Influence of lumbar intervertebral disc degeneration on the outcome of total lumbar disc replacement: a prospective clinical, histological, X-ray and MRI investigation.

INTRODUCTION: The role of fusion of lumbar motion segments for the treatment of axial low back pain (LBP) from lumbar degenerative disc disease (DDD) without any true deformities or instabilities remains controversially debated. In an attempt to avoid previously published and fusion-related negative side effects, motion preserving technologies such as total lumbar disc replacement (TDR) have been introduced. The adequate extent of preoperative DDD for TDR remains unknown, the number of previously published studies is scarce and the limited data available reveal contradictory results. The goal of this current analysis was to perform a prospective histological, X-ray and MRI investigation of the index-segment's degree of DDD and to correlate these data with each patient's pre- and postoperative clinical outcome parameters from an ongoing prospective clinical trial with ProDisc II (Synthes, Paoli, U.S.A.). MATERIALS AND METHODS: Nucleus pulposus (NP) and annulus fibrosus (AF) changes were evaluated according to a previously validated quantitative histological degeneration score (HDS). X-ray evaluation included assessment of the mean, anterior and posterior disc space height (DSH). MRI investigation of DDD was performed on a 5-scale grading system. The prospective clinical outcome assessment included visual analogue scale (VAS), Oswestry Disability Index (ODI) scores as well as the patient's subjective satisfaction rates. RESULTS: Data from 51 patients with an average follow-up of 50.5 months (range 6.1-91.9 months) were included in the study. Postoperative VAS and ODI scores improved significantly in comparison to preoperative levels (p < 0.002). A significant correlation and interdependence was established between various parameters of DDD preoperatively (p < 0.05). Degenerative changes of NP tissue samples were significantly more pronounced in comparison to those of AF material (p < 0.001) with no significant correlation between each other (p > 0.05). Preoperatively, the extent of DDD was not significantly correlated with the patient's symptomatology (p > 0.05). No negative influence was associated with increasing stages of DDD on the postoperative clinical outcome parameters following TDR (p > 0.05). Increasing stages of DDD in terms of lower DSH scores were not associated with inferior clinical results as outlined by postoperative VAS or ODI scores or the patient's subjective outcome evaluation at the last FU examination (p > 0.05). Conversely, some potential positive effects on the postoperative outcome were observed in patients with advanced stages of preoperative DDD. Patients with more severe preoperative HDS scores of NP samples demonstrated significantly lower VAS scores during the early postoperative course (p = 0.02). CONCLUSION: Increasing stages of DDD did not negatively impact on the outcome following TDR in a highly selected patient population. In particular, no preoperative DDD threshold value was identified from which an inferior postoperative outcome could have been deduced. Conversely, some positive effects on the postoperative outcome were detected in patients with advanced stages of DDD. Combined advantageous effects of progressive morphological structural rigidity of the index segment and restabilizing effects from larger distraction in degenerated segments may compensate for increasing axial rotational instability, one of TDR's perceived disadvantages. Our data reveal a "therapeutic window" for TDR in a cohort of patients with various stages of DDD as long as preoperative facet joint complaints or degenerative facet arthropathies can be excluded and stringent preoperative decision making criteria are adhered to. Previously published absolute DSH values as contraindication against TDR should be reconsidered.

Carcinoma ex pleomorphic adenoma with special reference to the prognostic significance of histological progression: a clinicopathological investigation of 41 cases.

AIMS: To investigate a large series of cases of carcinoma ex pleomorphic adenoma (CEPA) to determine prognostic factors. METHODS AND RESULTS: Thirty cases of CEPA associated with primary pleomorphic adenoma (PA) and 11 cases of CEPA associated with recurrent PA were investigated. The median follow-up was 57.7 months, and ranged from 4 to 156 months. Purely intraductal carcinoma was found in 15 cases. Intraductal and extraductal intracapsular carcinoma together was found in one case. Extracapsular carcinoma was found in 25 cases. Prognosis was good for CEPA that was purely intraductal, extraductal intracapsular, or up to 5 mm extracapsular, and poor for CEPA that was 8 mm or more extracapsular. There were relatively more cases of CEPA with extracapsular invasion of 8 mm or more from recurrent PA than from primary PA, and the prognosis for CEPA associated with recurrent PA was worse than that for CEPA associated with primary PA. CONCLUSIONS: The threshold for distinguishing minor extracapsular invasion with good prognosis from wide extracapsular invasion with poor prognosis is 5 mm. The worse prognosis for CEPA associated with recurrent PA indicates the necessity for close surveillance of patients with recurrent PA.

Immunohistochemical identification of notochordal markers in cells in the aging human lumbar intervertebral disc.

The fate of notochord cells during disc development and aging is still a subject of debate. Cells with the typical notochordal morphology disappear from the disc within the first decade of life. However, the pure morphologic differentiation of notochordal from non-notochordal disc cells can be difficult, prompting the use of cellular markers. Previous reports on these notochordal cell markers only explored the occurrence in young age groups without considering changes during disc degeneration. The aim of this study, therefore, was to investigate presence, localization, and abundance of cells expressing notochordal cell markers in human lumbar discs during disc development and degeneration. Based on pilot studies, cytokeratins CK-8, -18 and -19 as well as Galectin-3 were chosen from a broad panel of potential notochordal cell markers and used for immunohistochemical staining of 30 human lumbar autopsy samples (0-86 years) and 38 human surgical disc samples (26-69 years). In the autopsy group, 80% of fetal to adolescent discs (0-17 years) and 100% of young adult discs (18-30 years) contained many cells with positive labeling. These cells were strongly clustered and nearly exclusively located in areas with granular changes (or other matrix defects), showing predominantly a chondrocytic morphology as well as (in a much lesser extent) a fibrocytic phenotype. In mature discs (31-60 years) and elderly discs (≥ 60 years) only 25 and 22-33%, respectively, contained few stained nuclear cells, mostly associated with matrix defects. In the surgical group, only 16% of samples from young adults (≤ 47 years) exhibited positively labeled cells whereas mature to old surgical discs (>47 years) contained no labeled cells. This is the first study describing the presence and temporo-spatial localization of cells expressing notochordal cell markers in human lumbar intervertebral discs of all ages and variable degree of disc degeneration. Our findings indicate that cells with a (immunohistochemically) notochord-like phenotype are present in a considerable fraction of adult lumbar intervertebral discs. The presence of these cells is associated with distinct features of (early) age-related disc degeneration, particularly with granular matrix changes.

First report of a solid variant of aneurysmal bone cyst in the os sacrum.

We report on a 19-year-old woman with a rapidly growing, solid variant of aneurysmal bone cyst (solid ABC) in the right part of the lateral mass of the sacrum. On admission, the magnetic resonance imaging (MRI) scan disclosed an inhomogeneous low intensity mass right of the centre of the os sacrum with a diameter of 38 x 64 mm and a height of 56 mm on T1 and T2 weighted images. The mass showed homogenous high signal intensity on Gd-enhanced images. Computed tomography demonstrated an expansile osteolytic lesion and (99m)Tc-methylene diphosphonate bone scintigraphy revealed uniform accumulation in the lesion. The histological evaluation showed a proliferation of fibroblasts, histiocytes, chronic inflammatory cells and numerous multinucleated giant cells. Nevertheless, the cells were devoid of nuclear atypia. A cystic component was not observed. In spite of thorough curettage, the patient suffered from recurrence and severe neurological deficits. A review of the literature revealed no previous cases of solid ABC in the sacrum.

Matrix metalloproteinase expression levels suggest distinct enzyme roles during lumbar disc herniation and degeneration.

The disruption of the extracellular disc matrix is a major hallmark of disc degeneration. This has previously been shown to be associated with an up-regulation of major matrix metalloproteinase (MMP) expression and activity. However, until now hardly any data are available for MMP/TIMP regulation and thereby no concept exists as to which MMP/TIMP plays a major role in disc degeneration. The objective of this study was, therefore, to identify and quantify the putative up-regulation of MMPs/TIMPs on the mRNA and protein level and their activity in disc material in relation to clinical data and histological evidence for disc degeneration. A quantitative molecular analysis of the mRNA expression levels for the MMPs (MMPs-1, -2, -3, -7, -8, -9, -13) and the MMP inhibitors (TIMPs-1 and -2) was performed on 37 disc specimens obtained from symptomatic disc herniation or degeneration. In addition, disc specimens from patients without disc degeneration/herniation (=controls) were analyzed. Expression of MMPs-1, -2, -3, -7, -8, -9, -13 and TIMPs-1, -2 was analyzed using quantitative RT-PCR, normalized to the expression level of a house keeping gene (GAPDH). Gene expression patterns were correlated with MMP activity (in situ zymography), protein expression patterns (immunohistochemistry), degeneration score (routine histology) and clinical data. MMP-3 mRNA levels were consistently and substantially up-regulated in samples with histological evidence for disc degeneration. A similar but less pronounced up-regulation was observed for MMP-8. This up-regulation was paralleled by the expression of TIMP-1 and to a lesser extent TIMP-2. In general, these findings could be confirmed with regard to protein expression and enzyme activity. This study provides data on the gene and protein level, which highlights the key role of MMP-3 in the degenerative cascade leading to symptomatic disc degeneration and herniation. Control of the proteolytic activity of MMP-3 may, therefore, come into the focus when aiming to develop new treatment options for early disc degeneration.

Expression of indoleamine 2,3-dioxygenase in tumor endothelial cells correlates with long-term survival of patients with renal cell carcinoma.

PURPOSE: The inflammatory enzyme indoleamine 2,3-dioxygenase (IDO) participates in immune tolerance and tumor immune escape processes by degradation of the essential amino acid tryptophan and formation of toxic catabolites. Here, we analyzed the role of IDO in tumor growth and disease progression in patients with clear cell renal cell carcinoma (RCC). EXPERIMENTAL DESIGN: Expression of IDO mRNA was analyzed by quantitative reverse transcription-PCR in 55 primary and 52 metastatic RCC, along with 32 normal kidneys. Western blot and immunohistochemistry analyses were used to semiquantitatively determine IDO proteins in a subset of tumor samples, in RCC cell lines, and microvessel endothelial cells. IDO expression was correlated with expression of the proliferation marker Ki67 in tumor cells and survival of patients with tumor. RESULTS: More than 75% of the clear cell RCC in comparison to normal kidney contained elevated levels of IDO mRNA, which correlated with their IDO protein content. Low IDO mRNA levels in primary tumors represented an unfavorable independent prognostic factor (hazard ratio, 3.8; P = 0.016). Unexpectedly, immunohistochemical analyses revealed that IDO is nearly exclusively expressed in endothelial cells of newly formed blood vessels and is virtually absent from tumor cells, although RCC cells could principally synthesize IDO as shown by in vitro stimulation with IFN-gamma. A highly significant inverse correlation between the density of IDO-positive microvessels and the content of proliferating Ki67-positive tumor cells in primary and metastatic clear cell RCC was found (P = 0.004). CONCLUSIONS: IDO in endothelial cells might limit the influx of tryptophan from the blood to the tumor or generate tumor-toxic metabolites, thus restricting tumor growth and contributing to survival.

Analysis of tissue distribution of TNF-alpha, TNF-alpha-receptors, and the activating TNF-alpha-converting enzyme suggests activation of the TNF-alpha system in the aging intervertebral disc.

We immunohistochemically analyzed the expression and localization of TNF-alpha, its receptors TNF-RI and -RII, and the TNF-alpha-activating enzyme TACE in human autopsy (n=63) and surgical (n=35) lumbar intervertebral disc samples. In parallel, the TNF-alpha-mRNA was quantified by reverse transcriptase-polymerase chain reaction (RT-PCR). All samples were morphometrically evaluated for the proportion of positively labeled cells in the different anatomical regions of the disc. We detected a significant and comparable expression of all four parameters beginning in young adult age (c. 18 years) and being most extensive in the nucleus pulposus. This level was slightly reduced in older age discs. The annulus fibrosus contained significantly less labeled cells. In accord, the number of TNF-alpha-transcripts was elevated in most cases with immunohistochemical TNF-alpha expression. We provide clear evidence that TNF-alpha is expressed in discs of increasing age, which correlates with histomorphological signs of disc degeneration. In consequence, TNF-alpha seems to be activated (by the converting enzyme TACE) and biologically active through its receptors in human lumbar disc tissue.

Preinvasive intraductal neoplasia in salivary adenocarcinoma, not otherwise specified.

Preinvasive intraductal neoplasia of the salivary glands has only been identified in the rare salivary-duct carcinoma, whereas, it is an established feature of carcinomas of other glands. A fortuitous observation of what appeared to be intraductal tumor in a salivary adenocarcinoma, not otherwise specified, led to the present investigation to determine whether intraductal neoplasia is a significant feature of this carcinoma. Intraductal tumor confined by normal CK14-positive, actin-negative ductal basal cells was identified in 15 of 22 cases (68%). The degree of cellular atypia and the pattern of growth of intraductal tumor was similar to that of the invasive tumor. Cases with intraductal tumor devoid of invasive tumor were not found. Intraductal tumor is identified as the pre-invasive precursor of adenocarcinoma, not otherwise specified, and apparently develops in excretory ducts. The findings support the possibility that different salivary tumors arise from different types of parenchymal cell. Possibly intraductal neoplasia is a universal feature of many types of salivary tumor, but has been overlooked because of the need to use immunohistology to demonstrate it and because it may no longer be present as such when the tumor presents as a clinical lesion.

Posterior lumbar interbody fusion (PLIF) with cages and local bone graft in the treatment of spinal stenosis.

Posterior lumbar interbody fusion (PLIF) implants are increasingly being used for 360 degrees fusion after decompression of lumbar spinal stenosis combined with degenerative instability. Both titanium and PEEK (PolyEtherEtherKetone) implants are commonly used. Assessing the clinical and radiological results as well as typical complications, such as migration of the cages, is important. In addition, questions such as which radiological parameters can be used to assess successful fusion, and whether the exclusive use of local bone graft is sufficient, are frequently debated. We prospectively evaluated 30 patients after PLIF instrumentation for degenerative lumbar spinal canal stenosis, over a course of 42 months. In all cases, titanium cages and local bone graft were used for spondylodesis. The follow-up protocol of these 30 cases included standardised clinical and radiological evaluation at 3, 6, 12 and 42 months after surgery. Overall satisfactory results were achieved. With one exception, a stable result was achieved with restoration of the intervertebral space in the anterior column. After 42 months of follow-up in most cases, a radiologically visible loss of disc space height can be demonstrated. Clinically relevant migration of the cage in the dorsal direction was detected in one case. Based on our experience, posterior lumbar interbody fusion (PLIF) can be recommended for the treatment of monosegmental and bisegmental spinal stenosis, with or without segmental instability. Postoperative evaluation is mainly based on clinical parameters since the titanium implant affects the diagnostic value of imaging studies and is responsible for artefacts. The results observed in our group of patients suggest that local autologous bone graft procured from the posterior elements after decompression is an adequate material for bone grafting in this procedure.

Nonsebaceous lymphadenoma of salivary glands: proposed development from intraparotid lymph nodes and risk of misdiagnosis.

Nonsebaceous lymphadenoma (NSLA) is a rare benign salivary gland tumor composed of lymphoid and epithelial components. By definition, the epithelial component lacks sebaceous differentiation and instead displays a wide range of histological differentiation. In this study, we have collected nine cases of NSLA to characterize their histological and immunohistochemical profiles. The samples were histologically reviewed and immunohistochemical stains for CK5/6, CK7, CK14, CK18, p63, and Ki67 performed. Patients were six males and three females (mean age, 50 years). All tumors were located in the parotid gland and showed intimate intermingling of lymphoid tissue with islands or strands of epithelium with a wide spectrum of histological differentiation. The immunohistochemical profiles mirrored the epithelial differentiation; hence, areas with basaloid or lymphoepithelial differentiation strongly expressed CK5/6, CK14, and p63, while areas with ductal differentiation showed strong positivity for CK18/CK7 and CK5/6/CK14/p63 in luminal and basal cell layers, respectively. A hilus structure with salivary inclusions or D2-40 (podoplanin)-positive marginal sinus was identifiable in four and nine of the cases, respectively, supporting origin within intra-/periparotid lymph nodes. Six cases were initially misdiagnosed as other benign (n = 4) or malignant tumors (n = 2). Our study on the second largest series of NSLA reported to date provides strong evidence that NSLA belongs to the group of salivary gland tumors that pathogenetically develop from embryonic salivary gland inclusions in intra-/periparotid lymph nodes. Knowledge of the wide histological spectrum of this rare and presumably underreported tumor is important in order to avoid misdiagnosis, particularly as malignant tumor.

Acute liver failure, rupture and hemorrhagic shock as primary manifestation of advanced metastatic disease.

BACKGROUND: Malignancies rarely cause of acute liver failure, the presence of which have to be ruled-out during transplant evaluation. Tumor-related liver ruptures sporadically occur and might further complicate patient management. CASE REPORT: We report the case of a previously healthy 56-year-old male with complaints of abdominal pain. Initially, levels of liver enzymes were elevated, however, comprehensive imaging examinations revealed no gross abnormalities. As acute liver failure developed, transplantation was evaluated. Sudden liver rupture and hemorrhage forced the performance of an emergency laparotomy. Hepatectomy was planned, until a donor organ was allocated. Intraoperatively, the liver unexpectedly revealed diffuse tumor infiltration. Without further therapeutical options, the patient died. Immunohistochemistry showed metastatic infiltration of a carcinoma of unknown primary. CONCLUSION: Even in previously healthy patients suffering from acute liver failure, exclusion of malignancies is mandatory before transplantation. As imaging might be misleading, a biopsy should be considered early in unresolved cases.

Histological analysis of surgical lumbar intervertebral disc tissue provides evidence for an association between disc degeneration and increased body mass index.

BACKGROUND: Although histopathological grading systems for disc degeneration are frequently used in research, they are not yet integrated into daily care routine pathology of surgical samples. Therefore, data on histopathological changes in surgically excised disc material and their correlation to clinical parameters such as age, gender or body mass index (BMI) is limited to date. The current study was designed to correlate major physico-clinical parameters from a population of orthopaedic spine center patients (gender, age and BMI) with a quantitative histologic degeneration score (HDS). METHODS: Excised lumbar disc material from 854 patients (529 men/325 women/mean age 56 (15-96) yrs.) was graded based on a previously validated histologic degeneration score (HDS) in a cohort of surgical disc samples that had been obtained for the treatment of either disc herniation or discogenic back pain. Cases with obvious inflammation, tumor formation or congenital disc pathology were excluded. The degree of histological changes was correlated with sex, age and BMI. RESULTS: The HDS (0-15 points) showed significantly higher values in the nucleus pulposus (NP) than in the annulus fibrosus (AF) (Mean: NP 11.45/AF 7.87), with a significantly higher frequency of histomorphological alterations in men in comparison to women. Furthermore, the HDS revealed a positive significant correlation between the BMI and the extent of histological changes. No statistical age relation of the degenerative lesions was seen. CONCLUSIONS: This study demonstrated that histological disc alterations in surgical specimens can be graded in a reliable manner based on a quantitative histologic degeneration score (HDS). Increased BMI was identified as a positive risk factor for the development of symptomatic, clinically significant disc degeneration.

Pathogenesis of sialadenosis: possible role of functionally deficient myoepithelial cells.

OBJECTIVES: The pathogenesis of acinar enlargement in sialadenosis is obscure. As myoepithelial cells had been reported to show degenerative changes, we decided to investigate the possible role of functionally deficient myoepithelial cells in the development of sialadenosis. STUDY DESIGN: This study was a morphometric analysis of glands immunohistochemically stained for CK14, alpha-actin, and Ki67 in 10 cases of sialadenosis and 11 normal parotids. RESULTS: In sialadenosis, acini were much larger; there was a minor decrease in the density of the distribution of myoepithelial cells stained for CK14 and a major decrease in the density of the distribution and thickness of the myofilament component of myoepithelial cells stained for alpha-actin; and the proliferation of acinar and myoepithelial cells was reduced. CONCLUSIONS: Our results demonstrate a major loss and thinning of the myofilament component of the myoepithelial cells and thereby a loss of mechanical support for the acini in sialadenosis. This possibly allows acinar cells to expand as secretory granules accumulate intracellularly to produce the great acinar enlargement. This functional myoepithelial insufficiency is possibly a consequence of an autonomic neuropathy secondary to severe metabolic or hormonal disorders.

Obligate basal cell component in salivary oncocytoma facilitates distinction from acinic cell carcinoma.

The differential diagnosis between benign salivary oncocytoma (ONC) and low-grade malignant acinic cell carcinoma (ACC) can be difficult due to a significant histomorphological overlap of the structural and cytological presentation of both tumor types. To the best of our knowledge a comprehensive study comparing (immuno-)histological markers in cases of difficult differential diagnosis between ONC and ACC has not yet been performed. We investigated a panel of different immunohistochemical (CK5/6, CK14, CK7, CK18, p63 and Ki67) and histochemical (PAS, alpha-amylase) markers in 12 cases of ONC and 19 cases of ACC. The statistically significant stronger expression of CK7 in ONC and stronger expression of PAS and alpha-amylase in ACC in routine practice each is hampered by a pronounced overlap between both tumor groups. The obligate presence of an additional small basal cell component in all cases of ONC, demonstrable with p63 and CK5/6, enables a straightforward distinction from ACC, being constantly devoid of a basal cell component. Unexpectedly, CK14 is not a suitable marker for a reliable proof of these basal cells. The detection of this basal cell component in ONC in routine Hematoxylin-eosin stain is difficult and in some cases not possible; therefore, immunohistochemistry with p63 or CK5/6 is recommended for selected cases.

Expression and distribution of tumor necrosis factor alpha in human lumbar intervertebral discs: a study in surgical specimen and autopsy controls.

STUDY DESIGN: Immunohistochemical study of tumor necrosis factor alpha expression in autopsy and surgical specimens of human lumbar intervertebral discs. OBJECTIVES: To investigate the occurrence and localization of tumor necrosis factor alpha in intervertebral disc tissue and to correlate its expression with age and the degree of disc degeneration. SUMMARY OF BACKGROUND DATA: The source and origin of discogenic pain are as yet unknown. Recently identified changes of the cellular phenotype during senescence and disc pathology with partly phagocytic properties suggest an 'inflammatory' phenotype. Tumor necrosis factor alpha is one of the most potent proinflammatory cytokines possibly modulating cellular phenotypes. It may also promote pain induction. Very little is known about the occurrence and localization of tumor necrosis factor alpha in intervertebral disc tissue of defined age and degree of histologic tissue degeneration. METHODS: The study population comprised 20 cross-sections of the complete motion segment of human lumbar vertebrae (age range 0-86 years) obtained at autopsy and 28 surgical disc specimens of individuals undergoing lumbar surgical interventions for various reasons. The temporospatial distribution of tumor necrosis factor alpha-positive cells using a polyclonal antibody was correlated with a histologic degeneration score. RESULTS: Tumor necrosis factor alpha is expressed substantially in (nonsymptomatic) autopsy material in fetal/infantile and older adult nucleus pulposus, whereas it is sparsely expressed in adolescent and young adult nucleus pulposus. In the anulus fibrosus, tumor necrosis factor alpha is not found in young adults (<25 years), but then significantly increases in extent. In contrast, symptomatic nucleus pulposus and anulus fibrosus (surgical material) contain substantially more tumor necrosis factor alpha-positive cells. A significant positive correlation of tumor necrosis factor alpha expression and disc degeneration (histologic degeneration score) was found for the anulus fibrosus in both sample groups. In the surgical material, an additional significant positive correlation was identified for nuclear tumor necrosis factor alpha, disc degeneration, and age. CONCLUSIONS: Tumor necrosis factor alpha is substantially expressed in disc material of symptomatic patients (surgical specimens) in comparison to samples taken at autopsy. The expression of tumor necrosis factor alpha in early fetal/infantile nucleus pulposus may indicate 'physiologic' tissue disarrangement with closure of the blood vessel canals. The expression of tumor necrosis factor alpha in adult discs, in contrast, is statistically associated with disc degeneration. Its occurrence in adults of more advanced age suggests that tumor necrosis factor alpha is not involved in the initiation of disc degeneration, but may be associated with further promotion of degenerative disarrangement and pain induction.

Cell density-dependent regulation of matrix metalloproteinase and TIMP expression in differently tumorigenic breast cancer cell lines.

Matrix metalloproteinases (MMPs) play a key role in cellular invasion and growth. Recent observations on tumor tissue samples suggest that MMP activity is altered in relation to cell density. Therefore, we examined MMP(-1,-2,-3,-8,-9,-10,-11 and -13) and TIMP-1/-2 expression of well-defined cell densities in breast carcinoma cell lines with differing in vivo tumorigenicity/invasiveness (MCF-7 < MDA-MB-468 < MDA-MB-231 < MDA-MB-435). Chemoinvasion assays were performed to link the in vitro data to the in vivo behavior. In accord with previous in vivo data, expression levels of most MMPs decreased significantly with increasing cell density and correlated well with a lower in vitro invasiveness of confluent cells. Since these data suggested that cell density regulates transcription and the promoter regions of most MMPs have AP-1 transcription factor binding consensus sequences, we tested whether functional AP-1 protein was involved in the mechanism of MMP downregulation by cell density. A role for AP-1 was confirmed by over-expression of c-Jun and c-fos in confluent MDA-MB-231 cells, showing with c-Jun increased MMP-2 (5-fold), MMP-3 (1.6-fold), and MMP-9 (160-fold) expression, as well as enhanced invasive potential, while TIMP-1 expression was down-regulated (2-fold) when compared to vector controls. Our data provide clear evidence that cell density regulates major MMPs and TIMPs which are controlled by AP-1 activity so that ultimately a major regulation pathway for the control of the invasive potential of tumor cells is presented.

Classification of age-related changes in lumbar intervertebral discs: 2002 Volvo Award in basic science.

STUDY DESIGN: A histologic study on age-related changes of the human lumbar intervertebral disc was conducted. OBJECTIVES: To investigate comprehensively age-related temporospatial histologic changes in human lumbar intervertebral disc, and to develop a practicable and reliable classification system for age-related histologic disc alteration. SUMMARY OF THE BACKGROUND DATA: No comprehensive microscopic analysis of age-related disc changes is available. There is no conceptual morphologic framework for classifying age-related disc changes as a reference basis for more sophisticated molecular biologic analyses of the causative factors of disc aging or premature aging (degeneration). METHODS: A total of 180 complete sagittal lumbar motion segment slices obtained from 44 deceased individuals (fetal to 88 years of age) were analyzed with regard to 11 histologic variables for the intervertebral disc and endplate, respectively. In addition, 30 surgical specimens (3 regions each) were investigated with regard to five histologic variables. Based on the semiquantitative analyses of 20,250 histologic variable assessments, a classification system was developed and tested in terms of validity, practicability, and reliability. The classification system was applied to cadaveric and surgical disc specimens not included in the development of the classification system, and the scores were assessed by two additional independent raters. RESULTS: A semiquantitative analyses provided clear histologic evidence for the detrimental effect of a diminished blood supply on the endplate, resulting in the tissue breakdown beginning in the nucleus pulposus and starting in the second life decade. Significant temporospatial variations in the presence and abundance of histologic disc alterations were observed across levels, regions, macroscopic degeneration grades, and age groups. A practicable classification system for age-related histologic disc alterations was developed, resulting in moderate to excellent reliability (kappa values, 0.49-0.98) depending on the histologic variable. Application of the classification system to cadaveric and surgical specimens demonstrated a significant correlation with age ( < 0.0001) and macroscopic grade of degeneration ( < 0001). However, substantial data scatter caution against reliance on traditional macroscopic disc grading and favor a histology-based classification system as a reference standard. CONCLUSIONS: Histologic disc alterations can reliably be graded based on the proposed classification system providing a morphologic framework for more sophisticated molecular biologic analyses of factors leading to age-related disc changes. Diminished blood supply to the intervertebral disc in the first half of the second life decade appears to initiate tissue breakdown.

Immunolocalization of phagocytic cells in normal and degenerated intervertebral discs.

STUDY DESIGN: An immunohistochemical study on human autopsy lumbar intervertebral discs and surgical specimens was conducted. OBJECTIVE: To investigate the presence of phagocytic cells within herniated and nonherniated disc tissue and its correlation with disc calcification and degeneration. SUMMARY OF BACKGROUND DATA: Increasing knowledge is gathered on the molecular mechanisms of extracellular matrix degradation during the process of disc degeneration. However, the data available on the cells involved in this process are sparse. METHODS: Three different study populations were investigated: 1) 31 midsagittal tissue slices (age range, 0-86 years) encompassing the complete motion segment were decalcified and stained with a monoclonal antibody against the lysosomal CD68 antigen; 2) 12 additional midsagittal (undecalcified) tissue slices from normal fresh cadavers were resin-embedded and used for colocalization of calcifications (Kossa staining) and CD68-positive cells; and 3) in 53 surgical disc specimens from 32 individuals undergoing lumbar surgical interventions, the abundance of CD68-positive cells was correlated with diagnostic groups and magnetic resonance image findings. RESULTS: In the discs of fetuses, infants, and adolescents, no labeled cells were seen. However, CD68-positive cells were detected in the nucleus pulposus of all individuals with histomorphologic signs of disc degeneration, predominantly in discs adjacent to cleft formations. Morphologically, CD68-positive cells did not differ from nuclear chondrocytes. In the anulus fibrosus, CD68-positive cells were seen less frequently. In the resin-embedded specimens, CD68-positive cells were not associated with tissue calcifications. In most of the surgical specimens, positive cells in cluster-like arrangements were seen frequently, particularly in areas of vascular ingrowth. CONCLUSIONS: This is the first study describing the abundant presence of CD68-positive cells in human nonherniated disc nucleus pulposus. The findings additionally suggests that these cells are not invaded monocytes or macrophages, but rather, transformed resident cells. It is assumed that these cells are involved in the phagocytosis of extracellular matrix, and that discal cells therefore promote disc degradation, ultimately leading to a loss of biomechanical properties.

The tumour suppressor gene CEACAM1 is completely but reversibly downregulated in renal cell carcinoma.

CEACAM1 acts as a tumour suppressor in various epithelial tumours. On the other hand, de novo expression of CEACAM1 is strongly associated with reduced disease-free survival of melanoma and non-small cell lung carcinoma patients. Since effector functions of natural killer and T cells are inhibited by homophilic CEACAM1 interaction, immune escape could be responsible for the poor prognosis of these patients. Here, we describe CEACAM1 expression in normal kidney, renal adenomas and renal cell carcinomas (RCC) using a novel antibody generated by genetic immunization. In normal kidney, CEACAM1 was found in epithelial cells of proximal tubules and in endothelial cells. In contrast, tumour cells of 30 clear cell, three chromophobic, and two chromophilic RCCs were completely devoid of CEACAM1. Renal adenomas also lacked CEACAM1 expression. Similarly, RCC cell lines CaKi1, CaKi2, A498, and RCC26 exhibited no or low-level CEACAM1 expression. However, CEACAM1 expression was transiently induced in A498 cells upon contact with allogeneic CD8+ T cells, mediated at least in part by interferon-gamma. Furthermore, the majority of tumour-infiltrating T and NK cells expressed CEACAM1 upon stimulation. Thus, transient expression of the tumour suppressor CEACAM1 by tumour cells and subsequent homophilic interaction with CEACAM1 on tumour-infiltrating lymphocytes could represent a novel immune escape mechanism in RCC.

Dose-related effects of extracorporeal shock waves on rabbit quadriceps tendon integrity.

BACKGROUND: Recently, morphological signs of damage were reported in rabbit Achilles tendon following extracorporeal shock wave application (ESWA) with an energy flux density (EFD) of 0.6 mJ/mm(2). However, it is unknown whether or not the same can be found after ESWA to other tendons such as the quadriceps tendon. METHODS: We investigated the effects of ESWA in vivo on rabbit quadriceps tendon. Animals received 1,500 SW pulses each of different EFD ranging between 0.0 and 1.2 mJ/mm(2) on either the left or right quadriceps tendon. ESWA effects were investigated by histopathological examination. RESULTS: ESWA with EFD of 0.5 mJ/mm(2) upwards resulted in edema within the paratenon. ESWA with EFD of 1.2 mJ/mm(2) resulted in various morphological signs of damage within the tendon and paratenon. CONCLUSIONS: We conclude that ESWA to the quadriceps tendon in clinical experimental use should be restricted to EFD less than 0.5 mJ/mm(2).