High somatic mutations in circulating tumor DNA predict response of metastatic pancreatic ductal adenocarcinoma to first-line nab-paclitaxel plus S-1: prospective study.

AIMS: We previously showed that the nab-paclitaxel plus S-1 (NPS) regimen had promising effects against metastatic pancreatic ducal adenocarcinoma (mPDAC), whose efficacy however could not be precisely predicted by routine biomarkers. This prospective study aimed to investigate the values of mutations in circulating tumor DNA (ctDNA) and their dynamic changes in predicting response of mPDAC to NPS chemotherapy. METHODS: Paired tumor tissue and blood samples were prospectively collected from patients with mPDAC receiving first-line NPS chemotherapy, and underwent next-generation sequencing with genomic profiling of 425 genes for ctDNA. High mutation allelic frequency (MAF) was defined as ≥ 30% and ≥ 5% in tumor tissue and blood, respectively. Kappa statistics were used to assess agreement between mutant genes in tumor and ctDNA. Associations of mutations in ctDNA and their dynamic changes with tumor response, overall survival (OS), and progression-free survival (PFS) were assessed using the Kaplan-Meier method, multivariable-adjusted Cox proportional hazards regression, and longitudinal data analysis. RESULTS: 147 blood samples and 43 paired tumor specimens from 43 patients with mPDAC were sequenced. The most common driver genes with high MAF were KRAS (tumor, 35%; ctDNA, 37%) and TP53 (tumor, 37%; ctDNA, 33%). Mutation rates of KRAS and TP53 in ctDNA were significantly higher in patients with liver metastasis, with baseline CA19-9 ≥ 2000 U/mL, and/or without an early CA19-9 response. κ values for the 5 most commonly mutated genes between tumor and ctDNA ranged from 0.48 to 0.76. MAFs of the genes mostly decreased sequentially during subsequent measurements, which significantly correlated with objective response, with an increase indicating cancer progression. High mutations of KRAS and ARID1A in both tumor and ctDNA, and of TP53, CDKN2A, and SMAD4 in ctDNA but not in tumor were significantly associated with shorter survival. When predicting 6-month OS, AUCs for the 5 most commonly mutated genes in ctDNA ranged from 0.59 to 0.84, larger than for genes in tumor (0.56 to 0.71) and for clinicopathologic characteristics (0.51 to 0.68). Repeated measurements of mutations in ctDNA significantly differentiated survival and tumor response. Among the 31 patients with ≥ 2 ctDNA tests, longitudinal analysis of changes in gene MAF showed that ctDNA progression was 60 and 58 days ahead of radiologic and CA19-9 progression for 48% and 42% of the patients, respectively. CONCLUSIONS: High mutations of multiple driving genes in ctDNA and their dynamic changes could effectively predict response of mPDAC to NPS chemotherapy, with promising reliable predictive performance superior to routine clinicopathologic parameters. Inspiringly, longitudinal ctDNA tracking could predict disease progression about 2 months ahead of radiologic or CA19-9 evaluations, with the potential to precisely devise individualized therapeutic strategies for mPDAC.

PD-1 inhibitor combined with albumin paclitaxel and apatinib as second-line treatment for patients with metastatic gastric cancer: a single-center, single-arm, phase II study.

BACKGROUND: Immune checkpoint inhibitors have been approved for first- and third-line treatment of advanced gastric cancer. However, pembrolizumab alone in the second line did not improve overall survival compared to chemotherapy in the KEYNOTE-061 study. In this study, we aimed to explore the efficacy and safety of a three-drug regimen of PD-1 inhibitor combined with albumin paclitaxel and apatinib (a VEGFR inhibitor) for the second-line treatment of patients with metastatic gastric cancer (mGC). METHODS: This was a single-center, single-arm, phase II clinical study. Patients with mGC with stable microsatellite and negative HER-2 expression who failed first-line chemotherapy were enrolled. The enrolled patients were treated with PD-1 inhibitor (selected according to patients' requirements) in combination with albumin paclitaxel (125 mg/m2, intravenously, days 1 and 8, or 250 mg/m2, intravenously, day 1) and apatinib (250 or 500 mg, orally, days 1-21) every 3 weeks. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were overall survival (OS), objective response rate (ORR), disease control rate (DCR), duration of response, and adverse events (AEs). RESULTS: From July 11, 2019, to October 13, 2022, a total of 43 patients were enrolled, of whom 10 were PD-L1 negative, 11 were PD-L1 positive, and 22 had unknown PD-L1 expression. As of the data cutoff on April 1st, 2023, nine patients had partial response, 29 had stable disease, and five experienced progressive disease, with the ORR of 20.9% and DCR of 88.3%. The median PFS was 6.2 months (95% CI, 3.9-9.3), and the median OS was 10.1 months (95% CI, 7.5-14.1). All patients suffered from alopecia and neurotoxicity. The other main AEs of grade 1 or 2 were bone marrow suppression (N = 21, 48.8%), hand-foot reaction (N = 19, 44.2%), hypertension (N = 18, 41.9%), hypothyroidism (N = 11, 25.6%), gastrointestinal bleeding (N = 3, 7.0%), and liver function damage (N = 5, 11.6%). Two patients reported grade 3-4 immune-related liver damage. CONCLUSION: Second-line PD-1 inhibitor combined with albumin paclitaxel and apatinib showed certain efficacy and safety in patients with mGC. TRIAL REGISTRATION: Clinical trials, NCT04182724. Registered 27 November 2019; retrospectively registered, https://clinicaltrials.gov/study/NCT04182724.

Survival outcome of different treatment sequences in patients with locally advanced and metastatic pancreatic cancer.

BACKGROUND: Despite some therapeutic advances, improvement in survival rates of unresectable and/or metastatic pancreatic ductal adenocarcinoma (PDAC) has been minimal over recent decade. We aimed to evaluate the impact of different treatment sequences on clinical outcomes of advanced PDAC at our academic institution. METHODS: In this single institution retrospective analysis, we assessed characteristics and survival rates of unresectable and/or metastatic pancreatic PDAC patients who started a systemic treatment between 01/2015 and 12/2021. Survival analyses were performed by Kaplan-Meier and Cox proportional hazards model. RESULTS: The number of 285 patients received at least two lines of treatment, but only 137 patients were suitable for third-line treatment. Subgroup analysis showed that thirty-seven patients received A line (gemcitabine/nab-paclitaxel or nab-paclitaxel combined therapy to FOLFIRINOX) therapy, 37 patients received B line (nab-paclitaxel combined therapy to gemcitabine combined therapy to FOLFIRINOX) therapy, 21 patients received C line (nab-paclitaxel combined therapy to gemcitabine combined therapy to oxaliplatin or irinotecan combined therapy) therapy. Survival rates for different treatment lines were significantly different and median overall survival (OS) was 14.00, 18.00, and 14.00 months, respectively (p<0.05). CONCLUSION: Our study provides real-world evidence for the effectiveness of different treatment sequences and underscores the treatment sequences on survival outcome when considering the entire management in advanced PDAC.

A real-world analysis of second-line treatment option, gemcitabine plus anlotinib and anti-PD1, in advanced pancreatic cancer.

BACKGROUND: In the second-line treatment of advanced pancreatic cancer (APC), there is only one approved regimen based on the phase III NAPOLI-1 trial. However, for patients progressing after Nab-paclitaxel and Gemcitabine (Nab-P/Gem) or Nab-P combinations, second-line treatment were very limited. METHODS: This is a retrospective single-center analysis of patients. Our aim was to determine the effectiveness and tolerability of a novel regimen, gemcitabine plus Anlotinib and anti-PD1, in APC patients and to compare it with oxaliplatin, irinotecan, leucovorin, and fluorouracil (FOLFIRINOX) in the second-line setting who have failed on the first-line Nab-P combinations. RESULTS: In total, twenty-three patients received Gemcitabine plus Anlotinib and anti-PD1 in the second-line, 28 patients were treated with FOLFORINOX. There was no significant difference in overall survival (OS) or progression free survival (PFS) for either of the two sequences (p > 0.05). Patients who received Gemcitabine plus Anlotinib and anti-PD1 had a median PFS of 4.0 months (95% CI: 1.1-6.9) versus 3.5 months (95% CI 1.8-5.2) in FOLFORINOX group (p = 0.953). The median OS of Gemcitabine plus Anlotinib and anti-PD1 was 9.0 months (95% CI: 4.0-13.7) and 8.0 months (95% CI: 5.5-10.5) in FOLFORINOX group (p = 0.373). Grade ≥3 treatment-emergent adverse events (AEs) occurred for 13% of patients with Gemcitabine plus Anlotinib and anti-PD1 and 40% for FOLFORINOX. CONCLUSION: Our data confirms the effectiveness of Gemcitabine plus Anlotinib and anti-PD1 as a well-tolerated regimen in the second-line treatment of APC and extends available data on its use as a second-line treatment option when compared with FOLFIRINOX.

Topology and giant circular dichroism of enantiomorphic Kagome bands in a designed covalent organic framework.

Covalent organic frameworks (COFs) are an emerging class of crystalline organic materials that have shown potential to be a new physical platform. In this work, a designed COF named AB-COF, which has novel enantiomorphic Kagome bands, is proposed and a feasible route to synthesize it is given. Via a combination of first-principles calculations and tight-binding analysis, we investigate the electronic structures and the phase interference of the COF. It becomes topologically nontrivial when doping one iodine atom in a unit cell. The Berry curvatures of the valence band (VB) and conduction band (CB) of the iodine-doped AB-COF show opposite values and different distributions. This provides an opportunity to study the new mechanism of circular dichroism from the different Berry curvatures of the VB and CB. Surprisingly, the circular-dichroism dissymmetry factor of AB-COF reaches a theoretical maximum value, and the oscillator strength data are in agreement with this result. When two iodine atoms are doped in a unit cell, the Berry curvatures of the VB and CB also have different values, but with more symmetry and similar distributions. This behavior enhances the circular dichroism with a wider range of dissymmetric absorption, and the circular dichroism dissymmetry factor also reaches its theoretical maximum value.

Enantiomorphic kagome bands in a two-dimensional covalent organic framework with non-trivial magnetic and topological properties.

The kagome lattice is one of the most intriguing topics to study. It has a frustrated flat band touching a set of Dirac bands and can possess various promising properties, such as ferromagnetism, superconductivity, and a non-trivial topology. Covalent organic frameworks (COFs) are a rare type of inorganic material, however, they can provide a platform for generating certain required lattices. Based on first-principles density functional theory calculations, we show that a newly synthesized two-dimensional COF named COF-SH has novel enantiomorphic kagome bands, which include two sets of flat bands touching the Dirac bands around the Fermi level. The Bloch wave of the flat-valence band at the K-point shows the kagome nature of the phase interference. Under charge doping, the COF-SH exhibits a ferromagnetic ground state. Moreover, when COF-SH is doped with iodine atoms, a sizable gap in the system is opened between the flat bands and the Dirac bands due to the spin-orbit coupling (SOC) effect. Meanwhile, the spin degeneracy is lifted since the organic layer loses electrons due to the oxidizing property of iodine. In addition, our tight-binding analysis with the SOC effect shows that the flat valence band separates from the Dirac bands and holds a nonzero Chern number. Consequently, this I-doped COF can give rise to a quantum anomalous Hall effect.

Application of percutaneous biliary drainage in the treatment of post-operative bile leakage after liver rupture: A case report.

ABSTRACT: Post-operative bile leakage (POBL) is a serious complication following hepatobiliary surgery, with potentially life-threatening consequences if left untreated. This article presents a successful case of POBL management without surgical intervention. A 31-year-old male, diagnosed with bile leakage before hospitalisation, underwent percutaneous biliary drainage (PTBD) to address bilomas. Follow-up after 3 months indicated biloma atrophy and POBL healing but revealed bile duct stenosis. The patient received a larger biliary drainage tube, and after 1 month, the biloma and tube were removed. A 1-year follow-up confirmed the patient's excellent health. This case underscores the safety and efficacy of PTBD for managing POBL, offering a non-invasive alternative for patients with this complication. PTBD presents a viable treatment option for POBL cases, minimising the need for surgical interventions and their associated risks.

Enhanced photoelectric performance of MoSSe/MoS2 van der Waals heterostructures with tunable multiple band alignment.

Janus MoSSe with mirror asymmetry has recently emerged as a new two-dimensional (2D) material with a sizeable out-of-plane dipole moment. Here, based on first-principles calculations, we theoretically investigate the electronic properties of two patterns of 2D MoSSe/MoS2 van der Waals heterostructures (vdWHs). The electronic properties of MoSSe can be tuned by the intrinsic out-of-plane dipole field. When the Se side of the Janus layer faces the MoS2 layer, the dipole field points from the MoSSe layer towards the MoS2 layer, and the vdWH possesses a type-I band alignment which is desirable for light emission applications. With a reversal of the Janus layer, the intrinsic field inverts accordingly, and the band alignment becomes a typical type-II band alignment, which benefits carrier separation. Moreover, it possesses superior optical absorption (∼105 cm-1), and the calculated photocurrent density under visible-light radiation is up to 0.9 mA cm-2 in the MoSSe/MoS2 vdWH. Meanwhile, an external electric field and vertical strain can remarkably modulate the band alignment to switch it between type-I and type-II. Thus, MoSSe/MoS2 vdWHs have promising applications in next-generation photovoltaic devices.

Streptomyces populi sp. nov., a novel endophytic actinobacterium isolated from stem of Populus adenopoda Maxim.

A novel endophytic actinobacterium strain, designated A249T, was isolated from the stem of Populus adenopoda collected at Mount Qingcheng in south-west China. Its taxonomic position was determined by using a polyphasic approach. The cultural and morphological characteristics of isolate A249T were consistent with members of the genus Streptomyces. Growth occurred at 10-37 °C, pH 6.0-12.0 and in the presence of 0-4 % (w/v) NaCl. Analysis of the 16S rRNA gene sequence and phylogenetic trees showed the closest phylogenetic relatives to strain A249T were Streptomyces shaanxiensis JCM 16925T (98.0 % 16S rRNA gene sequence similarity) and Streptomyces lanatus JCM 4332T (97.9 %). The DNA-DNA hybridization values between the strain A249T and the two reference strains ranged from 41.4 to 49.4 %. The DNA G+C content was 71.7 mol%. The range of average nucleotide identity values was 81.5-86.7 %. Chemical analysis of cellular components indicated that strain A249T contained ll-diaminopimelic acid, xylose and galactose. The predominant menaquinones were MK-9(H6) and MK-9(H8). The polar lipids were diphosphatidylglycerol, phosphatidylinositol mannosides, phosphatidylethanolamine, two unidentified lipids, one unidentified phospholipid, one unidentified aminolipid and one unidentified aminophospholipid. The major fatty acids comprised C16 : 0, iso-C14 : 0, iso-C15 : 0, iso-C16 : 0, anteiso-C15 : 0 and C16 : 1ω7c. On the basis of the phenotypic and genotypic differentiation of the three tested strains, isolate A249T is proposed to represent a novel species of the genus Streptomyces, named Streptomyces populi sp. nov. The type strain is A249T (=CGMCC 4.7417T=JCM 32175T).

Actinocorallia populi sp. nov., an endophytic actinomycete isolated from a root of Populus adenopoda (Maxim.).

An endophytic actinobacterium, strain A251T, was isolated from the root of Populus adenopoda Maxim and subjected to characterization using polyphasic taxonomy. Analysis of the 16S rRNA gene sequence revealed that the isolate represented a member of the phylogenetic cluster of the genus Actinocorallia and was most closely related to Actinocorallia aurantiaca JCM 8201T (98.0 %) and Actinocorallia libanotica IFO 10495T (98.0 %). DNA-DNA hybridization values between A251T and these strains were 41.2 % and 45.0 %, respectively. The G+C content of the DNA was 71.5 mol%. Major fatty acids were C16 : 0, C16 : 1ω7c and C18 : 1ω9c. The peptidoglycan diamino acid of A251T was meso-diaminopimelic acid and the whole-cell hydrolysates contained glucose and ribose. The major menaquinones were MK-9(H4) and MK-9(H6). The phospholipid profile included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, an undefined aminophospholipid and two undefined phospholipids. DNA-DNA hybridization data in combination with differences in the biochemical and physiological properties, indicated that A251T should be classified as representing a novel species within the genus Actinocorallia, for which the name Actinocorallia populi sp. nov. is proposed, with A251T (=CGMCC 4.7421T=JCM 32178T) as the type strain.

Planococcus halotolerans sp. nov., isolated from a saline soil sample in China.

A novel Gram-stain-positive, coccoid or short rod-shaped, moderate-orange-pigmented, halotolerant and psychrotolerant bacterium, designated strain SCU63T, was isolated from a saline soil sample in China, and characterized by a polyphasic taxonomic approach. 16S rRNA gene sequence similarity of strain SCU63T to species in the genera Planococcus and Planomicrobium ranged from 96.5 to 98.6 %. Phylogenetic trees as well as diagnostic signature nucleotides in the 16S rRNA gene sequence supported the view that this strain should be assigned to the genus Planococcus. Further, average nucleotide identity and digital DNA-DNA hybridization analyses confirmed the separate species status of strain SCU63T relative to the closely related taxa. The isolate grew at 0-40 °C (optimum, 30-35 °C), at pH 6.5-9.0 (pH 7.0-7.5) and in the presence of 0-15 % (w/v) NaCl (3 %). The principal fatty acids were anteiso-C15 : 0, C16 : 1ω7c alcohol, iso-C16 : 0 and iso-C14 : 0, and the dominant isoprenoid quinones were MK-8 and MK-7. The peptidoglycan type was determined to be A4α (l-Lys-d-Glu), and the polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminophospholipid and one unidentified lipid. The DNA G+C content was 44.6 mol%. Based on the genotypic, phenotypic and chemotaxonomic data, strain SCU63T can be classified as a novel species in the genus Planococcus, for which the name Planococcushalotolerans sp. nov. is proposed. The type strain is SCU63T (=CGMCC 1.13628T=KCTC 43001T).

Ornithinibacillus salinisoli sp. nov., a moderately halophilic bacterium isolated from a saline-alkali soil.

A taxonomic study was performed on strain LCB256T, which was isolated from a saline-alkali soil sample taken from northwestern China. Cells of strain LCB256T were Gram-stain-positive, aerobic, rod-shaped and grew at 3-17 % (w/v) NaCl (optimum 10-15 %), 10-52 °C (optimum 25-30 °C) and pH 7.0-9.0 (optimum 8.0). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain LCB256T was most closely related to the two genera of Ornithinibacillus and Oceanobacillus, showing highest sequence similarity to Oceanobacillus limi KCTC 13823T (97.8 %) and Ornithinibacillus bavariensis WSBC 24001T (97.2 %). The peptidoglycan amino acid type was found to be A4ß and the major respiratory quinone was determined to be MK-7. The polar lipid profile of strain LCB256T contained diphosphatidylglycerol, phosphatidylglycerol, one unidentified phospholipid and two unidentified aminolipids. The dominant cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The G+C content of genomic DNA was 39.3 mol%. DNA-DNA relatedness values between strain LCB256T and Ornithinibacillus halophilus KCTC 13822T and Oceanobacillus limi KCTC 13823T were 46.2 and 34.8 %, respectively. Based on this polyphasic taxonomic study, a novel species of the genus Ornithinibacillus, Ornithinibacillussalinisoli sp. nov. is proposed. The type strain is LCB256T (=CGMCC 1.15809T=KCTC 33862T).

Streptomyces dioscori sp. nov., a Novel Endophytic Actinobacterium Isolated from Bulbil of Dioscorea bulbifera L.

A novel endophytic actinobacterium strain, A217T, was isolated from the bulbil of Dioscorea bulbifera L. Its taxonomic position was characterized using a polyphasic study. Morphological and chemotaxonomic characteristics of strain A217T were consistent with those of members of the genus Streptomyces: long straight to flexuous spore chain; cellular components contained LL-diaminopimelic acid, ribose, and small traces of glucose in whole-cell hydrolysates; MK-9(H6) and MK-9(H8) as predominant menaquinones. The patterns of major fatty acids are C16:0, anteiso-C15:0, C15:0, iso-C14:0, C16:1 ω7c, anteiso-C17:0, and iso-C17:1 ω5c. The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol mannoside, and glycolipid, as well as two unidentified phospholipids, one unidentified aminolipid, and one unidentified aminophospholipid. The DNA G + C content of draft genome is 70.7 mol%. Analysis of the 16S rRNA gene sequence and phylogenetic trees revealed that the isolate was most closely related to S. aurantiacus JCM 4453T (99.0%), S. glomeroaurantiacus JCM 4677T (99.0%), and S. tauricus JCM 4837T (98.8%). The DNA-DNA hybridization values between the strain A217T and three reference strains ranged from 34.6% to 51.7%. On the basis of phenotypic and genotypic differentiation from all tested strains, isolate A217T is proposed to represent a novel species of the genus Streptomyces, named Streptomyces dioscori sp. nov. The type strain is A217T (= CGMCC 4.7415T = JCM 32173T).

[Prognostic Factors of Stage 3 Colorectal Cancer in 433 Patients].

OBJECTIVE: To summarize the prognostic factors of stage 3 colorectal cancer. METHODS: The clinical data of 433 patients with stage 3 colorectal cancer who were admitted to our hospital from January 2005 to December 2008 for radical surgery and adjuvant chemotherapy were retrospectively analyzed. Relationship of their clinicopathologic features and treatment with the prognosis were analyzed. RESULTS: Of these 433 stage 3 patients,the mean disease-free survival was (72.37 ± 2.11) months and mean overall survival was (79.91 ± 2.02) months; however, the median survival times were not reached. The 1-,3-, and 5-year disease-free survival rate were 86.8%,77.9%, and 57.0% and the overall survival rate were 91.5%,75.1%, and 63.3%. Multivariate COX regression analysis displayed that intestine obstruction before surgery, complications after surgery,tumor location,positive surgical margin, neural cell infiltration,vessel cancer embolus, TNM stage, lymph node ratio, adjuvant chemotherapy regimens, and chemotherapy duration were the independent factors affecting disease-free and overall survivals in patients with stage 3 colorectal cancer. The efficacies of FOLFOX and XELOX regimens were significantly correlated with patient's age, complications,tumor location,and chemotherapy duration. CONCLUSIONS: Complications,tumor location, TNM stage, and positive surgical margin are the independent prognostic factors of stage 3 colorectal cancer. FOLFOX and XELOX regimen can remarkably improve prognosis,and a longer duration of chemotherapy can achieve better survival.

Microbial metabolism of diosgenin by a novel isolated Mycolicibacterium sp. HK-90: A promising biosynthetic platform to produce 19-carbon and 21-carbon steroids.

Green manufacture of steroid precursors from diosgenin by microbial replacing multistep chemical synthesis has been elusive. It is currently limited by the lack of strain and degradation mechanisms. Here, we demonstrated the feasibility of this process using a novel strain Mycolicibacterium sp. HK-90 with efficiency in diosgenin degradation. Diosgenin degradation by strain HK-90 involves the selective removal of 5,6-spiroketal structure, followed by the oxygenolytic cleavage of steroid nuclei. Bioinformatic analyses revealed the presence of two complete steroid catabolic gene clusters, SCG-1 and SCG-2, in the genome of strain HK-90. SCG-1 cluster was found to be involved in classic phytosterols or cholesterol catabolic pathway through the deletion of key kstD1 gene, which promoted the mutant m-∆kstD1 converting phytosterols to intermediate 9α-hydroxyandrostenedione (9-OHAD). Most impressively, global transcriptomics and characterization of key genes suggested SCG-2 as a potential gene cluster encoding diosgenin degradation. The gene inactivation of kstD2 in SCG-2 resulted in the conversion of diosgenin to 9-OHAD and 9,16-dihydroxy-pregn-4-ene-3,20-dione (9,16-(OH)2 -PG) in mutant m-ΔkstD2. Moreover, the engineered strain mHust-ΔkstD1,2,3 with a triple deletion of kstDs was constructed, which can stably accumulate 9-OHAD by metabolizing phytosterols, and accumulate 9-OHAD and 9,16-(OH)2 -PG from diosgenin. Diosgenin catabolism in strain mHust-ΔkstD1,2,3 was revealed as a progression through diosgenone, 9,16-(OH)2 -PG, and 9-OHAD to 9α-hydroxytestosterone (9-OHTS). So far, this work is the first report on genetically engineered strain metabolizing diosgenin to produce 21-carbon and 19-carbon steroids. This study presents a promising biosynthetic platform for the green production of steroid precursors, and provide insights into the complex biochemical mechanism of diosgenin catabolism.

PD-1 inhibitors-based second-line therapy for metastatic gastric cancer.

Background: Metastatic gastric cancer (MGC) patients with progression on first-line treatment still have poor outcomes on chemotherapy. The KEYNOTE-061 study demonstrated that pembrolizumab, a PD-1inhibitor, was not better than paclitaxel as second-line therapy for MGC. Herein, we explored the efficacy and safety of PD-1inhibitor based treatment for MGC patients in the second line. Methods: In this observational, retrospective study, we enrolled MGC patients treated with anti-PD-1 based therapy as second-line in our hospital. We primarily assessed the treatment's efficacy and safety. We also evaluated the relationship between clinical features and outcomes using univariate and multivariate analyses. Results: We enrolled 129 patients with an objective response rate (ORR) of 16.3% and a disease control rate (DCR) of 79.1%. Patients treated with PD-1inhibitor combined with chemotherapy and anti-angiogenic agents had ORR of 19.6% and higher DCR of 94.1%. The median progression-free survival (PFS) was 4.10 months, and the median overall survival (OS) was 7.60 months. In univariate analysis, patients treated with PD-1inhibitor combined with chemotherapy and anti-angiogenic agents and with prior anti-PD-1 history were significantly associated with favorable PFS and OS. In the multivariate analysis, different combination therapy and prior anti-PD-1 history were independent prognosis biomarkers for PFS and OS. Grade 3 or 4 treatment-related adverse events (TRAEs) occurred in 28 (21.7%) patients. Common adverse events (AEs) included fatigue, hyper/hypothyroidism, neutrophil decrease, anemia, skin reactions, proteinuria, and hypertension. We did not observe treatment-related deaths. Conclusion: Our current results indicated that PD-1-inhibitor and chemo-anti-angiogenic agents combination therapy and prior PD-1 treatment history might improve clinical activity for GC immunotherapy as second-line treatment with acceptable safety profiles. Further studies are needed to verify those outcomes for MGC in other centers.

Prognostic value of the Lung Immune Prognostic Index for HER-2-negative metastatic gastric cancer.

Background: The aim of this study was to explore whether the Lung Immune Prognostic Index (LIPI) is associated with clinical outcomes in patients with metastatic gastric cancer (MGC) treated with anti-PD-1 and chemotherapy. Methods: Patients with MGC treated with an anti-PD-1 therapy or chemotherapy were enrolled. This study was composed of two cohorts including 266 patients in the anti-PD-1-treated group and 139 patients in the chemotherapy-treated group. Results: Patients treated with anti-PD-1 therapy that also showed a good LIPI showed a longer median progression-free survival and median overall survival in patients with an intermediate or poor LIPI. These outcomes were not observed in the chemotherapy cohort. Conclusion: Good LIPI correlated with better outcomes for patients with MGC in the anti-PD-1-treated group but not in the chemotherapy-treated group.

The influence of dust on extreme precipitation at a large city in North China.

In recent decades, the Beijing-Tianjin-Hebei city cluster is experiencing rapid urbanization along with economic booming. Meanwhile, these cities are suffering the influence of extreme precipitation and dust storms. In this study, the impact of dust aerosol on extreme precipitation that occurred in Beijing during 19-21 July 2016 is investigated using both satellite retrievals and Weather Research and Forecasting model coupled to Chemistry (WRF-Chem) model simulations. Results reveal that the dust particles can increase extreme precipitation by promoting the formation of ice clouds and enhancing convections. The dust is lifted into the upper troposphere (>10 km) via strong convection and affects the physical process of precipitation after long-range transport. It further transforms the supercooled water into the middle and high levels of ice nuclei (IN). These promote the formation of ice clouds according to the decreased effective radius of IN and increased ice water path, respectively. Along with sufficient water vapor transport and strong convergence, the formation of IN could release more latent heat and further strengthen convection development. Thus, the precipitation amount in southern Beijing is almost enhanced by 40 % (>80 mm). This study will provide a deep insight into understanding the causes of urban extreme precipitation.

Functional identification and prediction of lncRNAs in esophageal cancer.

Esophageal cancer is a highly lethal malignancy with poor prognosis, and the identification of molecular biomarkers is crucial for improving diagnosis and treatment. Long non-coding RNAs (lncRNAs) have been shown to play important roles in the development and progression of esophageal cancer. However, due to the time cost of biological experiments, only a small number of lncRNAs related to esophageal cancer have been discovered. Currently, computational methods have emerged as powerful tools for identifying and characterizing lncRNAs, as well as predicting their potential functions. Therefore, this article proposes a transformer-based method for identifying esophageal cancer-related lncRNAs. Experimental results show that the AUC and AUPR of this method are superior to other comparison methods, with an AUC of 0.87 and an AUPR of 0.83, and the identified lncRNA targets are closely associated with esophageal cancer. We focus on the role of esophageal cancer-related lncRNAs in the immune microenvironment, and fully explore the functions of the target genes regulated by lncRNAs. Enrichment analysis shows that the predicted target genes are related to multiple pathways involved in the occurrence, development, and prognosis of esophageal cancer. This not only demonstrates the effectiveness of the method but also indicates the accuracy of the prediction results.

Regulatory T cells increase in breast cancer and in stage IV breast cancer.

Expression levels of VEGF and Her-2, levels of T-regulatory (Treg) cells, levels of CD3+ cells, and ratios of Th (CD4+ T cells)/Tr (Treg) cells were compared between stage I, II, III, and IV breast cancer patients (n = 120) prior to chemotherapy and healthy women (n = 30). Cells from peripheral blood were counted by flow cytometry, Her-2 and VEGF expression was detected by pathological examination, and Her-2 was detected by FISH. Breast cancer patients had more Treg cells and a lower ratio of Th/Tr cells than the healthy women. Stage IV breast cancer patients had more Treg cells and a lower ratio of Th/Tr cells than stage I, II, or III breast cancer patients. Patients positive for VEGF had a lower ratio of Th/Tr cells compared with patients negative for VEGF, and those positive for both VEGF and Her-2 also had a lower ratio of Th/Tr cells compared with patients not positive for both VEGF and Her-2. The decreased Th/Tr cells ratio indicates impaired immune function, suggesting that the stage IV breast cancer and the Her-2/VEGF-positive breast cancer patients have lower immune function.