RESUMO
Purpose: The global rise in cancer incidence has been accompanied by disproportionately high morbidity and mortality rates in low- and middle-income countries. Many patients who are offered potentially curative treatment for cervical cancer in low- and middle-income countries never return to start treatment for reasons that are poorly documented and little understood. We investigated the interplay of sociodemographic, financial, and geographic factors as barriers to care among such patients in Botswana and Zimbabwe. Methods and Materials: Patients seen in consultation between 2019 and 2021 who were >3 months late for an appointment to initiate definitive treatment were contacted via telephone and invited to complete a survey. Afterward, an intervention connected patients with resources and counseling to return for treatment. Follow-up data were collected 3 months later to ascertain the outcomes of the intervention. Fisher exact tests analyzed the relationship between the putative number and types of barriers and demographics. Results: We recruited 40 women who initially presented for oncology care but did not return for treatment at [Princess Marina Hospital] in Botswana (n = 20) and [Parirenyatwa General Hospital] in Zimbabwe (n = 20) to complete the survey. Overall, married women experienced more barriers than unmarried women (P < .001), and unemployed women were 10 times more likely to report a financial barrier than employed women (P = .02). In Zimbabwe, financial barriers and belief-associated barriers (eg, fear of treatment) were reported. In Botswana, many patients noted scheduling obstacles associated with administrative delays and COVID-19. At follow-up, 16 Botswana patients and 4 Zimbabwe patients had returned for treatment. Conclusions: Financial and belief barriers identified in Zimbabwe showcase the importance of targeting cost and health literacy to reduce apprehensions. In Botswana, administrative challenges could be addressed with patient navigation. Improving our understanding of the specific barriers to cancer care could enable us to help patients who might otherwise default.
RESUMO
Although cell density is known to affect numerous biological processes including gene expression and cell fate specification, mechanistic understanding of what factors link cell density to global gene regulation is lacking. Here, we reveal that the expression of thousands of genes in mouse embryonic stem cells (mESCs) is affected by cell seeding density and that low cell density enhances the efficiency of differentiation. Mechanistically, ß-catenin is localized primarily to adherens junctions during both self-renewal and differentiation at high density. However, when mESCs differentiate at low density, ß-catenin translocates to the nucleus and associates with Tcf7l1, inducing co-occupied lineage markers. Meanwhile, Esrrb sustains the expression of pluripotency-associated genes while repressing lineage markers at high density, and its association with DNA decreases at low density. Our results provide new insights into the previously neglected but pervasive phenomenon of density-dependent gene regulation.
RESUMO
Approximately, 30% of embryonic stem cells (ESCs) die after exiting self-renewal, but regulators of this process are not well known. Yap1 is a Hippo pathway transcriptional effector that plays numerous roles in development and cancer. However, its functions in ESC differentiation remain poorly characterized. We first reveal that ESCs lacking Yap1 experience massive cell death upon the exit from self-renewal. We subsequently show that Yap1 contextually protects differentiating, but not self-renewing, ESC from hyperactivation of the apoptotic cascade. Mechanistically, Yap1 strongly activates anti-apoptotic genes via cis-regulatory elements while mildly suppressing pro-apoptotic genes, which moderates the level of mitochondrial priming that occurs during differentiation. Individually modulating the expression of single apoptosis-related genes targeted by Yap1 is sufficient to augment or hinder survival during differentiation. Our demonstration of the context-dependent pro-survival functions of Yap1 during ESC differentiation contributes to our understanding of the balance between survival and death during cell fate changes.
