Autophosphorylation transforms DNA-PK from protecting to processing DNA ends.

The DNA-dependent protein kinase (DNA-PK) initially protects broken DNA ends but then promotes their processing during non-homologous end joining (NHEJ). Before ligation by NHEJ, DNA hairpin ends generated during V(D)J recombination must be opened by the Artemis nuclease, together with autophosphorylated DNA-PK. Structures of DNA-PK bound to DNA before and after phosphorylation, and in complex with Artemis and a DNA hairpin, reveal an essential functional switch. When bound to open DNA ends in its protection mode, DNA-PK is inhibited for cis-autophosphorylation of the so-called ABCDE cluster but activated for phosphorylation of other targets. In contrast, DNA hairpin ends promote cis-autophosphorylation. Phosphorylation of four Thr residues in ABCDE leads to gross structural rearrangement of DNA-PK, widening the DNA binding groove for Artemis recruitment and hairpin cleavage. Meanwhile, Artemis locks DNA-PK into the kinase-inactive state. Kinase activity and autophosphorylation of DNA-PK are regulated by different DNA ends, feeding forward to coordinate NHEJ events.

Lesion recognition by XPC, TFIIH and XPA in DNA excision repair.

Nucleotide excision repair removes DNA lesions caused by ultraviolet light, cisplatin-like compounds and bulky adducts1. After initial recognition by XPC in global genome repair or a stalled RNA polymerase in transcription-coupled repair, damaged DNA is transferred to the seven-subunit TFIIH core complex (Core7) for verification and dual incisions by the XPF and XPG nucleases2. Structures capturing lesion recognition by the yeast XPC homologue Rad4 and TFIIH in transcription initiation or DNA repair have been separately reported3-7. How two different lesion recognition pathways converge and how the XPB and XPD helicases of Core7 move the DNA lesion for verification are unclear. Here we report on structures revealing DNA lesion recognition by human XPC and DNA lesion hand-off from XPC to Core7 and XPA. XPA, which binds between XPB and XPD, kinks the DNA duplex and shifts XPC and the DNA lesion by nearly a helical turn relative to Core7. The DNA lesion is thus positioned outside of Core7, as would occur with RNA polymerase. XPB and XPD, which track the lesion-containing strand but translocate DNA in opposite directions, push and pull the lesion-containing strand into XPD for verification.

Structure of an activated DNA-PK and its implications for NHEJ.

DNA-dependent protein kinase (DNA-PK), like all phosphatidylinositol 3-kinase-related kinases (PIKKs), is composed of conserved FAT and kinase domains (FATKINs) along with solenoid structures made of HEAT repeats. These kinases are activated in response to cellular stress signals, but the mechanisms governing activation and regulation remain unresolved. For DNA-PK, all existing structures represent inactive states with resolution limited to 4.3 Å at best. Here, we report the cryoelectron microscopy (cryo-EM) structures of DNA-PKcs (DNA-PK catalytic subunit) bound to a DNA end or complexed with Ku70/80 and DNA in both inactive and activated forms at resolutions of 3.7 Å overall and 3.2 Å for FATKINs. These structures reveal the sequential transition of DNA-PK from inactive to activated forms. Most notably, activation of the kinase involves previously unknown stretching and twisting within individual solenoid segments and loosens DNA-end binding. This unprecedented structural plasticity of helical repeats may be a general regulatory mechanism of HEAT-repeat proteins.

Cracking the DNA Code for V(D)J Recombination.

To initiate V(D)J recombination for generating the adaptive immune response of vertebrates, RAG1/2 recombinase cleaves DNA at a pair of recombination signal sequences, the 12- and 23-RSS. We have determined crystal and cryo-EM structures of RAG1/2 with DNA in the pre-reaction and hairpin-forming complexes up to 2.75 Å resolution. Both protein and DNA exhibit structural plasticity and undergo dramatic conformational changes. Coding-flank DNAs extensively rotate, shift, and deform for nicking and hairpin formation. Two intertwined RAG1 subunits crisscross four times between the asymmetric pair of severely bent 12/23-RSS DNAs. Location-sensitive bending of 60° and 150° in 12- and 23-RSS spacers, respectively, must occur for RAG1/2 to capture the nonamers and pair the heptamers for symmetric double-strand breakage. DNA pairing is thus sequence-context dependent and structure specific, which partly explains the "beyond 12/23" restriction. Finally, catalysis in crystallo reveals the process of DNA hairpin formation and its stabilization by interleaved base stacking.

Structural studies of WDR5 in complex with MBD3C WIN motif reveal a unique binding mode.

The nucleosome remodeling and deacetylase (NuRD) complex plays a pivotal role in chromatin regulation and transcriptional repression. In mice, methyl-CpG binding domain 3 isoform C (MBD3C) interacts specifically with the histone H3 binding protein WD repeat-containing protein 5 (WDR5) and forms the WDR5-MBD3C/Norde complex. Despite the functional significance of this interaction on embryonic stem cell gene regulation, the molecular mechanism underlying MBD3C recognition by WDR5 remains elusive. Here, we determined the crystal structure of WDR5 in complex with the peptide (residues 40-51) derived from the MBD3C protein at a resolution of 1.9 Å. Structural analysis revealed that MBD3C utilizes a unique binding mode to interact with WDR5, wherein MBD3C Arg43 and Phe47 are involved in recognizing the WDR5-interacting (WIN) site and Tyr191-related B site on the small surface of WDR5, respectively. Notably, the binding induces a ∼91° rotation of WDR5 Tyr191, generating the hydrophobic B site. Furthermore, mutation experiments combined with isothermal titration calorimetry (ITC) assays confirmed the importance of both Arg43 and Phe47 in mediating WDR5 binding affinity. By determining structures of various peptides bound to WDR5, we demonstrated that the WDR5 WIN site and B site can be concurrently recognized by WIN motif peptides containing ''Arg-Cies/Ser-Arg-Val-Phe'' consensus sequence. Overall, this study reveals the structural basis for the formation of the WDR5-MBD3C subcomplex and provides new insights into the recognition mode of WDR5 for the WIN motif. Moreover, these findings shed light on structural-based designs of WDR5-targeted anti-cancer small molecule inhibitors or peptide-mimic drugs.

Co-evolution-based prediction of metal-binding sites in proteomes by machine learning.

Metal ions have various important biological roles in proteins, including structural maintenance, molecular recognition and catalysis. Previous methods of predicting metal-binding sites in proteomes were based on either sequence or structural motifs. Here we developed a co-evolution-based pipeline named 'MetalNet' to systematically predict metal-binding sites in proteomes. We applied MetalNet to proteomes of four representative prokaryotic species and predicted 4,849 potential metalloproteins, which substantially expands the currently annotated metalloproteomes. We biochemically and structurally validated previously unannotated metal-binding sites in several proteins, including apo-citrate lyase phosphoribosyl-dephospho-CoA transferase citX, an Escherichia coli enzyme lacking structural or sequence homology to any known metalloprotein (Protein Data Bank (PDB) codes: 7DCM and 7DCN ). MetalNet also successfully recapitulated all known zinc-binding sites from the human spliceosome complex. The pipeline of MetalNet provides a unique and enabling tool for interrogating the hidden metalloproteome and studying metal biology.

PITX2 functions as a transcription factor for GPX4 and protects pancreatic cancer cells from ferroptosis.

Ferroptosis inhibits tumor progression in pancreatic cancer cells, while PITX2 is known to function as a pro-oncogenic factor in various tumor types, protecting them from ferroptosis and thereby promoting tumor progression. In this study, we sought to investigate the regulatory role of PITX2 in tumor cell ferroptosis within the context of pancreatic cancer. We conducted PITX2 knockdown experiments using lentiviral infection in two pancreatic cancer cell lines, namely PANC-1 and BxPC-3. We assessed protein expression through immunoblotting and mRNA expression through RT-PCR. To confirm PITX2 as a transcription factor for GPX4, we employed Chromatin Immunoprecipitation (ChIP) and Dual-luciferase assays. Furthermore, we used flow cytometry to measure reactive oxygen species (ROS), lipid peroxidation, and apoptosis and employed confocal microscopy to assess mitochondrial membrane potential. Additionally, electron microscopy was used to observe mitochondrial structural changes and evaluate PITX2's regulation of ferroptosis in pancreatic cancer cells. Our findings demonstrated that PITX2, functioning as a transcription factor for GPX4, promoted GPX4 expression, thereby exerting an inhibitory effect on ferroptosis in pancreatic cancer cells and consequently promoting tumor progression. Moreover, PITX2 enhanced the invasive and migratory capabilities of pancreatic cancer cells by activating the WNT signaling pathway. Knockdown of PITX2 increased ferroptosis and inhibited the proliferation of PANC-1 and BxPC-3 cells. Notably, the inhibitory effect on ferroptosis resulting from PITX2 overexpression in these cells could be countered using RSL3, an inhibitor of GPX4. Overall, our study established PITX2 as a transcriptional regulator of GPX4 that could promote tumor progression in pancreatic cancer by reducing ferroptosis. These findings suggest that PITX2 may serve as a potential therapeutic target for combating ferroptosis in pancreatic cancer.

Effect of Laparoscopic and Open Pancreaticoduodenectomy for Pancreatic or Periampullary Tumors: Three-year Follow-up of a Randomized Clinical Trial.

OBJECTIVE: This study aimed to estimate whether the potential short-term advantages of laparoscopic pancreaticoduodenectomy (LPD) could allow patients to recover in a more timely manner and achieve better long-term survival than with open pancreaticoduodenectomy (OPD) in patients with pancreatic or periampullary tumors. BACKGROUND: LPD has been demonstrated to be feasible and may have several potential advantages over OPD in terms of shorter hospital stay and accelerated recovery than OPD. METHODS: This noninferiority, open-label, randomized clinical trial was conducted in 14 centers in China. The initial trial included 656 eligible patients with pancreatic or periampullary tumors enrolled from May 18, 2018, to December 19, 2019. The participants were randomized preoperatively in a 1:1 ratio to undergo either LPD (n=328) or OPD (n=328). The 3-year overall survival (OS), quality of life, which was assessed using the 3-level version of the European Quality of Life-5 Dimensions, depression, and other outcomes were evaluated. RESULTS: Data from 656 patients [328 men (69.9%); mean (SD) age: 56.2 (10.7) years] who underwent pancreaticoduodenectomy were analyzed. For malignancies, the 3-year OS rates were 59.1% and 54.3% in the LPD and OPD groups, respectively ( P =0.33, hazard ratio: 1.16, 95% CI: 0.86-1.56). The 3-year OS rates for others were 81.3% and 85.6% in the LPD and OPD groups, respectively ( P =0.40, hazard ratio: 0.70, 95% CI: 0.30-1.63). No significant differences were observed in quality of life, depression and other outcomes between the 2 groups. CONCLUSION: In patients with pancreatic or periampullary tumors, LPD performed by experienced surgeons resulted in a similar 3-year OS compared with OPD. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03138213.

Comprehensive Analysis of the Immunosuppressive Function of Regulatory T Cells in Human Hepatocellular Carcinoma Tissues.

BACKGROUND: Immune-based therapies are commonly employed to combat hepatocellular carcinoma (HCC). However, the presence of immune-regulating elements, especially regulatory T cells (Tregs), can dramatically impact the treatment efficacy. A deeper examination of the immune-regulation mechanisms linked to these inhibitory factors and their impact on HCC patient outcomes is warranted. METHODS: We employed multicolor fluorescence immunohistochemistry (mIHC) to stain Foxp3, cytokeratin, and nuclei on an HCC tissue microarray (TMA). Leveraging liver cancer transcriptome data from TCGA, we built a prognostic model focused on Treg-associated gene sets and represented it with a nomogram. We then sourced liver cancer single-cell RNA sequencing data (GSE140228) from the GEO database, selectively focusing on Treg subsets, and conducted further analyses, including cell-to-cell communication and pseudo-time trajectory examination. RESULTS: Our mIHC results revealed a more substantial presence of Foxp3+Tregs in HCC samples than in adjacent normal tissue samples (P < .001). An increased presence of Foxp3+Tregs in HCC samples correlated with unfavorable patient outcomes (HR = 1.722, 95% CI:1.023-2.899, P = .041). The multi-factorial prognosis model we built from TCGA liver cancer data highlighted Tregs as a standalone risk determinant for predicting outcomes (HR = 3.84, 95% CI:2.52-5.83, P < .001). Re-analyzing the scRNA-seq dataset (GSE140228) showcased distinctive gene expression patterns in Tregs from varying tissues. Interactions between Tregs and other CD4+T cell types were predominantly governed by the CXCL13/CXCR3 signaling pathway. Communication pathways between Tregs and macrophages primarily involved MIF-CD74/CXCR4, LGALS9/CD45, and PTPRC/MRC1. Additionally, macrophages could influence Tregs via HLA-class II and CD4 interactions. CONCLUSION: An elevated presence of Tregs in HCC samples correlated with negative patient outcomes. Elucidating the interplay between Tregs and other immune cells in HCC could provide insights into the modulatory role of Tregs within HCC tissues.

Electronic Structure Modulation Via Iron-Incorporated NiO to Boost Urea Oxidation/Oxygen Evolution Reaction.

The urea-assisted water splitting not only enables a reduction in energy consumption during hydrogen production but also addresses the issue of environmental pollution caused by urea. Doping heterogeneous atoms in Ni-based electrocatalysts is considered an efficient means for regulating the electronic structure of Ni sites in catalytic processes. However, the current methodologies for synthesizing heteroatom-doped Ni-based electrocatalysts exhibit certain limitations, including intricate experimental procedures, prolonged reaction durations, and low product yield. Herein, Fe-doped NiO electrocatalysts were successfully synthesized using a rapid and facile solution combustion method, enabling the synthesis of 1.1107 g within a mere 5 min. The incorporation of iron atoms facilitates the modulation of the electronic environment around Ni atoms, generating a substantial decrease in the Gibbs free energy of intermediate species for the Fe-NiO catalyst. This modification promotes efficient cleavage of C-N bonds and consequently enhances the catalytic performance of UOR. Benefiting from the tunability of the electronic environment around the active sites and its efficient electron transfer, Fe-NiO electrocatalysts only needs 1.334 V to achieve 50 mA cm-2 during UOR. Moreover, Fe-NiO catalysts were integrated into a dual electrode urea electrolytic system, requiring only 1.43 V of cell voltage at 10 mA cm-2.

Analysis of factors influencing pancreatic fistula after minimally invasive pancreaticoduodenectomy and establishment of a new prediction model for clinically relevant pancreatic fistula.

BACKGROUND: Postoperative pancreatic fistula (POPF) is the most prevalent complications following minimally invasive pancreaticoduodenectomy (MIPD). Only one model related to MIPD exists, and previous POPF scoring prediction methods are based on open pancreaticoduodenectomy patients. Our objectives are to determine the variables that may increase the probability of pancreatic fistula following MIPD and to develop and validate a POPF predictive risk model. METHODS: Data from 432 patients who underwent MIPD between July 2015 and May 2022 were retrospectively collected. A nomogram prediction model was created using multivariate logistic regression analysis to evaluate independent factors for POPF in patients undergoing MIPD in the modeling cohort. The area under the curve (AUC) of the receiver operating characteristic curve (ROC) and the calibration curve were used to verify the nomogram prediction model internally and externally within the modeling cohort and the verification cohort. RESULTS: Multivariate logistic regression analysis showed that body mass index (BMI), albumin, triglycerides, pancreatic duct diameter, pathological diagnosis and intraoperative bleeding were independent variables for POPF. On the basis of this information, a model for the prediction of risks associated with POPF was developed. In accordance with the ROC analysis, the modeling cohort's AUC was 0.819 (95% CI 0.747-0.891), the internal validation cohort's AUC was 0.830 (95% CI 0.747-0.912), and the external validation cohort's AUC was 0.793 (95% CI 0.671-0.915). Based on the calibration curve, the estimated values of POPF have a high degree of concordance with the actual values that were measured. CONCLUSIONS: This model for predicting the probability of pancreatic fistula following MIPD has strong predictive capacity and can provide a trustworthy predictive method for the early screening of high-risk patients with pancreatic fistula after MIPD and timely clinical intervention.

Diesel degradation capability and environmental robustness of strain Pseudomonas aeruginosa WS02.

Petroleum hydrocarbon (PHC) degrading bacteria have been frequently discovered. However, in practical application, a single species of PHC degrading bacterium with weak competitiveness may face environmental pressure and competitive exclusion due to the interspecific competition between petroleum-degrading bacteria as well as indigenous microbiota in soil, leading to a reduced efficacy or even malfunction. In this study, the diesel degradation ability and environmental robustness of an endophytic strain Pseudomonas aeruginosa WS02, were investigated. The results show that the cell membrane surface of WS02 was highly hydrophobic, and the strain secreted glycolipid surfactants. Genetic analysis results revealed that WS02 contained multiple metabolic systems and PHC degradation-related genes, indicating that this strain theoretically possesses the capability of oxidizing both alkanes and aromatic hydrocarbons. Gene annotation also showed many targets which coded for heavy metal resistant and metal transporter proteins. The gene annotation-based inference was confirmed by the experimental results: GC-MS analysis revealed that short chain PHCs (C10-C14) were completely degraded, and the degradation of PHCs ranging from C15-C22 were above 90% after 14 d in diesel-exposed culture; Heavy metal (Mn2+, Pb2+ and Zn2+) exposure was found to affect the growth of WS02 to some extent, but not its ability to degrade diesel, and the degradation efficiency was still maintained at 39-59%. WS02 also showed a environmental robustness along with PHC-degradation performance in the co-culture system with other bacterial strains as well as in the co-cultured system with the indigenous microbiota in soil fluid extracted from a PHC-contaminated site. It can be concluded that the broad-spectrum diesel degradation efficacy and great environmental robustness give P. aeruginosa WS02 great potential for application in the remediation of PHC-contaminated soil.

Maximum Value on Arterial Phase Computed Tomography Predicts Prognosis and Treatment Efficacy of Sunitinib for Pancreatic Neuroendocrine Tumours.

PURPOSE: This study was designed to assess the computed tomography maximum (CTmax) value on pretherapeutic arterial phase computed tomography (APCT) images to predict pancreatic neuroendocrine tumours (pNETs) recurrence and clarify its role in predicting the outcome of tumour therapy. METHODS: This retrospective study enrolled 250 surgical patients and 24 nonsurgical patients with sunitinib-based treatment in our hospital from 2008 to 2019. CT images were assessed, the maximum value was defined as "CTmax," and recurrence-free survival (RFS) or progression-free survival (PFS) was compared between a high-CTmax group and a low-CTmax group among patients who underwent surgical resection or nonsurgical, sunitinib-based treatment according to the CTmax cutoff value. RESULTS: In ROC curve analysis, a CTmax of 108 Hounsfield units, as the cutoff value, achieved an AUC of 0.796 in predicting recurrence. Compared with the low-CTmax group, the high-CTmax group had a longer RFS (p < 0.001). Low CTmax was identified as an independent factor for RFS (p < 0.001) in multivariate analysis; these results were confirmed using the internal validation set. The CTmax value was significantly correlated with the microvascular density (MVD) value (p < 0.001) and the vascular endothelial growth factor receptor 2 (VEGFR2) score (p < 0.001). Furthermore, the high-CTmax group had a better PFS than the low-CTmax group among the sunitinib treatment group (p = 0.007). CONCLUSIONS: The tumour CTmax on APCT might be a potential and independent indicator for predicting recurrence in patients who have undergone surgical resection and assessing the efficacy of sunitinib for patients with advanced metastatic pNETs.

The Long-Term Outcome of Laparoscopic Resection for Perihilar Cholangiocarcinoma Compared with the Open Approach: A Real-World Multicentric Analysis.

OBJECTIVE: The aim of this study was to compare the short- and long-term outcomes of laparoscopic surgery (LS) and open surgery (OP) for perihilar cholangiocarcinoma (PHC) using a large real-world dataset in China. METHODS: Data of patients with PHC who underwent LS and OP from January 2013 to October 2018, across 10 centers in China, were extracted from medical records. A comparative analysis was performed before and after propensity score matching (PSM) in the LS and OP groups and within the study subgroups. The Cox proportional hazards mixed-effects model was applied to estimate the risk factors for mortality, with center and year of operation as random effects. RESULTS: A total of 467 patients with PHC were included, of whom 161 underwent LS and 306 underwent OP. Postoperative morbidity, such as hemorrhage, biliary fistula, abdominal abscess, and hepatic insufficiency, was similar between the LS and OP groups. The median overall survival (OS) was longer in the LS group than in the OP group (NA vs. 22 months; hazard ratio [HR] 1.19, 95% confidence interval [CI] 1.02-1.39, p = 0.024). Among the matched datasets, OS was comparable between the LS and OP groups (NA vs. 35 months; HR 0.99, 95% CI 0.77-1.26, p = 0.915). The mixed-effect model identified that the surgical method was not associated with long-term outcomes and that LS and OP provided similar oncological outcomes. CONCLUSIONS: Considering the comparable long-term prognosis and short-term outcomes of LS and OP, LS could be a technically feasible surgical method for PHC patients with all Bismuth-Corlett types of PHC.

SETD8 inhibits ferroptosis in pancreatic cancer by inhibiting the expression of RRAD.

BACKGROUND: As an oncogene, SETD8 can promote tumour growth and tumour cell proliferation. This study aims to reveal the relationship between SETD8 and ferroptosis in pancreatic cancer and its role in pancreatic cancer to provide a possible new direction for the comprehensive treatment of pancreatic cancer. METHODS: The downstream targets were screened by RNA sequencing analysis. Western blot, Real-time Quantitative PCR (qPCR) and immunohistochemistry showed the relationship between genes. Cell proliferation analysis and cell metabolite analysis revealed the function of genes. Chromatin immunoprecipitation (CHIP) assays were used to study the molecular mechanism. RESULTS: The potential downstream target of SETD8, RRAD, was screened by RNA sequencing analysis. A negative correlation between SETD8 and RRAD was found by protein imprinting, Real-time Quantitative PCR (qPCR) and immunohistochemistry. Through cell proliferation analysis and cell metabolite analysis, it was found that RRAD can not only inhibit the proliferation of cancer cells but also improve the level of lipid peroxidation of cancer cells. At the same time, chromatin immunoprecipitation analysis (CHIP) was used to explore the molecular mechanism by which SETD8 regulates RRAD expression. SETD8 inhibited RRAD expression. CONCLUSIONS: SETD8 interacts with the promoter region of RRAD, which epigenetically silences the expression of RRAD to reduce the level of lipid peroxidation in pancreatic cancer cells, thereby inhibiting ferroptosis in pancreatic cancer cells and resulting in poor prognosis of pancreatic cancer.

Laparoscopic versus open surgery for perihilar cholangiocarcinoma: a multicenter propensity score analysis of short- term outcomes.

BACKGROUND: Laparoscopic surgery (LS) has been increasingly applied in perihilar cholangiocarcinoma (pCCA). In this study, we intend to compare the short-term outcomes of LS versus open operation (OP) for pCCA in a multicentric practice in China. METHODS: This real-world analysis included 645 pCCA patients receiving LS and OP at 11 participating centers in China between January 2013 and January 2019. A comparative analysis was performed before and after propensity score matching (PSM) in LS and OP groups, and within Bismuth subgroups. Univariate and multivariate models were performed to identify significant prognostic factors of adverse surgical outcomes and postoperative length of stay (LOS). RESULTS: Among 645 pCCAs, 256 received LS and 389 received OP. Reduced hepaticojejunostomy (30.89% vs 51.40%, P = 0.006), biliary plasty requirement (19.51% vs 40.16%, P = 0.001), shorter LOS (mean 14.32 vs 17.95 d, P < 0.001), and lower severe complication (CD ≥ III) (12.11% vs. 22.88%, P = 0.006) were observed in the LS group compared with the OP group. Major postoperative complications such as hemorrhage, biliary fistula, abdominal abscess, and hepatic insufficiency were similar between LS and OP (P > 0.05 for all). After PSM, the short-term outcomes of two surgical methods were similar, except for shorter LOS in LS compared with OP (mean 15.19 vs 18.48 d, P = 0.0007). A series subgroup analysis demonstrated that LS was safe and had advantages in shorting LOS. CONCLUSION: Although the complex surgical procedures, LS generally seems to be safe and feasible for experienced surgeons. TRIAL REGISTRATION: NCT05402618 (date of first registration: 02/06/2022).

A new glance at autophagolysosomal-dependent or -independent function of transcriptional factor EB in human cancer.

Autophagy-lysosome system plays a variety of roles in human cancers. In addition to being implicated in metabolism, it is also involved in tumor immunity, remodeling the tumor microenvironment, vascular proliferation, and promoting tumor progression and metastasis. Transcriptional factor EB (TFEB) is a major regulator of the autophagy-lysosomal system. With the in-depth studies on TFEB, researchers have found that it promotes various cancer phenotypes by regulating the autophagolysosomal system, and even in an autophagy-independent way. In this review, we summarize the recent findings about TFEB in various types of cancer (melanoma, pancreatic ductal adenocarcinoma, renal cell carcinoma, colorectal cancer, breast cancer, prostate cancer, ovarian cancer and lung cancer), and shed some light on the mechanisms by which it may serve as a potential target for cancer treatment.

Development and validation of an RBP gene signature for prognosis prediction in colorectal cancer based on WGCNA.

BACKGROUND: RNA binding proteins (RBPs) have been implicated in oncogenesis and progression in various cancers. However, the potential value of RBPs as prognostic indicators and therapeutic targets in colorectal cancer (CRC) requires further investigation. METHODS: Four thousand eighty two RBPs were collected from literature. The weighted gene co-expression network analysis (WGCNA) was performed to identify prognosis-related RBP gene modules based on the data attained from the TCGA cohorts. LASSO algorithm was conducted to establish a prognostic risk model, and the validity of the proposed model was confirmed by an independent GEO dataset. Functional enrichment analysis was performed to reveal the potential biological functions and pathways of the signature and to estimate tumor immune infiltration. Potential therapeutic compounds were inferred utilizing CMap database. Expressions of hub genes were further verified through the Human Protein Atlas (HPA) database and RT-qPCR. RESULTS: One thousand seven hundred thirty four RBPs were differently expressed in CRC samples and 4 gene modules remarkably linked to the prognosis were identified, based on which a 12-gene signature was established for prognosis prediction. Multivariate Cox analysis suggested this signature was an independent predicting factor of overall survival (P < 0.001; HR:3.682; CI:2.377-5.705) and ROC curves indicated it has an effective predictive performance (1-year AUC: 0.653; 3-year AUC:0.673; 5-year AUC: 0.777). GSEA indicated that high risk score was correlated with several cancer-related pathways, including cytokine-cytokine receptor cross talk, ECM receptor cross talk, HEDGEHOG signaling cascade and JAK/STAT signaling cascade. ssGSEA analysis exhibited a significant correlation between immune status and the risk signature. Noscapine and clofazimine were screened as potential drugs for CRC patients with high-risk scores. TDRD5 and GPC1 were identified as hub genes and their expression were validated in 15 pairs of surgically resected CRC tissues. CONCLUSION: Our research provides a depth insight of RBPs' role in CRC and the proposed signature are helpful to the personalized treatment and prognostic judgement.

PITX2 in pancreatic stellate cells promotes EMT in pancreatic cancer cells via the Wnt/ß-catenin pathway.

Since the prognosis of patients with pancreatic cancer is very poor and there is a lack of treatment methods, this study is performed to investigate the function of PITX2 in pancreatic stellate cells (PSCs) in the progression of pancreatic cancer. Scientific hypotheses are proposed according to bioinformatics analysis and tissue microarray analysis. Stable knockdown of PITX2 in PSCs is achieved through lentiviral infection. The relative expressions of PITX2, α-SMA, vimentin, CTNNB1, AXIN1 and LEF1 are measured in wild-type PSCs and PITX2-knockdown PSCs. Proliferative capacity is measured by EdU assay. After coculture with PSCs, the proliferation, invasion and migration capacity of pancreatic cancer cells are tested. EMT and Wnt/ß-catenin downstream genes of pancreatic cancer cells are investigated to reveal the potential mechanism. Bioinformatics analysis reveals that the PITX2 gene is highly expressed in stromal cells in pancreatic cancer and is correlated with squamous-type PDAC. Analysis of PDAC tissue microarray further demonstrates that high PITX2 level in stromal cells is correlated with poor prognosis in PDAC. After stable knockdown of PITX2 in PSCs, the relative protein levels of α-SMA, vimentin, CTNNB1, AXIN1 and LEF1 are decreased, and the proliferative capacity of PSCs is also decreased. After coculture with PSCs, in which PITX2 expression is downregulated, the proliferation, invasion and migration capacities of pancreatic cancer cells are inhibited. Thus, our results show that PITX2-silenced PSCs inhibit the growth, migration and invasion of pancreatic cancer cells via reduced EMT and Wnt/ß-catenin signaling.

Clinical outcomes of minimally invasive duodenum-preserving pancreatic head resection.

BACKGROUND: The procedure of total duodenum-preserving pancreatic head resection (DPPHRt) has been reported frequently, but rare in minimally invasive procedure, especially robotic-assisted operation. Here we share our experience and analyze the clinical outcomes of minimally invasive DPPHRt in the treatment of benign lesions or low-grade malignant tumors of the pancreatic head in this study. MATERIALS AND METHODS: From October 2016 to January 2022, three patients received robot-assisted DPPHRt(RA-DPPHRt), and seventeen patients received laparoscopic DPPHRt(LDPPHRt). Data were retrospectively collected in terms of demographic characteristics (age, gender, body mass index, and pathological diagnosis), intraoperative variables (operative time, estimated blood loss), and post-operative variables (post-operative hospital stay, and complications). RESULTS: All 20 patients received minimally invasive total duodenum-preserving pancreatic head resection successfully without conversion, including 8 males and 12 females. Pathological diagnosis suggested 1 case of serous cystadenoma (SCA), 4 cases of intraductal papillary mucinous neoplasm (IPMN) ,5 cases of mucinous cystic neoplasm (MCN), 4 cases of pancreatic neuroendocrine neoplasm (PNET), 2 cases of chronic pancreatitis (CP),4 case of solid pseudopapillary tumor (SPT). The average operation time was (285.35 ± 95.13 min), ranging from 95 to 420 min. The average estimate blood loss was (196.50 ± 174.45ml) ,ranging from 10 to 600ml.The average post-operative hospital stay was(20.90 ± 14.44days),ranging from 8 to 54 days. Postoperative complications occurred in 10 patients (50%). A total of 5 patients (20%) suffered grade B or C pancreatic fistula. Two patients (10%) suffered from biliary fistula. Two patients (10%) suffered from delayed gastric emptying. One patient (5%) suffered from abdominal bleeding. The 90-day mortality was 0. No patient was observed tumor recurrence and new-onset diabetes but one developed diarrhea. CONCLUSION: RA-DPPHRt or LDPPHRt provided a minimally invasive approach with good organ-preservation for patients with benign and low-grade malignant pancreatic head tumor. It is only recommended to be performed in high-volume pancreatic centers by experienced pancreatic surgeons.