Surgery

ObjectiveOpsonization of apoptotic cells by autoantibodies bound to surface membrane–translocated La/SSB antigens may initiate tissue damage in the setting of congenital heart block. By injecting pregnant mice with human anti-La antibodies, we previously demonstrated the formation of IgG–apoptotic cell complexes in the developing mouse fetus; however, the binding of anti-La antibodies to human-specific epitopes could not be addressed. Accordingly, the objective of the current study was to delineate the epitope specificity of human La antibodies that are exposed on the surface of apoptotic cells.Opsonization of apoptotic cells by autoantibodies bound to surface membrane–translocated La/SSB antigens may initiate tissue damage in the setting of congenital heart block. By injecting pregnant mice with human anti-La antibodies, we previously demonstrated the formation of IgG–apoptotic cell complexes in the developing mouse fetus; however, the binding of anti-La antibodies to human-specifi...

The prostate-specific antigen (PSA) gene, also known as KLK3, is located on the long arm of chromosome 19. This gene encodes for PSA, a widely used diagnostic marker for prostate cancer. PSA is a serine protease enzyme produced by the epithelial cells of the prostate ...

Narcolepsy is widely believed to have an autoimmune basis, but conventional immunological approaches have failed to detect a serum autoantibody marker. Since cholinergic hyperactivity is a feature of narcolepsy-cataplexy, we transferred IgG from nine patients with narcolepsy and nine healthy controls to mice and assessed the effect on smooth muscle contractile responses to cholinergic stimulation. IgG from all narcolepsy patients significantly enhanced bladder contractile responses to the muscarinic agonist carbachol and to neuronally released acetylcholine compared with control IgG (p<0.0001), whereas contraction of the sympathetically innervated vas deferens was unaltered. Our findings provide direct evidence for the autoimmune hypothesis of narcolepsy.

There is increasing evidence that sensitization of the androgen receptor (AR) signaling pathway contributes to the failure of androgen ablation therapy for prostate cancer, and that direct targeting of the AR may be a useful therapeutic approach. To better understand how AR function ...

The role of cardiocytes in physiologic removal of apoptotic cells and the subsequent effect of surface binding by anti-SSA/Ro and -SSB/La antibodies was addressed. Initial experiments evaluated induction of apoptosis by extrinsic and intrinsic pathways. Nuclear injury and the ...

Although up to 30% of men who undergo radical prostatectomy for clinically organ-confined prostate cancer will relapse with disseminated disease, currently it is not possible to predict these patients. Androgen receptor (AR) immunoreactivity in stromal and epithelial compartments of tumor foci was evaluated by video image analysis in 53 radical prostatectomy specimens. Kaplan-Meier and Cox Regression analyses were used to determine whether AR immunostaining was related to rate and risk of relapse, respectively. Ninety-eight percent (52/53) of the tumors contained AR positive malignant epithelial cells. Kaplan-Meier analysis indicated that patients with high AR levels (>64% AR positive nuclear area) in the malignant epithelial cells or low AR levels (<or=45% AR positive nuclear area) in the peritumoral stroma cells, were more likely to relapse earlier following radical prostatectomy. The shortest time to relapse and the highest relapse rate was for patients with both high AR in the malignant epithelial cells and low AR in the peritumoral stromal cells. These findings suggest that AR is an important determinant of disease relapse in early stage prostate cancer, and that altered AR levels in the malignant epithelial cells or in the peritumoral stroma is indicative of non-organ confined prostate cancer.

High grade prostatic intraepithelial neoplasia (HGPIN) is a putative pre-malignant lesion of the prostate. While apolipoprotein-D (Apo-D), an androgen-regulated hydrophobic transporter protein, is expressed in prostate tumors, its expression in HGPIN is unknown. Immunoreactivity for Apo-D and another androgen-regulated protein, prostate specific antigen (PSA), was investigated in 64 radical prostatectomy tissues by video image analysis. Eighty two percent of prostatectomy specimens demonstrated moderate to strong Apo-D immunoreactivity in areas of HGPIN. In comparison, weak Apo-D immunoreactivity was observed in non-malignant areas in only 24% of specimens. The median (range) percentage cellular area of HGPIN immunopositive for Apo-D (9.7%, 0-42.9), and the cellular concentration of Apo-D (MIOD 3.1, 0-13.3), were intermediate between that of normal (area 0%, 0-53.5%, MIOD 0, 0-12.6) and early stage prostate cancer tissues (area 29.2%, 0-90.8%, MIOD 6.7, 0-28.1). This increase in Apo-D expression from non-malignant, through HGPIN to prostate cancer was statistically significant (P < 0.001), and contrasted with the decrease observed in PSA staining between adjacent areas of normal glands, HGPIN, and cancer (P = 0.026). The presence of high levels of immunoreactive Apo-D in HGPIN and prostate cancer, but not in non-malignant epithelial cells, is consistent with HGPIN being an intermediate lesion in the transition to prostate cancer, and suggests that cellular Apo-D expression is a marker of malignant transformation of the prostate.

We have shown previously that the cII gene product of the non-lambdoid temperate bacteriophage 186 is required for the establishment of lysogeny. We show here that CII, a potential helix-turn-helix DNA-binding protein, establishes lysogeny by activating a promoter (pE) ...

A single-copy chromosomal reporter system was used to measure the intrinsic strengths and interactions between the three promoters involved in the establishment of lysogeny by coliphage 186. The maintenance lysogenic promoter p L for the immunity repressor gene cI is intrinsically ∼20-fold weaker than the lytic promoter p R. These promoters are arranged face-to-face, and transcription fromp L is further weakened some 14-fold by the activity of p R. Efficient establishment of lysogeny requires the p E promoter, which lies upstream of p L and is activated by the phage CII protein to a level comparable to that ofp R. Transcription of p Eis less sensitive to converging p Rtranscription and raises cI transcription at least 55-fold. The p E promoter does not occludep L but inhibits lytic transcription by 50%. This interference is not due to bound CII preventing elongation of the lytic transcript. The p E RNA is antisense to the anti-immune repressor gene apl, but any role of this in the e...

BACKGROUND Alterations in the control of gene expression is a key event in neoplastic transformation. Investigating the expression of transcription factors such as homeodomain proteins may therefore allow better characterization of molecular mechanisms underlying the transformation process. MATERIALS AND METHODS Expression of homeodomain proteins DLX4 and HB9 was detected by RT-PCR and immunohistochemically in 24 breast tumors and their corresponding non-malignant tissue. RESULTS Although the percentage of nuclei expressing both DLX4 (p = 0.001) and HB9 (p = 0.0001) is increased in breast carcinoma, their intensity of nuclear staining is decreased compared to non-malignant nuclei. Furthermore HB9 nuclear immunoreactivity decreased progressively with increasing tumor grade (p = 0.001). CONCLUSION These data suggest that the reduction in malignant nuclear DLX4 immunoreactivity is an earlier event in breast carcinogenesis than the progressive loss of HB9 expression observed with increa...

Background: The ELAC2 gene has been proposed to be a prostate cancer susceptibility gene and is being referred to as HPC2, in part because three case–control studies suggested that two common polymorphisms (Ser217Leu and Ala541Thr) are associated with risk. However, four subsequent larger studies have not confirmed this association. In five of the seven total studies, subject selection was influenced by prostate-specific antigen (PSA) levels. We examined the association and possible effect of subject selection in a larger study and a meta-analysis. Methods: In a population-based study in Australia, 825 case patients and 732 control subjects were genotyped for the Ser217Leu and Ala541Thr polymorphisms of ELAC2. Odds ratios (ORs) for prostate cancer were estimated by unconditional logistic and polytomous regression. A meta-analysis was conducted combining our data with those from seven published studies. The association of genotype with the logarithm of plasma PSA levels in control su...

We describe a novel ERBB1/EGFR somatic mutation (p. C329R; c.985 T > C) identified in a patient with JAK2 V617F Polycythaemia Vera (PV). This substitution affects a conserved cysteine residue in EGFR domain 2 and leads to the formation of a ligand-independent covalent receptor dimer, associated with increased transforming potential. Aberrant signalling from the EGFR C329R receptor is cell typedependent and in the TF1.8 erythroid cell line expression of this mutant suppresses EPO-induced differentiation. Clonal analysis shows that the dominant JAK2 V617F-positive clone in this PV patient harbors EGFR C329R , thus this mutation may contribute to clonal expansion. Somatic mutations affecting other ERBB and related receptor tyrosine kinases are observed in myeloproliferative neoplasms (MPN), and we show elevated EGFR levels in MPN samples, consistent with previous reports. Thus activation of this group of receptors, via multiple mechanisms, may contribute to clonal growth and survival of the JAK2 V617F disease clone in MPN.

The purpose of this study was to identify homeobox genes expressed in the human colon and to determine whether their expression levels were altered between matched non-malignant and malignant colon tissues. Homeobox genes expressed in colon tissue were identified by reverse transcription polymerase chain reaction (RT-PCR). Antibodies were raised to the homeodomain proteins DLX4, HB9 and HB24 and immunohistochemistry was performed on 3 moderately-differentiated tumors and their corresponding non-malignant colon tissue samples. The RT-PCR screen identified expression of DLX4, HB9, HB24 and MSX2 in the normal colon. Immunoaffinity purified polyclonal antisera raised against DLX4, HB9 and HB24 detect specific immunoreactivity in glandular epithelial cells, stromal cells of the lamina propria but not in the submucosa. Nuclear epithelial immunoreactivity of all three antibodies decreased in moderately-differentiated tumors compared to the corresponding matched non-malignant mucosa. These ...

Opsonization of apoptotic cells by autoantibodies bound to surface membrane-translocated La/SSB antigens may initiate tissue damage in the setting of congenital heart block. By injecting pregnant mice with human anti-La antibodies, we previously demonstrated the formation of IgG-apoptotic cell complexes in the developing mouse fetus; however, the binding of anti-La antibodies to human-specific epitopes could not be addressed. Accordingly, the objective of the current study was to delineate the epitope specificity of human La antibodies that are exposed on the surface of apoptotic cells. We used fluorescence microscopy and flow cytometry to assess the binding of human anti-La antibodies affinity purified against immunodominant epitopes of La to human cells undergoing spontaneous apoptosis, in a murine xenograft model in vivo and in cultured human fetal cardiocytes rendered apoptotic in vitro, respectively. Anti-La antibodies bound to immunodominant epitopes of La within the NH(2)-terminus and the RNA recognition motif (RRM) region of apoptotic human cells, in both xenografts and fetal cardiocytes. In contrast, human antibodies affinity purified against the COOH-terminal La epitope did not bind apoptotic cells in either model. This defines the topology of redistributed La during apoptosis, with surface exposure of the NH(2)-terminus and RRM regions. The potential importance of anti-La NH(2)-terminal and anti-La RRM specificity was confirmed by detection of this reactivity in mothers of children with congenital heart block. These findings provide insight into both the molecular modification of the La autoantigen during apoptosis and the specificity of antibodies capable of binding to surface-exposed La. Subsequent formation of surface immune complexes may lead to tissue injury in patients with autoimmune diseases such as congenital heart block.