Efficacy and predictive factors of transarterial chemoembolization combined with lenvatinib plus programmed cell death protein-1 inhibition for unresectable hepatocellular carcinoma

BACKGROUND The efficacy and safety of transarterial chemoembolization(TACE)combined with lenvatinib plus programmed cell death protein-1(PD-1)for unresectable hepato-cellular carcinoma(HCC)have rarely been evaluated and it is unknown which factors are related to efficacy.AIM To evaluate the efficacy and independent predictive factors of TACE combined with lenvatinib plus PD-1 inhibitors for unresectable HCC.METHODS This study retrospectively enrolled patients with unresectable HCC who received TACE/lenvatinib/PD-1 treatment between March 2019 and April 2022.Overall survival(OS)and progression-free survival(PFS)were determined.The objective response rate(ORR)and disease control rate(DCR)were evaluated in accordance with the modified Response Evaluation Criteria in Solid Tumors.Additionally,the prognostic factors affecting the clinical outcome were assessed.RESULTS One hundred and two patients were enrolled with a median follow-up duration of 12.63 months.The median OS was 26.43 months(95%CI:17.00-35.87),and the median PFS was 10.07 months(95%CI:8.50-11.65).The ORR and DCR were 61.76%and 81.37%,respectively.The patients with Barcelona Clinic Liver Cancer Classification(BCLC)B stage,early neutrophil-to-lymphocyte ratio(NLR)response(decrease),or early alpha-fetoprotein(AFP)response(decrease>20%)had superior OS and PFS than their counterparts.CONCLUSION This study showed that TACE/lenvatinib/PD-1 treatment was well tolerated with encouraging efficacy in patients with unresectable HCC.The patients with BCLC B-stage disease with early NLR response(decrease)and early AFP response(decrease>20%)may achieve better clinical outcomes with this triple therapy.

Quercetin Alleviates Lipopolysaccharide-Induced Cardiac Inflammation via Inhibiting Autophagy and Programmed Cell Death

Objective The aim of this study is to explore the potential modulatory role of quercetin against Endotoxin or lipopolysaccharide(LPS)induced septic cardiac dysfunction.Methods Specific pathogen-free chicken embryos(n=120)were allocated untreated control,phosphate buffer solution(PBS)vehicle,PBS with ethanol vehicle,LPS(500 ng/egg),LPS with quercetin treatment(10,20,or 40 nmol/egg,respectively),Quercetin groups(10,20,or 40 nmol/egg).Fifteenday-old embryonated eggs were inoculated with abovementioned solutions via the allantoic cavity.At embryonic day 19,the hearts of the embryos were collected for histopathological examination,RNA extraction,real-time polymerase chain reaction,immunohistochemical investigations,and Western blotting.Results They demonstrated that the heart presented inflammatory responses after LPS induction.The LPS-induced higher mRNA expressions of inflammation-related factors(TLR4,TNFα,MYD88,NF-κB1,IFNγ,IL-1β,IL-8,IL-6,IL-10,p38,MMP3,and MMP9)were blocked by quercetin with three dosages.Quercetin significantly decreased immunopositivity to TLR4 and MMP9 in the treatment group when compared with the LPS group.Quercetin significantly decreased protein expressions of TLR4,IFNγ,MMP3,and MMP9 when compared with the LPS group.Quercetin treatment prevented LPS-induced increase in the mRNA expression of Claudin 1 and ZO-1,and significantly decreased protein expression of claudin 1 when compared with the LPS group.Quercetin significantly downregulated autophagyrelated gene expressions(PPARα,SGLT1,APOA4,AMPKα1,AMPKα2,ATG5,ATG7,Beclin-1,and LC3B)and programmed cell death(Fas,Bcl-2,CASP1,CASP12,CASP3,and RIPK1)after LPS induction.Quercetin significantly decreased immunopositivity to APOA4,AMPKα2,and LC3-II/LC3-I in the treatment group when compared with the LPS group.Quercetin significantly decreased protein expressions of AMPKα1,LC3-I,and LC3-II.Quercetin significantly decreased the protein expression to CASP1 and CASP3 by immunohistochemical investigation or Western blotting in treatment group when compared with LPS group.Conclusion Quercetin alleviates cardiac inflammation induced by LPS through modulating autophagy,programmed cell death,and myocardiocytes permeability.

Pretreatment can alleviate programmed cell death in mesenchymal stem cells

In this editorial,we delved into the article titled“Cellular preconditioning and mesenchymal stem cell ferroptosis.”This groundbreaking study underscores a pivotal discovery:Ferroptosis,a type of programmed cell death,drastically reduces the viability of donor mesenchymal stem cells(MSCs)after engraftment,thereby undermining the therapeutic value of cell-based therapies.Furthermore,the article proposes that by manipulating ferroptosis mechanisms through preconditioning,we can potentially enhance the survival rate and functionality of MSCs,ultimately amplifying their therapeutic potential.Given the crucial role ferroptosis plays in shaping the therapeutic outcomes of MSCs,we deem it im-perative to further investigate the intricate interplay between programmed cell death and the therapeutic effectiveness of MSCs.

Roles of the tumor microenvironment in the resistance to programmed cell death protein 1 inhibitors in patients with gastric cancer

Despite the continuous developments and advancements in the treatment of gastric cancer(GC),which is one of the most prevalent types of cancer in China,the overall survival is still poor for most patients with advanced GC.In recent years,with the progress in tumor immunology research,attention has shifted toward immunotherapy as a therapeutic approach for GC.Programmed cell death protein 1(PD-1)inhibitors,as novel immunosuppressive medications,have been widely utilized in the treatment of GC.However,many patients are still resistant to PD-1 inhibitors and experience recurrence in the advanced stages of PD-1 immunotherapy.To reduce the occurrence of drug resistance and recurrence in GC patients receiving PD-1 immunotherapy,to maximize the clinical activity of immunosuppressive drugs,and to elicit a lasting immune response,it is essential to research the tumor microenvironment mechanisms leading to PD-1 inhibitor resistance in GC patients.This article reviews the progress in studying the factors influencing the resistance to PD-1 inhibitors in the GC tumor microenvironment,aiming to provide insights and a basis for reducing resistance to PD-1 inhibitors for GC patients in the future.

Efficacy of chemotherapy containing bevacizumab in patients with metastatic colorectal cancer according to programmed cell death ligand 1

BACKGROUND Bevacizumab,an anti-vascular endothelial growth factor(VEGF)monoclonal antibody,inhibits angiogenesis and reduces tumor growth.Serum VEGF-C,lactate dehydrogenase,and inflammatory markers have been reported as predictive markers related to bevacizumab treatment.Programmed cell death ligand 1(PD-L1)could act upon VEGF receptor 2 to induce cancer cell angiogenesis and metastasis.AIM To investigate the efficacy of bevacizumab-containing chemotherapy in patients with metastatic colorectal cancer(CRC)according to the expression of PD-L1.METHODS This analysis included CRC patients who received bevacizumab plus FOLFOX or FOLFIRI as first-line therapy between June 24,2014 and February 28,2022,at Samsung Medical Center(Seoul,South Korea).Analysis of patient data included evaluation of PD-L1 expression by the combined positive score(CPS).We analyzed the efficacy of bevacizumab according to PD-L1 expression status in patients with CRC.RESULTS A total of 124 patients was included in this analysis.Almost all patients were treated with bevacizumab plus FOLFIRI or FOLFOX as the first-line chemotherapy.While 77%of patients received FOLFOX,23%received FOLFIRI as backbone first-line chemotherapy.The numbers of patients with a PD-L1 CPS of 1 or more,5 or more,or 10 or more were 105(85%),64(52%),and 32(26%),respectively.The results showed no significant difference in progression-free survival(PFS)and overall survival(OS)with bevacizumab treatment between patients with PDL1 CPS less than 1 and those with PD-L1 CPS of 1 or more(PD-L1<1%vs PD-L1≥1%;PFS:P=0.93,OS:P=0.33),between patients with PD-L1 CPS less than 5 and of 5 or more(PD-L1<5%vs PD-L1≥5%;PFS:P=0.409,OS:P=0.746),and between patients with PD-L1 CPS less than 10 and of 10 or more(PD-L1<10%vs PD-L1≥10%;PFS:P=0.529,OS:P=0.568).CONCLUSION Chemotherapy containing bevacizumab can be considered as first-line therapy in metastatic CRC irrespective of PD-L1 expression.

Drug-eluting beads chemoembolization combined with programmed cell death 1 inhibitor and lenvatinib for large hepatocellular carcinoma

BACKGROUND The combination of transarterial chemoembolization(TACE),lenvatinib,and programmed cell death 1(PD-1)inhibitor has been widely used in the treatment of advanced hepatocellular carcinoma(HCC)and has achieved promising results.However,there are few studies comparing whether drug-eluting beads TACE(DTACE)can bring more survival benefits to patients with large HCC compared to conventional TACE(C-TACE)in this triplet therapy.AIM To compare the efficacy and adverse events(AEs)of triple therapy comprising DTACE,PD-1 inhibitors,and lenvatinib(D-TACE-P-L)and C-TACE,PD-1 inhibitors,and lenvatinib(C-TACE-P-L)in patients with large HCC(maximum diameter≥5 cm),and analyze the prognostic factors.METHODS Following a comprehensive review of our hospital’s medical records,this retrospective study included 104 patients:50 received D-TACE-P-L,and 54 received CTACE-P-L.We employed Kaplan-Meier estimation to assess the median progression-free survival(PFS)between the two groups,utilized Cox multivariate regression analysis to identify prognostic factors,and applied theχ2 test to evaluate AEs.RESULTS The objective response rate(ORR)and median PFS were significantly higher in the D-TACE-P-L group compared to the C-TACE-P-L group(ORR:66.0%vs 44.4%,P=0.027;median PFS:6.8 months vs 5.0 months,P=0.041).Cox regression analysis identified treatment option,portal vein tumor thrombus,and hepatic vein invasion as protective factors for PFS.AEs were comparable between the two CONCLUSION D-TACE-P-L may have significantly better PFS and ORR for large HCC,while exhibiting similar AEs to C-TACE-PL.

Effectiveness and tolerability of programmed cell death protein-1 inhibitor+chemotherapy compared to chemotherapy for upper gastrointestinal tract cancers

BACKGROUND The combination of programmed cell death protein-1(PD-1)inhibitor and che-motherapy is approved as a standard first-or second-line treatment in patients with advanced oesophageal or gastric cancer.However,it is unclear whether this combination is superior to chemotherapy alone.AIM To assess the comparative effectiveness and tolerability of combining PD-1 inhibitors with chemotherapy vs chemotherapy alone in patients with advanced gastric cancer,gastroesophageal junction(GEJ)cancer,or oesophageal carcinoma.METHODS We searched the PubMed and Embase databases for studies that compared the efficacy and tolerance of PD-1 inhibitors in combination with chemotherapy vs chemotherapy alone in patients with advanced oesophageal or gastric cancer.We employed either random or fixed models to analyze the outcomes of each clinical trial,en-compassing data on overall survival(OS),progression-free survival(PFS),objective response rate,and adverse events(AEs).RESULTS Nine phase 3 clinical trials(7016 advanced oesophageal and gastric cancer patients)met the inclusion criteria.Our meta-analysis demonstrated that the pooled PD-1 inhibitor+chemotherapy group had a significantly longer OS than the chemotherapy-alone group[hazard ratio(HR)=0.76,95%confidence interval(CI):0.71-0.81];the pooled PFS result was consistent with that of OS(HR=0.67,95%CI:0.61-0.74).The count of patients achieving an objective response in the PD-1 inhibitor+chemotherapy group surpassed that of the chemotherapy-alone group[odds ratio(OR)=1.86,95%CI:1.59-2.18].AE incidence was also higher in the combination-therapy group than in the chemotherapy-alone group,regardless of whether≥grade 3 only(OR=1.30,95%CI:1.07-1.57)or all AE grades(OR=1.88,95%CI:1.39-2.54)were examined.We performed a subgroup analysis based on the programmed death-ligand 1(PD-L1)combined positive score(CPS)and noted extended OS and PFS durations within the CPS≥1,CPS≥5,and CPS≥10 subgroups of the PD-1 inhibitor+chemotherapy group.CONCLUSION In contrast to chemotherapy alone,the combination of PD-1 inhibitor and chemotherapy appears to present a more favorable option for initial or subsequent treatment in patients with gastric cancer,GEJ tumor,or oesophageal cancer.This holds true particularly for individuals with PD-L1 CPS scores of≥5 and≥10.

Programmed cell death 1 inhibitor sintilimab plus concurrent chemoradiotherapy for locally advanced pancreatic adenocarcinoma

BACKGROUND Pancreatic adenocarcinoma,a malignancy that arises in the cells of the pancreas,is a devastating disease with unclear etiology and often poor prognosis.Locally advanced pancreatic cancer,a stage where the tumor has grown significantly but has not yet spread to distant organs,presents unique challenges in treatment.This article aims to discuss the current strategies,challenges,and future directions in the management of locally advanced pancreatic adenocarcinoma(LAPC).AIM To investigate the feasibility and efficacy of programmed cell death 1(PD-1)inhibitor sintilimab plus concurrent chemoradiotherapy for LAPC.METHODS Eligible patients had LAPC,an Eastern cooperative oncology group performance status of 0 or 1,adequate organ and marrow functions,and no prior anticancer therapy.In the observation group,participants received intravenous sintilimab 200 mg once every 3 wk,and received concurrent chemoradiotherapy(concurrent conventional fractionated radiotherapy with doses planning target volume 50.4 Gy and gross tumor volume 60 Gy in 28 fractions and oral S-140 mg/m2 twice daily on days 1-14 of a 21-d cycle and intravenous gemcitabine 1000 mg/m2 on days 1 and 8 of a 21-d cycle for eight cycles until disease progression,death,or unacceptable toxicity).In the control group,participants only received concurrent chemoradiotherapy.From April 2020 to November 2021,64 participants were finally enrolled with 34 in the observation group and 30 in the control group.RESULTS Thirty-four patients completed the scheduled course of chemoradiotherapy,while 32(94.1%)received sintilimab plus concurrent chemoradiotherapy with 2 patients discontinuing sintilimab in the observation group.Thirty patients completed the scheduled course of chemoradiotherapy in the control group.Based on the Response Evaluation Criteria in Solid Tumors guidelines,the analysis of the observation group revealed that a partial response was observed in 11 patients(32.4%),stable disease was evident in 19 patients(55.9%),and 4 patients(11.8%)experienced progressive disease;a partial response was observed in 6(20.0%)patients,stable disease in 18(60%),and progressive disease in 6(20%)in the control group.The major toxic effects were leukopenia and nausea.The incidence of severe adverse events(AEs)(grade 3 or 4)was 26.5%(9/34)in the observation group and 23.3%(7/30)in the control group.There were no treatment-related deaths.The observation group demonstrated a significantly longer median overall survival(22.1 mo compared to 15.8 mo)(P<0.05)and progression-free survival(12.2 mo vs 10.1 mo)(P<0.05)in comparison to the control group.The occurrence of severe AEs did not exhibit a statistically significant difference between the observation group and the control group(P>0.05).CONCLUSION Sintilimab plus concurrent chemoradiotherapy was effective and safe for LAPC patients,and warrants further investigation.

Mitochondrial dysfunction and programmed cell death in osteosarcoma

Osteosarcoma is the most prevalent primarymalignant bone tumor,primarily affecting adolescents aged 15–25 years.It is characterized by a high recurrence rate,poor prognosis,and lack of important biomarkers.Significant mitochondrial dysfunction in osteosarcoma cells has been widely reported by recent studies.Dysfunctional mitochondria occupy an important position in cellularmetabolic reprogramming,immune microenvironment regulation,and programmed cell death.Therefore,targeting mitochondrial dysfunction may represent a new mechanism to overcome therapeutic barriers in the treatment of osteosarcoma and provides crucial target molecules for further development of targeted therapies and immunotherapies.The present article summarizes the recent reports of mitochondrial dysfunction in osteosarcoma and links it to various programmed cell death mechanisms,aiming to provide the basis for further clinical practice.

Programmed Cell Death During Secondary Xylem Differentiation in Eucommia ulmoides

Programmed cell death (PCD) during secondary xylem differentiation in Eucommia ulmoides Oliv. was examined using electron microscopy and by investigation of DNA fragmentation and degradation of caspase-like proteases (CLPs). DNA ladders were detected in developing secondary xylem by gel electrophoresis. DNA fragmentation was further confirmed by using the TdT-mediated dUTP nick-end labeling (TUNEL) method. Western blotting analysis showed that CLPs (caspase-8- and caspase-3-like proteases) and PARP (poly (ADP-ribose) polymerase) were degraded during secondary xylem differentiation. The results thus indicated that secondary xylem differentiation in E ulmoides was a typical process of PCD and the degradation of CLPs might be a constitutive PCD event during secondary xylem differentiation.

Ultrastructural Features of Nucleus Degradation During Programmed Cell Death of Starchy Endosperm Cells in Rice

Ultrastructural features of nucleus degradation during programmed cell death (PCD) of starchy endosperm cells in rice ( Oryza sativa L.) were observed using transmission electron microscopy. Several distinct morphological features of PCD have been found in the developing starchy endosperm cells, e.g. nucleus deformation, chromatin condensation, nuclear envelope disruption, and nuclear matrix leakage. DNA ladder displayed a smear of large DNA fragments from nucleus and evident bands of small DNA fragments (140-180 bp) from both nucleus and cytoplasm. In contrast with the rapid nucleus degradation, cell organelles in cytoplasm, such as rough endoplasmic reticulum, amyloplast, and mitochondrion, maintained their metabolic functions for a longer time. Seed reserves were continually synthesized and accumulated in the starchy endosperm cells despite the nucleus degradation during the PCD process. These results suggest that starchy endosperm cells remain active during reserve material synthesis and accumulation in the PCD process. The specific relationships between nucleus and cytoplasm in the developing endosperm cells and the morphological changes of nucleus in the endosperm PCD process were also discussed.

Leveraging diverse cell-death patterns to predict the clinical outcome of immune checkpoint therapy in lung adenocarcinoma:Based on muti-omics analysis and vitro assay

Advanced LUAD shows limited response to treatment including immune therapy.With the development of sequencing omics,it is urgent to combine high-throughput multi-omics data to identify new immune checkpoint therapeutic response markers.Using GSE72094(n=386)and GSE31210(n=226)gene expression profile data in the GEO database,we identified genes associated with lung adenocarcinoma(LUAD)death using tools such as“edgeR”and“maftools”and visualized the characteristics of these genes using the“circlize”R package.We constructed a prognostic model based on death-related genes and optimized the model using LASSO-Cox regression methods.By calculating the cell death index(CDI)of each individual,we divided LUAD patients into high and low CDI groups and examined the relationship between CDI and overall survival time by principal component analysis(PCA)and Kaplan-Meier analysis.We also used the“ConsensusClusterPlus”tool for unsupervised clustering of LUAD subtypes based on model genes.In addition,we collected data on the expression of immunomodulatory genes and model genes for each cohort and performed tumor microenvironment analyses.We also used the TIDE algorithm to predict immunotherapy responses in the CDI cohort.Finally,we studied the effect of PRKCD on the proliferation and migration of LUAD cells through cell culture experiments.The study utilized the TCGA-LUAD cohort(n=493)and identified 2,901 genes that are differentially expressed in patients with LUAD.Through KEGG and GO enrichment analysis,these genes were found to be involved in a wide range of biological pathways.The study also used univariate Cox regression models and LASSO regression analyses to identify 17 candidate genes that were best associated with mortality prognostic risk scores.By comparing the overall survival(OS)outcomes of patients with different CDI values,it was found that increased CDI levels were significantly associated with lower OS rates.In addition,the study used unsupervised cluster analysis to divide 115 LUAD patients into two distinct clusters with significant differences in OS timing.Finally,a prognostic indicator called CDI was established and its feasibility as an independent prognostic indicator was evaluated by Cox proportional risk regression analysis.The immunotherapy efficacy was more sensitive in the group with high expression of programmed cell death models.Relationship between programmed cell death(PCD)signature models and drug reactivity.After evaluating the median inhibitory concentration(IC50)of various drugs in LUAD samples,statistically significant differences in IC50 values were found in cohorts with high and low CDI status.Specifically,Gefitinib and Lapatinib had higher IC50 values in the high-CDI cohort,while Olaparib,Oxaliplatin,SB216763,and Axitinib had lower values.These results suggest that individuals with high CDI levels are sensitive to tyrosine kinase inhibitors and may be resistant to conventional chemotherapy.Therefore,this study constructed a gene model that can evaluate patient immunotherapy by using programmed cell death-related genes based on muti-omics.The CDI index composed of these programmed cell death-related genes reveals the heterogeneity of lung adenocarcinoma tumors and serves as a prognostic indicator for patients.

Expression characteristics of peripheral lymphocyte programmed death 1 and FoxP3+ Tregs in gastric cancer during surgery and chemotherapy

BACKGROUND Programmed death 1(PD-1)and CD4^(+)CD25^(+)FoxP3^(+)expression in peripheral blood T-cells has been previously reported in various types of cancer.However,the specific variation tendency during surgery and chemotherapy,as well as their relationship in gastric cancer patients,still remain unclear.Understanding this aspect may provide some novel insights for future studies on tumor recurrence and tumor immune escape,and also serve as a reference for determining the optimal timing and dose of clinical anti-PD-1 antibodies.AIM To observe and analyze the expression characteristics of peripheral lymphocyte PD-1 and FoxP3^(+)regulatory T cells(FoxP3^(+)Tregs)before and after surgery or chemotherapy in gastric cancer patients.METHODS Twenty-nine stomach cancer patients undergoing chemotherapy after a D2 gastrectomy provided 10 mL peripheral blood samples at each phase of the perioperative period and during chemotherapy.This study also included 29 agematched healthy donors as a control group.PD-1 expression was detected on lymphocytes,including CD4^(+)CD8^(+)CD45RO^(+),CD4^(+)CD45RO^(+),and CD8^(+)CD45RO^(+)lymphocytes as well as regulatory T cells.RESULTS We observed a significant increase of PD-1 expression on immune subsets and a larger number of FoxP3^(+)Tregs in gastric cancer patients(P<0.05).Following D2 gastrectomy,peripheral lymphocytes PD-1 expression and the number of FoxP3^(+)Tregs notably decrease(P<0.05).However,during postoperative chemotherapy,we only observed a decrease in PD-1 expression on lymphocytes in the CD8^(+)CD45RO^(+)and CD8^(+)CD45RO^(+)populations.Additionally,linear correlation analysis indicated a positive correlation between PD-1 expression and the number of CD4^(+)CD45RO^(+)FoxP3high activated Tregs(aTregs)on the total peripheral lymphocytes(r=0.5622,P<0.0001).CONCLUSION The observed alterations in PD-1 expression and the activation of regulatory T cells during gastric cancer treatment may offer novel insights for future investigations into tumor immune evasion and the clinical application of anti-PD-1 antibodies in gastric cancer.

Immune-related adverse events induced by programmed death protein-1 inhibitors from the perspective of lymphoma immunotherapy

Lymphoma,which is highly malignant,stems from lymph nodes and lymphoid tissue.Lymphoma cells express programmed death-ligand 1/2(PD-L1/PD-L2),which binds with programmed cell death 1 protein(PD-1)to establish inhibitory signaling that impedes the normal function of T cells and allows tumor cells to escape immune system surveillance.Recently,immune checkpoint inhibitor immunotherapies such as PD-1 inhibitors(nivolumab and pembrolizumab)have been introduced into the lymphoma treatment algorithm and have shown remarkable clinical efficacy and greatly improve prognosis in lymphoma patients.Accordingly,the number of lymphoma patients who are seeking treatment with PD-1 inhibitors is growing annually,which results in an increasing number of patients developing immune-related adverse events(irAEs).The occurrence of irAEs inevitably affects the benefits provided by immunotherapy,particularly when PD-1 inhibitors are applied.However,the mechanisms and characteristics of irAEs induced by PD-1 inhibitors in lymphoma need further investigation.This review article summarizes the latest research advances in irAEs during treatment of lymphoma with PD-1 inhibitors.A comprehensive understanding of irAEs incurred in immunotherapy can help to achieve better efficacy with PD-1 inhibitors in lymphoma.

Morphological Changes in Nucellar Cells Undergoing Programmed Cell Death (PCD) During Pollen Chamber Formation in Ginkgo biloba

Programmed cell death (PCD) of the nucellar cells at the micropylar end is involved in pollen chamber morphogenesis in Ginkgo biloba L. A development-course observation of the morphological changes in the nucellar cells undergoing PCD to form pollen chamber was performed. During the PCD, the nucellar cells degraded their cellular components through an orderly progression. Through the vactiolation, the cytosol was engulfed by the enlarging vacuole, leaving out various organelles, which remained morphologically integrated. As the vacuolation continued, the vacuole collapsed with the breakage of the tonoplast and the cytosol disappeared completely. Organelles were subsequently destroyed. Ultimately, nucellar cells digested away all of their cytoplasm, leaving with cell walls. They became collapsed as the nucellus developed. Intracellular membranes were strikingly changed, playing a role in leading to cell death. Some of these noticeable changes were the appearance of multivesicular body, multicycle-like membranes, membrane-bounded bodies containing some organelles, tonoplast rupture and numerous vesicles. The dehiscence of the apical epidermis, resulting in the opening, appeared to have followed two different pathways with one involving a specific epidermal cell autolysis and the other by detachment from middle lamella of two neighboring epidermal cells without cell autolysis. The specific epidermal cells had been dead prior to the dehiscence of the apical epidermis, which marked the sites of the dehiscence followed. In view of the changes in the cellular morphology, a process of nucellar cell PCD in the course of the pollen chamber formation was demonstrated.

Natural course of chronic hepatitis B is characterized by changing patterns of programmed death type-1 of CD8-positive T cells

AIM:To investigate if and how programmed death type-1(PD-1)expression affects the natural course of hepatitis B virus(HBV)infection. METHODS:Sixty-four patients in different natural stages of chronic HBV infection were enrolled in this study.PD-1 expression in total T cells was detected by flow cytometry.Levels of total CD8+T cell responses and proliferation in relation to PD-1 expression levels were analyzed with intracellular staining and PD-1/ PD-L1 blockage. RESULTS:The PD-1 expression in T cells was dynamically changed during the natural course of chronic HBV infection,did not significantly increase in the immune tolerance phase,and returned to normal in the inactive virus carrier stage.Blockage of the PD-1/PD-L1 pathway could not affect the T-cell response in the immune tolerance and inactive virus carrier stages of chronic HBV infection.However,it could significantly restore the T-cell response in the immune clearance stage of chronic HBV infection.Furthermore,the PD-1 expression level in T cells was associated with the alanine aminotransferase level during the immune clearance stage of chronic HBV infection. CONCLUSION:The PD-l/PD-L1 pathway plays a different role in T-cell response during the natural course of chronic HBV infection.

Use of programmed cell death protein ligand 1 assay to predict the outcomes of non-small cell lung cancer patients treated with immune checkpoint inhibitors

The recent discovery of immune checkpoints inhibitors, especially anti-programmed cell death protein 1(PD-1)and anti-programmed cell death protein ligand 1(PD-L1) monoclonal antibodies, has opened new scenarios in the management of non-small cell lung cancer(NSCLC) and this new class of drugs has achieved a rapid development in the treatment of this disease. However, considering the costs of these drugs and the fact that only a subset of patients experience long-term disease control, the identification of predictive biomarkers for the selection of candidates suitable for treatment has become a priority. The research focused mainly on the expression of the PD-L1 receptor on both tumor cells and/or immune infiltrates determined by immunohistochemistry(IHC). However, different checkpoint inhibitors were tested, different IHC assays were used, different targets were considered(tumor cells, immune infiltrates or both) and different expression thresholds were employed in clinical trials. In some trials the assay was used prospectively to select the patients, while in other trials it was evaluated retrospectively. Some confusion emerges, which makes it difficult to easily compare the literature data and to translate them in practice management. This mini-review shows the possibilities and pitfalls of the PD-L1 expression to predict the activity and efficacy of anti PD1/PD-L1 monoclonal antibodies in the treatment of NSCLC.

Programmed cell death, antioxidant response and oxidative stress in wheat f lag leaves induced by chemical hybridization agent SQ-1

Male sterility induced by a chemical hybridization agent （CHA） is an important tool for utilizing crop heterosis. Leaves, especially the flag leaves, as CHA initial recipients play a decisive role in inducing male sterility. To investigate effects of different treatment times of CHA-SQ-1 used, morphological, biochemical and physiological responses of wheat flag leaves were detected in thistudy. CHA induced programmed cell death （PCD） as shown in terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling （TUNEL） and DNA laddering analysis. In the early phase, CHA-SQ-1 trig- gered organelle changes arid PCD in wheat leaves accompanied by excess production of reactive oxygen species （O2- and H202） and down-regulation of the activities of superoxide dismutase （SOD）, catalase （CAT） and guaiacol peroxidase （POD）. Meanwhile, leaf cell DNAs showed ladder-like patterns on agarose gel, indicating that CHA-SQ-1 led to the activation of the responsible endonuclease. The oxidative stress assays showed that lipid peroxidation was strongly activated and photosynthesis was obviously inhibited in SQ-l-induced leaves. However, CHA contents in wheat leaves gradually reduced along with the time CHA-SQ-1 applied. Young flags returned to an oxidative/antioxidative balance and ultimately developed into mature green leaves. These results provide explanation of the relations between PCD and anther abortion and practical application of CHA for hybrid breeding.

The clinical association of programmed cell death protein 4(PDCD4) with solid tumors and its prognostic significance:a meta-analysis

Background: Programmed cell death protein 4(PDCD4) is a novel tumor suppressor protein involved in pro?grammed cell death. Its association with cancer progression has been observed in multiple tumor models, but evidence supporting its association with solid tumors in humans remains controversial. This study aimed to determine the clinical signiicance and prognostic value of PDCD4 in solid tumors.Methods: A systematic literature review was performed to retrieve publications with available clinical informa?tion and survival data. The eligibility of the selected articles was based on the criteria of the Dutch Cochrane Centre proposed by the Meta?analysis Of Observational Studies in Epidemiology group. Pooled odds ratios(ORs), hazard ratios(HRs), and 95% conidence intervals(CIs) for survival analysis were calculated. Publication bias was examined by Begg's and Egger's tests.Results: Clinical data of 2227 cancer patients with solid tumors from 23 studies were evaluated. PDCD4 expression was signiicantly associated with the diferentiation status of head and neck cancer(OR 4.25, 95% CI 1.87–9.66) and digestive system cancer(OR 2.87, 95% CI 1.84–4.48). Down?regulation of PDCD4 was signiicantly associated with short overall survival of patients with head and neck(HR: 3.44, 95% CI 2.38–4.98), breast(HR: 1.86, 95% CI 1.36–2.54), digestive system(HR: 2.12, 95% CI 1.75–2.56), and urinary system cancers(HR: 3.16, 95% CI 1.06–9.41).Conclusions: The current evidence suggests that PDCD4 down?regulation is involved in the progression of several types of solid tumor and is a potential marker for solid tumor prognoses. Its clinical usefulness should be conirmed by large?scale prospective studies.

Reduced Expression of Programmed Cell Death 5 Protein in Tissue of Human Prostate Cancer

Objective To investigate the expression of programmed cell death 5 （PDCD5） in tissues of normal human prostate （NP）, benign prostatic hyperplasia （BPH）, and prostate cancer （PCa） in order to assess the clinical role of PDCD5 in PCa. Methods PDCD5 expression was determined by EnVision immunohistochemical staining in forma-lin-fixed and paraffin-embedded specimens obtained from 12 subjects with NP, 22 with BPH, and 22 with PCa. In addition, PCa cases were classified as low/middle-risk （Gleason sumS7） and high-risk （Gleason sum〉7） on the basis of Gleason grade. Positive expression rates and intensity of PDCD5 protein were observed under light microscope and analyzed with computer imaging technique. Expression of PDCD5 was compared among different prostatic tissues. Results The expression of PDCD5 was significantly lower in tissue of PCa than in tissues of NP and BPH （P〈0.01）. However, there was no significant difference in PDCD5 expression between tissues of NP and BPH. In addition, the expression of PDCD5 was further downregulated with the increase of Gleason sum in PCa. Conclusions By downregulating apoptosis, low PDCD5 expression may play an important role in the occurrence and development of PCa. PDCD5 is supposed to have a potential clinical value to be a new predictor of progression and target of gene therapy in PCa.