Relationship between TNFA, TNFB and TNFRII gene polymorphisms and outcome after unrelated hematopoietic cell transplantation in a Chinese population

Genomic variants in Fas-mediated apoptosis pathway predict a poor response to Platinum-based Chemotherapy for Chinese Gastric Cancer Patients

Platinum-based adjuvant chemotherapy is very common for gastric cancer (GC) patients, but the chemotherapy sensitivity is very heterogeneous. The genomic variants and the gene-gene interactions involved in Fas-mediated apoptosis pathway including Fas (FAS 1377 G > A and 670 A > G), FasL (FASL 844 C > T) and caspase-8 (CASP8 -652 6N ins > del or I > D), may paly vital roles in the response to platinum-based treatment. In our investigation, 662 stage II-III postoperative GC patients were enrolled between 1998 and 2006. 261 patients accepted platinum-based regimens and the remaining 401 were not. The log rank tests, Kaplan Meier plots, Pearson chi-square tests, Student t-tests and Cox regression analyses were performed. For the chemotherapy cohort, FAS 1377 G > A or FAS 670 A > G variants alone was related with inferior survival, and a greater than additive effect was identified when patients simultaneously carrying FAS 1377 GA and FAS 670 GA genotypes. But the poor response was neutralized when patients simultaneously carrying FASL 844 C > T or CASP8 -652 6N ins > del mutations. Our study suggested that FAS 1377 G > A and FAS 670 A > G variants may serve as potential biomarkers to predict the response to platinum-based adjuvant chemotherapy, and the gene-gene interactions involved in Fas-mediated apoptosis pathway may enhance or neutralize the chemosensitivity.

Replication and validation of genetic polymorphisms associated with survival after allogeneic blood or marrow transplant

Multiple candidate gene-association studies of non-HLA single-nucleotide polymorphisms (SNPs) and outcomes after blood or marrow transplant (BMT) have been conducted. We identified 70 publications reporting 45 SNPs in 36 genes significantly associated with disease-related mortality, progression-free survival, transplant-related mortality, and/or overall survival after BMT. Replication and validation of these SNP associations were performed using DISCOVeRY-BMT (Determining the Influence of Susceptibility COnveying Variants Related to one-Year mortality after BMT), a well-powered genome-wide association study consisting of 2 cohorts, totaling 2888 BMT recipients with acute myeloid leukemia, acute lymphoblastic leukemia, or myelodysplastic syndrome, and their HLA-matched unrelated donors, reported to the Center for International Blood and Marrow Transplant Research. Gene-based tests were used to assess the aggregate effect of SNPs on outcome. None of the previously reported significant SNPs replicated at P < .05 in DISCOVeRY-BMT. Validation analyses showed association with one previously reported donor SNP at P < .05 and survival; more associations would be anticipated by chance alone. No gene-based tests were significant at P < .05. Functional annotation with publicly available data shows these candidate SNPs most likely do not have biochemical function; only 13% of candidate SNPs correlate with gene expression or are predicted to impact transcription factor binding. Of these, half do not impact the candidate gene of interest; the other half correlate with expression of multiple genes. These findings emphasize the peril of pursing candidate approaches and the importance of adequately powered tests of unbiased genome-wide associations with BMT clinical outcomes given the ultimate goal of improving patient outcomes.

Combining therapeutic antibodies using basiliximab and etanercept for severe steroid-refractory acute graft-versus-host disease: A multi-center prospective study

Acute graft versus host disease (aGVHD) remains a major problem after allogeneic hematopoietic stem cell transplantation. Standard frontline therapy for aGVHD involves corticosteroids. However, fewer than half of patients have a lasting complete response. The long-term mortality rate of steroid-refractory aGVHD (SR-aGVHD) remains around 70%. To date, no consensus has been reached regarding the optimal salvage treatment for SR-aGVHD. We performed the first prospective, multi-center clinical trial to assess the efficacy and safety of a novel approach to treat severe (grades III-IV) SR-aGVHD with the combination of basiliximab and etanercept. Sixty-five patients with severe SR-aGVHD from six centers were included. The median number of basiliximab infusions was 4 (range 2-11) and of etanercept was 9 (range 2-12). At day 28 after starting the combination treatment, overall response (complete and partial response: CR+PR) to second-line treatment was 90.8% with 75.4% being CR. The incidences of CR per organ were 100%, 73.8%, and 79.7% for skin, liver, and gut involvement, respectively. Patients >30-y old (p = 0.043, RR = 3.169), development of grades III-IV liver aGVHD (p = 0.007, RR = 5.034) and cytomegalovirus (CMV) reactivation (p = 0.035, RR = 4.02) were independent predictors for incomplete response. Combined treatment with basiliximab and etanercept resulted in improved CR to visceral aGVHD and significantly superior 2-y overall survival (54.7% vs. 14.8%, p <0.001) compared with classical salvage treatments. Our data suggest that the combination of basiliximab and etanercept may constitute a promising new treatment option for SR-aGVHD.

The effects of genomic polymorphisms in one-carbon metabolism pathways on survival of gastric cancer patients received fluorouracil-based adjuvant therapy

5-fluorouracil (5-FU) is widely used to treat patients with gastric cancer (GC). However, the response rate is quite heterogeneous. The single nucleotide polymorphisms (SNPs) and their interactions of genes in the one-carbon metabolism (OCM) pathway, including Methylenetetrahydrofolate reductase (MTHFR), Methionine synthase reductase (MTRR), Methionine synthase (MTR), and Thymidylate synthase (TS), significantly affect 5-FU metabolism. In this study, 650 stage II-III patients were recruited from 1998 to 2006. Among them, 251 received 5-FU treatment and other 399 patients were untreated. The Cox regression analysis, log-rank tests and Kaplan-Meier plots were adopted. In the chemotherapy cohort, MTRR 66 GA + GG genotypes decreased death risk, however, the protect effect of MTRR 66 GA + GG disappeared when GC patients simultaneously had MTHFR 677TT + TC or MTR 2756GG + GA genotypes. TS 5'-UTR 2R3R + 3R3R genotypes also prolonged overall survival of patients treated with 5-FU. And this favorable prognosis obviously enhanced when GC patients simultaneously had TS 3'-UTR DD + DI and TS 5'-UTR 2R3R + 3R3R genotypes. Our findings showed that the polymorphisms of MTRR 66 A > G and TS 5'-UTR 3R > 2R may be potential prognostic factors for GC patients receiving 5-FU.

Polymorphism in one-carbon metabolism pathway affects survival of gastric cancer patients: Large and comprehensive study

Although it has been shown that polymorphisms in one-carbon metabolism (OCM) pathway are associated with gastric cancer (GC), their interactions and contributions for patients' survival are elusive. In this study, we investigated the effects of polymorphisms and their interactions on the survival of GC patients, including genes of Methylenetetrahydrofolate reductase (MTHFR 677C > T, 1298A > C), Methionine synthase reductase (MTRR 66A > G), Methionine synthase (MTR 2756A > G), and Thymidylate synthase (TS 3'-UTR ins6 > del6, 5'-UTR 2R > 3R). We recruited 919 GC patients from 1998 to 2006. The Kaplan-Meier plots, Cox regression analyses and the log-rank tests were carried out in this study. MTHFR 1298CC genotype showed protective effect (HR = 0.444, 95% CI = 0.210-0.940). MTRR 66 GA + GG genotypes decreased the risk of death (HR = 0.793, 95% CI = 0.651-0.967) in general, and in subgroups with more pronounced diffuse type, greater depth of invasion (T2/T3/T4), higher level lymph node metastasis (N1/N2/N3), advanced TNM stages (II/III level) and 5-Fu treatment. However, the improved survival disappeared when GC patients simultaneously had MTR 2756 GA + GG genotypes (HR = 1.063, 95% CI = 0.750-1.507). Although MTRR 66GA genotype was not associated with the survival of GC patients, patients with simultaneous MTRR 66GA and MTR 2756AA genotypes exhibited significant risk reduction of death (HR = 0.773, 95% CI = 0.609-0.981). MTHFR 1298 CA + CC combined with TS 5-UTR 2R3R + 3R3R genotypes (HR = 0.536, 95% CI = 0.315-0.913) also increased patient survival rates. Our results suggest that the MTRR 66A > G and MTHFR 1298A > C polymorphisms may be useful prognostic biomarkers for GC patients.

Functional polymorphisms in apoptosis pathway genes and survival in patients with gastric cancer

The FAS, FAS ligand (FASL), and CASP8 are key regulators for apoptosis and their deregulations play an important role in carcinogenesis. However, the effects of promoter polymorphisms of the FAS, and FASL, and CASP8 genes on the survival of gastric cancer are unknown. In this study, we investigated the association of four polymorphisms (FAS -1377G>A, -670A>G, FASL -844C>T, and CASP8 -652 6N ins>del) with the clinical outcome of 940 gastric cancer patients in a Chinese population. The correlation between genotype and survival outcomes was assessed by the Kaplan-Meier method, Cox proportional hazards models and the log-rank test. Our results revealed that individuals with CASP8 -652 6N ins/del+del/del genotypes had a decreased risk of death compared with those with ins/ins genotype (log-rank P=0.005; hazard ratio=0.75, 95% confidence interval=0.62-0.92). The protective effect of the del allele was further confirmed in subgroups of patients with tumor size ≤ 5 cm (0.66, 0.50-0.86) and T2 depth invasion (0.59, 0.37-0.94), but no significant association was observed in the subgroups of lymph node metastasis (0.67, 0.47-0.97), and distance metastasis (0.73, 0.60-0.90). Our findings suggest that, if validated in different independent populations, the CASP8 -652 6N ins>del polymorphism may serve as a promising genetic marker for gastric cancer prognosis.

Donor TLR9 gene tagSNPs influence susceptibility to aGVHD and CMV reactivation in the allo-HSCT setting without polymorphisms in the TLR4 and NOD2 genes

Owing to ethnicity of the population, those best confirmed polymorphisms in the TLR (toll-like receptor)4 and NOD2 genes with significantly prognostic impact on allogeneic hematopoietic SCT (allo-HSCT) seem to be more applicable to Europeans and are nonpolymorphic in the Asian population. The influence of innate immunity gene polymorphisms on the outcomes of allo-HSCT in those populations has been questioned. We evaluated the influence of 10 candidate single nucleotide polymorphisms (SNPs) in the TLR1, TLR2, TLR3, TLR8 and TLR9 genes on the outcomes of allo-HSCT in a Chinese population including 138 pairs of patients and unrelated donors and a second cohort of 102 pairs of patients and HLA-identical sibling donors. We found that two tagSNPs in the TLR9 gene in the donor side, +1174 A/G (rs352139) and +1635 C/T (rs352140), influenced the risk of acute GVHD (aGVHD) and CMV reactivation. Furthermore, the presence of the susceptible haplotype (A-C) in donor may be an informative predicator of worse OS at 5 years compared with those with the G-C and G-T haplotypes (58% vs 82.9%, P=0.024). Our data suggested an unrecognized association between donor TLR9 tagSNPs and the risk of HSCT-related complications in a population without polymorphisms in the TLR4 and NOD2 genes.

A genetic polymorphism in TOX3 is associated with survival of gastric cancer in a Chinese population

Purpose

Recently, genetic polymorphism (rs3803662C>T) in TOX3 was reported to induce the risk of breast cancer. In this study, we hypothesized that rs3803662 could influence gastric cancer survival outcomes.

Methods

With multiplex SNaPshot method, we genotyped TOX3 rs3803662 in 880 gastric patients with surgical resection. The association between genotype and survival outcomes was performed by the Kaplan-Meier method, Cox regression analysis models and the log-rank test.

Results

There was no association in the analyses of rs3803662 and survival of gastric cancer. However, the stratified analysis by histology showed that rs3803662 CT/TT genotype was associated with a significantly better survival for diffuse-type gastric cancer (log-rank p = 0.030, hazard ratio [HR]  = 0.67, 95% confidence interval [CI]  = 0.46–0.96), than the CC genotype. In addition, this favorable effect was especially obvious among gastric cancer patients with tumor size >5 cm, T3 and T4 depth of invasion, lymph node metastasis, no drinking, no distant metastasis, no chemotherapy and gastric cardia cancer.

Conclusions

TOX3 rs3803662 might play an important role in the prognostic outcome and treatment of gastric cancer, especially perhaps further help in explaining the reduced risk of death associated with diffuse-type gastric cancer.

A genetic variant in ERCC2 is associated with gastric cancer prognosis in a Chinese population

Endogenous and exogenous factors can induce DNA damage, leading to increased risk of cancer. Nucleotide excision repair (NER) is considered as the most versatile DNA repair pathway to deal with a variety of different DNA lesions. ERCC1 and ERCC2 are the two important proteins in NER pathway. In this study, we investigated the association of three functional single nucleotide polymorphisms (SNPs) (ERCC1 rs11615, ERCC2 rs13181 and ERCC2 rs1799793) with the clinical outcome of 940 gastric cancer patients in a Chinese population. Multiplex SNaPshot technology was used to genotype these three SNPs. Our results revealed that individuals with ERCC2 rs13181TG/GG genotypes had a decreased risk of death compared with those with TT genotype [log-rank P = 0.008; adjusted hazard ratio = 0.68, 95% confidence interval = 0.51-0.91] and this protective effect was more pronounced among the subgroups of patients with tumour size ≤ 5 cm (0.59, 0.39-0.89), non-cardia gastric tumour (0.69, 0.48-0.98), no lymph node metastasis (0.55, 0.32-0.96), no distant metastasis (0.70, 0.52-0.95) and chemotherapy (0.39, 0.21-0.72). We conclude that ERCC2 rs13181 polymorphism could play different roles in the overall survival of gastric cancer. Further larger studies should be conducted to validate our findings.

Genetic variations in T-cell activation and effector pathways modulate alloimmune responses after allogeneic hematopoietic stem cell transplantation in patients with hematologic malignancies

BACKGROUND

Recently, several important polymorphisms have been identified in T-cell activation and effector pathway genes and have been reported to be associated with inter-patient variability in alloimmune responses. The present study was designed to assess the impact of these genetic variations on the outcomes of allogeneic hematopoietic stem cell transplantation.

DESIGN AND METHODS

We first investigated ten single nucleotide polymorphisms in six genes, CD28, inducible co-stimulator, cytotoxic T-lymphocyte antigen 4, granzyme B, Fas and Fas ligand, in 138 pairs of patients and their unrelated donors and a second cohort of 102 pairs of patients and their HLA-identical sibling donors.

RESULTS

We observed that patients receiving stem cells from a donor with the cytotoxic T-lymphocyte antigen 4 gene CT60 variant allele (AA genotype) had a reduced incidence of grades II-IV acute graft-versus-host disease; however, they experienced early cytomegalovirus infection and relapsed more frequently, which suggested an interaction between the donor cytotoxic T-lymphocyte antigen 4 gene CT60 AA genotype and reduced T-cell alloreactivity. Furthermore, an unrelated donor with the granzyme B +55 variant genotype (AA) was an independent risk factor for development of grades II-IV acute graft-versus-host disease (P=0.024, RR=1.811). Among patients with acute myelogenous leukemia, those with the Fas -670 TT genotype were at higher risk of relapse (P=0.003, RR=3.823). The presence of these susceptible alleles in the donor and/or patient resulted in worse overall survival (54.9% versus 69.5%, P=0.029).

CONCLUSIONS

Our data suggest that genotype analysis of T-cell activation and effector pathway genes can be used for risk assessment for patients with hematologic malignancies before hematopoietic stem cell transplantation.

Clinical significance of SOD2 and GSTP1 gene polymorphisms in Chinese patients with gastric cancer

BACKGROUND

Excessive reactive oxygen species (ROS) accumulation is a common phenomenon in carcinogenesis. However, the rationale behind ROS involvement in gastric cancer is unclear. In this study, the authors investigated the clinical significance of the single nucleotide polymorphisms (SNPs) of 2 ROS metabolic process-related genes: superoxide dismutase 2 (SOD2) and glutathione S-transferase π (GSTP1).

METHODS

In total of 929 patients with gastric cancer who had definitive clinicopathologic and follow-up data were collected. SOD2 reference SNP 4880 (rs4880) and GSTP1 rs1695 genotyping were examined in DNA samples extracted from paraffin-embedded tumor tissue. Association of the 2 SNPs with each clinicopathologic feature was analyzed using the Pearson chi-square test and the independent Student t test. Gastric cancer-specific overall survival was analyzed using Kaplan-Meier curves and log-rank tests. Multivariate Cox regression analyses of these SNPs also were performed.

RESULTS

The SOD2 rs4880 CT + CC genotypes were significantly associated with a high level of lymph node metastasis (P = .023), whereas the GSTP1 rs1695 GA + GG genotypes were significantly associated with larger tumor size (>5 cm long; P = .048). Kaplan-Meier and Cox regression data indicated that the SOD2 rs4880 CT + CC genotypes alone (hazard ratio, 1.299; 95% confidence interval, 1.053-1.603; P = .015) and the GSTP1 rs1695 GA + GG combined genotypes (hazard ratio, 1.496; 95% CI, 1.078-2.074; P = .016) were independent predictors for overall survival.

CONCLUSIONS

The current data, based on a large cohort (n = 929) of Chinese patients with gastric cancer, suggested that the presence of SOD2 rs4880 and GSTP1 rs1695 genotypes may contribute to cancer progression as well as tumor aggressiveness. The components of ROS metabolism pathways may be potential therapeutic targets for this aggressive malignancy.