Association of cytochrome P450 2C9 polymorphism with locally advanced head and neck squamous cell carcinoma and response to concurrent cisplatin-based radical chemoradiation

CYP2 C9 polymorphism among patients with oral squamous cell carcinoma and its role in altering the metabolism of benzo[a]pyrene

OBJECTIVES

The aim of this study was to evaluate the prevalence of CYP2 C9 polymorphism among healthy controls and patients with oral squamous cell carcinoma (OSCC) and to analyze the risk of disease development. We also investigated the interaction between CYP2 C9 wild type and the polymorphic variants with benzo[a]pyrene by using molecular docking analysis.

STUDY DESIGN

The study included 46 patients with OSCC and 46 controls. Amplification of the genomic DNA was done by using allele-specific polymerase chain reaction and then analyzed by using agarose gel electrophoresis. Molecular docking was then carried out to determine the interaction of CYP2 C9*1, CYP2 C9*2, and CYP2 C9*3 with benzo[a]pyrene.

RESULTS

In the OSCC group, CYP2 C9*2 and CYP2 C9*3 polymorphisms were 17.4% and 15.2%, respectively, and in the control group, they were 8.7% and 6.5%, respectively. The OSCC group showed a statistically significant (P = .043) increase in the prevalence of CYP2 C9 polymorphic variants compared with the control group. The docking analysis showed benzo[a]pyrene to bind specifically to the altered single nucleotide catalytic site in the polymorphic CYP2 C9*3 enzyme.

CONCLUSIONS

This study demonstrates that functionally important CYP2 C9 polymorphism exists among patients with OSCC, with a modest increase in the risk of disease development in those individuals who acquire these poor metabolizing variants. The modified docking of CYP2 C9*3 with benzo[a]pyrene signifies altered metabolism in vivo.

CYP Genotypes Are Associated with Toxicity and Survival in Osteosarcoma Patients

Purpose: Osteosarcoma is the malignant bone tumor most common in children and adolescents. Many cytochrome P-450 (CYP) members detoxify anticancer drugs used in osteosarcoma treatment, and thus, the aim of the present study was to investigate CYP polymorphisms in osteosarcoma patients. Methods: The present study investigated DNA from peripheral blood from 70 osteosarcoma patients treated with high doses of cisplatin, doxorubicin, and methotrexate. CYP1A2*1F (163C>A; rs762551); CYP2C9*3 (1075A>C; rs1057910); and CYP3A5*3 (6986A>G; rs776746) polymorphisms were investigated through real-time PCR using TaqMan probes. Results: The CYP2C9*3 allele did not present any association with clinical events. The CYP1A2 CC/AC genotypes were associated with ototoxicity occurrence (p = 0.041, odds ratio [OR] = 8.4) and high grades of ototoxicity (p = 0.039, OR = 10.7), when compared with patients carrying the CYP1A2 AA genotype. The CYP1A2 CC genotype was associated with high grades of diarrhea (p = 0.043, OR = 4.6) and fever (p = 0.041, OR = 7.1) in comparison with the CYP1A2 AA/AC genotypes. The CYP3A5 CC genotype was associated with weight loss (p = 0.009, OR = 3.8) and high grades of hepatotoxicity (p = 0.010, OR = 4.3) when compared with the CYP3A5 TT/CT genotypes. The CYP3A5 CC/CT genotypes were associated with high grades of vomit (p = 0.013, OR = 10.8), pulmonary relapse absence (p = 0.029, OR = 9.5), and better overall and event-free survivals (p = 0.017, hazard ratio [HR] = 3.1; p = 0.044, HR = 2.5; respectively) when compared with the CYP3A5 AA genotype. Conclusion: CYP1A2*1A and CYP3A5*3 alleles were associated with toxicity events. CYP3A5*3 allele was associated with better survival. Thus, CYP genotypes might be promising markers to tailoring treatment in osteosarcoma patients.

Dynamic contrast-enhanced MRI evaluates the early response of human head and neck tumor xenografts following anti-EMMPRIN therapy with cisplatin or irradiation

PURPOSE

To assess the early therapeutic effects of anti-EMMPRIN (extracellular matrix metalloprotease inducer) antibody with/without cisplatin or X-ray radiation in head and neck cancer mouse models using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

MATERIALS AND METHODS

Mice bearing SCC1 (or OSC19) tumor xenografts were treated with anti-EMMPRIN antibody, radiation, cisplatin, or anti-EMMPRIN antibody plus cisplatin (or radiation) for a week (n = 4-5 per group). DCE-MRI was carried out on a 9.4T small animal MR scanner on days 0, 3, and 7, and K(trans) values were averaged in a 0.5-mm-thick peripheral tumor region. Ki67 and CD31 staining were implemented for all tumors after imaging.

RESULTS

The K(trans) changes of SCC1 and OSC19 tumors treated with anti-EMMPRIN antibody for 3 days were -18 ± 8% and 4 ± 7%, respectively, which were significantly lower than those of control groups (39 ± 5% and 45 ± 7%; P = 0.0025 and 0.0220, respectively). When cisplatin was added, those were -42 ± 9% and -44 ± 9%, respectively, and with radiation, -45 ± 9% and -27 ± 10%, respectively, which were also significantly lower than those of control groups (P < 0.0001 for all four comparisons). In the eight groups untreated (served as control) or treated with anti-EMMPRIN antibody with/without cisplatin or radiation, the mean K(trans) change for 3 days was significantly correlated with the mean tumor volume change for 7 days (r = 0.74, P = 0.0346), Ki67-expressing cell density (r = 0.96, P = 0.0001), and CD31 density (r = 0.84, P = 0.0084).

CONCLUSION

DCE-MRI might be utilized to assess the early therapeutic effects of anti-EMMPRIN antibody with/without chemotherapy or radiotherapy in head and neck cancer.