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.

UGT1A1 predicts outcome in colorectal cancer treated with irinotecan and fluorouracil

AIM:To evaluate effects of UDP-glucuronosyltransferase1A1(UGT1A1) and thymidylate synthetase(TS) gene polymorphisms on irinotecan in metastatic colorectal cancer(mCRC).METHODS:Two irinotecan-and fluorouracil-based regimens,FOLFIRI and IFL,were selected as second-line therapy for 138 Chinese mCRC patients.Genomic DNA was extracted from peripheral blood samples before treatment.UGT1A1 and TS gene polymorphisms were determined by direct sequencing and restriction fragment length polymorphism,respectively.Gene polymorphisms of UGT1A1*28,UGT1A1*6 and promoter enhancer region of TS were analyzed.The relationship between genetic polymorphisms and clinical outcome,that is,response,toxicity and survival were assessed.Pharmacokinetic analyses were performed in a subgroup patients based on different UGT1A1 genotypes.Plasma concentration of irinotecan and its active metabolite SN-38 and inactive metabolite SN-38G were determined by high performance liquid chromatography.Differences in irinotecan and its metabolites between UGT1A1 gene variants were compared.RESULTS:One hundred and eight patients received the FOLFIRI regimen,29 the IFL regimen,and one irinotecan monotherapy.One hundred and thirty patients were eligible for toxicity and 111 for efficacy evaluation.One hundred and thirty-six patients were tested for UGT1A1*28 and *6 genotypes and 125 for promoter enhancer region of TS.Patients showed a higher frequency of wild-type UGT1A1*28(TA6/6) compared with a Caucasian population(69.9% vs 45.2%).No significant difference was found between response rates and UGT1A1 genotype,although wild-type showed lower response rates compared with other variants(17.9% vs 24.2% for UGT1A1*28,15.7% vs 26.8% for UGT1A1*6).When TS was considered,the subgroup with homozygous UGT1A1*28(TA7/7) and non-3RG genotypes showed the highest response rate(33.3%),while wild-type UGT1A1*28(TA6/6) with non-3RG only had a 13.6% response rate,but no significant difference was found.Logistic regression showed treatment duration was closely linked to clinical response.In toxicity comparison,UGT1A1*28 TA6/6 was associated with lower incidence of grade 2-4 diarrhea(27.8% vs 100%),and significantly reduced the risk of grade 4 neutropenia compared with TA7/7(7.8% vs 37.5%).Wild-type UGT1A1*6(G/G) tended to have a lower incidence of grade 3/4 diarrhea vs homozygous mutant(A/A) genotype(13.0% vs 40.0%).Taking UGT1A1 and TS genotypes together,lower incidence of grade 2-4 diarrhea was found in patients with non-3RG TS genotypes,when TA6/6 was compared with TA7/7(35.3% vs 100.0%).No significant association with time to progression(TTP) and overall survival(OS) was observed with either UGT1A1 or TS gene polymorphisms,although slightly longer TTP and OS were found with UGT1A1*28(TA6/6).Irinotecan PK was investigated in 34 patients,which showed high area under concentration curve(AUC) of irinotecan and SN-38,but low AUC ratio(SN-38G /SN-38) in those patients with UGT1A1*28 TA7/7.CONCLUSION:A distinct distribution pattern of UGT1A1 genotypes in Chinese patients might contribute to relatively low toxicity associated with irinotecan and 5-fluorouracil in mCRC patients.

Rosiglitazone enhances fluorouracil-induced apoptosis of HT-29 cells by activating peroxisome proliferator-activated receptor γ

AIM： To examine whether and how rosiglitazone enhances apoptosis induced by fluorouracil in human colon cancer （HT-29） cells. METHODS： Human colon cancer HT-29 cells were cultured in vitro and treated with fluorouracil and/or rosiglitazone. Proliferation and growth of HT-29 cells were evaluated by MTF assay and trypan blue exclusion methods, respectively. The apoptosis of HT-29 cells was determined by acridine orange/ethidium bromide staining and flow cytometry using PI fluorescence staining. The expressions of peroxisome proliferator-activated receptor γ （PPARγ）, Bcl-2 and Bax in HT-29 cells were analyzed by Western blot. RESULTS： Although rosiglitazone at the concentration below 30 μmol/L for 72 h exerted almost no inhibitory effect on proliferation and growth of HT-29 cells, it could significantly enhance fluorouracil-induced HT-29 cell proliferation and growth inhibition. Furthermore, 10 μmol/L rosilitazone did not induce apoptosis of HT-29 cells but dramatically enhanced fluorouracil-induced apoptosis of HT-29 cells. However, rosiglitazone did not improve apoptosis induced by fluorouracil in HT-29 cells pretreated with GW9662, a PPARγ antagonist. Meanwhile, the expression of Bax and PPAR7 was upregulated, while the expression of Bcl-2 was down regulated in HT-29 cells treated with rosiglitazone in a time-dependent manner. However, the effect of rosiglitazone on Bcl-2 and Bax was blocked or diminished in the presence of GW9662. CONCLUSION： Rosiglitazone enhances fluorouracilinduced apoptosis of HT-29 cells by activating PPARγ.

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

AIM To prepare 5 FU sodium alginate 125 I bovine serum albumin nanoparticles (BSA NP), to determine the radioactive count in different organs of rats at different time points after oral administration of 5 FU 125 I sodium alginate BSA NP and to calculate the kinetic parameters of its metabolism. METHODS Emulsion solidification method was used to prepare 5 FU 125 I sodium alginate BSA NP, and to determine its diameter under transmission electronic microscope (TEM). Then the rate of NP and external drug releasing velocity were measured. Radioactive counting in different organs of rats was made after oral administration of the NP by GAMA Counter, and the kinetic parameters of drug metabolism were calculated by handling the data with the two department model. RESULTS The average arithmatic diameter of the NP was 166nm ± 34nm , the rate of 5 FU was 32 8% and the cumulative external releasing ratio amounted to 84 0% within 72 hours. The NP was mainly distributed in the liver, spleen, lungs and kidneys after NP oral administration to rats. The micro radioautographic experiment showed that NP was distributed in the Kupffers cells of liver, liver parenchymal cells and the phagocytes of spleen and lungs. The kinetic parameters of matabolism were: T 1/2 =9 42h, C max =2 45×10 7Bq, T max =2 18h, AUC=148×10 9Bq. CONCLUSION NP is difficult to pass through the blood-cerebral barrier,and 125 I sodium alginate-BSA NP enters the body circulation by gastroin testinal passage.

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

AIM To evaluate the killing effects of CDDP, 5-Fu and VCR on human hepaoma cell line (7721).METHODS The median-effect principle was used.RESULTS Killing effects of the individual drug were enhanced as the median concentration increased. Antagonism was produced when two drugs were used at a higher concentration (CI＞1), and synergism was achiened when CI＜1. Finally, the effect was influenced by both the ratios of drug concentration and the sequence of administration.CONCLUSION The drug administration order and drug concentrations are significant factors that need to be considered in clinical practice.INTRODUCTIONThe combined chemotherapy for malignant carcinoma is desired to produce efficacious synergism between each drug, alleviate side effects of drugs and delay drug resistance. Clinically, the interaction (namely synergism, summation and antagonism) of different anticancer drugs in combination is usually evaluated by Chou-Talalay′s combination index (i.e., median-effect principle)[1-9]. In this paper the combination effect between Cisplatin (Cis), 5-Fluorouracil (5-Flu) and Vincristine (VCR) on human hepatoma cell line 7721, was analyzed in vitro.

Influence of L-methionine-deprived total parenteral nutrition with 5-fluorouracil on gastric cancer and host metabolism

AIM: To investigate the influence of L-methionine-deprived total parenteral nutrition with 5-FU on gastric cancer and host metabolism. METHODS: N-methyl-N'-nitro-nitrosoguanidine (MNNG) induced gastric cancer rats were randomly divided into four groups: Met-containing TPN group (n=11), Met-deprived TPN group (n =12), Met-containing TPN+5-FU group (n=11) and Met-deprived TPN+5-FU group (n=12). Five rats in each group were sacrificed after 7 days of treatment and the samples were taken for examination. The remaining rats in each group were then fed separately with normal diet after the treatment until death, the life span was noted. RESULTS: The tumors were enlarged in Met-containing group and shrank in Met-deprived group markedly after the treatment. The DNA index (DI) of tumor cells and the body weight (BW) of rats had no significant change in the two groups, however, the ratio of tumor cells'S phase was increased. The ratio of G2M phase went up in Met-containing group, but down in Met-deprived group. In the other two groups that 5-FU was added, the BW of rats, and the diameter of tumors, the DI of tumor cells, the S and G2M phase ratio of tumor cells were all decreased, particularly in Met-deprived plus 5-FU group. Pathological examination revealed that the necrotic foci of the tumor tissue increased after Met-deprived TPN treatment, and the nucleoli of tumor cells enlarged. In MetTPN+5-FU group, severe nuclear damage was also found by karyopyknosis and karyorrhexis, meanwhile there was slight degeneration in some liver and kidney cells. The serum free Met and Cysteine decreased markedly (P【0.001), while other amino acids, such as serum free serine and glutamine increased significantly (P【0.005). All the rats died of multiple organ failure caused by cancer metastasis. The average survival time was 18.6 days in Met-containing TPN group, 31 days in Met-deprived TPN group, 27.5 days in Met-containing TPN+5-FU group, and 43 days in Met-deprived TPN+5-FU group (P【0.05). CONCLUSION: Met-deprived TPN causes methionine starvation of tumor cells, and can enhance the anti-tumor effect of 5-FU and prolong the life span of gastric cancer bearing rats.

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.

Pneumatosis cystoides intestinalis after fluorouracil chemotherapy for rectal cancer

Pneumatosis cystoides intestinalis (PCI) is a relatively rare condition characterized by intraluminal gas in the gastrointestinal tract. Several chemotherapeutic agents have been reported to be associated with PCI, although fluorouracil-related PCI is extremely rare. We report a case of a 76-year old man who received adjuvant chemotherapy for rectal cancer with fluorouracil (FU) and leucovorin (LV). After 1 cycle of the treatment, he presented with diarrhea and abdominal pain. Abdominal radiogram revealed the presence of free air under the diaphragm and intramural gas in the intestine. Laparotomy was performed, showing a suspected diagnosis of perforation in the gastrointestinal tract. Intraoperative findings revealed penumatosis of the intestine without evidence of perforation. He was treated supportively and his symptoms improved. In conclusion, we should consider the possibility of PCI occurring in patients with malignancies during chemotherapy treatment.

The effect of adenovirus expressing wild-type p53 on 5-fluorouracil chemosensitivity is related to p53 status in pancreatic cancer cell lines

AIM:There are conflicting data about p53 function on cellular sensitivity to the cytotoxic action of 5-fluorouracil (5-FU). Therefore the objective of this study was to determine the combined effects of adenovirus-mediated wild-type (wt) p53 gene transfer and 5-FU chemotherapy on pancreatic cancer cells with different p53 gene status. METHODS:Human pancreatic cancer cell lines Capan-1^(p53mut), Capan-2^(p53wt),FAMPAC^(p53mut),PANC1^(p53mut),and rat pancreatic cancer cell lines AS^(p53wt) and DSL6A^(p53null) were used for in vitro studies.Following infection with different ratios of Ad- p53-particles (MOI) in combination with 5-FU,proliferation of tumor cells and apoptosis were quantified by cell proliferation assay (WST-1) and FACS (PI-staining).In addition,DSL6A syngeneic pancreatic tumor cells were inoculated subcutaneously in to Lewis rats for in vivo studies. Tumor size,apoptosis (TUNEL) and survival were determined. RESULTS:Ad-p53 gene transfer combined with 5-FU significantly inhibited tumor cell proliferation and substantially enhanced apoptosis in all four cell lines with an alteration in the p53 gene compared to those two cell lines containing wt-p53.In vivo experiments showed the most effective tumor regression in animals treated with Ad-p53 plus 5-FU.Both in vitro and in vivo analyses revealed that a sublethal dose of Ad-p53 augmented the apoptotic response induced by 5-FU. CONCLUSION:Our results suggest that Ad-p53 may synergistically enhance 5-FU-chemosensitivity most strikingly in pancreatic cancer cells lacking p53 function.These findings illustrate that the anticancer efficacy of this combination treatment is dependent on the p53 gene status of the target tumor cells.

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.

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.

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.

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.

Recent studies of 5-fluorouracil resistance in pancreatic cancer

Resistance to 5-fluorouracil(5-FU), an important anticancer drug, is a serious challenge in the treatment of pancreatic cancer. Equilibrative nucleoside transporter 1 and multidrug-resistance protein(MRP) 5 and MRP8, rather than P-glycoprotein, play important roles in 5-FU transport. Thymidylate synthase, dihydropyrimidine dehydrogenase, methylenetetrahydrofolate reductase and thymidine phosphorylase are four key enzymes involved in 5-FU metabolism. Other metabolic enzymes, including uridine monophosphate synthetase, also contribute to chemoresistance. Intracellular signaling pathways are an integrated network, and nuclear factor kappa-light-chain-enhancer of activated B cells, AKT and extracellular signal-regulated kinases are signaling pathways that are particularly relevant to 5-FU resistance. In addition, recent reports indicate that STAT-3 is a crucial survival protein. Proteomic assays provide a powerful tool for identifying target proteins and understanding the role of micro RNAs and stromal factors to facilitate the development of strategies to combat 5-FU resistance.

Breast Cancer Resistance Protein Expression and 5-Fluorouracil Resistance

Objective To filtrate breast cancer resistance protein （BCRP）-mediated resistant agents and to investigate clinical relationship between BCRP expression and drug resistance. Methods MTT assay was performed to filtrate BCRP-mediated resistant agents with BCRP expression cell model and to detect chemosensitivity of breast cancer tissue specimens to these agents. A high performance liquid chromatography （HPLC） assay was established, and was used to measure the relative dose of intracellular retention resistant agents. RT-PCR and immunohistochemistry （IHC） were employed to investigate the BCRP expression in breast cancer tissue specimens. Results MTT assay showed that the expression of BCRP increased with the increasing resistance of 5-fluorouracil （5-Fu） （P〈0.05, n=3） in the cell model, while HPLC assay indicated that the intracellular retention dose of 5-Fu was significantly correlated with the expression of BCRP （t=-0.897, P〈0.05, n=3）. A total of 140 breast cancer tissue specimens were collected. BCRP-positive expression was detected in forty-seven specimens by both RT-PCR and IHC. As shown by MTT assay subsequently, the resistance index （RI） of 47 BCRP-positive breast cancer tissue specimens to 5-Fu was 7-12 times as high as that of adjacent normal tissue samples. BCRP expression was related to 5-Fu resistance （R2=0.8124, P〈0.01）. Conclusion Resistance to 5-Fu can be mediated by BCRR Clinical chemotherapy for breast cancer patients can be optimized based on BCRP-positive expression.

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.