CT-guided high dose rate brachytherapy can induce multiple systemic proteins of proliferation and angiogenesis predicting outcome in HCC.

BACKGROUND AND PURPOSE: To determine the potential prognostic value of proliferation and angiogenesis plasma proteins following CT-guided high dose rate brachytherapy (HDR-BT) of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: For this prospective study, HDR-BT (1 × 15 Gy) was administered to 24 HCC patients. Plasma was obtained and analyzed using an Olink proteomics Target-96 immuno-oncology-panel that included multiple markers of angiogenesis and proliferation. Fold-change (FC) ratios were calculated by comparing baseline and 48 h post HDR-BT paired samples. Patients were classified as responders (n = 12) if they had no local progression within 6 months or systemic progression within 2 years. Non-responders (n = 12) had recurrence within 6 months and/or tumor progression or extrahepatic disease within 2 years. RESULTS: Proliferation marker EGF was significantly elevated in non-responders compared to responders (p = 0.0410) while FGF-2, HGF, and PlGF showed no significant differences. Angiogenesis markers Angiopoietin-1 and PDGF-B were likewise significantly elevated in non-responders compared to responders (p = 0.0171, p = 0.0462, respectively) while Angiopoietin-2, VEGF-A, and VEGFR-2 did not differ significantly. Kaplan-Meier analyses demonstrated significantly shorter time to systemic progression in patients with increased EGF and Angiopoietin-1 (p = 0.0185, both), but not in patients with one of the remaining proteins elevated (all p > 0.1). Pooled analysis for these 9 proteins showed significantly shorter time to systemic progression for FC ≥1.3 and ≥1.5 for at least 3 proteins elevated (p = 0.0415, p = 0.0193, respectively). CONCLUSION: Increased plasma levels of EGF and Angiopoietin-1 after HDR-BT for HCC are associated with poor response and may therefore function as predictive biomarkers of outcome.

Characteristics and quality assessment of online mentoring profile texts in academic medical mentoring.

BACKGROUND: Mentoring is important for a successful career in academic medicine. In online matching processes, profile texts are decisive for the mentor-selection. We aimed to qualitatively characterize mentoring-profile-texts, identify differences in form and content and thus elements that promote selection. METHODS: In a mixed method study first, quality of texts in 150 selected mentoring profiles was evaluated (10-point Likert scale; 1 = insufficient to 10 = very good). Second, based on a thematic and content analysis approach of profile texts, categories and subcategories were defined. We compared the presence of the assigned categories between the 25% highest ranked profiles with the 25% lowest ranked ones. Finally, additional predefined categories (hot topics) were labelled on the selected texts and their impact on student evaluation was statistically examined. RESULTS: Students rated the quality of texts with a mean of 5.89 ± 1.45. 5 main thematic categories, 21 categories and a total of 74 subcategories were identified. Ten subcategories were significantly associated with high- and four with low-rated profiles. The presence of three or more hot topics in texts significantly correlated with a positive evaluation. CONCLUSION: The introduced classification system helps to understand how mentoring profile texts are composed and which aspects are important for choosing a suited mentor.

Fibroblast growth factors induce hepatic tumorigenesis post radiofrequency ablation.

Image-guided radiofrequency ablation (RFA) is used to treat focal tumors in the liver and other organs. Despite potential advantages over surgery, hepatic RFA can promote local and distant tumor growth by activating pro-tumorigenic growth factor and cytokines. Thus, strategies to identify and suppress pro-oncogenic effects of RFA are urgently required to further improve the therapeutic effect. Here, the proliferative effect of plasma of Hepatocellular carcinoma or colorectal carcinoma patients 90 min post-RFA was tested on HCC cell lines, demonstrating significant cellular proliferation compared to baseline plasma. Multiplex ELISA screening demonstrated increased plasma pro-tumorigenic growth factors and cytokines including the FGF protein family which uniquely and selectively activated HepG2. Primary mouse and immortalized human hepatocytes were then subjected to moderate hyperthermia in-vitro, mimicking thermal stress induced during ablation in the peri-ablational normal tissue. Resultant culture medium induced proliferation of multiple cancer cell lines. Subsequent non-biased protein array revealed that these hepatocytes subjected to moderate hyperthermia also excrete a similar wide spectrum of growth factors. Recombinant FGF-2 activated multiple cell lines. FGFR inhibitor significantly reduced liver tumor load post-RFA in MDR2-KO inflammation-induced HCC mouse model. Thus, Liver RFA can induce tumorigenesis via the FGF signaling pathway, and its inhibition suppresses HCC development.

Circulating miR-21 as a prognostic biomarker in HCC treated by CT-guided high-dose rate brachytherapy.

BACKGROUND AND AIMS: Prognostic biomarkers identifying patients with early tumor progression after local ablative therapy remain an unmet clinical need. The aim of this study was to investigate circulating miR-21 and miR-210 levels as prognostic biomarkers of HCC treated by CT-guided high-dose rate brachytherapy (HDR-BT). MATERIALS AND METHODS: 24 consecutive HCC patients (BCLC A and B) treated with CT-guided HDR-BT (1 × 15 Gy) were included in this prospective IRB-approved study. RT-PCR was performed to quantify miR-21 and miR-210 levels in blood samples acquired prior to and 2 d after HDR-BT. Follow-up imaging (contrast-enhanced liver MRI and whole-body CT) was performed in 3 months follow-up intervals. Therapy response was assessed with patients classified as either responders or non-responders (12 each). Responders were defined as having no local or diffuse systemic progression within 6 months and no diffuse systemic progression exceeding 3 nodules/nodule diameter > 3 cm from 6 months to 2 years. Non-responders had recurrence within 6 months and/or tumor progression with > 3 nodules or individual lesion diameter > 3 cm or extrahepatic disease within two years, respectively. Biostatistics included parametric and non-parametric testing (Mann-Whitney-U-test), as well as Kaplan-Meier curve construction. RESULTS: The responder group demonstrated significantly decreasing miR-21 values 2 d post therapy compared to non-responders (median miR-21 2-ΔΔCт: responders 0.73 [IQR 0.34], non-responders 1.53 [IQR 1.48]; p = 0.0102). miR-210 did not show any significant difference between responders and non-responders (median miR-210 2-ΔΔCт: responders 0.74 [IQR 0.45], non-responders 0.99 [IQR 1.13]; p = 0.8399). Kaplan-Meier curves demonstrated significantly shorter time to systemic progression for increased miR-21 (p = 0.0095) but not miR-210 (p = 0.7412), with events accumulating > 1 year post therapy in non-responders (median time to systemic progression 397 days). CONCLUSION: Increasing circulating miR-21 levels are associated with poor response and shorter time to systemic progression in HDR-BT-treated HCC. This proof-of-concept study provides a basis for further investigation of miR-21 as a prognostic biomarker and potential stratifier in future clinical trials of interventional oncology therapies. TRIAL REGISTRATION: In this monocentric clinical study, we analyzed prospectively acquired data of 24 patients from the "ESTIMATE" patient cohort (Studiennummer: DRKS00010587, Deutsches Register Klinischer Studien). Ethical approval was provided by the ethics committee "Ethikkommission bei der LMU München" (reference number "17-346") on June 20, 2017 and August 26, 2020.

Post-therapeutic microRNA-146a in liquid biopsies may determine prognosis in metastatic gastrointestinal cancer patients receiving 90Y-radioembolization.

PURPOSE: The role of microRNA-146a (miR-146a) in defining the tumor immune microenvironment (TIME) is well established. The aim of this study was to evaluate circulating miR-146a as an early prognostic marker of 90Y-radioembolization (90Y-RE) in metastatic liver cancer and to assess the correlation between circulating miR-146a and TIME cellular composition in distant, yet untreated metastases. METHODS: Twenty-one patients with bilobar liver lesions from gastro-intestinal cancer underwent lobar 90Y-RE. Biopsy of contralateral lobe abscopal tumors was acquired at the onset of a second treatment session at a median of 21 days after initial RE, immediately prior to ablation therapy of the contralateral lobe tumor. miR-146a was measured by RT-qPCR in plasma collected 24 h before (T1) and 48 h after (T2) initial unilobar 90Y-RE. The level of miR-146a was correlated with the infiltration of CD4 + , CD8 + , FoxP3 T cells, CD163 + M2 macrophages and immune-exhausted T cells in the abscopal tumor tissue acquired before the second treatment session. RESULTS: Plasma samples collected at T2 showed a higher concentration of miR-146a with respect to T1 in 43% of the patients (p = 0.002). In these patients, tumors revealed a pro-tumorigenic immune composition with enrichment of Tim3 + immune exhausted cells (p = 0.021), in combination with a higher infiltration of CD163 + M2 macrophages and a lower infiltration of CD8 + T cells. Patients with a higher level of miR-146a after 90Y-RE showed a trend to shorter OS (p = 0.055). CONCLUSION: miR-146a may represent a novel prognostic biomarker for 90Y-radioembolization in metastatic liver cancer.

Radiofrequency Ablation-Induced Tumor Growth Is Suppressed by MicroRNA-21 Inhibition in Murine Models of Intrahepatic Colorectal Carcinoma.

PURPOSE: To investigate the role of microRNA-21 (miR21) in radiofrequency (RF) ablation-induced tumor growth and whether miR21 inhibition suppresses tumorigenesis. MATERIAL AND METHODS: Standardized liver RF ablation was applied to 35 C57/BL6 mice. miR21 and target proteins pSTAT3, PDCD4, and PTEN were assayed 3 hours, 24 hours, and 3 days after ablation. Next, 53 Balb/c and 44 C57BL/6 mice received Antago-miR21 or scrambled Antago-nc control, followed by intrasplenic injection of 10,000 CT26 or MC38 colorectal tumor cells, respectively. Hepatic RF ablation or sham ablation was performed 24 hours later. Metastases were quantified and tumor microvascular density (MVD) and cellular proliferation were assessed at 14 or 21 days after the procedures, respectively. RESULTS: RF ablation significantly increased miR21 levels in plasma and hepatic tissue at 3 and 24 hours as well as target proteins at 3 days after ablation (P < .05, all comparisons). RF ablation nearly doubled tumor growth (CT26, 2.0 SD ± 1.0 fold change [fc]; MC38, 1.9 SD ± 0.9 fc) and increased MVD (CT26, 1.9 SD ± 1.0 fc; MC38, 1.5 ± 0.5 fc) and cellular proliferation (CT26, 1.7 SD ± 0.7 fc; MC38, 1.4 SD ± 0.5 fc) compared with sham ablation (P < .05, all comparisons). RF ablation-induced tumor growth was suppressed when Antago-miR21 was administered (CT26, 1.0 SD ± 0.7 fc; MC38, 0.9 SD ± 0.4 fc) (P < .01, both comparisons). Likewise, Antago-miR21 decreased MVD (CT26, 1.0 SD ± 0.3 fc; MC38, 1.0 SD ± 0.2 fc) and cellular proliferation (CT26, 0.9 SD ± 0.3 fc; MC38, 0.8 SD ± 0.3 fc) compared with baseline (P < .05, all comparisons). CONCLUSIONS: RF ablation upregulates protumorigenic miR21, which subsequently influences downstream tumor-promoting protein pathways. This effect can potentially be suppressed by specific inhibition of miR21, rendering this microRNA a pivotal and targetable driver of tumorigenesis after hepatic thermal ablation.

Prediction of Protumorigenic Effects after Image-Guided Radiofrequency Ablation of Hepatocellular Carcinoma Using Biomarkers.

PURPOSE: To perform radiofrequency (RF) ablation of hepatocellular carcinoma (HCC) and to assess serological and histopathological markers of tumorigenesis in distant untreated tumors to determine whether these were associated with unfavorable outcomes such as early relapse and increased biological aggressiveness. MATERIALS AND METHODS: The study cohort comprised 13 patients from a prospective single-arm study. All patients underwent 2 ablation sessions of multifocal HCC nodules 14 days apart. Core biopsy samples of untreated tumors were acquired at baseline and at the time of the second ablation session. Samples were stained immunohistochemically with Ki-67 (proliferation) and CD34 (microvasculature). Blood plasma was obtained at baseline and 2 days after the initial ablation session and analyzed for hepatocyte growth factor (HGF), vascular endothelial growth factor C, and angiopoietin-2 using an enzyme-linked immunosorbent assay. The clinical follow-up period ranged from 7 to 25 months. Patients were stratified as responders (complete remission or limited and delayed recurrence at >6 months; n = 6) or nonresponders (any recurrence within 6 months or >3 new tumors or any new tumor of >3 cm thereafter; n = 7). RESULTS: In 3 of 7 nonresponders, the Ki-67 index markedly increased in untreated tumors, whereas Ki-67 was stable in all responders. Microvascular density strongly increased in a single nonresponder only. HGF and angiopoietin-2 increased by >30% in 3 of 7 and 4 of 7 nonresponders, respectively, whereas they were stable or decreased in responders. Overall, ≥2 biomarkers were elevated in 6 of 7 (85.7%) nonresponders, whereas 4 of 6 responders demonstrated no increased biomarker and 2 patients demonstrated increase in 1 biomarker only (P = .002). CONCLUSIONS: RF ablation of HCC can produce protumorigenic factors that induce effects in distant untreated tumors. These may potentially function as biomarkers of clinical outcome.

Elevated circulating Hsp70 levels are correlative for malignancies in different mammalian species.

Circulating Hsp70 levels were determined in feline and porcine cohorts using two different ELISA systems. These comparative animal models of larger organisms often reflect diseases, and especially malignant tumors, better than conventional rodent models. It is therefore essential to investigate the biology and utility of tumor biomarkers in animals such as cats and pigs. In this study, levels of free Hsp70 in the blood of cats with spontaneously occurring tumors were detected using a commercial Hsp70 ELISA (R&D Systems). Sub-analysis of different tumor groups revealed that animals with tumors of epithelial origin presented with significantly elevated circulating Hsp70 concentrations. In addition to free Hsp70 levels measured with the R&D Systems Hsp70 ELISA, levels of exosomal Hsp70 were determined using the compHsp70 ELISA in pigs. Both ELISA systems detected significantly elevated Hsp70 levels (R&D Systems: median 24.9 ng/mL; compHsp70: median 44.2 ng/mL) in the blood of a cohort of APC1311/+ pigs diagnosed with high-grade adenoma polyps, and the R&D Systems Hsp70 ELISA detected also elevated Hsp70 levels in animals with low-grade polyps. In contrast, in flTP53R167H pigs, suffering from malignant osteosarcoma, the compHsp70 ELISA (median 674.32 ng/mL), but not the R&D Systems Hsp70 ELISA (median 4.78 ng/mL), determined significantly elevated Hsp70 concentrations, indicating that in tumor-bearing animals, the dominant form of Hsp70 is of exosomal origin. Our data suggest that both ELISA systems are suitable for detecting free circulating Hsp70 levels in pigs with high-grade adenoma, but only the compHsp70 ELISA can measure elevated, tumor-derived exosomal Hsp70 levels in tumor-bearing animals.

Early monocyte response following local ablation in hepatocellular carcinoma.

Local ablative therapies are established treatment modalities in the treatment of early- and intermediate-stage hepatocellular carcinoma (HCC). Systemic effects of local ablation on circulating immune cells may contribute to patients' response. Depending on their activation, myeloid cells are able to trigger HCC progression as well as to support anti-tumor immunity. Certain priming of monocytes may already occur while still in the circulation. By using flow cytometry, we analyzed peripheral blood monocyte cell populations from a prospective clinical trial cohort of 21 HCC patients following interstitial brachytherapy (IBT) or radiofrequency ablation (RFA) and investigated alterations in the composition of monocyte subpopulations and monocytic myeloid-derived suppressor cells (mMDSCs) as well as receptors involved in orchestrating monocyte function. We discovered that mMDSC levels increased following both IBT and RFA in virtually all patients. Furthermore, we identified varying alterations in the level of monocyte subpopulations following radiation compared to RFA. (A) Liquid biopsy liquid biopsy of circulating monocytes in the future may provide information on the inflammatory response towards local ablation as part of an orchestrated immune response.

Thinking outside the box: students positive about visionary elective curricula in medical school.

Objective: Space for personality development as well as for the development of critical, creative and interdisciplinary thinking is rarely found in medical curricula in Germany. To be prepared for the challenges of modern medicine, future physicians need a visionary mindset. The aim of this study is to determine the need for teaching such content among medical students in the context of visionary elective curricula and to examine these with regard to the desired topics and organizational structure. Methods: This is a cross-sectional study with 236 medical students from all semesters of the Ludwig-Maximilians-University Munich. The survey consists of 50 questions and includes single choice, multiple choice, matrix questions, open-ended questions and Likert scales. Responses were examined using descriptive statistics and compared parametrically in sub-aspects. Results: Three-quarters of respondents would like to see curricular content on interdisciplinary interfaces with other disciplines. A suitable framework for this is seen by 87% of the respondents in a visionary elective curriculum. Students would like to see a broad range of specific content such as global health, politics, business, and computer science. The majority of respondents would like to see 1 unit of instruction per week and would participate in an appropriate program. Such an offering would promote creative (53.6%), critical (63.7%), and interdisciplinary thinking (69.0%) and train to become better physicians (87%). Conclusion: Participants in this study are positive toward the introduction of visionary content in medical school. Faculties should build visionary elective curricula according to the graduate profile requirements of the new NKLM 2.0 to make medical education sustainable.

Hsp70 in Liquid Biopsies-A Tumor-Specific Biomarker for Detection and Response Monitoring in Cancer.

In contrast to normal cells, tumor cells of multiple entities overexpress the Heat shock protein 70 (Hsp70) not only in the cytosol, but also present it on their plasma membrane in a tumor-specific manner. Furthermore, membrane Hsp70-positive tumor cells actively release Hsp70 in small extracellular vesicles with biophysical characteristics of exosomes. Due to conformational changes of Hsp70 in a lipid environment, most commercially available antibodies fail to detect membrane-bound and vesicular Hsp70. To fill this gap and to assess the role of vesicular Hsp70 in circulation as a potential tumor biomarker, we established the novel complete (comp)Hsp70 sandwich ELISA, using two monoclonal antibodies (mAbs), that is able to recognize both free and lipid-associated Hsp70 on the cell surface of viable tumor cells and on small extracellular vesicles. The epitopes of the mAbs cmHsp70.1 (aa 451-461) and cmHsp70.2 (aa 614-623) that are conserved among different species reside in the substrate-binding domain of Hsp70 with measured affinities of 0.42 nM and 0.44 nM, respectively. Validation of the compHsp70 ELISA revealed a high intra- and inter-assay precision, linearity in a concentration range of 1.56 to 25 ng/mL, high recovery rates of spiked liposomal Hsp70 (>84%), comparable values between human serum and plasma samples and no interference by food intake or age of the donors. Hsp70 concentrations in the circulation of patients with glioblastoma, squamous cell or adeno non-small cell lung carcinoma (NSCLC) at diagnosis were significantly higher than those of healthy donors. Hsp70 concentrations dropped concomitantly with a decrease in viable tumor mass upon irradiation of patients with approximately 20 Gy (range 18-22.5 Gy) and after completion of radiotherapy (60-70 Gy). In summary, the compHsp70 ELISA presented herein provides a sensitive and reliable tool for measuring free and vesicular Hsp70 in liquid biopsies of tumor patients, levels of which can be used as a tumor-specific biomarker, for risk assessment (i.e., differentiation of grade III vs. IV adeno NSCLC) and monitoring of therapeutic outcomes.

7Hsp70 serum levels in pet dogs-a potential diagnostic biomarker for spontaneous round cell tumors.

The concentration of circulating heat shock protein 70 (Hsp70) was measured in liquid biopsies of canine tumor patients as a potential biomarker. Compared with rodent tumor models, spontaneously occurring tumors in pet dogs reflect the clinical situation of human patients better, as dogs cohabitate with their owners in the same environment, reach a much older age than rodents, can provide blood samples much more frequently, and receive up-to-date medical care and, similar to humans, their tumors show a high genetic heterogeneity. Due to the species-specific sequence homology of human and canine Hsp70, two human enzyme-linked immunosorbent assay (ELISA) systems (R&D and lipHsp70) were used to measure canine Hsp70 concentrations in serum and plasma. In general, higher Hsp70 concentrations were found in serum compared with plasma samples of dogs, and the lipHsp70 ELISA detected higher peak concentrations of Hsp70 in a broader range than the R&D ELISA. Compared with a tumor-free control group, serum Hsp70 concentrations were higher in tumor-bearing dogs, irrespective of breed, age, body weight, and gender. A sub-classification of the different tumors according to their cytological characteristics revealed significantly elevated Hsp70 serum concentrations in dogs with round cell tumors (p < 0.01), a heterogeneous group of malignancies with hematopoietic origin such as mast cells, plasma cells, lymphocytes, histiocytes, and melanomas. Future studies with larger patient cohorts and well-defined tumor sizes are necessary to elucidate the role of serum Hsp70 as a biomarker for tumor detection and monitoring of outcome in pet animals.