Emerald ash borer (
Agrilus planipennis
; EAB) has devastated populations of ash (
Fraxinus
spp.) trees in dozens of U.S. states and Canada over the past few decades. The continued survival of ...scattered ash trees known as “lingering ash” in heavily infested natural stands, however, offers evidence of genetic resistance or tolerance to EAB. These surviving or “lingering” ash individuals may form the basis for reforestation programs in EAB-impacted areas, and clonal mass-propagation of these genotypes can help accelerate these efforts. Between 2013 and 2018, we initiated embryogenic cultures by culturing immature zygotic embryos from open-pollinated (OP) seeds collected from several surviving white ash and green ash trees in Michigan and Pennsylvania. In addition, in 2018, we initiated cultures from crosses made between lingering green ash parents from the USDA Forest Service ash breeding program in Ohio. Somatic embryos were produced by growing cultures in liquid suspension, followed by fractionation and plating on semisolid medium to produce developmentally synchronous populations of somatic embryos. Somatic embryo germination and conversion were enhanced by a combination of pre-germination cold treatment and inclusion of activated charcoal and gibberellic acid in the germination medium. Ash somatic seedlings derived from OP explants grew rapidly following transfer to potting mix and somatic seedlings representing nine ash clones were acclimatized, grown in the greenhouse and planted in a preliminary field test, along with EAB-resistant Manchurian ash (
F. mandshurica
) and EAB-susceptible control seedlings. Somatic seedlings have now been produced from cultures that originated from seeds derived from the progeny of lingering green ash parents and an ex vitro germination protocol has shown some promise for accelerating early somatic seedling growth. Results of this research could provide the basis for scaled-up production of EAB-resistant ash varieties for seed orchard production for forest restoration and cultivar development for urban tree restoration.
The identification of tumor-initiating cells (TICs) has traditionally relied on surface markers including CD133, CD44, CD117, and the aldehyde dehydrogenase (ALDH) enzyme, which have diverse ...expression across samples. A more reliable indication of TICs may include the expression of embryonic transcription factors that support long-term self-renewal, multipotency, and quiescence. We hypothesize that SOX2, OCT4, and NANOG will be enriched in ovarian TICs and may indicate TICs with high relapse potential. We evaluated a panel of eight ovarian cancer cell lines grown in standard 2-D culture or in spheroid-enriching 3-D culture, and correlated expression with growth characteristics, TIC marker expression, and chemotherapy resistance. RNA-sequencing showed that cell cycle regulation pathways involving SOX2 were elevated in 3-D conditions. HGSOC lines had longer doubling-times, greater chemoresistance, and significantly increased expression of SOX2, OCT4, and NANOG in 3-D conditions. CD117+ or ALDH+/CD133+ cells had increased SOX2, OCT4, and NANOG expression. Limiting dilution in in vivo experiments implicated SOX2, but not OCT4 or NANOG, with early tumor-initiation. An analysis of patient data suggested a stronger role for SOX2, relative to OCT4 or NANOG, for tumor relapse potential. Overall, our findings suggest that SOX2 may be a more consistent indicator of ovarian TICs that contribute to tumor repopulation following chemotherapy. Future studies evaluating SOX2 in TIC biology will increase our understanding of the mechanisms that drive ovarian cancer relapse.
Modern society has rapidly grown highly digitized. Many elements of the human experience, like communications, events, interests, and likenesses, were and continue to be quantified into large amounts ...of data and diffused online. To power new algorithmic technologies, human capital is increasingly scraped and utilized by corporate interests for profit, transforming these pieces of our identity into products. The quantification, commodification, and surveillance of our data diminishes human experience and threatens our fundamental sense of identity. Reclaiming human dignity involves advocating for effective new regulations and privacy norms. We can recover agency over our own data and as a result, rebuild our digital culture into one that respects human identity and autonomy.
Emotion modulation is achieved through various strategies. We further validated a measure of emotion regulation (ER), the Negative Emotion Regulation Inventory (NERI), designed by Zimmermann and ...Iwanski (2014) to assess emotions and ER strategies in situations intended to induce sadness, fear, or anger. U.S. children 9–14 years old (n = 105) completed an adapted version of the NERI and measures of anxiety symptoms and attachment security. We replicated Zimmermann and Iwanski’s (2014) finding that ER strategies (adaptive regulation, social support seeking, dysfunctional rumination, expressive suppression) varied by emotion situation. We extended their study by showing that specific ER strategies were related to both anxiety symptoms and secure parent-child attachment. This cross-cultural replication and extension study provided some evidence for the reliability and validity of the adapted NERI in U.S. preadolescents.
Disease recurrence in high-grade serous ovarian cancer may be due to cancer stem-like cells (CSC) that are resistant to chemotherapy and capable of reestablishing heterogeneous tumors. The ...alternative NF-κB signaling pathway is implicated in this process; however, the mechanism is unknown. Here we show that TNF-like weak inducer of apoptosis (TWEAK) and its receptor, Fn14, are strong inducers of alternative NF-κB signaling and are enriched in ovarian tumors following chemotherapy treatment. We further show that TWEAK enhances spheroid formation ability, asymmetric division capacity, and expression of SOX2 and epithelial-to-mesenchymal transition genes VIM and ZEB1 in ovarian cancer cells, phenotypes that are enhanced when TWEAK is combined with carboplatin. Moreover, TWEAK in combination with chemotherapy induces expression of the CSC marker CD117 in CD117- cells. Blocking the TWEAK-Fn14-RelB signaling cascade with a small-molecule inhibitor of Fn14 prolongs survival following carboplatin chemotherapy in a mouse model of ovarian cancer. These data provide new insights into ovarian cancer CSC biology and highlight a signaling axis that should be explored for therapeutic development.
This study identifies a unique mechanism for the induction of ovarian cancer stem cells that may serve as a novel therapeutic target for preventing relapse.
Abstract
Ovarian cancer is the most lethal gynecological malignancy in the United States, with a known predilection for metastasizing to the omentum, a sheet of fatty peritoneal tissue that encloses ...the abdomen. This finding coincides with some evidence that ovarian cancer is more aggressive in the obese setting with worse overall survival. While it has been shown that ovarian cancer cells invade towards adipocytes in vitro, the mechanism by which they support formation of secondary tumors is not well understood. We hypothesize that soluble factors enriched in the obese setting are activating signaling pathways in tumor cells to drive migration and proliferation. To evaluate this hypothesis we co-cultured primary human omental adipocytes derived from obese female donors with ovarian cancer cell lines and profiled secretory factors (cytokines and adipokines) responsible for increasing tumor initiation in vivo and clonogenicity, proliferation, and drug resistance in vitro. Secretion of cytokines IL-6, IL-8, and CCL2 by adipocytes is enhanced when co-cultured with ovarian cancer cells. A subcutaneous tumor model showed that low dilutions of ovarian cancer cells require adipocytes for engraftment and tumor formation. A transplantation assay showed that ovarian cancer cells require the presence of adipocytes for sustained tumor-initiation capacity. Studies are underway to investigate adipocyte-secreted factors in this process. Our findings highlight the role of adipocytes in the ovarian tumor microenvironment and uncover signaling factors that may enhance ovarian cancer progression. Understanding these processes will enable the design of more effective therapies for treating ovarian cancer.
Citation Format: Jennifer Waters, Mikella Robinson, Samuel F. Gilbert, Logan J. Alexander, Carrie D. House. Role of secretory factors from obese-derived omentum in supporting ovarian cancer progression 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 6116.
Experiences of positive affect (PA) are common when interacting with animals and may help to build resilience. This study explored how children’s relationships with pet dogs, parents, and friends are ...related to their experiences of PA with their pet dog. In addition, we examined whether greater PA with pet dogs was related to children’s thriving. The sample (n = 115, 57 girls, 58 boys) included children 9–14 years of age who reported the quality of relationships with their pet dog (Positive Relationship Qualities, Friction, Pets as Substitutes), attachment security to parents, and positive and negative friendship quality. PA was assessed with child self-report before and after interacting with their dog, observed child and dog PA during the interaction, and reports of daily PA when interacting with the dog from a 7-day daily log. Children completed questionnaires to assess attachment security relationship with parents and friendship relationship quality. Children’s relationships with parents and friends were related to PA in the interaction session, whereas relationships with pet dogs, parents, and friends were all related to the daily experiences of PA. Children’s experiences of PA in daily interactions with pet dogs, parent-child attachment, and positive friendship quality were all related to children’s thriving. The findings suggest that experiences of PA may be one mechanism that accounts for the effects of animals on children’s development.
Alaska is a unique US state because of its large size, geographically disparate population density, and physical distance from the contiguous United States. Here, we describe a pattern of SARS-CoV-2 ...variant emergence across Alaska reflective of these differences. Using genomic data, we found that in Alaska, the Omicron sublineage BA.2.3 overtook BA.1.1 by the week of 27 February 2022, reaching 48.5% of sequenced cases. On the contrary, in the contiguous United States, BA.1.1 dominated cases for longer, eventually being displaced by BA.2 sublineages other than BA.2.3. BA.2.3 only reached a prevalence of 10.9% in the contiguous United States. Using phylogenetics, we found evidence of potential origins of the two major clades of BA.2.3 in Alaska and with logistic regression estimated how it emerged and spread throughout the state. The combined evidence is suggestive of founder events in Alaska and is reflective of how Alaska's unique dynamics influence the emergence of SARS-CoV-2 variants.
Abstract
Background: Ovarian cancer is the most lethal gynecologic malignancy mainly due to a high prevalence of chemotherapy-resistant recurrent disease. This mechanism is unknown but recent studies ...have pointed to a small population of chemoresistant cancer stem cells (CSC) as the driver of these recurrences. Traditional surface markers of cancer stem cells (CD44, ALDH, CD117, etc.) have shown mixed success in identifying this subpopulation, with different cell lines and patient samples exhibiting dissimilar profiles. These markers are often related to the cell of origin and are not necessarily specific to CSCs. As such, a reporter that responds to functional features of stem cells would be beneficial in identifying the CSC subpopulation regardless of cell line and patient sample. Here we demonstrate that using a reporter to detect SOX2 and OCT4 overexpression (called SORE6) can identify the CSC subpopulation within ovarian cancer cell lines.
Methods: The SORE6 reporter was stably transduced into OV90 and ACI23 ovarian cancer cell lines. The subpopulation of cells having high SOX2/OCT4 expression (SORE6+) were isolated using fluorescence assisted cell sorting (FACs) and evaluated for CSC characteristics relative to SORE6- cells. Gene expression, viability, spheroid formation capacity, and tumorigenicity was assessed for both SORE6+ and SORE6- cells. In vivo limiting dilution analyses were performed on athymic nude female mice using subcutaneous injection.
Results: Compared to the bulk population which has low levels of SOX2/OCT4 expression (SORE6-), SORE6+ cells showed a 1.5-fold increase in SOX2/OCT4/NANOG transcript levels in ACI23 cells and 2 to 15-fold increase in these transcript levels in the OV90 cells. SORE6+ cells showed enhanced chemoresistance when treated with conventional chemotherapies for ovarian cancer, carboplatin and paclitaxel, although this difference was more dramatic in the OV90 cells (four-fold) relative to ACI23 (two-fold). These findings indicate that SOX2/OCT4 expression could contribute to drug resistance and clinical recurrence. SORE6+ cells also showed an increased capacity to form spheroids in low-serum conditions and again this difference was more dramatic in the OV90 cells. In vivo limiting dilution studies are underway but appear to show significant differences in tumorigenicity at low dilutions of ≤5,000 cells/mouse.
Conclusion: The SORE6 reporter construct identifies CSC populations within ovarian cancer cell lines and may be a reliable tool for isolating CSCs that depend on SOX2 and OCT4 expression. Use of this reporter will enhance our understanding of mechanisms that support chemoresistance and enable the study of CSC dynamics within the tumor microenvironment, both of which have significant implications for ovarian cancer progression and treatment.
Citation Format: Samuel F. Gilbert, Mikella Robinson, Logan A. Alexander, Omar Lujano-Olazaba, Jacqueline M. Lara, Jennifer A. Waters, Omid Patrus, Alex Horkowitz, Carrie D. House. Identification and isolation of ovarian cancer stem cell populations using a novel functional reporter may provide new insights into ovarian cancer cell dynamics and drug resistance 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 4941.
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