Pharmacogenomics of Methotrexate Pathway in Rheumatoid Arthritis Patients: Approach toward Personalized Medicine

Background: Methotrexate (MTX) is one of the most common medications used for rheumatoid arthritis (RA) treatment. Single-nucleotide polymorphisms (SNPs) could potentially predict variability in therapeutic outcomes. Aim: This study aims to assess the impact of SNPs in genes encoding for the MTX pathway for predicting clinical and therapeutic responses to MTX in a cohort of Egyptian patients with RA. Subjects and Methods: Data from 107 Egyptian RA patients (aged 44.4 ± 11.4 years) treated with MTX monotherapy, for a duration of 3.7 ± 3.3 years, were collected. Genotypes of 10 SNPs from four different genes were analyzed using the allelic discrimination PCR technique. Results: The ATIC rs3821353 G/T (p = 0.034) and the C/T and C/C of SLC19A1 rs7279445 (p = 0.0018) were associated with a non-response to MTX, while DHFR rs10072026 C/T and C/C were associated with a good response (p < 0.001). Carriers of the ATIC rs382135 3 G (p = 0.001) and ATIC rs4673990 G (p < 0.001) alleles were more likely to develop RA, while the SLC19A1 rs11702425 T (p < 0.001) and GGH rs12681874 T (p = 0.003) allele carriers were more likely to be protected against RA. Carriers of the ATIC rs4673990 A/G genotype (p < 0.001) were at risk of developing RA, while carriers of the following genotypes were mostly protected against RA: ATIC rs3821353 T/T (p < 0.001), ATIC rs3821353 G/G (p = 0.004), SLC19A1 rs11702425 T/T (p = 0.001), SLC19A1 rs11702425 C/T (p = 0.003), GGH rs12681874 C/T (p = 0.004) and GGH rs12681874 T/T (0.002). Conclusion: The genotyping of genes involved in the MTX pathway may be helpful to predict which RA patients will/will not benefit from MTX, and thus, may help to apply a personalized medicine approach in RA.

Homocysteine, insulin-like growth factor one and oestrogen levels in patients with erectile dysfunction-associated chronic hepatitis C virus infection

We assessed the change of homocysteine (Hcy), insulin-like growth factor one (IGF-Ι) and oestrogen (E2) levels in patients with erectile dysfunction (ED) associated with chronic hepatitis C virus (HCV) infection. Eighty-five male patients with chronic HCV and/or ED were enrolled in this study. Seventy-five men were assigned to three equal groups (n = 25/each); Group A: patients who had chronic HCV and ED. Group B: patients who had chronic HCV and had no ED complaint. Group C: patients who had ED with no chronic HCV. In addition to 10 control patients with no ED or chronic HCV (Group D). All patients were subjected to: detailed medical and sexual history, complete physical examination, laboratory assessment including measurement of serum Hcy, IGF-1 and E2. The means of international index of erectile function scores were 8 and 16 in groups A and C respectively. There were significant differences in Hcy, IGF-I and E2 among study groups (p < 0.05 for each). There were significant differences in Hcy between patients with Child B and Child C. A strong association between severity of ED and chronic HCV was demonstrated. There was statistically significant increase of Hcy and E2 levels and reduction in IGF-I level in patients with ED associated with chronic HCV infection.

Impact of hepatitis C virus infection on neutrophil oxidative burst function in hemodialysis patients

Polymorphonuclear leukocyte (PMN) functions have been studied extensively in hemodialysis (HD) patients; however, results are contradictory and the mechanisms that modulate phagocytosis and oxidative burst are not completely understood. Hepatitis C virus (HCV) is a frequent complication of HD that may be associated with disturbed PMN function; however, the impact of HCV infection on neutrophil oxidative burst function in HD patients is unknown. We investigated Neutrophil oxidative burst function in 24 HD patients (15 HCV-positive and, 9 HCV-negative patients) before and after dialysis. HCV-RNA was detected by RT-nested PCR while, quantitative measurement of oxidative burst function was assessed by flowcytometry. Neutrophil Oxidised burst function was significantly diminished in HD patients as comapred to controls (P = 0.001, oxidised PMN (%); P = 0.02 mean flueresnce intensity, MFI), and in pre-dialysis as compared to post-dialysis samples (oxidised PMNs (%): 60.5 +/- 3.2 vs. 72.1 +/- 3.9, P = 0.02); (MFI: 352 +/- 42 vs. 500 +/- 50, P = 0.03). Alteration in Neutrophil oxidative burst function in the pre-dialysis samples was significant in HCV-positive patients as compared to HCV-negative patients (oxidized PMNs (%): 50 +/- 2.9 vs. 63 +/- 5.1, P = 0.02); (MFI: 291 +/- 31 vs. 438 +/- 64, P = 0.006). Marked reduction in E. coli induced burst in pre-dialysis samples compared to post-dialysis was found in HCV-positive when compared to HCV-negative patients (oxidized PMNs (%): 50 +/- 2.9 vs. 74.8 +/- 4.7, P = 0.001), (MFI: 291 +/- 31 vs. 493 +/- 63, P = 0.002). In conclusion, a possible role of concomitant HCV infection in alteration of Neutrophil oxidative burst function is highly suggested.

Age Related Testosterone Depletion in Patients With Erectile Dysfunction

PURPOSE

We assessed the pattern of age related testosterone depletion in patients with erectile dysfunction.

MATERIALS AND METHODS

A total of 305 patients with erectile dysfunction who had a normal testosterone level at baseline visit and who completed the study were candidates for analysis. Erectile function was assessed using the International Index of Erectile Function. Patients underwent routine laboratory investigations plus total testosterone and prolactin assessment at the baseline visit and on a yearly basis for 4 years.

RESULTS

The mean age +/- SD was significantly higher in 210 patients with decreased testosterone (55.3 +/- 7.3 years) than in 95 patients with steady testosterone (remaining within the normal range) (50.8 +/- 10.2 years). There was a significant decrease in yearly mean testosterone level throughout the study in all the age groups (determined by decades) older than 30 years. Of the study population 68.9% had decreases in testosterone levels throughout the 4 years of visits. Hypogonadism (testosterone lower than normal range) developed in 7.6% of the study population. There was a significant decrease in mean testosterone at any visit in comparison to previous visits. There were significant associations between decreased levels of testosterone and increased severity of erectile dysfunction at baseline visit, longer duration and poor metabolic control of diabetes, ischemic heart disease, hyperprolactinemia and low desire.

CONCLUSIONS

This study clearly demonstrated a decrease in testosterone level throughout the 4-year followup in patients with erectile dysfunction. Patients with decreasing testosterone were older than patients with a steady testosterone level.

Pattern of endocrinal changes in patients with sexual dysfunction

INTRODUCTION

Many patients with endocrinal changes (endocrinopathy) have some degrees of sexual dysfunction that necessitate assessment and treatment.

AIM

To assess the prevalence, and identify the pattern, of endocrinopathy in patients with sexual dysfunction in our community.

METHODS

A total of 1,248 male patients with sexual dysfunction were enrolled in this study. Patients were screened for erectile dysfunction (ED) and sexual desire by the erectile function and the sexual desire domains of the International Index of Erectile Function (IEEF). Patients underwent routine laboratory investigations as well as total testosterone and prolactin assessment. All patients were referred to an endocrinologist for clinical and biochemical assessment of their endocrine function. The evaluation consisted of comprehensive history taking, physical examination, and, as needed, laboratory investigations.

RESULTS

Mean ages+/-SD were 51.9+/-12.2 and 52.3+/-11.7 years for patients with and without endocrinopathy, respectively. Of the study population, 23.8% had endocrinopathy. The most frequent endocrinal changes were low testosterone level (15%), hyperprolactinemia (13.7%), and hypothyroidism (3.1%). There were significant associations between endocrinopathy and obesity, smoking, low desire, and premature ejaculation (P<0.05 for each). Also, significant associations were found between low desire and low testosterone level, hyperprolactinemia, and hypothyroidism (P<0.05 for each). Hyperprolactinemia was significantly associated with premature ejaculation (P<0.05) but not with low testosterone level (P>0.05). There was no significant association between endocrinopathy and age, cigarette smoking (number and duration), and ED (duration, severity, type of onset, and progression) (P>0.05 for each).

CONCLUSION

Endocrinopathy is not a rare condition among ambulatory patients with sexual dysfunction. This study provides a quantitative estimate of endocrinopathy in ambulatory patients with sexual dysfunction.

Prostatic Specific Antigen in Patients with Hypogonadism: Effect of Testosterone Replacement

INTRODUCTION

The effect of parenteral testosterone replacement therapy on prostatic specific antigen (PSA) level or the development or growth of prostate cancer is unclear.

AIM

To assess the effect of testosterone replacement on PSA level in patients with hypogonadism associated with erectile dysfunction (ED).

METHODS

A total of 187 male patients above the age of 45 with hypogonadism associated with ED were enrolled in this study. Patients were screened for ED by the erectile function domain of the International Index of Erectile Function (IIEF). Patients underwent routine laboratory investigations, plus total testosterone, and PSA assessment. Replacement treatment with parenteral testosterone every 2-4 weeks for 1 year was instituted. Total testosterone and PSA serum levels were assessed every 3 months during the treatment course.

RESULTS

Mean age +/- SD was 62.8 +/- 11.4. Of the patients 87.7% were sexually active. Of the patients 10.2% had mild, 40.6% had moderate and 49.2% had severe ED. Of the study population, 62.5% had ED complaints for less than 5 years and 84.5% had gradual onset of their complaint. The majority of the patients (91.4%) had either progressive or stationary course while the minority reported regressive course and improvement of the condition. There was a significant increase of the post-treatment testosterone level in comparison to pretreatment level (P < 0.05). No significant increase in the post-treatment PSA level in comparison to pretreatment (P > 0.05). No significant difference between pre- and post-treatment categories of PSA level (normal, borderline, high) in relation to the severity of ED (P > 0.05). There was no significant association between PSA level and the duration of testosterone replacement therapy in the study population (P > 0.05).

CONCLUSION

The current study demonstrated that the level of PSA was not significantly changed after 1 year of testosterone replacement therapy in patients with hypogonadism associated with ED.

Soluble ICAM-1 in patients with chronic hepatitis C infection: a prognostic marker of disease activity

Soluble intercellular adhesion molecule-I (sICAM-1) is an important early marker of response to inflammatory mediators and immune activation released from a variety of cells including hepatocytes. At present, the most reliable determination of severity and prognosis in chronic viral hepatitis is the histological staging of the disease which is an invasive procedure and is often not well accepted by patients. The search for alternative non-invasive methods is mandatory especially in follow ups after initial assessment by biopsy. Serum sICAM-1 level was measured in 19 patients with chronic HCV, 19 patients with non-B, non-C chronic liver diseases (NBNC-CLD) and in 19 healthy control subjects using ELISA. Serum sICAM-1 levels were significantly higher in patients with chronic HCV and in NBNC-CLD patients compared to normal subjects (mean +/- SD, [1003 +/- 453 vs. 232 +/- 177, p<0.001], and [881 +/- 328 vs. 232 +/- 177, p<0.001]), respectively. Furthermore, serum levels of sICAM-1 were significantly higher in HCV-RNA positive patients than in HCV-RNA negative patients (p<0.001). Positive correlations were detected between serum levels of sICAM-1 and serum alanine aminotranseferase (ALT) (p<0.001), aspartate aminotranseferase (AST) (p<0.001), prothrompin time (p<0.001), and alkaline phosphatase (p<0.001), while, a negative correlation with albumin was found (p<0.001). Also, there was a significant correlation between clinical, ultrasonic findings and the level of sICAM-1 in chronic HCV patients as regards hepatomegaly, splenomegaly and normal liver echogenecity. High knodell score was significantly associated with high sICAM-1 level (p<0.001) in both patient groups. while no association between sICAM-1 and fibrosis was found. In conclusion, the measurement of sICAM-1 serum levels in chronic hepatitis C and NBNC-CLD patients is a useful non-invasive marker for monitoring liver disease activity that could replace follow up liver biopsies that are mostly not welcomed by the patients.

Evolution of viral quasispecies in interferon-treated patients with chronic hepatitis C virus infection

BACKGROUND/AIMS

To evaluate whether interferon treatment failure/relapse is related to changes in hepatitis C virus quasispecies complexity (number of variants) or diversity (genetic relatedness of variants).

METHODS

We analyzed hypervariable region heterogeneity in hepatitis C virus-infected patients by heteroduplex mobility assay and by phylogenetic analysis of sequenced clones. Sera from 11 patients were tested. Response was defined biochemically and virologically. Patients were treated with 3 or 6 MIU interferon for 6 months and followed up for 6 months. Four patients were non-responders, four were transient responders and three untreated patients served as controls. Three time points were studied for the non-responders (pre-interferon, end of interferon, end of 6 months of follow-up), two for the transient responders (pre-interferon and post follow-up) and two for the controls (1 year apart). A total of 260 clones were examined by heteroduplex mobility assay and 144 clones were sequenced.

RESULTS

A linear correlation between heteroduplex mobility and nucleotide substitutions was observed, validating this method for assessment of quasispecies diversity. Although complexity at each time point was similar in all groups, diversity increased significantly with interferon treatment. The percentage of new variants in follow up was significantly higher in non-responders than in controls. These new variants exhibited a greater change in heteroduplex mobility, a higher percentage of changes in amino acids in non-responders compared to controls and were found to cluster separately from pretreatment variants when analyzed phylogenetically. These changes were less marked in transient responders.

CONCLUSIONS

These mutations may allow hepatitis C virus to escape antiviral effects of interferon therapy.

GB virus C (GBV-C/HGV) and E2 antibodies in children preliver and postliver transplant

The association of GB virus type C (GBV-C) virus and clinical disease is uncertain. The role of GBV-C and (Envelope) E2 antibody in children with liver transplants has not been determined. This study's aim is to examine the prevalence of GBV-C in children with liver transplants, to assess the relationship of GBV-C to posttransplant hepatitis, and to determine the role of E2 antibodies. Sera from 34 children, preliver and postliver transplant, between 1989-1996 were tested for GBV-C (Ribonucleic acid) RNA by the automated Abbott LCx PCR assay. Anti-E2 antibodies were detected by an Abbott immunoassay. Recent posttransplant liver biopsies were examined for hepatitis. The results of the study determined that pretransplant, four children (12%) were GBV-C RNA positive. Posttransplant, 14 (42%) children were GBV-C RNA positive. The GBV-C RNA positive conversion rate was 33% (CI 17.2-55.7%). Patients received blood products from a mean of 68 +/- 34 donors, which correlated with GBV-C acquisition. There was no difference in the incidence (32%versus 36%; p = 0.726) or severity (grade 2.00 versus 0.68; p = 0.126) of posttransplant hepatitis in the liver biopsies of GBV-C RNA negative and/or positive children, respectively. Pretransplant, nine of 32 children were anti-E2 positive. Posttransplant, eight of 32 children were anti-E2 positive, including five children who were anti-E2 positive pretransplant. Of nine children who were anti-E2 positive and GBV-C RNA negative pretransplant, three became GBV-C RNA positive posttransplant. The results of this study conclude that the prevalence of GBV-C infection in children postliver transplantation is high and that blood product transfusions correlate with GBV-C acquisition. Also, no correlation was found between GBV-C RNA and the incidence or severity of posttransplant hepatitis. Finally, E2 antibody presence before transplantation failed to provide complete protection from GBV-C acquisition.

Liver transplantation as a model to study hepatitis C virus infection

Hepatitis C virus-associated end-stage liver disease is a leading diagnosis in patients undergoing liver transplantation, accounting for approx 25% of patients transplanted at major medical centers in the United States, and for 5-15% of those transplanted worldwide (1). Although HCV infection in the early posttransplantation period usually results in indolent disease, the full clinical consequences may not be seen for five or more years after transplantation, when progressive liver failure and even hepatocellular carcinoma can develop. Orthotopic liver transplantation (OLT) provides a unique opportunity to study HCV infection for the following reasons: 1. The exact timing of infection is known (shortly after liver transplantation). 2. Possible source(s) of infection can be identified (pretransplantation infection and/or infection from the organ donor or from blood products transfused in the perioperative period). 3. Serial serum samples are often available, since these patients are typically followed in a single center. 4. Multiple liver biopsies are typically performed, which facilitates study of the histological evolution of HCV-associated liver disease.

Antienvelope antibodies are protective against GBV-C reinfection: evidence from the liver transplant model

An assay for the detection of antibody against the second envelope (E2) protein of GB virus type C (GBV-C) has been developed. Early reports suggested that this antibody was a marker of viral clearance, yet it is unknown whether anti-E2 is protective against further GBV-C infection. The primary aims were to determine (1) if posttransplantation immunosuppression alters the prevalence of anti-E2; and (2) if anti-E2 positivity pretransplantation protects against acquisition of GBV-C infection posttransplantation. Fifty-four recipients who underwent orthotopic liver transplantation for end-stage liver disease of nonviral etiologies were tested for GBV-C RNA using a PCR-based assay and anti-E2 antibodies by an enzyme-linked immunoassay. Anti-E2 was present in 35% and in 46% of patients pre- and posttransplantation, respectively. Anti-E2 positivity pretransplantation was strongly associated with anti-E2 positivity after transplantation (P < 0.001); 83% of patients with anti-E2 prior to transplantation remained anti-E2-positive after transplantation. A negative association between presence of GBV-C viremia and presence of anti-E2 was found in all patients tested either prior to or following transplantation (P=0.03). Acquisition of GBV-C infection was significantly lower in patients who were anti-E2-positive prior to transplantation (2/13) compared to those who were anti-E2-negative (12/26) (P=0.05). It is concluded that immunosuppression does not reduce the prevalence of anti-E2 after transplantation in those who are seroreactive prior to transplantation. Anti-E2 appears to be a neutralizing antibody whose presence at the time of liver transplantation protects against acquisition of GBV-C infection in the peritransplantation period.

Quantitation of hepatitis G and C viruses in the liver: evidence that hepatitis G virus is not hepatotropic

Hepatitis G virus (HGV) is prevalent in patients with chronic liver disease and has been previously detected in liver specimens. However, it is unknown whether the virus is replicating in the liver or is simply a contaminant from serum. We sought to determine whether HGV was hepatotropic and to determine whether coinfection with HGV and hepatitis C virus (HCV) influenced the level of either virus. Virus was quantitated using branched DNA (bDNA) assay for both HGV and HCV in the liver explants and pretransplant serum samples from 30 transplant recipients: Group I, HGV/HCV coinfection (n = 10); group II, HCV infection alone, (n = 8); group III, HGV alone (n = 12). In patients with coinfection HCV (RNA) titers in liver were consistently higher than those for HGV RNA (median 1.13 x 10(8) and 360,000 Eq/g respectively, P < .01). The ratio of liver/serum viral RNA was significantly higher for HCV than for HGV (median 129 and 0.3 respectively, P < .01). Levels of HCV RNA were similar in patients with HCV infection alone versus those with HGV/HCV coinfection (median; liver = 1.15 x 10(7) vs. 1.13 x 10(8) Eq/g, serum = 500,000 vs. 200,000 Eq/mL) and levels of HGV RNA in liver and serum were similar in patients with HGV infection alone compared to those with HGV/HCV coinfection (median; liver = 1.2 x 10(6) vs. 4.0 x 10(5) Eq/g, serum = 4.5 x 106 vs. 2.6 x 10(6) Eq/mL). Levels of either virus appeared unaffected by the presence of an additional virus. The high ratio of HCV RNA levels in liver compared to serum is consistent with its known hepatotropism, but this pattern was not observed for HGV. The median liver/serum ratio of HGV RNA was less than unity, a finding consistent with serum contamination of liver tissue. Thus we conclude that the liver is not the main site of HGV replication.

An animal model of Peyronie's-like condition associated with an increase of transforming growth factor beta mRNA and protein expression

PURPOSE

Transforming growth factor beta (TGF-beta) is involved in numerous vital processes including tissue fibrosis. Our objective was to study the role of TGF-beta in the induction of a Peyronie's-like condition and to produce an animal model for the further study of Peyronie's disease.

MATERIALS AND METHODS

Twenty-four adult male Sprague-Dawley rats were divided into two groups. Different concentrations of cytomodulin, a synthetic heptopeptide with TGF-beta-like activity, were injected into the tunica of each rat from the first group (n = 18). Rats in the second group (n = 6) received saline injections as a control. The tunical tissues were taken after 3 days, 2 weeks, and 6 weeks and were examined using Hart and Trichrome stains. In the same tissue samples, TGF-beta mRNA and protein expression were studied.

RESULTS

Histological alterations were observed in 15 out of 18 cytomodulin-injected rats, especially in tissue examined after 6 weeks. The most prominent changes were chronic cellular infiltration, focal and diffuse elastosis, thickening, disorganization and clumping of the collagen bundles. Results from immunoblot revealed remarkable TGF-beta1 protein expression in all the cytomodulin-injected rats only after 2 and 6 weeks. No remarkable TGF-beta2 or TGF-beta3 protein expression was observed. TGF-beta1 mRNA expression in the cytomodulin-injected rats was noticed in rats injected with higher concentrations after 3 days, while it was expressed in all rats after 2 weeks. There was no expression in the control group after either 3 days or 2 weeks.

CONCLUSIONS

Cytomodulin can induce Peyronie's-like condition in the rat penis, which may explain the role of TGF-beta in the pathogenesis of Peyronie's disease.

Antibody to GBV-C second envelope glycoprotein (anti-GBV-C E2): is it a marker for immunity?

The clinical significance of GB virus C (GBV-C E2) antibody is under investigation. The prevalence rates of GBV-C RNA and antibody to GBV-C E2 glycoprotein were determined in a population of 123 Egyptian anti-hepatitis C virus (HCV)-positive patients with chronic liver disease (CLD) who had not been treated previously with interferon. Sera were tested for GBV-C RNA by the LCx assay (Abbott Laboratories, North Chicago, IL), and for GBV-C E2 antibody by enzyme immunoassay. GBV-C RNA was present in 11.4% of patients. GBV-C E2 antibody was detected in 55.9% of GBV-C RNA-negative patients and in 2.2% of GBV-C RNA-positive patients (P = 0.006). GBV-C RNA was associated significantly with a history of schistosomiasis (relative risk [RR] = 5.83, 95% confidence interval [CI] 1.99-17.14, P < 0.005) but not with parenteral risk factors. The presence of GBV-C E2 antibody was not associated with age, gender, parenteral risk factors, schistosomal infection, or HCV viremia. The HCV genotype and level of viremia were similar in GBV-C anti-E2-positive and negative patients. There was a trend toward more severe histological disease with anti-E2 seropositivity (RR = 1.45, 95% CI 0.89-2.45, P = 0.11), an association which was independent of the evidence of schistosomiasis. It is concluded that GBV-C infection is common among HCV-infected Egyptian patients with CLD due to HCV infection. A significant negative correlation between the GBV-C viremia and GBV-C E2 antibody suggests that an antibody response is associated with viral clearance. This antibody response presumably occurs spontaneously, as none of the patients had received antiviral therapy. The unexpected association between GBV-C RNA and schistosomiasis suggests that nonparenteral or occult parenteral routes of GBV-C infection are likely to be important.

Peyronie's disease is associated with an increase in transforming growth factor-beta protein expression

PURPOSE

Transforming growth factor-beta (TGF-beta) has been implicated in many chronic fibrotic conditions such as pulmonary and hepatic fibrosis. We postulated that TGF-beta may play a role in the pathogenesis of Peyronie's disease.

MATERIALS AND METHODS

Tissues from the tunica albuginea of 30 Peyronie's disease patients (study group) and from 6 patients without Peyronie's disease, who had undergone penile prosthesis surgery for organic impotence (control group), were subjected to histological examination using Hart and trichrome stains and Western blotting for the detection of TGF-beta protein expression.

RESULTS

The results of these experiments demonstrate that all tissue from Peyronie's disease patients showed a variety of histological changes of the tunica, ranging from chronic inflammatory cellular infiltration to complete calcification and ossification of the tissues. The most prominent changes observed in the majority of patients were focal or diffused elastosis, fenestration and disorganization of the collagen bundles. TGF-beta1 protein expression was detected in 26 patients (86%), while only 7 (23%) and 5 (17%) patients showed TGF-beta2 and TGF-beta3 protein expression, respectively. One patient in the control group showed fibrosis of the tunica albuginea and protein expression of TGF-beta1 and TGF-beta2. This patient had undergone surgery for the revision of his prosthesis twice. Five patients from the control group showed normal histological patterns of the tunica albuginea and no protein expression for TGF-beta1, TGF-beta2 and TGF-beta3.

CONCLUSIONS

TGF-beta1 protein expression is significantly associated with Peyronie's disease, which may provide a new insight and the potential for the prevention and treatment of this disease.