Quality of life measurement in rosacea. Position statement of the European Academy of Dermatology and Venereology Task Forces on Quality of Life and Patient Oriented Outcomes and Acne, Rosacea and Hidradenitis Suppurativa.

The European Academy of Dermatology and Venereology (EADV) Task Forces (TFs) on Quality of Life (QoL) and Patient-Oriented Outcomes and Acne, Rosacea and Hidradenitis Suppurativa (ARHS) do not recommend the use of any generic instrument as a single method of Health Related (HR) QoL assessment in rosacea, except when comparing quimp (quality of life impairment) in rosacea patients with that in other non-dermatologic skin diseases and/or healthy controls. The EADV TFs on QoL and Patient-Oriented Outcomes and ARHS recommend the use of the dermatology-specific HRQoL instrument the Dermatology Life Quality Index (DLQI) and the rosacea-specific HRQoL instrument RosaQoL in rosacea patients. The DLQI minimal clinically important difference may be used as a marker of clinical efficacy of the treatment and DLQI score banding of 0 or 1 corresponding to no effect on patients' HRQoL could be an important treatment goal. This information may be added to consensuses and guidelines for rosacea.

Artificial neural networks allow response prediction in squamous cell carcinoma of the scalp treated with radiotherapy.

BACKGROUND: Epithelial neoplasms of the scalp account for approximately 2% of all skin cancers and for about 10-20% of the tumours affecting the head and neck area. Radiotherapy is suggested for localized cutaneous squamous cell carcinomas (cSCC) without lymph node involvement, multiple or extensive lesions, for patients refusing surgery, for patients with a poor general medical status, as adjuvant for incompletely excised lesions and/or as a palliative treatment. To date, prognostic risk factors in scalp cSCC patients are poorly characterized. OBJECTIVE: To identify patterns of patients with higher risk of postradiotherapy recurrence. METHODS: A retrospective observational study was performed on scalp cSCC patients with histological diagnosis who underwent conventional radiotherapy (50-120 kV) (between 1996 and 2008, follow-up from 1 to 140 months, median 14 months). Out of the 79 enrolled patients, 22 (27.8%) had previously undergone a surgery. Two months after radiotherapy, 66 (83.5%) patients achieved a complete remission, 6 (7.6%) a partial remission, whereas 2 (2.5%) proved non-responsive to the treatment and 5 cases were lost to follow-up. Demographical and clinical data were preliminarily analysed with classical descriptive statistics and with principal component analysis. All data were then re-evaluated with a machine learning-based approach using a 4th generation artificial neural networks (ANNs)-based algorithm. RESULTS: Artificial neural networks analysis revealed four scalp cSCC profiles among radiotherapy responsive patients, not previously described: namely, (i) stage T2 cSCC type, aged 70-80 years; (ii) frontal cSCC type, aged <70 years; (iii) non-recurrent nodular or nodulo-ulcerated, stage T3 cSCC type, of the vertex and treated with >60 Grays (Gy); and (iv) flat, occipital, stage T1 cSCC type, treated with 50-59 Gy. The model uncovering these four predictive profiles displayed 85.7% sensitivity, 97.6% specificity and 91.7% overall accuracy. CONCLUSIONS: Patient profiling/phenotyping with machine learning may be a new, helpful method to stratify patients with scalp cSCCs who may benefit from a RT-treatment.

Quality of life measurement in hidradenitis suppurativa: position statement of the European Academy of Dermatology and Venereology task forces on Quality of Life and Patient-Oriented Outcomes and Acne, Rosacea and Hidradenitis Suppurativa.

This paper is organized jointly by the European Academy of Dermatology and Venereology (EADV) Task Force (TF) on Quality of Life (QoL) and Patient-Oriented Outcomes and the EADV TF on acne, rosacea and hidradenitis suppurativa (ARHS). The purpose of this paper was to present current knowledge about QoL assessment in HS, including data on HS-specific health-related (HR) QoL instruments and HRQoL changes in clinical trials, and to make practical recommendations concerning the assessment of QoL in people with HS. HS results in significant quimp that is higher than in most other chronic skin diseases. HS impact in published studies was assessed predominantly (84% of studies) by the Dermatology Life Quality Index (DLQI). There is a lack of high-quality clinical trials in HS patients where HRQoL instruments have been used as outcome measures. One double-blind randomized placebo-controlled trial on infliximab with low number of participants reported significantly better HRQoL improvement in the treatment group than in the placebo group. Well-designed clinical studies in HS patients to compare different treatment methods, including surgical methods and assessing long-term effects, are needed. Because of lack of sufficient validation, the Task Forces are not at present able to recommend existing HS-specific HRQoL instruments for use in clinical studies. The EADV TFs recommend the dermatology-specific DLQI questionnaire for use in HS patients. The EADV TFs encourage the further development, validation and use of other HS-specific, dermatology-specific and generic instruments but such use should be based on the principles presented in the previous publications of the EADV TF on QoL and Patient-Oriented Outcomes.

[Body dysmorphic disorder : Diagnostics and treatment in cosmetic dermatology]. / Körperdysmorphe Störung : Diagnostik und Therapie in der kosmetischen Dermatologie.

People with a body dysmorphic disorder (BDD) suffer from excessive preoccupation and anxiety about an imagined or to others a negligible defect in their appearance. They cannot bear to look at themselves, feel ugly, are convinced that their nose, their physique and their skin are disfiguring. The more concerned they become about their appearance, the more their attention is drawn to the ostensible blemishes and reinforces the impression of their own unattractiveness. Those affected do not consider themselves to be ill, but are convinced that it is a real physical defect which forces them again and again to stand in front of the mirror. Such patients may consult a dermatologist, some even a plastic surgeon, in order to get closer to their ideal of beauty, which perforce remains unattainable for patients because of a distorted perception of their body.

Quality of life in patients with scalp psoriasis.

AIM: The aims of this study were to describe the quality of life (QoL) in patients suffering of scalp psoriasis and to assess the impact of the socio-demographic and clinical features of this condition on patients' health-related QoL, using general and specific QoL scales. METHODS: This research is a cross-sectional study. The study involved 55 patients attending their first examination at the Dermatology Clinic of Padua University over the course of one year (April 2010-March 2011). The outcome was quality of life analyzed by means Scalpdex and SF-36 questionnaire. RESULTS: The sample's mean Scalpdex score was 43.60±17.52, while the mean SF-36 score was 68.28±20.32. The SF-36 identified statistically significant differences between the psoriasis patients and the Italian general population in two domains, i.e. general health (P=0.0075) and emotional role (P=0.0048). The severity of patients' scalp lesions emerged as a factor associated with a reduced QoL in these patients, irrespective of the severity of their disease as a whole. Sex, age, schooling and other socio-demographic factors also characterized patients' perceived QoL. CONCLUSION: Patients with scalp psoriasis suffered from a lower QoL relating to the highly visible site of their psoriatic lesions. Specific supportive measures should be dedicated to these patients by health care workers.

Seborrheic dermatitis and hypertension in adults: a cross-sectional study.

BACKGROUND: Seborrheic dermatitis (SD) is a chronic inflammatory skin disease that shares some features with psoriasis. Previous reports have demonstrated an association between hypertension and psoriasis. Chronic skin inflammation may plays a role in the aetiology of hypertension in both disorders. OBJECTIVE: To evaluate the association between SD and hypertension in an adult large population sample. METHODS: A cross-sectional study was carried out by utilizing the database of Clalit Health Services, a healthcare provider organization for over 4 million enrollees in Israel. All adult patients previously diagnosed with SD were compared with a sample of enrollees without SD regarding the prevalence of hypertension. Patients without SD were frequency matched to SD patients regarding age and sex. Data on other health-related lifestyles and comorbidities were collected. RESULTS: The study included all 9255 patients with SD and 9246 age- and sex-matched patients without SD. The prevalence of hypertension was significantly higher in patients with SD (27.1% vs. 24.7%, P < 0.001, OR = 1.13, 95% CI: 1.05-1.21). A multivariate logistic regression model demonstrated that SD was significantly associated with hypertension after controlling for confounders, including age, sex, socioeconomic status, smoking, diabetes and obesity (multivariate OR = 1.23, 95% CI: 1.12-1.35, P < 0.001). CONCLUSIONS: In this study, an association between SD and hypertension was demonstrated in adults. Many factors can be advocated to explain this association. Genetic predisposition, psychological conditions, lipid abnormalities and chronic inflammation of the skin with a change in cytokine balance should be explored as potential mechanisms.

Angiokeratoma: decision-making aid for the diagnosis of Fabry disease.

Isolated angiokeratomas are common benign cutaneous lesions, generally deemed unworthy of further investigation. In contrast, diffuse angiokeratomas should alert the physician to a possible diagnosis of Fabry disease, a rare X-linked lysosomal storage disorder, characterized by α-galactosidase deficiency. Glycosphingolipids accumulate in cells throughout the body resulting in progressive multi-organ failure. Difficulties are encountered when trying to interpret the significance of angiokeratomas because they may also occur in other lysosomal storage disorders and rarely in an isolated manner in Fabry disease. We present an algorithm for the classification of angiokeratomas which might prove useful for the diagnosis and management of Fabry disease. Assessment of the clinical features and location of the lesions, personal and family history, skin biopsy, dermoscopy and electron microscopy imaging are sequential steps in the diagnostic process. Assessing the deficiency of α-galactosidase enzyme activity is essential to confirm the diagnosis in males, while mutation analysis is always needed in females. Potentially this algorithm can change the current approach to patients when Fabry disease is suspected, thus improving the diagnostic strategy and management of this disorder. It remains to be decided whether the use of an algorithm might reduce the number of genetic consultations. As evidence has shown the efficacy of enzyme replacement therapy in halting progression of the disease before the onset of irreversible organ damage, it is advisable to aim at an early diagnosis in order to achieve timely initiation of effective treatment with benefits for patients and appropriate use of medical resources.

Generalized granuloma annulare treated with methylaminolevulinate photodynamic therapy.

Granuloma annulare (GA) is a non-infectious granulomatous dermatosis characterized by annular papules and rarely nodules and plaques, arising on the dorsa of the hands, feet, elbows and knees; it is usually chronic and asymptomatic. The aetiology of GA is unknown, although many hypotheses have been postulated. About 10% of patients affected by GA present the generalized subtype, characterized by a later age of onset and a chronic course with a low tendency to spontaneous resolution. The widespread papular eruption develops on the trunk and upper or lower limbs. Generalized GA is very disfiguring because of the extensive dissemination of the lesions. The response to various treatments, namely topical and intralesional corticosteroids, topical tacrolimus, dapsone, isotretinoin, etretinate or hydroxychloroquine, is usually unsatisfactory. We report 3 cases with long-lasting generalized GA responding to methylaminolevulinate photodynamic therapy.

Topical corticosteroid therapy for acute radiation dermatitis: a prospective, randomized, double-blind study.

BACKGROUND: Radiation dermatitis is a common side-effect of radiation therapy, but there is no current consensus about its appropriate therapy. OBJECTIVES: To compare treatment with topical 0.1% methylprednisolone vs. 0.5% dexpanthenol in a cohort of patients undergoing fractionated radiation therapy for breast cancer. METHODS: In a randomized, double-blind design, treatment was initiated at the beginning of radiation therapy and continued for 2 weeks after termination of radiation. Outcomes were compared by three different measures: clinical (symptom score), functional (transepidermal water loss, TEWL) and subjective (quality of life, QOL). RESULTS: In a preliminary cohort of untreated patients undergoing radiation therapy, clinical signs and TEWL levels increased progressively during radiation therapy, reaching highest values at 5 and 4 weeks, respectively. Although neither topical treatment reduced the incidence of radiation dermatitis, both delayed the emergence of greatest clinical and TEWL scores until approximately 6 and 5 weeks, respectively. With topical corticosteroids, clinical symptoms and TEWL were less pronounced than with dexpanthenol. Whereas general QOL improved after completion of radiation therapy, skin-related QOL declined. However, the skin-related QOL decline could be at least in part reversed by use of topical corticosteroid vs. dexpanthenol-containing emollient. CONCLUSIONS: We provide evidence that prophylactic and ongoing use of topical therapy with either topical corticosteroid or a dexpanthenol-containing emollient ameliorates, but does not prevent radiation dermatitis. Our data suggest, but do not prove, a benefit of a topical corticosteroid vs. a dexpanthenol-containing emollient. Further controlled studies with larger cohorts will be needed to determine optimal forms of topical therapy for radiation dermatitis.

Permeability barrier function of skin exposed to ionizing radiation.

OBJECTIVE: To characterize the epidermal permeability barrier function of skin during exposure to ionizing radiation. DESIGN: A prospective cohort study. SETTING: University hospital medical center. PATIENTS: Fifteen women receiving local radiation therapy (5000-6000 rad [50-60 Gy]) following breast-conserving surgery for breast cancer. MAIN OUTCOME MEASURES: Clinical symptoms and transepidermal water loss (TEWL). RESULTS: Epidermal permeability barrier function is impaired in patients who exhibit clinical signs of radiation dermatitis. The functional damage to the stratum corneum induced by ionizing radiation occurs with a delayed course, starting within a mean period of 11 days and reaching maximal values after a mean period of 27 days (range, 13-75 days). The onset of TEWL increase precedes the onset of radiation dermatitis and the maximal TEWL measurements precede the peak of skin changes. Patients with an early onset of TEWL increase show a longer duration of skin symptoms. CONCLUSIONS: Skin changes caused by radiation dermatitis are associated with an increase in TEWL. The barrier impairment is comparable to the changes observed with UV radiation exposure but exhibits an even more delayed course. Our results suggest that preservation of the epidermal permeability barrier function by topical treatment may ameliorate radiation dermatitis.

A family of secreted mucins from the parasitic nematode Toxocara canis bears diverse mucin domains but shares similar flanking six-cysteine repeat motifs.

Infective larvae of the parasitic nematode Toxocara canis secrete a family of mucin-like glycoproteins, which are implicated in parasite immune evasion. Analysis of T. canis expressed sequence tags identified a family of four mRNAs encoding distinct apomucins (Tc-muc-1-4), one of which had been previously identified in the TES-120 family of glycoproteins secreted by this parasite. The protein products of all four cDNAs contain signal peptides, a repetitive serine/threonine-rich tract, and varying numbers of 36-amino acid six-cysteine (SXC) domains. SXC domains are found in many nematode proteins and show similarity to cnidarian (sea anemone) toxins. Antibodies to the SXC domains of Tc-MUC-1 and Tc-MUC-3 recognize differently migrating members of TES-120. TES-120 proteins separated by chromatographic methods showed distinct amino acid composition, mass, and sequence information by both Edman degradation and matrix-assisted laser desorption ionization/time of flight mass spectrometry on peptide fragments. Tc-MUC-1, -2, and -3 were shown to be secreted mucins with real masses of 39.7, 47.8, and 45.0 kDa in contrast to their predicted peptide masses of 15.7, 16.2, and 26.0 kDa, respectively. The presence of SXC domains in all mucin products supports the suggestion that the SXC motif is required for mucin assembly or export. Homology modeling indicates that the six-cysteine domains of the T. canis mucins adopt a similar fold to the sea anemone potassium channel-blocking toxin BgK, forming three disulfide bonds within each subunit.

Turkey cytochrome c oxidase contains subunit VIa of the liver type associated with low efficiency of energy transduction.

Cytochrome c oxidase was isolated from turkey liver, heart and breast skeletal muscle and separated by SDS/PAGE. The N-terminal amino-acid sequence of subunit VIa from all tissues and internal sequences from the skeletal muscle enzyme show homology to the mammalian liver-type subunit VIaL, which was verified by isolation and sequencing of the cDNA of turkey subunit VIa. No cDNA corresponding to subunit VIaH (mammalian heart-type) could be found by RACE-PCR with mRNA from all turkey tissues. Measurement of proton translocation with the reconstituted enzymes from turkey liver and heart revealed H+/e- ratios below 0.5 that were independent of the intraliposomal ATP/ADP ratio, as previously found with the bovine liver enzyme. Under identical conditions, the bovine heart enzyme revealed H+/e- ratios of 0.85 at low and 0.48 at high intraliposomal ATP/ADP ratios. The results suggest that in birds the lower H+/e-ratio of cytochrome c oxidase participates in elevated resting metabolic rate and thermogenesis.

Biological therapies for breast carcinoma: concepts for improvement in survival.

Systemic treatments for breast carcinoma have improved substantially over the past quarter century. New insights into cancer biology, refinements in biotechnology, and bioengineering of macromolecules hold the promise of even greater reductions in breast and other cancer mortality as a result of biologicals. As exemplified by the clinical results with the monoclonal antibody to HER-2 for antigen-specific passive immunotherapy, biological therapies for breast carcinoma hold substantial promise. The objective of this report is to highlight aspects of preclinical and clinical research on other biologicals for breast carcinoma that also hold potential for improving patient survival. As examples of the potential of cytokines to modulate breast carcinoma cell proliferation and tumor growth, data on cytokines (interferons) with pleiotropic effects and a lymphokine (interleukin-10) acting on T cells and macrophages will be reviewed. HER-2 has promise as a vaccine for active specific immunotherapy; these data will be summarized. Progress on these and other biologicals promises that this will be another modality of therapy resulting in improved survival for patients with both early and metastatic breast carcinoma in the next millennium.

Determination of the disulfide bonds within a B domain variant surface glycoprotein from Trypanosoma congolense.

The disulfide bonds within a variant surface glycoprotein from Trypanosoma congolense have been determined. L-[35S]Cysteine metabolically labeled protein was digested with trypsin, and radiolabeled peptides were separated by reversed-phase high performance liquid chromatography, and putative cystine-containing peptides were subdigested with other proteases and analyzed after further purification by amino acid sequencing and mass spectrometry. All eight cysteine residues of the protein, located within the N-terminal domain, are covalently linked. The four disulfide bonds are between cysteines 16/236, 171/193, 195/206, and 286/298. This is, for the first time, the determination of disulfide bonds within a variant surface glycoprotein belonging to the B-type. As all the eight cysteines of BENat 1.3 variant surface glycoprotein are positionally conserved, the cystine pattern of this protein can be regarded as a prototype of disulfide bonding within B-type variant surface glycoproteins. Although the cysteine residues of B-type variant surface glycoproteins are located at completely different positions in the protein chain compared with A-type variant surface glycoproteins, the positions of the disulfide bonds can easily be integrated into the A-type tertiary structure. This result implies that, despite their enormous amino acid sequence variability, variant surface glycoproteins, regardless of their subtype, can fold into a similar tertiary structure.

Structure and glycosylation patterns of surface proteins from woodchuck hepatitis virus.

Woodchucks chronically infected with woodchuck hepatitis virus (WHV) are a valuable model for human hepatitis B virus (HBV) in studies of pathogenesis, immunity, and antiviral therapy. For this reason, substantial efforts to characterize both the similarities and the differences between HBV and WHV are being made. The structure of the WHV surface proteins (WHs proteins) has not yet been adequately elucidated. The bands that would be expected for glycosylated and nonglycosylated small (S) WHs protein are found by sodium dodecyl sulfate gel electrophoresis of purified WHs protein, but the bands corresponding to the middle (M) and large (L) WHs proteins of HBV are not seen at the expected sizes, even though the sequences of the WHV and HBV surface protein genes are 60% homologous. By amino-terminal sequencing we have identified two bands at 41 and 45 kDa as the MWHs proteins, 8 kDa larger than expected. We have also confirmed that two bands at 24 and 27 kDa are SWHs proteins. A protein of 49 kDa was blocked at the N terminus, which using immunoblotting with an antiserum against WHV pre-S1 (positions 126 to 146) was identified, together with a part of the 45-kDa protein, as glycosylated and nonglycosylated LWHs protein of the expected size. Sialidase and O-glycosidase digestion showed that the larger size of MWHs protein results from the presence of O glycoside groups which are probably in the pre-S2 domain of MWHs protein. Since the pre-S2 domains of HBV and WHV have similar numbers of potential O glycosylation sites, it appears to be likely that the glycosyltransferases act differently on the viral proteins in woodchucks and humans.

Membrane dipeptidase and glutathione are major components of pig pancreatic zymogen granules.

Membrane proteins of highly purified porcine zymogen granules were separated by two-dimensional gel electrophoresis in order to isolate proteins which are involved in intracellular trafficking of digestive enzymes in the exocrine pancreas. A 48-kDa glycoprotein was a major component in membrane preparations washed with 0.1 M Na2CO3 and 0.5 M NaCl. By N-terminal amino acid sequencing this protein was identified as membrane dipeptidase (MDP; EC 3.4.13.19). MDP mRNA levels in rat pancreas were increased threefold by feeding rats with FOY-305, which is a known stimulus of endogenous cholecystokinin release from the gut. Cholecystokinin then stimulates secretion in pancreatic acinar cells. In another set of experiments treatment of the rat pancreatic acinar tumor cell line AR42J with dexamethasone led to an eightfold increase in the expression of MDP. Thus, the expression pattern of the MDP gene in response to hormonal stimulation in vivo and in vitro resembles those found for most of the enzymes and proteins which are involved in secretion. Since MDP has been thought to have a role in glutathione (GSH) metabolism, we also measured GSH concentration in zymogen granules and found high levels of GSH. Based on our data we propose a working model for the function of MDP. According to this model, MDP might play a pivotal role in maintaining the oxidizing conditions in the ER, which are required for the correct folding of secretory proteins.

A specific binding protein for cardiac glycosides exists in bovine serum.

Searching for a binding protein in blood, which may be involved in the specific transport of cardiac glycosides to their receptor sites on the sodium pump, we isolated a cardiac glycoside-binding protein (CGBG) of 26 kDa from the globulin fraction of bovine serum by affinity chromatography and on a ouabain-Sepharose 4B column by a purification factor of 5000. The cardiac glycoside-binding globulin was labeled specifically and covalently by the protein-reactive digoxigenin derivative HDMA (N-hydroxysuccimidyldigoxigenin-3-O-methylcarbonyl-epsilon-+ ++aminocapro ate). Even very high concentrations of other steroids, such as estrogen, testosterone, progesterone, and cortisone, did not prevent HDMA-labeling (at 5 and 100 nM) of CGBG, but the cardenolides ouabain and digoxin or the bufadienolide proscillaridin A did so. CGBG is a homodimer of two 26-kDa subunits forming disulfide bonds, since HDMA labeling of a protein of 53 kDa was observed in SDS-polyacrylamide gel electrophoresis when beta-mercaptoethanol was absent during SDS denaturation. The N-terminal amino acid sequence K-D-V-Y-R-A-P-D-G-T-Q-S-A showed no sequence similarity with proteins recorded in gene and protein sequence data banks. A 90-kDa cytosolic CGBG exists in bovine kidneys and reacts with antibodies against CGBG. Binding of ouabain to the cardiac glycoside-binding globulin was monitored by quenching of intrinsic tryptophan fluorescence. Such studies reveal two negatively cooperative ouabain binding sites with Kd' of 1.52 nM and Kd' = 75 nM and with an interaction factor of 50 using a Koshland-Némethy-Filmer model. The demonstration of a cardiac glycoside-binding globulin in plasma is consistent with the recent finding of endogenous cardiac glycosides in mammals.

Limited plasmin proteolysis of vitronectin. Characterization of the adhesion protein as morpho-regulatory and angiostatin-binding factor.

The adhesion protein vitronectin is associated with extracellular matrices and serves as cofactor for plasminogen-activator inhibitor-1. Limited proteolysis by plasmin converts vitronectin into defined fragments which are detectable at sites of inflammation and angiogenesis. The loss and gain of binding functions of vitronectin fragments for macromolecular ligands was characterized in the present study. The initially generated 61--63-kDa vitronectin-(1--348)-fragment serves as typical binding component for plasminogen and binding function was lost upon carboxypeptidase B treatment indicating the importance of a C-terminal lysine. Complementary binding sites reside in isolated plasminogen kringles 1--3 (designated angiostatin) as deduced from direct binding and ligand blotting experiments. A synthetic vitronectin-(331--348)-peptide from the C-terminus of the 61--63-kDa fragment could mimic plasminogen and angiostatin binding. Also, the immobilized peptide bound tissue plasminogen-activator and mediated plasmin formation, comparable to fibrinogen-derived peptides. The 61--63-kDa vitronectin fragment was indistinguishable in its adhesive properties to intact vitronectin and bound active but not latent plasminogen-activator inhibitor-1. Late plasminolysis of vitronectin resulted in the processing of the N-terminal region of the protein with the generation of 42 kDa/35-kDa fragments that had Gly89 as new N-terminus and that were ineffective in promoting cell adhesion. Thus, at sites of cell-matrix interactions which become proteolytically modified by plasmin during inflammatory and angiogenic processes, vitronectin serves as plasminogen/angiostatin-binding factor. Due to this differential change in functions particularly at sites of deposition in the vascular system or at wound sites vitronectin is considered to be an important morpho-regulatory factor.

Chemosensitivity testing of human tumors using a microplate adenosine triphosphate luminescence assay: clinical correlation for cisplatin resistance of ovarian carcinoma.

An ATP luminescence assay (TCA 100) was used to measure chemotherapeutic drug sensitivity and resistance of dissociated tumor cells cultured for 6 days in serum-free medium and 96-well polypropylene microplates. Studies were performed with surgical, needle biopsy, pleural, or ascitic fluid specimens using 10,000-20,000 cells/well. ATP measurements were used to determine tumor growth inhibition. Single agent and drug combinations were evaluated using the area under the curve and 50% inhibitory concentration (IC50) results for a series of test drug concentrations. The ATP luminometry method had high sensitivity, linearity, and precision for measuring the activity of single agents and drug combinations. Assay reproducibility was high with intraassay and interassay coefficients of variation of 10-15% for percentage of tumor growth inhibition, 5-10% for area under curve, and 15-20% for IC50 results. Good correlation (r = 0.93) between the area under the curve, and IC50 results was observed. Cytological studies with 124 specimens demonstrated selective growth of malignant cells in the serum-free culture system. Studies with malignant and benign specimens also showed selective growth of malignant cells in the serum-free medium used for assay. The assay had a success rate of 87% based on criteria for specimen histopathology, magnitude of cell growth, and dose-response drug activity. Cisplatin results for ovarian carcinoma are presented for 81 specimens from 70 untreated patients and 33 specimens from 30 refractory patients. A model for interpretation of these results based on the correlation of clinical response with the area under the curve and IC50 results indicates that the assay has > 90% accuracy for cisplatin resistance of ovarian carcinoma. Additional studies are in progress to evaluate the clinical efficacy of this assay.