Of the seven in absentia homologue (SIAH) family, three members have been identified in the human genome. In contrast to the E3 ubiquitin ligase encoding SIAH1 and SIAH2, little is known on the regulation and function of SIAH3 in tumorigenesis. In this study, we reveal that SIAH3 is frequently epigenetically silenced in different cancer entities, including cutaneous melanoma, lung adenocarcinoma and head and neck cancer. Low SIAH3 levels correlate with an impaired survival of cancer patients. Additionally, induced expression of SIAH3 reduces cell proliferation and induces cell death. Functionally, SIAH3 negatively affects cellular metabolism by shifting cells form aerobic oxidative phosphorylation to glycolysis. SIAH3 is localized in the mitochondrion and interacts with proteins involved in mitochondrial ribosome biogenesis and translation. We also report that SIAH3 interacts with ubiquitin ligases, including SIAH1 or SIAH2, and is degraded by them. These results suggest that SIAH3 acts as an epigenetically controlled tumor suppressor by regulating cellular metabolism through the inhibition of oxidative phosphorylation.
PDF file - 98K, Table 1. Toxicity of the intention to treat (ITT) population, classified and graded according to CTC 2.0 (http://ctep.cancer.gov/reporting/ctc.html). Data represent the worst CTC grade experienced by each patient. Table 2. Morphological and molecular tumor characteristics as analyzed in the per protocol (PP) population, for details see Patients and Methods. PDGFRB, platelet-derived growth factor receptor beta; EGFR, epidermal growth factor receptor; IR, insulin receptor; NA, not applicable.
ZusammenfassungMetabolische Anpassungsprozesse, vermittelt durch sog. Hypoxie-induzierbare Faktoren und deren Zielgene, spielen in zahlreichen Malignomen eine wichtige Rolle. Rasch wachsende Tumoren können ihre Stoffwechselvorgänge an eine auftretende Hypoxie anpassen. So werden beispielsweise nach der Aktivierung des „Hypoxia inducible-factors-1α“ Modifikationen am Glukosestoffwechsel, der intrazellulären pH-Regulation oder der Angiogenese initiiert. In dieser immunhistochemischen Pilotstudie analysierten wir primär kutane Melanome mit positivem und negativem Schildwächterlymphknotenstatus im Hinblick auf mögliche Unterschiede ihrer metabolischen Signatur. Hierbei konnten wir unter anderem zeigen, dass die Expression von Glukosetransporter‑1 (GLUT-1) sowohl in allen Melanomen ohne Subgruppenanalyse, als auch in der Subgruppe mit negativem Schildwächterlymphknoten positiv mit der Tumordicke sowie dem Vorliegen einer Ulzeration korrelierte. Zudem korrelierte bei Melanomen mit positivem Schildwächterlymphknoten die Expression von vaskulärem endothelialem Wachstumsfaktor (VEGF) positiv mit dem Vorliegen einer Ulzeration.
Metabolic reprogramming mediated by hypoxia-inducible factors play a crucial role in many human cancers. HIF-1α is activated under hypoxic conditions and is considered a key regulator of oxygen homoeostasis during tumor proliferation under hypoxia. Aim of this research was to analyze the immunohistochemical expression of HIF-1α, VEGF-A, Glut-1, MCT4, and CAIX in atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS). 21 paraffin-embedded AFX and 22 PDS were analysed by immunohistochemistry, namely HIF-1α, VEGF-A (referred to as VEGF throughout the manuscript), Glut-1, MCT4, and CAIX. To quantify the protein expression, we considered the percentage of positive tumor cells (0: 0%, 1: up to 1%, 2: 2-10%, 3: 11-50%, 4: >50%) in relation to the staining intensity (0: negative, 1: low, 2: medium, 3: strong). HIF-1α expression (mean ± SD) in AFX (9.33±2.92) was significantly stronger than that in PDS (5.90±4.38; P= 0.007), whereas the expression of VEGF, Glut-1, MCT4, and CAIX did not show differences between AFX and PDS. When comparing all tumors without subgroup stratification, the expression of HIF-1α (P= 0.044) and MCT4 (P= 0.036) was significantly stronger in ulcerated tumors than in tumors without ulceration. Our findings provide the first evidence that HIF-1α-induced metabolic reprogramming may contribute to the pathogenesis of AFX and PDS. HIF-1α expression seems to be higher in AFX than in PDS, and ulcerated tumors show higher expression levels of HIF-1α and MCT4 irrespective of the diagnosis.
Background: Metabolic reprogramming and altered gene expression mediated by hypoxia-inducible factors play crucial roles during tumour growth and progression. Nevertheless, studies analysing the expression of hypoxia-inducible factor-1a and its downstream targets in Merkel cell carcinoma (MCC) are lacking but are warranted to shed more light on MCC pathogenesis and to potentially provide new therapeutic options. Objectives: To analyse the immunohistochemical expression of hypoxia-inducible factor-1 alpha (HIF-1 alpha), vascular endothelial growth factor-A (referred to as VEGF throughout the manuscript), VEGF receptor-2 (VEGFR-2), VEGF receptor-3 (VEGFR-3), glucose transporter-1 (Glut-1), monocarboxylate transporter 4 (MCT4) and carbonic anhydrase IX (CAIX) in primary cutaneous MCC. Methods: The 16 paraffin-embedded primary cutaneous MCCs (Merkel cell polyomavirus (McPyV) positive/negative: 11/5) were analysed by immunohistochemistry, namely HIF-1 alpha, VEGF, VEGFR-2 (KDR), VEGFR-3 (FLT4), Glut-1, MCT4 and CAIX. An established quantification score (QS) was applied to quantitate the protein expression by considering the percentage of positive tumour cells (0: 0%; 1: up to 1%; 2: 2-10%; 3: 11-50%; 4: >50%) in relation to the staining intensity (0: negative; 1: low; 2: medium; 3: strong). Results: HIF-1 alpha was expressed in all MCCs and predominantly found at the invading edges of tumour margins. The HIF-1 alpha downstream factors Glut-1, MCT4 and CAIX were expressed in 13 of 16 MCC (81%), 14 of 16 MCC (88%) and 16 of 16 MCC (100%), respectively. Interestingly, VEGF and VEGFR-2 were not expressed in tumour cells, whereas VEGFR-3 was expressed in all MCCs. HIF-1 alpha was expressed significantly stronger in McPyV(+) tumours (QS: 10.36 +/- 2.41) than in McPyV(-) tumours (QS: 5.40 +/- 1.34; P = 0.002). Similarly, VEGFR-3 was also expressed significantly stronger in McPyV+ tumours (QS: 10.00 +/- 2.52) than in McPyV- tumours (QS: 5.40 +/- 3.43, P = 0.019). Conclusions: Our data provide first evidence for a role of HIF-1 alpha in induced metabolic reprogramming contributing to MCC pathogenesis. The metabolic signatures of McPyV(+) and McPyV(-) tumours seem to show relevant differences.
This study analysed the expression of vascular endothelial growth factor-A (VEGF), VEGFR-2, and VEGFR-3 in primary cutaneous melanomas with positive and negative sentinel node status (SLN) (a total of 58 specimens divided into 2 groups of 29 for each status). The specimens were collected from the pathological archive of the department of Dermatology, Venereology and Allergology of the University Medical Center Heidelberg. A quantification score was developed for protein expression, by considering the percentage of positive melanoma cells (0: 0%, 1: up to 1%, 2: 2-10%, 3: 11-50%, and 4: > 50%) in relation to the intensity of staining (0: negative, 1: low, 2: medium, 3: strong). Tumoural VEGFR-3 expression (mean ± standard deviation) in SLN+ tumours (9.62 ± 3.09) was significantly stronger than in SLN- tumours (6.13 ± 3.87; p < 0.001). A binary logistic regression model proved VEGFR-3 expression and tumour thickness to be significant independent predictors of SLN. These data provide evidence that VEGFR-3 expression may play a critical role in the pathogenesis of malignant melanoma and that its investigation may help to improve the selection of patients with primary cutaneous melanoma for sentinel node biopsy.
To shed more light on the pathogenesis of sebaceous carcinoma, we analysed the expression of proteins related to angiogenesis in 18 ocular and 22 extraocular sebaceous carcinomas using a broad panel of immunohistochemical markers. To quantify the expression of D2-40, vascular endothelial growth factor, vascular endothelial growth factor receptor-2 and -3, we calculated a quantification score by considering the percentage of positive tumour cells (0=0%, 1=up to 1%, 2=2-10%, 3=11-50%, and 4=>50%) in relation to the staining intensity (0=negative, 1=low, 2=medium, and 3=strong). Additionally, lymphatic microvessel density in the D2-40 stained sections was counted. Vascular endothelial growth factor receptor-3 (quantification score 9.42 ± 2.94) was significantly more strongly expressed than vascular endothelial growth factor receptor-2 (quantification score 2.15 ± 2.42, p < 0.001). Furthermore, epidermal vascular endothelial growth factor expression was negatively correlated with the intratumoural lymphatic vessel density, and the ratio of small lymphatics to large lymphatics was much higher in intratumoural tissue than in paratumoural tissue and in intraindividual control tissue, suggesting a lymphangiogenetic potential of sebaceous carcinoma.
In Germany, the reported syphilis prevalence has increased continuously since 2010, with a total of 6834 syphilis cases being reported in 2015. The largest increase of reported syphilis occurred in men who have sex with men (MSM). The antibiotic agent of choice for treatment of syphilis is still penicillin. There are no penicillin-resistant Treponema pallidum strains. Alternatives are ceftriaxone and doxycycline. In Germany, azithromycin is not approved for treatment of syphilis; however, therapy failures are increasingly reported. Bacterial vaginosis is accompanied by vaginal discharge. The vaginal secretion exhibits an increased pH value higher than 4.5. Clinical symptoms are pruritus, burning, and the characteristic amine odor. The probability for bacterial vaginosis is highest in women with higher numbers of sexual partners, unmarried women, early first sexual intercourse, in commercial female sex workers, and those women who regularly apply vaginal douches. The main pathogen of bacterial vaginosis is Gardnerella vaginalis. For oral therapy metronidazole is given, alternatively clindamycin; the latter should be applied additionally as topical agent. Trichomoniasis is considered as the nonviral sexually transmitted infection with the highest prevalence worldwide. Other than direct microscopic detection of the protozoa (trophozoites) in vaginal secretion or urine, PCR has been approved as the diagnostic method with the highest sensitivity. Oral metronidazole represents the therapy of choice in trichomoniasis.
Approximately 1 million people are infected per day worldwide by one or more sexually transmitted infections (STI) as estimated by the World Health Organization (WHO). Gonorrhoea represents an almost exclusively sexually transmitted infection, which predominantly affects mucous membranes of the genitourinary tract. Extragenital localization of infections is also possible, e. g. in the anorectal region. Currently, only syphilis and human immunodeficiency virus (HIV) are notifiable diseases according to the Infection Protection Act in Germany. In Saxony, an extended registration ordinance according to the German Infection Protection Act is in force, which means that besides syphilis the laboratory detection of Neisseria gonorrhoeae, Chlamydia trachomatis and genital mycoplasms are also notifiable infections. In particular, beginning in 2009 in Saxony a spectacular increase of registered infections due to N. gonorrhoeae was observed and in 2015 altogether 824 infections due to N. gonorrhoeae were reported. Alarming is the increase in resistance of N. gonorrhoeae against penicillin, doxycycline, ciprofloxacin and recently also against azithromycin and third generation cephalosporins. The so-called superbug of N. gonorrhoeae, which originated in Japan with multidrug resistance against most of the currently available oral antibiotics, has now arrived in Europe. Intramuscular or intravenous injection of ceftriaxone plus oral azithromycin, each given as single dose is the standard therapy for gonorrhoea.
Chlamydia trachomatis is the most common pathogen of sexually transmitted bacterial infections worldwide. Every year in Germany approximately 300,000 new infections are to be expected. Chlamydia infections occur nearly exclusively in the postpubertal period. The peak age group is 15-25 years. The infection usually runs an asymptomatic course and the diagnosis is made by nucleic acid amplification techniques (NAAT) often after chlamydial screening or if complications occur. For treatment of chlamydial infections oral doxycycline 100 mg twice daily over 7 days is initially used or alternatively oral azithromycin 1.5 g as a single dose is recommended. The sexual partner should also be investigated and treated. Genital Mycoplasma infections are caused by Ureaplasma urealyticum (pathogen of urethritis and vaginitis), Ureaplasma parvum (mostly saprophytic and rarely a cause of urethritis) and Mycoplasma hominis (facultative pathogenic). Mycoplasma genitalium represents a relatively new sexually transmitted Mycoplasma species. Doxycycline is effective in Ureaplasma infections or alternatively clarithromycin and azithromycin. Doxycycline can be ineffective in Mycoplasma hominis infections and an alternative is clindamycin. Non-gonococcal and non-chlamydial urethritis due to Mycoplasma genitalium can now be diagnosed by molecular biological techniques using PCR and should be treated by azithromycin.
Chlamydia trachomatis ist der weltweit am häufigsten sexuell übertragene bakterielle Infektionserreger. Jährlich rechnet man in Deutschland mit etwa 300.000 Neuinfektionen. Die Erkrankungen treten fast ausschließlich postpubertär auf. Der Altersgipfel liegt in der Altersgruppe 15 bis 25 Jahre. Da die Infektion überwiegend asymptomatisch verläuft, wird die Diagnose mittels Nukleinsäureamplifikationstechniken (NAT) oft nur durch ein Screening oder erst bei Auftreten einer Komplikation gestellt. Zur Behandlung kommt an erster Stelle Doxycyclin 2‑mal 100 mg p. o. über 7 Tage zum Einsatz. Alternativ wird Azithromycin 1,5 g p. o. als 1‑malige Gabe empfohlen. Partneruntersuchung und -therapie sind zu beachten. Genitale Mykoplasmen-Infektionen werden durch Ureaplasma urealyticum (Urethritis- und Vaginitiserreger), Ureaplasma parvum (meist saprophytär, selten Urethritiserreger) und Mycoplasma hominis (fakultativ pathogen) verursacht. Eine relativ neue, durch sexuellen Kontakt übertragene Mykoplasmen-Art ist Mycoplasma genitalium. Doxycyclin ist wirksam bei Ureaplasma-Infektionen, alternativ Clarithromycin oder Azithromycin. Doxycyclin kann bei Mycoplasma-hominis-Infektionen versagen, eine Alternative stellt Clindamycin dar. Die Urethritis durch Mycoplasma genitalium sollte heute molekularbiologisch mittels Polymerasekettenreaktion diagnostiziert und mit Azithromycin behandelt werden.
Epigenetic inactivation of tumor-related genes is an important characteristic in the pathology of human cancers, including melanomagenesis. We analyzed the epigenetic inactivation of Claudin 11 (CLDN11) in malignant melanoma (MM) of the skin, including six melanoma cell lines, 39 primary melanoma, 41 metastases of MM and 52 nevus cell nevi (NCN). CLDN11 promoter hypermethylation was found in 19 out of 39 (49%) of the primary MM and in 21 out of 41 (51%) of the MM metastases, but only in eight out of 52 (15%) of NCN (p = 0.001 and p = 0.0003, respectively). Moreover, a significant increase in the methylation level of CLDN11 from primary melanomas to MM metastases was revealed (p = 0.003). Methylation of CLDN11 was significantly more frequent in skin metastases (79%) compared to brain metastases (31%; p = 0.007). CLDN11 methylation was also found in five out of six MM cell lines (83%) and its promoter hypermethylation correlated with a reduced expression. Treatment of MM cell lines with a DNA methylation inhibitor reactivated CLDN11 transcription by its promoter demethylation. In summary, CLDN11 proved to be an epigenetically inactivated tumor related gene in melanomagenesis, and analysis of CLDN11 methylation level represents a potential tool for assisting in the discrimination between malignant melanoma and nevus cell nevi.
Abstract Purpose: Dermatofibrosarcoma protuberans (DFSP) is a rare cutaneous tumor. COL1A1–PDGFB gene fusion is frequent in DFSP, rendering tumor cell proliferation and survival dependent on PDGFRβ (platelet-derived growth factor receptor β) signaling. This trial investigated imatinib as neoadjuvant treatment of DFSP, including long-term follow-up. Experimental Design: The primary endpoint of this multicenter phase II trial was response; secondary endpoints were safety, tumor relapse, and response biomarkers. Patients with advanced primary or locally recurrent DFSP and measurable disease by RECIST (response evaluation criteria in solid tumors) were eligible and received imatinib 600 mg/d until definitive surgery with histopathologic proof of tumor-free margins. Results: Sixteen patients received imatinib, and 14 patients were evaluable for all endpoints. Median treatment duration was 3.1 months; median tumor shrinkage was 31.5%. Best overall response was 7.1% complete response (CR), 50.0% partial response (PR), 35.7% stable disease, and 7.1% progressive disease (PD). Toxicity was moderate with 25.0% grade 3 and 4 events. During a median follow-up of 6.4 years, one patient developed secondary resistance to imatinib but responded to second-line sunitinib. This patient also presented local recurrence, distant metastasis, and death from DFSP. Exploratory analysis showed that response to imatinib was associated with decreased tumor cellularity and formation of strong hyalinic fibrosis. Weak PDGFRB phosphorylation and pigmented-type DFSP were associated with nonresponse. Additional to PDGFRB, the kinases EGFR and insulin receptor were found activated in a high percentage of DFSPs. Conclusion: The neoadjuvant use of imatinib 600 mg/d in DFSP is efficacious and well tolerated. Long-term follow-up results do not definitely support smaller surgical margins after successful imatinib pretreatment, and presume that secondary resistance to imatinib might promote accelerated disease progression. Clin Cancer Res; 20(2); 499–510. ©2013 AACR.
Malignant melanoma is a highly-aggressive type of malignancy with considerable metastatic potential and frequent resistance to cytotoxic agents. BRAF mutant protein was recently recognized as therapeutic target in metastatic melanoma. We present a newly-developed U-BRAF(V600) approach - a universal pyrosequencing-based assay for mutation detection within activation segment in exon 15 of human braf. We identified 5 different BRAF mutations in a single assay analyzing 75 different formalin-fixed paraffin-embedded (FFPE) samples of cutaneous melanoma metastases from 29 patients. We found BRAF mutations in 21 of 29 metastases. All mutant variants were quantitatively detectable by the newly-developed U-BRAF(V600) assay. These results were confirmed by ultra-deep-sequencing validation ((~)60,000-fold coverage). In contrast to all other BRAF state detection methods, the U-BRAF(V600) assay is capable of automated quantitative identification of at least 36 previously-published BRAF mutations. Under the precaution of a minimum of 3% mutated cells in front of a background of wild type cells, U-BRAFV600 assay design completely excludes false wild-type results. The corresponding algorithm for classification of BRAF-mutated variants is provided. The single-reaction assay and data analysis automation makes our approach suitable for the assessment of large clinical sample sizes. Therefore, we suggest U-BRAF(V600) assay as a most powerful sequencing-based diagnostic tool to automatically identify BRAF state as a prerequisite to targeted therapy.
A 71-year-old woman presented to our outpatient clinic with a new mass growing in her umbilicus. The solid and ulcerated tumor was of red-violet color and had a size of approximately 2 cm (Fig. 1a). In addition, the patient showed signs of ascites with a clearly bloated abdomen. Histopathological examination of the biopsy revealed a completely ulcerated epidermis with an underlying dermal infiltration of pleomorphic tumor cells with focal development of lumina (Fig. 1b). The lesion was diagnosed as a metastatic manifestation of a carcinoma of unknown origin. Immunohistochemically, carcinoma cells showed a high expression of CA125 and CK7. The patient was referred to the Department of Gynecology for further examination and diagnosed with metastatic ovarian carcinoma at an inoperable stage.
Merkel cell carcinoma (MCC) is one of the most aggressive cancers of the skin. RASSFs are a family of tumor suppressors that are frequently inactivated by promoter hypermethylation in various cancers. We studied CpG island promoter hypermethylation in MCC of RASSF2, RASSF5A, RASSF5C and RASSF10 by combined bisulfite restriction analysis (COBRA) in MCC samples and control tissue. We found RASSF2 to be methylated in three out of 43 (7%), RASSF5A in 17 out of 39 (44%, but also 43% in normal tissue), RASSF5C in two out of 26 (8%) and RASSF10 in 19 out of 84 (23%) of the cancer samples. No correlation between the methylation status of the analyzed RASSFs or between RASSF methylation and MCC characteristics (primary versus metastatic, Merkel cell polyoma virus infection, age, sex) was found. Our results show that RASSF2, RASSF5C and RASSF10 are aberrantly hypermethylated in MCC to a varying degree and this might contribute to Merkel cell carcinogenesis.