Human bone marrow mesenchymal stem cell-derived exosomes loaded with gemcitabine inhibit pancreatic cancer cell proliferation by enhancing apoptosis

BACKGROUND Pancreatic cancer remains one of the most lethal malignancies,and has limited effective treatment.Gemcitabine(GEM),a chemotherapeutic agent,is commonly used for clinical treatment of pancreatic cancer,but it has characteristics of low drug delivery efficiency and significant side effects.The study tested the hypothesis that human bone marrow mesenchymal stem cell(MSC)-derived exosomes loaded with GEM(Exo-GEM)would have a higher cytotoxicity against human pancreatic cancer cells by enhancing their apoptosis.AIM To investigate the cytotoxicity of MSC-derived Exo-GEM against pancreatic cancer cells in vitro.METHODS Exosomes were isolated from MSCs and characterized by transmission electron microscopy and nanoparticle tracking analysis.Exo-GEM through electroporation,sonication,or incubation,and the loading efficiency was evaluated.The cytotoxicity of Exo-GEM or GEM alone against human pancreatic cancer Panc-1 and MiaPaca-2 cells was assessed by MTT and flow cytometry assays.RESULTS The isolated exosomes had an average size of 76.7 nm.The encapsulation efficacy and loading efficiency of GEM by electroporation and sonication were similar and significantly better than incubation.The cytotoxicity of Exo-GEM against pancreatic cancer cells was stronger than free GEM and treatment with 0.02μM Exo-GEM significantly reduced the viability of both Panc-1 and MiaPaca-2 cells.Moreover,Exo-GEM enhanced the frequency of GEMinduced apoptosis in both cell lines.CONCLUSION Human bone marrow MSC-derived Exo-GEM have a potent cytotoxicity against human pancreatic cancer cells by enhancing their apoptosis,offering a promising drug delivery system for improving therapeutic outcomes.

Hepatic arterial infusion of gemcitabine-oxaliplatin in a large metastasis from colon cancer

Hepatic arterial infusion (HAI) of chemotherapy can be performed in cases of liver-confined metastatic disease,resulting in increased local drug concentrations.Here we report the case of a 61-year-old man who presented with an isolated large unresectable liver metastasis of colon cancer after failure of surgery and multiple administration of systemic chemotherapy.The patient was treated with a combination of gemcitabine and oxaliplatin using HAI.The tolerance was excellent and a radiological complete response was obtained after 8 cycles of HAI.The rationale for the use of gemcitabine and oxaliplatin as well as that for the combination of the 2 drugs is discussed in this paper.HAI of gemcitabine-oxaliplatin should be evaluated in further clinical trials.

Clinical efficacy of gemcitabine and cisplatin-based transcatheter arterial chemoembolization combined with radiotherapy in hilar cholangiocarcinoma

BACKGROUND Radical surgical resection is regarded as the best treatment for hepatic hilar cholangiocarcinoma. However, 60%-70% of patients have lost the chance of surgery at the time of diagnosis. Simple biliary stent or drainage tube placement may fail in a short time due to tumor invasion or overgrowth, bile accumulation, or biofilm formation. Effective palliative treatments to extend the effective drainage time are of great significance for improving the quality of life of patients and changing the prognosis of patients. AIM To investigate the clinical efficacy of gemcitabine and cisplatin-based transcatheter arterial chemoembolization (TACE) combined with radiotherapy in hilar cholangiocarcinoma.METHODS A retrospective analysis was conducted on patients clinically diagnosed with hilar cholangiocarcinoma from June 2014 to January 2017 at the Liaoning Provincial Cancer Hospital. Patients were evaluated by specialists, and those who were not suitable for surgery or unwilling to undergo surgery and met the inclusion criteria were included in the study. There were a total of 72 patients (34 males and 38 females) with an average age of 59.9 years (range, 40-72 years). According to percutaneous transhepatic biliary angiography and the patients’ wishes, stent implantation or biliary drainage tube implantation was used to relieve biliary obstruction. The patients were divided into either a control group or a combined treatment group according to their follow-up treatment. The control group consisted of a total of 35 patients who received simple biliary drainage tube placement and biliary stent implantation (7 patients with bilateral stents and 6 with a unilateral stent) and 22 patients receiving biliary drainage tube placement alone. The combined treatment group received TACE and extracorporeal radiotherapy after biliary drainage or biliary stent implantation and consisted of a total of 37 patients, including 21 patients receiving combined treatment after biliary stent placement (14 patients with bilateral stents and 7 with a unilateral stent) and 16 undergoing combined therapy after implanting the biliary drainage tube. In the combination treatment group, the TACE chemotherapy regimen employed gemcitabine and cisplatin, and the embolic agent was iodized oil. A particular dose was determined according to the patient's body surface area and the tumor staining indicated by DSA. In vitro radiotherapy was performed with intensity-modulated radiotherapy or threedimensional conformal radiotherapy at an average dose of 48.3 Gy. Both groups were followed from stent implantation or drainage tube implantation until the patient quitted or died. The median length of follow-up observation was 13 mo. The differences in overall survival time and the effect of different jaundice reducing methods (single stent, double stent, or biliary drainage) on the patency time and survival time of biliary stents were compared between the two groups;the related factors affecting overall survival time were analyzed. RESULTS The median survival time of the control group was 10.5 mo;the median survival time of patients with biliary stent implantation and those with percutaneous biliary drainage was 9.6 mo and 11.4 mo, respectively, and there was no statistically significant difference between them. The median survival time of the combined treatment group was 20.0 mo, which was significantly higher than that of the control group (P < 0.05). Among patients in the combined treatment group, the median survival time of patients who underwent biliary stent implantation and those who accepted percutaneous biliary drainage before the combination therapy was 19.5 mo and 20.1 mo, respectively, and there was no significant difference between them. In the combination treatment group, the mean time of median stent patency was 15.6 mo, which was significantly higher than that of the control group (7.0 mo;P < 0.05). The independent factors affecting survival time included age, whether to receive combination therapy, percutaneous biliary drainage tube implantation, and Bismuth-Corlette classification as type IV. CONCLUSION Gemcitabine and cisplatin-based TACE combined with radiotherapy can prolong the survival of patients with hilar cholangiocarcinoma. Independent predictors of survival include selection of combination therapy, Bismuth-Corlette classification as type IV, selection of percutaneous biliary drainage tube implantation, and age.

Molecular predictors of gemcitabine response in pancreatic cancer

Gemcitabine is one of the most used anti-neoplastic drugs with documented activity in almost all major localizations of cancer.In pancreatic cancer treatment,gemcitabine occupies a prominent place as a first line chemotherapy,partly because of the paucity of other efficacious chemotherapy options.In fact,only a minority of pancreatic cancer patients display a response or even stability of disease with the drug.There are currently no clinically applicable means of predicting which patient will derive a clinical benefit from gemcitabine although several proposed markers have been studied. These markers are proteins involved in drug up-take,activation and catabolism or proteins that define the ability of the cell to undergo apoptosis in response to the drug.Several of these markers are reviewed in this paper.We also briefly discuss the possible role of stem cells in drug resistance to gemcitabine.

Adjuvant Chemotherapy of Gemcitabine plus Carboplatin versus Paclitaxel plus Carboplatin in Patients with Resected Non-Small Cell Lung Cancer

Background: This retrospective study was to evaluate the efficacy and toxicity of gemcitabine plus carboplatin (GC regimen) and paclitaxel plus carboplatin (PC regimen) combination chemotherapy administered as an adjuvant therapy after complete resection of non-small cell lung cancer. Methods: Forty-four patients (GC regimen, n = 29;PC regimen, n = 15) received gemcitabine at a dose of 1000 mg/m2 on days 1 and 8, and carboplatin with the target dose of area under the curve (AUC) of 4 on day 8 every 28 days and paclitaxel at a dose of 70 mg/m2 on days 1, 8 and 15, and carboplatin with the target dose of AUC of 5 on day 1 every 28 days. Results: A total of 130 cycles of the treatment were administered (averaged, 3.1 in GC arm and 2.7 cycles in PC arm). Forty-three patients (97.7%) completed the scheduled cycles. One patient (2.3%) was discontinued due to grade 4 pneumonia. The dose was reduced in 2 patients (4.5%) due to grade 4 thrombocytopenia. Grade 3/4 neutropenia was significantly observed in the PC group (GC: 12/29, 41.4%;PC: 11/15, 73.3%, p = 0.0443). The nonhematological toxicities were mild. Grade 1/2 alanine aminotransferase and aspartate aminotransferase in the GC group was significantly observed higher compared to those of the PC group (GC: 20/29, 69.0%;PC: 4/15, 26.7%, p = 0.0076). Grade 1/2 alopecia was significantly observed in the PC group (GC: 0/25, 0.0%;PC: 13/15, 86.7%, p 0.0001). There was no treatment-related death. The median survival time (MST) of the entire GC group was 784 days, the 3-year overall survival (OS) was 75.9%, and 3-year recurrence-free survival (RFS) was 65.5%. The MST of the entire PC group was 963 days, the 3-year OS was 80.0%, and the 3-year RFS was 60.0%. Conclusion: These results demonstrate that the GC and PC combination chemotherapies are efficacious and feasible regimens, which should be considered as one of the standard therapies for adjuvant therapy.

Simultaneous Dual Selective Targeted Delivery of Two Covalent Gemcitabine Immunochemotherapeutics and Complementary Anti-Neoplastic Potency of [Se]-Methylselenocysteine

The anti-metabolite chemotherapeutic, gemcitabine is relatively effective for a spectrum of neoplastic conditions that include various forms of leukemia and adenocarcinoma/carcinoma. Rapid systemic deamination of gemcitabine accounts for a brief plasma half-life but its sustained administration is often curtailed by sequelae and chemotherapeutic-resistance. A molecular strategy that diminishes these limitations is the molecular design and synthetic production of covalent gemcitabine immunoche-motherapeutics that possess properties of selective “targeted” delivery. The simultaneous dual selective “targeted” delivery of gemcitabine at two separate sites on the external surface membrane of a single cancer cell types represents a therapeutic approach that can increase cytosol chemotherapeutic deposition;prolong chemotherapeutic plasma half-life (reduces administration frequency);minimize innocent exposure of normal tissues and healthy organ systems;and ultimately enhance more rapid and thorough resolution of neoplastic cell populations. Materials and Methods: A light-reactive gemcitabine intermediate synthesized utilizing succinimidyl 4,4-azipentanoate was covalently bound to anti-EGFR or anti-HER2/neu IgG by exposure to UV light (354-nm) resulting in the synthesis of covalent immunoche-motherapeutics, gemcitabine-(C4-amide)-[anti-EGFR] and gemcitabine-(C4-amide)-[anti-HER2/neu]. Cytotoxic anti-neoplastic potency of gemcitabine-(C4-amide)-[anti-EGFR] and gemcitabine-(C4-amide)-[anti-HER2/neu] between?gemcitabine-equivalent concentrations of 10-12 M and 10-6 M was determined utilizing chemotherapeutic-resistant mammary adenocarcinoma (SKRr-3). The organoselenium compound, [Se]-methylselenocysteine was evaluated to determine if it complemented the anti-neoplastic potency of the covalent gemcitabine immunoche-motherapeutics. Results: Gemcitabine-(C4-amide)-[anti-EGFR], gemcitabine-(C4-amide)-[anti-HER2/neu] and the dual simultaneous combination of gemcitabine-(C4-amide)-[anti-EGFR] with gemcitabine-(C4-amide)-[anti-HER2/neu] all had anti-neoplastic cytotoxic potency against mammary adenocarcinoma. Gemcitabine-(C4-amide)-[anti-EGFR] and gemcitabine-(C4-amide)-[anti-HER2/neu] produced progressive increases in anti-neoplastic cytotoxicity that were greatest between gemcitabine-equivalent concentrations of 10-9 M and 10-6 M. Dual simultaneous combinations of gemcitabine-(C4-amide)-[anti-EGFR] with gemcitabine-(C4-amide)-[anti-HER2/neu] produced levels of anti-neoplastic cytotoxicity intermediate between each of the individual covalent gemcitabine immunochemotherapeutics. Total anti-neoplastic cytotoxicity of the dual simultaneous combination of gemcitabine-(C4-amide)-[anti-EGFR] and gemcitabine-(C4-amide)-[anti-HER2/neu] against chemothe-rapeutic-resistant mammary adenocarcinoma (SKBr-3) was substantially higher when formulated with [Se]-methylsele-no-cysteine.

Weekly albumin-bound paclitaxel/cisplatin versus gemcitabine/cisplatin as first-line therapy for patients with advanced non-small-cell lung cancer:A phase II open-label clinical study

Objective: The aim of this trial was to compare both the efficacy and the safety of a weekly nanoparticle albumin-bound paclitaxel(nab-paclitaxel) plus cisplatin vs. gemcitabine plus cisplatin in patients with advanced non-small-cell lung cancer(NSCLC).Methods: A total of 84 participants received either 100 mg/m^2 nab-paclitaxel each week on d 1, 8 and 15 of a 28 day cycle, as well as cisplatin 75 mg/m^2 on d 1 every three weeks(nab-TP arm); or gemcitabine 1,000 mg/m^2 on d 1 and 8, plus cisplatin 75 mg/m^2 on d 1 every three weeks(GP arm). The primary end point was progression-free survival(PFS). The secondary end points were overall response rate(ORR) and overall survival(OS).Results: According to our analysis, the median PFS was 4.8 months for the nab-TP arm vs. 5.2 months for the GP arm(P=0.55). Analysis showed the median OS was 14.6 months for participants who were in the nab-TP arm vs. 15.1 months for those in the GP arm(P=0.94). Besides, nab-TP showed OS advantages over GP in patients harboring epidermal growth factor receptor(EGFR) mutation(26.7 vs. 15.3 months, P=0.046) and patients with a performance status of 0(23.5 vs. 14.7 months, P=0.020). It was found that incidences of drug-related grade 3 or 4 toxicities were comparable between the two treatment arms.Conclusions: Therefore, it can be seen that weekly nab-TP treatment has a similar efficacy and tolerability to GP treatment for patients who are undergoing their first-line treatment for NSCLC. It could be that survival differences among platinum doublets in the context of both EGFR mutation and performance status have the potential to be the basis for our further clinical trials.

Multicenter phase Ⅱ trial of modified FOLFIRINOX in gemcitabine-refractory pancreatic cancer

AIM To evaluate the efficacy and safety of modified FOLFIRINOX as a second-line treatment for gemcitabine(GEM)-refractory unresectable pancreatic cancer(PC).METHODS This study was a prospective, multicenter, one-arm, open-label, phase Ⅱ trial. Patients with unresectable PC, who showed disease progression during GEMbased chemotherapy were enrolled. All patients were administered FOLFIRINOX with reduced irinotecan and oxaliplatin(RIO; irinotecan 120 mg/m^2 and oxaliplatin 60 mg/m^2), which was set according to the phase Ⅰ study of FOLFIRINOX. The objective response rate(ORR), disease control rate(DCR), progressionfree survival(PFS), overall survival(OS), adverse events were evaluated. Additionally, changes in quality of life(QoL) were assessed using a questionnaire on QoL.RESULTS Between August 2015 and May 2016, a total of 48 patients were enrolled. The median follow-up time was 259 d with a median of 8.5 cycles. The ORR and DCR were 18.8% and 62.5%, respectively, including one patient who showed complete remission. The median PFS was 5.8 mo [95% confidence interval(CI): 3.7-7.9] and median OS was 9.0 mo(95%CI: 6.4-11.6). Neutropenia(64.6%) was the most common grade 3-4 adverse event, followed by febrile neutropenia(16.7%). Although 14.6% of patients experienced grade 3 fatigue, most non-hematologic AEs were under grade 2. In the QoL analysis, the global health status score before treatment was not different from the score at the last visit after treatment(45.43 ± 22.88 vs 48.66 ± 24.14, P = 0.548).CONCLUSION FOLFIRINOX with RIO showed acceptable toxicity and promising efficacy for GEM-refractory unresectable PC. However, this treatment requires careful observation of treatment-related hematologic toxicities.

Discussion on gemcitabine combined with targeted drugs in the treatment of pancreatic cancer

Pancreatic cancer is a malignant tumor with poor prognosis.The treatment of pancreatic cancer depends on the tumor stage and type,and includes local treatment(surgery,radiotherapy and ablation intervention)and systemic therapy(chemotherapy,targeted therapy and immunotherapy).We read with great interest the review“Effective combinations of anti-cancer and targeted drugs for pancreatic cancer treatment”published on World J Gastroenterol and intended to share some of our perspectives in pancreatic cancer treatment.This review presents the therapeutic effects of the combination of gemcitabine and targeted drugs,which gives us a deeper insight into the combination treatments for pancreatic cancer.

Efficacy and safety of gemcitabine plus S-1 vs. gemcitabine plus nab-paclitaxel in treatment-na?ve advanced pancreatic ductal adenocarcinoma

Objective:Gemcitabine plus nab-paclitaxel(GnP)is the standard first-line therapy for advanced pancreatic ductal adenocarcinoma(PDAC).S-1,an oral fluoropyrimidine derivative,as compared with gemcitabine,is non-inferior in terms of overall survival(OS)and is associated with lower hematologic toxicity.Accordingly,S-1 is a convenient oral alternative treatment for advanced PDAC.This study was aimed at comparing the efficacy and safety of gemcitabine plus S-1(GS)vs.GnP as first-line chemotherapy for advanced PDAC.Methods:Patients with advanced PDAC who received first-line GS or GnP at the Peking Union Medical College Hospital between March 2011 and November 2022 were evaluated.Results:A total of 300 patients were assessed,of whom 84 received GS and 216 received GnP.The chemotherapy completion rate was higher with GS than GnP(50.0%vs.30.3%,P=0.0028).The objective response rate(ORR)was slightly higher(14.3%vs.9.7%,P=0.35),and the median OS was significantly longer(17.9 months vs.13.3 months,P=0.0078),in the GS group than the GnP group.However,the median progression-free survival(PFS)did not significantly differ between groups.Leukopenia risk was significantly lower in the GS group than the GnP group(14.9%vs.28.1%,P=0.049).Conclusions:As first-line chemotherapy for advanced PDAC,the GS regimen led to a significantly longer OS than the GnP regimen.The PFS,ORR,and incidence of severe adverse events were comparable between the GS and GnP groups.

N-gamboyl Gemcitabine Inhibits Tumor Cells Proliferation and Migration

Gambogic acid(GA) is a natural substance with a good antitumor effect, but it is too lipophilic to be metabolized and excreted, thus accumulating in the body. Gemcitabine(GEM), one of the first-line antitumor drugs, has high hydrophilicity, which greatly shortens its half-life in vivo. We previously reported a compound named N-gamboyl gemcitabine(GAG), derived from the condensation of GEM and GA, whose hydrophilicity is better than GA and stability is better than GEM. Here, the antitumor performance of GAG was investigated for the first time by using several common tumor cell lines as tumor models. The results of in vitro study showed that GAG significantly inhibited the proliferation and migration of the tumor cells. The IC50 values of GAG for the tumor cells were lower than those of GEM and GA. The present study suggests that GAG has a promising potential to be developed into a broad-spectrum antitumor drug.

Effect of α-interferon + gemcitabine combined with infusion chemotherapy on the proliferation and infiltrative growth of advanced bladder cancer

Objective: To study the effect of α-interferon + gemcitabine combined with infusion chemotherapy on the proliferation and infiltrative growth of advanced bladder cancer. Methods: Patients with advanced bladder cancer who accepted bladder infusion chemotherapy in Wuhan Red Cross Hospital between March 2015 and August 2016 were selected and randomly divided into the IFN-α+GEM group and the GEM group who acceptedα-interferon + gemcitabine combined with infusion chemotherapy and single gemcitabine infusion chemotherapy respectively. The contents of bladder cancer markers, cancer cell apoptosis molecules and angiogenesis molecules in urine were detected before treatment and 3 months after treatment. Results: 3 months after treatment, NMP-22, BLCA-4, Apo-A1, HA, CYFRA21-1, ANG, NAC-1, VEGF and bFGF levels in urine of both groups of patients were significantly lower than those before treatment while PTEN, TRAIL, Bim, HSG and p16 levels were significantly higher than those before treatment, and NMP-22, BLCA-4, Apo-A1, HA, CYFRA21-1, ANG, NAC-1, VEGF and bFGF levels in urine of IFN-α+GEM group were significantly lower than those of GEM group while PTEN, TRAIL, Bim, HSG and p16 levels were significantly higher than those of GEM group. Conclusion: α-interferon + gemcitabine combined with infusion chemotherapy can be more effective than single gemcitabine infusion chemotherapy in killing cancer cells and inhibiting the proliferation and infiltrative growth of the cancer cells.

Nuclear PLD1 combined with NPM1 induces gemcitabine resistance through tumorigenic IL7R in pancreatic adenocarcinoma

Objective:Pancreatic ductal adenocarcinoma(PDAC)is a highly malignant gastrointestinal cancer with a 5-year survival rate of only 9%.Of PDAC patients,15%-20%are eligible for radical surgery.Gemcitabine is an important chemotherapeutic agent for patients with PDAC;however,the efficacy of gemcitabine is limited due to resistance.Therefore,reducing gemcitabine resistance is essential for improving survival of patients with PDAC.Identifying the key target that determines gemcitabine resistance in PDAC and reversing gemcitabine resistance using target inhibitors in combination with gemcitabine are crucial steps in the quest to improve survival prognosis in patients with PDAC.Methods:We constructed a human genome-wide CRISPRa/dCas 9 overexpression library in PDAC cell lines to screen key targets of drug resistance based on sgRNA abundance and enrichment.Then,co-IP,ChIP,ChIP-seq,transcriptome sequencing,and qPCR were used to determine the specific mechanism by which phospholipase D1(PLD1)confers resistance to gemcitabine.Results:PLD1 combines with nucleophosmin 1(NPM1)and triggers NPM1 nuclear translocation,where NPM1 acts as a transcription factor to upregulate interleukin 7 receptor(IL7R)expression.Upon interleukin 7(IL-7)binding,IL7R activates the JAK1/STAT5 signaling pathway to increase the expression of the anti-apoptotic protein,BCL-2,and induce gemcitabine resistance.The PLD1 inhibitor,Vu0155069,targets PLD1 to induce apoptosis in gemcitabine-resistant PDAC cells.Conclusions:PLD1 is an enzyme that has a critical role in PDAC-associated gemcitabine resistance through a non-enzymatic interaction with NPM1,further promoting the downstream JAK1/STAT5/Bcl-2 pathway.Inhibiting any of the participants of this pathway can increase gemcitabine sensitivity.

In Frail Elderly Patients, Low-Dose Gemcitabine over 6-Hour Infusion Is Equally Effective and Less Toxic Than the Standard Gemcitabine Protocol for Advanced Pancreatic Adenocarcinoma: A Randomized Phase II Trial

Background:?Treatment of frail elderly patients with pancreatic cancer is still a major problem due to intolerance to standard chemotherapy doses. Aim:?This study aims to compare the low-dose gemcitabine over 6 hours (LD6H) to the standard gemcitabine protocol in terms of clinical benefit, survival, and safety in the frail elderly patients with advanced pancreatic adenocarcinoma. Methods:?Patients enrolled in this trial were randomly assigned by in a 1:1 fashion via closed envelope method to either receive gemcitabine of 1000 mg/m2?over 30-minute infusion on days 1, 8, and 15 of every 4-week cycle (standard protocol arm) or gemcitabine as a weekly low-dose (250 mg/m2) over 6-hour infusion (LD6H arm). Results:?We enrolled eighty-two eligible frail elderly patients with advanced pancreatic cancer. The patients were randomly assigned to receive either standard gemcitabine protocol (40 patients) or low-dose (250 mg/m2) gemcitabine over 6-hour infusion, given weekly (42 patients). There was no significant difference between the standard group and low-dose group as regard of the overall response rate (p = 0.654), the disease control rate (DCR) (p = 0.845), the median progression-free survival (PFS) (p = 0.908) and the overall survival (OS) (p = 0.331). The low-dose regimen had a significantly lower incidence of adverse effects grades 3 or 4 when compared to the standard regimen: (p = 0.024 for fatigue, p = 0.027 for hypotension, p = 0.012 for each anemia as well as thrombocytopenia, and p = 0.006 for neutropenia). Conclusion:?Low-dose gemcitabine over 6-hour infusion is equally effective and less toxic when compared to standard gemcitabine protocol in frail elderly patients with advanced pancreatic adenocarcinoma. So, we recommend the low-dose gemcitabine for frail elderly patients with advanced pancreatic cancer.

Oncogenic ADAM28 induces gemcitabine resistance and predicts a poor prognosis in pancreatic cancer

BACKGROUND Pancreatic cancer is a major cause of cancer-related death,with a 5-year overall survival rate being below 5%.The main causes of poor prognosis in pancreatic cancer include easy metastasis,high recurrence rate,and robust drug resistance.Gemcitabine is a first-line drug for patients with unresectable pancreatic cancer.However,due to drug resistance,the clinical effect is not satisfactory.ADAM28 is reported as a tumor promoter in some cancers,but its role in pancreatic cancer and gemcitabine chemoresistance in pancreatic cancer has not been elucidated.AIM To identify if ADAM28 can act as an important target to reverse the gemcitabine drug resistance in pancreatic cancer.METHODS RNA-sequence analysis was applied to explore the potential targets involved in the gemcitabine of pancreatic cancer.SW1990 pancreatic cancer cells were treated with an increased dose of gemcitabine,and the mRNA levels of ADAM28 were evaluated by RT-PCR.The protein and mRNA levels of ADAM28 were confirmed in the gemcitabine resistant and parallel SW1990 cells.The ADAM28 expression was also assessed in TCGA and GEO databases,and the results were confirmed in the collected tumor and adjacent normal tissues.The overall survival(OS)rate and relapse-free survival(RFS)rate of pancreatic cancer patients with high ADAM28 level and low ADAM28 level in TCGA were evaluated with Kaplan-Meier Plotter.Furthermore,the OS rate was calculated in pancreatic cancer patients with high tumor mutation burden(TMB)and low TMB.CCK-8 assay was used to examine the effect of ADAM28 on the viability of SW1990 cells.The ADAM28 and its co-expressed genes were analyzed in the cBioPortal for cancer genomics and subjected to GSEA pathway analysis.The correlations of ADAM28 with GSTP1,ABCC1,GSTM4,and BCL2 were analyzed based on TCGA data on pancreatic cancer.RESULTS RNA-sequence analysis identified that ADAM28 was overexpressed in gemcitabine-resistant cells,and gemcitabine treatment could induce the expression of ADAM28.The mRNA and protein levels of ADAM28 were elevated in gemcitabine-resistant SW1990 cells compared with parallel cells.Also,the expression of ADAM28 was upregulated in pancreatic tumor tissues against normal pancreatic tissues.Notably,ADAM28 was highly expressed in the classical type than in the basal tumor type.Furthermore,the high expression of ADAM28 was associated with low OS and RFS rates.Interestingly,the high levels of ADAM28 was associated with a significantly lower OS rate in the high TMB patients,but not in the low TMB patients.Moreover,overexpression of ADAM28 could reduce the cell viability inhibition by gemcitabine,and knockdown of ADAM28 could enhance the proliferation inhibition by gemcitabine.The GSEA analysis showed that ADAM28 was related to the regulation of drug metabolism,and ADAM28 was significantly positively correlated with GSTP1,ABCC1,GSTM4,and BCL2.CONCLUSION This study demonstrates that ADAM28 is overexpressed in pancreatic cancer,and closely involved in the regulation of gemcitabine resistance.Overexpression of ADAM28 is a novel prognostic biomarker in pancreatic cancer.

Fixed Dose Rate versus Standard Dose Rate Infusion of Gemcitabine and Cisplatin in Advanced Stage Non-Small Cell Lung Cancer

Background: Comparing the efficacy and safety of gemcitabine at a fixed-dose rate (FDR) infusion (10 mg/m2/min) with the standard dose rate infusion in patients with locally advanced and metastatic non-small squamous cell carcinoma (NSCLC). Methods: The study randomized 60 patients with confirmed diagnosis of NSCLC to receive gemcitabine at a dose of 1000 mg/m2 on days 1 and 8 given as a 30-min infusion (Arm A) or at a rate of 10 mg/m2/min (Arm B). Cisplatin 75 mg/m2 was administered intravenously on day 2 in both arms. Results: No difference in overall response rate (46.6% versus 43.3%). Median time to progression for Arm A was 7 months (95% CI, 6.207 - 7.793 months), versus 6 months for Arm B (95% CI, 4.990 - 7.010 months). Median survival time was comparable [12 months (95% CI, 8.588 - 15.412 months) versus 11 months (95% CI, 9.066 - 12.934 months)] respectively. Two-year survival (18% versus 11%, p = 0.38) was detected. No treatment related deaths occurred. Main hematological toxicities were grade I and II neutropenia, in 36.7% and 53.3% respectively (p = 0.044). Grade III anemia was observed in 10% and 6.7% in both arms respectively (p = 0.024). Grade I and II nausea and vomiting was observed in 50% and 46.7%. Conclusions: FDR gemcitabine in combination with cisplatin had equivalent efficacy and more severe hematologic toxicities compared to the standard 30-min gemcitabine infusion with cisplatin in patients with advanced NSCLC.

Expression of RRM1 and its association with resistancy to gemcitabine-based chemotherapy in advanced nasopharyngeal carcinoma

Gemcitabine has high activity against nasopharyngeal carcinoma(NPC).The level of ribonucleotide reductase subunit M1(RRM1) expression is closely related to the efficacy of gemcitabine on non-small cell lung cancer and pancreatic cancer.However,the expression of RRM1 and its association with sensitivity to gemcitabine-based chemotherapy in advanced NPC is not known.In this study,we retrospectively collected 48 formalin-fixed,paraffin-embedded NPC tissues to evaluate the expression of RRM1 using immunohistochemistry.All patients were diagnosed and treated with gemcitabine-based chemotherapy at Sun Yat-sen University Cancer Center.RRM1 expression was positive in 17(35%) patients.RRM1 expression was not associated with sex,age,performance status,WHO histological type,number of distant metastases,previous treatment,or cycles of gemcitabine-based chemotherapy(P> 0.05).The progression-free survival of the RRM1-positive group was shorter than that of the RRM1-negative group(5 months vs.7 months,P = 0.036),and the response rate of the RRM1-positive group was somewhat lower than that of the RRM1-negative group(51.6% vs.35.3%,P = 0.278).There was no significant difference in median survival between the RRM1-positive and RRM1-negative groups(22 months vs.19 months,P = 0.540).Our results show that RRM1-negative expression is related with longer progression-free survival in advanced NPC patients treated with gemcitabine-based regimens.

Early monitoring of response to antimetabolic treatment of gemcitabine:A comparison of ^(18)F-FLT and ^(18)F-FDG uptake in Patu 8988 human pancreatic carcinoma cells

It is essential to predict the treatment efficacy of pancreatic carcinoma early.The purpose of this study was to examine whether ^(18)F-FDG(2'-deoxy-2'-[^(18)F]fiuoro-D-glucose) or ^(18)F-FLT(3'-deoxy-3'-^(18)F-fluorothymidine) PET can be used for chemosensitivity testing by investigating the binding characteristic of ^(18)F-FDG or ^(18)F-FLT with Patu 8988 human pancreatic carcinoma cell and the influence of gemcitabine in the uptake of ^(18)F-FDG or ^(18)F-FLT on Patu 8988.Under the conditions of 1×10~6 cells,3.7 kBq ^(18)F-FDG or ^(18)F-FLT,and incubation at 37℃for 100 min,the cell uptake of ^(18)F-FDG and ^(18)F-FLT was(60.60±3.05)%and(50.57±2.81)%,respectively.There was a significant decrease in TKl-LI(thymidine kinase 1 labeling index) 24 h after administration of gemcitabine.The uptakes of ^(18)F-FDG and ^(18)F-FLT were negatively correlated with the doses of gemcitabine(r= -0.928 for ^(18)F-FDG,r= -0.876 for ^(18)F-FLT,P<0.01).When same doses of gemcitabine were administered,the ^(18)F-FLT uptake inhibition rate was significantly higher than that of ^(18)F-FDG(P<0.01).These results indicate that the response to gemcitabine could be predicted as early as 24 h by ^(18)F-FDG or ^(18)F-FLT PET scans.^(18)F-FLT is more sensitive than ^(18)F-FDG to predict the response to therapy.

Intraarterial chemotherapy with gemcitabine and cisplatin in locally advanced or recurrent penile squamous cell carcinoma

The prognosis of locally advanced or recurrent squamous cell carcinoma(SCC) of the penis after conventional treatment is dismal. This study aimed to evaluate the therapeutic effects of intraarterial chemotherapy with gemcitabine and cisplatin on locally advanced or recurrent SCC of the penis. Between April 1999 and May 2011, we treated 5 patients with locally advanced penile SCC and 7 patients with recurrent disease with intraarterial chemotherapy. The response rate and toxicity data were analyzed, and survival rates were calculated. After 2 to 6 cycles of intraarterial chemotherapy with gemcitabine and cisplatin, 1 patients with locoregionally advanced disease achieved a complete response, and 4 achieved partial response. Of the 7 patients with recurrent disease, 2 achieved complete response, 3 achieved partial response, 3 had stable disease, and 1 developed progressive disease. An objective tumor response was therefore achieved in 10 of the 12 patients. The median overall survival for the patients was 24 months(range, 10-50 months). Three out of 10 patients who responded were long-term survivors after intraarterial chemotherapy. Intraarterial chemotherapy with gemcitabine and cisplatin may be effective and potentially curative in locoregionally advanced or recurrent penile SCC. The contribution of this therapy in the primary management of advanced or recurrent penile SCC should be prospectively investigated.

Poorly differentiated endocrine carcinoma of the pancreas responded to gemcitabine:Case report

Poorly differentiated endocrine carcinoma (PDEC) of the pancreas is a rare and aggressive tumor. First-line treatment is commonly a combination of etoposide and cisplatin, but there is no consensus regarding further treatment recommendations. In this report, we describe a case of pancreatic PDEC treated with gemcitabine as third-line chemotherapy. A 62-year-old man with pancreatic PDEC was administered etoposide plus cisplatin as first-line treatment; he then received irinotecan for tumor relapse. However, because irinotecan induced ileus in this patient, we chose gemcitabine as thirdline chemotherapy. After two cycles of gemcitabine (1000 mg/m2 on days 1, 8 and 15 every 4 wk), a partialtumor response was noted by computed tomography (approximately 68% reduction in tumor size). Our patient survived for 15 mo after diagnosis. This is a rare case of unresectable pancreatic PDEC, which showed a partial response to gemcitabine after the failure of two other regimens. Gemcitabine could be an effective treatment option for pancreatic PDEC that is resistant to other treatments.