Predictors of BRAF mutation in melanocytic nevi: analysis across regions with different UV radiation exposure.

BACKGROUND: BRAF mutations have been implicated in initiating promutagenic cellular melanocytic proliferation mostly based on homogeneous Western-based cohorts. Data addressing the possible interaction between exposure to different solar ultraviolet radiation (UVR) magnitudes and BRAF mutation rate (BMR) in melanocytic nevi are limited. DESIGN: Extended BRAF testing for 9 mutations in 225 melanocytic nevus (MN) cases derived from 211 patients from 4 different UVR regions: Lebanon (n = 95; 110 kJ · m(-2) · yr), Syria (n = 23; 93.5 kJ · m(-2) · yr), Kingdom of Saudi Arabia (n = 70; 139 kJ · m(-2) · yr), and Pakistan (n = 37; 118 kJ · m(-2) · yr) was performed. Data collected included age, gender, anatomic location, and lesion size. Histological parameters recorded were MN type (junctional, compound, intradermal, classical blue, cellular blue, compound and intradermal spitz, and congenital) solar elastosis grade, and nevus pigmentation degree. Cumulative 21-year erythemally effective UV averages were derived from The National Center for Atmospheric Research. RESULTS: BRAF mutation status was obtained in 210 cases (6.7% failed polymerase chain reaction). Overall, BMR was 62.4% (131/210) with V600E mutation accounting for 98.5% of cases. Discordant mutation status was found in 2 of 10 patients with multiple nevi. BMR differed significantly, yet nonsystematically, among UVR regions; the highest was detected in nevi coming from Syria (18/23 cases, 78%), followed by Pakistan (21/30 cases, 70%), Kingdom of Saudi Arabia (47/70 cases, 67%), and Lebanon (45/87 cases, 52%). Mutation rates varied significantly across MN type (P < 0.001); the highest rate was recorded in the intradermal nevus type (33/39 cases, 84.6%), followed by the compound (26/32 cases, 81.2%) and congenital (60/74 cases 81.0%) nevi. Stratified by anatomic location, nevi occurring on the face (61/82, 74%) and trunk (58/78, 74%) had more frequent BMRs compared with those occurring on the upper (7/26, 27%) and lower extremities (5/24, 21%, P < 0.001). Severe pigmentation was less frequent in BRAF mutation-positive nevi [5/131 (4%) vs. 34/79 (43%); P < 0.001]. Multivariate independent predictors of BRAF mutation in MN were age [odds ratio (95% confidence interval ) = 1.43 (1.13-1.74) per 10 years; P = 0.004], anatomic location [P = 0.043 overall], and nevus type [P < 0.001 overall]. UVR region was not an independent predictor of BRAF mutation. CONCLUSIONS: Increased BRAF mutation with age along with the lack of a UVR magnitude-BRAF mutation association suggests that duration of exposure rather than UVR exposure dose is the more likely link to acquiring the mutation.

The human impact of commercial delivery cycling injuries: a pilot retrospective cohort study.

BACKGROUND: Commercial delivery cyclists represent a uniquely vulnerable and poorly understood road user. The primary aim of this study was to pilot whether cycling injuries could be categorised as either commercial or non-commercial using documentation entered into routine hospital medical records, in order to determine the feasibility of conducting a large cohort study of commercial cycling injuries in the future. A secondary aim was to determine which key demographic, incident and injury characteristics were associated with commercial versus non-commercial cycling injuries in emergency. METHODS: Pilot retrospective cohort study of adults presenting to an acute public hospital emergency department between May 2019 and April 2020 after sustaining a cycling-related injury. Multinomial logistic regression was used to examine the demographic, incident and injury characteristics associated with commercial compared to non-commercial cycling. RESULTS: Of the 368 people presenting to the emergency department with a cycling-related injury, we were able to categorise 43 (11.7%) as commercial delivery cyclists, 153 (41.6%) as non-commercial cyclists and the working status of 172 (46.7%) was unable to be confirmed. Both commercial and unconfirmed cyclists were more likely to be younger than non-commercial cyclists. Compared to non-commercial cyclists, commercial cyclists were 11 times more likely to speak a language other than English (AOR 11.3; 95% CI 4.07-31.30; p<0.001), less likely to be injured from non-collision incidents than vehicle collisions (AOR 0.36; 95% CI 0.15-0.91; p=0.030) and were over 13 times more likely to present to the emergency department between 8.00pm and 12.00am compared to the early morning hours (12.00 to 8.00am) (AOR 13.43; 95% CI 2.20-82.10; p=0.005). CONCLUSIONS: The growth of commercial cycling, particularly through online food delivery services, has raised concern regarding commercial cyclist safety. Improvements in the recording of cycling injury commercial status is required to enable ongoing surveillance of commercial cyclist injuries and establish the extent and risk factors associated with commercial cycling.

A Multi-Analyte Approach for Improved Sensitivity of Liquid Biopsies in Prostate Cancer.

Novel androgen receptor (AR) signaling inhibitors have improved the treatment of castration-resistant prostate cancer (CRPC). Nonetheless, the effect of these drugs is often time-limited and eventually most patients become resistant due to various AR alterations. Although liquid biopsy approaches are powerful tools for early detection of such therapy resistances, most assays investigate only a single resistance mechanism. In combination with the typically low abundance of circulating biomarkers, liquid biopsy assays are therefore informative only in a subset of patients. In this pilot study, we aimed to increase overall sensitivity for tumor-related information by combining three liquid biopsy approaches into a multi-analyte approach. In a cohort of 19 CRPC patients, we (1) enumerated and characterized circulating tumor cells (CTCs) by mRNA-based in situ padlock probe analysis, (2) used RT-qPCR to detect cancer-associated transcripts (e.g., AR and AR-splice variant 7) in lysed whole blood, and (3) conducted shallow whole-genome plasma sequencing to detect AR amplification. Although 44-53% of patient samples were informative for each assay, a combination of all three approaches led to improved diagnostic sensitivity, providing tumor-related information in 89% of patients. Additionally, distinct resistance mechanisms co-occurred in two patients, further reinforcing the implementation of multi-analyte liquid biopsy approaches.

Regulation of the E2F-associated phosphoprotein promoter by GC-box binding proteins.

The E2F-associated phosphoprotein (EAPP) is a ubiquitous nuclear protein that interacts with the activating members of the E2F family of transcription factors and increases the activity of several cell-cycle regulated promoters in an E2F-dependent manner. Our previous studies also showed that EAPP levels are elevated in most transformed human cells. To examine the molecular basis of this increase of EAPP we isolated and studied the nucleotide sequence at the 5' end of the EAPP gene. In silico analysis revealed a TATA-less promoter with several putative binding sites for transcription factors, the most probable ones being Sp1, Sp3 and Egr-1. We could confirm the binding of these factors in vitro by electrophoretic mobility shift assays, supershift experiments and competition assays. Additionally we could validate the binding in vivo by chromatin-immunoprecipitation assays. To analyse the function of these transcription factors in the expression of EAPP, we performed reporter-assays with the promoter and truncations thereof. We found that Sp1 and Egr-1 stimulate the EAPP promoter, whereas Sp3 acts as a repressor that could even overcome the positive effect of the activators. Increasing the amounts of Sp3 also caused a strong reduction of EAPP, but the overexpression of Sp1 or Egr-1 resulted in only marginally higher EAPP levels. Our results suggest that the elevated EAPP levels in transformed cells can be caused by reduced Sp3 activity, but higher Sp1 activity might also play a role.

EAPP, a novel E2F binding protein that modulates E2F-dependent transcription.

E2F transcription factors play an essential role in cell proliferation and apoptosis and their activity is frequently deregulated in human cancers. In a yeast two-hybrid screen we identified a novel E2F-binding protein. Due to its strong phosphorylation we named it EAPP (e2F-associated phosphoprotein). EAPP is localized in the nucleus and interacts with E2F-1, E2F-2, and E2F-3, but not with E2F-4. Examination of a number of human cell lines revealed that EAPP levels are elevated in most transformed cells. Moreover, EAPP mRNA was detected in all investigated human tissues in varying amounts. EAPP is present throughout the cell cycle but disappears during mitosis. In transfection assays with reporters controlled by either an artificial E2F-dependent promoter or the murine thymidine kinase promoter, EAPP increased the activation caused by E2F-1 but not by E2F-4. Surprisingly, the promoter of the p14(ARF) gene, which was also activated by E2F-1, became repressed by EAPP. Overexpression of EAPP in U2OS cells resulted in a significant increase of cells in S-phase, whereas RNAi-mediated knock down of EAPP reduced the fraction of cells in S-phase. Taken together, these data suggest that EAPP modulates E2F-regulated transcription, stimulates proliferation, and may be involved in the malignant transformation of cells.

EGFR Mutational Profiling in Non-Small Cell Lung Cancer: The Clinical Performance of a Sensitive Reverse-Hybridization Assay.

In patients with non-small cell lung cancer (NSCLC), epidermal growth factor receptor (EGFR) mutations have been associated with the tumor response to targeted therapy with EGFR tyrosine kinase inhibitors. Although labor intensive and not very sensitive (ie, an analytical sensitivity of 20%), direct sequencing is widely used for mutation detection. This study aimed at evaluating the potential of a test strip-based reverse-hybridization assay (EGFR StripAssay), designed for the simultaneous detection of 16 mutations in exons 18 to 21 of the EGFR gene, to sensitively identify EGFR mutation in DNA from NSCLC tissue samples. Formalin-fixed paraffin-embedded (FFPE) DNA samples from 59 patients with a histologically confirmed primary NSCLC tumor were used to compare the performance of the EGFR StripAssay against that of the Sanger sequencing. The EGFR StripAssay analysis identified 7 (11.8%) of 59 FFPE samples to carry an EGFR mutation, of which 4 (57.1%) and 3 (42.8%) samples were positive for exon 19 and 21 mutations, respectively. Of note, no sample was identified with EGFR exon 18 or 20 mutation. All mutations were confirmed by DNA sequencing. Using 50 ng of template DNA, the EGFR StripAssay demonstrated a detection limit of 1% mutant sequence in a background of normal DNA. The EGFR StripAssay is a fast and robust platform for the sensitive detection of EGFR mutation in FFPE DNA. Therefore, this assay could be considered as an alternative protocol to Sanger sequencing for EGFR mutation testing on limited-quantity samples.

BRAF and NRAS Mutations in Papillary Thyroid Carcinoma and Concordance in BRAF Mutations Between Primary and Corresponding Lymph Node Metastases.

Concordance between mutations in the primary papillary thyroid carcinoma (PTC) and the paired x lymph node metastasis may elucidate the potential role of molecular targeted therapy in advanced stages. BRAF and NRAS mutations in primary PTC (n = 253) with corresponding metastatic lymph node (n = 46) were analyzed utilizing StripAssays (ViennaLab Diagnostics). Statistical analysis was performed using (SPSS, Inc.), version 24.0 with a p-value of <0.05, and concordance via kappa agreement. BRAF mutation frequency in conventional PTC (cPTC): 56.8%, papillary thyroid microcarcinoma (PTMC): 36.5%, PTMC-FV: 2.7% and PTC-FV: 4.1%. NRAS mutation frequency in PTC-FV: 28.6%, PTMC: 28.6%, PTMC-FV: 23.8%, and cPTC: 19.0%. BRAF mutation correlation with older age in cPTC (42.6 versus 33.6) years (p < 0.001) was the only significant clinicopathologic parameter. BRAF mutations were concordant in the primary and its corresponding lymph node deposits in PTC with a kappa of 0.77 (p-value < 0.0001). BRAF mutations are predominant in cPTC and PTMC while NRAS mutations in PTC-FV. BRAF mutation is conserved in metastatic lymph node deposits, thus BRAF is an early mutational pathogenetic driver. Therefore, targeted therapy is potential in recurrent and advanced stage disease.

Comparison of neuroendocrine differentiation and KRAS/NRAS/BRAF/PIK3CA/TP53 mutation status in primary and metastatic colorectal cancer.

Neuroendocrine differentiation of tumor tissue has been recognized as an important prerequisite for new targeted therapies. To evaluate the suitability of colorectal cancer (CRC) tissue for these treatment approaches and to find a possible link to pretherapeutic conditions of other targeted strategies, we compared neuroendocrine differentiation and KRAS/NRAS/BRAF/PIK3CA/TP53 mutational status in primary and metastatic CRC. Immunohistochemical expression analysis of neuroendocrine markers chromogranin A and synaptophysin was performed on archival CRC tissue, comprising 116 primary tumors, 258 lymph node metastases and 72 distant metastases from 115 patients. All CRC samples but 30 distant metastases were subjected to mutation analysis of KRAS, NRAS, BRAF, PIK3CA, and TP53. Neuroendocrine marker expression was found significantly less frequently in lymph node metastases compared to primary tumors and distant metastases (20%, 31%, 28%, respectively, P = 0.044). KRAS mutation rates increased significantly from primary tumors to lymph node metastases and distant metastases within the neuroendocrine negative CRC group (44%, 53%, 64%, respectively, P = 0.042). Neuroendocrine differentiation was significantly less concordant than KRAS/NRAS/BRAF/PIK3CA/TP53 mutational status in primary tumor/lymph node metastases pairs (65% versus 88%-99%; P < 0.0001) and primary tumor/distant metastases pairs (64% versus 83%-100%; P = 0.027 and P < 0.0001, respectively). According to these data, therapeutic targeting of neuroendocrine tumor cells can be considered only for a subset of CRC patients and biopsies from the metastatic site should be used to guide therapy. A possible importance of lacking neuroendocrine differentiation for progression of KRAS mutant CRC should be further investigated.

Proximal human FOXP3 promoter transactivated by NF-kappaB and negatively controlled by feedback loop and SP3.

Forkhead box protein 3 (Foxp3) is indispensable for the development of CD4(+)CD25(+) regulatory T cells (Tregs). Here we analyzed three prominent evolutionary conserved regions (ECRs) upstream of the transcription start site of the human FOXP3 gene. We show that ECR2 and ECR3 fragments derived from positions -1.3 to -2.0 kb and -5.0 to -6.0 kb, respectively, display basal transcriptional activity. Reporter constructs derived from ECR1, located between -0.6 and +0.23 kb and thus the most proximal ECR in respect of transcription initiation, remained almost inactive. However, ECR1 was transactivated by the NF-kappaB subunit p65 in HEK 293 cells. In Jurkat and primary T cells, in addition to p65, a second stimulus delivered by either T-cell receptor stimulation or addition of PMA was needed. Co-expression of I kappaB alpha inhibited p65-mediated FOXP3 proximal promoter transactivation, and the NF-kappaB inhibitor curcumin reduced Foxp3 neoexpression in IL-2/CD3/CD28/TGF-beta stimulated PBMCs. Moreover, proximal FOXP3 promoter transactivation was inhibited by Foxp3 and the SP transcription factor family member SP3. Thus, the human proximal FOXP3 promoter is controlled by activation through the TCR involving PKC and the NF-kappaB subunit p65 and by inhibition through a negative feedback loop and SP3.