151 research outputs found
Intracellular localization of Crimean-Congo Hemorrhagic Fever (CCHF) virus glycoproteins
BACKGROUND: Crimean-Congo Hemorrhagic Fever virus (CCHFV), a member of the genus Nairovirus, family Bunyaviridae, is a tick-borne pathogen causing severe disease in humans. To better understand the CCHFV life cycle and explore potential intervention strategies, we studied the biosynthesis and intracellular targeting of the glycoproteins, which are encoded by the M genome segment. RESULTS: Following determination of the complete genome sequence of the CCHFV reference strain IbAr10200, we generated expression plasmids for the individual expression of the glycoproteins G(N )and G(C), using CMV- and chicken β-actin-driven promoters. The cellular localization of recombinantly expressed CCHFV glycoproteins was compared to authentic glycoproteins expressed during virus infection using indirect immunofluorescence assays, subcellular fractionation/western blot assays and confocal microscopy. To further elucidate potential intracellular targeting/retention signals of the two glycoproteins, GFP-fusion proteins containing different parts of the CCHFV glycoprotein were analyzed for their intracellular targeting. The N-terminal glycoprotein G(N )localized to the Golgi complex, a process mediated by retention/targeting signal(s) in the cytoplasmic domain and ectodomain of this protein. In contrast, the C-terminal glycoprotein G(C )remained in the endoplasmic reticulum but could be rescued into the Golgi complex by co-expression of G(N). CONCLUSION: The data are consistent with the intracellular targeting of most bunyavirus glycoproteins and support the general model for assembly and budding of bunyavirus particles in the Golgi compartment
Association between physical activity, grip strength and sedentary behaviour with incidence of malignant melanoma: results from the UK Biobank
Background
Physical activity has been positively related to malignant melanoma. However, that association may be confounded by ultraviolet radiation (UV), a variable closely related to both outdoor physical activity and malignant melanoma. We examined physical activity, grip strength and sedentary behaviour in relation to risk of malignant melanoma, accounting for relevant confounders using data from a prospective cohort study.
Methods
In 350,512 UK Biobank participants aged 38–73 years at baseline, physical activity was assessed with a modified version of the International Physical Activity Questionnaire Short Form, grip strength was measured with a hand dynamometer, and sedentary behaviour was recorded with three specific questions. Multivariable hazard ratios (HR) and corresponding 95% confidence intervals (CI) were estimated using Cox proportional hazards regression.
Results
During 7 years of follow-up, 1239 incident malignant melanoma diagnoses were recorded. Physical activity and sedentary behaviour were unrelated to malignant melanoma (HRs 1.01 (95% CI 0.95–1.07) and 1.04 (95% CI 0.97–1.12), respectively), and the initially positive association with grip strength in the basic model (HR 1.23, 95% CI 1.08–1.40) was attenuated after full adjustment (HR 1.10, 95% CI 0.96–1.26).
Conclusion
Physical activity, grip strength and sedentary behaviour are not associated with malignant melanoma risk
Degree of Actinic Elastosis Is a Surrogate of Exposure to Chronic Ultraviolet Radiation and Correlates More Strongly with Cutaneous Squamous Cell Carcinoma than Basal Cell Carcinoma
(1) Background: Keratinocyte cancer (KC) is associated with exposure to ultraviolet (UV) radiation. However, data are controversial as to whether chronic UV exposure or high intermittent UV exposure are key drivers of carcinogenesis in cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC). Prolonged sun exposure of the skin causes photo-aging, which is associated with actinic elastosis, a condition characterized by the degeneration of elastin in the upper dermis, which is assessable via conventional histology. In this study, we aimed to compare the degree of actinic elastosis in different types of KC with regard to various patient characteristics. (2) Methods: We defined a semiquantitative score for the degree of actinic elastosis ranging from 0 = none to 3 = total loss of elastic fibers (basophilic degeneration). The extent was measured histometrically by two independent dermatohistopathologists in the immediate vicinity of 353 KC. The scores were merged and matched with tumor types (cSCC and BCC with subtypes), and clinical variables such as body site, sex and age. (3) Results: As expected, the degree of actinic elastosis correlated with age. However, it was significantly higher in cSCC compared to BCC irrespective of age, sex, body site and tumor subtypes. (4): Conclusions: Lifetime sun exposure may be estimated via routine histology using this scoring technique for actinic elastosis as a surrogate marker. cSCCs are more strongly associated with chronic UV exposure than BCCs, even in sun-exposed localizations such as the face
Immunometabolic Markers in a Small Patient Cohort Undergoing Immunotherapy
Although the discovery of immune checkpoints was hailed as a major breakthrough in can cer therapy, generating a sufficient response to immunotherapy is still limited. Thus, the objective of
this exploratory, hypothesis-generating study was to identify potentially novel peripheral biomarkers
and discuss the possible predictive relevance of combining scarcely investigated metabolic and hor monal markers with immune subsets. Sixteen markers that differed significantly between responders
and non-responders were identified. In a further step, the correlation with progression-free survival
(PFS) and false discovery correction (Benjamini and Hochberg) revealed potential predictive roles
for the immune subset absolute lymphocyte count (rs = 0.51; p = 0.0224 *), absolute basophil count
(rs = 0.43; p = 0.04 *), PD-1+ monocytes (rs = −0.49; p = 0.04 *), hemoglobin (rs = 0.44; p = 0.04 *),
metabolic markers LDL (rs = 0.53; p = 0.0224 *), free androgen index (rs = 0.57; p = 0.0224 *) and CRP
(rs = −0.46; p = 0.0352 *). The absolute lymphocyte count, LDL and free androgen index were the
most significant individual markers, and combining the immune subsets with the metabolic markers
into a biomarker ratio enhanced correlation with PFS (rs = −0.74; p ≤ 0.0001 ****). In summary, in
addition to well-established markers, we identified PD-1+ monocytes and the free androgen index as
potentially novel peripheral markers in the context of immunotherapy. Furthermore, the combination
of immune subsets with metabolic and hormonal markers may have the potential to enhance the
power of future predictive scores and should, therefore, be investigated further in larger trials
Potential Use of Gluconate in Cancer Therapy
We have recently discovered that cancer cells take up extracellular citrate through plasma membrane citrate transporter (pmCiC) and advantageously use citrate for their metabolism. Citrate uptake can be blocked with gluconate and this results in decreased tumor growth and altered metabolic characteristics of tumor tissue. Interestingly, gluconate, considered to be physiologically neutral, is incidentally used in medicine as a cation carrier, but not as a therapeutically active substance. In this review we discuss the results of our recent research with available literature and suggest that gluconate may be useful in the treatment of cancer
Head and neck melanoma: outcome and predictors in a population-based cohort study
Background
To evaluate predictive clinico-pathological characteristics on outcome in head and neck melanoma (HNM) in a population-based study with particular emphasis on the prognostic effect of sentinel lymph node biopsy (SLNB), Charlson comorbidity index (CCI) and distinct tumor localisations.
Methods
Here we primarily describe a retrospective multicenter population-based cohort study with 402 patients having undergone resection with curative intent of HNM between 2010 and 2017. SLNB was used in the diagnosis of 79 HNM patients. Outcome was analyzed, focusing on SLNB, CCI as well as tumor localisation. Overall survival (OAS) und recurrence free survival (RFS) was examined by uni- and multivariate analysis.
Results
Histopathologically verified lymph node metastasis according to SLNB was associated with impaired RFS in HNM patients (p = 0.004). Especially in higher tumor stages, the sole implementation of SLNB improved survival significantly in the present cohort (p = 0.042). With most of the HNM being located in the face, melanoma of the scalp and neck could be linked to deteriorated patient’s outcome in uni- as well as multivariate analysis (p = 0.021, p = 0.004).
Conclusions
SLNB is a useful tool in predicting development of distant metastasis after HNM resection with curative intent. Especially in higher tumor stages, performing a SLNB ameliorated survival of HNM patients. Additionally, CCI as well as a distinct tumor localisations in HNM were identified as important risk factors in our population-based cohort study
Discontinuation of BRAF/MEK-Directed Targeted Therapy after Complete Remission of Metastatic Melanoma—A Retrospective Multicenter ADOReg Study
The advent of BRAF/MEK inhibitors (BRAFi/MEKi) has significantly improved progressionfree (PFS) and overall survival (OS) for patients with advanced BRAF-V600-mutant melanoma.
Long-term survivors have been identified particularly among patients with a complete response
(CR) to BRAF/MEK-directed targeted therapy (TT). However, it remains unclear which patients who
achieved a CR maintain a durable response and whether treatment cessation might be a safe option
in these patients. Therefore, this study investigated the impact of treatment cessation on the clinical
course of patients with a CR upon BRAF/MEK-directed-TT. We retrospectively selected patients with
BRAF-V600-mutant advanced non-resectable melanoma who had been treated with BRAFi ± MEKi
therapy and achieved a CR upon treatment out of the multicentric skin cancer registry ADOReg.
Data on baseline patient characteristics, duration of TT, treatment cessation, tumor progression (TP)
and response to second-line treatments were collected and analyzed. Of 461 patients who received
BRAF/MEK-directed TT 37 achieved a CR. TP after initial CR was observed in 22 patients (60%)
mainly affecting patients who discontinued TT (n = 22/26), whereas all patients with ongoing TT
(n = 11) maintained their CR. Accordingly, patients who discontinued TT had a higher risk of TP
compared to patients with ongoing treatment (p < 0.001). However, our data also show that patients
who received TT for more than 16 months and who discontinued TT for other reasons than TP or
toxicity did not have a shorter PFS compared to patients with ongoing treatment. Response rates
to second-line treatment being initiated in 21 patients, varied between 27% for immune-checkpoint
inhibitors (ICI) and 60% for BRAFi/MEKi rechallenge. In summary, we identified a considerable
number of patients who achieved a CR upon BRAF/MEK-directed TT in this contemporary realworld cohort of patients with BRAF-V600-mutant melanoma. Sustained PFS was not restricted to
ongoing TT but was also found in patients who discontinued TT
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