OBJECTIVE: To evaluate the expression of thymidylate synthase (TS) in myoepithelial cells (MECs) of salivary adenoid tissues and explore its clinical significance. METHODS: Immunohistochemical staining EnVision method was used to detect the expression of TS, P63, Calponin, CK5/6 and S-100 in 32 salivary gland specimens, including 10 non-neoplastic and salivary inflammation specimens, 11 mixed tumor specimens, 5 basal cell carcinoma specimens and 6 adenoid cyst carcinoma specimens. The specificity and sensitivity of TS as a specific molecular marker of salivary muscle epithelial cells were evaluated in comparison with P63, Calponin, CK5/6 and S-100. RESULTS: The expression pattern of TS in all the salivary gland tissue specimens was identical with that of p63. TS and P63 both showed strong immunohistochemical expressions in MECs of salivary adenoid tissue specimens. Calponin, CK5/6, and S-100 showed cytoplasmic/membranous expressions in the MECs. In addition, TS exhibited weak or moderate cytoplasmic expression in a few salivary gland epithelial cells, cancer cells and scattered stromal cells, with negative expression in the cell nuclei. The expression of TS in the MECs of all the salivary adenoid specimens was highly consistent with those of P63, Calponin, CK5/6 and S-100 (>0.05) Except for CK5/6 expression in Salivary inflammation and Salivary gland specimens. Kappa>0.75. The specificity and sensitivity of TS as a molecular marker of MECs were both 100%. CONCLUSIONS TS is a new specific marker of MECs for differential diagnosis of salivary gland tumors.
Adenoids ; Biomarkers, Tumor ; Carcinoma, Adenoid Cystic ; Epithelial Cells ; Humans ; Salivary Gland Neoplasms ; Thymidylate Synthase

PURPOSE: Identification of biomarkers to predict recurrence risk is essential to improve adjuvant treatment strategies in stage II/III gastric cancer patients. This study evaluated biomarkers for predicting survival after surgical resection. MATERIALS AND METHODS: This post-hoc analysis evaluated patients from the CLASSIC trial who underwent D2 gastrectomywith orwithout adjuvant chemotherapy (capecitabine plus oxaliplatin) at the Yonsei Cancer Center. Tumor expressions of thymidylate synthase (TS), excision repair cross-complementation group 1 (ERCC1), and programmed death-ligand 1 (PD-L1) were evaluated by immunohistochemical (IHC) staining to determine their predictive values. RESULTS: Among 139 patients, IHC analysis revealed high tumor expression of TS (n=22, 15.8%), ERCC1 (n=23, 16.5%), and PD-L1 (n=42, 30.2%) in the subset of patients. Among all patients, high TS expression tended to predict poor disease-free survival (DFS; hazard ratio [HR], 1.80; p=0.053), whereas PD-L1 positivity was associated with favorable DFS (HR, 0.33; p=0.001) and overall survival (OS; HR, 0.38; p=0.009) in multivariate Cox analysis. In the subgroup analysis, poor DFS was independently predicted by high TS expression (HR, 2.51; p=0.022) in the adjuvant chemotherapy subgroup (n=66). High PD-L1 expression was associated with favorable DFS (HR, 0.25; p=0.011) and OS (HR, 0.22; p=0.015) only in the surgery-alone subgroup (n=73). The prognostic impact of high ERCC1 expression was not significant in the multivariate Cox analysis. CONCLUSION: This study shows that high TS expression is a predictive factor for worse outcomes on capecitabine plus oxaliplatin adjuvant chemotherapy, whereas PD-L1 expression is a favorable prognostic factor in locally advanced gastric cancer patients.
Biomarkers ; Capecitabine ; Chemotherapy, Adjuvant ; Disease-Free Survival ; DNA Repair ; Humans ; Immunohistochemistry ; Prognosis ; Prospective Studies ; Recurrence ; Stomach Neoplasms ; Thymidylate Synthase

OBJECTIVETo investigate the influence of thymidylate synthase (TS) gene polymorphisms on high-dose methotrexate (HD-MTX)-related toxicities in childhood acute lymphoblastic leukemia (ALL).

METHODSA total of 73 children who were diagnosed with ALL between March 2011 and March 2013 were included into this study. Genomic DNAs were extracted from their peripheral blood. And then the genotypes of TS 5'-UTR were determined by direct DNA sequencing after PCR. The toxicity response of 73 patients receiving HD-MTX chemotherapy were observed and recorded, and plasma MTX concentrations at 42-48 hours after chemotherapy were measured.

RESULTSThe main HD-MTX-related toxicities of 73 patients receiving HD-MTX chemotherapy were neutropenia, decreased hemoglobin level, thrombocytopenia, liver toxicity, mucosal damage, and gastrointestinal reactions. There were no significant differences in the incidence rate of HD-MTX-related toxicities between children with different TS 5'-UTR genotypes after chemotherapy (P>0.05). TS 5'-UTR genotype was not significantly correlated with plasma MTX concentrations at 42-48 hours after chemotherapy (P>0.05).

CONCLUSIONSTS gene polymorphisms have no influence on the incidence of HD-MTX-related toxicities in childhood ALL.

Antimetabolites, Antineoplastic ; adverse effects ; Child ; Child, Preschool ; Female ; Genotype ; Humans ; Infant ; Male ; Methotrexate ; adverse effects ; Polymorphism, Genetic ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; genetics ; Thymidylate Synthase ; genetics

PURPOSE: The main objective of this study was to evaluate the association between polymorphisms of the target genes of pemetrexed and clinical outcomes in non-small cell lung cancer (NSCLC) patients treated with pemetrexed. MATERIALS AND METHODS: We assessed polymorphisms at 8 sites in 4 genes [thymidylate synthase (TS), dihydrofolate reductase (DHFR; 1610, 680, 317, intron 1), methylenetetrahydrofolate reductase (MTHFR; 677, 1298), glycinamide ribonucleotide formyl transferase (GARFT; 2255)] associated with pemetrexed metabolism using polymerase chain reaction, gene scanning, and restriction fragment length polymorphism analysis in 90 patients with adenocarcinoma of the lung. RESULTS: Survival was significantly longer with pemetrexed in patients with TS 3RGCC/3RGCC or 3RGGC/3RGGC compared with the other groups (PFS; 5.2 months vs. 3.7 months, p=0.03: OS; 31.8 months vs. 18.5 months, p=0.001). Patients with DHFR 680CC experienced fatigue more frequently (50% vs. 8.6%, p=0.008). Polymorphisms of MTHFR and GARFT were not significantly associated with clinical outcomes of pemetrexed. CONCLUSION: The TS genotype was associated with survival and one DHFR polymorphism was associated with fatigue in NSCLC patients treated with pemetrexed. Further large prospective studies are required to identify other biomarkers that affect patients being treated with pemetrexed for adenocarcinoma of the lung.
Adenocarcinoma/*drug therapy/*genetics/mortality ; Adult ; Aged ; Aged, 80 and over ; Antimetabolites, Antineoplastic/pharmacology/*therapeutic use/toxicity ; Female ; Glutamates/pharmacology/*therapeutic use/toxicity ; Guanine/*analogs & derivatives/pharmacology/therapeutic use/toxicity ; Humans ; Lung Neoplasms/*drug therapy/*genetics/mortality ; Male ; Methylenetetrahydrofolate Reductase (NADPH2)/genetics ; Middle Aged ; Pharmacogenetics ; Phosphoribosylglycinamide Formyltransferase/genetics ; *Polymorphism, Single Nucleotide ; Tetrahydrofolate Dehydrogenase/genetics ; Thymidylate Synthase/genetics

OBJECTIVE: To analyze the impact of β-tubulin-III (TUBB3), thymidylate synthase (TS) and excision repair cross complementation group 1 (ERCC1) mRNA expression on chemoresponse and clinical outcome of patients with advanced gastric cancer treated with TXT/CDDP/FU (DCF) regimen chemotherapy. METHODS: The study population consisted of 48 patients with advanced gastric cancer. All patients were treated with DCF regimen palliative chemotherapy. The mRNA expressions of TUBB3, TS and ERCC1 of primary tumors were examined by multiplex branched-DNA liquid chip technology. RESULTS: The patients with low TUBB3 mRNA expression had higher response rate to chemotherapy than patients with high TUBB3 expression (P=0.011). There were no significant differences between response rate and TS or ERCC1 expression pattern. Median overall survival (OS) and median time to progression (TTP) were significantly longer in patients with low TUBB3 mRNA expression (P=0.002, P<0.001). TS or ERCC1 expression was not correlated with TTP and OS. In the combined analysis including TUBB3, TS and ERCC1, the patients with 0 or 1 high expression gene had better response rate, TTP and OS than the remaining patients (all P<0.001). Multivariate analysis revealed that ECOG (Eastern Cooperative Oncology Group)≥2 (HR=2.42, P=0.009) and TUBB3 (HR=2.34, P=0.036) mRNA expression significantly impacted on OS. CONCLUSION High TUBB3 mRNA expression is correlated with resistance to DCF regimen chemotherapy. TUBB3 might be a predictive and prognostic factor in patients with advanced gastric cancer treated with TXT-based chemotherapy. The combined evaluation of TUBB3, TS and ERCC1 expression can promote the individual treatment in advanced gastric cancer.
Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Biomarkers, Tumor ; metabolism ; DNA-Binding Proteins ; genetics ; metabolism ; Drug Resistance, Neoplasm ; Endonucleases ; genetics ; metabolism ; Humans ; RNA, Messenger ; genetics ; metabolism ; Stomach Neoplasms ; drug therapy ; genetics ; Thymidylate Synthase ; genetics ; metabolism ; Treatment Outcome ; Tubulin ; genetics ; metabolism

BACKGROUNDSeveral studies have evaluated the association between polymorphisms of thymidylate synthase (TS) and cancer risk in diverse populations but with conflicting results. By pooling the relatively small samples in each study, it is possible to evaluate the association using a meta-analysis.

METHODSA comprehensive search was conducted to identify all case-control studies on TS on a 28-bp tandem repeats in 5'untranslated region (5'UTR) and a 6-bp insertion (ins) and deletion (del) mutation in 3'UTR of the gene and cancer risk. Meta-analysis was conducted using a fixed and random effect model.

RESULTSOur meta-analysis on a total of 13 307 cancer cases and 18 226 control subjects from 37 published case-control studies showed no significant association between the risk of cancer and the 5'UTR 28-bp tandem repeats polymorphism (3R/3R vs. 2R/2R: OR = 1.06, 95%CI, 0.93 - 1.20) or the 3'UTR 6-bp ins/del polymorphism (del6/del6 vs. ins6/ins6: OR = 0.93, 95%CI, 0.81 - 1.08) with significant between-study heterogeneity. In the cancer type- and ethnic subgroup-stratification analyses, we did not find any association between TS polymorphisms and cancer risk either.

CONCLUSIONTS 5'UTR 28-bp tandem repeats and 3'UTR 6-bp ins/del polymorphisms may not be associated with cancer risk.

3' Untranslated Regions ; genetics ; 5' Untranslated Regions ; genetics ; Case-Control Studies ; Genetic Predisposition to Disease ; genetics ; Humans ; Neoplasms ; epidemiology ; genetics ; Polymorphism, Genetic ; genetics ; Tandem Repeat Sequences ; genetics ; Thymidylate Synthase ; genetics

PURPOSE: The purpose of this study is to suggest a probable problem in chemosensitivity tests performed in practice and to speculate on practicable measures for more accurate chemosensitivity evaluation. METHODS: Three colorectal cancer cells (RSC, RRC1, and RRC2) were treated with 5-fluorouracil (5-FU). Inhibition percentage (%inhibition) of cancer cells and relative quantitation of thymidylate synthase (TS) mRNA were measured on day 2, day 5 after replacement of 70% media on day 2, day 7, and day 3 after replacement of all media on day 7. Doses that produced 50% inhibition (Dm) were calculated to evaluate drug effect. Relative quantitation of TS mRNA and correlations between TS mRNA levels and 5-FU concentrations were analyzed. RESULTS: RRC1 was more resistant than RRC2 on day 7, but Dm value of RRC2 increased three days after replacement of media from 12.3 to 18.1. Mean TS mRNA levels of RSC on D2 and D7 were significantly lower than those of RRC1 and RRC2, respectively (P = 0.004, P = 0.004 on D2; P = 0.010, P = 0.006 on D7). TS mRNA levels in RRC1 were significantly reversely correlated with 5-FU concentrations on day 2 (correlation coefficient = -0.867, P = 0.015). On the other hand, correlations were not significant in RRC2 (r = 0.067). CONCLUSION: Evaluating %inhibition of cancer cells at one point in chemosensitivity tests seems to be inadequate in determining chemotherapeutic regimens. Multilateral approaches, such as trials evaluating cancer cell survival before and after media replacement and correlations between TS mRNA levels and 5-FU concentrations, needs to be implemented for the practical application of chemosensitivity tests.
Cell Line ; Cell Survival ; Colorectal Neoplasms ; Fluorouracil ; Hand ; RNA, Messenger ; Thymidylate Synthase

OBJECTIVETo investigate the effect of the RNAi and the chemotherapy drugs nolatrxed on the expression of thymidylate synthase(TS) and the growth of the colorectal carcinoma LOVO cells.

METHODSThe siRNA was constructed targeting the human TS gene, and then transfected into the human colorectal cancer LOVO cells. RT-PCR and Western blot technique were used to observe the TS gene and protein expression levels, and MTT was used to detect cell proliferation after silencing the TS gene. In addition, siRNA and nolatrxed were applied to the LOVO cells to observe the TS protein expression and cell growth.

RESULTSTS siRNA significantly reduced the expression of TS gene and protein in LOVO cells, and inhibited cell growth. The IC50 value of LOVO cells was (1.46±0.25) μmol/L in TS siRNA combined with nolatrexed group, (6.81±0.31) μmol/L in the negative control group, and (6.47±0.43) μmol/L in the single nolatrexed group. After treatment of TS siRNA combined with nolatrexed on LOVO cells for 36 hours, the apoptosis index was higher than that in single TS siRNA and nolatrexed[(62.12±0.89)% vs.(21.56±0.67)% and(40.51±0.83)%, both P<0.05].

CONCLUSIONTS siRNA can partly suppress the expression of TS gene in LOVO cells, inhibit cell proliferation, promote cell apoptosis and enhance cell sensitivity to apoptosis induced by nolatrexd.

Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Colorectal Neoplasms ; enzymology ; pathology ; Humans ; Quinazolines ; pharmacology ; RNA Interference ; Thymidylate Synthase ; genetics ; metabolism

BACKGROUNDThymidylate synthase (TS) is a key regulatory enzyme for de novo DNA synthesis. TS activity is also an important determinant of the response to chemotherapy with fluoropyrimidine prodrugs, and its expression may be affected by gene polymorphisms. In this study, we investigated the associations between polymorphisms of the TS gene and its protein expression, and the implications on the efficacy of 5-fluorouracil (5-FU) in pancreatic cancer cells.

METHODSGenotypes based on the 28-bp TS tandem repeat for pancreatic cell lines were determined by electrophoretic analysis of PCR products. A single nucleotide polymorphism (SNP) at nucleotide 12 of the second 28-bp repeat of the 3R allele was determined by nucleotide sequencing. The chemosensitivity of pancreatic carcinoma cells to 5-FU in vitro was evaluated using Cell Counting Kit-8 (CCK-8). TS protein expression was analyzed by Western blotting.

RESULTSSeven pancreatic carcinoma cell lines had different genotypes in terms of the 28-bp TS tandem repeat, as follows: homozygous 2R/2R (T3M4 and BxPC-3 cells), heterozygous 2R/3R (AsPC-1, Capan-1, and SU86.86), and homozygous 3R/3R (PANC-1 and COLO357). The optical density ratio of genotypes 3R/3R, 2R/2R and 2R/3R was 1.393 ± 0.374, 0.568 ± 0.032 and 0.561 ± 0.056, respectively. Cells with the 2R/3R or 3R/3R genotypes were further analyzed for the G to C SNP at nucleotide 12 of the second 28-bp repeat of the 3R allele, yielding heterozygous 2R/3Rc (AsPC-1, Capan-1, and SU86.86), homozygous 3Rg/3Rg (COLO357) and homozygous 3Rc/3Rc (PANC-1). The optical density ratio of homozygous 3Rg/3Rg cells and homozygous 3Rc/3Rc cells was 1.723 ± 0.062 and 1.063 ± 0.134, respectively, and this difference was statistically significant (P < 0.05). Cells with the 2R/2R and 2R/3R genotypes of TS were hypersensitive to 5-FU in vitro as compared with those with the 3R/3R cells.

CONCLUSIONSPolymorphisms in the TS gene influenced its protein expression and affected sensitivity of 5-FU in seven pancreatic cancer cell lines. Cells with the 3R/3R genotype had higher TS protein expression than the 2R/2R or 2R/3R genotypes. Cells of the 3R/3R genotype with high TS protein expression were shown lower 5-FU sensitivity than cells with the 2R/2R or 2R/3R genotypes. These data warrant large-scale clinical studies to assess the role of polymorphisms in the TS gene on its protein expression and chemosensitivity to 5-FU in pancreatic cancer.

Blotting, Western ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Fluorouracil ; pharmacology ; Humans ; Minisatellite Repeats ; genetics ; Pancreatic Neoplasms ; genetics ; Polymerase Chain Reaction ; Polymorphism, Genetic ; genetics ; Polymorphism, Single Nucleotide ; genetics ; Thymidylate Synthase ; genetics

PURPOSE: The genetic polymorphism and intracellular activity of methylenetetrahydrofolate reductase (MTHFR) and thymidylate synthase (TS) is clinically associated with carcinogenesis and biological therapeutic effect in gastrointestinal malignancies. We aimed to elucidate the susceptibility of gastric cancer according to MTHFR and TS gene polymorphism. METHODS: This study was designed as a hospital-based case-control study in a single institute. The gastric cancer group (n=300) for the study was diagnosed at first time as tubular adenocarcinoma, and the control group (n=100) was diagnosed as no malignancy in the endoscopic biopsy. The genetic polymorphism of TS and MTHFR were confirmed by PCR. RESULTS: The MTHFR mutant type had a more than 2-fold increased risk of developing gastric cancer (RR: 2.341). But, only heterozygote type (677CT) revealed significantly higher susceptibility compared to wild type (RR: 2.581). In TS gene genotype, the mutant genotype rate (2R/3R and 3R/3R) was significantly higher in gastric cancer group compared to control group (P=0.008), and the mutant type had a more than 3-fold increased risk of developing gastric cancer (RR: 3.222). In combined MTHFR and TS, 677CT+2R/3R and 677CT+3R/3R there was more than a 3-fold increased risk rate of developing gastric cancer compared with other combinations (RR, 3.474 in 677CT with 2R/3R; RR, 3.895 in 677CT with 3R/3R). CONCLUSION: This study shows a significant association between the MTHFR and TS polymorphisms and susceptibility to gastric cancer, providing a genetic basis. The polymorphisms study of two genes could be applied as susceptibility markers, clinically, for gastric cancer.
Adenocarcinoma ; Biopsy ; Case-Control Studies ; Genotype ; Heterozygote ; Methylenetetrahydrofolate Reductase (NADPH2) ; Polymerase Chain Reaction ; Polymorphism, Genetic ; Stomach Neoplasms ; Thymidylate Synthase