Association of nasopharyngeal carcinoma risk with cytochrome P450 CYP1A1 gene polymorphisms / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the association between CYP1A1 gene polymorphisms and susceptibility of nasopharyngeal carcinoma in Cantonese nuclear families through family-based association study.</p><p><b>METHODS</b>A total of 457 Cantonese nuclear families,consisting of 2134 members, were recruited as subjects. Each family included two parents and at least one offspring with nasopharyngeal carcinoma. Two single nucleotide polymorphisms (SNP) in CYP1A1 named m1 (rs4646903) and m2 (rs1048943), were genotyped by PCR-RFLP assay and verified by directly sequencing. The genotype data were analyzed with family-based association test (FBAT) software to check the linkage and association between the two genetic markers and susceptibility of nasopharyngeal carcinoma.</p><p><b>RESULTS</b>FBAT analysis showed that the minor allele frequencies (MAF) of the two SNP were 0.442 (C) and 0.339 (G) respectively. For m1 polymorphism in CYP1A1 gene was not significantly associated with nasopharyngeal carcinoma in our study population whether stratified with VCA-IgA or not (without stratification: chi2 = 2.399, P = 0.301; with stratification: low-titer group (VCA-IgA <1:80), MAF = 0.457 (C), chi2 = 1.221, P = 0.543; high-titer group (VCA-IgA > or = 1:80), MAF = 0.427 (C), chi2 =2.832, P = 0.243) . For m2 polymorphism, when VCA-IgA <1:80, the G allele showed decreased transmission under additive and dominant model (MAF = 0.347 (G); Zadditive = -2.120, Padditive = 0.034; Zdominant = - 2.303, Pdominant = 0.021) and a boundary P value was got with global statistic (chi2 = 5.394, P = 0.067) . Haplotype TG (0.057), constructed by m1 and m2, might decrease nasopharyngeal carcinoma risk (Z= -2.002, P=0.045). A boundary P value was also got with global statistic (chi2 =7.067, P=0.070).</p><p><b>CONCLUSION</b>There was no statistical significance between m1 polymorphism and susceptibility of nasopharyngeal carcinoma in Cantonese nuclear families. And this study showed that m2 polymorphism might associated with the decrease of nasopharyngeal carcinoma in Cantonese nuclear families.</p>

FTIR spectroscopic explorations of freshly resected laryngeal carcinoma tissues / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the characteristics of freshly resected laryngeal carcinoma by Fourier transform infrared spectroscopy (FTIR).</p><p><b>METHODS</b>FTIR was applied to the study of the cancerous tissues and adjacent normal tissues in 32 patients.</p><p><b>RESULTS</b>Compared with pathological diagnosis results, one benign specimen was classified as a malignant, the accuracy was 98.4%. Significant differences were seen in the FTIR spectra between the normal and malignant laryngeal tissues. The peak at 1085 cm(-1) shift to 1114 cm(-1) showed that the relative contents of DNA in laryngeal carcinoma cells was increased. The peak at 1397 cm(-1) was stronger than 1451 cm(-1) in normal tissues, while it was not obvious in cancer tissues. I(2926)/I(2870) in carcinoma cells was lower than that in normal tissues. The wave numbers of the bands of amide I and amide II, symmetric and asymmetric stretching bands of CH(3), stretching vibration bands of C-OH and NH band were shifted to higher number in cancer tissues.</p><p><b>CONCLUSION</b>The study shows that the malignant and normal laryngeal tissues have different FTIR spectra, which are mainly due to changes in protein, nucleic acid and phospholipids. FTIR may become a new method for the diagnosis of laryngeal carcinoma in clinical practice.</p>

Family-based association study of XRCC1 gene polymorphisms in nasopharyngeal carcinoma / 中华预防医学杂志

<p><b>OBJECTIVE</b>To test the association between XRCC1 gene polymorphisms and susceptibility of nasopharyngeal carcinoma in Cantonese nuclear families through a family-based association study.</p><p><b>METHODS</b>A total of 2134 study subjects from 457 Cantonese nuclear families were recruited in the study. Each family had two parents and at least one offspring with nasopharyngeal carcinoma. Genotyping for three single nucleotide polymorphisms in XRCC1 gene, including rs1799782 (C > T), rs25489 (G > A) and rs25487 (G > A), were performed with PCR-RFLP assay. The genotype data were analyzed with family-based association test (FBAT) software to check linkage and association between the three genetic markers and susceptibility of nasopharyngeal carcinoma.</p><p><b>RESULTS</b>FBAT analysis showed XRCC1 gene genotypes and haplotypes were not significantly associated with nasopharyngeal carcinoma in our study population (rs1799782: chi(2) = 1.006, P = 0.605; rs25489: chi(2) = 0.470, P = 0.790; rs25487: chi(2) = 2.563, P = 0.278; haplotype: chi(2) = 3.004, P = 0.557, global statistic). For rs25487, the G allele (major allele) showed increased transmission under dominant model (Z = 1.985, P = 0.047). Whereas the C allele (minor allele) exhibited reduced transmission under recessive model (Z = -1.985, P = 0.047). However, no increased/reduced transmission was observed under additive model and with global statistic.</p><p><b>CONCLUSION</b>There is no evidence of an association between polymorphisms in XRCC1 gene and susceptibility of nasopharyngeal carcinoma in Cantonese nuclear families is observed in this study.</p>