Bioinspired and Bioderived Aqueous Electrocatalysis

The development of efficient and sustainable electrochemical systems able to provide clean-energy fuels and chemicals is one of the main current challenges of materials science and engineering. Over the last decades, significant advances have been made in the development of robust electrocatalysts for different reactions, with fundamental insights from both computational and experimental work. Some of the most promising systems in the literature are based on expensive and scarce platinum-group metals; however, natural enzymes show the highest per-site catalytic activities, while their active sites are based exclusively on earth-abundant metals. Additionally, natural biomass provides a valuable feedstock for producing advanced carbonaceous materials with porous hierarchical structures. Utilizing resources and design inspiration from nature can help create more sustainable and cost-effective strategies for manufacturing cost-effective, sustainable, and robust electrochemical materials and devices. This review spans from materials to device engineering; we initially discuss the design of carbon-based materials with bioinspired features (such as enzyme active sites), the utilization of biomass resources to construct tailored carbon materials, and their activity in aqueous electrocatalysis for water splitting, oxygen reduction, and CO₂ reduction. We then delve in the applicability of bioinspired features in electrochemical devices, such as the engineering of bioinspired mass transport and electrode interfaces. Finally, we address remaining challenges, such as the stability of bioinspired active sites or the activity of metal-free carbon materials, and discuss new potential research directions that can open the gates to the implementation of bioinspired sustainable materials in electrochemical devices.

Controlling and Optimizing Photoinduced Charge Transfer across Ultrathin Silica Separation Membrane with Embedded Molecular Wires for Artificial Photosynthesis

Ultrathin amorphous silica membranes with embedded organic molecular wires (oligo(p-phenylenevinylene), three aryl units) provide chemical separation of incompatible catalytic environments of CO₂ reduction and H₂O oxidation while maintaining electronic and protonic coupling between them. For an efficient nanoscale artificial photosystem, important performance criteria are high rate and directionality of charge flow. Here, the visible-light-induced charge flow from an anchored Ru bipyridyl light absorber across the silica nanomembrane to Co₃O₄ water oxidation catalyst is quantitatively evaluated by photocurrent measurements. Charge transfer rates increase linearly with wire density, with 5 nm^-2 identified as an optimal target. Accurate measurement of wire and light absorber densities is accomplished by the polarized FT-IRRAS method. Guided by density functional theory (DFT) calculations, four wire derivatives featuring electron-donating (methoxy) and -withdrawing groups (sulfonate, perfluorophenyl) with highest occupied molecular orbital (HOMO) potentials ranging from 1.48 to 0.64 V vs NHE were synthesized and photocurrents evaluated. Charge transfer rates increase sharply with increasing driving force for hole transfer from the excited light absorber to the embedded wire, followed by a decrease as the HOMO potential of the wire moves beyond the Co₃O₄ valence band level toward more negative values, pointing to an optimal wire HOMO potential around 1.3 V vs NHE. Comparison with photocurrents of samples without nanomembrane indicates that silica layers with optimized wires are able to approach undiminished electron flux at typical solar intensities. Combined with the established high proton conductivity and small-molecule blocking property, the charge transfer measurements demonstrate that oxidation and reduction catalysis can be efficiently integrated on the nanoscale under separation by an ultrathin silica membrane.

Influence of patient and tumor characteristics on early therapy persistence with letrozole in postmenopausal women with early breast cancer: results of the prospective Evaluate-TM study with 3941 patients

Background

Patients' compliance and persistence with endocrine treatment has a significant effect on the prognosis in early breast cancer (EBC). The purpose of this analysis was to identify possible reasons for non-persistence, defined as premature cessation of therapy, on the basis of patient and tumor characteristics in individuals receiving adjuvant treatment with letrozole.

Patients and methods

The EvAluate-TM study is a prospective, multicenter, noninterventional study in which treatment with the aromatase inhibitor letrozole was evaluated in postmenopausal women with hormone receptor-positive EBC in the early therapy phase. Treatment persistence was evaluated at two pre-specified study visits after 6 and 12 months. As a measure of early therapy persistence the time from the start to the end of treatment (TTEOT) was analyzed. Cox regression analyses were carried out to identify patient characteristics and tumor characteristics predicting TTEOT.

Results

Out of the total population of 3941 patients with EBC, 540 (13.7%) events involving treatment cessation unrelated to disease progression were observed. This was due to drug-related toxicity in the majority of cases (73.5%). Persistence rates were 92.2%, 86.9%, and 86.3% after 6, 12, and 15 months, respectively. The main factors influencing premature treatment discontinuation were older age [hazard ratio (HR) 1.02/year], comorbidities (HR 1.06 per comorbidity), low body mass index, and lower tumor grade (HR 0.85 per grade unit).

Conclusion

These results support the view that older, multimorbid patients with low tumor grade and low body mass index are at the greatest risk for treatment discontinuation and might benefit from compliance and support programs.

Abstract P1-13-01: Final results of the ASG1-3 study, a randomized phase III study comparing a standard dose chemotherapy with epirubicin/cyclophosphamide and paclitaxel with a dose dense regimen with epirubicin and paclitaxel

Background

Dose dense chemotherapy (DDT) has shown improvements of disease-free survival (DFS) and overall survival for primary breast cancer patients with a high risk of relapse. There are much less data about the effect of DDT in patients with intermediate risk of recurrence (1-3 positive axillary lymph nodes). Aim of this prospectively randomized trial was to investigate the superiority of a DDT schedule over a standard chemotherapy (ST) in primary breast cancer patients with 1-3 positive axillary lymph nodes.

Methods

The ASG1-3 study is a prospectively randomized, open label phase III study of the Adjuvant Study Group of the NOGGO association. Patients were eligible for the trial, if they had a primary invasive breast cancer (pT1-3) with 1-3 positive axillary lymph nodes and no evidence of distant metastases. Patients were randomized to an adjuvant therapy with either 4 cycles epirubicin (90mg/m2 body surface area, BSA) and cyclophosphamide (600mg/m2 BSA) q3w, followed by 4 cycles of paclitaxel (175mg/m2 BSA) referred to as ST or to a therapy with 4 cycles of epicubicin (120 mg/m2 BSA) q2w and primary G-CSF support followed by 4 cycles of paclitaxel (175mg/m2 BSA) q2w and primary G-CSF support referred to as DDT. Trastuzumab was not given in this study. The study was designed to show an increase of 70% DFS (ST) to 80% DFS (DDT) 5 years after randomization. Comparisons were conducted using Kaplan Meier estimates, log rank tests and Cox regression analyses. In an exploratory way, subgroup analyses were performed for HER2, hormone receptor status and grading using Cox regression models with interaction terms.

Results

A total of 936 patients were eligible for survival analysis, of which 465 were randomized to ST and 471 to DDT from 2001 to 2004. Patient characteristics were mainly well balanced, with patients being 52.5/52.1 years old, 71.9/78.1% being hormone receptor positive, 24.4/24.6% being HER2 positive and 38.6/38.8% having a tumor grade of 3 in the ST arm and DDT arm respectively. 53 events occurred after ST and 46 after DDT. Adjusted hazard ratio (HR) was 0.87 (95%CI: 0.57-1.35; p=0.54). 5 year DFS rates were 85% (ST) vs. 87% (DDT). Hematological toxicities were the most common grade 3 or 4 adverse events. Grade 3/4 neutropenia occurred in 57.2 vs. 28.0%, grade 3/4 anemia in 15.3% vs. 17.1% and grade 3 /4 pain symptoms were seen in 13.2 vs. 12.4% of the patients in the ST arm vs. DDT arm respectively. Other grade 3/4 toxicities were less frequent than 10%. Subgroup analysis showed a significant interaction (p<0.001) between HER2 status and randomization arm with regard to DFS. In HER2 negative patients the HR was 1.53 (95%CI: 0.91-2.59), whereas in HER2 positive patients the HR was 0.22 (95%CI: 0.09-0.55). Patients with HER2 positive disease and DDT had a similar prognosis like HER2 negative patients.

Conclusion

In the overall population a statistically significant improvement of DFS could not be shown for the DDT arm. In patients with HER2 positive breast cancer DDT chemotherapy improved the disease-free survival to a prognosis which was similar to patients with HER2 negative disease.

Citation Format: Fasching PA, Eggemann H, Krocker J, Häberle L, Volz B, Kleine-Tebbe A, Blohmer J-U, Kittel K, Hufnagel M, Janni W, Emons G, Simon E, Köhler U, Thomssen C, Kohls A, Beckmann MW, Hielscher C, Krabisch P, Zeiser T, Brodkorb T, Baier F, Nabieva N, Kellner S, Untch M, Stadie S, Budner M, Breitbach G-P, Keller M, Stickeler E, Kühn T, Tolkmitt M, Belau AK, Schmidt M, Ulm K, Kümmel S. Final results of the ASG1-3 study, a randomized phase III study comparing a standard dose chemotherapy with epirubicin/cyclophosphamide and paclitaxel with a dose dense regimen with epirubicin and paclitaxel [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-13-01.

[From myxomas of the skin to LVAD implantation : A 28-year-old female patient with Carney complex]

Multiple skin lesions, endocrine dysfunction and cardiac myxomas are characteristic symptoms of Carney complex. This case report gives an overview about the major and minor criteria of Carney complex and presents the course of a female patient who developed severe cardiac insufficiency with multiple organ failure because of recurring heart operations leading to implantation of a left ventricular assist device (LVAD).

In non-transformed cells Bak activates upon loss of anti-apoptotic Bcl-XL and Mcl-1 but in the absence of active BH3-only proteins

Mitochondrial apoptosis is controlled by proteins of the B-cell lymphoma 2 (Bcl-2) family. Pro-apoptotic members of this family, known as BH3-only proteins, initiate activation of the effectors Bcl-2-associated X protein (Bax) and Bcl-2 homologous antagonist/killer (Bak), which is counteracted by anti-apoptotic family members. How the interactions of Bcl-2 proteins regulate cell death is still not entirely clear. Here, we show that in the absence of extrinsic apoptotic stimuli Bak activates without detectable contribution from BH3-only proteins, and cell survival depends on anti-apoptotic Bcl-2 molecules. All anti-apoptotic Bcl-2 proteins were targeted via RNA interference alone or in combinations of two in primary human fibroblasts. Simultaneous targeting of B-cell lymphoma-extra large and myeloid cell leukemia sequence 1 led to apoptosis in several cell types. Apoptosis depended on Bak whereas Bax was dispensable. Activator BH3-only proteins were not required for apoptosis induction as apoptosis was unaltered in the absence of all BH3-only proteins known to activate Bax or Bak directly, Bcl-2-interacting mediator of cell death, BH3-interacting domain death agonist and p53-upregulated modulator of apoptosis. These findings argue for auto-activation of Bak in the absence of anti-apoptotic Bcl-2 proteins and provide evidence of profound differences in the activation of Bax and Bak.

[Inherited retinal or optic nerve disorders – five steps to diagnosis]

An early diagnosis of inherited retinal or optic nerve disorders is often delayed due to unspecific clinical signs, multiple clinical manifestations and striking genetic heterogeneity of the underlying molecular defects. This study represents a retrospective analysis of findings in 4,021 patients with inherited retinal or optic nerve disorders seen between 1986 and 2014 (1,171 with follow-up). In addition to the basic ophthalmological examination, electrophysiological tests (ERG, n = 2,088, since 1986; EOG, n = 381, since 1986; VEP n = 595, since 1986; mfERG, n = 819, since 1998) and non-invasive retinal imaging (fundus autofluorescence (FAF, n = 1,784, since 2002), near-infrared autofluorescence (NIA, n = 1,091, since 2006), spectral domain OCT (SD-OCT, n = 848, since 2008) and three-wavelengths multicolour spectral reflection imaging (MC, n = 366, since 2013) were performed at least once. Molecular DNA testing was done in 383 patients between 2006 and 2014. Based on these data an efficient diagnostic strategy is suggested: 1) inclusion of inherited retinal and optic nerve disorders into the differential diagnosis of visual loss or visual field defects with undefined causes; 2) non-invasive retinal imaging; 3) electrophysiological tests; 4) DNA testing to confirm the initial clinical diagnosis; 5) examination in specialised centres, therapy and follow-up. In recent years, the spectrum of diagnostic techniques has continuously expanded. Importantly, non-invasive retinal imaging has become the primary diagnostic tool and DNA testing based on state-of-the-art high throughput techniques increases the identification of associated gene mutations. In conclusion, a structured process in the diagnostic procedure of inherited retinal and optic nerve disorders greatly reduces a diagnostic delay, enables an earlier counselling and therapy and avoids further unnecessary diagnostic tests.

Evaluation of Therapy Management and Patient Compliance in Postmenopausal Patients with Hormone Receptor-positive Breast Cancer Receiving Letrozole Treatment: The EvaluateTM Study

Introduction: The EvaluateTM study (Evaluation of therapy management and patient compliance in postmenopausal hormone receptor-positive breast cancer patients receiving letrozole treatment) is a prospective, non-interventional study for the assessment of therapy management and compliance in the routine care of postmenopausal women with invasive hormone receptor-positive breast cancer receiving letrozole. The parameters for inclusion in the study are presented and discussed here. Material and Methods: Between January 2008 and December 2009 a total of 5045 patients in 310 study centers were recruited to the EvaluateTM study. Inclusion criteria were hormone receptor-positive breast cancer and adjuvant treatment or metastasis. 373 patients were excluded from the analysis for various reasons. Results: A total of 4420 patients receiving adjuvant treatment and 252 patients with metastasis receiving palliative treatment were included in the study. For 4181 patients receiving adjuvant treatment, treatment with the aromatase inhibitor letrozole commenced immediately after surgery (upfront). Two hundred patients had initially received tamoxifen and started aromatase inhibitor treatment with letrozole at 1-5 years after diagnosis (switch), und 39 patients only commenced letrozole treatment 5-10 years after diagnosis (extended endocrine therapy). Patient and tumor characteristics were within expected ranges, as were comorbidities and concurrent medication. Conclusion: The data from the EvaluateTM study will offer a good overview of therapy management in the routine care of postmenopausal women with hormone receptor-positive breast cancer. Planned analyses will look at therapy compliance and patient satisfaction with how information is conveyed and the contents of the conveyed information.

Decreased expression of MLH1, MSH2, PMS1 and PMS2 in pigmented lesions indicates accumulation of failed DNA repair along with malignant transformation and tumour progression

The tumorigenesis of human nonpolyposis colorectal cancer was reported to be connected with the mutations in DNA mismatch repair genes. The main aim of this study was to check the epression of 4 proteins MLH1, MSH2, PMS1 and PMS2 responsible for mismatch DNA repair in naevi and melanomas. Fifty-one naevi, 78 primary melanomas, 30 lymphatic and 7 organ melanoma metastases were stained for the presence of MLH1, MSH2, PMS1 and PMS2. All proteins were preserved in 88% of naevi and only in 37% of primary melanomas, 17% of lymphatic metastases and in none of the distant metastases. The difference of expression of all 4 proteins between naevi and melanomas was highly significant (p<0.01). MLH1 and MSH2 correlated significantly with each other as well with the follow-up of patients. On the basis of our results one can conclude that the defect of mismatch DNA repair plays an important role in both tumorigenesis of melanoma and metastatic spread of tumour.

Lipofuscin- and melanin-related fundus autofluorescence visualize different retinal pigment epithelial alterations in patients with retinitis pigmentosa

AIMS

To compare melanin-related near-infrared fundus autofluorescence (FAF; NIA, excitation 787 nm, emission >800 nm) with lipofuscin-related FAF (excitation 488 nm, emission >500 nm) in retinitis pigmentosa (RP).

METHODS

Thirty-three consecutive RP patients with different modes of inheritance were diagnosed clinically, with full-field ERG, and if possible with molecular genetic methods. FAF and NIA imaging were performed with a confocal scanning laser ophthalmoscope (Heidelberg Retina Angiograph 2).

RESULTS

Rings of increased FAF were present within an area of preserved retinal pigment epithelium (RPE) at the posterior pole (31/33). Rings of increased NIA were located in the same region as rings of increased FAF. In contrast to FAF, NIA showed a precipitous decline of NIA peripheral to the ring. In larger areas of preserved NIA (11/31), pericentral and foveal NIA were of similar intensity with an area of lower NIA in between. In smaller areas of preserved NIA (20/31), NIA was homogeneous from the perifovea to the fovea. In one patient without a ring of increased FAF, NIA distribution was normal. In the remaining patient with severely advanced RP, no residual RPE as well as no FAF and NIA were detectable.

CONCLUSION

Characteristic features for FAF and NIA alterations in a heterogeneous group of RP patients indicate a common pathway of RPE degeneration. Patterns of NIA and FAF indicate different pathophysiologic processes involving melanin and lipofuscin. Combined NIA and FAF imaging will provide further insight into the pathogenesis of RP and non-invasive monitoring of future therapeutic interventions.

Paroxetine Serum Concentrations in Depressed Patients and Response to Treatment

INTRODUCTION

There is no established relationship between the serum concentration of selective serotonin reuptake inhibitors (SSRIs) and clinical response in depressed patients.

METHODS

We analyzed paroxetine concentrations in serum of 46 depressed patients during treatment with a fixed dosage of 40 mg paroxetine.

RESULTS

After 5 weeks 29 patients responded to treatment, while 17 did not. Analysis of variance with repeated measures (ANOVA-rm) revealed a significant effect of "response" with responders having lower serum concentrations throughout the treatment period, when compared to non-responders. After 2, 3, and 4 weeks of treatment, we could define an upper threshold of paroxetine serum concentrations (week 1 : 22.7 ng/mL; week 2 : 43 ng/mL; week 3 : 53.4 ng/mL; week 4 : 39.1 ng/mL) above which response to treatment was unlikely.

CONCLUSION

We conclude that -- in contrast to other pharmacological approaches -- high rather than low drug serum concentrations may be associated with non-response in paroxetine treatment of depressed patients.

Binding of flavin adenine dinucleotide to molybdenum-containing carbon monoxide dehydrogenase from Oligotropha carboxidovorans. Structural and functional analysis of a carbon monoxide dehydrogenase species in which the native flavoprotein has been replaced by its recombinant counterpart produced in Escherichia coli

The carbon monoxide (CO) dehydrogenase of Oligotropha carboxidovorans is composed of an S-selanylcysteine-containing 88. 7-kDa molybdoprotein (L), a 17.8-kDa iron-sulfur protein (S), and a 30.2-kDa flavoprotein (M) in a (LMS)(2) subunit structure. The flavoprotein could be removed from CO dehydrogenase by dissociation with sodium dodecylsulfate. The resulting M(LS)(2)- or (LS)(2)-structured CO dehydrogenase species could be reconstituted with the recombinant apoflavoprotein produced in Escherichia coli. The formation of the heterotrimeric complex composed of the apoflavoprotein, the molybdoprotein, and the iron-sulfur protein involves structural changes that translate into the conversion of the apoflavoprotein from non-FAD binding to FAD binding. Binding of FAD to the reconstituted deflavo (LMS)(2) species occurred with second-order kinetics (k(+1) = 1350 M(-1) s(-1)) and high affinity (K(d) = 1.0 x 10(-9) M). The structure of the resulting flavo (LMS)(2) species at a 2.8-A resolution established the same fold and binding of the flavoprotein as in wild-type CO dehydrogenase, whereas the S-selanylcysteine 388 in the active-site loop on the molybdoprotein was disordered. In addition, the structural changes related to heterotrimeric complex formation or FAD binding were transmitted to the iron-sulfur protein and could be monitored by EPR. The type II 2Fe:2S center was identified in the N-terminal domain and the type I center in the C-terminal domain of the iron-sulfur protein.

Relation between two independent DNA-repair pathways in different groups of naevi

The relation between 2 DNA-repair systems was investigated in 3 groups of naevi (naevus cell naevi, dysplastic naevi, fibromatous naevi) using the correlation coefficient according to Spearman. In the group of naevus cell naevi, only 1 significant correlation between MSH2 and GADD34 expression was found. In the group of dysplastic naevi, 9 significant and highly significant correlations between GADD genes and mismatch repair genes were found. In the group of fibromatous naevi, MLH1 correlated significantly with GADD45 and highly significant with GADD34 expression. Different correlations in naevi groups investigated show the different functional connections between the genes of DNA repair.

Prognostic relevance of histologic grading, the cell cycle-associated antigen Ki-S1 and cell cycle regulators in malignant fibrous histiocytomas: a multivariate analysis

The main aim of this study was to compare the prognostic impact of different histologic grading systems, the expression of the cell cycle-associated antigen DNA-topoisomerase-II-alpha (Ki-S1) and the expression of cell cycle regulators in malignant fibrous histiocytomas (MFH) using multivariate analyses. Paraffin-embedded tissue of 161 cases of MFH were studied immunohistochemically for the expression of the proliferation marker Ki-S1, cell cycle regulators (p53, MDM2, waf-1, pRb, p16) and the oncoprotein EGFR. The percentage of immunolabelled tumor cells (index) was assessed. The histologic grade was determined by the two-level grading systems of Costa, Tsujimoto and Pezzi, by the three-level grading systems of Coindre and Van Unnik and by the grading system presented here. Univariate analyses using the LOG rank test showed that all of the applied grading systems produce highly significant differences in survival between the grades of malignancy. Multivariate analyses with COX regression demonstrated that only the grading system presented here, based on the parameters necroses, mitoses and cellularity, had independent prognostic relevance. Moreover, the inclusion of the proposed grading system, the Ki-S1-index and a prognostic index primarily based on the expression of cell cycle regulators into the COX regression was suited for predicting survival in MFH. The grading system presented shows considerable advantages over the grading systems compared in this study for use in the routine pathology of MFH. The prognostic power of the proposed grading system can be enhanced by the combined study of cell cycle regulators and Ki-S1.

How can one explain aneuploidy status in fibromatous and lipomatous naevus cell naevus?

34 lightly fibromatous, 23 heavily fibromatous, 5 lipomatous and 10 naevus cell naevi were stained with Feulgen kit in order to evaluate their ploidy status with CAS 200 image analyzer. 26/34 lightly fibromatous, 18/23 heavily fibromatous, and 5/5 lipomatous naevi were either suspicious for aneuploidy (Auer III) or clearly aneuploid (Auer IV). In contrast all 10/10 naevus cell naevi were euploid. Proliferation (S-phase) was not increased in naevi fibromatously and lipomatously changed. The mechanisms leading to aneuploidy are discussed.

The role of nm23 in melanoma progression and its prognostic significance

The nm23 monoclonal antibody directed to specific antigen was applied for investigation of 29 benign naevi, 59 melanomas of different Clark level and locations, 4 lymph node and 28 organ metastases, using quantitative immunohistochemistry. The reduced expression of nm23 protein was associated with the tumor progression. A statistically significant difference (p = 0.0014) was found in nm23 protein expression between naevi and malignant melanomas. Additionally, a reduced protein level in metastases was found. A strong correlation was found between nm23 expression and survival of patients as well as the presence of metastasis (p = 0.0003).

Grading system for breast cancer

As recurrence rates in breast cancer depend significantly on degree of malignancy (6-9) and mitotic rates as part of the grading system are difficult to assess in exact manner, we widened the grading system by evaluation of the proliferative compartment to get more information about proliferation activity as an important factor for tumor-progression (15, 16). This additional analysis can be used as a control factor for the correctness of the evaluation of mitotic activity. We practice this procedure at present as a "working formulation". New antibodies are in preparation which allow to exclude the highly variable G1-Phase. Further precision and control of degree of malignancy can be achieved by photometric analysis of S-Phase, 5c exceeding rate and state of ploidy according to Auer scheme.

Analysis of the DNA content in Bowen's disease

The aim of this study was to evaluate the DNA content in Bowen's disease in comparison to healthy epidermis applying image cytophotometry. The material investigated was derived from 50 patients with Bowen's disease and 10 patients with healthy skin. For comparison of both groups the Kruskal-Wallis test was applied. Slides were stained with Feulgen and were evaluated with CAS-200 image analyzer. Only 7/50 morbus Bowen cases represented euploid histogram. The others 43/50 were either conspicious to be aneuploid (29/50) or clearly aneuploid (14/50). In contrast, all normal epidermis (10/10) were clearly euploid. Morbus Bowen cases demonstrated significantly higher 5c exceeding rate (p=0.0012) and significantly more cells in the S-phase (p=0.017). High aneuploidy rate and increased proliferative activity in morbus Bowen cases support the classification of these lesion as carcinoma in situ.

Differential expression of growth arrest, DNA damage genes and tumour suppressor gene p53 in naevi and malignant melanomas

Twenty nine benign naevi and 59 melanomas of different Clark level and locations were stained immunohistochemically for the presence of p53 and 3 members of Growth Arrest. DNA Damage inducible family: GADD 34, GADD 45 and GADD 153. All naevi were p53 negative and highly GADD positive. Differences in the expression of all 3 GADD proteins between naevi and melanomas were highly significant (p = 0.0001). The expression of p53 increased and the expression of GADD proteins decreased with the Clark level of melanoma thickness. The survival time of patients correlated negatively with p53 positivity and positively with GADD 45 and 153 expression. Prognostic significance for GADD 34 was not found. Our conclusion is that GADD proteins play an important role in the malignant transformation of naevus to melanoma and GADD 45 and GADD 153 proteins can influence patient survival.

Defects of insulin and IGF-1 action at receptor and postreceptor level in a patient with type A syndrome of insulin resistance

The action of insulin and IGF-1 in comparison to non-diabetic controls was studied in cultured fibroblasts of a patient with an inherited syndrome of insulin resistance (Type A syndrome). Insulin binding was reduced due to decreased receptor affinity, but sequence analyses revealed no alterations of splicing or primary insulin receptor (IR) structure. Most likely due to the IR affinity defect analyses of signal transduction pathways showed an impairment of insulin action on glucose uptake, total RNA synthesis and phosphorylation as well as activity of MAP-kinase. In addition inducibility of c-fos mRNA level was strongly impaired by insulin and IGF-1, but comparable to controls by PDGF indicating a postreceptor defect. In conclusion, we provide evidence that genetic syndromes of insulin resistance can be associated with both, receptor and postreceptor defects.

Analysis of ploidy status in progression of head and neck cancers by DNA image cytometry

Eight cases of leukoplakia, 25 lingual cancers, 15 cancers of the floor of the oral cavity, 11 pharyngeal cancers and 14 lymph nodes with squamous cell cancer metastases were stained using the Feulgen method to evaluate the ploidy status and ploidy related parameters. All leukoplakias were euploid. Percentage of aneuploid cancers correlated with the grade of tumours. Significant differences between tumours with 3 different locations were not found. Metastatic carcinoma cells in lymph nodes had significantly more cells in S-phase as compared to primary tumours.

Prognostic relevance of Ki-67 antigen and c-myc oncoprotein in malignant fibrous histocytoma

47 cases of malignant fibrous histiocytoma were stained immunohistochemically for the presence of Ki-67 antigen and c-myc oncoprotein. Percentage of Ki-67 and c-myc positive cells correlated with each other and with grade of tumour, mitotic index, cellularity and survival time of patients, but not with the extent of necrosis. Differences of mean values of Ki-67 index between grade I and grade II tumours as well as between grade II and grade III tumours were highly statistically significant. All 3 parameters connected with c-myc expression (index, intensity and score) differed significantly between grade I and grade II tumours but not between grade II and grade III MFH. The possible differential role of Ki-67 antigen and c-myc oncoprotein for improvement of grading is discussed.

Antigen Ki-67 and c-myc oncogene as related to histoclinical parameters in pigmented skin lesions

121 cases of cutaneous melanomas, 82 lymph nodes with melanoma metastases and 62 naevi were stained immunohistochemically for presence of Ki-67 antigen and c-myc oncogene. A significant correlation between expression of investigated markers, and survival time as well as presence of metastases, in cutaneous melanomas was found (p < 0.05). The role of Ki-67 antigen for differential diagnosis between naevi and melanomas is also demonstrated.

P-53 positivity and high proliferative index: factors of bad prognosis in malignant fibrous histiocytomas

57 cases of malignant fibrous histiocytomas (MFH) were examined, immunohistochemically for the presence of p-53-tumour suppressor gene with monoclonal antibody DO-7 (Dako) and for the presence of Ki-67 antigen using monoclonal antibody MIB-1 (Dianova). The statistical relationship between the overexpression of p-53 and grading parameters (mitoses, cellularity, necrosis) and expression of Ki-67 antigen as well as survival time, was determined. The presence of p-53 antigen was found in 29.8% of grade II and grade III tumours, but not in MFH of grade I. The p-53 positive cases demonstrated a significantly higher mitotic index (p < 0.05), higher Ki-67 index (p < 0.05) and shorter survival time (p < 0.05) in comparison to p-53 negative cases. Differences concerning cellularity and extent of necrosis, between p-53 positive and p-53 negative tumours were not found (p > 0.05). The prognostic role of p-53 overexpression in MFH is discussed.