The aim of our present study is to find the influence of DPYD*9A, DPYD*6 and GSTP1 ile105val gene polymorphisms on CAPOX treatment-associated toxicities in south Indian patients with CRC.
Immunohistochemical localization of 5-FU metabolic enzymes (TS, MTHFR, DPYD, and TP) was evaluated in 143 untreated patients with colorectal cancer; their prognostic and predictive values were also evaluated.
We analysed more than 200 potentially functional, common, inherited variants in genes within the 5FU, capecitabine, oxaliplatin and DNA repair pathways, together with four rare dihydropyrimidine dehydrogenase (DPYD) variants, in 2183 aCRC patients treated with oxaliplatin-fluoropyrimidine chemotherapy with, or without, cetuximab (from MRC COIN and COIN-B trials).
Value of plasma SN-38 levels and DPD activity in irinotecan-based individualized chemotherapy for advanced colorectal cancer with heterozygous type UGT1A1<sup>*</sup>6 or UGT1A1<sup>*</sup>28.
Analyses of KRAS mutations in metastatic colorectal cancer, EGFR mutations in advanced non-small cell lung cancer, CYP2D6 polymorphism in breast cancer, DPD polymorphism in colorectal cancer and MTHFR polymorphism in osteosarcoma have been performed by real time polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP).
The polymorphism c.496A>G was the DPYD gene variant with the highest detection rate (12.9%), occurred predominantly in females (86.7%, p=0.0044) and was exclusively seen in KRAS wild type primary CRC (15/65 (23.1%) vs 0/51 (0%) in KRAS-mutated primary CRC, respectively, p=0.0001).
In this study, primary tumors obtained from 1,129 patients with colorectal cancer were used to measure the mRNA expression levels of the following genes associated with the effects of standard chemotherapy for colorectal cancer: 5-fluorouracil (5-FU)-related thymidylate synthase (TYMS), dihydropyrimidine dehydrogenase (DPYD) and thymidine phosphorylase (TYMP); folate-related dihydrofolate reductase (DHFR), folylpolyglutamate synthase (FPGS) and gamma-glutamyl hydrolase (GGH); irinotecan-related topoisomerase I (TOP1); oxaliplatin-related excision repair cross-complementing 1 (ERCC1); biologic agent-related vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR).
A candidate gene study of capecitabine-related toxicity in colorectal cancer identifies new toxicity variants at DPYD and a putative role for ENOSF1 rather than TYMS.
Our previous study showed that administering oxaliplatin as first-line chemotherapy increased ERCC1 and DPD levels in liver colorectal cancers (CRCs) metastases.
The studies we reviewed indicate that pharmacogenetic testing is promising to direct personalised dosing of fluoropyrimidines, although further investigations are needed to establish the role of DPD in severe toxicity in patients treated for colorectal cancer.
No association was observed between DPYD aberrations and patient survival, suggesting that assessment of somatic DPYD intragenic rearrangement status is not a powerful biomarker to predict the outcome of 5FU-based chemotherapy in patients with colorectal cancer.
Messenger RNA (mRNA) expression of major 5-FU metabolic enzymes, namely thymidylate synthase, dihydropyrimidine dehydrogenase, thymidine phosphorylase (TP), orotate phosphoribosyl transferase, and β-actin (control) was evaluated using the Danenberg Tumor Profile method. mRNA expression and other clinicopathological data were investigated with regard to CRC relapse.
Danenberg tumor profile method (DTP) was used in order to measure mRNA expression levels of thymidylate synthase (TYMS), dihydropyrimidine dehydrogenase (DPYD), and thymidine phosphorylase (TYMP) from 180 patients with colorectal cancer.
This review summarizes the current knowledge about the splice isoforms of VEGFA, UGT1A, PXR, cyclin D1, BIRC5 (survivin), DPD, K-RAS, SOX9, SLC39A14 and other genes, which may be possible therapeutic targets for colorectal cancer.
The DPYD(*)2A allele was identified only in one patient: a male who was one of 4 CRC patients suffering from grades 3-4 myelotoxicity upon 5-FU chemotherapy.
MSI in five reference loci, MMR enzymes (hMSH2, hMSH6, hMLH1 and hPMS2), thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) expression were assessed in paraffin embedded tumor specimens, and associated with outcome in 340 consecutive patients completely resected for colorectal cancer stages II-IV and subsequently receiving adjuvant 5-fluorouracil therapy.
The expression ratios to beta-actin of mRNA of thymidine synthase (TS), dihydropyrimidine dehydrogenase (DPD), thymidine phosphorylase (TP) and oroteta phosphoribosyl transferase (OPRT) were measured in primary and liver metastases of colorectal carcinomas by laser-captured microdissection and real time PCR.