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To evaluate disease-free survival (DFS) as a surrogate endpoint for overall survival (OS) using aggregate-level data from resectable esophageal or gastroesophageal junction cancer (EC/GEJC) trials assessing therapies in (neo)adjuvant and perioperative settings.A systematic literature review was conducted to identify trials reporting OS and DFS, or compatible progression-free survival (PFS). Bivariate random-effects meta-analysis was used to estimate correlation between the treatment effects on DFS/PFS and OS, and weighted linear regression models assuming trial sample sizes as weights were used to estimate surrogacy equations. The primary analysis consisted of trials across all treatment settings, and secondary analysis consisted of trials only in the adjuvant setting. Leave-one-out cross-validation (LOOCV) was performed to measure the stability and predictive accuracy of the surrogacy equations while surrogate threshold effects (STE)-the minimum treatment effect on DFS/PFS that would translate into a positive OS benefit-were derived to measure their usefulness.The primary analysis included 26 trials. The estimated correlation coefficient between the hazard ratio (HR) of DFS/PFS (HROur meta-analysis suggests that HR

Systematic identification of signaling pathways required for the fitness of cancer cells will facilitate the development of new cancer therapies. We used gene essentiality measurements in 1,086 cancer cell lines to identify selective coessentiality modules and found that a ubiquitin ligase complex composed of UBA6, BIRC6, KCMF1, and UBR4 is required for the survival of a subset of epithelial tumors that exhibit a high degree of aneuploidy. Suppressing BIRC6 in cell lines that are dependent on this complex led to a substantial reduction in cell fitness in vitro and potent tumor regression in vivo. Mechanistically, BIRC6 suppression resulted in selective activation of the integrated stress response (ISR) by stabilization of the heme-regulated inhibitor, a direct ubiquitination target of the UBA6/BIRC6/KCMF1/UBR4 complex. These observations uncover a novel ubiquitination cascade that regulates ISR and highlight the potential of ISR activation as a new therapeutic strategy.Significance:We describe the identification of a heretofore unrecognized ubiquitin ligase complex that prevents the aberrant activation of the ISR in a subset of cancer cells. This provides a novel insight on the regulation of ISR and exposes a therapeutic opportunity to selectively eliminate these cancer cells.See related commentary Leli and Koumenis, p. 535.This article is highlighted in the In This Issue feature, p. 517

Supplementary Figure S1 shows the strategy and result of co-essentiality module identificationfrom the DepMap CRISPR screen dataset and further characterization of the BIRC6 module. Supplementary Figure S2 shows the viability effect of BIRC6 depletion in BIRC6-dependent and -nondependent cancer cells lines as well asin nontransformed cells. Supplementary Figure S3 shows in vitro confirmations of the inducible BIRC6 depletion (by RNAi and CRISPR) systems as well as the effect of BIRC6 depletion on metastasis in xenograft models. Supplementary Figure S4 shows detailed results for the allele competition assay to evaluate the role of the BIR and UBC domains of BIRC6 and further evidence for the physical assembly of BIRC6 ubiquitin ligase complex. Supplementary Figure S5 shows evidence for the selective activation of the p-eIF2alpha/ATF4 arm of UPR (or ISR) upon BIRC6 depletion. Supplementary Figure S6 shows evidence supporting the importance of HRI-mediated ISR activation as a mechanism underlying the loss of viability caused by BIRC6 complex suppression. Supplementary Figure S7 shows evidence for the direct regulation of HRI ubiquitination and degradation by the BIRC6 complex Supplementary Figure S8 shows elevated expression of HRI mRNA in the tumor samples compared to the normal samples in large-scale datasets (TCGA, TARGET and GTEx). Supplementary Figure S9 shows the inefficiency of the gene expression and copy number of the functionally related genes in predicting BIRC6 dependency. Supplementary Table S1 lists the top 50 co-essentiality modules identified in the analysis explained in Supplementary Figure S1A. Supplementary Table S2 lists the key DNA and RNA sequences used in this study.

We hypothesized that candidate dependencies for which there are small molecules that are either approved or in advanced development for a nononcology indication may represent potential therapeutic targets. To test this hypothesis, we performed genome-scale loss-of-function screens in hundreds of cancer cell lines. We found that knockout of EGLN1, which encodes prolyl hydroxylase domain-containing protein 2 (PHD2), reduced the proliferation of a subset of clear cell ovarian cancer cell lines in vitro. EGLN1-dependent cells exhibited sensitivity to the pan-EGLN inhibitor FG-4592. The response to FG-4592 was reversed by deletion of HIF1A, demonstrating that EGLN1 dependency was related to negative regulation of HIF1A. We also found that ovarian clear cell tumors susceptible to both genetic and pharmacologic inhibition of EGLN1 required intact HIF1A. Collectively, these observations identify EGLN1 as a cancer target with therapeutic potential.Significance:These findings reveal a differential dependency of clear cell ovarian cancers on EGLN1, thus identifying EGLN1 as a potential therapeutic target in clear cell ovarian cancer patients.

Supplementary Figure 1 identifies EGLN1 as a cancer dependency in RNAi and CRISPR datasets and contains all significant associations. Supplementary Figure 2 is a lineage analysis of EGLN1 dependency within RNAi dataset. Supplementary Figure 3 is an immunoblot showing EGLN1 knockout in EGLN1-insensitive cell line. Supplementary Figure 4 shows pan-EGLN inhibition affects proliferation and apoptosis. Supplementary Figure 5 shows specific EGLN1 inhibitor IOX2 and VHL inhibitor VH298 inhibit proliferation. Supplementary Figure 6 shows differentially expressed genes in EGLN1-KO cells. Supplementary Figure 7 shows increased apoptosis in vivo when inhibiting EGLN1 or VHL.

Supplementary Tables 1-6. Supplementary Table 1 contains a list of constructs used in this manuscript. Tab 2 with Supplementary table 2 is a list of all six-sigma genes we identified. Supplementary table 3 contains EGLN1 CRISPR Associations with mutations, gene expression, CRISPR dependencies and copy number. Supplementary table 4 contains EGLN1 RNAi Associations with mutations, gene expression, RNAi dependencies and copy number. Supplementary Table 5 contains all cell line information and annotations used for this manuscript. Supplementary Table 6 contains RNA sequence data from EGLN1 KO cells and EGLN1 WT cells.

The onset of the COVID-19 pandemic has intensified the need for online food delivery services (such as Deliveroo and Foodpanda), creating new job opportunities for South Asian youths. However, outbreaks of infected cases in districts populated by South Asians have spurred ‘racist’ remarks by customers, perhaps triggered by a flurry of negative mainstream news reports and social media outbursts targeted at South Asians. These behaviours reveal the added precariousness of ethnic minority employment. This paper examines the inter-sectional politics of race and class involved in platformed work, in the case of food delivery services. It discusses how the algorithmically controlled platformed economy may have an impact on racial minority workers. Employing the conceptual framing of ‘invisibility’, and notions around ‘platformed/ gig labour’, it argues that neo-liberalised infrastructural capitalism aggravates algorithmic surveillance of racial minority workers. It suggests the possible resilience of racial minority workers in the globally popular business model.

Targeting of mutated oncogenes has led to the identification of new targeted therapies. However, druggable oncogenes do not occur in most cancers. Systematic identification of signaling pathways required for the fitness of cancer cells will facilitate the development of new cancer therapies. We used gene essentiality measurements in 793 cancer cell lines to identify selective co-essentiality modules and found that a ubiquitination ligase complex composed of UBA6, BIRC6, KCMF1 and UBR4, which encode an E1, E2 and two heterodimeric E3 subunits, respectively, is required for the survival of a subset of epithelial tumors, particularly subtypes of breast cancer. Suppressing BIRC6 in cell lines that are dependent on this complex led to a substantial reduction in cell fitness in vitro and potent tumor regression in vivo. Mechanistically, BIRC6 suppression resulted in selective activation of the integrated stress response (ISR) by stabilization and upregulation of the heme-regulated inhibitor (HRI), a direct ubiquitination target of the UBA6/BIRC6/KCMF1/UBR4 complex. These observations uncover a novel ubiquitination cascade that regulates ISR and highlight the potential of ISR activation as a new therapeutic strategy. Citation Format: Lisa D Cervia, Tsukasa Shibue, Benjamin Gaeta, Ashir A Borah, Lisa Leung, Naomi Li, Nancy Dumont, Alfredo Gonzalez, Nolan Bick, Mariya Kazachkova, Joshua M Dempster, John M Krill-Burger, Federica Piccioni, Namrata D Udeshi, Meagan E Olive, Steven A Carr, David E Root, James M McFarland, Francisca Vazquez, William C Hahn. A ubiquitination cascade regulating the integrated stress response and survival in carcinomas [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-09-01.

Systematic identification of signaling pathways required for the fitness of cancer cells will facilitate the development of new cancer therapies. We used gene essentiality measurements in 1,086 cancer cell lines to identify selective coessentiality modules and found that a ubiquitin ligase complex composed of UBA6, BIRC6, KCMF1, and UBR4 is required for the survival of a subset of epithelial tumors that exhibit a high degree of aneuploidy. Suppressing BIRC6 in cell lines that are dependent on this complex led to a substantial reduction in cell fitness in vitro and potent tumor regression in vivo. Mechanistically, BIRC6 suppression resulted in selective activation of the integrated stress response (ISR) by stabilization of the heme-regulated inhibitor, a direct ubiquitination target of the UBA6/BIRC6/KCMF1/UBR4 complex. These observations uncover a novel ubiquitination cascade that regulates ISR and highlight the potential of ISR activation as a new therapeutic strategy.Significance:We describe the identification of a heretofore unrecognized ubiquitin ligase complex that prevents the aberrant activation of the ISR in a subset of cancer cells. This provides a novel insight on the regulation of ISR and exposes a therapeutic opportunity to selectively eliminate these cancer cells.See related commentary Leli and Koumenis, p. 535.This article is highlighted in the In This Issue feature, p. 517

321 Background: OS is the gold standard efficacy measure in oncology; however, its need for prolonged follow-up motivates the establishment of SEs for earlier assessments of emerging treatments. We assessed DFS as a candidate SE for OS in early-stage EC/GEJC using data from Medicare beneficiaries with cancer in the SEER registry. Methods: Patients aged > 65 years in the US with resective surgery after a primary diagnosis of stage 2 or 3 EC/GEJC between 2009-2017 were analyzed (N=925; median follow-up 26.2 months). Surrogacy was assessed via both individual-level association of DFS to OS, and via the association between the treatment effects on DFS and OS. Strength of individual-level association was measured via Spearman’s rank correlation (ρ) non-parametrically and Kendall’s τ using copula functions. The strength of correlation between the treatment effects on DFS and OS—measured by the coefficient of determination (R2) and the surrogate threshold effect (STE), which is the minimum DFS benefit that would translate into statistically significant OS benefit—was derived from a regression model predicting OS hazard ratio (HR) from DFS HR. Patients were classified in clusters based on treatments they received and baseline characteristics (age, sex, index year, staging, and race/ethnicity). Propensity score matching addressed imbalances in baseline characteristics between the treatment and control groups in the constructed clusters. Predictive accuracy of the surrogacy equation was assessed internally via leave-one-out cross-validation and externally via predictions made for 26 RCTs of early-stage EC/GEJC. Results: Patients were mostly male (84%), non-Hispanic white (89.3%), with median age of 71.8 years and almost evenly distributed between cancer stages 2 (50.4%) and 3 (49.6%). Among patients receiving adjuvant (23.6%) or neoadjuvant (82.8%) treatment, most (81.7% of adjuvant and 92.0% of neoadjuvant therapies) received multi-agent chemotherapy. Spearman’s ρ was estimated to be 0.76 (95% CI: 0.70, 0.89) whereas estimates for Kendall’s τ ranged between 0.62 and 0.79. Estimated R2 for the correlation between treatment effects was 0.92 (95% CI: 0.56, 1.00) and estimated from the surrogacy equation log(HROS) = 0.02 + 1.09 × log(HRDFS) with a corresponding STE of 0.86. The 95% prediction intervals generated from this equation contained the raw OS HRs for 91% of the clusters in the internal validation, and 89% of the RCTs in the external validation. Conclusions: Correlations between DFS and OS, and between the treatment effects on these endpoints, were both moderate. The highly accurate surrogacy equation between the treatment effects can enable earlier assessments of OS benefit from the DFS benefit for early-stage EC/GEJC treatments in the real-world setting.

Introduction High-quality epidemiological evidence on the relationship between the occupational environment and ovarian cancer risk is limited. Most studies had very few cases, did not adjust for important confounders, and lacked information on specific workplace exposures. Objectives To investigate the relationship between occupation, specific workplace exposures, and ovarian cancer risk. Methods In a population-based case-control study conducted in Montreal, Canada (2011–2016), lifetime occupational histories were collected for 492 cases and 897 controls. For each job held by a participant, occupational and industrial classification codes were coded by an industrial hygienist. To identify specific workplace exposures, job codes were linked to the Canadian job-exposure matrix. Twenty-three agents with relatively high prevalence were selected. Occupations were examined by comparing participants ever employed in a given occupation for at least ten years vs. never employed in that occupation. For specific exposures, ever exposure, exposure duration, and cumulative exposure to selected agents were analyzed. Odds ratios (OR) and 95% confidence intervals (CI) for associations with ovarian cancer risk were estimated using logistic regression. Results Elevated ORs were observed for accountants (OR=2.03, 95% CI: 1.09–3.76); hairdressers, barbers, and beauticians (OR=3.22, 95% CI: 1.25–8.28); sewers and embroiderers (OR=1.89, 95% CI: 0.78–4.59); saleswomen, shop assistants, and demonstrators (OR=1.42, 95% CI: 0.70–2.89); and occupations in retail trade (OR=1.59, 95% CI: 1.05–2.39). For specific exposures, increased risks were suggested for cosmetic talc, ammonia, hydrogen peroxide, hair dust, propellant gases, fluorocarbons, ethanol, cellulose, and polyester fibres. Hairdressers, barbers, and beauticians were the most frequent occupation exposed to six out of nine specific workplace exposures among participants. Conclusion Study results suggest that certain occupations may be associated with increased ovarian cancer risks, but it is difficult to determine specific exposures that may contribute to the increased risks. Future larger studies with expert assessments of specific occupational exposures may better characterize co-exposures.

Introduction: Prior to ablation, predicting the site of origin (SOO) of outflow tract ventricular arrhythmia (OTVA), can inform patient consent and facilitate appropriate procedural planning. We set out to determine if OTVA variability can accurately predict SOO. Methods: Consecutive patients with a clear SOO identified at OTVA ablation had their prior 24-hour ambulatory ECGs retrospectively analysed (derivation cohort). Percentage ventricular ectopic (VE) burden, hourly VE values, episodes of trigeminy/bigeminy, and the variability in these parameters were evaluated for their ability to distinguish right from left sided SOO. Effective parameters were then prospectively tested on a validation cohort of consecutive patients undergoing their first OTVA ablation. Results: High VE variability (coefficient of variation ≥ 0.7) and the presence of any hour with < 50 VE, were found to accurately predict RVOT SOO in a derivation cohort of 40 patients. In a validation cohort of 29 patients, the correct SOO was prospectively identified in 23/29 patients (79.3%) using CoV, and 26/29 patients (89.7%) using VE < 50. Including current ECG algorithms, VE < 50 had the highest Youden Index (78), the highest positive predictive value (95.0%) and the highest negative predictive value (77.8%). Conclusion: VE variability and the presence of a single hour where VE < 50 can be used to accurately predict SOO in patients with OTVA. Accuracy of these parameters compares favourably to existing ECG algorithms.

We hypothesized that candidate dependencies for which there are small molecules that are either approved or in advanced development for a nononcology indication may represent potential therapeutic targets. To test this hypothesis, we performed genome-scale loss-of-function screens in hundreds of cancer cell lines. We found that knockout of EGLN1, which encodes prolyl hydroxylase domain-containing protein 2 (PHD2), reduced the proliferation of a subset of clear cell ovarian cancer cell lines in vitro. EGLN1-dependent cells exhibited sensitivity to the pan-EGLN inhibitor FG-4592. The response to FG-4592 was reversed by deletion of HIF1A, demonstrating that EGLN1 dependency was related to negative regulation of HIF1A. We also found that ovarian clear cell tumors susceptible to both genetic and pharmacologic inhibition of EGLN1 required intact HIF1A. Collectively, these observations identify EGLN1 as a cancer target with therapeutic potential. Significance: These findings reveal a differential dependency of clear cell ovarian cancers on EGLN1, thus identifying EGLN1 as a potential therapeutic target in clear cell ovarian cancer patients.

Background: Shift work causing circadian disruption is classified as a “probable carcinogen” and may contribute to the pathogenesis of hormone-sensitive cancers. This study investigated shift work exposure in relation to epithelial ovarian cancer (EOC) risk. Methods: In a population-based case–control study with 496 EOC cases and 906 controls, lifetime occupational histories were collected and used to calculate cumulative years of shift work exposure, average number of night shifts per month, and average number of consecutive night shifts per month. ORs and 95% confidence intervals (CI) for associations with EOC risk were estimated using logistic regression. Associations were also examined according to chronotype and menopausal status. Results: More than half of the cases (53.4%) and controls (51.7%) worked evening and/or night shifts. There was no clear pattern of increasing EOC risk with increasing years of shift work; the adjusted OR of EOC comparing the highest shift work category versus never working shift work was 1.20 (95% CI, 0.89–1.63). This association was more pronounced among those self-identified as having a “morning” chronotype (OR, 1.64; 95% CI, 1.01–2.65). Associations did not greatly differ by menopausal status. Conclusions: These results do not strongly demonstrate a relationship between shift work and EOC risk. Impact: This study collected detailed shift work information and examined shift work patterns according to shift times and schedules. The findings highlight that chronotype should be considered in studies of shift work as an exposure.

Synthetic lethality-an interaction between two genetic events through which the co-occurrence of these two genetic events leads to cell death, but each event alone does not-can be exploited for cancer therapeutics1. DNA repair processes represent attractive synthetic lethal targets, because many cancers exhibit an impairment of a DNA repair pathway, which can lead to dependence on specific repair proteins2. The success of poly(ADP-ribose) polymerase 1 (PARP-1) inhibitors in cancers with deficiencies in homologous recombination highlights the potential of this approach3. Hypothesizing that other DNA repair defects would give rise to synthetic lethal relationships, we queried dependencies in cancers with microsatellite instability (MSI), which results from deficient DNA mismatch repair. Here we analysed data from large-scale silencing screens using CRISPR-Cas9-mediated knockout and RNA interference, and found that the RecQ DNA helicase WRN was selectively essential in MSI models in vitro and in vivo, yet dispensable in models of cancers that are microsatellite stable. Depletion of WRN induced double-stranded DNA breaks and promoted apoptosis and cell cycle arrest selectively in MSI models. MSI cancer models required the helicase activity of WRN, but not its exonuclease activity. These findings show that WRN is a synthetic lethal vulnerability and promising drug target for MSI cancers.

Targeting of mutated oncogenes has led to the identification of new targeted therapies. However, druggable oncogenes do not occur in most cancers. Systematic identification of signaling pathways required for the fitness of cancer cells will facilitate the development of new cancer therapies. We used gene essentiality measurements in 793 cancer cell lines to identify selective co-essentiality modules and found that a ubiquitination ligase complex composed of UBA6, BIRC6, KCMF1 and UBR4, which encode an E1, E2 and two heterodimeric E3 subunits, respectively, is required for the survival of a subset of epithelial tumors. Suppressing BIRC6 in cell lines that are dependent on this complex led to a substantial reduction in cell fitness in vitro and potent tumor regression in vivo. Mechanistically, BIRC6 suppression resulted in selective activation of the integrated stress response (ISR) by stabilization and upregulation of the heme-regulated inhibitor (HRI), a direct ubiquitination target of the UBA6/BIRC6/KCMF1/UBR4 complex. These observations uncover a novel ubiquitination cascade that regulates ISR and highlight the potential of ISR activation as a new therapeutic strategy. Citation Format: Lisa D. Cervia, Tsukasa Shibue, Benjamin Gaeta, Ashir A. Borah, Lisa Leung, Naomi Li, Nancy Dumont, Alfredo Gonzalez, Nolan Bick, Mariya Kazachkova, Joshua M. Dempster, John M. Krill-Burger, Federica Piccioni, Namrata D. Udeshi, Meagan E. Olive, Steven A. Carr, David E. Root, James M. McFarland, Francisca Vazquez, William C. Hahn. A ubiquitination cascade regulating the integrated stress response and survival in carcinomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 73.

Aims: To investigate the utility of adenosine administration to test the durability of cavotricuspid isthmus (CTI) block after radiofrequency (RF) catheter ablation for typical atrial flutter. Methods: Adenosine 10mg was administered by bolus injection through a femoral sheath at 5 minutes after apparent completion of CTI ablation in consecutive patients, and its effect on CTI conduction was recorded. Conduction in both directions across the CTI was tested repeatedly until 20 minutes after the last energy delivery. Results: Among 132 patients treated with a Blazer 10mm (n=126) or 8mm (n=6) ablation catheter, bidirectional block of the CTI was achieved in all cases. Adenosine administration was followed by a transient recurrence of conduction in 3 cases (2.3%); in all of these, a persistent recurrence of CTI conduction was observed within the waiting period. Persistent recurrence of CTI conduction occurred within the waiting period in 3 patients (2.3%) whose adenosine test had been negative. In all cases, further RF delivery achieved CTI block that persisted to the end of a 20-minute waiting period. During 38 months of follow-up, 131 patients (99.2%) remained free of clinical recurrence of typical flutter. Conclusion: Administration of adenosine 10mg at 5 minutes after RF delivery reveals latent conduction in the CTI in some but not all cases that are revealed by a 20-minute wait. At this dosage and at this time-point, adenosine testing is not an adequate substitute for a waiting period.

Background Esophageal thermal injury can occur after radiofrequency (RF) ablation in the left atrium to treat atrial fibrillation. Existing methods to prevent esophageal injury have various limitations in deployment and uncertainty in efficacy. A new esophageal heat transfer device currently available for whole-body cooling or warming may offer an additional option to prevent esophageal injury. We sought to develop a mathematical model of this process to guide further studies and clinical investigations and compare results to real-world clinical data. Results The model predicts that the esophageal cooling device, even with body-temperature water flow (37 °C) provides a reduction in esophageal thermal injury compared to the case of the non-protected esophagus, with a non-linear direct relationship between lesion depth and the cooling water temperature. Ablation power and cooling water temperature have a significant influence on the peak temperature and the esophageal lesion depth, but even at high RF power up to 50 W, over durations up to 20 s, the cooling device can reduce thermal impact on the esophagus. The model concurs with recent clinical data showing an 83% reduction in transmural thermal injury when using typical operating parameters. Conclusions An esophageal cooling device appears effective for esophageal protection during atrial fibrillation, with model output supporting clinical data. Analysis of the impact of ablation power and heart wall dimensions suggests that cooling water temperature can be adjusted for specific ablation parameters to assure the desired myocardial tissue ablation while keeping the esophagus protected.

We investigated effects of apterous mutation ap(56f) on circadian locomotor activity, eclosion rhythms, and transcript levels of period and timeless in Drosophila. We investigated circadian locomotor activity and eclosion rhythms in ap(56f)and wild-type flies, their F1 and F2 offspring, and wingless vestigial mutants and show that ap(56f) disrupts circadian locomotor rhythms in a genetically recessive manner, that is not caused by the absence of wings. The ap(blt) strain also showed impaired circadian activity rhythms, providing independent evidence for a significant role of apterous in circadian locomotor rhythm expression. The ap(56f) mutation did not disrupt a circadian eclosion rhythm or rhythmic expression of the period and timeless clock genes, indicating that apterous is not essential for circadian clock function, but is necessary for coupling locomotor activity to a circadian clock. Timeless transcription was reduced in ap(56f) flies in 12:12 LD, suggesting that apterous may modulate core clock gene expression.

Systematic identification of signaling pathways required for the viability of cancer cells will facilitate the development of novel cancer therapies. We used gene essentiality measurements in 726 cancer cell lines to identify selective co-essentiality modules and found a functional ubiquitination cascade containing UBA6, BIRC6, KCMF1 and UBR4, which encode an E1, E2, and two heterodimeric E3 subunits, respectively, as a vulnerability in a subset of epithelial tumors. Suppressing BIRC6 in cancer cell lines that are dependent on this ubiquitination cascade led to a strong reduction in cell fitness in vitro, and to potent tumor regression and metastasis suppression in vivo. Mechanistically, BIRC6 suppression resulted in selective and robust activation of the integrated stress response (ISR) signaling via upregulation of the heme-regulated inhibitor (HRI). Using proteomic profiling, we found that HRI itself is a key degradation target of the UBA6/BIRC6/KCMF1/UBR4 cascade. These observations demonstrate a protein ubiquitination cascade regulating ISR and highlight the potential of this cascade as a novel therapeutic target for a subset of epithelial cancers. Citation Format: Lisa D. Cervia, Tsukasa Shibue, Benjamin Gaeta, Ashir Borah, Lisa Leung, Naomi Li, Nancy Dumont, Alfredo Gonzalez, Nolan Bick, Mariya Kazachkova, Joshua Dempster, John M. Krill-Burger, Namrata Udeshi, Meagan Olive, Steven A. Carr, David E. Root, Federica Piccioni, James M. McFarland, Francisca Vazquez, William C. Hahn. A ubiquitination cascade regulates the integrated stress response and epithelial cancer survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1950.

We thank Drs. Morfeld and Erren for conveying their agreement of our consideration of chronoytpe as a potential effect modifier, and not as a potential confounder, in the relationship between shift work and ovarian cancer ([1][1]). Their proposition to consider chronodisruption as a single time

Summary paragraph Synthetic lethality, an interaction whereby the co-occurrence of two or more genetic events lead to cell death but one event alone does not, can be exploited to develop novel cancer therapeutics1. DNA repair processes represent attractive synthetic lethal targets since many cancers exhibit an impaired DNA repair pathway, which can lead these cells to become dependent on specific repair proteins2. The success of poly (ADP-ribose) polymerase 1 (PARP-1) inhibitors in homologous recombination-deficient cancers highlights the potential of this approach in clinical oncology3,4. Hypothesizing that other DNA repair defects would give rise to alternative synthetic lethal relationships, we asked if there are specific dependencies in cancers with microsatellite instability (MSI), which results from impaired DNA mismatch repair (MMR). Here we analyzed data from large-scale CRISPR/Cas9 knockout and RNA interference (RNAi) silencing screens and found that the RecQ DNA helicase WRN was selectively essential in MSI cell lines, yet dispensable in microsatellite stable (MSS) cell lines. WRN depletion induced double-strand DNA breaks and promoted apoptosis and cell cycle arrest selectively in MSI models. MSI cancer models specifically required the helicase activity, but not the exonuclease activity of WRN. These findings expose WRN as a synthetic lethal vulnerability and promising drug target in MSI cancers.

Previously, we have used an integrated approach to use genome-scale screening in RNAi and CRISPR-Cas9 to identify several putative cancer dependencies. From these putative dependencies, we discovered EGLN1 was a significant and selective dependency in ovarian cancer and EGLN1 dependency was further enriched in clear-cell ovarian cancers. Genetic knockout and small-molecule inhibition of EGLN1 reduced cell proliferation and increased apoptosis in vitro and in vivo. We found the function of EGLN1 as a cancer dependency is through its canonical role as a negative HIF1A regulator and knockout of HIF1A, but not HIF2A, rescues genetic knockout and small-molecule inhibition of EGLN1. Genetic and small-molecule suppression of VHL, downstream of EGLN1 in the degradation of HIF1A, similarly reduces proliferation and increases apoptosis, and is rescued by HIF1A knockout. Further, we found that forced expression of a mutated HIF1A that blocks EGLN1-dependent hydroxylation reduces proliferation and promotes apoptosis. Using RNA-sequencing, we identified several putative downstream targets of HIF1A and confirmed that HIF1A directly binds and drives transcription of negative MYC regulator MXI1. Further, we found that knockout of MXI1 reduced the effects of EGLN1-mediated suppression, indicating HIF1A-driven MYC suppression as one mechanism underlying EGLN1 dependency. Further understanding of HIF1A-mediated suppression of ovarian cancer progression will be critical to potential small-molecule therapy. Citation Format: Colles Price, Stanley Gill, Zandra V. Ho, Shawn M. Davidson, Erin Merkel, James M. McFarland, Lisa Leung, Andrew Tang, Maria Kost-Alimova, Aviad Tsherniak, Oliver Jonas, Francisca Vazquez, William C. Hahn. Understanding HIF1A-mediated therapy in clear cell ovarian cancer [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research; 2019 Sep 13-16, 2019; Atlanta, GA. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(13_Suppl):Abstract nr A67.

Wiebke Bartels, Simon Adamson, Lisa Leung, Don D Sin, Stephan F van Eeden Centre for Heart Lung Innovation, Department of Medicine, University of British Columbia, Vancouver, BC, Canada Rationale: Readmissions are common following acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and are partially responsible for increased morbidity and mortality in COPD. Numerous factors have been shown to predict readmission of patients previously admitted to hospital for AECOPD; however, factors related to readmission in patients who are triaged in emergency departments (EDs) and sent directly home are poorly understood. We postulate that patients seen in the ED for AECOPD and directly sent home have a high readmission rate, and we suspect that inadequate management and follow-up contribute to this high readmission rate. Methods: We conducted a 1-year retrospective study of all patients seen in the ED for AECOPD at an inner-city tertiary care hospital; 30- and 90-day readmission rates for COPD and all-cause admissions to the ED and hospital were determined. Patients discharged directly home from the ED were compared with those admitted to hospital for management. Patient, treatment, and system variables that could potentially impact readmission were documented. Multivariate Poisson regression models were used to determine which factors predicted readmissions. Results: The readmission rates in the ED group (n=240) were significantly higher than that in the hospitalized group (n=271): 1) the 90-day ED readmissions (1.29 vs 0.51, p

Climate change has a drastic impact on the structure and behavior of the amazon. Short-term effects of climate change are gradually creating more long-term effects that can be witnessed globally. Due to increased temperature, decreased precipitation and increased greenhouse gases, the amazon faces hazardous events such as droughts, forest fires, floods and vegetation differences. All of these events contribute to larger scale impacts on the amazon such as a major loss of biodiversity, and ultimately Amazon dieback. Forest feedback loops present the issue of how the Amazon is not only being affected by climate change but also how it is accelerating climate change. The environmental issues also negatively impact those living in the Amazon due to increased disease, famine, social unrest and economic downturn. This report outlines both the short and long-term impacts climate change has on the Amazon region as well as the social and economic impacts experienced by those living within the Amazon.

This article discusses why and how, in October 2013, the struggle for a free-to-air TV license by HKTV could turn into a social movement. It traces the historical makeup of neo-liberalization and monopolization in TV production: TV licensing as a (colonial) governmental measure on the media under the guise of a “laissez-faire” media policy, which has been reinvented as a grip on cultural rights to TV in post-handover Hong Kong. HKTV's “David vs Goliath” struggle against the decision demonstrated how political fear (of Beijing control over the Hong Kong government) among the people has fed into an anxiety over media monopoly. What might have caught the powers-to-be by surprise was the vociferous protest from the general public. My analysis situates the incident in the context of an array of travesties against media freedoms in recent years, which have enabled the audience (as citizens) to rise up and demand their cultural rights to creative and quality TV. I conclude by examining the agency of crea...

Using integrative genomics and functional screening we identified coiled-coil domain containing 68 (CCDC68) as a novel putative tumor suppressor (TSG) in pancreatic ductal adenocarcinoma (PDAC). CCDC68 allelic losses were documented in 48% of primary PDAC patient tumors, 50% of PDAC cell lines, and 30% of primary patient derived xenografts. We also discovered a SNP variant (SNP rs1344011) that leads to exon skipping and generation of an unstable protein isoform CCDC68Δ69–114 in 31% of PDAC patients. Overexpression of full length CCDC68 (CCDC68wt) in PANC-1 and Hs.766T PDAC cell lines lacking CDCC68 expression decreased proliferation and tumorigenicity in scid mice. In contrast, downregulation of endogenous CCDC68 in MIAPaca-2 cells increased tumor growth rate. These effects were not observed with the deletion-containing isoform, CCDC68Δ69–114. In conclusion, our results suggest that CCDC68 is a novel candidate TSG in PDAC.

With the passage of time, technological innovations, different political and societal developments, the definition and forms of political engagements evolve. Facebook has become a form of political engagement that cannot be neglected, often, fostering and reinforcing other forms of political engagements, both new and traditional. The internet has played a transformative role in the development of political engagement and Facebook acts as a catalyst in such transformation. This paper will examine the relation between Facebook and political engagement in Hong Kong. In the semi-democratic, but essentially liberal, Hong Kong, no doubt, Facebook is an emerging indispensible political tool that cannot be undermined within the Hong Kong political arena. Recently, political parties, politicians, activists, those interested in politics in Hong Kong and even the government use the Facebook for different political purposes. It is more common for Hong Kong people to engage in Facebook politically at the cognitive awa...

Summary Background Paper-based estimated food diaries are often used in research to collect dietary data, despite this method being burdensome for both participants and researchers. Such food diaries are often time consuming, labour intensive, and rely on participant literacy and therefore may lead to greater rates of under-reporting. Methods This study assessed the validity of the ‘ Boden Food Plate' , a novel web-based electronic application, compared to a paper-based three-day estimated food diary. Participants were also asked to rate their satisfaction with the new electronic diary. Sixty-seven participants with overweight or obesity completed both the electronic and paper-based diaries at two different time-points. Results Baseline BMI of participants (mean±standard deviation (SD)) was 30.4±2.9kg/m 2 , body weight was 87.6±13.4kg, and age was 42.3±7.7years. Fifty four percent (n=41) of the cohort were female. Bland Altman plots for total energy, and percentage of total energy intake from fat, carbohydrate, and protein, indicated wide limits of agreement between the two methods of dietary data collection, and in some analyses there were a few cases that did not lie within the 95% confidence intervals. Approximately 70% of participants rated the electronic food diary as easier to use and more fun when compared to the traditional paper-based estimated food diary. Conclusion Innovative and visual dietary collection applications such as the ‘Boden Food Plate' provide an enjoyable and interactive means of measuring nutritional intake in a time efficient manner. Further validation studies incorporating micronutrient analysis and to improve the applications validity are warranted.

The article examines the dynamics involved in the mediation of a global event by (local) news media. Using the case study of the WTO conference held in Hong Kong in December 2005, it critiques the discursive practice of 'indigenization' in local news coverage. Specifically, it argues that mediated violence is justified in the framing of a global event. Mediatized conflict is also seen as a process that potentially co-opts conflicting parties in the global event, and as an example of the fluid expansive space between the global and the local. The article also discusses the representation of Korean farmers as the violent 'foreign' other. This 'framing' of the Korean protesters, however, was disrupted by experienced Korean protesters, who forced unwary reporters to change their ritualistic representation of the whole event. This scenario epitomizes one of the problematics involved in the hegemonic interplay between local news media, social movements and politics in the increasingly intensified local/global nexus.

(Transnationalized) popular culture and (global) social movement are often seen as unrelated, if not mutually exclusive. Popular culture is entertaining, consensual but trivial; social movement is serious, idealized and oppositional. Yet the WTO Ministerial Conference, held in Hong Kong in December 2005, saw the Korean protesters' adoption of the theme‐song of a popular Korean television drama, Daejanggeum, as their protest strategy. The Korean protesters had been framed by mainstream Hong Kong media as ‘violent rioters’, but the inclusion of the drama elements helped the protesters advance their cause by gaining instant rapport with the local Hong Kong news media and public/fans (of Korean wave). The impact of celebrity involvement in the WTO was also about an immediate transferal of fan affect, from celebrities to the movement, and to the Korean protesters. This ‘affect mobilization’, becomes important as movement capital, as the effective manipulation of emotions is a key to ‘getting the messa...

Co-productions in film and media have intensified in the age of globalization. This chapter focuses on the various factors at work in the Chinese context, from censorship, to cultural and diplomatic forces that could disrupt co-production efforts and transnational cultural flows. It aims to draws on the precarities of transnational media/cultural circulation, when geopolitics collapses in the popular culture. The rapid extension into the international stage has caused China to capitalize on co-production to advance its film production, but it only thinly veils the state’s entrenched distrust of foreign films as potential “imperialistic” elements that looks set to unsettle and corrupt the minds of its nationals into possible dissenting force. The “Korea ban” was China’s justified act of reprisal, but it could be an excuse to vent out the deep-seated cultural nationalism at force, and a show of force through the self-censorship and self-harming practices.

Summary The morphogenetic field, a fundamental concept of classical embryology, is once again being invoked to describe developmental processes. Because the evolution of adult structures requires the modification of development, the ways in which morphogenetic fields can change over time may yield insights into evolutionary possibilities. We considered how the duplication/multiplication of a morphogenetic field in fruit flies, caused by the previously described obake (obk) mutation, is regulated by genetic and environmental factors. Mutations of genes in the canonical antenna-producing imaginal disc pathway suppressed duplication as expected, although the results suggested that other pathways might also be involved. Overgrowth mutations, expected to increase duplication, actually suppressed it. Mutations in the heat-shock protein gene Hsp83 did not uniformly enhance obk expressivity as hypothesized. Using third chromosomes extracted from wild-derived lines, natural genetic variation for modifiers of obk function was found to be extensive. Larval crowding suppressed the obk phenotype, but there was no evidence of trade-offs between body or head size and arista number. Our results suggest that a complex interplay of genetic and environmental factors in the regulation of fields may be responsible for ample natural variation in the expressivity of adult phenotypes, affording multiple opportunities for selection and evolutionary modification.

KRAS is mutated in ∼40% of colorectal cancer (CRC), and there are limited effective treatments for advanced KRAS mutant CRC. Therefore, it is crucial that downstream mediators of oncogenic KRAS continue to be studied. We identified p190RhoGAP as being phosphorylated in the DLD1 CRC cell line, which expresses a heterozygous KRAS G13D allele, and not in DKO4 in which the mutant allele has been deleted by somatic recombination. We found that a ubiquitous binding partner of p190RhoGAP, p120RasGAP (RasGAP), is expressed in much lower levels in DKO4 cells compared to DLD1, and this expression is regulated by KRAS. Rescue of RasGAP expression in DKO4 rescued Rho pathway activation and partially rescued tumorigenicity in DKO4 cells, indicating that the combination of mutant KRAS and RasGAP expression is crucial to these phenotypes. We conclude that RasGAP is an important effector of mutant KRAS in CRC.

Pancreatic ductal adenocarcinoma (PDAC) is the fourth most common cause of cancer death in North America. Activating KRAS mutations and Smad4 loss occur in approximately 90% and 55% of PDAC, respectively. While their roles in the early stages of PDAC development have been confirmed in genetically modified mouse models, their roles in the multistep malignant transformation of human pancreatic duct cells have not been directly demonstrated. Here, we report that Smad4 represents a barrier in KRAS-mediated malignant transformation of the near normal immortalized human pancreatic duct epithelial (HPDE) cell line model. Marked Smad4 downregulation by shRNA in KRAS (G12V) expressing HPDE cells failed to cause tumorigenic transformation. However, KRAS-mediated malignant transformation occurred in a new HPDE-TGF-β resistant (TβR) cell line that completely lacks Smad4 protein expression and is resistant to the mito-inhibitory activity of TGF-β. This transformation resulted in tumor formation and development of metastatic phenotype when the cells were implanted orthotopically into the mouse pancreas. Smad4 restoration re-established TGF-β sensitivity, markedly increased tumor latency by promoting apoptosis, and decreased metastatic potential. These results directly establish the critical combination of the KRAS oncogene and complete Smad4 inactivation in the multi-stage malignant transformation and metastatic progression of normal human HPDE cells.