transgenic tissue and efficient transgenic plant regeneration in maritime pine. Much consideration is given in France, Portugal and Spain to apply SE as a clonal propagation system for maritime pine improvement and deployment strategies in multivarietal forestry (MVF, Park YS, reviewed in Klimaszewska et al. 2007). By using this technology it is expected that we will obtain greater genetic gain, high flexibility in deployment of tested embryogenic varieties and easy balancing of genetic gain and diversity in plantations. Both SE and Agrobacterium-mediated transformation methods developed at FCBA, INRA or IBET are being successfully transferred to different partners through running the Sustainpine project (http://www.scbi.uma.es/sustainpine/).

A protocol to achieve efficient plant regeneration from juvenile black locust (Robinia pseudoacacia L.) explants is described. Direct adventitious shoots were induced from cotyledon explants on woody plant medium containing 22.2 μm BA and 0.4 μm 2,4-D. Shoots developed and new shoots were induced when the explants were transferred to medium without growth regulators. The effect of dark incubation on shoot regeneration from cotyledons indicated that 15 days of darkness resulted in a high regeneration frequency (91.7%). Adventitious shoot formation also was induced from sections of in vitro-derived leaves cultured in darkness on Murashige and Skoog medium supplemented with 4.4 μm BA and 24.6 μm IBA. A shoot regeneration frequency of 89% was obtained when explants were subcultured on a medium containing 4.4 μm BA and 0.5 μm IAA. Shoots were rooted on Schenk and Hildebrandt medium with or without IBA. Plantlets were acclimatized and grown in the greenhouse. Chemical names used: N -(phenylmethyl)-1H -purin-6-amine (BA); 2,4-dichlorophenoxyacetic acid (2,4-D); indole-3-acetic acid (IAA); indole-3-butyric acid (IBA).

Modafinil differs from other arousal-enhancing agents in chemical structure, neurochemical profile, and behavioral effects. Most functional neuroimaging studies to date examined the effect of modafinil only on information processing underlying executive cognition, but cognitive enhancers in general have been shown to have pronounced effects on emotional behavior, too. We examined the effect of modafinil on neural circuits underlying affective processing and cognitive functions. Healthy volunteers were enrolled in this double-blinded placebo-controlled trial (100 mg/day for 7 days). They underwent BOLD fMRI while performing an emotion information-processing task that activates the amygdala and two prefrontally dependent cognitive tasks—a working memory (WM) task and a variable attentional control (VAC) task. A clinical assessment that included measurement of blood pressure, heart rate, the Hamilton anxiety scale, and the profile of mood state (POMS) questionnaire was also performed on each test day. BOLD fMRI revealed significantly decreased amygdala reactivity to fearful stimuli on modafinil compared with the placebo condition. During executive cognition tasks, a WM task and a VAC task, modafinil reduced BOLD signal in the prefrontal cortex and anterior cingulate. Although not statistically significant, there were trends for reduced anxiety, for decreased fatigue-inertia and increased vigor-activity, as well as decreased anger-hostility on modafinil. Modafinil in low doses has a unique physiologic profile compared with stimulant drugs: it enhances the efficiency of prefrontal cortical cognitive information processing, while dampening reactivity to threatening stimuli in the amygdala, a brain region implicated in anxiety.

Successful propagation of seedlings and mature trees of Sorbus domestica L. has been achieved by in vitro methods. Multiple shoot formation was obtained by placing shoot apices or nodal segments on a modified Schenck and Hildebrandt medium containing benzyladenine. Regenerated shoots were excised and induced to root on media with auxin. In the best treatments 75–85% of shoots from juvenile material rooted. Rooting capacity of shoots from mature explants was lower (30%) and was not improved by dipping the base of shoots in concentration solutions of indolebutyric or naphthaleneacetic acids. Plantlets were ultimately established in soil.

Social defeat stress is a salient stressor that induces neuroadaptive changes in the mesocorticolimbic dopaminergic system. Substantial evidence indicates that mu-opioid receptors (MORs) modulate dopamine transmission in the ventral tegmental area (VTA). FosB/DeltaFosB protein accumulation in dopaminergic projections during repeated treatments is thought to be involved in long-term neuroplasticity. In this study we characterize the magnitude and time-course of MOR mRNA expression and FosB/DeltaFosB immunoreactivity in mesocorticolimbic regions following repeated social defeat stress. Effects of brief repeated social defeat stress or control handling procedures were studied in rats either 2 h after the last exposure, or 3, 7, 14, 21 and 28 days later. We found that MOR mRNA expression in the VTA doubled after the last stress compared with handling, and remained 30-70% higher until day 21. The number of FosB/DeltaFosB-labeled neurons in regions of the frontal cortex, nucleus accumbens (NAc) shell and core, and in the medial, central and basolateral amygdala increased significantly immediately after the last stress episode, and remained enhanced for 21 days. Another group of rats received bilateral intra-VTA infusion of the MOR agonist, DAMGO, 7 days after the last stress. Prior social defeat stress augmented DAMGO-induced Fos expression in the NAc shell, suggesting that Fos expression in this region might be the direct result of MOR activity in the VTA. Social defeat stress leads to an increased capacity for MOR activation in the VTA, which may be relevant to enduring FosB/DeltaFosB expression in mesocorticolimbic areas and to the behaviorally sensitized response to psychostimulant drugs.

We generated transgenic spike lavender (Lavandula latifolia) plants constitutively expressing the limonene synthase (LS) gene from spearmint (Mentha spicata), encoding the LS enzyme that catalyzes the synthesis of limonene from geranyl diphosphate. Overexpression of the LS transgene did not consistently affect monoterpene profile in pooled leaves or flowers from transgenic T(0) plants. Analyses from cohorts of leaves sampled at different developmental stages showed that essential oil accumulation in transgenic and control plants was higher in developing than in mature leaves. Furthermore, developing leaves of transgenic plants contained increased limonene contents (more than 450% increase compared to controls) that correlated with the highest transcript accumulation of the LS gene. The levels of other monoterpene pathway components were also significantly altered. T(0) transgenic plants were grown for 2 years, self-pollinated, and the T(1) seeds obtained. The increased limonene phenotype was maintained in the progenies that inherited the LS transgene.

Essential oil yield and composition in seven natural populations of Lavandula latifolia from the eastern Iberian Peninsula were determined by GC/MS. Twenty-eight constituents were identified, accounting for 92.0e95.4% of the total oils. These oils were dominated by the monoterpene fraction and three of them (linalool, cineole and camphor) constituted 79.5e86.9% of the oil from flowers. Essential oil yield in leaves and flowers varied among and within populations, but hierarchic analyses of variance showed that the proportion of variation attributable to individuals was significantly higher than that attributable to population differences. Principal component and cluster analyses allowed three groups of flower essential oils to be distinguished according to their high, intermediate and low proportion of linalool. These essential oil types are respectively correlated to the Supra-, Meso- and Thermo-Mediterranean bioclimatic belts where the populations are located. A genetic analysis based on those terpenes that showed a trimodal distribution roughly corroborated the relationships between the seven populations obtained from the ordination analyses and emphasizes the distinctiveness of some of the populations. 2007 Elsevier Ltd. All rights reserved.

BACKGROUND: Prior to 2012 there was no standardized admission protocol at our institution for patients presenting with a single brain mass. The service to which they were admitted, specialty consultations requested, and diagnostic testing employed varied significantly, both in the emergency department and on the inpatient services. In order to enhance management of this patient population we created and implemented a Single Brain Mass admission protocol. Our goal was to provide specialized care from a single multidisciplinary team from admission to discharge, reduce length of hospitalization, limit unnecessary diagnostic testing, and enhance patient care. METHODS: We reviewed records of 94 patients without a cancer history admitted to our emergency department with a new single brain mass between 12/2010 - 08/2014. Patients admitted prior to the protocol implementation (11/2012) were designated the pre-intervention group (PRE), and those admitted following implementation comprised the post-intervention group (POST). RESULTS: 46 patients were PRE and 48 were POST. When patients discharged to rehabilitation (35/94) were excluded from the analysis, a significantly longer mean length of stay was noted in the PRE compared to POST group (7.37 days versus 4.6 days; P= 0.01). More patients underwent CT scans of the chest, abdomen or pelvis in the PRE compared to the POST group (49% versus 17%, P = 0.001). There was no significant difference in the number of patients discharged to a rehabilitation center (38% in PRE vs. 35% in POST) or diagnosed with a brain metastasis (0.04% for both groups). Length of stay in the emergency room and time to surgery was similar across groups. CONCLUSION: Implementation of a management protocol executed by a single, specialized, multidisciplinary team streamlined the care of patients with a new single brain mass, decreased their average length of stay and reduced unnecessary diagnostic imaging tests.

We developed procedures for slow-growth storage of Cedrus atlantica and Cedrus libani microcuttings of juvenile and adult origin, noting factors favouring the extension of subculture intervals. Microcuttings could be stored effectively up to 6 months at 4 degrees C and reduced light intensity, provided that they were grown on a diluted modified MS medium. The addition of 6% mannitol to the storage media affected negatively survival and multiplication capacity of the cultures. The slow-growth storage conditions used in our experiments did not induce remarkable effects on both RAPD variability and average DNA methylation in the species.

We developed procedures for in vitro cloning of Cedrus atlantica Manetti and C. libani A. Rich explants from juvenile and mature plants. Explant size was one determinant of the frequency of axillary bud break in both species. Shoot tips and nodal explants mainly developed calli, whereas bud sprouting occurred in defoliated microcuttings cultured on a modified Murashige and Skoog medium without growth regulators. Isolation and continuous subculture of sprouted buds on the same medium allowed cloning of microcuttings from C. atlantica and C. libani seedlings and bicentennial C. libani trees, thus providing a desirable alternative for multiplying mature trees that have demonstrated superior characteristics. We also report adventitious bud differentiation from isolated embryos of C. atlantica. Neither auxin treatments nor other methods tested, including infection with Agrobacterium rhizogenes, were effective in inducing root initiation.

A repeatable transformation system has been established for Digitalis minor using Agrobacterium tumefaciens. Leaf explants from 30-day-old seedlings were inoculated with either EHA105 (carrying the nptII and gusA genes) or AGL1 (with the bar and gusA genes) strains. Among the tested factors influencing T-DNA transfer to plants, the EHA105 strain and the addition of acetosyringone to the co-culture medium increased transformation. The highest transformation efficiency (8.4%) was obtained when freshly isolated explants, soaked in a bacterial suspension with an OD 550 of 0.9, were subcultured on selection medium after a 4-day co-culture with the bacteria. Evidence of stable transgene integration was obtained by PCR, growth on media selective for nptll or bar genes, and expression of the gusA gene. Southern hybridisation, performed in six plants, provided information about the number of inserts. More than 200 transgenic plants were recovered from 65 independent explants. Thirty of these plants were successfully established in soil. This is the first report on transgenic Digitalis spp plants using an A. tumefaciens-mediated leaf disc transformation procedure.

Shoot-tips from several genotypes of the cardenolide-producing perennial shrub Digitalis obscura L. were successfully cryopreserved using the encapsulation-dehydration technique. Precultivation on MS medium containing 0.5 M sucrose, followed by 2.5 h dehydration (final weight 30 %) induced shoot regrowth in 42 % of cryopreserved shoot-tips. Cold-hardening of the in vitro cultures before sucrose treatment dramatically increased shoot recovery up to 86 %. The optimized cryopreservation protocol was then employed using different shoot cultures from five D. obscura genotypes. Responses to cryopreservation depended mainly on the genotype, best results being obtained when shoot tips from HU3 and LL11 were used. Prolonged subcultures reduced proliferation rates in both control and cryopreserved HU3 shoot-tips, whereas long-term storage in LN did not affect the shoot recovery rate of the genotype. RAPD markers were employed to evaluate possible somaclonal variation occurring in shoots regenerated through successive subcultures and after cryopreservation. The band patterns revealed differences between the original parent plant and the shoots grown in vitro, especially after a prolonged subculture (84.9 % of matches for HU3 after 16 subcultures vs. 93.4 % for AY3 after 2 subcultures). Nevertheless, match percentages were higher (98.6 % to 99.5 %) when band patterns from subcultured shoots were compared to those obtained from their respective control or frozen progenies indicating that cryopreservation ensure genetic stability of selected Digitalis obscura genotypes.