Activities of thymidylate synthase and dihydropyrimidine dehydrogenase in patients with colorectal cancer]

Between 1998 and 2001, 82 colorectal cancers were resected in our hospital. The activities of TS and DPD were evaluated. TS activities in tumor tissues were significantly higher than in normal tissue, but the DPD activities had no significant difference between them. TS and DPD showed a correlation between normal and tumor tissues in stage III or IV patients. The TS value of patients with recurrence tended to be higher than that of patients with no recurrence. Especially in stage I or II patients with recurrence, who were administered 5-FU before recurrence, the TS value was significantly higher than in non-treated patients. In stage III or IV patients, it was considered that DPD prevention was important for 5-FU to effectively prevent TS. The TS value might be a new prospective risk factor for recurrence. Moreover, TS and DPD would be the index of biological malignancy.     

Thymidylate synthase and dihydropyrimidine dehydrogenase gene expressions in colorectal cancer using the Danenberg tumor profile method

Thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) have been identified as a predictor of response to 5-fluorouracil (5-FU). Danenberg et al. developed a technology to evaluate gene expressions in formalin-fixed paraffin-embedded (FFPE) specimens (DTP; Danenberg tumor profile). In this study, TS and DPD gene expressions were measured in 47 primary colorectal cancer tumors and 12 metastatic tumors using FFPE specimens. In primary tumors, expression of TS genes in cancerous tissues was statistically higher than in stromal tissues, while DPD gene expressions in stromal tissues were higher than those in cancerous tissues. The median TS mRNA level was 0.86 in hepatic metastasis and 1.95 in lymph node metastasis. The median DPD mRNA level was 0.86 in hepatic metastasis and 1.96 in lymph node metastasis. Both gene expressions differed among primary tumors and metastatic tumors, especially in metastatic sites. DTP might be useful to evaluate the 2 gene expressions in colorectal cancer. Further studies would be needed to clarify the mechanisms of difference of gene expressions in cancerous and stromal tissues, or in primary tumors and metastatic tumors.     

Microsatellite instability in colorectal cancer and association with thymidylate synthase and dihydropyrimidine dehydrogenase expression

Background  

Microsatellite instability (MSI) refers to mutations in short motifs of tandemly repeated nucleotides resulting from replication errors and deficient mismatch repair (MMR). Colorectal cancer with MSI has characteristic biology and chemosensitivity, however the molecular basis remains unclarified. The association of MSI and MMR status with outcome and with thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) expression in colorectal cancer were evaluated.     

Thymidylate synthase and dihydropyrimidine dehydrogenase activity in a metastatic liver tumor from colorectal cancer

The value of thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) activity in metastatic liver tumor from colorectal cancer as predictive parameters for hepatic artery infusion (HAI) chemotherapy with 5-FU was investigated. Thirteen patients with metachronous liver metastases underwent hepatic resection and primary site colectomy. We measured TS and DPD activity in normal colonic mucosa, primary colon tumor, and metastatic liver tumor in these patients. The TS (pmol/g-tissue) of primary tumor, metastatic tumor, and normal colonic mucosa was 6.6 +/- 1.40 (mean +/- SE), 3.2 +/- 0.83 and 2.5 +/- 0.83 respectively. The DPD (pmol/min/mg/protein) of primary tumor, metastatic tumor, and normal colonic mucosa was 31.7 +/- 5.49, 82.1 +/- 12.5 and 50.6 +/- 8.46, respectively. There was significant relationship between DPD activity level and recurrence. It is suggested that 5-FU catabolism in metastatic liver tumor was increased, and DPD activity may be a valuable predictive marker for tumor response to HAI therapy.     

Polymorphisms in the thymidylate synthase and dihydropyrimidine dehydrogenase genes predict response and toxicity to capecitabine-raltitrexed in colorectal cancer

Pharmacogenetics is an increasingly useful field where the genetic studies are becoming an important tool for predicting drug toxicity and/or efficacy. Thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) gene polymorphisms could be highly informative tools in the clinical handling of colorectal cancer patients, who are following fluoropyrimidine based chemotherapy. Fifty-eight patients, with non-resectable metastatic colorectal cancer, were treated with capecitabine and raltitrexed, every three weeks. Patients were divided in a good-response group (complete and partial response) and a poor-response group (stable and progression). A genotype panel TS-DPD was evaluated. Results show that TS genotype analysis clearly differentiates patients with a worst response to a 5-fluorouracil based chemotherapy. DPD genotype was shown to be highly informative for prediction of toxicity of the treatment. These polymorphisms could represent an accurate, rapid and effective determination panel, indicative of resistance and toxicity for patients undergoing fluoropyrimidine based treatment.     

Expression of thymidylate synthase, orotate phosphoribosyltransferase and dihydropyrimidine dehydrogenase in thymic epithelial tumors

Background

It remains unclear whether thymidylate synthase (TS), orotate phosphoribosyltransferase (OPRT) and dihydropyrimidine dehydrogenase (DPD) expressions are associated with the pathogenesis of thymic epithelial tumors. Therefore, we investigated the expression of TS, OPRT and DPD in thymic epithelial tumors.

Patients and methods

Fifty-six patients with thymic epithelial tumors were included in this study. Tumors sections were stained by immunohistochemistry for TS, OPRT, DPD, microvessel density (MVD) determined by CD34, and p53. We also conducted in vitro study of TS, OPRT and DPD expression using thymic carcinoma, thymic tumor and thymic fibroblast cell lines.

Results

TS, OPRT and DPD were expressed in 61%, 48% and 41%, respectively. High grade malignancy is significantly associated with higher expression of TS, OPRT and DPD in thymic epithelial tumors. These biomarkers were closely associated with p53 and MVD, and the overexpression of TS and DPD was a prognostic marker for predicting poor outcome in univariate analysis. Our in vitro study showed that marked overexpression of TS and OPRT was observed in thymic carcinoma cells, but not in thymic tumor cells, or thymic fibroblast cells.

Conclusions

The expression of TS, OPRT and DPD was closely related to the grade of malignancy in thymic epithelial tumors. A positive expression of TS, DPD and OPRT might be an important factor in predicting the effectiveness of 5-FU based chemotherapy in this disease.     

MicroRNA-143 is a putative predictive factor for the response to fluoropyrimidine-based chemotherapy in patients with metastatic colorectal cancer

Approximately half of the colorectal cancer (CRC) patients develop metastatic disease. Fluoropyrimidine-based chemotherapy forms the backbone of treatment in these patients. However, the response to this therapy varies between individuals. Therefore, an important challenge in CRC research is to identify biomarkers that are predictive of this response. In this study, we explored the potential of miRNAs, and the miRNA producing protein Dicer, as biomarkers that can predict chemo-sensitivity to fluoropyrimidine chemotherapy in patients with metastatic colorectal cancer (mCRC). We analyzed the levels of 22 miRNAs and the Dicer protein in primary tumors from patients with mCRC who were treated with first-line capecitabine monotherapy within the CAIRO trial of the Dutch Colorectal Cancer Group. Correlation between the expression status of miRNAs or Dicer in primary tumors and the progression free survival (PFS) were investigated. Patients with low expression of miR-143 in their primary tumor had increased median PFS compared to those with high expression of miR-143. Furthermore, FXYD3, an ion transport regulator and a putative target of miR-143, also showed an association with PFS. These findings warrant further studies to investigate the relationship between miR-143, FXYD3 and fluoropyrimidines, and the clinical utility of miR-143 as biomarker.     

Predictive value of thymidylate synthase expression in advanced colorectal cancer patients receiving fluoropyrimidine-based chemotherapy: evidence from 24 studies

The published data about thymidylate synthase (TS) expression and its predictive value in advanced colorectal cancer (CRC) patients receiving fluoropyrimidine-based chemotherapy seemed inconclusive. To derive a more precise estimation of the relationship, a metaanalysis was performed. Studies have been identified by searching PubMed and Embase. Inclusion criteria were advanced CRC patients, received fluoropyrimidine-based chemotherapy and evaluation of TS expression and overall response rate (ORR). The relative ratio (RR) for ORR in patients with low-TS expression over those with high-TS expression with 95% confidence interval (CI) was calculated for each study as an estimation of the predictive effect of TS. A total of 24 studies including 1,112 patients were involved in this metaanalysis. The overall RR was 2.20 (95% CI, 1.82-2.66; p = 0.000). For studies evaluating TS expression in metastatic lesions, the pooled RR was 3.23 (95% CI, 2.27-4.59; p = 0.000); for studies testing TS expression in primary lesions, a pooled RR of 1.89 (95% CI, 1.45-2.48; p = 0.000) was estimated. Focusing the analysis on immunohistochemistry (IHC)-based or RTPCR-based assessments, the pooled RR was 1.83 (95% CI, 1.44-2.34; p = 0.000) and 2.96 (95% CI, 2.07-4.22; p = 0.000), respectively. The results indicated that low-TS expression tumors in advanced CRC patients were more sensitive to fluoropyrimidine-based chemotherapy. Subgroup analyses indicated that the predictive value of TS expression evaluated in metastases was more prominent than that of primary lesions, and that TS expression tested by RTPCR was also of greater predictive value than by IHC.     

Intratumoral expression of thymidylate synthase and dihydropyrimidine dehydrogenase in non-small cell lung cancer patients treated with 5-FU-based chemotherapy

5-fluorouracil (5-FU) has been used widely, including in gastrointestinal cancer, breast cancer, and non-small cell lung cancer (NSCLC), and its efficacy has been reported to be associated with intratumoral expression of thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD). In order to clarify the clinical value of their expression in NSCLC patients treated with 5-FU, we investigated intratumoral expression of TS and DPD immunohistochemically. Of the 68 tumors studied, 40 carcinomas (58. 8%) had high TS expression, and 33 carcinomas (48.5%) had high DPD expression. The 5-year survival rate of the patients with high-TS tumors was significantly lower than that of the patients with low-TS tumors (P=0.0267), and the 5-year survival rate of the patients with high-DPD tumors was significantly lower than that of the patients with low-DPD tumors (P=0.0268). The Cox regression analysis of prognostic variables for NSCLC patients treated with 5-FU demonstrated that the simultaneous evaluation for both TS and DPD expression was found to be a significant indicator of a poor prognosis (P=0.0043). Our results demonstrated that the evaluation of intratumoral TS and DPD activity can be used to accurately predict responsiveness to 5-FU-based chemotherapy in NSCLC patients.     

Clinical significance of dihydropyrimidine dehydrogenase and thymidylate synthase expression in patients with pancreatic cancer

Background

Little is known about the clinical significance of TS and DPD in pancreatic cancer. We aimed to evaluate TS and DPD expression levels in not only pancreatic cancer but also surrounding normal pancreatic tissues to assess the clinical implications of the expression of TS and DPD in this study.

Patients and methods

Pancreatic cancer and normal pancreatic tissues were obtained from 18 patients with pancreatic cancer who underwent pancreatic resection to measure TS and DPD activities. The TS and DPD activities were determined by enzyme-linked immunosorbent assay using non-fixed fresh-frozen specimens.

Results

Pancreatic cancer tissues had significantly higher DPD and TS enzyme activities than surrounding normal tissue. Anaplastic ductal carcinoma had higher DPD and TS activities than the other histological types. Patients with high DPD in this study demonstrated poorer prognosis than those with low DPD. On the other hand, there was no statistically significant difference in survival between the high and the low TS groups.

Conclusions

The efficacy of 5-FU may be lower in pancreatic cancer tissue than in normal tissue because DPD activity is upregulated in pancreatic cancer tissue compared to normal pancreatic tissue. It is necessary to develop an effective 5-FU delivery system and/or 5-FU combined with an inhibitor for DPD that can be used when 5-FU must be administered to patients with pancreatic cancer. High DPD activity may be a prognostic factor in patients with pancreatic cancer.     

Prognostic significance of thymidylate synthase, dihydropyrimidine dehydrogenase and thymidine phosphorylase protein expression in colorectal cancer patients treated with or without 5-fluorouracil-based chemotherapy

Background: Low tumour expression levels of thymidylate synthase(TS), dihydropyrimidine dehydrogenase (DPD) and thymidine phosphorylase(TP) have been linked with improved outcome for colorectal cancer(CRC) patients treated with 5-fluorouracil (5-FU). It is unclearwhether this occurs because such tumours have better prognosisor they are more sensitive to 5-FU treatment. Patients and methods: Associations between TS, DPD and TP levels,determined by tissue microarrays and immunohistochemistry, andsurvival was evaluated in 945 CRC patients according to treatmentstatus. Results: Low TS and DPD expression associated with worse prognosisin stage II [hazard ratio (HR) = 1.69, 95% confidence interval(CI) (1.09–2.63) and HR = 1.92 (95% CI 1.23–2.94),respectively] and stage III CRC patients treated by surgeryalone [HR = 1.39 (95% CI 0.92–2.13) and HR = 1.49 (95%CI 1.02–2.17), respectively]. Low TS, DPD and TP associatedwith trends for better outcome in stage III patients treatedwith 5-FU [HR = 0.81 (95% CI 0.49–1.33), HR = 0.70 (95%CI 0.42–1.15) and HR = 0.66 (95% CI 0.39–1.12),respectively]. Conclusion: Low TS and DPD expression are prognostic for worseoutcome in CRC patients treated by surgery alone, whereas lowTS, DPD and TP expression are prognostic for better outcomein patients treated with 5-FU chemotherapy. These results provideindirect evidence that low TS, DPD and TP protein expressionare predictive of good response to 5-FU chemotherapy. Key words: colorectal cancer, fluorouracil, predictive, prognostic, thymidylate synthase Received for publication July 12, 2007. Revision received December 10, 2007. Accepted for publication December 17, 2007.     

Liver-only metastatic colorectal cancer patients and thymidylate synthase polymorphisms for predicting response to 5-fluorouracil-based chemotherapy

We investigated the association between thymidylate synthase (TS) germline polymorphisms and response to 5-fluorouracil-based chemotherapy in 80 patients with liver-only metastatic colorectal cancer (MCRC). The tandem repeat polymorphism (VNTR) in TS 5'-untranslated region (5'-UTR), which consists of two (2R) or three (3R) 28-bp repeated sequences, with or without a G/C nucleotide change in 3R carriers (3G or 3C) and a 6-bp insertion/deletion (6+/6-) in the TS 3'-UTR, was studied. The distinction between high (2R/3G, 3C/3G and 3G/3G) and low (2R/2R, 2R/3C and 3C/3C) TS expression genotypes according to the 5'-UTR VNTR+G/C nucleotide change showed significant association with tumour response (P=0.01). In particular, high TS expression genotypes were found in 8 out of 34 patients (23.5%) with complete or partial response and in 24 out of 46 patients (52%) with stable disease and disease progression. Liver-only MCRC patients are a homogeneous and clinical relevant subgroup that may represent an ideal setting for studying the actual influence of TS polymorphisms.     

Thymidylate synthase gene expression in primary colorectal cancer and metastatic sites

No Abstract     

The prognostic significance of thymidylate synthase and dihydropyrimidine dehydrogenase in colorectal cancer of 303 patients adjuvantly treated with 5-fluorouracil

Cytotoxic effect of 5-fluorouracil 5-FU is mediated through inhibition of thymidylate synthase (TS), and 5-FU is catabolised by dihydropyrimidine dehydrogenase (DPD). Efficacy of 5-FU may therefore depend on the TS and DPD activity of colorectal cancer. Archival tumour specimens from 303 consecutive patients were analysed for the expression of TS and DPD using immunohistochemistry. All patients were completely resected for colorectal cancer stages II-III and have subsequently received adjuvant treatment with 5-FU. In a multivariate analysis adjusting for the impact of bowel obstruction and vascular tumour invasion, diffuse TS pattern was significantly associated with increased risk of recurrence (hazard ratio (HR) = 1.9; 95% confidence interval (CI): 1.1-3.2; p = 0.02), but without significant association to death (HR = 1.6; 95% CI: 0.9-2.8; p = 0.08). High TS intensity was not significantly associated with lower risk of recurrence (HR = 0.6; 95% CI: 0.3-1.1; p = 0.07) or death (HR = 0.6; 95% CI: 0.3-1.2; p = 0.2). High DPD intensity was significantly associated with increased risk of recurrence (HR = 1.5; 95% CI: 1.1-2.3; p = 0.03) and death (HR = 1.6; 95% CI: 1.1-2.5; p = 0.02). Patients with a combination of low TS and high DPD intensity were at significantly increased risk of both recurrence (HR = 2.1; 95% CI: 1.0-4.2; p = 0.04) and death (HR = 2.0; 95% CI: 1.0-4.0; p = 0.05). No relationship between tolerability and toxicity of 5-FU and TS and DPD expression was found. It is concluded that characterizing colorectal carcinomas by TS and DPD expression may disclose subsets of patients with significantly greater risk of disease recurrence and early death. This may be utilized in the selection of patients for treatment approaches and for decision on follow-up programs.     

Predictive role of thymidylate synthase, dihydropyrimidine dehydrogenase and thymidine phosphorylase expression in colorectal cancer patients receiving adjuvant 5-fluorouracil

OBJECTIVE: The combined assessment of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD) and thymidine phosphorylase (TP) gene expressions in metastatic colorectal cancer has been reported to be able to predict the efficacy of fluoropyrimidine-based chemotherapy. In order to evaluate the prognostic role in the adjuvant setting, we investigated the TS, DPD and TP expression in primary tumors of colorectal cancer patients treated with 5-fluorouracil (5-FU). METHODS: TS, DPD and TP expression levels were determined by immunohistochemistry in paraffin-embedded primary tumor tissues from 62 patients with Dukes' stage B and C colorectal cancers who underwent surgery and received adjuvant systemic chemotherapy with 5-FU. The median follow-up was 90 months (range 17-127). RESULTS: Dukes' stage C cancer and high TS expression were independent markers of poor prognosis for disease-free survival (DFS; p = 0.0009 and p = 0.007, respectively) and overall survival (OS; p = 0.0005 and p = 0.011, respectively). By multivariate analysis, patients with high DPD expression had significantly shorter DFS (p = 0.007) and OS (p = 0.005) compared to patients with low DPD expression. In the combined analysis of 2 markers, patients with low TS and low DPD had the best outcome in terms of DFS (p = 0.007) and OS (p = 0.03). The analysis of all 3 proteins showed that the patients with low expression of all 3 markers had significantly longer DFS (p = 0.04) and OS (p = 0.01) than patients with a high value of any one of the protein expressions. However, the joint analysis of 3 markers (group with TS-/DPD-/TP-) could not identify a subgroup of patients with a better prognosis compared to the analysis of 2 markers (group with TS-/DPD-). The analysis of Dukes' stage C cancer patients confirmed a significant benefit in terms of DFS and OS (p = 0.001 and p = 0.006, respectively) when all 3 markers had low expression. We also found a positive significant correlation between TS and TP protein expression (p = 0.033). CONCLUSIONS: This retrospective investigation suggests that the combined assessment of TS and DPD may be useful to evaluate the prognosis of patients with Dukes' B and C colon carcinoma receiving 5-FU adjuvant chemotherapy. The role of TP as a predictor for 5-FU-based therapy needs further investigations.