DNA-array of gene variants in venous leg ulcers: detection of prognostic indicators.

OBJECTIVE: Wound healing in venous leg ulcer (VLU) is a multi-step process involving complex pathways. Scanty knowledge at molecular level hinders clinical assessment and treatment. Anomalous handling of local iron overload, as well as unbalancing in matrix metalloproteinases (MMPs) and transglutaminase, has a recognized role in VLU establishment. We selected a number of single nucleotide polymorphisms (SNPs) in candidate genes (HFE, FPN1, MMP12, and FXIII) involved in VLU to identify potentially prognostic markers by means of DNA-array technology. METHODS AND RESULTS: The DNA-array-genotyping was assessed in 638 subjects for the following SNPs: HFE (C282Y, H63D), FPN1 (-8CG), MMP12 (-82AG) and FXIII (V34L). Of the subjects, 221 were affected by VLU (171 primary and 50 post-thrombosis), 112 by severe chronic venous disease (CVD) (CEAP, C3-C4), while 305 were matched healthy controls. The HFE and FXIII SNPs had been previously genotyped by conventional polymerase chain reaction (PCR)-methods on the same group of subjects (J Vasc Surg 2005;42:309; J Vasc Surg 2006;44:554; J Vasc Surg 2006;44:815). For the purpose of DNA-array, they were re-genotyped by means of array-techniques resulting in a 100% matching. Intergroup statistical comparisons were performed. In the risk computation, the FPN1 -8GG genotype had an overall CVD risk of 4.3 (95% CI, 1.6-12) and a VLU risk of 5.2 (95% CI, 1.9-15) virtually the same among primary VLU (4.98; 95% CI, 1.82-14.9). The MMP12-82AA genotype had a VLU risk of 1.96 (95% CI, 1.18-3.2) only in primary VLU (P = .01). In the genotype-ulcer size association studies, from a subgroup of 167 cases, we observed a smaller mean ulcer size in the MMP12 GG-genotype compared with the other genotypes (P = .001). Combining the present results with our previous published data on the same population, we suggest them to apply as tentative prognostic indicators in primary CVD. CONCLUSION: By analyzing simultaneously selected SNPs, it might be possible to glean precious information in predicting VLU onset or in stratifying patients according to their potential to heal. Although significant, our findings must be considered preliminary and the proposed prognostic indicators considered with caution, before ulterior more extensive studies in different populations can eventually confirm the present findings.

Methylenetetrahydrofolate reductase C677T and A1298C gene variants in adult non-Hodgkin's lymphoma patients: association with toxicity and survival.

BACKGROUND AND OBJECTIVES: Common methylenetetrahydrofolate reductase gene variants (MTHFR C677T and A1298C) have been described to have opposite effects on cancer patients. They may reduce cancer susceptibility and increase drug-related toxicity when folate antagonists (e.g. methotrexate) are utilized. We analyzed 110 patients with high-grade non-Hodgkin's lymphoma (NHL), 68 of whom were eligible for a chemotherapy combination containing methotrexate (MACOP-B) and 42 for chemotherapy without methotrexate (CHOP). DESIGN AND METHODS: Patients were genotyped by polymerase chain reaction and stratified by MTHFR variants. These data were related to the toxicity (WHO grade GO-4) that the patients suffered and their survival. Overall 64 cases (58.2%) developed some form of toxicity and 23 (20.9%) had grade 3/4 toxicity. RESULTS: When considering toxicity of any grade (grade 1-4), the 677TT genotype was significantly over-represented among cases with mucositis (OR=4.85; 95% CI, 1.47-15.97; p=0.009) and those with hepatic toxicity (OR=3.43; 95% CI, 0.99-11.86; p=0.052). Sub-analyses in the group treated with MACOP-B showed a slight increase in the risk of developing mucositis (OR=5.22; 95% CI, 1.20-27.27; p=0.03), and a strong increase in the risk of hepatic toxicity (OR=7.08; 95% CI, 1.38-36.2; p=0.019) and thrombocytopenia (OR=7.69, 95% CI 1.0-58.94; p=0.05). Interestingly, compared to the risk of developing toxicity of any grade, the risk of developing severe (grade 3/4) mucositis was almost doubled in the whole group of cases with 677TT (OR=8.13; 95% CI 1.61-41.04; p=0.011) and dramatically increased in the MACOP-B-treated cases with this gene variant (OR=24.6; 95% CI 2.49-87.41; p=0.001). There were significant results for 1298CC cases exclusively for mucositis (any grade, OR=5.33; 95% CI, 1.25-22.70; p=0.023 and OR=9.15; 95% CI, 1.14-73.41; p=0.037; for the whole group and the MACOP-B-treated group, respectively). Similarly, the risk of 1298CC patients developing severe mucositis increased (OR=9.24; 95% CI, 1.47-58.0; p=0.017 and OR=11.53; 0.93-143.18; p=0.057; in the whole group and in the MACOP-B-treated group, respectively). Event-free survival analysis revealed a lower probability of event-free survival at 5 years for 677T-carriers (log-ranks, p=0.05 and p=0.07 in the whole group and in the MACOP-B-treated group, respectively). More significant results were obtained when 1298CC cases were excluded from the reference group (log-ranks, p=0.03 and p=0.04, respectively). No significant associations were found in the CHOP-treated group. INTERPRETATION AND CONCLUSIONS: Our data suggest that MTHFR gene variants play a critical role in NHL outcome, possibly by interfering with the action of methotrexate with significant effects on toxicity and survival. Genotyping of folate pathway gene variants might be useful to enable reduction of chemotherapy toxicity and/or to improve survival by indicating when dose adjustments or alternative treatments are necessary.

Common gene polymorphisms in the metabolic folate and methylation pathway and the risk of acute lymphoblastic leukemia and non-Hodgkin's lymphoma in adults.

Folate and methionine metabolism is involved in DNA synthesis and methylation processes. Polymorphisms in the genes of folate metabolism enzymes have been associated with some forms of cancer. In a case-control study, we evaluated whether four common polymorphisms in methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MS A2756G), and methionine synthase reductase (MTRR A66G) genes may have a role in altering susceptibility to adult acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). We analyzed DNA of 120 adult ALL, 200 NHL, and 257 healthy control subjects. Individual carrying the MTHFR 677TT genotype showed a 3.6-fold decreased ALL risk [odds ratio (OR) 0.28, 95% confidence interval (95% CI) 0.12-0.72] than wild-types. Similarly, MS 2756GG individuals showed a 5.0-fold decreased ALL risk (OR 0.20, 95% CI 0.02-1.45) than wild-types. In combined results, subjects with the MTHFR 677CT/TT and MS 2756AG/GG genotypes revealed a 3.6-fold ALL risk reduction (OR 0.28, 95% CI 0.14-0.58) and those with the MTHFR 677TT and MTRR 66AG genotypes revealed a 4.2-fold ALL risk reduction (OR 0.24, 95% CI 0.06-0.81). Finally, those with the MS 2756AG/GG and MTRR 66AG/GG genotypes revealed a 2.2-fold ALL risk reduction (OR 0.45, 95% CI 0.10-0.85). Single analysis for NHL did not show any significant difference for all the polymorphisms investigated, but in the low-grade NHL subgroup, we found a 2.0-fold risk reduction for the MTRR 66GG homozygous genotype (OR 0.50, 95% CI 0.25-0.99), which was higher (OR 0.37, 95% CI 0.14-0.85) when analyzed in combination with MS 2756AA genotype. These data are in accordance with the hypothesis that polymorphisms in the genes for folate and methionine metabolism might play a greater role in the occurrence of ALL than NHL by influencing DNA synthesis and/or DNA methylation.

Factor XIIIA-V34L and factor XIIIB-H95R gene variants: effects on survival in myocardial infarction patients.

It has been demonstrated recently that coagulation factor XIII (FXIII) plays an extraordinary role in myocardial healing after infarction, improving survival in a mouse model. Common FXIII gene variants (i.e. FXIIIA-V34L and FXIIIB-H95R) significantly influence the molecular activity. To evaluate whether there is a relationship between the two FXIII gene variants and survival in patients after myocardial infarction (MI), V34L and H95R were PCR-genotyped in a cohort of 560 MI cases and follow-up was monitored. Cases with ST-segment elevation MI (STEMI) were 416 (74.3%) and 374 of these were treated with primary percutaneous coronary intervention (PCI) (89.9%). The remaining 144 patients showed non-ST-segment elevation MI (NSTEMI) at enrollment. The combined endpoint was the occurrence of death, re-infarction, and heart failure. Kaplan-Meier analysis at one year yielded an overall rate for adverse events of 24.5% with a lower incidence in the L34-carriers (28.8% vs 17.1%; log-rank, P = 0.00025), similar to that of the 416 STEMI (23.8%) being (28.0% and 16.9%; VV34- and L34-carriers respectively; log-rank, P = 0.001). Primary PCI-group had a slight lower incidence (22.9%) of adverse events (26.8% and 17.1%; VV34- and L34-carriers respectively; log-rank, P = 0.009). During hospitalization, 506 patients received PCI (374 primary PCI and 132 elective PCI). Significance was conserved also in the overall PCI-group (28.6% and 17.8%; VV34- and L34-carriers respectively; log-rank, P = 0.001). Similar findings were observed at 30 days follow-up. Cases carrying both FXIII variants had improved survival rate (log-rank, P = 0.019). On the other hand, minor bleeding complications were found increased in L34-carriers (P = 0.0001) whereas major bleeding complications were not. Finally, more direct evidence on the role of FXIII molecule on survival might come from the fact that despite significant FXIII antigen reductions observed in cases after MI, regardless the FXIII genotype considered, L34-carriers kept almost normal FXIII activity (VV34- vs L34-carriers; P < 0.001). We conclude that FXIII L34-allele improves survival after MI in all the groups analyzed, possibly through its higher activity associated with assumable positive effects on myocardial healing and recovered functions. Genetically determined higher FXIII activity might influence post-MI outcome. This paves the way for using FXIII molecules to improve myocardial healing, recovery of functions, and survival after infarction.

Prognostic role of factor XIII gene variants in nonhealing venous leg ulcers.

OBJECTIVE: Many factors impair healing of chronic venous ulcer (CVU), and many theories have been proposed to explain their pathogenesis. Coagulation factor XIII (FXIII) influences tissue regeneration and angiogenesis with effects on wound healing. Because FXIII properties depend upon its genetic variants, we investigated whether intragene polymorphisms may have modulating effects on the CVU area. METHODS: The study included 121 patients with nonhealing CVUs (CEAP clinical class C6) that included 67% with primary chronic venous disease (CVD), 26% with post-thrombotic ulcers, and 7% with mixed ulcer origin. Polymerase chain reaction was used to genotype them for Val34Leu, Pro564Leu, and Tyr204Phe variants in the FXIII-A subunit gene and for His95Arg variant in the FXIII-B subunit gene. The same variants were analyzed in 102 controls, healthy subjects who were case-matched by age and gender. RESULTS: Genotype distribution for all polymorphisms investigated was not significantly different between cases and controls. Conversely, our CVU cases had a mean ulcer area inversely related with the presence of both Leu34 and Leu564 alleles (ValVal, 12.3 +/- 22.4 cm2 vs LeuLeu, 3.9 +/- 2.6 cm2, P = .002; ProPro, 10.2 +/- 21.2 cm2 vs LeuLeu, 2.9 +/- 1.4 cm2, P = .002). In combined analysis, those cases who were wild-type for both variants (ValVal34/ProPro564) had a further increase in mean ulcer size compared with cases carrying both variants (Leu34/Leu564) (13.3 +/- 27.1 cm2 vs 5.2 +/- 5.6 cm2; P = .034). CONCLUSIONS: No correlation exists between FXIII genotypes and the prevalence of chronic venous ulcers, thus demonstrating that FXIII polymorphisms have no role in ulcer development. In contrast, FXIII-gene variants, in particular the non-wild-type alleles Leu34 and Leu564, were associated with a smaller venous ulcer surface and might have favorable effects on reparative processes.

Influence of gene polymorphisms in ulcer healing process after superficial venous surgery.

OBJECTIVE: Role of superficial venous surgery in reducing the time it takes for ulcers to heal is still controversial, although all studies confirm a significant reduction in ulcer recurrences. Recently, the HFE-C282Y and FXIII-V34L gene variants demonstrated a role in the risk of venous ulceration in primary chronic venous disorder (CVD) and in modulating lesion size in chronic venous ulcer (CVU), respectively. This study was conducted to investigate the role of HFE-C282Y and FXIII (V34L and P564L) gene variants in ulcer healing time after superficial venous surgery, by assessing the outcome of a cohort of homogeneous CVU patients. METHODS: The study selected 91 patients affected by primary CVU (CEAP C6, Ep, Asp, Pr), with the exclusion of any other comorbidity factor involved in delayed healing process, who underwent surgery. We assessed the ulcer area and the healing time. Patients were genotyped by polymerase chain reaction for FXIII (V34L and P564L) and for HFE-C282Y substitutions. RESULTS: Globally, CVU cases had a postoperative mean healing time of 8.5 +/- 5.7 weeks. For the subset of cases above and below the median value (M = 8.0 weeks), FXIII-V34L genotype distribution significantly differed (P < .0001). In addition, Kaplan-Meier analysis yielded specific healing time profiles for the different FXIII-V34L classes of genotype (P = .00001), with an increased risk of delayed healing for the FXIII-VV genotype (hazard ratio, 4.14; 95% confidence interval, 2.1 to 8.2; P = .00005). Although FXIII-P54L genotype distributions did not differ, homozygous 564LL cases (P = .005) and double carriers for both FXIII variants (P < .0001), had a significantly reduced healing time vs wild types. No differences in healing time were observed between carriers and noncarriers of the HFE-C282Y variant, whereas when these cases were stratified by FXIII-V34L genotypes, the L34 carriers had a significantly shorter healing time, irrespective of the HFE genotype. CONCLUSION: The FXIII-34L variant was significantly associated with shorter healing time after superficial venous surgery, suggesting a role in the healing and tissue regeneration phases. Conversely, HFE-C282Y, despite its role in ulcer establishment, did not affect the postoperative healing time. In perspective, the identification of patients with a poor prognosis may give clinicians the opportunity to modify management and to target tailored therapies in the view of a new and alternative concept of treatment based on pharmacogenomics.

Hemochromatosis C282Y gene mutation increases the risk of venous leg ulceration.

OBJECTIVE: Chronic venous disease (CVD) is the most common vascular disorder, progressing in approximately 10% of cases toward chronic venous leg ulceration, whereas the hemochromatosis gene (HFE) C282Y mutation is the most common recognized genetic defect in iron metabolism. Because CVD leads to local iron overload in the affected legs, we investigated whether two common HFE mutations could increase the risk of chronic venous leg ulceration. METHODS: This was a case-control study at the Vascular Diseases Center, University of Ferrara, Italy. From a cohort of 980 consecutive patients affected by severe CVD (CEAP clinical classes C4 to C6) we selected 238 cases with the exclusion of any other comorbidity factor potentially involved in wound etiology (group A). They were subdivided into group B, including 137 patients with ulcer (classes C5 and C6: 98 primary and 39 postthrombotic cases), and group C, including 101 cases with no skin lesions (class C4). They were completely matched for sex, age, and geographic origin with 280 healthy controls (group D). A total of 518 subjects were polymerase chain reaction genotyped for HFE mutations (C282Y and H63D). We assessed the risk of ulceration by comparing the prevalence of ulcer in homogenous cases with and without the HFE variants. Other main outcome measures were the sensitivity, specificity, and predictive values of the genetic test in CVD cases. RESULTS: C282Y mutation significantly increases the risk of ulcer in primary CVD by almost seven times (odds ratio, 6.69; 95% confidence interval, 1.45-30.8; P = .01). Application of the HFE test in primary CVD demonstrated increased specificity and positive predictive values (98% and 86%, respectively), with negligible sensitivity and negative predictive values. CONCLUSIONS: The overlap of primary CVD and the C282Y mutation consistently increases the risk of developing venous leg ulceration. These data, which have been confirmed in other clinical settings, suggest new strategies for preventing and treating primary CVD. CLINICAL RELEVANCE: The number of patients affected by primary CVD is so great that the vast majority of ulcers are also related to this common problem. On the other hand, there is not a reliable way for identifying in advance, from the broad base of primary CVD patients (20-40% of the general population), the high risk minority (10% of primary CVD cases) who will develop a venous ulcer. In such cases, a simple C282Y blood genetic test demonstrated an elevated specificity in predicting ulcer development (98%, CI 95%, 92.8-99.7). The genetic test could be applied starting from the C2 class, varicose veins, the most common situation observed in clinical practice. In perspective, the presence of the C282Y mutation would strengthen the indications and priorities for surgical correction of superficial venous insufficiency.

Factor XIII V34L polymorphism modulates the risk of chronic venous leg ulcer progression and extension.

Low Factor XIII (FXIII) activity has been reported in the blood of patients with chronic venous leg ulcer (CVU). In vivo studies have described increased wound healing in CVU patients treated with FXIII concentrate, and in vitro studies have shown increased regenerative capacity in FXIII-treated fibroblasts. In addition, a common G-to-T polymorphism in the FXIIIA-subunit gene (V34L) significantly increases the activity and modifies the cross-linking properties of the FXIII molecule and this variant has been investigated as a protective factor against thrombosis, a recognized risk factor for CVU establishment. Therefore, the role of FXIII levels, FXIII V34L, FVR506Q, and FIIG20210A, common gene polymorphisms in the pathogenesis of CVU was investigated. Ninety-one patients with CVU and 195 healthy controls (91 of them sex- and age-matched) were PCR-genotyped for the FXIIIV34L, FVR506Q, and FIIG20210A substitutions and FXIIIA-subunit levels were determined by immuno-electrophoresis. The extent of the venous ulcer surface in patients was measured by computer software. The allele frequency and the genotype distribution of the FXIII polymorphism did not show significant differences between the whole group of cases and controls as well as prothrombin variants did. On the contrary, the FVR506Q variant (FV Leiden) allele was more frequent in patients, yielding a significant OR value of 5.93 (95 percent CI, 1.83-19.17; p= 0.003). Considering only CVU cases secondary to a post-thrombotic syndrome (n= 24), FV Leiden yielded a greater OR value of 16.08 (95 percent CI, 4.33-59.6; p < 0.0001). When the CVU cases were stratified by the three possible FXIII genotypes, a significant trend toward a lower mean value of the ulcerated area was clearly evident as the number of the polymorphic alleles (L34) increased in the genotype of patients (VV = 11.9 cm(2,)+/- 23.6; VL = 6.1 cm(2,)+/- 6.9; LL = 4.1 cm(2,)+/- 2.8; p= 0.01). On the other hand, FXIIIA antigen levels were similar between CVU cases and matched controls, but 11 percent of cases had FXIII deficiency (FXIIIA