Molecular insight into algae-derived dissolved organic matters via Fourier-transform ion cyclotron resonance mass spectrometry: Effects of pretreatment methods and electrospray ionization modes.

The release of algae-derived dissolved organic matter (ADOM) significantly increased in serious eutrophication waters, posing great threats to drinking water safety. Thus, the molecular composition decipherment is urgently in need. However, due to unsatisfactory pretreatment and ionization effects, the application of Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) on ADOM was limited. Therefore, the effects of pretreatment methods (cartridge type and loading) during solid-phase extraction (SPE) and electrospray ionization (ESI) modes with FT-ICR-MS on the molecular composition of ADOM were evaluated. The results showed compared with silica-based octadecyl (C18) cartridge, styrene-divinylbenzene polymer (PPL) cartridge exhibited higher recovery efficiency and retained more saturated and oxygenated compounds, such as carbohydrate-like and tannin-like. Furthermore, the recovery efficiency decreased with increasing loading, and hydrophilic and high-oxygenated carbohydrate-like and tannin-like were continuously replaced by hydrophobic and low-oxygenated aliphatic and aromatic compounds. Moreover, compared to negative ESI mode, the addition of positive ESI mode increased the molecular chemodiversity, especially more lipid-like and protein-like compounds. Thus, we proposed < 1:500 DOC/PPL mass ratio during SPE and dual ESI modes coupled with FT-ICR-MS could identify ADOM molecules more comprehensively. This work contributes to more comprehensive understanding of the molecular composition of ADOM and provides more references for pretreatment and characterization strategies of severely eutrophic waters.

Multi-step HPLC fractionation enabled in-depth and unbiased characterization of histone PTMs.

Histone post-translational modifications (PTMs) are critical epigenetic regulatory factors. Histone PTMs are highly dynamic and complicated, encompassing over 30 structurally diverse modifications across nearly 180 amino acid residues, which generated extensive information regarding histone marks. In proteomics-based characterization of histone PTMs, chemical derivatization and antibody-based affinity enrichment were frequently utilized to improve the identification depth. However, chemical derivatization suffered from the occurrence of side reactions, and antibody-based affinity enrichment focused on specific PTM types of interest. In this research, we developed a multi-step fractionation strategy for comprehensively unbiased detection of histone PTM sites. By combining protein-level fractionation with peptide-level alkaline and acid phase fractionation, we developed the Multidimensional Fractionation based Histone Mark Identification Technology (MudFIT) and increased PTM identification to a total of 264 histone PTM sites. To the best of our knowledge, this strategy achieved the most comprehensive characterization of histone PTM sites in a single proteomics study. Using the same starting amount of sample, MudFIT identified more Kac sites and Kac peptides than those in antibody-based acetylated peptide enrichment. Moreover, in addition to well-studied histone marks, we discovered 36 potential new histone PTM sites including H2BK116bu, H4R45me2, H1K63pr, and uncovered unknown histone PTM types like aminoadipic on lysine and nitrosylation on tyrosine. Our data provided a method and resource for in-depth characterization of histone PTM sites, facilitating further biological understanding of histone marks.

Understanding the Role of Low-Dose Polystyrene Microplastic in Copper Toxicity to Rice Seed (Oryza sativa L.).

There is still much to learn with respect to the potential for microplastics (MPs) to interact with environmental toxins and biota. In the present study, we investigated the effect of MPs on the toxicity of copper (Cu) to rice seeds (Oryza sativa L.). The 7-day median effective concentration (EC50) value of MPs on rice seed germination was 864 mg/L (95% confidence interval [CI] 839 to 897 mg/L). We found that MPs slightly reduced Cu toxicity to rice seeds. The 7-day EC50 of Cu on rice seed germination increased from 7.29 mg/L (95% CI 7.10-7.52 mg/L) to 7.93 mg/L (95% CI 7.58-8.08 mg/L) in the presence of 20 mg/L MPs. We examined this toxicity reduction phenomenon by investigating the role of MPs in the process of Cu transport, Cu accumulation, and metabolic responses. Further investigation found that the MPs used in the present study hardly adsorbed Cu, but these MPs accumulated on the coats of rice seeds and significantly reduced Cu accumulation in rice seedlings. When Cu concentration was 10 mg/L, the presence of MPs reduced the accumulation of Cu in rice seedlings by 34%. We also found that, compared with only Cu present, the addition of MPs resulted in lower reactive oxygen species accumulation and higher catalase activity and glutathione levels in rice seedlings, which also contributed to Cu toxicity reduction. Collectively, the present study shows that polystyrene MPs have the potential to form associations with plant structures which can ultimately impact heavy metal bioaccessibility and therefore toxicity. Environ Toxicol Chem 2024;43:1870-1879. © 2024 SETAC.

Proteomics analysis of histone deacetylase inhibitor-resistant solid tumors reveals resistant signatures and potential drug combinations.

Histone deacetylase inhibitors (HDACis) are important drugs for cancer therapy, but the indistinct resistant mechanisms of solid tumor therapy greatly limit their clinical application. In this study we conducted HDACi-perturbated proteomics and phosphoproteomics analyses in HDACi-sensitive and -resistant cell lines using a tandem mass tag (TMT)-based quantitative proteomic strategy. We found that the ribosome biogenesis proteins MRTO4, PES1, WDR74 and NOP16 vital to tumorigenesis might regulate the tumor sensitivity to HDACi. By integrating HDACi-perturbated protein signature with previously reported proteomics and drug sensitivity data, we predicted and validated a series of drug combination pairs potentially to enhance the sensitivity of HDACi in diverse solid tumor. Functional phosphoproteomic analysis further identified the kinase PDK1 and ROCK as potential HDACi-resistant signatures. Overall, this study reveals the potential HDACi-resistant signatures and may provide promising drug combination strategies to attenuate the resistance of solid tumor to HDACi.

A Comparison of Clinicopathologic Outcomes and Patterns of Lymphatic Spread Across Neoadjuvant Chemotherapy, Neoadjuvant Chemoradiotherapy, and Neoadjuvant Immunochemotherapy in Locally Advanced Esophageal Squamous Cell Carcinoma.

BACKGROUND: Neoadjuvant chemoradiotherapy (NCRT) is recommended as the treatment standard for locally advanced esophageal squamous cell carcinoma (ESCC). The use of immunotherapy in the neoadjuvant setting has gained attention. Multiple, clinical trials have explored the efficacy and safety of neoadjuvant immunochemotherapy (NICT). We evaluated the differences in clinicopathologic outcomes and the patterns of lymphatic spread among patients receiving neoadjuvant chemotherapy (NCT), NCRT, and NICT before esophagectomy for locally advanced ESCC. METHODS: A total of 702 patients with ESCC who completed transthoracic esophagectomy followed neoadjuvant therapy were included. Pathological characteristics, including pathologic complete response (pCR), tumor regression grade (TRG) score and patterns of lymphatic spread, were evaluated. RESULTS: Compared with the NCT group, the NCRT group and NICT group had an advantage in pathological response (P < 0.05). The pCR rate was 8.1% in the NCT group, 29.9% in the NCRT group, and 23.6% in the NICT group. The TRG score (P < 0.05) and pathologic T stage (P < 0.05) in the NCT group were significantly higher. Compared with NICT, NCRT can significantly reduce the rate of lymph node metastasis rate in station 1R (0 vs. 3.4%, P < 0.05) and 2R (1.1% vs. 6.8%, P < 0.05). Subgroup analysis according to the tumor location distribution showed that NICT group had higher lymph node metastasis rate in station 2R (9.1%) in middle thoracic cases (P < 0.05) and in station 18 (7.5%) (P < 0.05) in lower thoracic cases. CONCLUSIONS: NCRT or NICT followed by surgery may result in a promising pCR rate and show a better performance in therapeutic response of primary lesion. For patients with lymph node metastasis in station 1R and 2R, NCRT should be the optimal preoperative treatment strategy.

Iron minerals: A frontline barrier against combined toxicity of microplastics and arsenic.

The coexistence of microplastics (MPs) and arsenic (As) in terrestrial ecosystems presents challenges to controlling soil pollution and performing environmental risk assessments. In this study, the interactions among As, polystyrene MPs, and goethite in porous media were investigated and the individual and combined toxicities of MPs and As on wheat germination were evaluated. An additional experiment was conducted to assess the mitigating effect of goethite on the toxicity of the two contaminants. The results showed that the presence of MPs reduced As accumulation in wheat and decreased the acute lethal toxicity of As pollutants (the half-lethal concentration of As during wheat germination increased by 68.21%). However, MPs exhibited inhibitory effects on wheat germination and served as carriers to promote the migration of As within the plant body. The addition of goethite mitigated both individual and combined toxicities and further increased the half-lethal concentration for the combined pollution of As and MPs by 39.48%. This was primarily attributed to the adsorption and immobilization of arsenate and MPs on the medium and root surfaces. In our study, goethite reduced soluble As by 48.29% under the combined pollution scenarios and formed iron plaques on wheat roots, effectively obstructing pollutant entry. Thus, iron minerals serve as pioneering barriers to combined toxicity. Our findings contribute to the understanding of the combined toxicity of MPs and As in crops and offer potential strategies for managing combined pollution.

Fecal microbiota transplantation plus tislelizumab and fruquintinib in refractory microsatellite stable metastatic colorectal cancer: an open-label, single-arm, phase II trial (RENMIN-215).

Background: Immunotherapy has revolutionized the treatment of cancer. However, microsatellite stable (MSS) metastatic colorectal cancer (mCRC) shows a low response to PD-1 inhibitors. Antiangiogenic therapy can enhance anti-PD-1 efficacy, but it still cannot meet clinical needs. Increasing evidence supported a close relationship between gut microbiome and anti-PD-1 efficacy. This study aimed to explore the efficacy and safety of the combination of fecal microbiota transplantation (FMT) and tislelizumab and fruquintinib in refractory MSS mCRC. Methods: In the phase II trial, MSS mCRC patients were administered FMT plus tislelizumab and fruquintinib as a third-line or above treatment. The primary endpoint was progression-free survival (PFS). Secondary endpoints were overall survival (OS), objective response rate (ORR), disease control rate (DCR), duration of response (DoR), clinical benefit rate (CBR), safety and quality of life. Feces and peripheral blood were collected for exploratory biomarker analysis. This study is registered with Chictr.org.cn, identifier ChiCTR2100046768. Findings: From May 10, 2021 to January 17, 2022, 20 patients were enrolled. Median follow-up was 13.7 months. Median PFS was 9.6 months (95% CI 4.1-15.1). Median OS was 13.7 months (95% CI 9.3-17.7). Median DoR was 8.1 months (95% CI 1.7-10.6). ORR was 20% (95% CI 5.7-43.7). DCR was 95% (95% CI 75.1-99.9). CBR was 60% (95% CI 36.1-80.9). Nineteen patients (95%) experienced at least one treatment-related adverse event (TRAE). Six patients (30%) had grade 3-4 TRAEs, with the most common being albuminuria (10%), urine occult blood (10%), fecal occult blood (10%), hypertension (5%), hyperglycemia (5%), liver dysfunction (5%), hand-foot skin reaction (5%), and hypothyroidism (5%). No treatment-related deaths occurred. Responders had a high-abundance of Proteobacteria and Lachnospiraceae family and a low-abundance of Actinobacteriota and Bifidobacterium. The treatment did not change the structure of peripheral blood TCR repertoire. However, the expanded TCRs exhibited the characteristics of antigen-driven responses in responders. Interpretation: FMT plus tislelizumab and fruquintinib as third-line or above treatment showed improved survival and manageable safety in refractory MSS mCRC, suggesting a valuable new treatment option for this patient population. Funding: This study was supported by the National Natural Science Foundation of China (82102954 to Wensi Zhao) and the Special Project of Central Government for Local Science and Technology Development of Hubei Province (ZYYD2020000169 to Yongshun Chen).

Durable responses to TAS-102 plus bevacizumab and TACE in salvage-line treatment of KRAS-mutated and MSS metastatic colorectal cancer: a case report.

Patients with KRAS-mutated and microsatellite-stable (MSS) metastatic colorectal cancer (mCRC) often have limited options in salvage-line treatment. Reasonable combination strategy may be a valuable exploration. Here, we report a patient with KRAS-mutated and MSS metastatic rectal adenocarcinoma at stage IVB. After failure of previous standard treatment, a durable stable disease was achieved under the fifth-line treatment of TAS-102 plus bevacizumab and transcatheter arterial chemoembolization (TACE). To date, the patient had a PFS of more than 11.6 months with significantly declined tumor markers, alleviated clinical symptoms and improved quality of life. This case suggests that TAS-102 combined with re-challenged bevacizumab and well-timed TACE intervention is an effective strategy for KRAS-mutated and MSS mCRC, with good tolerance and manageable safety, even following disease progression on prior fruquintinib and regorafenib therapies.

Efficacy of endoscopic therapy for T1b esophageal cancer and construction of prognosis prediction model: a retrospective cohort study.

BACKGROUND: The efficacy of endoscopic therapy on the long-term survival outcomes of T1b oesophageal cancer (EC) is unclear, this study was designed to clarify the survival outcomes of endoscopic therapy and to construct a model for predicting the prognosis in T1b EC patients. METHODS: This study was performed using the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2017 of patients with T1bN0M0 EC. Cancer-specific survival (CSS) and overall survival (OS) were compared between endoscopic therapy group, esophagectomy group and chemoradiotherapy group, respectively. Stabilized inverse probability treatment weighting was used as the main analysis method. The propensity score matching method and an independent dataset from our hospital were used as sensitivity analysis. The least absolute shrinkage and selection operator regression (Lasso) was employed to sift variables. A prognostic model was then established and was verified in two external validation cohorts. RESULTS: The unadjusted 5-year CSS was 69.5% (95% CI, 61.5-77.5) for endoscopic therapy, 75.0% (95% CI, 71.5-78.5) for esophagectomy and 42.4% (95% CI, 31.0-53.8) for chemoradiotherapy. After stabilized inverse probability treatment weighting adjustment, CSS and OS were similar in endoscopic therapy and esophagectomy groups ( P =0.32, P =0.83), while the CSS and OS of chemoradiotherapy patients were inferior to endoscopic therapy patients ( P <0.01, P <0.01). Age, histology, grade, tumour size, and treatment were selected to build the prediction model. The area under the curve of receiver operating characteristics of 1, 3, and 5 years in the validation cohort 1 were 0.631, 0.618, 0.638, and 0.733, 0.683, 0.768 in the validation cohort 2. The calibration plots also demonstrated the consistency of predicted and actual values in the two external validation cohorts. CONCLUSION: Endoscopic therapy achieved comparable long-term survival outcomes to esophagectomy for T1b EC patients. The prediction model developed performed well in calculating the OS of patients with T1b EC.

Durable responses to tislelizumab plus fruquintinib and radiotherapy in refractory microsatellite stable metastatic colorectal cancer: a case report.

Immunotherapy has changed the landscape of contemporary cancer treatment. Different from microsatellite instability-high colorectal cancer (CRC), the microsatellite-stable (MSS) CRC shows little response to immunomonotherapy. Reasonable drug combinations may be a valuable exploration to solve this the dilemma. Here, we report a young patient with refractory metastatic rectal adenocarcinoma at stage IVb who achieved a durable partial response after receiving tislelizumab plus fruquintinib and well-timed local radiotherapy. To date, the patient has a progression-free survival of more than 12 months with obviously declined serum tumor markers, increased peripheral blood effector T cells, alleviated scrotal edema and improved quality of life. This case suggests that an immune checkpoint inhibitor combined with an anti-VEGFR-tyrosine kinase inhibitor and local radiation intervention might be an effective strategy for heavily pretreated metastatic CRC patients with MSS phenotype.

Radiotherapy plus camrelizumab and irinotecan for oligometastatic esophageal squamous cell carcinoma patients after first-line immunotherapy plus chemotherapy failure: An open-label, single-arm, phase II trial.

BACKGROUND AND PURPOSE: Immunotherapy has revolutionized the treatment of advanced and metastatic esophageal squamous cell carcinoma (ESCC), but most patients eventually developed disease progression. Immuno-resistance is becoming an unavoidable clinical problem. Oligometastasis is a limited-metastatic state, and patients at this stage should be evaluated for the addition of metastasis-directed local intervention, which may be associated with improved prognosis. As an immunomodulator, radiotherapy may exhibit synergistic effect when added to immunotherapy. This study assessed the efficacy and safety of low-dose radiotherapy plus immunotherapy and second-line chemotherapy in oligometastatic ESCC. MATERIALS AND METHODS: In this phase II trial (ChiCTR2000040533), oligometastatic ESCC patients after first-line immunotherapy plus chemotherapy failure were treated with low dose radiotherapy plus camrelizumab and second-line irinotecan chemotherapy. The primary endpoint was progression-free survival (PFS). Secondary endpoints were overall survival (OS), objective response rate (ORR), disease control rate (DCR), clinical benefit rate (CBR), and safety. Abscopal response rate (ARR) and abscopal control rate (ACR) were also been explored. RESULTS: Between November 19, 2018 and March 17, 2021, 49 patients were enrolled. With a median follow-up of 12.8 months, median PFS and OS were 6.9 months (95%CI, 4.6-9.3) and 12.8 months (95%CI, 10.1-15.5), respectively. ORR was 40.8% (95%CI, 27.3-55.7). DCR was 75.5% (95%CI, 60.8-86.2). ARR was 34.7% (95%CI, 22.1-49.7). ACR was 69.4% (95%CI, 54.4-81.3). The most common adverse effects of any grade were myelosuppression, weight loss and fatigue. Grade 3 or 4 treatment-related adverse events occurred in 31 (63.3%) patients, with the most common being leukopenia (30.6%). No treatment-related deaths occurred. CONCLUSION: Low dose radiotherapy plus camrelizumab and irinotecan exhibited survival benefit with manageable safety for oligometastatic ESCC patients after first-line immunotherapy plus chemotherapy failure. It deserves to be validated in a larger trial.

Integrative multi-omics and drug-response characterization of patient-derived prostate cancer primary cells.

Prostate cancer (PCa) is the second most prevalent malignancy in males across the world. A greater knowledge of the relationship between protein abundance and drug responses would benefit precision treatment for PCa. Herein, we establish 35 Chinese PCa primary cell models to capture specific characteristics among PCa patients, including gene mutations, mRNA/protein/surface protein distributions, and pharmaceutical responses. The multi-omics analyses identify Anterior Gradient 2 (AGR2) as a pre-operative prognostic biomarker in PCa. Through the drug library screening, we describe crizotinib as a selective compound for malignant PCa primary cells. We further perform the pharmacoproteome analysis and identify 14,372 significant protein-drug correlations. Surprisingly, the diminished AGR2 enhances the inhibition activity of crizotinib via ALK/c-MET-AKT axis activation which is validated by PC3 and xenograft model. Our integrated multi-omics approach yields a comprehensive understanding of PCa biomarkers and pharmacological responses, allowing for more precise diagnosis and therapies.

Investigation of targets and anticancer mechanisms of covalently acting natural products by functional proteomics.

Eriocalyxin B (EB), 17-hydroxy-jolkinolide B (HJB), parthenolide (PN), xanthatin (XT) and andrographolide (AG) are terpenoid natural products with a variety of promising antitumor activities, which commonly bear electrophilic groups (α,ß-unsaturated carbonyl groups and/or epoxides) capable of covalently modifying protein cysteine residues. However, their direct targets and underlying molecular mechanisms are still largely unclear, which limits the development of these compounds. In this study, we integrated activity-based protein profiling (ABPP) and quantitative proteomics approach to systematically characterize the covalent targets of these natural products and their involved cellular pathways. We first demonstrated the anti-proliferation activities of these five compounds in triple-negative breast cancer cell MDA-MB-231. Tandem mass tag (TMT)-based quantitative proteomics showed all five compounds commonly affected the ubiquitin mediated proteolysis pathways. ABPP platform identified the preferentially modified targets of EB and PN, two natural products with high anti-proliferation activity. Biochemical experiments showed that PN inhibited the cell proliferation through targeting ubiquitin carboxyl-terminal hydrolase 10 (USP10). Together, this study uncovered the covalently modified targets of these natural products and potential molecular mechanisms of their antitumor activities.

Evaluation of Concurrent Chemoradiotherapy for Survival Outcomes in Patients With Synchronous Oligometastatic Esophageal Squamous Cell Carcinoma.

Importance: The optimal treatment for and potential benefit populations of synchronous oligometastatic esophageal squamous cell carcinoma (SOESCC) remain unclear. Objectives: To evaluate outcomes of concurrent chemoradiotherapy (CCRT) and to construct decision tree models for predicting the risk of progression and mortality in patients with SOESCC. Design, Setting, and Participants: This prognostic study included 532 patients with SOESCC who were treated at 2 cancer centers in China from January 2012 to December 2018 and consisted of a development cohort (n = 381) and a validation cohort (n = 151). Data were analyzed from March 2019 to December 2021. Exposures: All patients received chemotherapy alone or CCRT. Main Outcomes and Measures: The primary end points of the study were progression-free survival (PFS) and overall survival (OS), and the secondary end points were locoregional control and treatment-related toxic effects. Propensity score matching was performed to control potential confounding factors. Cox regression was used to screen important explanatory variables. Decision trees for optimally partitioning patients were established using recursive partitioning analysis and were then subjected to internal and independent external validation. Results: Among the 532 patients (median [range] age, 63 [32-82] years; 367 men [69.0%]), 292 patients received chemotherapy alone and 240 patients underwent CCRT. With a median (IQR) follow-up time of 37.0 (21.6-55.8) months, CCRT was associated with improved objective response rate (139 of 240 [57.9%] vs 123 of 292 [42.1%]; P < .001), median (IQR) PFS (9.7 [8.5-10.9] months vs 7.6 [6.6-8.6] months; P < .001), and median (IQR) OS (18.5 [16.1-20.9] months vs 15.2 [13.6-16.8] months; P < .001) compared with chemotherapy alone. Propensity score matching analysis verified the results. Cox multivariate analysis indicated that treatment modality (CCRT vs chemotherapy alone) was an independent prognostic factor related to PFS (hazard ratio, 0.69; 95% CI, 0.57-0.83; P < .001) and OS (hazard ratio, 0.75; 95% CI, 0.61-0.93; P = .008). The final decision trees divided patients with SOESCC into low-, intermediate-, and high-risk groups in both the internal and external validations, and the corresponding cumulative risk function curves had significant differences (all P < .001). Time-dependent maximum areas under receiver operating curves of decision trees for progression risk at 3 years and mortality risk at 5 years were 0.820 (95% CI, 0.693-0.948) and 0.894 (95% CI, 0.822-0.966), respectively. Calibration curves also demonstrated that the decision trees had favorable performance of risk stratification. Conclusions and Relevance: In this study, CCRT vs chemotherapy alone as a first-line treatment for patients with SOESCC had superior survival. Patients with low risk had promising long-term survival based on the current treatment modality. The predictive information of the decision tree could provide accurate decision-making for the management of patients with SOESCC.

Preparation of a quartz microbalance sensor based on molecularly imprinted polymers and its application in formaldehyde detection.

Quartz crystal microbalances (QCMs) have been widely used in the food industry, environmental monitoring, and biomedicine. Here, a molecularly imprinted QCM sensor was prepared and used for formaldehyde detection. Using polyvinyl chloride as the embedding material and tetrahydrofuran as the solvent, a QCM electrode was modified with HCHO molecularly imprinted polymers (HCHO-MIPs). The detection conditions of the sensor were optimized, and its selectivity was investigated. The theoretical calculation results revealed that the acrylamide and pentaerythritol triacrylate were potential candidate functional monomer and cross-linking agent, respectively, in the preparation of HCHO-MIPs with high adsorbability, superselectivity, and stability. According to the calculated results, a sensor had been prepared. When the pH was 7, the added mass of the HCHO-MIPs (or NIPs) was 20 mg, and the amount of PVC coating was 20 µL, the sensor exhibited good adsorption, selectivity, repeatability, high sensitivity, high accuracy, and a short response time. The lowest detection limit was 10.72 ng mL-1. The sensor exhibited higher selectivity for HCHO than for propionaldehyde and benzaldehyde. The HCHO contents in fresh shrimp samples were detected using the sensor for four cycles, and the detection rates were in the range of 97.56-98.60%. This study provided a theoretical and experimental basis for the rapid detection of HCHO.

[Optimization and evaluation of protein C-terminal peptide enrichment strategy based on arginine cleavage].

As unique biomarkers, protein C-termini are involved in various biological processes such as protein trafficking, subcellular relocation, and signal transduction. Dysregulation of protein C-terminal status is critical during the development of various diseases, including cardiovascular, neurodegenerative, and metabolic diseases and cancer. Thus, global profiling of protein C-termini is of great value in providing mechanistic insight into biological or pathological processes, as well as for identifying potential new targets for therapeutic treatment. Polymer-based negative enrichment is a prominent C-terminomics strategy with advantages of universal applicability and parallel sample preparation. Compared with other methods of such a strategy, the profiling depth of the approaches based on enzymatic cleavage of Arg residues still needs to be improved. This greatly limits our understanding of the physiological functions and molecular mechanisms of C-termini. To add a more powerful tool for C-terminomics, Arg cleavage-based negative enrichment C-terminomics was optimized and evaluated. First, the sample preparation process was optimized. A one-pot enrichment platform based on a V-shaped filter was established, which reduced sample loss, avoided cross-contamination between reactions, and shortened sample preparation time. In addition, the protein-level acetylation conditions were investigated with the optimal labeling conditions as follows: triple coupling using 5 mmol/L Ac-NHS at pH 7.0 and 500 mmol/L ammonium for 15 min provided minimized acetylation rates (acetylation labeling efficiencies of Ser, Thr, and Tyr were lower than 4%, 2%, and 1%, respectively), along with the highest peptide-spectrum match number and satisfactory Lys labeling efficiency (up to 98%). These optimized conditions would not only minimize acetylation, but also facilitate the identification of C-terminal peptides. Second, it was speculated that the unexpected low identification rate was primarily caused by the interference of the large number of organic compounds accumulated during the peptide-level reactions, including reagents, organic buffering agents, and their complex side-reaction products. Therefore, the conditions for StageTip-based fractionation, including pH, the amount of Empore C18 beads, and the number of fractions, were optimized. As a result, by separating the sample enriched from 300 µg proteome into seven fractions, sample complexity was largely decreased and a total of 696 C-termini were identified in duplicates from strict data filtration, that is, percolator false discovery rate (FDR)<0.01, ion score≥20, and C-terminal amidation by ethanolamine. If only peptide FDR<0.01 was considered, the identified C-termini further increased to 933, which was among the largest C-terminome datasets obtained from the polymer-based strategy. Furthermore, compared with the results of a previous study, the optimized method would be a practical strategy for broader C-terminome coverage. Finally, to further broaden the coverage of the sub-C-terminome generated by Arg-specific cleavage, this study explored a new method in which ArgN-specific cleavage (cleavage at the N-terminal of Arg by LysargiNase) was combined with different N-terminal protections (dimethylation and acetylation). Among all the combinations, the additional use of the "LysargiNase+N-terminal acetylation" method increased 47% more identifications of unique C-termini on the basis of "trypsin+N-terminal demethylation" and the two covered 87% of the total C-termini. Therefore, the parallel use of the two methods would further expand the coverage of Arg-cleaved C-terminal peptides. With the analysis of the physicochemical properties of the peptides identified by the two methods, the reason why the C-terminal peptides identified by different strategies are complementary was explained. In conclusion, in this study, the optimized C-terminomics platform can deeply profile Arg cleavage-generated C-terminal peptides using a polymer-based approach. This method provides a powerful tool for the global characterization of protein C-termini.

Preoperative Chemotherapy for Limited-stage Small Cell Carcinoma of the Esophagus.

BACKGROUND: The optimal treatment approach for limited-stage small cell carcinoma of the esophagus remains uncertain. This study aimed to evaluate the efficacy and safety of preoperative chemotherapy in combination with surgery vs upfront surgery in those patients. METHODS: From June 2001 to June 2015, a total of 280 patients with limited-stage small cell carcinoma of the esophagus were screened from 60 131 patients with esophageal cancer. Outcome analysis of those patients who underwent preoperative chemotherapy in combination with surgery or upfront surgery was conducted. The primary end point was overall survival, and secondary end points included progression-free survival and safety. RESULTS: Of the 280 patients, 200 were men (71.4%), the median age was 64 years (range, 42-75 years), 171 patients (61.1%) patients had preoperative chemotherapy in combination with surgery, and 109 patients (38.9%) underwent upfront surgery. A pathologic complete response rate of 8.8% was noted in patients who received preoperative chemotherapy. Compared with the upfront surgery group, the preoperative chemotherapy group had a better median overall survival (26.0 months vs 19.5 months, respectively; hazard ratio, 0.69; 95% CI, 0.51 to 0.92; P = .011) and a prolonged progression-free survival (16.0 months vs 13.0 months, respectively; hazard ratio, 0.75; 95% CI, 0.57 to 0.99; P = .039). Postoperative complications and peritreatment mortality were comparable between both groups. CONCLUSIONS: Compared with upfront surgery, preoperative chemotherapy in combination with surgery improves overall survival in patients with limited-stage small cell carcinoma of the esophagus.

Dysfunction of apoptosis and autophagy correlates with local recurrence in esophageal squamous cell carcinoma after definitive chemoradiation.

OBJECTIVE: Definitive chemoradiotherapy (dCRT) is one of the standard treatments for esophageal squamous cell carcinoma (ESCC), but local recurrence is the main cause of treatment failure. The changes in apoptosis and autophagy in recurrent tumors of patients with ESCC following dCRT have been poorly estimated. Thus, this study aimed to investigate the expressions of key regulators of apoptosis and autophagy in matched paired samples of primary and recurrent ESCC. METHODS: The medical records of patients with locally advanced ESCC who developed local recurrence after dCRT were reviewed, and the expression profiling of apoptosis-related genes, cell apoptosis, autophagy and autophagy-related proteins were detected in normal esophageal squamous epithelium and paired samples of primary and recurrent ESCC. RESULTS: A total of 126 patients were enrolled, and 52.4% of them had stage III disease. The 1-, 3- and 5-year local recurrence-free survival (LRFS) rates were 54.8, 19.8 and 14.3%, respectively, with a median LRFS of 13.0 months. Patients with T2 tumor or stage II disease showed a significantly prolonged LRFS compared with that of patients with T3-4 tumor or stage III disease. The Apoptotic Machinery key genes expression profiling identified 5 upregulated and 7 downregulated apoptosis-related genes in recurrent tumors compared with their expression levels in the matched primary ESCC tumors. High expression of CD40, TRAF4 and BCL2A1, and low expression of CARD6 and TNFRSF21 were associated with increased risk of early local recurrence after dCRT. No differences in apoptotic index between primary and recurrent samples were detected. However, typical morphological features of autophagosomes and elevated LC3-II protein expression were detected in recurrent tumor samples, and positive LC3-II expression was correlated with increased risk of early local recurrence. CONCLUSION: Our findings indicated that apoptosis and autophagy dysfunction correlated with early local recurrence in patients with locally advanced ESCC receiving dCRT. Further studies are necessary to understand the biology of tumor recurrence in esophageal cancer.

Synergistic anti-tumor effect of anti-PD-L1 antibody cationic microbubbles for delivery of the miR-34a gene combined with ultrasound on cervical carcinoma.

This study explored the synergistic effect of anti-PD-L1 antibody cationic microbubbles (MBs) for delivery of the miR-34a gene combined with ultrasound in inhibiting the cervical cancer. H&E stain, TUNEL, immunohistochemistry and RT-PCR were used to detect the change of apoptosis regulatory factors, and immunofluorescence, Flow cytometry and LDH assays were applied to evaluate the changing of immunomodulatory. In this experiment the PD-L1 Ab/miR-34a-MBs were prepared successfully. The cell targeting assay showed that U14 cells were surrounded by the PD-L1 Ab/miR-34a-MBs and microbubbles had well contrast imaging capability in vivo. With the irradiation power was 1 W/cm2 and the irradiation time was 25 s, the gene transfection efficiency was the highest using EGFP plasmid lorded microbubbles. In vivo anti-tumor assays, the PD-L1 Ab/miR-34a-MBs showed a great potential in inhibiting tumor growth with a TGI of >50%. PD-L1 Ab/miR-34a-MBs treatment enhanced the anti-tumor effect compared with that induced by PD-L1 Ab or miR-34a alone. Firstly, PD-L1 Ab/miR-34a-MBs could gather miR-34a with high-concentration aggregation and releasing around the cervical cancer, which takes a significant role in promoting apoptosis by downregulated Bcl-2 and upregulated Bax. Furthermore, combination therapy was found to augment the activation of T lymphocytes proliferation and increase CD8+ T cells infiltration, to enhance antitumor immune killing effect. The anti-PD-L1 antibody microbubbles for delivery miR-34a gene with ultrasound were considered to be a promising combination therapy regimen via initiating apoptotic mechanism of the tumor and anti-tumor immune regulation.