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Background: Tumors involving the main pancreatic duct (MPD) used to be a contraindication for enucleation. Methods: Clinical data of consecutive patients with pancreatic tumors who received laparoscopic or robotic enucleation (LEN or REN) between January 2019 and December 2021 at Fudan University Shanghai Cancer Center were analyzed. Results: Ninety-six patients were included in the analysis, with 55 in the LEN group and 41 in the REN group, and no conversion to laparotomy. Most tumors were located in the head of pancreas (71.9 %). The tumor diameter (3.1 vs. 1.9 cm) was larger, and more cystic tumors (92.7 % vs. 56.4 %) and more tumors involving the MPD (34.1 % vs. 3.6 %) were observed in the REN group. MPD support tube insertion was performed in 15 cases, with 11 in the REN group and 4 in the LEN group. The incidence of biochemical and grade B postoperative pancreatic fistula (POPF) was both 46.9 %, and no grade C POPF occurred. Among the 45 patients with grade B POPF, 28 cases (62.2 %) were due to carrying drainage tube >3 weeks without additional treatment, and only 4 cases required invasive treatment. For patients with MPD support tube implantation (n = 15), support tube fall-offs were observed in 12 cases, 2 patients had MPD dilatation, and no MPD stricture, stone formation or pancreatic atrophy was observed during follow-up. Conclusions: The incidence of POPF was high but still controllable without serious complications after minimally invasive enucleation. The MPD is no longer a restricted area, and the robotic system has advantages in handling complex enucleations.

Summary: Tumor-suppressive cell competition (TSCC) is a conserved surveillance mechanism in which neighboring cells actively eliminate oncogenic cells. Despite overwhelming studies showing that the unfolded protein response (UPR) is dysregulated in various tumors, it remains debatable whether the UPR restrains or promotes tumorigenesis. Here, using Drosophila eye epithelium as a model, we uncover a surprising decisive role of the Ire1 branch of the UPR in regulating cell polarity gene scribble (scrib) loss-induced TSCC. Both mutation and hyperactivation of Ire1 accelerate elimination of scrib clones via inducing apoptosis and autophagy, respectively. Unexpectedly, relative Ire1 activity is also crucial for determining loser cell fate, as dysregulating Ire1 signaling in the surrounding healthy cells reversed the “loser” status of scrib clones by decreasing their apoptosis. Furthermore, we show that Ire1 is required for cell competition in mammalian cells. Together, these findings provide molecular insights into scrib-mediated TSCC and highlight Ire1 as a key determinant of loser cell fate.

There is striking racial disparity in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates in the United States. We hypothesize that the disparity is significantly smaller in areas with a higher ratio of green spaces. County level data on the SARS-CoV-2 infection rates of black and white individuals in 135 of the most urbanized counties across the United States were collected. The total population in these counties is 132,350,027, comprising 40.3% of the U.S. population. The ratio of green spaces by land-cover type in each county was extracted from satellite imagery. A hierarchical regression analysis measured cross-sectional associations between racial disparity in infection rates and green spaces, after controlling for socioeconomic, demographic, pre-existing chronic disease, and built-up area factors. We found a higher ratio of green spaces at the county level is significantly associated with a lower racial disparity in infection rates. Four types of green space have significant negative associations with the racial disparity in SARS-CoV-2 infection rates. A theoretical model with five core mechanisms and one circumstantial mechanism is presented to interpret the findings.

FBW7 functions as a tumor suppressor by targeting oncoproteins for degradation. Our previous study found FBW7 was low expressed in pancreatic cancer due to sustained activation of Ras-Raf-MEK-ERK pathway, which destabilized FBW7 by phosphorylating at Thr205. MicroPET/CT imaging results revealed that FBW7 substantially decreased 18F-fluorodeoxyglucose uptake in xenograft tumors. Mechanistically, FBW7 inhibited glucose metabolism via c-Myc/TXNIP axis. But in these studies, we observed FBW7 down-regulated genes were widely involved in redox reaction and lipid metabolism. Here we reanalyzed previous gene expression profiling and conducted targeted cell metabolites analysis. Results revealed that FBW7 regulated lipid peroxidation and promoted ferroptosis, a non-apoptotic form of cell death. Mechanistically, we found FBW7 inhibited the expression of stearoyl-CoA desaturase (SCD1) via inhibiting nuclear receptor subfamily 4 group A member 1 (NR4A1). SCD1 was reported to inhibit both ferroptosis and apoptosis, which was consistent with the function of FBW7 and NR4A1, another FBW7 down-regulated gene in the gene expression profiling. Moreover, FBW7 potentiated cytotoxic effect of gemcitabine via activating ferroptosis and apoptosis. Combination ferroptosis inducers and apoptosis activators could also significantly potentiated cytotoxic effect of gemcitabine in pancreatic cancer. Therefore, our findings might provide new strategies for the comprehensive treatment of pancreatic cancer.