BACKGROUND The combination of anti-epidermal growth factor receptor(EGFR)therapy and chemotherapy is currently a preferred first-line treatment for patients with unre-sectable,RAS and BRAF wild-type,left-sided metasta...BACKGROUND The combination of anti-epidermal growth factor receptor(EGFR)therapy and chemotherapy is currently a preferred first-line treatment for patients with unre-sectable,RAS and BRAF wild-type,left-sided metastatic colorectal cancer(mCRC).Several studies have also demonstrated the benefit of anti-EGFR therapy in sub-sequent line settings for this patient population.However,direct evidence com-paring the effectiveness of frontline vs subsequent anti-EGFR therapy remains limited,leaving a crucial gap in guiding optimal treatment strategies.AIM To compare overall survival(OS)between frontline and subsequent anti-EGFR treatment in patients with unresectable,RAS and BRAF wild-type,left-sided mCRC.METHODS We retrospectively reviewed the medical records of mCRC patients treated at The King Chulalongkorn Memorial Hospital and Songklanagarind Hospital,Thailand,between January 2013 and April 2023.Patients were classified into two groups based on the sequence of their anti-EGFR treatment.The primary endpoint was OS.RESULTS Among 222 patients with a median follow-up of 29 months,no significant difference in OS was observed between the frontline and subsequent-line groups(HR 1.03,95%CI:0.73-1.46,P=0.878).The median OS was 35.53 months(95%CI:26.59-44.47)for the frontline group and 31.60 months(95%CI:27.83-35.37)for the subsequent-line group.In the subsequent-line group,71 patients(32.4%)who ultimately never received anti-EGFR therapy had a significantly worse median OS of 19.70 months(95%CI:12.87-26.53).CONCLUSION Frontline and subsequent-line anti-EGFR treatments provide comparable OS in unresectable,RAS/BRAF wild-type,left-sided mCRC patients,but early exposure is vital for those unlikely to receive subsequent therapy.展开更多
The reversing effect of wild-type PTEN gene on resistance of C 13K cells to cisplatin and its inhibitory effect on the phosphorylation of protein kinase B （AKT） were studied. The expression of PTEN mRNA and protein ...The reversing effect of wild-type PTEN gene on resistance of C 13K cells to cisplatin and its inhibitory effect on the phosphorylation of protein kinase B （AKT） were studied. The expression of PTEN mRNA and protein in OV2008 cells and C13K cells were semi-quantitatively detected by using RT-PCR and Western blotting. Recombinant eukaryotic expression plasmid containing human wild-type PTEN gene was transfected into C13K cells by lipofectamine2000. The expression of PTEN mRNA was monitored by RT-PCR and the expression of PTEN, Akt, p-Akt protein were ana- lyzed by Western blotting in PTEN-transfected and non-transfected C13K cells. Proliferation and chemosensitivity of cells to DDP were measured by MTT, and cell apoptosis was detected by flow cytometry after treatment with cisplatin. The expression of PTEN mRNA and protein in OV2008 cells were significantly higher than those in C13K cells. After transfection with PTEN gene for 48 h, the expression of PTEN mRNA and protein in C 13K cells were 2.04 ± 0.10, 0.94± 0.04 respectively and the expression of p-Akt protein （ 0.94± 0.07） was lower than those in control groups （1.68 ±0.14, 1.66± 0.10） （P〈 0.05）. The IC50 of DDP to C 13 K cells transfected with PTEN （7.2± 0.3 la mol/L） was obviously lower than those of empty-vector transfected cells and non-transfected cells （12.7±0.4 lamol/1, 13.0±0.3 lamol/L） （P〈0.05）. The apopototis ratio of wild-type PTEN-transfected, empty vector transfected and non-transfected C13K cells were （41.65___0.87）%, （18.61 ±0.70）% and （15.28±0.80）% respectively, and the difference was statistically significant （P〈0.05）. PTEN gene plays an important role in ovarian cancer multidrug resistance. Transfection of PTEN could increase the expression of PTEN and restore drug sensitivity to cisplatin in human ovarian cancer cell line C 13K with multidrug-resistance by decreasing the expression of p-Akt.展开更多
AIM:To construct eukaryotic expression plasmids of full-length Hepatitis B Virus(HBV) genotype C genome,which contain lamivudine-resistant mutants(YIDD,YVDD) or wild-type strain(YMDD) ,and to observe the expression of...AIM:To construct eukaryotic expression plasmids of full-length Hepatitis B Virus(HBV) genotype C genome,which contain lamivudine-resistant mutants(YIDD,YVDD) or wild-type strain(YMDD) ,and to observe the expression of HBV DNA and antigens [hepatitis B surface antigen(HBsAg) and hepatitis B e antigen(HBeAg) ] of the recombinant plasmids in HepG2 cells. METHODS:Three HBV full-length genomes were amplified from the plasmids pMD18T-HBV/YIDD,pMD18T-HBV/YVDD and pMD18T-HBV/YMDD,using PCR. Three recombinant plasmids were generated by inserting each of the PCR products into the eukaryotic expression vector pcDNA3.1(+) ,between the EcoRI and HindⅢ sites. After being characterized by restriction endonuclease digestion,and DNA sequence analysis,the recombinant plasmids were transfected into HepG2 cells. At 48 and 72 h post-transfection,the levels of intracellular viral DNA replication were detected by real-time PCR,and the expression of HBsAg and HBeAg in the cell culture supernatant was determined by ELISA. RESULTS:Restriction endonuclease digestion and DNA sequence analysis confirmed that the threerecombinant plasmids were correctly constructed. After transfecting the plasmids into HepG2 cells,high levels of intracellular viral DNA replication were observed,and HBsAg and HBeAg were secreted into the cell culture supernatant. CONCLUSION:Eukaryotic expression plasmids pcDNA3.1(+) -HBV/YIDD,pcDNA3.1(+) -HBV/YVDD or pcDNA3.1(+) -HBV/YMDD,which contained HBV genotype C full-length genome,were successfully constructed. After transfection into HepG2 cells,the recombinant plasmids efficiently expressed HBV DNA,HBsAg and HBeAg. Our results provide an experimental basis for the further study of HBV lamivudine-resistant mutants.展开更多
AIM: To clarify the biological role of stem cell factor (SCF)-mediated wild-type KIT receptor activation in gastrointestinal stromal tumor (GIST) growth. METHODS: The co-expression of wild-type KIT receptor and SCF wa...AIM: To clarify the biological role of stem cell factor (SCF)-mediated wild-type KIT receptor activation in gastrointestinal stromal tumor (GIST) growth. METHODS: The co-expression of wild-type KIT receptor and SCF was evaluated in 51 GIST samples using mutation analysis and immunohistochemistry, and the results were correlated with clinicopathological param- eters, including the mitotic count, proliferative index (Ki-67 immunohistochemical staining), mitotic index (phospho-histone H3 immunohistochemical staining) and apoptotic index (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling). Using primary cultured GIST cells, the effect of SCF-mediated wild-type KIT receptor activation was determined by western blotting, methyl thiazolyl tetrazolium (MTT), and apoptosis assays. RESULTS: We found that wild-type KIT receptor and SCF protein were expressed in 100% and 76.5% of the 51 GIST samples, respectively, and the co-expression of wild-type KIT receptor and SCF was associated with known indicators of poor prognosis, including larger tumor size (P = 0.0118), higher mitotic count (P = 0.0058), higher proliferative index (P = 0.0012), higher mitotic index (P = 0.0282), lower apoptosis index (P = 0.0484), and increased National Institutes of Health risk level (P = 0.0012). We also found that the introduction of exogenous SCF potently increased KIT kinase activity, stimulated cell proliferation (P < 0.01) and inhibited apoptosis (P < 0.01) induced by serum starvation, while a KIT immunoblocking antibody suppressed proliferation (P = 0.01) and promoted apoptosis (P < 0.01) in cultured GIST cells. CONCLUSION: SCF-mediated wild-type KIT receptor activation plays an important role in GIST cell growth. The inhibition of SCF-mediated wild-type KIT receptor activation may prove to be particularly important for GIST therapy.展开更多
The goal of this study was to determine whether mutation of the Mn-binding site of wild-type recombinant Phlebia radiata manganese peroxidase 3 affected the pH-dependence kinetic parameters. pH range investigated was ...The goal of this study was to determine whether mutation of the Mn-binding site of wild-type recombinant Phlebia radiata manganese peroxidase 3 affected the pH-dependence kinetic parameters. pH range investigated was 2.5 – 12.0. The catalytic efficiency of the mutant enzymes at high and low pH in comparison to the wild-type was investigated using standard rPr-MnP3 protocol. Wild-type recombinant Phlebia radiata MnP3 enzyme showed optimal activity with Mn (II) as substrate at pH 5.0 and remained moderately active (approximately 40%) in the pH range of 6.0 - 9.0. The rPr-MnP3 mutants’ maximum activity ranged between 5.5 and 8.0. Wild-type and mutants rPr-MnP3 enzymes exhibited a similar pH profile with optimum pH of 3.0 for ABTS oxidation. Mutation has severely decreased the catalytic efficiency for Mn (II) oxidation at pH 5.0. The rPr-MnP3 enzymes showed enhanced affinity for Mn (II) at alkaline pH and a more alkaline range for catalysis than ever reported for any Manganese Peroxidase. This study reveals that at higher pH, rPr-MnP3 can function with alternative ligands in the Mn (II) site and does not have an absolutely obligate requirement for an all carboxylate ligand set. These results further strongly confirm that Mn<sup>2+</sup> binding site is the only productive catalytic site for Mn (II) oxidation.展开更多
BACKGROUND Wild-type transthyretin amyloidosis(ATTRwt)is the most common form of transthyretin amyloid cardiomyopathy,occurring mostly over age of 60 years(mean age of 80 years).Mean survival without treatment is 3.6 ...BACKGROUND Wild-type transthyretin amyloidosis(ATTRwt)is the most common form of transthyretin amyloid cardiomyopathy,occurring mostly over age of 60 years(mean age of 80 years).Mean survival without treatment is 3.6 years,making early detection imperative.We report an unusual case of a 58-year-old patient with ATTRwt cardiomyopathy requiring heart transplantation.CASE SUMMARY A 58-year-old male presented with progressive fatigue,shortness of breath,weight gain,leg swelling,orthopnoea,and paroxysmal nocturnal dyspnoea for several months.Approximately ten months before this clinical presentation,the patient had first received a diagnosis of heart failure with reduced ejection fraction(EF)of 15% to 20%.The patient was started on appropriate guidelinedirected medical therapy with only mild improvement in his EF.Upon further investigation,echocardiogram,technetium pyrophosphate scan(Tc PYP),and cardiac magnetic resonance imaging(cMRI)suggested a diagnosis of amyloidosis,and ATTRwt was subsequently confirmed with native heart tissue biopsy,congo red staining,liquid chromatography-tandem mass spectrometry,and genetic testing.The patient was successfully treated with heart transplantation and is doing well post-transplant.CONCLUSION Wild-type ATTR amyloidosis should be kept on differentials in all patients(even less than 60 years old)with non-ischemic cardiomyopathy,especially in the setting of increased ventricular wall thickness and other classic echocardiogram,cMRI,and Tc PYP findings.Early diagnosis and management can be consequential in improving patient outcomes.展开更多
K-ras wild-type carcinoma is a tumour that is sensitive to treatment with anti-cancer and anti-EGFR drugs: the combination of Cetuximab and Panitumumab with chemotherapy (Cetuximab) or as a single therapy (Panitumumab...K-ras wild-type carcinoma is a tumour that is sensitive to treatment with anti-cancer and anti-EGFR drugs: the combination of Cetuximab and Panitumumab with chemotherapy (Cetuximab) or as a single therapy (Panitumumab). Case Report: The clinical case presented here refers to a 68-year-old patient who had been diagnosed with adenocarcinoma of the recto sigmoid with pelvic recurrence three years after surgery. The patient had a severe co-morbidity: correlated B-type liver cirrhosis. First-line chemotherapy was begun with Oxaliplatin plus Capecitabine (CAPOXI) following a relapse, and this continued for six months (six cycles), when the treatment was interrupted because of the disease’s progression and hematological and gastrointestinal toxicity. Following an assessment of the K-ras, diagnosed as wild type, the patient was excluded from second-line chemotherapy treatment because of decompensated cirrhosis and the persistence of thrombocytopenia and leukopenia. The patient was put forward for biological treatment with an anti-EGFR monoclonal antibody (Panitumumab). Panitumumab was administered at a dosage of 6 mg/kg every 2 weeks for 17 months;the treatment was well tolerated, despite the cirrhosis, and the main toxicity was the skin rash. Conclusion: In patients with severe comorbidities such as cirrhosis of the liver and K-ras wild-type carcinomas, therapy with a monoclonal antibody such as Panitumumab is a treatment that is well tolerated, with few serious toxic side-effects;it also offers advantages in terms of survival and clinical benefits.展开更多
BACKGROUND Gastrointestinal stromal tumors(GISTs) associated with neurofibromatosis are uncommon compared to their gastrointestinal counterparts. Patients with neurofibromatosis type 1(NF-1) have an increased risk of ...BACKGROUND Gastrointestinal stromal tumors(GISTs) associated with neurofibromatosis are uncommon compared to their gastrointestinal counterparts. Patients with neurofibromatosis type 1(NF-1) have an increased risk of developing gastrointestinal tumors, including rare types such as GIST.CASE SUMMARY A 60-year-old male Chinese patient was diagnosed with NF-1 10 years ago and presented with upper abdominal discomfort and black stools. Endoscopic ultrasonography and an enhanced abdominal computed tomography scan revealed a mass located 4 cm from the muscular layer of the descending duodenum. A 59-year-old Chinese woman who was diagnosed with NF-1 25 years ago presented with sudden unconsciousness and black stools. Multiple masses in the duodenum were noted by echogastroscopy and an enhanced abdominal computed tomography scan. Both patients presented with cutaneous neurofibromas. The histologic examination of tumors from both patients revealed spindle cells and low mitotic activity. Immunohistochemically, the tumor cells showed strong positivity for KIT(CD117), DOG-1, CD34, and Dehydrogenase Complex Subunit B, and negativity for SMA, desmin, S-100, and β-catenin. None of the six tumors from two patients had KIT exon 9, 11, 13, or 17 or platelet-derived growth factor receptor α exon 12 or 18 mutation, which is a typical finding for sporadic GISTs. None of the six tumors from the two patients had a BRAFV600 E mutation. The patients were alive and well during the follow-up period(range:0.6-5 yr).CONCLUSION There have been only a few previous reports of GISTs associated with NF-1.Although GISTs associated with NF-1 have morphologic and immunohistochemical similarities with GISTs, the pathogenesis, incidence,genetic background, and prognosis are not completely known. A medical history of NF-1 in a patient who has gastrointestinal bleeding or anemia and an intraabdominal mass with nonspecific computed tomography features may help in diagnosing GIST by virtue of the well-known association of these two entities.Molecular genetic studies of cases indicated that GISTs in NF-1 patients have a different pathogenesis than sporadic GISTs.展开更多
Background： Myocardial infarction （MI） is a major disease burden. Wild-type p53-induced phosphatase 1 （Wipl） has been studied extensively in the context of cancer and the regulation of different types of stem cel...Background： Myocardial infarction （MI） is a major disease burden. Wild-type p53-induced phosphatase 1 （Wipl） has been studied extensively in the context of cancer and the regulation of different types of stem cells, but the role of Wipl in cardiac adaptation to M I is unknown. We investigated the significance of Wipl in a mouse model of MI. Methods： The study began in June 2014 and was completed in July 2016. We compared Wipl-knockout （Wipl-KO） mice and wild-type （WT） mice to deternline changes in cardiac function and survival in response to MI. The heart weight/body weight （HW/BW） ratio and cardiac function were measured before MI. Mouse MI was established by ligating the left anterior descending （LAD） coronary artery under 1.5% isoflurane anesthesia. After M1, survival of the mice was observed for 4 weeks. Cardiac function was examined by echocardiography. The HW/BW ratio was analyzed, and cardiac hypertrophy was measured by wheat germ agglutinin staining. Hematoxylin and eosin （H＆E） staining was used to determine the infarct size. Gene expression of interleukin-6 （IL-6）, turnor necrosis factor-α （TNF-α）, and interleukin-1β （IL-1β） was assessed by quantitative real-time polymerase chain reaction （qPCR）, and the levels of signal transducers and activators of transcription 3 （stat3） and phosphor-stat3 （p-stat3） were also analyzed by Western blotting. Kaplan-Meier survival analysis, log-rank test, unpaired l-test, and one-way analysis of variance （ANOVA） were used for statistical analyses. Results： Wipl-KO mice had a marginally increased HW/BW ratio and slightly impaired cardiac fiinction before LAD ligation. Alter MI, Wipl-deficient mice exhibited increased mortality （57.14% vs. 29.17%; n = 24 [WT], n - 35 [WipI-KO], P 〈 0.05）, increased cardiac hypertrophy （HW/BW ratio： 7 days： 7.25±0.36 vs. 5.84 ± 0.18, n cross-sectional area： 7 days： 311.80 ± 8.29 vs. 268.90 ± 11.15, n P 〉 0.05）, and reduced cardiac function （ejection fraction： 7 days 10, p〈 0.01, and 4 weeks： 6.05± 0.17 vs. 5.87 ±0.24, n= 10, P〉0.05; P 〈 0.05, and 4 weeks： 308.80 ± 11.26 vs. 317.00 ±13.55, n = 6 29.37± 1.38 vs. 34.72 ± 1.81, P 〈 0.05, and 4 weeks： 19.06 ± 2.07 vs 26.37 ± 2.95, P〈 0.05; fractional shortening： 7 days： 13.72 ± 0.71 vs. 16.50 ± 0.94, P〈 0.05, and 4 weeks： 8.79 ±1.00 vs. 12.48 ±1.48, P 〈 0.05; n = l0 [WT], n = 15 [Wipl-KO]）. H＆E staining revealed a larger infarct size in Wipl-KO mice than in WT mice （34.79% ± 2.44% vs. 19.55% ± 1.48%, n = 6, P 〈 0.01 ）. The expression oflL-6 and p-stat3 was downregulated in Wipl-KO mice （IL-6：1.71 ± 0.27 vs. 4.46 ± 0.79, n = 6, P 〈 0.01 ; and p-stat3/stat3：1.15 ±0.15 vs. 1.97 ± 0.23, n = 6, P 〈 0.05）. Conclusion： The results suggest that Wipl could protect the heart from MI-induced ischemic injury.展开更多
Epidermal growth factor receptor(EGFR)tyrosine kinase inhibitors(TKI),such as Erlotinib,have demonstrated remarkable efficacy in the treatment of non-small cell lung cancer(NSCLC)patients with mutated EGFR.However,the...Epidermal growth factor receptor(EGFR)tyrosine kinase inhibitors(TKI),such as Erlotinib,have demonstrated remarkable efficacy in the treatment of non-small cell lung cancer(NSCLC)patients with mutated EGFR.However,the efficacy of EGFR-TKIs in wild-type(wt)EGFR tumours has been shown to be marginal.Methods that can sensitize Erlotinib to EGFR wild-type NSCLC remain rare.Herein,we developed a multifunctional superparamagnetic nanotheranostic agent as a novel strategy to potentiate Erlotinib to EGFR-wt NSCLCs.Our results demonstrate that the nanoparticles can co-escort Erlotinib and a vascular epithermal growth factor(VEGF)inhibitor,Bevacizumab(Bev),to EGFR-wt tumours.The nanotheranostic agent exhibits remarkable effects as an inhibitor of EGFR-wt tumour growth.Moreover,Bev normalizes the tumour embedded vessels,further promoting the therapeutic efficacy of Erlotinib.In addition,the tumour engagement of the nanoparticles and the vascular normalization could be tracked by magnetic resonance imaging(MRI).Collectively,our study,for the first time,demonstrated that elaborated nanoparticles could be employed as a robust tool to potentiate Erlotinib to EGFR-wt NSCLC,paving the way for imaging-guided nanotheranostics for refractory NSCLCs expressing EGFR wild-type genes.展开更多
This editorial discusses Wang et al's article on familial gastrointestinal stromal tumors(GISTs).We read with great interest this article concerning the diagnosis,treatment,and post-treatment management of patient...This editorial discusses Wang et al's article on familial gastrointestinal stromal tumors(GISTs).We read with great interest this article concerning the diagnosis,treatment,and post-treatment management of patients with familial GISTs.The actual incidence of GISTs may be underestimated due to diagnostic limitations and the long-term low-risk behavior of some GISTs.The molecular landscape of GISTs is primarily driven by mutations in the KIT and platelet-derived growth factor receptor alpha(PDGFRA)genes.A subset of GISTs without these mutations known as wild-type GISTs,may harbor other rare mutations,impacting their response to targeted therapies.Clinically,patients with GISTs present with nonspecific symptoms,often leading to delayed diagnosis.Genetic predispositions in familial GISTs provide insights into the genetic architecture and extragastrointestinal manifestations of GISTs.Management has evolved from surgical interventions to molecular-based therapies using tyrosine kinase inhibitors.The management of GISTs,especially in familial cases,requires a multidisciplinary approach.Cases of different gene mutations were reported in the same family,suggesting that incorporating genetic testing into routine clinical practice is crucial for the early identification of high-risk individuals and the implementation of tailored surveillance programs.展开更多
文摘BACKGROUND The combination of anti-epidermal growth factor receptor(EGFR)therapy and chemotherapy is currently a preferred first-line treatment for patients with unre-sectable,RAS and BRAF wild-type,left-sided metastatic colorectal cancer(mCRC).Several studies have also demonstrated the benefit of anti-EGFR therapy in sub-sequent line settings for this patient population.However,direct evidence com-paring the effectiveness of frontline vs subsequent anti-EGFR therapy remains limited,leaving a crucial gap in guiding optimal treatment strategies.AIM To compare overall survival(OS)between frontline and subsequent anti-EGFR treatment in patients with unresectable,RAS and BRAF wild-type,left-sided mCRC.METHODS We retrospectively reviewed the medical records of mCRC patients treated at The King Chulalongkorn Memorial Hospital and Songklanagarind Hospital,Thailand,between January 2013 and April 2023.Patients were classified into two groups based on the sequence of their anti-EGFR treatment.The primary endpoint was OS.RESULTS Among 222 patients with a median follow-up of 29 months,no significant difference in OS was observed between the frontline and subsequent-line groups(HR 1.03,95%CI:0.73-1.46,P=0.878).The median OS was 35.53 months(95%CI:26.59-44.47)for the frontline group and 31.60 months(95%CI:27.83-35.37)for the subsequent-line group.In the subsequent-line group,71 patients(32.4%)who ultimately never received anti-EGFR therapy had a significantly worse median OS of 19.70 months(95%CI:12.87-26.53).CONCLUSION Frontline and subsequent-line anti-EGFR treatments provide comparable OS in unresectable,RAS/BRAF wild-type,left-sided mCRC patients,but early exposure is vital for those unlikely to receive subsequent therapy.
基金a grant from the National Natural Sciences Foundation of China (No. 30571950)National Key Basic Research Program Foundation (N0.2002CB513107).
文摘The reversing effect of wild-type PTEN gene on resistance of C 13K cells to cisplatin and its inhibitory effect on the phosphorylation of protein kinase B （AKT） were studied. The expression of PTEN mRNA and protein in OV2008 cells and C13K cells were semi-quantitatively detected by using RT-PCR and Western blotting. Recombinant eukaryotic expression plasmid containing human wild-type PTEN gene was transfected into C13K cells by lipofectamine2000. The expression of PTEN mRNA was monitored by RT-PCR and the expression of PTEN, Akt, p-Akt protein were ana- lyzed by Western blotting in PTEN-transfected and non-transfected C13K cells. Proliferation and chemosensitivity of cells to DDP were measured by MTT, and cell apoptosis was detected by flow cytometry after treatment with cisplatin. The expression of PTEN mRNA and protein in OV2008 cells were significantly higher than those in C13K cells. After transfection with PTEN gene for 48 h, the expression of PTEN mRNA and protein in C 13K cells were 2.04 ± 0.10, 0.94± 0.04 respectively and the expression of p-Akt protein （ 0.94± 0.07） was lower than those in control groups （1.68 ±0.14, 1.66± 0.10） （P〈 0.05）. The IC50 of DDP to C 13 K cells transfected with PTEN （7.2± 0.3 la mol/L） was obviously lower than those of empty-vector transfected cells and non-transfected cells （12.7±0.4 lamol/1, 13.0±0.3 lamol/L） （P〈0.05）. The apopototis ratio of wild-type PTEN-transfected, empty vector transfected and non-transfected C13K cells were （41.65___0.87）%, （18.61 ±0.70）% and （15.28±0.80）% respectively, and the difference was statistically significant （P〈0.05）. PTEN gene plays an important role in ovarian cancer multidrug resistance. Transfection of PTEN could increase the expression of PTEN and restore drug sensitivity to cisplatin in human ovarian cancer cell line C 13K with multidrug-resistance by decreasing the expression of p-Akt.
基金The PhD Foundation of Education Ministry, China, No. 20050226002the Doctor Foundation of Harbin Medical University+1 种基金 The Youth Foundation of Heilongjiang Province, No. QC06C061The Foundation of Education Department, Heilongjiang Province, No. 11521089
文摘AIM:To construct eukaryotic expression plasmids of full-length Hepatitis B Virus(HBV) genotype C genome,which contain lamivudine-resistant mutants(YIDD,YVDD) or wild-type strain(YMDD) ,and to observe the expression of HBV DNA and antigens [hepatitis B surface antigen(HBsAg) and hepatitis B e antigen(HBeAg) ] of the recombinant plasmids in HepG2 cells. METHODS:Three HBV full-length genomes were amplified from the plasmids pMD18T-HBV/YIDD,pMD18T-HBV/YVDD and pMD18T-HBV/YMDD,using PCR. Three recombinant plasmids were generated by inserting each of the PCR products into the eukaryotic expression vector pcDNA3.1(+) ,between the EcoRI and HindⅢ sites. After being characterized by restriction endonuclease digestion,and DNA sequence analysis,the recombinant plasmids were transfected into HepG2 cells. At 48 and 72 h post-transfection,the levels of intracellular viral DNA replication were detected by real-time PCR,and the expression of HBsAg and HBeAg in the cell culture supernatant was determined by ELISA. RESULTS:Restriction endonuclease digestion and DNA sequence analysis confirmed that the threerecombinant plasmids were correctly constructed. After transfecting the plasmids into HepG2 cells,high levels of intracellular viral DNA replication were observed,and HBsAg and HBeAg were secreted into the cell culture supernatant. CONCLUSION:Eukaryotic expression plasmids pcDNA3.1(+) -HBV/YIDD,pcDNA3.1(+) -HBV/YVDD or pcDNA3.1(+) -HBV/YMDD,which contained HBV genotype C full-length genome,were successfully constructed. After transfection into HepG2 cells,the recombinant plasmids efficiently expressed HBV DNA,HBsAg and HBeAg. Our results provide an experimental basis for the further study of HBV lamivudine-resistant mutants.
基金Supported by The National Natural Science Foundation of China, No.30700809 and No.30972876
文摘AIM: To clarify the biological role of stem cell factor (SCF)-mediated wild-type KIT receptor activation in gastrointestinal stromal tumor (GIST) growth. METHODS: The co-expression of wild-type KIT receptor and SCF was evaluated in 51 GIST samples using mutation analysis and immunohistochemistry, and the results were correlated with clinicopathological param- eters, including the mitotic count, proliferative index (Ki-67 immunohistochemical staining), mitotic index (phospho-histone H3 immunohistochemical staining) and apoptotic index (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling). Using primary cultured GIST cells, the effect of SCF-mediated wild-type KIT receptor activation was determined by western blotting, methyl thiazolyl tetrazolium (MTT), and apoptosis assays. RESULTS: We found that wild-type KIT receptor and SCF protein were expressed in 100% and 76.5% of the 51 GIST samples, respectively, and the co-expression of wild-type KIT receptor and SCF was associated with known indicators of poor prognosis, including larger tumor size (P = 0.0118), higher mitotic count (P = 0.0058), higher proliferative index (P = 0.0012), higher mitotic index (P = 0.0282), lower apoptosis index (P = 0.0484), and increased National Institutes of Health risk level (P = 0.0012). We also found that the introduction of exogenous SCF potently increased KIT kinase activity, stimulated cell proliferation (P < 0.01) and inhibited apoptosis (P < 0.01) induced by serum starvation, while a KIT immunoblocking antibody suppressed proliferation (P = 0.01) and promoted apoptosis (P < 0.01) in cultured GIST cells. CONCLUSION: SCF-mediated wild-type KIT receptor activation plays an important role in GIST cell growth. The inhibition of SCF-mediated wild-type KIT receptor activation may prove to be particularly important for GIST therapy.
文摘The goal of this study was to determine whether mutation of the Mn-binding site of wild-type recombinant Phlebia radiata manganese peroxidase 3 affected the pH-dependence kinetic parameters. pH range investigated was 2.5 – 12.0. The catalytic efficiency of the mutant enzymes at high and low pH in comparison to the wild-type was investigated using standard rPr-MnP3 protocol. Wild-type recombinant Phlebia radiata MnP3 enzyme showed optimal activity with Mn (II) as substrate at pH 5.0 and remained moderately active (approximately 40%) in the pH range of 6.0 - 9.0. The rPr-MnP3 mutants’ maximum activity ranged between 5.5 and 8.0. Wild-type and mutants rPr-MnP3 enzymes exhibited a similar pH profile with optimum pH of 3.0 for ABTS oxidation. Mutation has severely decreased the catalytic efficiency for Mn (II) oxidation at pH 5.0. The rPr-MnP3 enzymes showed enhanced affinity for Mn (II) at alkaline pH and a more alkaline range for catalysis than ever reported for any Manganese Peroxidase. This study reveals that at higher pH, rPr-MnP3 can function with alternative ligands in the Mn (II) site and does not have an absolutely obligate requirement for an all carboxylate ligand set. These results further strongly confirm that Mn<sup>2+</sup> binding site is the only productive catalytic site for Mn (II) oxidation.
文摘BACKGROUND Wild-type transthyretin amyloidosis(ATTRwt)is the most common form of transthyretin amyloid cardiomyopathy,occurring mostly over age of 60 years(mean age of 80 years).Mean survival without treatment is 3.6 years,making early detection imperative.We report an unusual case of a 58-year-old patient with ATTRwt cardiomyopathy requiring heart transplantation.CASE SUMMARY A 58-year-old male presented with progressive fatigue,shortness of breath,weight gain,leg swelling,orthopnoea,and paroxysmal nocturnal dyspnoea for several months.Approximately ten months before this clinical presentation,the patient had first received a diagnosis of heart failure with reduced ejection fraction(EF)of 15% to 20%.The patient was started on appropriate guidelinedirected medical therapy with only mild improvement in his EF.Upon further investigation,echocardiogram,technetium pyrophosphate scan(Tc PYP),and cardiac magnetic resonance imaging(cMRI)suggested a diagnosis of amyloidosis,and ATTRwt was subsequently confirmed with native heart tissue biopsy,congo red staining,liquid chromatography-tandem mass spectrometry,and genetic testing.The patient was successfully treated with heart transplantation and is doing well post-transplant.CONCLUSION Wild-type ATTR amyloidosis should be kept on differentials in all patients(even less than 60 years old)with non-ischemic cardiomyopathy,especially in the setting of increased ventricular wall thickness and other classic echocardiogram,cMRI,and Tc PYP findings.Early diagnosis and management can be consequential in improving patient outcomes.
文摘K-ras wild-type carcinoma is a tumour that is sensitive to treatment with anti-cancer and anti-EGFR drugs: the combination of Cetuximab and Panitumumab with chemotherapy (Cetuximab) or as a single therapy (Panitumumab). Case Report: The clinical case presented here refers to a 68-year-old patient who had been diagnosed with adenocarcinoma of the recto sigmoid with pelvic recurrence three years after surgery. The patient had a severe co-morbidity: correlated B-type liver cirrhosis. First-line chemotherapy was begun with Oxaliplatin plus Capecitabine (CAPOXI) following a relapse, and this continued for six months (six cycles), when the treatment was interrupted because of the disease’s progression and hematological and gastrointestinal toxicity. Following an assessment of the K-ras, diagnosed as wild type, the patient was excluded from second-line chemotherapy treatment because of decompensated cirrhosis and the persistence of thrombocytopenia and leukopenia. The patient was put forward for biological treatment with an anti-EGFR monoclonal antibody (Panitumumab). Panitumumab was administered at a dosage of 6 mg/kg every 2 weeks for 17 months;the treatment was well tolerated, despite the cirrhosis, and the main toxicity was the skin rash. Conclusion: In patients with severe comorbidities such as cirrhosis of the liver and K-ras wild-type carcinomas, therapy with a monoclonal antibody such as Panitumumab is a treatment that is well tolerated, with few serious toxic side-effects;it also offers advantages in terms of survival and clinical benefits.
基金Supported by National Natural Science Foundation of China,No.81601692Program of Liaoning Province Department of Education,No.LK2016002
文摘BACKGROUND Gastrointestinal stromal tumors(GISTs) associated with neurofibromatosis are uncommon compared to their gastrointestinal counterparts. Patients with neurofibromatosis type 1(NF-1) have an increased risk of developing gastrointestinal tumors, including rare types such as GIST.CASE SUMMARY A 60-year-old male Chinese patient was diagnosed with NF-1 10 years ago and presented with upper abdominal discomfort and black stools. Endoscopic ultrasonography and an enhanced abdominal computed tomography scan revealed a mass located 4 cm from the muscular layer of the descending duodenum. A 59-year-old Chinese woman who was diagnosed with NF-1 25 years ago presented with sudden unconsciousness and black stools. Multiple masses in the duodenum were noted by echogastroscopy and an enhanced abdominal computed tomography scan. Both patients presented with cutaneous neurofibromas. The histologic examination of tumors from both patients revealed spindle cells and low mitotic activity. Immunohistochemically, the tumor cells showed strong positivity for KIT(CD117), DOG-1, CD34, and Dehydrogenase Complex Subunit B, and negativity for SMA, desmin, S-100, and β-catenin. None of the six tumors from two patients had KIT exon 9, 11, 13, or 17 or platelet-derived growth factor receptor α exon 12 or 18 mutation, which is a typical finding for sporadic GISTs. None of the six tumors from the two patients had a BRAFV600 E mutation. The patients were alive and well during the follow-up period(range:0.6-5 yr).CONCLUSION There have been only a few previous reports of GISTs associated with NF-1.Although GISTs associated with NF-1 have morphologic and immunohistochemical similarities with GISTs, the pathogenesis, incidence,genetic background, and prognosis are not completely known. A medical history of NF-1 in a patient who has gastrointestinal bleeding or anemia and an intraabdominal mass with nonspecific computed tomography features may help in diagnosing GIST by virtue of the well-known association of these two entities.Molecular genetic studies of cases indicated that GISTs in NF-1 patients have a different pathogenesis than sporadic GISTs.
文摘Background： Myocardial infarction （MI） is a major disease burden. Wild-type p53-induced phosphatase 1 （Wipl） has been studied extensively in the context of cancer and the regulation of different types of stem cells, but the role of Wipl in cardiac adaptation to M I is unknown. We investigated the significance of Wipl in a mouse model of MI. Methods： The study began in June 2014 and was completed in July 2016. We compared Wipl-knockout （Wipl-KO） mice and wild-type （WT） mice to deternline changes in cardiac function and survival in response to MI. The heart weight/body weight （HW/BW） ratio and cardiac function were measured before MI. Mouse MI was established by ligating the left anterior descending （LAD） coronary artery under 1.5% isoflurane anesthesia. After M1, survival of the mice was observed for 4 weeks. Cardiac function was examined by echocardiography. The HW/BW ratio was analyzed, and cardiac hypertrophy was measured by wheat germ agglutinin staining. Hematoxylin and eosin （H＆E） staining was used to determine the infarct size. Gene expression of interleukin-6 （IL-6）, turnor necrosis factor-α （TNF-α）, and interleukin-1β （IL-1β） was assessed by quantitative real-time polymerase chain reaction （qPCR）, and the levels of signal transducers and activators of transcription 3 （stat3） and phosphor-stat3 （p-stat3） were also analyzed by Western blotting. Kaplan-Meier survival analysis, log-rank test, unpaired l-test, and one-way analysis of variance （ANOVA） were used for statistical analyses. Results： Wipl-KO mice had a marginally increased HW/BW ratio and slightly impaired cardiac fiinction before LAD ligation. Alter MI, Wipl-deficient mice exhibited increased mortality （57.14% vs. 29.17%; n = 24 [WT], n - 35 [WipI-KO], P 〈 0.05）, increased cardiac hypertrophy （HW/BW ratio： 7 days： 7.25±0.36 vs. 5.84 ± 0.18, n cross-sectional area： 7 days： 311.80 ± 8.29 vs. 268.90 ± 11.15, n P 〉 0.05）, and reduced cardiac function （ejection fraction： 7 days 10, p〈 0.01, and 4 weeks： 6.05± 0.17 vs. 5.87 ±0.24, n= 10, P〉0.05; P 〈 0.05, and 4 weeks： 308.80 ± 11.26 vs. 317.00 ±13.55, n = 6 29.37± 1.38 vs. 34.72 ± 1.81, P 〈 0.05, and 4 weeks： 19.06 ± 2.07 vs 26.37 ± 2.95, P〈 0.05; fractional shortening： 7 days： 13.72 ± 0.71 vs. 16.50 ± 0.94, P〈 0.05, and 4 weeks： 8.79 ±1.00 vs. 12.48 ±1.48, P 〈 0.05; n = l0 [WT], n = 15 [Wipl-KO]）. H＆E staining revealed a larger infarct size in Wipl-KO mice than in WT mice （34.79% ± 2.44% vs. 19.55% ± 1.48%, n = 6, P 〈 0.01 ）. The expression oflL-6 and p-stat3 was downregulated in Wipl-KO mice （IL-6：1.71 ± 0.27 vs. 4.46 ± 0.79, n = 6, P 〈 0.01 ; and p-stat3/stat3：1.15 ±0.15 vs. 1.97 ± 0.23, n = 6, P 〈 0.05）. Conclusion： The results suggest that Wipl could protect the heart from MI-induced ischemic injury.
基金This study was supported partly by grants from the Natural Science Foundation of China(81771973,81971672 and 82102005)Key Program of the Natural Science Foundation of Guangdong Province(2018B0303110011)+3 种基金Guangzhou Key Laboratory of Molecular and Functional Imaging for Clinical Translation(201905010003)Fundamental Research Funds for the Central Universities(21620308 and 21620101)JSPS KAKENHI grant Nos.21H02873,21K07659,and 20H03635the AMED Moonshot Research and Development Program(Grant No 21zf0127003h001).
文摘Epidermal growth factor receptor(EGFR)tyrosine kinase inhibitors(TKI),such as Erlotinib,have demonstrated remarkable efficacy in the treatment of non-small cell lung cancer(NSCLC)patients with mutated EGFR.However,the efficacy of EGFR-TKIs in wild-type(wt)EGFR tumours has been shown to be marginal.Methods that can sensitize Erlotinib to EGFR wild-type NSCLC remain rare.Herein,we developed a multifunctional superparamagnetic nanotheranostic agent as a novel strategy to potentiate Erlotinib to EGFR-wt NSCLCs.Our results demonstrate that the nanoparticles can co-escort Erlotinib and a vascular epithermal growth factor(VEGF)inhibitor,Bevacizumab(Bev),to EGFR-wt tumours.The nanotheranostic agent exhibits remarkable effects as an inhibitor of EGFR-wt tumour growth.Moreover,Bev normalizes the tumour embedded vessels,further promoting the therapeutic efficacy of Erlotinib.In addition,the tumour engagement of the nanoparticles and the vascular normalization could be tracked by magnetic resonance imaging(MRI).Collectively,our study,for the first time,demonstrated that elaborated nanoparticles could be employed as a robust tool to potentiate Erlotinib to EGFR-wt NSCLC,paving the way for imaging-guided nanotheranostics for refractory NSCLCs expressing EGFR wild-type genes.
基金National Natural Science Foundation of China,No.82370569Basic and Applied Basic Research Foundation of Guangdong Province,No.2022A1515012647the Key Program for Science and Technology Projects of Social Development in Zhuhai,No.2220004000249(to Li XF).
文摘This editorial discusses Wang et al's article on familial gastrointestinal stromal tumors(GISTs).We read with great interest this article concerning the diagnosis,treatment,and post-treatment management of patients with familial GISTs.The actual incidence of GISTs may be underestimated due to diagnostic limitations and the long-term low-risk behavior of some GISTs.The molecular landscape of GISTs is primarily driven by mutations in the KIT and platelet-derived growth factor receptor alpha(PDGFRA)genes.A subset of GISTs without these mutations known as wild-type GISTs,may harbor other rare mutations,impacting their response to targeted therapies.Clinically,patients with GISTs present with nonspecific symptoms,often leading to delayed diagnosis.Genetic predispositions in familial GISTs provide insights into the genetic architecture and extragastrointestinal manifestations of GISTs.Management has evolved from surgical interventions to molecular-based therapies using tyrosine kinase inhibitors.The management of GISTs,especially in familial cases,requires a multidisciplinary approach.Cases of different gene mutations were reported in the same family,suggesting that incorporating genetic testing into routine clinical practice is crucial for the early identification of high-risk individuals and the implementation of tailored surveillance programs.
