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The volcano rabbit ( Romerolagus diazi ) is a lagomorph endemic to the central mountains of the Trans-Mexican Volcanic Belt and is classified as threatened at extinction risk. It is a habitat specialist in bunchgrass communities. The annual wildfires that occur throughout its distribution range are a vulnerability factor for the species. However, the effects of wildfires on volcano rabbit populations are not fully understood. We evaluated the occupancy and change in the volcano rabbit relative abundance index in the burned bunchgrass communities of the Ajusco-Chichinautzin Mountain Range during an annual cycle of wildfire events. Additionally, we assessed the factors that favor and limit occupation and reoccupation by the volcano rabbit using the relative abundance index in burned plots as an indicator of these processes. The explanatory factors for the response of the volcano rabbit were its presence in the nearby unburned bunchgrasses, the height of three species of bunchgrass communities, the proportion of different types of vegetation cover within a 500 m radius around the burned plots, heterogeneity of the vegetation cover, and the extent of the wildfire. Statistical analyses indicated possible reoccupation in less than a year in burned bunchgrass communities adjacent to unburned bunchgrass communities with volcano rabbits. The relative abundance index of volcano rabbits was not favored when the maximum height of the Muhlenbergia macroura bunchgrass community was less than 0.77 m. When the vegetation around the burned plots was dominated by forest (cover >30% of the buffer) and the fire was extensive, the number of latrines decreased per month but increased when the bunchgrass and shrub cover was greater around the burned plots. While the statistical results are not conclusive, our findings indicate a direction for future projects, considering extensive monitoring to obtain a greater number of samples that contribute to consolidating the models presented., Competing Interests: This research is part of the Doctoral dissertation of Juan Manuel Uriostegui Velarde (CONACyT scholarship 281981) presented at the Instituto de Ecología, A. C., (© 2024 Uriostegui-Velarde et al.)

Peroxiredoxin 6 (Prdx6) repairs peroxidized membranes by reducing oxidized phospholipids, and by replacing oxidized sn-2 fatty acyl groups through hydrolysis/reacylation by its phospholipase A 2 (aiPLA 2 ) and lysophosphatidylcholine acyltransferase activities. Prdx6 is highly expressed in the lung, and intact lungs and cells null for Prdx6 or with single-point mutations that inactivate either Prdx6-peroxidase or aiPLA 2 activity alone exhibit decreased viability, increased lipid peroxidation, and incomplete repair when exposed to paraquat, hyperoxia, or organic peroxides. Ferroptosis is form of cell death driven by the accumulation of phospholipid hydroperoxides. We studied the role of Prdx6 as a ferroptosis suppressor in the lung. We first compared the expression Prdx6 and glutathione peroxidase 4 (GPx4) and visualized Prdx6 and GPx4 within the lung. Lung Prdx6 mRNA levels were five times higher than GPx4 levels. Both Prdx6 and GPx4 localized to epithelial and endothelial cells. Prdx6 knockout or knockdown sensitized lung endothelial cells to erastin-induced ferroptosis. Cells with genetic inactivation of either aiPLA 2 or Prdx6-peroxidase were more sensitive to ferroptosis than WT cells, but less sensitive than KO cells. We then conducted RNA-seq analyses in Prdx6-depleted cells to further explore how the loss of Prdx6 sensitizes lung endothelial cells to ferroptosis. Prdx6 KD upregulated transcriptional signatures associated with selenoamino acid metabolism and mitochondrial function. Accordingly, Prdx6 deficiency blunted mitochondrial function and increased GPx4 abundance whereas GPx4 KD had the opposite effect on Prdx6. Moreover, we detected Prdx6 and GPx4 interactions in intact cells, suggesting that both enzymes cooperate to suppress lipid peroxidation. Notably, Prdx6-depleted cells remained sensitive to erastin-induced ferroptosis despite the compensatory increase in GPx4. These results show that Prdx6 suppresses ferroptosis in lung endothelial cells and that both aiPLA 2 and Prdx6-peroxidase contribute to this effect. These results also show that Prdx6 supports mitochondrial function and modulates several coordinated cytoprotective pathways in the pulmonary endothelium., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jose Pablo Vazquez-Medina reports financial support was provided by National Institute of General Medical Sciences. Jose Pablo Vazquez-Medina reports a relationship with National Institute of General Medical Sciences that includes: funding grants. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Elephant seals exhibit extreme hypoxemic tolerance derived from repetitive hypoxia/reoxygenation episodes they experience during diving bouts. Real-time assessment of the molecular changes underlying protection against hypoxic injury in seals remains restricted by their at-sea inaccessibility. Hence, we developed a proliferative arterial endothelial cell culture model from elephant seals and used RNA-seq, functional assays, and confocal microscopy to assess the molecular response to prolonged hypoxia., Results: Seal and human endothelial cells exposed to 1% O 2 for up to 6 h respond differently to acute and prolonged hypoxia. Seal cells decouple stabilization of the hypoxia-sensitive transcriptional regulator HIF-1α from angiogenic signaling. Rapid upregulation of genes involved in glutathione (GSH) metabolism supports the maintenance of GSH pools, and intracellular succinate increases in seal but not human cells. High maximal and spare respiratory capacity in seal cells after hypoxia exposure occurs in concert with increasing mitochondrial branch length and independent from major changes in extracellular acidification rate, suggesting that seal cells recover oxidative metabolism without significant glycolytic dependency after hypoxia exposure., Conclusions: We found that the glutathione antioxidant system is upregulated in seal endothelial cells during hypoxia, while this system remains static in comparable human cells. Furthermore, we found that in contrast to human cells, hypoxia exposure rapidly activates HIF-1 in seal cells, but this response is decoupled from the canonical angiogenesis pathway. These results highlight the unique mechanisms that confer extraordinary tolerance to limited oxygen availability in a champion diving mammal., (© 2024. The Author(s).)

Elephant seals experience natural periods of prolonged food deprivation while breeding, molting, and undergoing postnatal development. Prolonged food deprivation in elephant seals increases circulating glucocorticoids without inducing muscle atrophy, but the cellular mechanisms that allow elephant seals to cope with such conditions remain elusive. We generated a cellular model and conducted transcriptomic, metabolic, and morphological analyses to study how seal cells adapt to sustained glucocorticoid exposure. Seal muscle progenitor cells differentiate into contractile myotubes with a distinctive morphology, gene expression profile, and metabolic phenotype. Exposure to dexamethasone at three ascending concentrations for 48 h modulated the expression of six clusters of genes related to structural constituents of muscle and pathways associated with energy metabolism and cell survival. Knockdown of the glucocorticoid receptor (GR) and downstream expression analyses corroborated that GR mediates the observed effects. Dexamethasone also decreased cellular respiration, shifted the metabolic phenotype toward glycolysis, and induced mitochondrial fission and dissociation of mitochondria-endoplasmic reticulum (ER) interactions without decreasing cell viability. Knockdown of DNA damage-inducible transcript 4 (DDIT4), a GR target involved in the dissociation of mitochondria-ER membranes, recovered respiration and modulated antioxidant gene expression in myotubes treated with dexamethasone. These results show that adaptation to sustained glucocorticoid exposure in elephant seal myotubes involves a metabolic shift toward glycolysis, which is supported by alterations in mitochondrial morphology and a reduction in mitochondria-ER interactions, resulting in decreased respiration without compromising cell survival.

Marine mammals exhibit some of the most dramatic physiological adaptations in their clade and offer unparalleled insights into the mechanisms driving convergent evolution on relatively short time scales. Some of these adaptations, such as extreme tolerance to hypoxia and prolonged food deprivation, are uncommon among most terrestrial mammals and challenge established metabolic principles of supply and demand balance. Non-targeted omics studies are starting to uncover the genetic foundations of such adaptations, but tools for testing functional significance in these animals are currently lacking. Cellular modeling with primary cells represents a powerful approach for elucidating the molecular etiology of physiological adaptation, a critical step in accelerating genome-to-phenome studies in organisms in which transgenesis is impossible (e.g., large-bodied, long-lived, fully aquatic, federally protected species). Gene perturbation studies in primary cells can directly evaluate whether specific mutations, gene loss, or duplication confer functional advantages such as hypoxia or stress tolerance in marine mammals. Here, we summarize how genetic and pharmacological manipulation approaches in primary cells have advanced mechanistic investigations in other non-traditional mammalian species, and highlight the need for such investigations in marine mammals. We also provide key considerations for isolating, culturing, and conducting experiments with marine mammal cells under conditions that mimic in vivo states. We propose that primary cell culture is a critical tool for conducting functional mechanistic studies (e.g., gene knockdown, over-expression, or editing) that can provide the missing link between genome- and organismal-level understanding of physiological adaptations in marine mammals., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.)

Purpose: We performed a cross-sectional study of neurocognitive function in non-brain cancer patients treated with long-term bevacizumab., Methods/patients: From 2015 to 2017, we included patients with different types of cancer treated with bevacizumab with or without chemotherapy (BEV; N = 20) or only chemotherapy (ChT; N = 19) for at least 34 weeks, patients who received non-brain radiotherapy (RxT; N = 19), and healthy controls (HC; N = 19) were assessed once at week 34 of treatment (BEV and ChT) or at completion of radiotherapy. Neurocognition was evaluated with the Hopkins Verbal Learning Test-Revised (HVLT-R) total and delayed recall, the Trail Making Test A and B, and the Controlled Oral Word Association Test in the four groups. Non-parametric tests were used to assess differences between groups., Results: The BEV, ChT, and RxT groups scored significantly lower than the HC group on all tests and especially on the HVLT-R total recall. In no case were the mean scores of the BEV group significantly lower than those of the ChT or RxT groups., Conclusions: Neurocognitive impairment was seen even in patients treated with local non-brain radiotherapy. Treatment with bevacizumab for a long period of time does not seem to worsen neurocognitive function to a greater extent than chemotherapy.

Background: Immune-oncology agents (IOA) represent a turning point in the treatment of several solid tumors (ST). Although their toxicity compares favorably with other treatments, IOA associate immune-related adverse events (IR-AE), among which endocrine-related AE stand out. We retrospectively evaluated the occurrence of endocrine (E) IR-AE in a cohort of patients with several ST treated with IOA. In addition, we assessed the correlation between likelihood of survival and the occurrence of IR-AE., Methods: We collected data on clinical and molecular characteristics, efficacy and AE of 260 patients with ST treated with IOA from 2013 to 2017. We excluded patients with prior conditions or treatments potentially affecting thyroid test results., Results: Lung cancer was the most prevalent diagnosis (70.2%). EIR-AE appeared in 18.1% of patients (total of 38 EIR-AE) and consisted of hypothyroidism, hyperthyroidism, pituitary disorders and type 1 diabetes mellitus in 60.5%, 21.1%, 15.8% and 2.6% of patients, respectively. EIR-AE were associated mainly to nivolumab, nivolumab plus ipilimumab (41.2% and 26.5%) and appeared after a median of 4.2 cycles of treatment. Specific therapy was required in 65.8% patients. There were significant differences in both progression-free survival (PFS) and overall survival (OS) for patients who experienced EIR-AE compared to those who did not [PFS: 56.7 (NC-NC) vs. 27.7 (14.3-41.3) months, P=0.008; OS: NC (NC-NC) vs. 31.4 (20.7-42.1) months, P=0.001]., Conclusions: The incidence of EIR-AE in our study is similar to other series. Patients who develop EIR-AE might have a better prognosis compared to those who do not experience them., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare., (2020 Translational Lung Cancer Research. All rights reserved.)

Background/Context: Glioblastoma (GB) is the most common primary brain tumour in adults and it is associated with a high mortality rate. According to the stem cell theory, the growth, relapse and treatment response of GB is determined by the stem cell subpopulation present in the tumour. Objective: Our aim is to study the prognostic value of stem cell markers (CD44, Nestin, Olig2 and SOX2) in a series of homogeneously treated GBs. Material and methods: We study 280 GBs treated with STUPP acheme with a histologican review of the cases and TMA with a máximum of 4 spots for each case. Each slide was immunohistochemically stained and Reading. We compared the immunohistochemical results with survival tme. Results: Only SOX2 immunoexpression (IE) excedding 10% of the tumour cells was found to be related to good survival (p= 0.037) in univariate analysis. However, amultivariate analysis indicate the age, surgery and MGMT promotes methylation but no SOX2 IE are prognostic factors. Conclusions: We conclude the immunohistochemical studies of stem cell markers in GB are not useful for predicting prognosis in daily practice.

T-DM1 is an antibody drug conjugate that combines trastuzumab with emtansine via a stable thioether linker. In two phase III clinical trials, EMILIA and TH3RESA, T-DM1 was shown to be effective in HER2-positive metastatic breast cancer patients who had progressed to taxanes and trastuzumab. We have performed a real-world study to complement the findings of the clinical trials. From 2012 to 2016, 15 patients with HER2-positive breast cancer who had progressed to prior treatment received T-DM1 at our center. We have retrospectively analyzed outcomes in these patients and compared our findings with those of the two clinical trials. Progression-free survival (PFS) was 10 months compared with the 9.6 months of the EMILIA trial and the 6.2 months of the TH3RESA trial, overall survival was 34 months compared with the 29.9 months of the EMILIA trial and the 22.7 months of the TH3RESA trial. PFS was ≥12 months in five patients, three of whom attained a PFS of ≥23 months. Among five patients with metastases of the central nervous system, PFS was six months, OS was not reached, and the objective response rate was 80%. Our findings are in line with those of the EMILIA study and slightly superior to those of the TH3RESA study. In our series of patients, T-DM1 has demonstrated efficacy in the treatment of HER2-positive metastatic breast cancer. Our real-world data thus confirm and support the findings of the two major phase III trials and indicate the usefulness of T-DM1 in routine clinical practice.

Circulating biomarkers in blood may provide an interesting alternative to risky tissue biopsies in the diagnosis and follow-up of glioblastoma patients. We have assessed MGMT methylation status in blood and tissue samples from unresected glioblastoma patients who had been included in the randomized GENOM-009 trial. Paired blood and tissue samples were assessed by methylation-specific PCR (MSP) and pyrosequencing (PYR). After establishing the minimum PYR cut-off that could yield a significant difference in overall survival, we assessed the sensitivity, specificity, positive predictive value and negative predictive value (NPV) of the analyses. Methylation could be detected in cfDNA by both MSP and PYR but with low concordance with results in tissue. Sensitivity was low for both methods (31% and 38%, respectively), while specificity was higher for MSP in blood than for PYR in plasma (96% vs 76%) and NPV was similar (56 vs 57%). Concordance of results in tissue by MSP and PYR was 84.3% (P < 0.001) and correlated with outcome. We conclude that detection of cfDNA in the blood of glioblastoma patients can be an alternative when tumor tissue is not available but methods for the detection of cfDNA in blood must improve before it can replace analysis in tumor tissue.

Background: Second primary malignancies (SPM) in the lung are not common in breast cancer (BC) patients. EGFR-mutant lung cancer (LC) is a separate molecular subset, and the co-existence of EGFR-mutant LC and BC has not been explored. We hypothesized that EGFR-mutant LC patients could have higher rates of primary BC than those with EGFR-wild type (WT)., Methods: We collected data on clinical and molecular characteristics and outcomes of female patients with LC and a previous or simultaneous history of primary BC treated in our hospital from 2008 to 2014., Results: Data on treatment, follow-up, and EGFR mutation status were available for 356 patients. 17.7% (11/62) of patients with EGFR mutations had BC, compared to 1.02% (3/294) of EGFR-WT patients (p < 0.001). Both tumors were metachronous in 81.8%, with LC diagnosed 9 years after the diagnosis of BC. 5 of the 6 (83.3%) BC patients treated with radiotherapy developed LC in an area within the radiation field. No EGFR mutations were detected in BC tissue and no HER2 expression was detected in LC samples., Conclusion: SPM in the lung and breast occur more frequently among EGFR-mutant compared to EGFR-WT LC patients. Radiotherapy for BC may increase the risk of developing primary LC., (© 2019 S. Karger AG, Basel.)

Purpose: We retrospectively examined the potential effect on overall survival (OS) of delaying radiotherapy to administer neoadjuvant therapy in unresected glioblastoma patients., Patients and Methods: We compared OS in 119 patients receiving neoadjuvant therapy followed by standard treatment (NA group) and 96 patients receiving standard treatment without neoadjuvant therapy (NoNA group). The MaxStat package of R identified the optimal cut-off point for waiting time to radiotherapy., Results: OS was similar in the NA and NoNA groups. Median waiting time to radiotherapy after surgery was 13 weeks for the NA group and 4.2 weeks for the NoNA group. The longest OS was attained by patients who started radiotherapy after 12 weeks and the shortest by patients who started radiotherapy within 4 weeks (12.3 vs 6.6 months) (P = 0.05). OS was 6.6 months for patients who started radiotherapy before the optimal cutoff of 6.43 weeks and 19.1 months for those who started after this time (P = 0.005). Patients who completed radiotherapy had longer OS than those who did not, in all 215 patients and in the NA and NoNA groups (P = 0.000). In several multivariate analyses, completing radiotherapy was a universally favorable prognostic factor, while neoadjuvant therapy was never identified as a negative prognostic factor., Conclusion: In our series of unresected patients receiving neoadjuvant treatment, in spite of the delay in starting radiotherapy, OS was not inferior to that of a similar group of patients with no delay in starting radiotherapy.

Background: Osimertinib is efficacious in lung cancer patients with epidermal growth factor receptor ( EGFR ) mutations and acquired resistance (AR) to EGFR tyrosine kinase inhibitors due to EGFR -T790M mutation (T790M). We sought to describe T790M changes in serum/plasma during osimertinib therapy and correlate these changes with treatment outcomes., Material and Methods: Serum/plasma from EGFR -mutant lung cancer patients with T790M-AR was collected before and during osimertinib treatment. Changes in T790M were evaluated using a peptide-nucleic acid-PCR assay, and correlated with clinical and radiographic response., Results: Thirteen patients were included. Median time on osimertinib treatment was 10.6 months with a median progression-free survival of 13.6 months. Best response to osimertinib was partial response (PR), stable disease (SD) or progression (PD) in 46.1%, 30.8% and 23.1% of patients, respectively.Most of the patients were paucisymptomatic at baseline. Symptom improvement was reported in 66.6% of responder patients; while symptoms remained stable in 75% of patients with SD, and 66% of patients with PD had clinical deterioration.Three patterns of T790M changes during osimertinib treatment were identified. T790 remained detectable with PD or a short-lasting SD in 15.4% of the patients. T790M disappeared in 69.2% of patients with PR or SD. T790M disappeared, despite clinical and/or radiographic progression in 15.4% of the patients., Conclusion: Changes of T790M in serum/plasma in EGFR -mutant lung cancer patients with T790M-AR might be a useful marker of symptomatic and radiographic outcome to osimertinib. Longer follow-up is needed to establish if subsequent emergence of T790M could be a marker of resistance., Competing Interests: CONFLICTS OF INTEREST Authors declare no conflicts of interest.

To assess the value of resection in glioblastoma based on pre-surgical tumor characteristics and a subsequent staging system. The lack of a staging system for glioblastoma hinders the analysis of treatment outcome. We classified 292 uniformly treated glioblastoma patients as stage I, II, or III based on tumor size, location, and eloquence and then analyzed the impact of the extent of resection. We classified 62% of patients as stage I, 25.3% as stage II, and 12.7% as stage III. Gross total resection (GTR) was performed mainly in stage I rather than stage II or III patients (79.2% vs. 14.6% vs. 6.3%; P < 0.001). Overall survival (OS) was 17.7, 14.6, and 10.8 months for stage I, II, and III patients, respectively (P = 0.005). Longer OS was significantly associated with greater extent of resection, younger age, KPS ≥ 70%, MGMT methylation, lower stage, and tumor ≤ 5 cm. In the subgroups of stage I (P = 0.04) and stage II (P < 0.001)-but not stage III-patients, GTR and partial resection (PR) were associated with longer OS. We constructed several multivariable models including different variables, and greater extent of resection, smaller tumor size, and MGMT methylation consistently emerged as independent markers of longer OS. This staging system provides a feasible tool for comparison of results. We confirmed the value of partial resection in stage I and II patients, in contrast to some reports suggesting that biopsy only is sufficient when gross total resection cannot be safely achieved.