Long-term functional success and patient-reported outcomes after female one-stage buccal mucosal graft urethroplasty.

INTRODUCTION AND OBJECTIVES: Female urethral strictures are a rare condition that significantly impacts patients' quality of life. Patient-reported outcomes are crucial, yet data regarding sexual function and treatment satisfaction are scarce. We aimed to provide insights from a reconstructive referral center. PATIENTS AND METHODS: We conducted a retrospective analysis of women treated with ventral onlay one-stage buccal mucosa graft urethroplasty for urethral strictures between 2009-2023. We assessed objective (retreatment-free survival, ΔQmax) and subjective outcomes (validated patient-reported outcomes). RESULTS: Of 12 women, 83% and 17% had iatrogenic and idiopathic strictures, respectively. Median number of prior interventions was 6. Strictures were located meatal and mid-urethral in 25% and 75%, respectively, 22% had the bladder neck involved. Median graft length was 2 cm. At median follow-up of 66 months, 33% of patients underwent stricture retreatment, but only one case occurred within the first 2 years postoperatively. The median improvement in maximum flow rate (ΔQmax) was 10 ml/s. Median International Consultation on Incontinence Questionnaire Female Lower Urinary Tract Symptoms Modules (ICIQ-FLUTS) scores were 8 for filling symptoms, 6 for voiding symptoms, and 3 for incontinence symptoms. Median ICIQ-FLUTSsex score was 4. Higher scores indicate a higher symptom burden. Median ICIQ-Satisfaction outcome and satisfaction scores were 18 and 7, respectively, reflecting high treatment satisfaction. CONCLUSIONS: Buccal mucosal graft urethroplasty by ventral onlay for female urethral strictures yields effective, durable, and positively received outcomes. However, larger studies across multiple institutions are necessary to further assess its efficacy, especially regarding patient-reported experiences and sexual function.

[Update on ureteral reconstruction 2024]. / Update Harnleiterrekonstruktion 2024.

Ureteral strictures can occur along the entire course of the ureter and have many different causes. Factors involved in the development include, among other things, congenital anomalies, iatrogenic injuries during endoscopic as well as open or minimally invasive visceral surgical, gynecological, and urological procedures as well as prior radiation therapy. Planning treatment for ureteral strictures requires a detailed assessment of stricture and patient characteristics. Given the various options for ureteral reconstruction, various methods must be considered for each patient. Short-segment proximal strictures and strictures at the pyeloureteral junction are typically surgically managed with Anderson-Hynes pyeloplasty. End-to-end anastomosis can be performed for short-segment proximal and middle ureteral strictures. Distal strictures are treated with ureteroneocystostomy and are often combined with a Boari and/or Psoas Hitch flap. Particularly, the treatment of long-segment strictures in the proximal and middle ureter remain a surgical challenge. The use of bowel interposition is an established treatment option for this, offering good functional results but also potential associated complications. Robot-assisted surgery is increasingly becoming a minimally invasive treatment alternative to reduce hospital stays and optimize postoperative recovery. However, open surgical ureteral reconstruction remains an established procedure, especially after multiple previous abdominal operations.

Outcome groups and a practical tool to predict success of shock wave lithotripsy in daily clinical routine.

PURPOSE: To improve outcome prediction of extracorporeal shock wave lithotripsy (SWL) by development of a model based on easily available clinical and radiographical predictors and suitable for daily clinical use. MATERIALS AND METHODS: We evaluated predictive factors for SWL success in 517 consecutive patients suffering from urinary calculi who underwent SWL between 2010 and 2018. Analyses included descriptive statistics, receiver operating characteristic statistics and logistic regression. Predictive value was improved by combining parameters using model selection and recursive partitioning. RESULTS: Of the 517 patients, 310 (60.0%) had a successful SWL. Best individual predictor of SWL success was mean attenuation (MAV), with an area under the curve (AUC) of 0.668, and an optimal cutpoint (OC) of 987.5 HU. The best multivariable model, including MAV, stone size, skin to stone distance (SSD), presence of an indwelling stent, and four interaction effects, yielded an AUC of 0.736. Recursive partitioning would categorize patients into three outcome groups with high (76.9%), intermediate (41%) and low (10%) success probability. High probability of SWL success (76.9%) was found for patients with a stone with MAV ≤ 987 HU or with MAV > 987 HU but stone size ≤ 11 mm and SSD (45°) ≤ 88 mm. CONCLUSION: A model based on four established predictors, and provided as an Excel®-Tool, can clearly improve prediction of SWL success. In addition, patients can be classified into three defined outcome groups based on simple cutpoint combinations. Both tools improve informed decision-making in daily clinical practice and might reduce failure rates.

Vesico-urethral anastomotic stenosis following radical prostatectomy: a multi-institutional outcome analysis with a focus on endoscopic approach, surgical sequence, and the impact of radiation therapy.

OBJECTIVES: To investigate the predictors of recurrence and of de novo incontinence in patients treated by transurethral incision or resection for vesico-urethral anastomotic stenosis (VUAS) after radical prostatectomy. MATERIAL AND METHODS: All patients undergoing endoscopic treatment for VUAS between March 2009 and October 2016 were identified in our multi-institutional database. Digital chart reviews were performed and patients contacted for follow-up. Recurrence was defined as any need for further instrumentation or surgery, and de-novo-incontinence as patient-reported outcome. RESULTS: Of 103 patients undergoing endoscopic VUAS treatment, 67 (65%) underwent transurethral resection (TR) and 36 (35%) transurethral incision (TI). TI was performed more frequently as primary treatment compared to TR (58% vs. 37%; p = 0.041). Primary and repeated treatment was performed in 46 (45%) and 57 patients (55%), respectively. Overall, 38 patients (37%) had a history of radiation therapy. There was no difference in time to recurrence for primary vs repeat VUAS treatment, previous vs no radiation, TR compared to TI (all p > 0.08). Regarding treatment success, no difference was found for primary vs. repeat VUAS treatment (50% vs. 37%), previous radiation vs. no radiation (42% vs. 43%), and TR vs. TI (37% vs. 53%; all p ≥ 0.1). Postoperative de novo incontinence was more common after TI vs. TR (31% vs. 12%; p = 0.032), no difference was observed for previous radiation therapy vs. no radiation therapy (18% vs. 18%; p > 0.9) or primary vs. repeat VUAS treatment (22% vs. 16%; p = 0.5). CONCLUSION: VUAS recurrence after endoscopic treatment is not predictable. Endoscopic treatment with TI showed a higher risk for de novo incontinence than TR, and previous irradiation and the number of treatments do not influence incontinence.

[Fistula surgery]. / Fistelchirurgie.

Vesicovaginal fistulas are a rare problem in the western world but are frequent occurrences in developing countries. In Germany the most frequent cause is hysterectomy. Vesicovaginal fistulas can be treated by the transvaginal or transabdominal approach depending on the characteristics of the fistula and the patient. The incidence and complexity of urorectal fistulas increase with the number of cumulative sequences of prostate cancer treatment. Overall there is no clear consensus about the optimal surgical approach route. The surgical treatment of both vesicovaginal and urorectal fistulas is associated with high permanent fistula closure rates; however, for both entities if the fistula is discovered early enough, conservative treatment with a temporary catheter drainage can be tried, depending on the underlying cause. For both conditions fistula repair in irradiated patients shows a much lower success rate. A spontaneous closure of fistulas in radiogenic fistulas is also not to be expected.

[What is the perception of the 10-point plan of the German Federal Ministry of Health against multidrug-resistant pathogens and measures of antibiotic stewardship? : An interdisciplinary analysis among German clinicians and development of a decision tool for urologists]. / Wie werden der 10-Punkte-Plan des Deutschen Bundesministeriums für Gesundheit zur Bekämpfung resistenter Erreger und Maßnahmen des Antibiotic Stewardship wahrgenommen? : Eine fachübergreifende Analyse der Kenntnis deutscher Klinikärzte und Entwicklung einer urologischen Handlungsanweisung.

BACKGROUND: Due to increasing antibiotic resistances, relevant treatment problems are currently emerging in clinical practice. In March 2015, the German Federal Ministry of Health (BMG) published a 10-point plan designed to combat this development. Furthermore, the first German guideline on antibiotic stewardship (ABS) was implemented in 2013 and instructs physicians of different specialties about several treatment considerations. Evidence is scarce on how such concepts (10-point plan/BMG, ABS) are perceived among clinicians. MATERIALS AND METHODS: Within the MR2 study (Multiinstitutional Reconnaissance of practice with MultiResistant bacteria - a survey focusing on German hospitals), a questionnaire including 4 + 35 items was sent to 18 German hospitals between August and October 2015, surveying internists, gynecologists, general surgeons, and urologists. Using multivariate logistic regression models (MLRM), the impact of medical specialty and further criteria on the endpoints (1) awareness of the 10-point plan/BMG and (2) knowledge of ABS measures were assessed. Fulfillment of endpoints was predefined when average or full knowledge was reported (reference: poor to no knowledge). RESULTS: Overall response rate was 43% (456/1061) for fully evaluable questionnaires. Only 63.0 and 53.6% of urologists and nonurologists (internists, gynecologists, and general surgeons), respectively, attended training courses regarding multidrug-resistance or antibiotic prescribing in the 12 months prior to the study (P = 0.045). The endpoints average and full knowledge regarding 10-point plan/BMG and ABS measures were fulfilled in only 31.4 and 32.8%, respectively. In MLRM, clinicians with at least one previous training course (reference: no training course) were 2.5- and 3.8-fold more likely to meet respective endpoint criteria (all P < 0.001). Medical specialty (urologists vs. nonurologists) did not significantly impact the endpoints in both MLRM. CONCLUSIONS: The 10-point plan/BMG and ABS programs should be implemented into clinical practice, but awareness and knowledge of both is insufficient. Thus, it stands to reason that the actual realization of such measures is inadequate and continuous training towards rational prescription of antibiotics is necessary, regardless of medical specialty.

Is there evidence for a close connection between side of intravesical tumor location and ipsilateral lymphatic spread in lymph node-positive bladder cancer patients at radical cystectomy? Results of the PROMETRICS 2011 database.

PURPOSE: To evaluate the possible association between bladder tumor location and the laterality of positive lymph nodes (LN) in a prospectively collected multi-institutional radical cystectomy (RC) series. METHODS: The study population included 148 node-positive bladder cancer (BC) patients undergoing RC and pelvic lymph node dissection in 2011 without neoadjuvant chemotherapy and without distant metastasis. Tumor location was classified as right, left or bilateral and compared to the laterality of positive pelvic LN. A logistic regression model was used to identify predictors of ipsilaterality of lymphatic spread. Using multivariate Cox regression analyses (median follow-up: 25 months), the effect of the laterality of positive LN on cancer-specific mortality (CSM) was estimated. RESULTS: Overall, median 18.5 LN [interquartile range (IQR), 11-27] were removed and 3 LN (IQR 1-5) were positive. There was concordance of tumor location and laterality of positive LN in 82% [95% confidence interval (CI), 76-89]. Patients with unilateral tumors (n = 78) harbored exclusively ipsilateral positive LN in 67% (95% CI 56-77). No criteria were found to predict ipsilateral positive LN in patients with unilateral tumors. CSM after 3 years in patients with ipsilateral, contralateral, and bilateral LN metastasis was 41, 67, and 100%, respectively (p = 0.042). However, no significant effect of the laterality of positive pelvic LN on CSM could be confirmed in multivariate analyses. CONCLUSIONS: Our prospective cohort showed a concordance of tumor location and laterality of LN metastasis in BC at RC without any predictive criteria and without any influence on CSM. It is debatable, whether these findings may contribute to a more individualized patient management.

Submicrometer axial resolution optical coherence tomography.

Optical coherence tomography (OCT) with unprecedented submicrometer axial resolution achieved by use of a photonic crystal fiber in combination with a compact sub-10-fs Ti:sapphire laser (Femtolasers Produktions) is demonstrated for what the authors believe is the first time. The emission spectrum ranges from 550 to 950 nm (lambda(c)=725 nm , P(out)=27 mW) , resulting in a free-space axial OCT resolution of ~0.75 mum , corresponding to ~0.5 mum in biological tissue. Submicrometer-resolution OCT is demonstrated in vitro on human colorectal adenocarcinoma cells HT-29. This novel light source has great potential for development of spectroscopic OCT because its spectrum covers the absorption bands of several biological chromophores.

Cryopreparation provides new insight into the effects of brefeldin A on the structure of the HepG2 Golgi apparatus.

High-pressure freezing and freeze-substitution were used to study Golgi ultrastructure and its brefeldin A-induced transformations in HepG2 human hepatoma cells. Cryoimmobilization arrested subcellular dynamics within milliseconds, thus considerably improving the temporal resolution in monitoring the very early effects of high brefeldin concentrations at the ultrastructural level (i.e., 20 microg/ml brefeldin applied for 35 s to 8 min). Moreover, this approach ruled out possible cumulative and/or synergistic effects of the drug and fixatives. Several findings differed from studies based on chemical fixation. In particular, Golgi breakdown did not proceed gradually but occurred in distinct steps. We found a conspicuous lag between the absence of nonclathrin coats on Golgi membranes after 30 s of brefeldin treatment and the disassembly of the stacks, which did not start until after 90 to 120 s. At this time, domains at the trans and cis faces separated from the stacks, starting tubulation and fragmentation. After 3-5 min the Golgi apparatus was completely replaced by loose meshworks of straight tubules of different sizes and staining properties; also frequent were bent tubules and vesicles forming glomerule-like structures. After 8 min all kinds of Golgi-derived structures had aggregated within huge clusters. The morphologically highly distinct structures found after brefeldin treatment could in part be correlated with particular Golgi domains in the control cells.

Evidence for a role of FGF-2 and FGF receptors in the proliferation of non-small cell lung cancer cells.

Basic fibroblast growth factor (FGF-2) has been implicated in the progression of human tumours via both autocrine and paracrine (angiogenic) activities. We investigated the expression of FGF-2 and FGF receptors (FGFR-1 to -4) in NSCLC cell lines (N = 16), NSCLC surgical specimens (N = 21) and 2 control cell lines. Our data show that almost all NSCLC cells produce elevated levels of FGF-2 and FGFR in vitro and in vivo. FGF-2 expression did correlate with a short doubling time as well as with potent anchorage-independent growth of NSCLC cell lines. In contrast with control cells, NSCLC cells did not secrete considerable amounts of FGF-2 into the extracellular space. Expression levels of FGFR-1 and -2 in NSCLC cell lines correlated with FGF-2 production. FGFR were located at the plasma membranes in some low FGF-2-producing NSCLC and control cell lines. These cells were sensitive to the proliferative effect of recombinant FGF-2 (rFGF-2). In NSCLC cell lines with an enhanced FGF-2 production, representing the majority studied, FGFR localisation was predominantly intracellular. These cells were insensitive to both the proliferative effect of rFGF-2 and growth inhibition by FGF-2-neutralising antibodies. In contrast, several agents antagonised FGF-2 intracellularly impaired growth of almost all NSCLC cell lines. Our data suggest a role of FGF-2 and FGFR in the growth stimulation of NSCLC cells possibly via an intracrine mechanism.

Endocytic routes to the Golgi apparatus.

The endocytic routes of labelled lectins as well as cationic ferritin were studied in cells with a regulated secretion, i.e. pancreatic beta cells, and in constitutively secreting cells, i.e. fibroblasts and HepG2 hepatoma cells, paying particular attention to routes into the Golgi apparatus. Considerable amounts of internalised molecules were taken up into the trans Golgi network (TGN) and into Golgi subcompartments in all three cell types as well as in secretory granules of the pancreatic beta cells. The internalised materials did not pass rapidly the TGN and Golgi stacks, but were still present hours after internalisation, being then particularly concentrated in TGN-elements and in the transmost Golgi cisterna. Endocytosed materials reached forming secretory granules present in the TGN. Further, direct fusion between endocytotic vesicles and mature secretory granules was observed. Golgi subcompartments as well as endocytic TGN containing endocytosed materials were in close apposition to specialised regions of the endoplasmic reticulum. The Golgi apparatus including its parts containing endocytosed materials were transformed into a tubular reticulum upon treatment with the fungal metabolite Brefeldin A. Rarely, internalised material was observed in the lumen of the endoplasmic reticulum, thus providing evidence for an endocytic plasma membrane to endoplasmic reticulum route.

Possible role of the multidrug resistance-associated protein (MRP) in chemoresistance of human melanoma cells.

Human malignant melanoma is characterised by unresponsiveness to conventional chemotherapy. Melanoma-derived cell lines are often markedly chemoresistant, suggesting that cellular mechanisms mediate the multidrug resistance (MDR) phenotype. The multidrug resistance-associated protein (MRP) is a drug transporter protein associated with resistance to a broad spectrum of lipophilic drugs. To investigate whether MRP is involved in intrinsic drug resistance of human melanoma, we analysed expression and functional activity of MRP as well as its impact on chemoresistance in 40 melanoma cell lines (35 established by us from primary and metastatic lesions and 5 obtained from international sources), as well as in one dysplastic naevus-derived cell line and in normal melanocytes. By reverse transcriptase-polymerase chain reaction various levels of MRP mRNA were detected in all melanoma cell lines, and by immunoblot the corresponding protein in a high percentage of them. Functional activity of MRP was assayed by analysing cellular accumulation of 3H-daunomycin (3H-DM) and calcein in response to MRP-modulators by beta-spectrometric and fluorescence-activated cell sorter analysis, respectively. Probenecid (PRO), N-ethylmaleimide (NEM) and benzbromarone (BB) moderately (< or = 1.43-fold) but significantly enhanced intracellular accumulation of MRP substrate probes corresponding to MRP expression. Moreover, the sensitivity of melanoma cell lines to daunomycin (DM) and doxorubicin (DOX), but not to vinblastine (VBL), etoposide (VP-16) and cisplatin (CDDP), analysed by an MTT-based survival assay, were inversely correlated with MRP-gene expression. Our results imply that MRP may be a component of the intrinsic chemoresistance phenotype characteristic of human malignant melanoma.

Intrinsic MDR-1 gene and P-glycoprotein expression in human melanoma cell lines.

Metastatic malignant melanoma is considered a chemotherapy-refractory malignancy. A few previous studies have delivered contradictory results regarding the presence and functionality of P-glycoprotein (P-gp), a transmembranous protein associated with the classical multidrug resistance (cMDR), in malignant melanoma. Therefore we have investigated this issue on 33 cell lines established from primary and metastatic lesions of human malignant melanoma, comparing different cMDR detection methods. Immunocytochemically 33% of the cell lines stained positive for P-gp. The data correlated with those of a P-gp-radioimmunometric (antibody-binding) assay. When RT-PCR was used for MDR-1 mRNA determination, 76% of the melanoma cell lines scored positive. Slot-blot analysis was seen to be less sensitive than RT-PCR. Results from the functional P-gp assays, using daunomycin (DM) as MDR-substrate, showed no influence of P-gp expression on drug accumulation and cytotoxicity. However, the cMDR-modifier verapamil (VP) significantly increased both parameters in those melanoma cells with the highest P-gp levels. We conclude that cMDR is apparently not the decisive but probably a complementary protective mechanism against toxic agents in malignant melanoma.

Inhibition of DNA synthesis and oncogene expression in tumor cells by the biological factor DIF.

A regulatory factor isolated from the maternal part of bovine placentas (decidua inhibitory factor, DIF) inhibits the incorporation of thymidine into the DNA of a variety of animal and human tumors. The degree of inhibition is dependent on the concentration of the factor. Results indicate that signal transduction occurs via a Ca2+ mobilizing pathway after specific binding of the inhibitor to tumor cell surface receptors. On of the main consequences of DIF action is the inhibition of c-fos and c-myc expression and/or degradation.

Use of CA 125 monoclonal antibody to monitor patients with ovarian cancer.

The monoclonal antibody (mAb) OC 125 reacts with an antigen on human ovarian carcinoma (OVCA) cells that is also shed into the body fluids and can be detected in patients' sera and/or ascites with a radioimmunometric assay. For the present study, serum CA 125 levels of patients (n = 36) with different stages of OVCA were investigated. Serum levels seem to correlate with tumor burden. In stages I and II (n = 12), 33% of patients were CA 125 positive, whereas 70% of stage III and IV patients (n = 24) were CA 125 positive. Mean serum levels were in 93 U/ml (stages I, II) and 279 U/ml (stages III, IV). CA 125 levels in ascites and in pleural effusions were manyfold higher than serum levels of the same patients (P less than 0.0001). Immunohistochemical investigations of CA 125 in different ovarian tumors (n = 91) revealed that 85% of malignant and 75% of borderline serous cystadenocarcinomas had detectable CA 125 surface expression. Furthermore, 71% of benign tumors showed the CA 125 epitope, whereas mucinous tumors were negative for this marker. One of six ovarian cancer cell lines was CA 125 positive, whereas in 6 of 11 patients, ascites-derived ovarian cancer cells (fresh and gradient isolated) were positive for this marker. The proportion of positive cells ranged from 10 to 90% in these samples. Intraperitoneal recombinant interferon-gamma (rIFN-gamma) therapy resulted in an increase in the number of cells reacting with CA 125. The results of monitoring in patients receiving different therapeutic regimens and/or agents demonstrate the usefulness of this marker.

Influence of morphology and malignancy of three new human melanoma cell lines on the cyclooxygenase pathway.

Three newly established human melanoma cell lines (WU-BI, PN-JC, MJ-ZJ) of different morphology and different stage of malignancy were incubated with ionophore A23187 (2.5 to 40 microM) or arachidonic acid (AA, 6.25 to 100 microM). PGF2 alpha, 6-keto-PGF1 alpha, PGE2, TXB2 and 2,3-dinor-TXB2 from isolated cells and supernatants were measured by negative ion chemical ionization gas chromatography/mass spectrometry (GC/MS). PGE2 decreased in the fibroblastoid MJ-ZJ cells from 36.7 ng/mg cell protein about 70% (A23187) and about 20% (AA), respectively. However, in the cell supernatant PGE2 increased up to 295.4 +/- 66.5 ng/mg cell protein. Production of PGF2 alpha and PGE2 increased up to 5.7 +/- 1.2 ng/mg cell protein for polydendritic WU-BI cells and spindle shaped PN-JC cells. Up to 9.3 +/- 4.3 ng PGF2 alpha and 13.4 +/- 4.7 ng PGE2 was measured for WU-BI and PN-JC in the cell supernatants. All three melanoma cell lines completely lacked formation of 6-keto-PGF1 alpha, TXB2, and 2,3-dinor-TXB2.

Expression of myc and ras oncogenes in two newly established neuroblastoma cell lines.

Two new neuroblastoma cell lines, KG-MH and KM-YH have been established from fresh tumour samples. In vitro growth characteristics are presented together with a karyological analysis. Northern and Southern blot experiments have been performed using molecularly cloned probes for c-myc, N-myc, c-Ha-ras, c-Ki-ras, and N-ras oncogenes. Both cell lines showed expression for N-myc, while c-myc expression was not detected. Cell line KM-YH, with a rather long population doubling time of 78 h, showed additional expression for the three ras genes.

Expression and release of interleukin-1 by different human melanoma cell lines.

The influence of immunologic parameters on the clinical course of malignant melanoma is increasingly evident. However, it is not known which factors contribute to the immunologic host reaction against malignant melanoma. Because epidermal cells and, in particular, normal as well as transformed keratinocytes recently have been demonstrated to release various immunomodulating cytokines, the capacity of melanoma cells to produce interleukin-1 (IL-1) was examined. Accordingly, supernatants derived from different melanoma cell lines contained significant levels of IL-1 activity. Upon high-performance liquid chromatography (HPLC) gel filtration, melanoma cell-derived IL-1 (MEL-IL-1) exhibited molecular weight heterogeneity, and HPLC chromatofocusing revealed major activity at pH 5.0 and minor activity at pH 7.0. A monoclonal antibody directed against monocyte-derived IL-1 blocked MEL-IL-1 activity significantly and was able to precipitate four species of biosynthetically radiolabeled MEL-IL-1 (25, 17, 6, and 4 kilodaltons), suggesting that MEL-IL-1 is identical to monocyte-derived IL-1. This was also confirmed by Northern blot analysis detecting IL-1 alpha specific mRNA in melanoma cells by hybridization with a cDNA fragment encoding for IL-1 alpha. Thus, melanoma cells, like other epidermal cells, exhibit the capacity to release the immunomodulating cytokine IL-1 and, therefore, probably have the potency to influence host defense mechanisms directed against malignant melanoma.

Purification of an active plasminogen activator inhibitor immunologically related to the endothelial type plasminogen activator inhibitor from the conditioned media of a human melanoma cell line.

24 established melanoma cell cultures were screened for their secretion of plasminogen activators and plasminogen activator inhibitors into the culture medium by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by conventional and reverse fibrin autography. Among the cell lines investigated, 22 cell lines predominantly secreting tissue type plasminogen activator (t-PA) and four cell lines additionally secreting urokinase were found. The conditioned media of two cell lines (KRFM and MJZJ) were found to contain plasminogen activator inhibitor (PAI) activity at a Mr position of approximately 50,000. The PAI of one of the two melanoma cell (MJZJ)-conditioned media found to contain PAI activity was purified to apparent homogeneity employing concanavalin A-Sepharose chromatography, gel filtration on Sephadex G-150, chromatography on Affi-Gel blue, and affinity chromatography on a Sepharose 4B immobilized monoclonal anti-t-PA IgG column. The purified melanoma PAI was found to be a single chain protein, acid stable, immunologically related to the endothelial derived PAI. In contrast to endothelial PAI, melanoma PAI presented itself in the conditioned media of the melanoma cells and in the purified preparation to an appreciable extent in its active form.