Genomic profiling associated with recurrence in patients with rectal cancer treated with chemoradiation.

PURPOSE: Stage II and III adenocarcinoma of the rectum has an overall 5-year survival rate of approximately 50%, and tumor recurrence remains a major problem despite an improvement in local control through chemotherapy and radiation. The efficacy of chemoradiation therapy may be significantly compromised as a result of interindividual variations in clinical response and host toxicity. Therefore, it is imperative to identify those patients who will benefit from chemoradiation therapy and those who will develop recurrent disease. In this study, we tested whether a specific pattern of 21 polymorphisms in 18 genes involved in the critical pathways of cancer progression (i.e., drug metabolism, tumor microenvironment, cell cycle regulation, and DNA repair) will predict the risk of tumor recurrence in rectal cancer patients treated with chemoradiation. PATIENTS AND METHODS: A total of 90 patients with Stage II or III rectal cancer treated with chemoradiation were genotyped using polymerase chain reaction (PCR)-based techniques for 21 polymorphisms. RESULTS: A polymorphism in interleukin (IL)-8 was individually associated with risk of recurrence. Classification and regression tree analysis of all polymorphisms and clinical variables developed a risk tree including the following variables: node status, IL-8, intracellular adhesion molecule-1, transforming growth factor-beta, and fibroblast growth factor receptor 4. CONCLUSION: Genomic profiling may help to identify patients who are at high risk for developing tumor recurrence, and those who are more likely to benefit from chemoradiation therapy. A larger prospective study is needed to validate these preliminary data using germline polymorphisms on tumor recurrences in rectal cancer patients treated with chemoradiation.

Structural determination of saponins extracted from starfish by fast atom bombardment collision-induced dissociation mass spectrometry.

Three saponins were extracted and isolated from starfish by reversed-phase high performance liquid chromatography (HPLC), and analyzed by fast atom bombardment mass spectrometry (FAB-MS). Their molecular weight information could be obtained by the presence of abundant [M+Na]+ ions and weak [M+H]+ ions in FAB-MS spectra. Moreover, high resolution mass measurements of their [M+Na]+ ions were performed at the resolution of 10000 to elucidate the element composition of extracted saponins. The collision-induced dissociation (CID) of sodium-adducted molecules [M+Na]+ yielded diverse product ions via dissociated processes. In the collision-induced dissociation (CID)-MS/MS analysis of [M+Na]+ ion, the sulfate-containing saponins produced characteristic ions such as SO4Na+, [NaHSO4+Na]+, [M+Na-sugar]+ and [M+Na-2sugar]+ ions, whereas the sulfate-free compound showed characteristic ions produced by cleavage of sugar moiety and side chain of aglycone. The fragmentation patterns could provide information on the linkage position of sugar groups in aglycone and sulfate groups.

Gene polymorphisms of epidermal growth factor receptor and its downstream effector, interleukin-8, predict oxaliplatin efficacy in patients with advanced colorectal cancer.

BACKGROUND: Researchers have recently reported an association between the epidermal growth factor receptor (EGFR) pathway and platinum-chemotherapy sensitivity in cancer patients. The (CA)(n) repeat polymorphism in intron 1 of the EGFR gene has been identified and found to alter EGFR expression in vitro as well as in vivo. A higher number of these CA repeats is associated with lower EGFR levels, whereas a low number of repeats is associated with higher EGFR levels. A second key polymorphism within the EGFR pathway (HER1 R497K) is a single nucleotide change (G-A) in codon 497 of the EGFR gene, which leads to an arginine-lysine substitution in the extracellular domain of subdomain IV. Furthermore, interleukin-8 (IL-8), recently identified as an EGFR downstream effector, plays a vital role in tumor angiogenesis and progression. Three other polymorphisms, each related to the IL-8 gene, have also been identified as playing a pivotal role in the EGFR pathway: T-251A in the promoter region of the IL-8 gene, G+2607C in exon 2 of the IL-8 receptor CXCR1 gene, and C+785T in exon 11 of the IL-8 receptor CXCR2 gene. PATIENTS AND METHODS: In this study, we employed a 5'-end 33P-gATP-labeled polymerase chain reaction (PCR) protocol as well as the PCR-restriction fragment length polymorphism method in order to determine the genotypes for the previously mentioned polymorphisms in 105 patients with metastatic colorectal cancer. Tests were conducted to establish whether these polymorphisms could predict clinical outcome to 5-flourouracil/oxaliplatin chemotherapy. RESULTS: Among all patients assessed, those possessing < 20 EGFR CA repeats were more likely to show disease progression than were patients with >or= 20 CA repeats (P = 0.019; log-rank test). Also, patients with the CXCR1 GC genotype were found to have an increased relative risk of time to tumor progression that was 1.55 (95% CI, 0.8-3.0) times that of patients with the homozygous GG genotype (P = 0.17; log-rank test). CONCLUSION: Overall, our data suggest that gene polymorphisms active in the EGFR pathway may be associated with the sensitivity of colorectal cancer patients to platinum-based chemotherapy.

ERCC1 gene polymorphism as a predictor for clinical outcome in advanced colorectal cancer patients treated with platinum-based chemotherapy.

Excision repair cross-complementation group 1 (ERCC1) is a highly conserved protein and an essential member of the nucleotide excision repair pathway. DNA repair is an important mechanism for resistance to platinum-based chemotherapy. Previous studies have shown that ERCC1 gene expression is associated with clinical outcome to platinum chemotherapy in a variety of cancers. Recently, 2 common polymorphisms in the ERCC1 gene have been described. The first is a single nucleotide polymorphism at codon 188 of the ERCC1 gene that causes a C-->T change but codes for the same amino acid, asparagine. This polymorphism may be associated with differential ERCC1 gene expression. The second is also a signal nucleotide polymorphism in the 3'-untranslated region and may affect MRNA stability. We hypothesized that these 2 polymorphisms may be associated with clinical outcome to platinum-based chemotherapy. We assessed the relationship between these ERCC1 gene polymorphism and clinical outcome to platinum-based chemotherapy in 106 patients with advanced refractory colorectal cancer. We found a significant associated between the ERCC1 codon 118 polymorphism and clinical outcome. Patients with the C/C genotype had a median survival of 15.3 months (95% CI, 6.0-12.1) and 11.1 months (95% CI, 5.8-16.2) for those with C/T and T/T genotypes, respectively. The ERCC1 codon 118 polymorphism may be a useful predictor of clinical outcome in advanced colorectal cancer patients treated with platinum-based chemotherapy.

Structural determination of monoacylglycerols extracted from marine sponge by fast atom bombardment tandem mass spectrometry.

Five new monoacylglycerols (MAGs) were isolated from the marine sponge Stelletta sp. by reversed-phase high-performance liquid chromatography and analyzed by positive ion fast atom bombardment mass spectrometry (FAB-MS). FAB mass spectra of these compounds produced abundant sodium-adducted molecules [M+Na]+ from a mixture of 3-nitrobenzyl alcohol and sodium iodide. The structural elucidation of these sponge MAGs was carried out by FAB tandem mass spectrometry (MS/MS). To find diagnostic ions for the characterization of the MAGs, authentic MAGs were initially analyzed by collision-induced dissociation (CID) MS/MS. The CID MS/MS of [M+Na]+ precursor ions resulted in the formation of numerous characteristic product ions via a series of dissociative processes. The product ions formed by charge-remote fragmentation (CRF) provided important information for the characterization of acyl chains substituted at the glycerol backbone, and product ions at m/z 84, 97, 113 and 139 were diagnostic for the sodiated glycerol backbone. On the basis of these fragmentation patterns, the structures of five MAGs extracted from marine sponge were elucidated. In addition, high-resolution mass measurement was performed to obtain the elemental compositions of the MAGs.

Structural determination of cyclitol derivatives by fast-atom bombardment tandem mass spectrometry.

Three cyclitol derivatives were isolated from the marine sponge Sarcotragus sp. by reversed-phase high-performance liquid chromatography and analyzed by fast-atom bombardment mass spectrometry (FAB-MS). Their structural elucidation was carried out with FAB tandem mass spectrometry (FAB-MS/MS). FAB-MS spectra produced a significant abundance of the sodium adducts [M+Na]+ and [M+2Na-H]+ from a mixture of m-NBA and NaI. In addition, trifluoroacetylation of the cyclitol derivatives was used for confirmation of the presence of the cyclitol ring. High abundance [M-5H+5CF3CO+Na]+ ions were observed in the FAB-MS spectra of the trifluoroacetyl-cyclitol derivatives. Collision-induced dissociation (CID) of the [M+Na]+ ions produced diverse product ions via a series of dissociative processes. Charge-remote fragmentation (CRF) patterns of [M+Na]+ ions were very useful for the identification of product ions which are characteristic for the cyclitol ring and long hydrocarbon chains substituted at the glycerol backbone. Moreover, the CID-MS/MS spectra of the [M+Na]+ ions yielded characteristic product ions at m/z 53, 83, 113, 155 and 171 for the cyclitol moiety, and at m/z 213, 229 and 245 for the glycerol backbone attached to the cyclitol ring.

Structural determination of hexadecanoic lysophosphatidylcholine regioisomers by fast atom bombardment tandem mass spectrometry.

The structural determination of sn-1 and sn-2 hexadecanoic lysophosphatidylcholine (LPC) regioisomers was carried out using fast atom bombardment tandem mass spectrometry (FAB-MS/MS). The collision-induced dissociation (CID) of protonated and sodiated molecules produced diverse product ions due mainly to charge remote fragmentations. Based on the information obtained from the CID spectra of protonated and sodiated molecules, sn-1 and sn-2 hexadecanoic LPC isomers could be discriminated. Especially, the abundance ratio of the diagnostic ion pair [m/z 224/226] in the CID spectra of [M + H](+) ions was shown to be greatly different. Moreover, the CID-MS/MS spectra of sodium-adducted molecules for hexadecanoic LPC isomers showed characteristic product ions such as [M + Na - 103](+), [M + Na - 85](+), and [M + Na - 59](+), by which their regio-specificity can be differentiated.

Expression of the serine protease matriptase and its inhibitor HAI-1 in epithelial ovarian cancer / 대한산부인과학회지

OBJECTIVE: The purposes of this study were to examine the expression of matriptase, and its inhibitor, HAI-1, in epithelial ovarian cancer and to assign clinicopathological correlations and to discuss the matriptase/inhibitor (HAI-1) system in the context of ovarian cancer and to examine the possibility that this system might be a useful therapeutic target in this disease. METHODS: A retrospective study was performed in 51 patients with primary epithelial ovarian cancer staged over Ic who have been diagnosed and treated at Kyung Hee university medical center from Jan. 1991 to Mar. 2003. They were managed with cytoreductive surgery and chemotherapy. This study was performed in paraffin embedded blocks of primary epithelial ovarian cancer of 51 patients by means of immunohistochemistry. In addition, to validate protein expression data at the gene level, matriptase/HAI-1 mRNA expression was evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) on frozen specimens from 10 ovarian cancers. Statistical analyses of immunohistochemistry (IHC) expression data with clinicopathological parameters and survival were then performed. RESULTS: Of 51 ovarian tumors tested, 25 (49%) and 37 (72.5%) were positive staining for matriptase and HAI-1 by IHC, respectively. Of 18 stage I/II tumors, 11 (61.1%) stained positive for matriptase, and 15 (83.3%) stained positive for HAI-1; Of 18 stage I/II tumors, 10 (55.6%) tumors showed coexpression. Of 33 stage III/IV tumors, 14 (42.4%) stained positive for matriptase and 22 (66.7%) stained positive for HAI-1; Of 33 stage III/IV tumors, 11 (33.3%) tumors showed coexpression. CONCLUSION: No relationship was found between the expression of either matriptase or HAI-1 with clinicopathological parameters and survival. However, stage I/II ovarian tumors are more likely to express matriptase and HAI-1 than are the more advanced disease stage III/IV tumors. Correspondingly, the low frequency of matriptase and HAI-1 coexpression is more likely to be associated with stage III/IV tumors than stage I/II tumors. Such an imbalance in the matriptase: HAI-1 ratio could promote the proteolytic activity of matriptase and, consequently, a more invasive phenotype in the advanced tumors.

Abnormal Fragile Histidine Triad (FHIT) Expression in Cervical Carcinomas / 대한산부인과학회잡지

OBJECTIVE: The fragile histidine triad (FHIT) gene is located at chromosome 3p14.2 and encompasses the common fragile site, FRA3B, which may contribute to chromosome breakage and rearrangement of cancer cells. In this study, we examined whether transcriptional alterations of FHIT gene play a role in the development of human cervical carcinomas and the possibility that hypermethylation of CpG islands serves for FHIT inactivation. We then analyzed FHIT expression status with clinical parameters to determine whether it has any prognostic significance. METHODS: The study group included 50 squamous carcinomas, 4 adenocarcinomas, 4 adenosquamous carcinomas, 7 noncancerous tissue and the clinical stage is composed of 4 Ia, 37 Ib and 17 II. Tissue specimens were snap-frozen in liquid N2 and stored at -70degrees C until used. To examine for abnormal transcripts of the FHIT gene, quantitative RT-PCR, genomic DNA-PCR and nonisotopic RT-PCR-SSCP analysis were performed using the standard method. The methylation status was determined by methylation specific PCR. RESULTS: The FHIT gene was down-regulated in 15 of 58 (25.9%) cervical carcinomas. FHIT promoter hypermethylation was detected in 15 of 15 (100%) abnormally expression in cervical carcinomas. CONCLUSION: In this study, gene mutation is not a main mechanism for FHIT inactivation, but the aberrant promoter hypermethylation may be correlated with decreased expression of the FHIT gene. The significance of decreased expression of FHIT does not appear to be an independent prognostic factor in cervical cancers, although a still larger sample of patients will be required to asses this issue definitively.

Correlation of Telomerase Activity, hTERT mRNA Expression and HPV E6 Detection in Cervical Cancer Tissue / 대한산부인과학회잡지

OBJECTIVE: Telomerase is a ribonucleoprotein enzyme which stabilizes chromosomal structure, thereby inducing cellular immortality. We investigated telomerase activity and human telomerase reverse transcriptase (hTERT) mRNA expression in relation to high-risk human papillomavirus (HPV) DNA presence in cervical carcinomas. METHODS: From December 1995 to December 1999, at the department of obstetrics and Gynecology of Kyung-Hee University Hospital, 32 cervical carcinomas and 5 corresponding nontumor cervical tissues were obtained and the samples were immediately frozen and stored at -70 degree C. Telomerase activity was measured by using telomerase PCR ELISA, a modified version of the TRAP. Analysis of the expression of hTERT mRNA was performed by quantitative RT-PCR and the analysis of the HPV E6 gene was performed by DNA-PCR. RESULT: All of the carcinomas examined exhibited strongly positive for telomerase activity (OD>0.24), whereas telomerase activity was week or not found in the 5 corresponding nontumor cervical tissues. Quantitative RT-PCR analysis demonstrated significantly increased hTERT mRNA expression levels (>0.024) in most carcinomas comparing to control groups. There was no obvious relationship between telomerase activity levels and the clinical parameters examined including age, clinical stage, pathology, differentiation, tumour size, LN involvement and invasion depth except lymphovascular space invasion (p=0.03). In the correlation between the levels of hTERT mRNA expression and telomerase activity, correlation index which was 0.916, shows high correlation (p=0.01). According to the analysis of HPV E6 gene, 29 of 32 (90.6%) carcinomas showed HPV E6 positivity. CONCLUSION: There is a strong association between telomerase activity and hTERT mRNA expression, and up-regulation of hTERT probably plays a role in the progression of cervical carcinomas. Telomerase is at least partially activated by viral oncogenes of high-risk types. There is no obvious relationship between telomerase activity levels and the clinical parameters except LSVI (p=0.03). These findings provides that telomerase may play an important role in the early stage of carcinogenesis.