No abstract

Fungal infections and toxicoses caused by insecticides may alter microbial communities and immune responses in the insect gut. We investigated the effects of Metarhizium robertsii fungus and avermectins on the midgut physiology of Colorado potato beetle larvae. We analyzed changes in the bacterial community, immunity- and stress-related gene expression, reactive oxygen species (ROS) production, and detoxification enzyme activity in response to topical infection with the M. robertsii fungus, oral administration of avermectins, and a combination of the two treatments. Avermectin treatment led to a reduction in microbiota diversity and an enhancement in the abundance of enterobacteria, and these changes were followed by the downregulation of Stat and Hsp90, upregulation of transcription factors for the Toll and IMD pathways and activation of detoxification enzymes. Fungal infection also led to a decrease in microbiota diversity, although the changes in community structure were not significant, except for the enhancement of Serratia. Fungal infection decreased the production of ROS but did not affect the gene expression of the immune pathways. In the combined treatment, fungal infection inhibited the activation of detoxification enzymes and prevented the downregulation of the JAK-STAT pathway caused by avermectins. The results of this study suggest that fungal infection modulates physiological responses to avermectins and that fungal infection may increase avermectin toxicosis by blocking detoxification enzymes in the gut.

No abstract

The study has demonstrated a dual effect of nitric oxide on phenoloxidase (PO)-mediated DOPA oxidation and melanization process. NO generated at low rates proportionally increased in PO-mediated DOPA oxidation. Competitive PO inhibitor, phenylthiourea, resulted in significant inhibition of NO-mediated DOPA oxidation. Further analysis using fluorescent and EPR methods demonstrated that the effect of NO on DOPA oxidation is explained by oxidation of NO to NO 2 at the active site of PO followed by oxidation of DOPA by NO 2 . On the contrary, the bolus addition of NO gas solution resulted in a significant decrease in observed PO activity. Similar dose-dependent effect of NO was observed for the insect's haemocytes quantified as percentage of melanized cells after treatment with nitric oxide. In conclusion, the results of the study suggest that NO may have a significant regulatory role on melanization process in invertebrates as well as in human and result in protective or damaging effects.

No abstract

An isolate of the microsporidium Vairimorpha ephestiae (originally isolated from Ephestia kühniella) from collection of Prof. J. Weiser was propagated in a laboratory culture of Galleria mellonella. Only disporoblastic sporogony was observed and formation of octospores, characteristic of the genus Vairimorpha, never occurred. A partial nucleotide sequence of the small subunit rRNA gene (1247 bp) for this microsporidium showed 100% identity to the homologous sequences of Vairimorpha (Nosema) necatrix (Genbank accession # U11051 and # DQ996241), a microsporidium with a broad host range within the Lepidoptera. Sequence similarity of protein-coding genes (RPB1, HSP70 and actin) between V. ephestiae and V. necatrix was about 98-100%. The level of genetic polymorphism in the RPB1 locus between these two species was essentially the same as between isolates of V. necatrix. It is therefore concluded that V. ephestiae is in fact an isolate of V. necatrix and the former species should be synonymized with the latter. Though described later, V. necatrix has prevailing usage and its precedence over V. ephestiae is proposed to conserve stability and avoid confusion.

Personalized medicine often serves as the first salvage therapy strategy when standard oncology treatments fail. However, most precision oncology approaches rely on molecular profiling which, unfortunately, provides therapeutic options for less than 10% of cancer patients. Functional precision medicine (FPM) complements molecular profiling by combining it with rapid, high-throughput drug testing on live patient cells to identify promising treatment options. In this study, we investigated the efficacy of FPM in the management of pediatric patients with recurrent and/or refractory cancers. We enrolled 25 pediatric/young adult patients with refractory solid or liquid cancers in this clinical trial (number NCT03860376). Enrolled patients represented the breadth of cancer indications generally presenting in pediatric patients: acute lymphoblastic leukemia (3 patients), acute myeloid leukemia (3 patients), astrocytoma (1 patient), ependymoma (1 patient), Ewing’s sarcoma (4 patients), glioblastoma (1 patient), malignant rhabdoid tumor (1 patient), medulloblastoma (1 patient), neuroblastoma (1 patient), osteosarcoma (4 patients), rhabdomyosarcoma (4 patients) and Wilms’ tumor (1 patient). We used a functional ex vivo drug sensitivity test (DST) panel encompassing 40 formulary drugs frequently used at Nicklaus Children’s Hospital and 47 non-formulary drugs approved by FDA for cancer treatment, as well as drugs from phase III and IV clinical trials. Drug sensitivity scores (DSS) were calculated for each drug based on cancer cells’ responses. DST results were then combined with results from targeted mutation profiles to match actionable mutations with selective targeted therapies. FPM and molecular data were prospectively generated and treatment recommendations were provided to an FPM Molecular Tumor Board (MTB) of clinicians. In total, 19 of 25 patients (76%) had complete functional and molecular profiling data provided to the MTB to support clinical decision-making. Six patients had their subsequent treatment guided by FPM recommendations, of which 83% (five of six patients) demonstrated greater than 1.3x increased progression-free survival compared to their previous therapy. Interestingly, hierarchical clustering analysis of DST results shows that patients with the same subtype of cancer do not cluster together, and no cancer subtype is differentially represented in either high-level cluster, suggesting the importance of functional profiling to provide deeper insight into individual patient pharmacological response. This FPM study is the first pediatric cancer study to enroll both solid and hematologic cancers regardless of tumor type, and the first FPM study in the United States to generate prospective treatment data on pediatric oncology patients. We illustrate the feasibility and efficacy of FPM to meet the needs of cancer patients with both liquid and solid tumors, especially for high-risk populations such as pediatric cancer patients. Citation Format: Arlet Maria Acanda de la Rocha, Maggie Fader, Ebony R. Coats, Joseph Dunn, Leat Perez, Carolina Velasquez, Jeanette Galano, Cima Saghira, Ileana Sotto, Yana Vorontsova, Ziad Khatib, Haneen Abdella, Cristina M. Andrade-Feraud, Alexa Jacome, Victoria Reis, Lilliam Rimblas, Nicole Tomas, Paula S. Espinal, Noah Berlow, Tomás R. Guilarte, Jennifer McCafferty-Fernandez, Daria Salyakina, Diana J. Azzam. Efficacy of a functional precision medicine approach in relapsed/refractory pediatric cancer patients: results from a prospective clinical study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB358.