Holistic Approach in the Treatment of Actinic Keratosis: Benefits and Disadvantages of 5-Fluorouracil, Imiquimod, Diclofenac and Curaderm

Background Actinic keratosis is the most prevalent premalignant skin disorder in the white population. Current guidelines provide no clear recommendations about preferred treatments. Methods The parameters;effectiveness, treatment duration, recurrence, side effects and cost of treatment were investigated for three frequently used topical therapies which were then compared with a most recent developed topical therapy. Published clinical data obtained from the literature was used to compare these parameters for 5-fluorouracil, imiquimod and diclofenac and relate them with the newly developed Curaderm. Results A wide variation in the concentrations of the active anti-keratotic ingredients, application frequency, duration of treatment, recurrence rates and cost of treatment exist between the different topical therapies. The efficacy rates and side effects were less variable. Overall, Curaderm is the most suitable treatment for actinic keratosis. Clinical evidence is presented illustrating the effects of Curaderm on field-directed treatments and solitary treatments of actinic keratoses. Conclusions Current medical guidelines do not provide clear recommendations on which treatment approach for actinic keratosis is preferred. Direct head-to-head comparison between treatments with emphasis on efficacy, safety, treatment duration, compliance, convenience, cosmetic outcome, patient acceptance and cost should be available to the patient, the practising physician, healthcare system and should assist in therapeutic treatment guidelines and policymaking. Given the very favourable profiles of these parameters with Curaderm when compared with other home-based treatments, it should be considered that Curaderm is first-in-line.

Cardiac Manifestations with Chemotherapeutic Agents: 5 Fluorouracil-Induced Coronary Artery Vasospasm

5-fluorouracil (5-FU) is a fluorinated, pyrimidine analog, antineoplastic agent that is used in the treatment of several solid organ cancers. Cardiotoxicity is uncommon but life-threatening manifestations such as myocardial infarction may manifest owing to 5-FU-induced coronary artery spasm. Administering smaller doses of the drug, more frequently than not, decreases the risk of cardiotoxicity compared to large doses or with continuous infusions. We present a case of ST-segment elevation in a patient without known coronary artery disease who had presented following continuous 5-FU infusion. Coronary angiogram confirmed absence of coronary artery disease and intravenous calcium channel blockers administration was commensurate with the patient’s improvement in symptoms. We discuss the literature on 5-FU and its association with coronary artery spasm, and also briefly review chemotherapy-induced cardiotoxicities to help better prepare internists and other primary health care providers to face similar challenges, particularly of the uncommon but potentially life-threatening manifestations.

肿瘤阳性显像剂5-^(18)F-fluorouracil的标记与动物实验

目的 探讨18F fluorouracil(FU)作为肿瘤阳性显像剂的可能性。方法 标记与合成了18F FU ,研究其在正常与荷瘤裸鼠中的生物分布 ,进行正常与荷瘤兔的PET显像。结果 HPLC及其他质控分析结果均证实18F FU动物实验与临床应用的可行性 ,生物分布及显像研究表明它在肿瘤组织中有较多的摄取。结论 18F FU是一种有潜力的肿瘤阳性显像剂。

亲肿瘤显像剂5-^(18)F-Fluorouracil(^(18)F-FU)的标记合成研究

用18 F F2 与Uracil的直接标记法合成了 5- 18F -Fluorouracil,探索18F -FU -PET显像对结肠直肠癌肝转移病人化疗前后疗效评价的意义。产品的放射化学纯 >95% ,放射性得率为 60 % ,pH值为 7,无菌性试验和热源试验均为阴性 ,这一结果为临床应用提供了保证。

Induction chemotherapy with docetaxel,cisplatin and fluorouracil followed by concurrent chemoradiotherapy for unresectable sinonasal undifferentiated carcinoma: Two cases of report

BACKGROUND Sinonasal undifferentiated carcinoma(SNUC) is a rare aggressive tumor that is often unresectable. Optimal treatment for patients with unresectable,locally advanced SNUC(LA-SNUC) has not been established,and the patient outcome remains poor. We report two cases of unresectable LA-SNUC in which induction chemotherapy with docetaxel,cisplatin and fluorouracil(TPF) followed by radiotherapy with concurrent cisplatin(CCRT),a standard treatment option for locally advanced head and neck cancer,demonstrated promising outcomes.CASE SUMMARY A 39-year-old man presented with tearing and pain in the right eye. A biopsy of the tumor invading the sinonasal cavities,right orbit and cranial base confirmed the diagnosis of LA-SNUC. Induction TPF chemotherapy induced remarkable tumor shrinkage and rapidly improved the symptoms. He subsequently received CCRT and achieved complete remission of the disease. The other case is a 21-year-old man who presented with worsening vision. The unresectable tumor involving the nasal septum and cranial base was pathologically diagnosed as SNUC. TPF chemotherapy followed by CCRT yielded complete remission of the disease with preserved visual function. Both patients have been disease-free for44 mo.CONCLUSION Induction TPF chemotherapy followed by CCRT may remarkably improve the outcomes in LA-SNUC patients.

Preparation and distribution of 5-fluorouracil ^(125)I sodium alginate-bovine serum albumin nanoparticles

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Interaction between cisplatin,5-fluorouracil and vincristine on human hepatoma cell line (7721)

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Cooperative inhibitory effect of sinomenine combined with5-fluorouracil on esophageal carcinoma

AIM:To investigate the inhibitory effects of sinomenine(SIN)combined with 5-fluorouracil(5-FU)on esophageal carcinoma in vitro and in vivo.METHODS:Esophageal carcinoma(Eca-109)cells were cultured in DMEM.The single or combined growth inhibition effects of SIN and 5-FU on the Eca-109 cells were examined by measuring the absorbance of CCK-8dye in living cells.Hoechst 33258 staining and an Annexin V/PI apoptosis kit were used to detect the percentage of cells undergoing apoptosis.Western blotting was used to investigate the essential mechanism underlying SIN and 5-FU-induced apoptosis.SIN at 25mg/kg and 5-FU at 12 mg/kg every 3 d,either combined or alone,was injected into nude mice and tumor growth inhibition and side effects of the drug treatment were observed.RESULTS:SIN and 5-FU,both in combination and individually,significantly inhibited the proliferation of Eca-109 cells and induced obvious apoptosis.Furthermore,the combined effects were greater than those of the individual agents(P<0.05).Annexin V/PI staining and Hoechst 33258 staining both indicated that the percentage of apoptotic cells induced by SIN and 5-FU combined or alone were significantly different from the control(P<0.05).The up-regulation of Bax and downregulation of Bcl-2 showed that the essential mechanism of apoptosis induced by SIN and 5-FU occurs via the mitochondrial pathway.SIN and 5-FU alone significantly inhibited the growth of tumor xenografts in vivo,and the combined inhibition rate was even higher(P<0.05).During the course of chemotherapy,no obvious side effects were observed in the liver or kidneys.CONCLUSION:The combined effects of SIN and 5-FU on esophageal carcinoma were superior to those of the individual compounds,and the drug combination did not increase the side effects of chemotherapy.

Synergistic anticancer properties of docosahexaenoic acid and 5-fluorouracil through interference with energy metabolism and cell cycle arrest in human gastric cancer cell line AGS cells

AIM: To explore the synergistic effect of docosahexaenoic acid(DHA)/5-fluorouracil(5-FU) on the human gastric cancer cell line AGS and examine the underlying mechanism.METHODS: AGS cells were cultured and treated with a series of concentrations of DHA and 5-FU alone or in combination for 24 and 48 h. To investigate the synergistic effect of DHA and 5-FU on AGS cells, the inhibition of cell proliferation was determined by MTT assay and cell morphology. Flow cytometric analysis was also used to assess cell cycle distribution, and the expression of mitochondrial electron transfer chain complexes(METCs)?Ⅰ, Ⅱ and Ⅴ in AGS cells was further determined by Western blot analysis. RESULTS: DHA and 5-FU alone or in combination could markedly suppress the proliferation of AGS cells in a significant time and dose-dependent manner. DHA markedly strengthened the antiproliferative effect of 5-FU, decreasing the IC50 by 3.56-2.15-fold in an apparent synergy. The morphological changes of the cells were characterized by shrinkage, cell membrane blebbing and decreased adherence. Cell cycle analysis showed a shift of cells into the G0/G1 phase from the S phase following treatment with DHA or 5-FU(G0/G1 phase: 30.04% ± 1.54% vs 49.05% ± 6.41% and 63.39% ± 6.83%, respectively, P < 0.05; S phase: 56.76% ± 3.14% vs 34.75% ± 2.35% and 25.63% ± 2.21%, respectively, P < 0.05). Combination treatment of DHA and 5-FU resulted in a significantly larger shift toward the G0/G1 phase and subsequent reduction in S phase(G0/G1 phase: 69.06% ± 2.63% vs 49.05% ± 6.41% and 63.39% ± 6.83%, respectively, P < 0.05; S phase: 19.80% ± 4.30% vs 34.75% ± 2.35% and 25.63% ± 2.21%, respectively, P < 0.05). This synergy was also reflected in the significant downregulation of the expression of METCs in AGS cells.CONCLUSION: Synergistic anticancer properties of DHA and 5-FU may involve interference with energy production of AGS cells via downregulation of METCs and cell cycle arrest.

Non-platinum-based chemotherapy for treatment of advanced gastric cancer:5-fluorouracil,taxanes,and irinotecan

Despite numerous advances in treatment options,advanced gastric cancer(AGC)remains a major public health issue and the leading cause of cancer-related deaths.Cisplatin is one of the most effective broadspectrum anticancer drugs for AGC and a doublet combination regimen of either cisplatin-based or 5-fluorouracil(5FU)-based chemotherapy is generally used for treatment of patients with AGC.However,there is still no consensus on the best regimen for treating AGC.Recently,various new chemotherapeutic agents,including oral 5FU,taxanes,and irinotecan,have been identified as improving the outcomes for AGC when used as a single agent or in combination with nonplatinum chemotherapy.Nonetheless,it is still unclear whether non-platinum-based chemotherapy is a viable treatment option for patients with AGC.Accordingly,this review focuses on the efficacy and tolerability of non-platinum-based chemotherapy for patients with AGC.

Extract of Cycas revoluta Thunb. enhances the inhibitory effect of 5-fluorouracil on gastric cancer cells through the AKT-mTOR pathway

BACKGROUND Gastric cancer is one of the most common and deadly malignancies worldwide.Despite recent medical progress, the 5-year survival rate of gastric cancer is still unsatisfactory. 5-fluorouracil(5-Fu) is one of the first-line antineoplastic treatments for gastric cancer, as it can effectively induce cancer cell apoptosis.However, the effect of 5-Fu is limited due to drug resistance of the malignant tumor. Previous studies have reported that Sotetsuflavone from Cycas revoluta Thunb. can markedly suppress lung cancer cell proliferation by apoptosis,though its effect on gastric cancer remains unknown.AIM To investigate the inhibitory effect of Cycas revoluta Thunb. and to determine whether it can overcome gastric cancer cell drug resistance to 5-Fu.METHODS Cell viability was examined to determine whether the natural extract of Cycas revoluta Thunb. induced gastric cancer cell death. The half-maximal effective concentration and the half-maximal lethal concentration were calculatede.Wound-healing and transwell assays were performed to examine gastric cancer cell motility. Clonogenic assays were performed to investigate the synergistic effects of Cycas revoluta Thunb. with 5-Fu, and apoptotic bodies were detected by Hoechst staining. Western blotting was performed to examine the expression of related proteins and to investigate the molecular mechanism of Cycas revoluta Thunb.-induced cancer cell apoptosis. The expressions of proteins, including mammalian target of rapamycin(mTOR) and p-AKT, were detected in different combinations of treatments for 48 h, then analyzed by ECL detection.RESULTS Gastric cancer cells were more sensitive to the natural extract of Cycas revoluta Thunb. compared to normal gastric epithelial cells, and the extract effectively inhibited gastric cancer cell migration and invasion. The extract improved the anti-cancer effect of 5-Fu by enhancing the chemosensitization of gastric cancer cells. Extract plus 5-Fu further reduced the expression of the drug-resistancerelated proteins p-AKT and mTOR after 48 h compared to 5-Fu alone. Compared to 5-Fu treatment alone, mTOR and p-AKT expression was significantly reduced by about 50% and 75%, respectively. We also found that the natural extract of Cycas revoluta Thunb. further increased 5-Fu-induced gastric cancer cell apoptosis. Expression of apoptosis-related protein X-linked inhibitor of apoptosis protein and apoptosis inducing factor were significantly reduced and increased,respectively, in the 5-Fu-resistant gastric cancer line SGC-7901/R treated with extract plus 5-Fu, while the expression of survivin did not change.CONCLUSION The natural extract of Cycas revoluta Thunb. effectively inhibited gastric cancer cell growth and enhanced the anti-cancer effect of 5-Fu through the AKT-mTOR pathway.

Raddeanin A promotes apoptosis and ameliorates 5-fluorouracil resistance in cholangiocarcinoma cells

BACKGROUND Bile duct cancer is characterized by fast metastasis and invasion and has been regarded as one of the most aggressive tumors due to the absence of effective diagnosis at an early stage.Therefore,it is in the urgent demand to explore novel diagnostic approaches and therapeutic strategies for bile duct cancer to improve patient survival.Raddeanin A(RA)is extracted from the anemone raddeana regel and has been demonstrated to play antitumor roles in various cancers.AIM To investigate the effects of RA treatment on bile duct cancer cells.METHODS In this study,four cholangiocarcinoma cell lines(RBE,LIPF155C,LIPF178C,and LICCF)treated with RA were used to test the cell viability.The RA-associated cell functional analysis,5-fluorouracil(5-Fu)effectiveness as well as cell cycle-and apoptosis-related protein expression were investigated.RESULTS RA reduced cell viability in a dose-dependent pattern in four cell lines,and the migration and colony formation abilities were also impaired by RA in RBE and LIPF155C cell lines.RA sensitized cell lines to 5-Fu treatment and enhanced the effects of 5-Fu in cholangiocarcinoma.Also,RA decreased protein expression of Wee1,while the combinational effect of RA and 5-Fu decreased protein expressions of cyclooxygenase-2,B cell lymphoma 2,and Wee1 but increased protein levels of Bax,cyclin D1,and cyclin E.CONCLUSION Taken together,the results suggest that RA acts as an anti-cancer agent and enhancer of 5-Fu in bile duct cancer cells via regulating multiple cell cycle and apoptosis-related proteins.This finding provides novel clues to exploring a novel antitumor drug for bile duct cancer.

Pharmacological Study on Antitumor Activity of 5-Fluorouracil-1-Acetic Acid and Its Rare Earth Complexes

The antitumor activity of 5 fluorouracil 1 acetic acid(HFAA) and its lanthanide complexes(La(FAA) 3, Eu(FAA) 3) were studied. The results show that HFAA, La(FAA) 3 and Eu(FAA) 3 with the concentrations of 1 0×10 -5 ～1 0×10 -2 μg·ml -1 inhibit the colony formation of leukemia cells(L 1210 ) and the growth of transplanted tumor sarcoma 180(S 180 ), hepatic carcinoma(HEPA) and ehrlich ascites tumor(EC) as well. The maximum inhibitory rate of Eu(FAA) 3 for S 180 is 38 4%, that HFAA and La(FAA) 3 for EC are 22 4% and 43 4%, respectively. The life prolongation rate of Eu(FAA) 3 for HEPA bearing mice is as long as 284%.

Should capecitabine replace 5-fluorouracil in the first-line treatment of metastatic colorectal cancer?

Fluoropyrimidines play a central role in the first-line treatment of metastatic colorectal cancer.Our aim was to review whether capecitabine was a safer,non-inferior,economically superior and more convenient alternative to 5-fluorouracil.Capecitabine has previously been compared to 5-fluorouracil-either as a monotherapy or in combination with oxaliplatin,irinotecan,or biological drugs-and has been found to have comparable efficacy and safety profiles.Furthermore,pharmacoeconomic data and patients’preferences for oral chemotherapy further favor capecitabine.Therefore,capecitabine appears to be an effective and safe alternative to fluorouracil in the first-line treatment of metastatic colorectal cancer.

Docetaxel, cisplatin, and 5-fluorouracil compared with epirubicin,cisplatin, and 5-fluorouracil regimen for advanced gastric cancer:A systematic review and meta-analysis

BACKGROUND As the first-line regimens for the treatment of advanced gastric cancer, both docetaxel, cisplatin, and 5-fluorouracil(DCF) and epirubicin, cisplatin, and 5-fluorouracil(ECF) regimens are commonly used in clinical practice, but there is still controversy about which is better.AIM To compare the efficacy and safety of DCF and ECF regimens by conducting this meta-analysis.METHODS Computer searches in PubMed, EMBASE, Ovid MEDLINE, Science Direct, Web of Science, The Cochrane Library and Scopus were performed to find the clinical studies of all comparisons between DCF and ECF regimens. We used progression-free survival(PFS), overall survival(OS), objective response rate(ORR), disease control rate(DCR), and adverse effects(AEs) as endpoints for analysis.RESULTS Our meta-analysis included seven qualified studies involving a total of 598 patients. The pooled hazard ratios between the DCF and ECF groups were comparable in PFS(95%CI: 0.58-1.46, P = 0.73), OS(95%CI: 0.65-1.10, P = 0.21),and total AEs(95%CI: 0.93-1.29, P = 0.30). The DCF group was significantly better than the ECF group in terms of ORR(95%CI: 1.13-1.75, P = 0.002) and DCR(95%CI: 1.03-1.41, P = 0.02). However, the incidence rate of grade 3-4 AEs was also greater in the DCF group than in the ECF group(95%CI: 1.16-1.88, P = 0.002),especially for neutropenia and febrile neutropenia.CONCLUSION With better ORR and DCR values, the DCF regimen seems to be more suitable for advanced gastric cancer than the ECF regimen. However, the higher rate of AEs in the DCF group still needs to be noticed.

Preparation of 5-fluorouracil-loaded chitosan nanoparticles and study of the sustained release in vitro and in vivo

The sustained-release properties of the biodegradable nano-drug delivery systems were used to improve the residence time of the chemotherapeutic agent in the body. These drug delivery systems were widely used to deliver chemotherapeutic drugs. The 5-fluorouracil loaded chitosan nanoparticles prepared in this paper have the above advantage. Here, we found that when the mass ratio of 5-fluorouracil and chitosan was 1:1, the maximum drug loading of nanoparticles was 20.13 ± 0.007%, the encapsulation efficiency was 44.28 ± 1.69%, the particle size was 283.9 ± 5.25 nm and the zeta potential was 45.3 ± 3.23 mV. The prepared nanoparticles had both burst-release and sustained-release phases in vitro release studies.In addition, the inhibitory effect of the prepared nanoparticles on gastric cancer SGC-7901 cells was similar to that of 5-fluorouracil injection, and the blank vector had no obvious inhibitory effect on SGC-7901 cells. In the pharmacokinetic study of rats in vivo, we found that AUC(0-t), MRT(0-t) and t1/2 z of nanoparticles were significantly increased in vivo compared with 5-fluorouracil solution, indicating that the prepared nanoparticles can play a role in sustained-release.

Effects of tacrolimus on proliferation, apoptosis, and fluorouracil sensitivity of liver cancer cell line of SMMC-7721

BACKGROUND: The effect of tacrolimus (FK506) and 5- fluorouracil (5-FU) on hepatocellular carcinoma remains elusive. The aim of this study was to assess the effect of ta- crolimus on the proliferation, and apoptosis in liver cancer cell line of SMMC-7721 and its sensitivity to fluorouracil (5- FU). METHODS: The liver cancer cell line of SMMC-7721 was cultured in vitro, and the MTT assay was used to examine the antiproliferative effect of FK506. Flow cytometry (FCM) was used to examine the effect of 5-FU alone or in combination with FK506 on the apoptosis and cell cycle of SMMC-7721 cells. RESULTS: FK506 produced concentration-dependent anti- proliferative effect on SMMC-7721 cells at all experimental concentrations(P <0.05), but no effect on induction of apo- ptosis. 5-FU induced apoptosis in a concentration-depen- dent manner, whereas the percentage of G0/G1-phase cells and proliferation index (PI) were increased with the in- creased concentration of 5-FU. Pretreatment with FK506 for 2 hours enhanced the effect of 5-FU on the induction of apoptosis. CONCLUSIONS: FK506 inhibits the growth of SMMC-7721 cells and enhances their sensitivity to 5-FU. This may be as- sociated with the synergic effect of FK506 and 5-FU in in- ducing apoptosis and G0/G1-phase stasis.

Caspase-8 in apoptosis of hepatoma cell induced by 5-fluorouracil

OBJECTIVE: To explore the relationship between the changes in the activity of caspase-8 and apoptosisof HepG2 cells induced by 5-fluorouracil （5-Fu）.METHODS: Human hepatoma HepG2 cells were treated with 5-Fu at the concentrations of 1×10-1,1×10-2, 1×10-3, 1×10-4, 1×10-5 mol/L and for 1, 2, 4, 8, 16, 24 hours, respectively. Thecaspase-8 activity was detected using caspase-8 fluorescent assay kit. The apoptotic rate of HepG2 cellsinduced by 5-Fu with or without the caspase-8 inhibitor IETD-FMK was measured by flow cytometry.RESULTS: Afer the HepG2 cells were trealed with 10-2 mol/L 5-Fu, the caspase-8 activity increasedgradually and reached the peak level （313.9±6.9） at 16 hours, then fell down. Compared with thecontrol group, the activity was still significantly higher （274.2±3.9 vs 68.3±3.6, P【0.01）. With theincreasing concentraion of 5-Fu, the caspase-8 activity was also increased; the activity in highconcentration 5-Fu was significantly higher than that in low concentration 5-Fu （370.5±4.7 vs313.7±6.9; 225.7±5.4 vs 183.3±4.8; 183.3±4.8 vs 124.0±6.2, P【0.01）. The caspase-8activity was the highest at 1×10-1 mol/L 5-Fu （370.5±4.7）. The caspase-8 activity in lowconcentration 5-Fu was higher than in the blank control group and inhibitor group （124.0±6.2 vs68.5±3.4; 124.0±6.2 vs 41.0±2.1, P【0.01）. IETD-FMK could block the activation of caspase-8and reduce the apoptosis of HepG2 cells induced by 5-Fu. The apoptotic rate of HepG2 cells in the 5-Fugroup was significantly different from that in the inhibitor group （P【0.01）.CONCLUSIONS: 5-Fu can induce apoptosis of HepG2 cells via caspase-8 signal transduction pathway,which can be blocked by IETD-FMK. 5-Fu promotes the increase of caspase-8 activity in a time- orconcentration-dependent manner.

1,3-Bis(2-chloroethyl)-1-nitrosourea enhances the inhibitory effect of Resveratrol on 5-fluorouracil sensitive/resistant colon cancer cells

AIM:To study the mechanism of 5-fluorouracil(5-FU)resistance in colon cancer cells and to develop strategies for overcoming such resistance by combination treatment.METHODS:We established and characterized a 5-FU resistance(5-FU-R)cell line derived from continuous exposure(25μmol/L)to 5-FU for 20 wk in 5-FU sensitive HCT-116 cells.The proliferation and expression of different representative apoptosis and anti-apoptosis markers in 5-FU sensitive and 5-FU resistance cells were measured by the MTT assay and by Western blotting,respectively,after treatment with Resveratrol(Res)and/or 1,3-Bis(2-chloroethyl)-1-nitrosourea(BCNU).Apoptosis and cell cycle arrest was measured by 4',6'-diamidino-2-phenylindole hydrochloride staining and fluorescence-activated cell sorting analysis,respectively.The extent of DNA damage was measured by the Comet assay.We measured the visible changes in the DNA damage/repair cascade by Western blotting.RESULTS:The widely used chemotherapeutic agents BCNU and Res decreased the growth of 5-FU sensitive HCT-116 cells in a dose dependent manner.Combined application of BCNU and Res caused more apoptosis in5-FU sensitive cells in comparison to individual treatment.In addition,the combined application of BCNU and Res caused a significant decrease of major DNA base excision repair components in 5-FU sensitive cells.We established a 5-FU resistance cell line(5-FU-R)from 5-FU-sensitive HCT-116(mismatch repair deficient)cells that was not resistant to other chemotherapeutic agents(e.g.,BCNU,Res)except 5-FU.The 5-FU resistance of 5-FU-R cells was assessed by exposure to increasing concentrations of 5-FU followed by the MTT assay.There was no significant cell death noted in5-FU-R cells in comparison to 5-FU sensitive cells after5-FU treatment.This resistant cell line overexpressed anti-apoptotic[e.g.,AKT,nuclear factorκB,FLICE-like inhibitory protein),DNA repair(e.g.,DNA polymerase beta(POL-β),DNA polymerase eta(POLH),protein Flap endonuclease 1(FEN1),DNA damage-binding protein 2(DDB2)]and 5-FU-resistance proteins(thymidylate synthase)but under expressed pro-apoptotic proteins(e.g.,DAB2,CK1)in comparison to the parental cells.Increased genotoxicity and apoptosis were observed in resistant cells after combined application of BCNU and Res in comparison to untreated or parental cells.BCNU increased the sensitivity to Res of 5-FU resistant cells compared with parental cells.Fifty percent cell death were noted in parental cells when 18μmol/L of Res was associated with fixed concentration(20μmol/L)of BCNU,but a much lower concentration of Res(8μmol/L)was needed to achieve the same effect in 5-FU resistant cells.Interestingly,increased levels of adenomatous polyposis coli and decreased levels POL-β,POLH,FEN1 and DDB2 were noted after the same combined treatment in resistant cells.CONCLUSION:BCNU combined with Res exerts a synergistic effect that may prove useful for the treatment of colon cancer and to overcome drug resistance.

Overexpression of CREPT confers colorectal cancer sensitivity to fluorouracil

AIM To investigate expression of cell cycle-related and expression-elevated protein in tumor(CREPT) in colorectal cancer(CRC) and determine its prognostic value in response to 5-fluorouracil(5-FU).METHODS The relative expression of CREPT in CRC tumor samples was determined using immunohistochemistry. The protein content in cell lines was analyzed by immunoblotting. Cell viability was measured with the CCK-8 assay. Cell cycle and apoptosis analyses were performed with flow cytometry.RESULTS CREPT was overexpressed in CRC tissues and correlated with histological grade. Clinicopathological analysis indicated that CREPT was positively related to tumor progression. Exogenous expression of CREPT stimulated cell proliferation and accelerated the cell cycle. More importantly, high expression of CREPT sensitized CRC cells to 5-FU treatment. Furthermore, we demonstrated that 5-FU elicited significant apoptosis in CREPT-positive cells.CONCLUSION Aberrant overexpression of CREPT contributes to tumorigenesis of CRC by promoting cell proliferation and accelerating the cell cycle, and confers sensitivity to 5-FU. CREPT is a potential prognostic biomarker for 5-FU in CRC.