Summary Gastric cancer is the fourth most common cancer globally, and is the second most common cause of death from cancer worldwide. About three-quarters of newly diagnosed cases in 2008 were from ...Asian countries. With a high mortality-to-incidence ratio, management of gastric cancer is challenging. We discuss evidence for optimum management of gastric cancer in aspects of screening and early detection, diagnosis, and staging; endoscopic and surgical intervention; and the concepts of perioperative, postoperative, and palliative chemotherapy and use of molecularly targeted therapy. Recommendations are formulated on the basis of the framework provided by the Breast Health Global Initiative, using the categories of basic, limited, enhanced, and maximum level. We aim to provide a stepwise strategy for management of gastric cancer applicable to different levels of health-care resources in Asian countries.
Poly‐ADP‐ribose polymerase (PARP) inhibitors (PARPi) have shown great promise for treating BRCA‐deficient tumors. However, over 40% of BRCA‐deficient patients fail to respond to PARPi. Here, we ...report that thioparib, a next‐generation PARPi with high affinity against multiple PARPs, including PARP1, PARP2, and PARP7, displays high antitumor activities against PARPi‐sensitive and ‐resistant cells with homologous recombination (HR) deficiency both in vitro and in vivo. Thioparib treatment elicited PARP1‐dependent DNA damage and replication stress, causing S‐phase arrest and apoptosis. Conversely, thioparib strongly inhibited HR‐mediated DNA repair while increasing RAD51 foci formation. Notably, the on‐target inhibition of PARP7 by thioparib‐activated STING/TBK1‐dependent phosphorylation of STAT1, triggered a strong induction of type I interferons (IFNs), and resulted in tumor growth retardation in an immunocompetent mouse model. However, the inhibitory effect of thioparib on tumor growth was more pronounced in PARP1 knockout mice, suggesting that a specific PARP7 inhibitor, rather than a pan inhibitor such as thioparib, would be more relevant for clinical applications. Finally, genome‐scale CRISPR screening identified PARP1 and MCRS1 as genes capable of modulating thioparib sensitivity. Taken together, thioparib, a next‐generation PARPi acting on both DNA damage response and antitumor immunity, serves as a therapeutic potential for treating hyperactive HR tumors, including those resistant to earlier‐generation PARPi.
Synopsis
PARP inhibitors (PARPi) resistance is ubiquitous in the clinic. A newly discovered pan‐PARP inhibitor, thioparib, is highly effective against olaparib‐resistant cancer models, which suggests that therapeutic vulnerabilities still exist in PARPi‐resistant tumors.
Thioparib is a novel, potent, and orally bioavailable pan‐PARP inhibitor.
Thioparib overcomes primary and acquired olaparib resistance in vitro and in vivo.
Thioparib suppresses HR‐mediated DNA repair.
Thioparib induces a robust type I interferon response.
PARP inhibitors (PARPi) resistance is ubiquitous in the clinic. A newly discovered pan‐PARP inhibitor, thioparib, is highly effective against olaparib‐resistant cancer models, which suggests that therapeutic vulnerabilities still exist in PARPi‐resistant tumors.
Cancer stem cells (CSCs) are considered responsible for the recurrence and chemoresistance of cancer. Dysregulated autophagy is highly prevalent in many types of cancer including pancreatic cancer ...and has been implicated in cytoprotection and tumor promotion. This study aimed to investigate the role of autophagy in regulating cancer stemness and chemoresistance of pancreatic cancer.
The correlation between autophagy and CSCs and its clinical significance were analyzed using pancreatic cancer tissue microarrays. Genetic and pharmacological approaches were applied to explore the function of autophagy on CSC activity and gemcitabine resistance of pancreatic cancer cells in vitro and in vivo.
LC3 expression positively correlated with the expression of CSC markers aldehyde dehydrogenase 1 (ALDH1), CD44, and CD133 in pancreatic cancer tissues. High coexpression of LC3/ALDH1 was associated with both poor overall survival and progression-free survival. In pancreatic cancer cell lines, higher LC3-II expression was observed in the sphere-forming cells than in the bulk cells. Blockade of autophagy by silencing ATG5, ATG7, and BECN1 or the administration of autophagy inhibitor chloroquine markedly reduced the CSC populations, ALDH1 activity, sphere formation, and resistance to gemcitabine in vitro and in vivo. Furthermore, osteopontin (OPN) was found to stimulate LC3-II, ALDH1, CD44, and CD133 expression in PANC-1 cells, whereas this effect could be prevented by OPN knockdown and autophagy blockade. After treatment with various inhibitors against the major signaling pathways downstream of OPN, only the inhibitor of NF-κB activation, BAY 1170-82, could effectively counteract OPN-induced autophagy and CSC activity. According to the histochemical results, pancreatic cancer patients manifesting high levels of OPN/LC3/ALDH1 and OPN/CD44/CD133 had poor survival.
Induction of autophagy mediated by OPN/NF-κB signaling is required for maintenance of pancreatic CSC activity. Combination of gemcitabine with pharmacological autophagy inhibitors is a promising therapeutic strategy for pancreatic cancer.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Liposomal irinotecan plus 5-fluorouracil/leucovorin (nal-IRI + 5-FU/LV) has shown to provide survival benefits for patients with gemcitabine-refractory metastatic pancreatic ductal adenocarcinoma ...(PDAC) in NAPOLI-1 trial, in which Asian patients experienced more hematological toxicity and subsequent dose modification. A retrospective chart review to investigate the administration pattern, therapeutic efficacy and safety profile of nal-IRI + 5-FU/LV in 44 consecutive patients with gemcitabine-refractory advanced PDAC treated between December 2016 and December 2018 in National Cheng Kung University Hospital, Taiwan. Most of them had metastatic diseases (88.6%), one-line of prior treatment (72.7%), ECOG PS 0-1 (72.7%) and starting dose of nal-IRI at 60 mg/m
(≈52 mg/m
irinotecan free-base) in 65.9%. The overall response rate was 9.1%. The median OS was 6.6 months for the entire cohort, and 7.8 and 2.7 months for patients of ECOG PS 0-1 and>2, respectively. The median OS of ECOG PS 0-1 patients with nal-IRI starting doses at 80 mg/m
(≈70 mg/m
irinotecan free-base, n = 13) and 60 mg/m
(n = 19) were 7.5 and 8.4 months, respectively. Thirty-four percent of patients experienced manageable grade 3-4 hematological toxicity. Our results confirm the clinical benefit of nal-IRI + 5-FU/LV for patients of gemcitabine-refractory advanced PDAC with good performance status in a real-world setting.
Cancer immunotherapy targeting immune checkpoints has exhibited promising clinical outcomes in many cancers, but it offers only limited benefits for pancreatic cancer (PC). Cancer stem cells (CSCs), ...a minor subpopulation of cancer cells, play important roles in tumor initiation, progression, and drug resistance. Accumulating evidence suggests that CSCs employ immunosuppressive effects to evade immune system recognition. However, the clinical implications of the associations among CD8⁺ T cells infiltration, programmed death receptor ligand-1 (PD-L1) expression, and CSCs existence are poorly understood in PC. Immunostaining and quantitative analysis were performed to assess CD8⁺ T cells infiltration, PD-L1 expression, and their relationship with CD44⁺/CD133⁺ CSCs and disease progression in PC. CD8⁺ T cells infiltration was associated with better survival while PD-L1 expression was correlated with PC recurrence. Both the low CD8⁺ T cells infiltration/high PD-L1 expression group and the high CD8⁺ T cells infiltration/high PD-L1 expression group show high levels of CD44⁺/CD133⁺ CSCs, but patients with low CD8⁺ T cells infiltration/high PD-L1 expression had worse survival and higher recurrence risk than those with high CD8⁺ T cells infiltration/high PD-L1 expression. Moreover, high infiltration of CD8⁺ T cells could reduce unfavorable prognostic effect of high co-expression of PD-L1 and CD44/CD133. Our study highlights an interaction among CD8⁺ T cells infiltration, PD-L1 expression, and CD44⁺/CD133⁺ CSCs existence, which contributes to PC progression and immune evasion.
The incidence of neuroendocrine tumors (NETs) has been increasing in recent decades. Previously, we reported the incidence and survival of NETs in Taiwan by analyzing the 1996-2008 data from the ...Taiwan Cancer Registry. Here we performed an updated analysis on the incidence and survival of NETs in Taiwan from 1996 to 2015. The incidence of NETs was 0.244 per 100,000 in 1996 and increased to 3.162 per 100,000 in 2015. The most common site of NETs was rectum (29.65%), followed by lung/bronchus (17.22%), and pancreas (10.71%). The 5- and 10-year overall survival rates of all NETs were 54.6% and 45.3%, respectively. Female and younger NETs patients had a better survival. The survival of all NETs diagnosed between 2010 and 2015 was better than those diagnosed between 2004 and 2009. Among the common sites of NETs, an improved survival of pancreatic NETs diagnosed between 2010 and 2015 compared to those diagnosed between 2004 and 2009 was observed. Overall, the incidence of NETs in Taiwan has continued to increase. The survival of pancreatic NET has shown a recent improvement. The development of novel therapeutic agents has the potential to improve the prognosis of NETs of other sites in the near future.
The global, randomized NAPOLI‐1 phase 3 trial reported a survival benefit with liposomal irinotecan (nal‐IRI) plus 5‐fluorouracil/leucovorin (nal‐IRI+5‐FU/LV) in patients with metastatic pancreatic ...ductal adenocarcinoma (mPDAC) after previous gemcitabine‐based therapy. Median overall survival (OS) with nal‐IRI+5‐FU/LV was 6.1 vs 4.2 months with 5‐FU/LV alone (unstratified hazard ratio HR = 0.67, P = .012). Herein, we report efficacy and safety results from a post‐hoc subgroup analysis of Asian patients treated at Asian centers. Primary study endpoint was OS; secondary endpoints included progression‐free survival (PFS), objective response rate (ORR), and safety. Patients receiving nal‐IRI+5‐FU/LV (n = 34) had significantly longer median OS versus 5‐FU/LV (n = 35) (8.9 vs 3.7 months; unstratified HR = 0.51, P = .025). Patients had significantly increased median PFS with nal‐IRI+5‐FU/LV versus 5‐FU/LV (4.0 vs 1.4; unstratified HR = 0.48, P = .011), and increased ORR (8.8% vs 0; P = .114). nal‐IRI monotherapy (n = 50) numerically improved efficacy endpoints versus 5‐FU/LV (n = 48): median OS was 5.8 versus 4.3 months (HR = 0.83, P = .423) and median PFS was 2.8 versus 1.4 months (HR = 0.69, P = .155). Grade ≥3 neutropenia was reported more frequently with nal‐IRI+5‐FU/LV versus 5‐FU/LV (54.5% vs 3.4%), and incidence of grade ≥3 diarrhea was comparable between the two arms (3.0% vs 6.9%). This subgroup analysis confirms nal‐IRI+5‐FU/LV as an efficacious treatment option that improves survival in Asian patients with mPDAC that progressed after gemcitabine‐based therapy, with a safety profile agreeing with previous findings. The nal‐IRI+5‐FU/LV regimen should represent a new standard of care for these patients in Asia. (Clinicaltrials.gov: NCT01494506)
The global NAPOLI‐1 phase 3 trial (NCT01494506) evaluated the safety and efficacy of liposomal irinotecan (nal‐IRI) and 5‐fluorouracil/leucovorin (5‐FU/LV) compared with 5‐FU/LV in patients with metastatic pancreatic adenocarcinoma that progressed following gemcitabine‐based therapy. We report data from a post‐hoc subgroup analysis focusing on Asian patients at centers in South Korea and Taiwan. Our findings are consistent with those from the primary analysis and show that, despite association with higher incidence of manageable grade 3‐4 neutropenia, the nal‐IRI+5‐FU/LV regimen is an effective treatment option in Asian patients with gemcitabine‐failed metastatic pancreatic cancer.
Background
Gastric cancer (GC) is the third leading cause of cancer mortality globally and a molecularly heterogeneous disease. Identifying the driver pathways in GC progression is crucial to ...improving the clinical outcome. Recent studies identified ASPM (abnormal spindle-like microcephaly-associated) and FOXM1 (Forkhead box protein M1) as novel Wnt and cancer stem cell (CSC) regulators; their pathogenetic roles and potential crosstalks in GC remain unclarified.
Methods
The expression patterns of ASPM isoforms and FOXM1 were profiled in normal gastric epithelial and GC tissues. The functional roles of ASPM and FOXM1 in Wnt activity, cancer stemness and GC progression, and the underlying signaling processes were investigated.
Results
Approximately one third of GC cells upregulate the expression of ASPM isoform I (ASPMiI) in their cytoplasm; the tumors with a high ASPMiI positive score (≥ 10%) are associated with a poor prognosis of the patients. Mechanistically, the molecular interplay among FOXM1, ASPMiI and DVL3 was found to converge on β-catenin to control the Wnt activity and the stemness property of GC cells. This multi-mode Wnt-regulatory module serves to reinforce Wnt signals in CSCs by transcriptional regulation (FOXM1–ASPM), protein–protein interactions (ASPMiI–DVL3–β-catenin), and nuclear translocation (FOXM1–β-catenin).
Conclusions
This study illuminates a novel Wnt- and stemness-regulatory mechanism in GC cells and identifies a novel subset of FOXM1
high
ASPMiI
high
GC with potential to guide Wnt- and stemness-related diagnostics and therapies.
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