CD73 mitigates ZEB1 expression in papillary thyroid carcinoma

BACKGROUND

ZEB1, a core transcription factor involved in epithelial-mesenchymal transition (EMT), is associated with aggressive cancer cell behavior, treatment resistance, and poor prognosis across various tumor types. Similarly, the expression and activity of CD73, an ectonucleotidase implicated in adenosine generation, is an important marker of tumor malignancy. Growing evidence suggests that EMT and the adenosinergic pathway are intricately linked and play a pivotal role in cancer development. Therefore, this study focuses on exploring the correlations between CD73 and ZEB1, considering their impact on tumor progression.

METHODS

We employed CRISPR/Cas9 technology to silence CD73 expression in cell lines derived from papillary thyroid carcinoma. These same cells underwent lentiviral transduction of a reporter of ZEB1 non-coding RNA regulation. We conducted studies on cell migration using scratch assays and analyses of cellular speed and polarity. Additionally, we examined ZEB1 reporter expression through flow cytometry and immunocytochemistry, complemented by Western blot analysis for protein quantification. For further insights, we applied gene signatures representing different EMT states in an RNA-seq expression analysis of papillary thyroid carcinoma samples from The Cancer Genome Atlas.

RESULTS

Silencing CD73 expression led to a reduction in ZEB1 non-coding RNA regulation reporter expression in a papillary thyroid carcinoma-derived cell line. Additionally, it also mitigated ZEB1 protein expression. Moreover, the expression of CD73 and ZEB1 was correlated with alterations in cell morphology characteristics crucial for cell migration, promoting an increase in cell polarity index and cell migration speed. RNA-seq analysis revealed higher expression of NT5E (CD73) in samples with BRAF mutations, accompanied by a prevalence of partial-EMT/hybrid state signature expression.

CONCLUSIONS

Collectively, our findings suggest an association between CD73 expression and/or activity and the post-transcriptional regulation of ZEB1 by non-coding RNA, indicating a reduction in its absence. Further investigations are warranted to elucidate the relationship between CD73 and ZEB1, with the potential for targeting them as therapeutic alternatives for cancer treatment in the near future.

Mitochondrial response of glioma cells to temozolomide

Metabolic adaptations are central for carcinogenesis and response to therapy, but little is known about the contribution of mitochondrial dynamics to the response of glioma cells to the standard treatment with temozolomide (TMZ). Glioma cells responded to TMZ with mitochondrial mass increased and the production of round structures of dysfunctional mitochondria. At single-cell level, asymmetric mitosis contributed to the heterogeneity of mitochondrial levels. It affected the fitness of cells in control and treated condition, indicating that the mitochondrial levels are relevant for glioma cell fitness in the presence of TMZ.

The role of mitosis in generating fitness heterogeneity

Cancer cells have heterogeneous fitness, and this heterogeneity stems from genetic and epigenetic sources. Here, we sought to assess the contribution of asymmetric mitosis (AM) and time on the variability of fitness in sister cells. Around one quarter of sisters had differences in fitness, assessed as the intermitotic time (IMT), from 330 to 510 min. Phenotypes related to fitness, such as ERK activity (herein referring to ERK1 and ERK2, also known as MAPK3 and MAPK1, respectively), DNA damage and nuclear morphological phenotypes were also asymmetric at mitosis or turned asymmetric over the course of the cell cycle. The ERK activity of mother cell was found to influence the ERK activity and the IMT of the daughter cells, and cells with ERK asymmetry at mitosis produced more offspring with AMs, suggesting heritability of the AM phenotype for ERK activity. Our findings demonstrate how variabilities in sister cells can be generated, contributing to the phenotype heterogeneities in tumor cells.

Proteomic profile of vitrified in vitro-produced bovine embryos (Bos taurus indicus)

BACKGROUND

The proteomic profile of cryopreserved in vitro produced bovine embryos is little known but can provide insights on the successful application of cryo procedures in support of animal breeding.

OBJECTIVE

To identify embryonic proteins and biomarkers related to improved cryotolerance of vitrified in vitro produced bovine embryos.

MATERIALS AND METHODS

Proteins were isolated from embryo pools (n = 25 embryos per replicate) and analyzed using the nanoLC - MS/MS system. Further, the UniProtKB database (Uniprot -http://www.uniprot.org/) was used for protein identification. Proteins were classified based on their molecular mass, isoelectric point, and enzymatic activity. Post-translational modification predictions and functional gene ontology analysis were performed as well. Finally, a protein-protein interaction network was created to shed light on the embryo interactome.

RESULTS

Based on the MS/MS approach, 66 proteins were identified from vitrified Bos taurus embryos. The retrieved proteins were presumably annotated, which allowed a description of the qualitative and functional aspects of the embryo proteome after the vitrification process.

CONCLUSION

These findings allowed us to conclude that in vitro-produced vitrified embryos expressed proteins that underlie biological processes related to reproduction, stress and lipid metabolic process, which are essential to maintain embryo viability. doi.org/10.54680/fr22410110512.

Abstract 2445: Epigenetic modulation of tumor cell tolerance to chemotherapy

Cancer represents a set of diseases that are dynamic and heterogeneous. Their cells are phenotypically and genetically different from each other and, exhibit stochastic fluctuations in their phenotype. Investigations of isogenic populations of tumor cells reveal that tolerance also may emerge through non-genetic mechanisms, often through stochastic fluctuations in key factors in response to drugs. The objective of this work is to measure the dynamics of chemotherapy tolerance phenotype and modulate these dynamics in tumor cells to potentiate the therapy. Glioma cell lines and primary gliomas were plated at low density and after the formation of colonies, cells were treated with Temozolomide (TMZ) for 3 days. Growth rate of individual colonies was measured and the variance of growth rate of colonies with the same size was used to determine the dynamics of the phenotype. We developed a method to measure the dynamics of phenotype called DynaFit and defined a proportion of phenotypic chance in fitness until generation 6 called rCoDyFF (relative Colony DynaFit Factor 6), which is a value between 0% (stable phenotype) and 100% (dynamic phenotype). The untreated glioma cell lines (U251 and A172) and primary gliomas (LS12 and LS17) had rCoDyFF6 of 40%, 33%, 41%, 33% and treatment with 50uM TMZ produced an rCoDyFF6 67% in U251 cells. However, when cells were treated with a combination of epigenetic modulators and chemotherapy agent, 0.5µM Saha plus 3µM Azacytidine, and 50µM TMZ, the rCoDyFF6 result in - 23%, showing a drastic reduction, indicating stabilization of the phenotype. This treatment also increases sensitivity to TMZ. The result demonstrates that epigenetic modulators were able to induce a phenotypically stable state in U251 cells, leading to the copy of the tolerance phenotype of the colony founder cell to all the cells in the colony. Here we showed tumor cells fluctuate their fitness levels in the absence or presence of chemotherapy and this fluctuations can be stabilized by the inhibition of chromatin and DNA modifying enzymes.

Citation Format: Jephesson Alex Alex dos Santos, Carolina Nunes Santo, Luiza Cherobini Pereira. Epigenetic modulation of tumor cell tolerance to chemotherapy [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 2445.

Apolipoprotein E, periodontal disease and the risk for atherosclerosis: a review

The association between cardiovascular and periodontal diseases is characterized by chronic inflammatory processes, with a high prevalence worldwide and complex genetic-environment interactions. Although apolipoprotein E4 (ApoE4), one of the isoforms coded by a polymorphic APOE gene, has been widely recognized as a risk factor for cardiovascular diseases and as an immunoinflammatory factor, less is known regarding how ApoE4 affects atherosclerosis in periodontitis patients. The aim of this review was to investigate the potential underlying mechanisms related to APOE4 that could increase the risk of periodontal disease and, ultimately, of atherosclerosis. There have only been a few studies addressing apoE polymorphisms in patients with chronic periodontitis. To date, no studies have been performed that have assessed how ApoE4 affects atherosclerotic disease in chronic periodontitis patients. Although clinical studies are warranted, experimental studies have consistently documented the presence of periodontal pathogens, which are usually found in the oral cavity and saliva, in the atherosclerotic plaques of ApoE-deficient mice. In addition, in this review, the potential role of the APOE4 allele as an example of antagonistic pleiotropy during human evolution and its relation to oral health is discussed.

Transmission risk behaviour at enrolment in participants in the INSIGHT Strategic Timing of AntiRetroviral Treatment (START) trial

OBJECTIVES

A proportion of HIV-positive people have condomless sex. Antiretroviral treatment (ART) reduces infectiousness, but a substantial proportion of HIV-diagnosed people are not yet on ART. We describe baseline self-reported risk behaviours in ART-naïve Strategic Timing of AntiRetroviral Treatment (START) trial participants.

METHODS

All START participants completed a risk behaviour questionnaire. Data were collected on sociodemographics, lifestyle factors, health and wellbeing status and clinical status. Recent sexual behaviour and HIV transmission beliefs in the context of ART were also assessed. The primary interest was in condomless sex with serodifferent partners (CLS-D) in the past two months.

RESULTS

A total of 4601 of 4685 HIV-positive participants (98%) completed the questionnaire [2559 men who have sex with men (MSM), 803 heterosexual men and 1239 women]. Region of recruitment was Europe/Israel, 33%; South America/Mexico, 25%; Africa, 22%; other, 21%. Median age was 36 years [interquartile range (IQR) 29, 44 years]. Forty-five per cent reported white ethnicity and 31% black ethnicity. Two per cent had HIV viral load < 50 HIV-1 RNA copies/mL. Seventeen per cent (767 of 4601) reported CLS-D; 20% of MSM compared with 10% of heterosexual men and 14% of women. MSM were also more likely to report multiple CLS-D partners. Possible risk limitation measures (reported by more than half of those who had CLS-D) were seropositioning (receptive anal CLS-D only) or withdrawal (insertive anal CLS-D always without ejaculation). CLS-D was more commonly reported by participants from South America/Mexico and North America compared with Europe; among heterosexual men and women CLS-D was also more commonly reported among participants from Africa compared with Europe. Knowledge of ART impact on transmission risk was low.

CONCLUSIONS

A substantial minority recruited to the START study reported CLS-D at baseline. CLS-D reporting was higher in MSM than heterosexuals and varied significantly according to region of recruitment. A substantial proportion of MSM reporting CLS-D appear to take transmission risk limitation measures.

Evaluation of Subcutaneous Proleukin (interleukin-2) in a Randomized International Trial (ESPRIT): geographical and gender differences in the baseline characteristics of participants

BACKGROUND

ESPRIT, is a phase III, open-label, randomized, international clinical trial evaluating the effects of subcutaneous recombinant interleukin-2 (rIL-2) plus antiretroviral therapy (ART) versus ART alone on HIV-disease progression and death in HIV-1-infected individuals with CD4+ T-cells > or =300 cells/microL.

OBJECTIVES

To describe the baseline characteristics of participants randomized to ESPRIT overall and by geographic location.

METHOD

Baseline characteristics of randomized participants were summarized by region.

RESULTS

4,150 patients were enrolled in ESPRIT from 254 sites in 25 countries. 41%, 27%, 16%, 11%, and 5% were enrolled in Europe, North America, South America, Asia, and Australia, respectively. The median age was 40 years, 81% were men, and 76%, 11%, and 9% were Caucasian, Asian, and African American or African, respectively. 44% of women enrolled (n = 769) were enrolled in Thailand and Argentina. Overall, 55% and 38% of the cohort acquired HIV through male homosexual and heterosexual contact, respectively. 25% had a prior history of AIDS-defining illness; Pneumocystis jirovecii pneumonia, M. tuberculosis, and esophageal candida were most commonly reported. Median nadir and baseline CD4+ T-cell counts were 199 and 458 cells/muL, respectively. 6% and 13% were hepatitis B or C virus coinfected, respectively. Median duration of antiretroviral therapy (ART) was 4.2 years; the longest median duration was in Australia (5.2 years) and the shortest was in Asia (2.3 years). 17%, 13%, and 69% of participants began ART before 1995, between 1996 and 1997, and from 1998 onward, respectively. 86% used ART from two or more ART classes, with 49% using a protease inhibitor-based regimen and 46% using a nonnucleoside reverse transcriptase inhibitor-based regimen. 78% had plasma HIV RNA below detection (<500 cp/mL).

CONCLUSION

ESPRIT has enrolled a diverse population of HIV-infected individuals including large populations of women and patients of African-American/African and Asian ethnicity often underrepresented in HIV research. As a consequence, the results of the study may have wide global applicability.

[Chondromyxoid fibroma of the thoracic spine: a case report and review of the literature]

A case of chondromyxoid fibroma (CMF) arising from the 5th right costovertebral junction and spreading into spinal canal causing spinal cord compression is presented. A myelotomography revealed a complete block at T5 level. The patient underwent a decompressive laminectomy with removal of an epidural tumor. This specimen was sent for pathological examination and interpreted as a CMF. The patient had a neurological improvement, post operative MRI revealed a spinal cord free of compression, and we decided on the follow up of the case. Two years later there was recurrence of the tumor. A posterolateral access by costotransversectomy was made and the lesion was resected. The patient had a neurological improvement which persists on the follow up (two years, at present). Clinical, radiologic and histologic findings, surgical management and recurrence are discussed. The pertinent literature is reviewed.

Relative sizes of cortical visual areas in marmosets: functional and phylogenetic implications

Visual areas V1, V2 and MT (V5) were identified through myeloarchitectonic criteria and their sizes estimated in a flattened map of caudal cerebral cortex in the marmoset Callithrix penicillata. The ratio MT/V1 in this species is similar to values reported for other species of primates, but the ratio V2/V1 in Callithrix penicillata is smaller than that in macaques and larger than that in Aotus. The possible implications of these results are discussed.

Nonfunctioning paraganglioma of the posterior mediastinum. Case report

A case of nonfunctioning paraganglioma of the posterior mediastinum in a 20-year-old white man is presented. The diagnosis of aorticosympathetic paraganglioma (Glenner-Grimley classification) was established by histologic examination after surgical removal of the tumor.

A previously undescribed condition: tricho-odonto-onycho-dermal syndrome. A review of the tricho-odonto-onychial subgroup of ectodermal dysplasias

An apparently hitherto undescribed ectodermal dysplasia/malformation syndrome is presented. The patient, the last son in an outbred sibship of four males, presents scalp hypotrichosis, aplasia cutis congenita of the scalp, dental abnormalities, onychodyplasia, dry skin with hypochromic and atrophic (poikiloderma-like) spots with vicarious (marginal) hyperchromia, unusual facies, asymmetrical skull, absent right nipple, irregular areolae, palmar keratosis, dermatoglyphic alterations, syndactyly, clinodactyly, phalangeal aplasias and hypoplasias, right leukoma, abnormal EEG, and other findings. The aetiology is unknown. A review of seventeen ectodermal dysplasias is presented for different diagnosis.

A syndrome of hypohidrotic ectodermal dysplasia with normal teeth, peculiar facies, pigmentary disturbances, psychomotor and growth retardation, bilateral nuclear cataract, and other signs

This paper describes a 7-year-old girl with trichodysplasia, normal teeth, onychogryposis, hypohidrosis, psychomotor and growth retardation, dry and warm skin with follicular hyperkeratosis, pigmentary disturbances (hyper- and hypochromic spots), bilateral nuclear cataract, dermatoglyphic anomalies, and other signs. This condition is considered a new form of ectodermal dysplasia.