Sustained influence of infections on prostate-specific antigen concentration: An analysis of changes over 10 years of follow-up

BACKGROUND

To extend our previous observation of a short-term rise in prostate-specific antigen (PSA) concentration, a marker of prostate inflammation and cell damage, during and immediately following sexually transmitted and systemic infections, we examined the longer-term influence of these infections, both individually and cumulatively, on PSA over a mean of 10 years of follow-up in young active duty U.S. servicemen.

METHODS

We measured PSA in serum specimens collected in 1995-7 (baseline) and 2004-6 (follow-up) from 265 men diagnosed with chlamydia (CT), 72 with gonorrhea (GC), 37 with non-chlamydial, non-gonococcal urethritis (NCNGU), 58 with infectious mononucleosis (IM), 91 with other systemic or non-genitourinary infections such as varicella; and 125-258 men with no infectious disease diagnoses in their medical record during follow-up (controls). We examined the influence of these infections on PSA change between baseline and follow-up.

RESULTS

The proportion of men with any increase in PSA (>0 ng/mL) over the 10-year average follow-up was significantly higher in men with histories of sexually transmitted infections (CT, GC, and NCNGU; 67.7% vs 60.8%, P = 0.043), systemic infections (66.7% vs 54.4%, P = 0.047), or any infections (all cases combined; 68.5% vs 54.4%, P = 0.003) in their military medical record compared to controls.

CONCLUSIONS

While PSA has been previously shown to rise during acute infection, these findings demonstrate that PSA remains elevated over a longer period. Additionally, the overall infection burden, rather than solely genitourinary-specific infection burden, contributed to these long-term changes, possibly implying a role for the cumulative burden of infections in prostate cancer risk.

Comparative evaluation of three FDA-approved HIV Ag/Ab combination tests using a genetically diverse HIV panel and diagnostic specimens

BACKGROUND

HIV Ag/Ab combination assays are recommended by CDC for routine screening and several HIV Ag/Ab combination tests are now FDA-approved. Maintaining high specificity and consistent sensitivity across diverse HIV strains is critical for these assays to accurately detect HIV infection and expedite delivery of patient results.

OBJECTIVES

To evaluate performance of three FDA-approved HIV tests: ARCHITECT HIV Combo (Abbott), ADVIA Centaur HIV Combo (Siemens) and BioPlex HIV Ag-Ab (Bio-Rad).

STUDY DESIGN

Sensitivity and specificity were evaluated using an extensive panel of 28 HIV infected human specimens and 17 cultured virus isolates representing multiple genotypes, 6 seroconversion panels, 4 human samples with acute infection, WHO p24 standard and 4020 clinical specimens.

RESULTS

The p24 limit of detection (LOD) for the WHO standard was 0.19IU/ml, 0.70IU/ml, and 1.77IU/ml in BioPlex, ARCHITECT, and Centaur respectively. The distribution of LODs across 15 HIV-1 isolates was substantially narrower in ARCHITECT (5-33pg/ml) than in BioPlex (11-198pg/ml) and Centaur (6-384pg/ml). All assays detected antibodies to the majority of HIV-1 and HIV-2 variants. However, reduced sensitivity was observed for Centaur in detection of antibodies to HIV-1 group M (CRF02_AG), O and N variants. BioPlex and ARCHITECT showed better seroconversion sensitivity than Centaur, detecting one bleed (3-7 days) earlier in 4 (BioPlex) and 3 (ARCHITECT) of 6 seroconversion panels. ARCHITECT demonstrated the highest specificity (99.90-100%) compared to BioPlex (99.80%) and Centaur (99.42%).

CONCLUSIONS

The overall performance of ARCHITECT and BioPlex was superior to Centaur, especially for detection of acute HIV infection.

Insight into infection-mediated prostate damage: Contrasting patterns of C-reactive protein and prostate-specific antigen levels during infection

BACKGROUND

To investigate mechanisms underlying our previous observation of a large rise in serum prostate-specific antigen, a marker of prostate pathology, during both sexually transmitted and systemic infections, we measured serum high-sensitivity C-reactive protein (hsCRP), a marker of systemic inflammation, in our previous case-control study of young, male US military members and compared our findings to those for PSA.

METHODS

We measured hsCRP before and during infection for 299 chlamydia, 112 gonorrhea, and 59 non-chlamydial, non-gonococcal urethritis (NCNGU) cases; before and after infection for 55 infectious mononucleosis (IM) and 90 other systemic/non-genitourinary cases; and for 220-256 controls.

RESULTS

Only gonorrhea cases were significantly more likely to have a large hsCRP rise (≥1.40 mg/L or ≥239%) during infection than controls (P < 0.01). However, gonorrhea, IM, and other systemic/non-genitourinary cases were more likely to have a rise of any magnitude up to one year post-diagnosis than controls (p = 0.038-0.077).

CONCLUSIONS

These findings, which differ from those for PSA, suggest distinct mechanisms of elevation for hsCRP and PSA, and support both direct (eg, prostate infection) and indirect (eg, systemic inflammation-mediated prostate cell damage) mechanisms for PSA elevation. Future studies should explore our PSA findings further for their relevance to both prostate cancer screening and risk.

Infectious mononucleosis, other infections and prostate-specific antigen concentration as a marker of prostate involvement during infection

Although Epstein-Barr virus has been detected in prostate tissue, no associations have been observed with prostate cancer in the few studies conducted to date. One possible reason for these null findings may be use of cumulative exposure measures that do not inform the timing of infection, i.e., childhood versus adolescence/early adulthood when infection is more likely to manifest as infectious mononucleosis (IM). We sought to determine the influence of young adult-onset IM on the prostate by measuring prostate-specific antigen (PSA) as a marker of prostate inflammation/damage among U.S. military members. We defined IM cases as men diagnosed with IM from 1998 to 2003 (n = 55) and controls as men without an IM diagnosis (n = 255). We selected two archived serum specimens for each participant, the first collected after diagnosis for cases and one randomly selected from 1998 to 2003 for controls (index), as well as the preceding specimen (preindex). PSA was measured in each specimen. To explore the specificity of our findings for prostate as opposed to systemic inflammation, we performed a post hoc comparison of other infectious disease cases without genitourinary involvement (n = 90) and controls (n = 220). We found that IM cases were more likely to have a large PSA rise than controls (≥ 20 ng/mL: 19.7% versus 8.8%, p = 0.027; ≥ 40% rise: 25.7% versus 9.4%, p = 0.0021), as were other infectious disease cases (25.7% versus 14.0%, p = 0.020; 27.7% versus 18.0%, p = 0.092). These findings suggest that, in addition to rising because of prostate infection, PSA may also rise because of systemic inflammation, which could have implications for PSA interpretation in older men.

Abstract A96: The influence of infectious mononucleosis on prostate-specific antigen concentration as a marker of prostate involvement during infection

Background: Although Epstein-Barr virus (EBV), a common gamma herpesvirus known to contribute to several cancers (e.g., Burkitt's lymphoma), has been detected in prostate tissue, results from the few epidemiologic studies of EBV infection and prostate cancer have been null. One possible reason for these null findings may be that not all EBV infections contribute to prostate cancer risk. For instance, for other proposed EBV-associated conditions, such as multiple sclerosis, infections acquired later in life (e.g., in adolescence or early adulthood) when EBV infection tends to manifest as infectious mononucleosis (IM) have been found to be more important for risk than those acquired earlier in life when EBV infection is typically asymptomatic. To begin to explore the importance of later-onset EBV infections for prostate carcinogenesis, we investigated the extent of prostate pathogenesis during adult-onset IM by measuring prostate specific antigen (PSA) concentration as a marker of prostate infection, inflammation, and cell damage in adult-onset IM cases and controls with stored serum in the Department of Defense Serum repository (DoDSR).

Methods: IM cases were men diagnosed with IM in 1998–2003 (n=55) and controls were a sample of men with no IM diagnoses from 1995–2006 (n=255). For each IM case, we selected two archived serum specimens from the DoDSR, one collected after their diagnosis (acute specimen, range: 1 day-3 years after diagnosis) and the first specimen collected immediately before their acute specimen (pre-acute specimen, range: 46 days-4 years before diagnosis). We also selected two specimens for each control, one collected from 1998–2003 (“acute”) and the first specimen collected immediately before their “acute” specimen (“pre-acute”). All specimens were anonymized before release from the DoDSR. We measured PSA in each of these stored specimens by the Access Hybritech PSA assay. We compared the absolute and relative change in PSA between the pre-acute and acute specimens for cases and controls using logistic regression and adjusting for age, race, and time between specimens.

Results: IM cases were significantly more likely to have a large increase in PSA between their pre-acute and acute specimens than controls. This finding was observed both when PSA increase was defined as a large absolute (≥0.4 ng/mL; 9.9% versus 2.7%, p=0.033) or relative rise (≥40%; 25.2% versus 8.9%, p=0.0021). Similar results were observed when men with any infectious disease or genitourinary diagnoses between their pre-acute and acute specimens were excluded.

Conclusions: Our findings suggest that EBV may infect the prostate and contribute to prostate inflammation and/or cell damage in some men with adult-onset IM. However, another interpretation of our findings that also warrants further investigation is the possibility of systemic inflammation-mediated PSA elevation. This alternate interpretation might have implications not only for a role of later-onset EBV infection in prostate carcinogenesis, but also for the specificity of PSA as a screening test for prostate cancer when used below the currently proposed age for screening initiation of 40 years. Funding: This study was funded by the Patrick C. Walsh Prostate Cancer Research Fund.

Citation Information: Cancer Prev Res 2011;4(10 Suppl):A96.

Prostate involvement during sexually transmitted infections as measured by prostate-specific antigen concentration

Background:

We investigated prostate involvement during sexually transmitted infections by measuring serum prostate-specific antigen (PSA) as a marker of prostate infection, inflammation, and/or cell damage in young, male US military members.

Methods:

We measured PSA before and during infection for 299 chlamydia, 112 gonorrhoea, and 59 non-chlamydial, non-gonococcal urethritis (NCNGU) cases, and 256 controls.

Results:

Chlamydia and gonorrhoea, but not NCNGU, cases were more likely to have a large rise (⩾40%) in PSA than controls (33.6%, 19.1%, and 8.2% vs 8.8%, P<0.0001, 0.021, and 0.92, respectively).

Conclusion:

Chlamydia and gonorrhoea may infect the prostate of some infected men.

The presence of circulating tumor cells does not predict extravesical disease in bladder cancer patients prior to radical cystectomy

OBJECTIVE

Due to imprecise clinical staging, the finding of extravesical and node-positive disease at the time of radical cystectomy (RC) for patients with clinically localized bladder cancer is not uncommon. Circulating tumor cells (CTCs) have been shown to be present in the peripheral blood of patients with metastatic urothelial carcinoma. The object of this study was to evaluate the ability of CTCs to predict extravesical disease in bladder cancer patients prior to RC.

MATERIALS AND METHODS

Peripheral blood samples from 43 patients with bladder cancer were evaluated using the CellSearch (Veridex, LLC, Raritan, NJ) CTC assay prior to RC. The sensitivity, specificity, and positive predictive value (PPV) of CTC status in predicting extravesical disease was calculated. Receiver operating characteristic (ROC) curves were generated to quantify the ability of CTCs to predict extravesical and node-positive disease.

RESULTS

CTCs were detected in 9 (21%) patients prior to RC. The sensitivity, specificity, and PPV of CTC status in predicting extravesical disease were 27%, 88% and 78%, respectively. The accuracy of CTC status in predicting extravesical (≥pT3 or node-positive) disease for the entire cohort was 0.576. In a model incorporating preoperative hydronephrosis, CTC status did not improve the predictive accuracy for extravesical disease (0.576 vs. 0.585, P = 0.915).

CONCLUSION

CTCs were detected in low numbers in a small percentage (21%) of patients prior to undergoing RC at our institution. CTC status was not a robust predictor of extravesical or node-positive disease in this cohort. CTC status is not likely to be a clinically useful parameter for directing therapeutic decisions in patients with ≤cT2 bladder cancer.

The RNA-binding and adaptor protein Sam68 modulates signal-dependent splicing and transcriptional activity of the androgen receptor

The RNA-binding protein Sam68 has been reported to be up-regulated in clinical cases of prostate cancer (PCa), where it is thought to contribute to cell proliferation and survival. Consistent with this, we observed over-expression of Sam68 in a panel of clinical prostate tumours as compared with benign controls. Since Sam68 is implicated in a number of signalling pathways, we reasoned that its role in PCa may involve modulation of the androgen receptor (AR) signalling cascade, which drives the onset and progression of PCa. We found that Sam68 interacts with the AR in vivo in LNCaP cells, and is dynamically recruited to androgen response elements within the promoter region of the prostate-specific antigen (PSA) gene. Based on its known functions and nuclear location, Sam68 might either: (a) co-regulate AR-dependent transcription positively or negatively; or (b) modulate AR-dependent alternative splicing by enhancing incorporation of a Sam68-responsive exon transcribed under the control of an androgen-responsive promoter. We tested these possibilities using functional assays. Both wild-type Sam68 protein and the Sam68(V229F) mutant, which is impaired in RNA binding, functioned as a ligand-dependent AR co-activator on an androgen-regulated reporter gene. In contrast, splicing of a Sam68-responsive variable exon, transcribed under control of an androgen-responsive promoter, was strongly repressed in the presence of AR and androgens. This splicing inhibition was reversed by ectopic expression of Sam68 but enhanced by Sam68(V229F). These results demonstrate that Sam68 has separable effects on AR-regulated transcriptional activity and alternative splicing, both of which may affect PCa phenotypes.

Cytokine profiling of prostatic fluid from cancerous prostate glands identifies cytokines associated with extent of tumor and inflammation

BACKGROUND

Cytokines are key mediators of inflammation that may relate to prostate cancer initiation and progression, and that may be useful markers of prostatic neoplasia and related inflammation. In order to better understand the relationship between cytokines and prostate cancer, we profiled cytokines in prostatic fluids obtained from cancerous prostate glands and correlated them to both cancer status and inflammatory grade.

METHODS

Prostatic fluid was collected from fresh radical prostatectomy specimens and analyzed by cytokine antibody microarray. For comparison, cases were selected from patients with either minimal or extensive cancer volume on final pathology. Among the cytokines with the greatest difference between the tumor volume groups, eight had their levels quantitated by ELISA. In addition, the grade of prostatic inflammation by neutrophils, macrophages and lymphocytes was scored for each case and examined for correlations with cytokine levels.

RESULTS

Among 174 cytokines analyzed, HGF was the most increased (6.57-fold), and along with IL18Bpa was significantly elevated in patients with extensive disease compared to those with minimal disease. IL17, GITR, and ICAM-1 were elevated in specimens with significant neutrophilic inflammation into gland lumina, and IL18Bpa, IL17, GITR, and ICAM-1 were elevated in specimens with significant lymphocytic inflammation in prostatic stroma.

CONCLUSIONS

Prostatic fluid cytokines were identified that may be useful for early cancer detection and prognostication efforts and for assessment of prostatic inflammation, particularly if they can be found not only in prostatic fluids obtained ex vivo, but in expressed prostatic secretions or urine samples from men with prostates still in situ.

The tumour-suppressor protein ASPP1 is nuclear in human germ cells and can modulate ratios of CD44 exon V5 spliced isoforms in vivo

The ASPP1 (Apoptosis Stimulating Protein of p53) protein is an important tumour-suppressor. We have detected a novel protein interaction between the human ASPP1 (hASPP1) protein and the predominantly nuclear adaptor protein SAM68. In the human testis, full-length endogenous hASPP1 protein is located in the nucleus like SAM68, predominantly within meiotic and postmeiotic cells. Mouse ASPP1 (mASPP1) protein is mainly expressed in the brain and testis. The interaction with nuclear SAM68 is likely to be restricted to human germ cells, since endogenous mASPP1 protein is exclusively cytoplasmic. The C-terminal region of hASPP1 efficiently targeted a fused GFP molecule to the nucleus, whereas the N-terminus of hASPP1 targeted GFP to the cytoplasm. In the context of the full-length molecule this cytoplasmic targeting sequence is dominant in HEK293 and Saos-2 cells, since full-length hASPP1-GFP is almost exclusively cytoplasmic. Despite its predominantly cytoplasmic location, we show that ASPP1-GFP expression in HEK293 cells can regulate the ratio of alternative spliced isoforms derived from a pre-mRNA regulated downstream of cytoplasmic signalling pathways, and our data suggest that ASPP1 may operate in this case downstream or parallel to RAS signalling pathways.

Sexually transmitted infections and prostatic inflammation/cell damage as measured by serum prostate specific antigen concentration

PURPOSE

Although inflammation and cell damage due to STIs are hypothesized to contribute to the later development of prostate disease, few clinical studies have been done to investigate the extent to which sexually transmitted agents infect and induce an inflammatory immune response in the prostate. We indirectly investigated this question by measuring serum PSA, a possible marker of prostatic inflammation and cell damage, in men with documented STIs.

MATERIALS AND METHODS

Archived serum specimens from young men with laboratory confirmed exudative STIs, including gonorrhea, chlamydia and trichomonosis, and young men with no STI diagnoses were identified in 2 prospective studies of patients at Baltimore City STI clinics, that is 84 in the STI Transmission and Acquisition Study, and 61 in the Mucosal Immunity Study. Serum specimens from visits before, during and after STI diagnoses in men with at least 1 exudative STI diagnosis and from all visits in men with no STI diagnoses were tested for total PSA concentration.

RESULTS

After combining the studies patients with STIs were more likely to have a 40% or greater increase in PSA than patients with no STI diagnoses (32% vs 2%, p <0.01).

CONCLUSIONS

These findings suggest that STIs may contribute to prostatic inflammation and cell damage in a subset of infected men. Further studies are warranted to replicate study findings and determine host and infection characteristics associated with large PSA increases.

Does Rbmy have a role in sperm development in mice?

The Y(d1) deletion in mice removes most of the multi-copy Rbmy gene cluster that is located adjacent to the centromere on the Y short arm (Yp). XY(d1) mice develop as females because Sry is inactivated, probably because it is now juxtaposed to centromeric heterochromatin. We have previously produced XY(d1)Sry transgenic males and found that they have a substantially increased frequency of abnormal sperm. Staining of testis sections with a polyclonal anti-RBMY antibody appeared to show a marked decrease of RBMY protein in the spermatids of XY(d1)Sry males compared to control males, which led us to suggest that this may be responsible for the increase in sperm anomalies. In the current study we sought to determine whether augmenting Rbmy expression specifically in the spermatids of XY(d1)Sry males would ameliorate the sperm defects. An expressing Rbmy transgene driven by the spermatid-specific mouse protamine 1 promotor (mP1Rbmy) was therefore introduced into XY(d1)Sry males. This failed to reduce the frequency of abnormal sperm. In the course of this study, a new RBMY antibody was generated that, in contrast to the original antibody, failed to detect RBMY in spermatid stages by immunostaining. The lack of RBMY was confirmed by western blotting of lysates from purified round spermatids and elongating spermatids. The implications of these results for the proposed role for RBMY in sperm development are discussed.

Variable photosynthetic characteristics in waste stabilisation ponds

Algae play several key roles in waste stabilisation ponds. A model has been developed to predict algal concentration in waste stabilisation ponds, in which the relationship between photosynthesis and underwater light availability is central. One equation was selected from several alternative expressions that describe this relationship. The selected equation consisted of four photosynthetic parameters. A field sampling programme was designed to investigate the relationships between the photosynthetic parameters and the pond environment. Although initial regression analyses were unsuccessful, distinct diurnal variations were revealed in two key photosynthetic parameters, related to an inverse variation in chlorophyll a concentration. This led to the derivation of a dynamic feedback hypothesis which challenges the classic assumption in algal modelling of constant photosynthetic parameters.

Mutations at the mitochondrial DNA polymerase (POLG) locus associated with male infertility

Human mitochondrial DNA polymerase, encoded by POLG, contains a polyglutamine tract encoded by a CAG microsatellite repeat. Analysis of POLG genotypes in different populations identified an association between absence of the common, ten-repeat allele and male infertility typified by a range of sperm quality defects but excluding azoospermia.

Teratogen update: Lyme disease

We reviewed the world literature concerning the reproductive effects of Lyme disease (LD). Borrelia burgdorferi, which is the etiology of LD, is a spirochete and, as such, may share the potential for causing fetal infection, which may occur in the setting of maternal spirochetemia. Information concerning the effects of gestational LD derives from case reports and series, epidemiologic studies, and experimental animal models. Although provocative, these studies fail to define a characteristic teratogenic effect. However, skin and cardiac involvement have predominated in some reports. Pregnancy wastage has been suggested primarily by animal studies. Gestational LD appears to be associated with a low risk of adverse pregnancy outcome, particularly with appropriated antibiotic therapy. Suggestions for management of clinical situations are presented.

Intratubular germ cell neoplasia: associated infertility and review of the diagnostic modalities

The incidence of testicular neoplasia has increased, and its early detection has become a pressing clinical issue. The strong association between male subfertility and risk of testicular neoplasia is consistent with the existence of common pathogenetic factors. Most forms of testicular germ tumors are believed to stem from a common precursor, intratubular germ cell neoplasia (ITGCN), also known as testicular carcinoma in situ. Identification of ITGCN cells in testicular biopsies, however, is a diagnostic challenge and markers are sorely needed to assist in the accurate identification of the lesion.

The contribution of RNA-binding motif (RBM) antibody to the histopathologic evaluation of testicular biopsies from infertile men

Testicular biopsies of infertile men are often characterized by mixed histologic patterns, with different types of spermatogenic impairments being found in adjacent seminiferous tubules. RNA-binding motif (RBM) is a nuclear protein expressed exclusively in the male germ cell line. We reasoned that RBM might be a useful marker to identify germ cells in testicular sections, particularly in biopsies with mixed histologic phenotype and small focal concentrations of spermatogenesis. Testicular biopsies from azoospermic men were immunohistochemically evaluated for RBM expression. RBM expression was detectable in spermatogonia, spermatocytes, and round spermatids in biopsies of men with obstructive azoospermia and normal spermatogenesis. No specific cell staining was shown in cases of Sertoli-cell-only (SCO) syndrome. In biopsies of patients with spermatogenic disorders, all the germ cells were stained up to and including the stage level of the arrest in spermatogenesis. This approach enabled identification of small focal concentrations of spermatogenesis in a biopsy previously classified as being SCO by hematoxylin and eosin staining. Thus, RBM can be a useful immunohistochemical marker for the specific identification of germ cells and provide greater accuracy in the histopathologic evaluation of testicular biopsies.

RBMY genes and AZFb deletions

Microdeletions of the AZFb region of the human Y chromosome usually result in severe consequences for spermatogenesis. AZFb contains at least four kinds of genes/gene families. These include a number of RBMY genes, which are clustered in the AZFb deletion interval. They are amongst the oldest genes on the mammalian Y chromosome, and are related to the gene encoding hnRNPG (RBMX) on the X chromosome. A retroposon-derived version of these genes is found on chromosome 11 that might replace the function of these genes during meiosis, during which time the X and Y chromosomes are transcriptionally inactivated. Each of these genes encodes proteins with an RNA binding motif, and interacts with more ubiquitously expressed proteins involved in pre-mRNA splice site selection. These findings imply that important pre-mRNA processing pathways might be disrupted in the germ cells of AZFb men.

An evolutionarily conserved germ cell-specific hnRNP is encoded by a retrotransposed gene

The gene encoding heterogeneous ribonucleoprotein (hnRNP) G recently has been mapped to the X chromosome. All mammals have a Y chromosome-encoded homologue of HNRNP G called RBMY, which is implicated with a role in male fertility and is a candidate for the azoospermia factor gene. We have identified a new member of this gene family, HNRNP G-T, and have mapped it as a single-copy gene on chromosome 11. This gene contains an uninterrupted open reading frame and no introns, consistent with derivation from a retroposon. However, unlike many retroposon-derived genes, HNRNP G-T is not a pseudogene. An antiserum raised to the conceptual reading frame of HNRNP G-T showed that it encodes a protein that is highly expressed in germ cells and in particular in the nuclei of meiotic spermatocytes. Surprisingly, although this antiserum was raised against human hnRNP G-T protein, it can also detect a similar protein in the testis of several mammals. This suggests that the protein is highly conserved and that the retrotransposition event generating the HNRNP G-T gene pre-dated at least the common ancestor of mouse and man. The existence of an additional testis-specific hnRNP G family member provides evidence for the importance of these proteins in normal germ cell development.

Absence of RBM expression as a marker of intratubular (in situ) germ cell neoplasia of the testis

RBM (RNA-binding motif) protein is a marker of male germ cells. This protein is encoded by the Azoospermia factor region-b (AZF-b) of the human Y chromosome and is expressed exclusively in the male germ cell line, that is, spermatogonia, spermatocytes, and round spermatids. The authors analyzed the expression of the RBM gene in germ cell tumors and in the seminiferous tubules in the vicinity of these tumors to identify the presence of IGCN. Sections from testicular germ cell tumors of 21 patients were stained with anti-RBM antibody by using an immunohistochemical method. Distal tubules showing spermatogenesis were immunopositive for RBM protein. All of the germ cell tumors studied were completely immunonegative for RBM. Defined areas of IGCN also showed an absence of RBM expression. Tubules with spermatocyte-like cells, which were expected to express RBM, did not express this protein. This result enabled the identification of tubules as being IGCN. RBM is a novel marker consistently expressed in normal male germ cells but not in malignant germ cell tumors or IGCN. Thus, the absence of RBM expression in germ cells provides a new diagnostic tool of preinvasive malignancy of the testis.

Maturation phenotype of Sertoli cells in testicular biopsies of azoospermic men

The involvement of Sertoli cells in different spermatogenic impairments has been studied by an immunohistomorphometric technique using cytokeratin-18 (CK-18) as a marker for immature Sertoli cells. CK-18 is known to be expressed in Sertoli cells during prenatal and prepubertal differentiation and is normally lost at puberty. Forty-nine azoospermic men were included in the current study. Quantitative measurements on testicular biopsies revealed the highest CK-18 expression in the mixed atrophy biopsies (22 men), a lower expression in the Sertoli cell-only (SCO) biopsies (12 men), and minimal residual staining in the group considered as representing normal spermatogenesis (six obstructive azoospermia patients). The cytokeratin immunopositive-stained tubules were associated either with arrest in spermatogenesis or with SCO. Examination of sections from nine men with microdeletions in the AZF region of the Y chromosome revealed that these men were either negative for CK-18 expression or showed only weak residual staining. This may suggest that the spermatogenic defect in the AZF-deleted men originates in the germ cell and has no impact on Sertoli cell maturation. The cause that determined the spermatogenic defect in the other cases of male infertility with high CK-18 expression may have damaged both the Sertoli and the germ cells.

A mammalian germ cell-specific RNA-binding protein interacts with ubiquitously expressed proteins involved in splice site selection

RNA-binding motif (RBM) genes are found on all mammalian Y chromosomes and are implicated in spermatogenesis. Within human germ cells, RBM protein shows a similar nuclear distribution to components of the pre-mRNA splicing machinery. To address the function of RBM, we have used protein-protein interaction assays to test for possible physical interactions between these proteins. We find that RBM protein directly interacts with members of the SR family of splicing factors and, in addition, strongly interacts with itself. We have mapped the protein domains responsible for mediating these interactions and expressed the mouse RBM interaction region as a bacterial fusion protein. This fusion protein can pull-down several functionally active SR protein species from cell extracts. Depletion and add-back experiments indicate that these SR proteins are the only splicing factors bound by RBM which are required for the splicing of a panel of pre-mRNAs. Our results suggest that RBM protein is an evolutionarily conserved mammalian splicing regulator which operates as a germ cell-specific cofactor for more ubiquitously expressed pre-mRNA splicing activators.

RBMY, a probable human spermatogenesis factor, and other hnRNP G proteins interact with Tra2beta and affect splicing

The RBMY gene family is found on the Y chromosome of all mammals, and microdeletions are strongly associated with infertility in men. RBMY expresses RBM only in the nuclei of germ cells, whereas its X chromosome homologue, RBMX, expresses hnRNP G ubiquitously. We show here that RBM, hnRNP G and a novel testis-specific relative, termed hnRNP G-T, interact with Tra2beta, an activator of pre-mRNA splicing that is ubiquitous but highly expressed in testis. Endogenous hnRNP G and Tra2beta proteins are associated in HeLa nuclear extracts. RBM and Tra2beta co-localize in two major domains in human spermatocyte nuclei. Phosphorylation enhanced the interaction and reduced competing RNA binding to the interaction domains. Incubation with the protein interaction domain of RBM inhibited splicing in vitro of a specific pre-mRNA substrate containing an essential enhancer bound by Tra2beta. The RNA-binding domain of RBM affected 5' splice site selection. We conclude that the hnRNP G family of proteins is involved in pre-mRNA splicing and infer that RBM may be involved in Tra2beta-dependent splicing in spermatocytes.

Splicing and the single cell

The selection of alternative splice sites is an important component of cell-specific gene regulation in eukaryotic cells. Use of splice sites can be positively and negatively regulated, and often physiologically appropriate splice site choice is achieved by a balance of the two. RNA elements controlling splice site choice are found in both exons and introns, and these determine management by the cellular splicing machinery. However, the molecular basis of how the splicing machinery responds to these signals in different cells is somewhat of a paradox. Thus far the identified proteins which bind to tissue/cell-specific regulatory elements in mammals are expressed in many different tissues, and not just in the regulating tissue. Potential tissue-specific splicing regulators have been identified by non-biochemical means. However, alternative splicing choices are likely to be affected by subtle differences in the splicing machinery in different cells. In this review I suggest that one important factor is the ratio of proteins in different nuclear compartments, which might be established in a cell type specific fashion.

Effect of cysteine substitutions on the topology of the S4 segment of the Shaker potassium channel: implications for molecular models of gating

1. The gating properties of voltage-gated potassium channels are largely determined by the amino acid sequence of their S4 segments. To investigate the nature of S4 movement during gating, we introduced single cysteines into the S4 segment of the Shaker potassium channel and expressed the mutants in Xenopus oocytes. We then measured the conductance-voltage (g-V) relationships and the rate and the voltage dependence of movement of the engineered cysteines, using p-chloromercuribenzene sulphonate (pCMBS) as a probe. 2. Mutation of charged residues at positions 362, 365 and 368, but not the uncharged residues (positions 360, 361, 363, 364 and 366), to cysteines shifted the g-V relationships to more positive potentials. Mutant channels in which cysteines replaced the charged residues at positions 362 and 365 (R362C and R365C) reacted faster with pCMBS than those in which cysteines were introduced in place of uncharged residues at positions 360 and 361 (I360C and L361C). Furthermore, the R365C mutant channel reacted with pCMBS even at hyperpolarised (-120 mV) potentials. Currents expressed by the doubly mutated R365S/V367C and R368S/V367C channels, but not the singly mutated V367C channel, were inhibited by pCMBS. Moreover, the R368C mutant channel was also affected by pCMBS. 3. Voltage dependence of block by pCMBS (2 min exposure) was steeper for L366C than for L361C and V363C mutant channels (effective charge 2.19, 1. 41 and 1.45, respectively). The voltage dependence of the pCMBS effect was also shifted to more depolarising potentials the deeper in the membrane the position of the residue mutated to cysteine (voltages for half-maximal effect -107, -94 and -73 mV for positions 361, 363 and 366, respectively). 4. Our data show firstly that charge-neutralising mutations in S4 alter the topology of this region such that the membrane-spanning portion of S4 is reduced. Secondly, our data for the other mutant channels suggest that S4 might move in at least two sequential steps, and can move up to its maximal limit even at the resting potential of the cell.

T-STAR/ETOILE: a novel relative of SAM68 that interacts with an RNA-binding protein implicated in spermatogenesis

RBM is an RNA-binding protein encoded on the Y chromosome in mammals and is expressed only in the nuclei of male germ cells. Genetic evidence from infertile men implicates it in spermatogenesis, but its function is unknown. Of a number of potential partners for RBM identified by a yeast two-hybrid screen with testis cDNA, the most frequent isolates encoded a novel RNA-binding protein, termed T-STAR, that is closely related to SAM68, an Src-associated protein of unknown function. The mouse homologue was also cloned and designated étoile. It mapped to chromosome 15, while T-STAR mapped to the syntenic region on human chromosome 8. T-STAR/étoile is expressed primarily in the testis; in rat germ cells, the expression of both T-STAR/étoile and SAM68 is regulated during meiosis. Transfection of T-STAR/étoile fused with green fluorescent protein into HeLa cells caused an accumulation of protein in a novel compartment of the nucleus, adjacent to the nucleolus but distinct from the peri-nucleolar compartment. RBM and other hnRNP G family members are candidate downstream targets for regulation by T-STAR/ETOILE and SAM68.

Understanding the genes involved in spermatogenesis: a progress report

OBJECTIVE

To review the current literature on genes known to affect fertility in the human and mouse.

DESIGN

A literature review was performed and key articles were chosen for focus in the areas of genes with effects only on spermatogenesis and oogenesis, with an emphasis on Y-chromosome-encoded gene families and spermatogenesis. In addition, studies describing genes deleted in transgenic mice were incorporated.

RESULT(S)

Several gene families on the Y chromosome are implicated in spermatogenic failure, but the link between the genetic lesion and the resulting defect is unclear. Many mouse genes involved in repair and DNA damage monitoring have specific effects on gametogenesis in and around meiosis.

CONCLUSION(S)

Many genes are involved only in gametogenesis, and some of these are beginning to be understood in terms of their functions. An even larger number of genes is required for gametogenesis, and other functions and mouse models give insights important for human disease.

Dynamic changes in the subnuclear organisation of pre-mRNA splicing proteins and RBM during human germ cell development

RBM is a germ-cell-specific RNA-binding protein encoded by the Y chromosome in all mammals, implying an important and evolutionarily conserved (but as yet unidentified) function during male germ cell development. In order to address this function, we have developed new antibody reagents to immunolocalise RBM in the different cell types in the human testis. We find that RBM has a different expression profile from its closest homologue hnRNPG. Despite its ubiquitous expression in all transcriptionally active germ cell types, RBM has a complex and dynamic cell biology in human germ cells. The ratio of RBM distributed between punctate nuclear structures and the remainder of the nucleoplasm is dynamically modulated over the course of germ cell development. Moreover, pre-mRNA splicing components are targeted to the same punctate nuclear regions as RBM during the early stages of germ cell development but late in meiosis this spatial association breaks down. After meiosis, pre-mRNA splicing components are differentially targeted to a specific region of the nucleus. While pre-mRNA splicing components undergo profound spatial reorganisations during spermatogenesis, neither heterogeneous ribonucleoproteins nor the transcription factor Sp1 show either developmental spatial reorganisations or any specific co-localisation with RBM. These results suggest dynamic and possibly multiple functions for RBM in germ cell development.

Mouse homologues of the human AZF candidate gene RBM are expressed in spermatogonia and spermatids, and map to a Y chromosome deletion interval associated with a high incidence of sperm abnormalities

An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.

The molecular genetics of male infertility

Spermatogenesis is an elaborate process involving both cell division and differentiation, and cell-cell interactions. Defects in any of these processes can result in infertility, and in some cases these can be genetic in cause. Mapping experiments have defined at least three regions of the human Y chromosome that are required for normal spermatogenesis. Two of these contain the genes encoding the RNA binding proteins RBM and DAZ, suggesting that the control of RNA metabolism is likely to be an important control point for human spermatogenesis. A similar analysis in mice has shown that at least two regions of the mouse Y chromosome are essential for spermatogenesis. Both genetic and reverse genetic approaches have been used to identify mouse autosomal genes required for spermatogenesis. These studies have shown that genes in a number of different pathways are essential for normal spermatogenesis, and also provide putative models of human infertility.

Expression of RBM in the nuclei of human germ cells is dependent on a critical region of the Y chromosome long arm

The association of abnormal spermatogenesis in men with Y chromosome deletions suggests that genes important for spermatogenesis have been removed from these individuals. Recently, genes encoding two putative RNA-binding proteins (RBM and DAZ/SPGY) have been mapped to two different regions of the human Y chromosome. Both of these genes encode proteins that contain a single RNA recognition motif and a (different) internally repeating sequence. Y-linked RBM homologues are found in all mammalian species. We have raised an antiserum to RBM and used it to show that RBM is a nuclear protein expressed in fetal, prepubertal, and adult male germ cells. The distribution of RBM protein in the adult correlates with the pattern of transcriptional activity in spermatogenesis, suggesting that RBM is involved in the nuclear metabolism of newly synthesized RNA. RBM sequences are found on both arms of the Y chromosome making genotype-phenotype correlations difficult for this gene family. To address the location of the functional genes and the consequences of their deletion, we examined a panel of men with Y chromosome deletions and known testicular pathologies using this antiserum. This approach enabled us to map a region of the Y chromosome essential for RBM expression. In the absence of detectable RBM expression we see stages of germ cell development up to early meiosis, but not past this point into the haploid phase of spermatogenesis.

Yeast pre-mRNA is composed of two populations with distinct kinetic properties

As an approach to the study of yeast pre-mRNA splicing in vivo, we have examined properties of transcripts derived from a gal-UAS intron-containing fusion gene encoding RP51A and a series of its derivatives. RNA half-life measurements were carried out after transcription initiation was blocked by the addition of glucose. Pre-mRNA encoded by GalRP51A decayed with a half-life of approximately 6 min and was substantially polyadenylated, and transcripts derived from a nonspliced version of the same gene decayed with a similar half-life ( approximately 4 min). A comparison of the steady-state levels of these two transcripts suggests that the bulk of GalRP51A pre-mRNA is processed much more rapidly, with an average lifetime of about 2 s. We propose that this inferred population of rapidly processed molecules is spliced cotranscriptionally and that it is the principal precursor to GalRP51A mRNA. Although the pre-mRNA molecules detected are therefore unlikely to be the major splicing precursors, an in vivo assay suggests that they are likely to have bound splicing factors. They must then be spliced much more slowly than most primary transcripts, or not spliced at all and then degraded through a different cellular pathway. As a result of its comparatively long lifetime, this minor fraction of the pre-mRNA population makes up the majority of the steady-state level of GalRP51A pre-mRNA.

An RBM homologue maps to the mouse Y chromosome and is expressed in germ cells

We have isolated a murine homologue of the human Y-linked RBM genes (previously termed YRRM), a gene family implicated in spermatogenesis and which encodes proteins containing an RNA recognition motif. A number of very similar copies of this gene (called Rbm) are present in the mouse. These mouse homologues are also Y-encoded, mapping on the short arm of the chromosome, proximal to Sry. Expression is confined to the testis, specifically the germ line on the basis of lack of expression in the germ-line negative testes of adult sex-reversed mice. The timing of Rbm transcription is regulated, with fetal message levels reaching a peak at 15 d.p.c. Transcripts are clearly detectable by 4 days after birth and reach their highest level at 14 d.p.p. which is the time at which the Y chromosome condenses during meiotic prophase. These results suggest that Rbm is functionally involved in germline RNA metabolism.

Spatial consequences of defective processing of specific yeast mRNAs revealed by fluorescent in situ hybridization

This work introduces the first use of fluorescent in situ hybridization (FISH) to detect the distribution of specific transcripts in Saccharomyces cerevisiae. We have applied this technique to analysis of reporter transcripts from a single, integrated copy, or multicopy plasmids. We have evaluated the effect of splice site deletions or the presence or absence of a terminator/cleavage site and demonstrated that both splicing and polyadenylation affect the export of these transcripts from the nucleus to the cytoplasm. Moreover, we show that the exported pre-mRNAs are substrates for nonsense codon-mediated decay through the UPF1 pathway. The work presented here demonstrates that the spatial distribution of transcripts will also be an important component of yeast RNA metabolism.

mRNA nuclear export

The export of mRNA from the nucleus to the cytoplasm is an essential step in the expression of genetic information in eukaryotes. It is an energy-dependent process and involves transport across the nuclear pores. It requires both cis-acting ribonucleoprotein particle signals and specific trans-acting factors. Although much remains to be learned, recent information has begun to define this pathway at both the cellular and biochemical levels and indicates that it is used as a key regulatory step by several viruses.

A yeast splicing factor is localized in discrete subnuclear domains

Digital imaging microscopy has been used to visualize the splicing protein PRP6p and three other yeast nuclear proteins. The results show that PRP6p is uniquely localized to discrete subnuclear regions. A combination of cytological and biochemical assays suggests that these sites can be saturated when the protein is overexpressed and likely correspond to the location of U4/U6 snRNPs. The observations indicate that some splicing components are located in discrete subregions of the yeast nucleus, similar to the situation described for the mammalian nucleus.

Depressive characteristics of sexually abused children

Allen and Tarnowski (1988) identified a pattern of depressive characteristics that distinguished physically abused from nonabused children. The present study attempted to extend the generality of these findings to sexually abused children. Sexually abused and nonabused children were compared on measures of depression, hopelessness, and self-esteem. Results indicated that while sexually abused children self-reported more depressive symptoms in comparison to nonabused controls, that these differences were not statistically significant and failed to replicate the findings noted for physically abused children.

Importance of alignment between local DC magnetic field and an oscillating magnetic field in responses of brain tissue in vitro and in vivo

The frequency dependence of the electric and magnetic (EM)-field-induced release of calcium ions from an in vitro brain tissue preparation has been shown to be a function of the density of the local DC magnetic field (Bdc). In this study, we demonstrate that the relative orientation of the Bdc and the magnetic component (Bac) of a 315-Hz EM signal (15 Vrms/m and 61 nTrms) are crucial for the induced release to be observed. The induced release occurs only when the Bdc and the Bac are perpendicular, and not when they are parallel. This finding is consistent with a magnetic resonance-like transduction mechanism for the conversion of EM energy into a physicochemical change, and contrasts with the requirement for parallel Bdc and Bac components in the diatom-mobility experiments of Smith et al. A review of the exposure conditions in the rat behavioral experiments conducted by Thomas et al. identifies unhydrated calcium and zinc ions as alternatives to lithium ions as candidates for interaction under parallel magnetic-field orientations but fails to reject perpendicular orientations as an alternative basis for the phenomenon. Investigators that attempt to confirm the rat behavioral experiments should be aware of the conflicting exposure conditions that can be assumed to be operative, and they should design their experiments to test all conditions accordingly.

Mutually exclusive synthetic pathways for sea urchin mitochondrial rRNA and mRNA

The structure and abundance of mitochondrial transcripts in sea urchin embryos were investigated by a combination of RNA blot-hybridization, S1 mapping, and primer extension assays. Between the egg and blastula stages, the relative abundance of mitochondrial rRNAs declined slightly, while that of mitochondrial mRNAs increased up to 10-fold. Fine mapping of the termini of the rRNAs and of the adjacent transcripts indicated that, although they appeared to be butt-joined at their 5' ends to the upstream transcripts, tRNA-Phe 5' to the small subunit (12S) rRNA and NADH dehydrogenase subunit 2 mRNA 5' to the large subunit (16S) rRNA, respectively, their 3' ends were found to overlap the 5' ends of the downstream transcripts. 12S rRNA was found to extend 7 to 13 nucleotides into the sequence of tRNA-Glu; 16S rRNA was shown to terminate 3 to 5 nucleotides inside the coding region of cytochrome oxidase subunit 1 (COI) and 8 to 10 nucleotides from the mapped 5' end of COI mRNA. The rRNAs and the downstream transcripts must therefore be synthesized by distinct pathways, either by alternative processing of the same primary transcript(s) or by processing of different precursors. In either case, the events which select the ribosomal 3' ends preclude the production of functional transcripts of the downstream genes from the same precursor molecule. No developmental alterations in transcript structure were detected. We propose that mitochondrial RNA levels are regulated in early development by the selection of alternate and mutually exclusive RNA-processing pathways.

Nucleotide sequence and gene organization of sea urchin mitochondrial DNA

The 15,650 base-pair mitochondrial genome of the sea urchin Strongylocentrotus purpuratus has been cloned and sequenced. It exhibits a novel organization that suggests the primacy of post-transcriptional gene regulation. The same 13 polypeptides, two rRNAs and 22 tRNAs are encoded as in other animal mitochondrial DNAs, but are organized with extreme economy; non-coding information between genes is almost completely absent, some stop codons are generated post-transcriptionally and tRNA sequences are interspersed between only a minority of other structural genes. The genome uses a variant genetic code, in which AAA specifies asparagine, ATA isoleucine, TGA tryptophan and AGN serine, and has an unusual pattern of codon bias. The order of genes shows several differences from that of vertebrates. The genes for the large (16 S) ribosomal RNA and for NADH dehydrogenase subunit 4L (ND4L) are in different positions, located respectively between those encoding ND2 and cytochrome oxidase subunit I (COI) and between COI and COII. This organization is conserved amongst at least four regular echinoids diverging by some 225 million years. Most tRNA genes are also in different positions. The only long unassigned sequence in the genome (121 base-pairs) is located within a cluster of 15 tRNA genes. It contains elements resembling some of those found in the displacement (D) loop of vertebrate mtDNAs, notably polypurine/polypyrimidine tracts that may play a role in regulating transcription and the initiation of replication. The separation of the ribosomal RNA genes from each other and from the putative control region imposes special demands on the transcription of the genome.

Influence of electromagnetic fields on the efflux of calcium ions from brain tissue in vitro: a three-model analysis consistent with the frequency response up to 510 Hz

The frequency dependence of electromagnetic field-induced calcium-ion efflux from chicken brain tissues has been examined at 15-Hz intervals over the range 1-510 Hz. The electric field component was 15 Vrms/m and the magnetic component varied between 59 and 69 nTrms. No patterns of response as a function of frequency could be readily discerned when the differences in mean efflux values between exposed and sham samples were compared. However, the calculated P-value, a function that combines at each frequency the difference between the means of the exposed and sham groups with the variance of each group, does provide a basis for hypothesizing the existence of three frequency-dependent patterns in the data. One pattern includes all the highly significant (P less than .01) responses which occur between 15 and 315 Hz, at 30-Hz intervals; two independent trials at 165 Hz, giving nonsignificant responses (P greater than .5), break this pattern into two groups of five frequencies each, which is contrary to the expected result for a simple Lorentz-force interaction. However, another pattern of significant results at 60, 90, and 180 Hz, but not at 300 Hz, is consistent with a Lorentz-force model. A third pattern, composed of only one significant response at 405 Hz, is very close to the resonance predicted on a linear extrapolation from high-frequency data for 13carbon atoms. This hypothetical ordering of the frequency-response profile provides the basis for future experimental designs to test each possible interaction model and for their connection to the calcium-ion efflux endpoint.

Functional vs. organic pain: a meaningful distinction?

This study examined the statistical and clinical validity of the distinction frequently made between "functional" pain and "real" pain. Earlier work has relied on the MMPI exclusively and results have been inconclusive, yet the distinction continues to be made and treatment is recommended on the basis of the label. Sixty-seven chronic back pain patients were administered questionnaires that assessed quantity and quality of depression, dimensions of illness behavior, and psychogenic attitudes. Scores of chronic pain patients were compared to normal subjects, and results indicate that the pain subjects experienced high levels of depression, anxiety, and social alienation. However, organic pain subjects did not differ from subjects with no organic findings. The authors suggest that the distinction between organic and functional pain be discarded in favor of an approach that assesses current emotional stressors and available coping mechanisms.

Control of energy absorption rate in transmission line radiofrequency exposure systems

A frequent problem in the radiofrequency (RF) irradiation of experimental animals in health effects studies is the temporal variation of the specific absorption rate (SAR) with animal movement. An RF power controller that regulates the energy absorption rate has been designed for use with transmission line exposure systems that utilize the power difference method to monitor the SAR. The controller operates by altering the incident power to the exposure cell in order to compensate for the change in RF energy absorption rate that is due to animal motion. A circuit diagram is presented as well as experimental data under three conditions of exposure. The controller is effective in maintaining the mean value of energy absorption rate at the setpoint value even for the case of a highly active animal.

Mastery, stress, and coping in marriage among chronic pain patients

Marital stress, strain, and coping strategies were investigated in chronic pain patients by administering the Problems of Everyday Life Interview (PEL) to 55 married chronic pain patients. Subjects were assigned to either limited, moderate, or heightened mastery groups based upon PEL mastery scores. The heightened mastery group reported less marital strain, less marital stress, more use of negotiation, less use of selective ignoring, and less use of manage-stress coping strategies than either limited mastery or moderate mastery groups. There were no significant differences between limited mastery and moderate mastery groups on any variables measured. There were no differences between mastery groups on advice seeking. The effects of mastery as a mediator of coping and stress are discussed, as well as the advisability of incorporating treatments that specifically address feelings of lack of control over stressful events into chronic pain programs, especially when marital problems are identified.