Early Marker Of Response Research Articles

The chicken chorioallantoic membrane as a low-cost, high-throughput model for cancer imaging

Mouse models are invaluable tools for radiotracer development and validation. They are, however, expensive, low throughput, and are constrained by animal welfare considerations. Here, we assessed the chicken chorioallantoic membrane (CAM) as an alternative to mice for preclinical cancer imaging studies. NCI-H460 FLuc cells grown in Matrigel on the CAM formed vascularized tumors of reproducible size without compromising embryo viability. By designing a simple method for vessel cannulation it was possible to perform dynamic PET imaging in ovo, producing high tumor-to-background signal for both 18F-2-fluoro-2-deoxy-D-glucose (18F-FDG) and (4S)-4-(3-18F-fluoropropyl)-L-glutamate (18F-FSPG). The pattern of 18F-FDG tumor uptake were similar in ovo and in vivo, although tumor-associated radioactivity was higher in the CAM-grown tumors over the 60 min imaging time course. Additionally, 18F-FSPG provided an early marker of both treatment response to external beam radiotherapy and target inhibition in ovo. Overall, the CAM provided a low-cost alternative to tumor xenograft mouse models which may broaden access to PET and SPECT imaging and have utility across multiple applications.

Early Peripheral Blood Blast Clearance As a Prognostic Marker for Early Treatment Response in Pediatric Acute Myeloid Leukemia

Background and Significance The cure rate of pediatric acute myeloid leukemia (AML) has improved significantly; however, relapses still occur in up to 30% of the total patient population in high-income countries (HICs), and in an even higher percentage of patients in low- and middle-income countries (LMICs). Early treatment response, cytogenetics and minimal residual disease (MRD) are well-known prognostic factors for treatment outcome; however, sophisticated techniques for identifying prognostic factors are often lacking in LMICs, and are sometimes unsuccessful in HICs. Early treatment response assessed by a bone marrow (BM) aspirate on day 15 or day 22 (D22) (depending on the applicable protocol) after initiation of chemotherapy is a known prognostic factor for outcome in patients with pediatric AML, but does not allow modifications of the first induction chemotherapy course (Creutzig 2014, Abrahamsson 2011, Kern 2003). In both pediatric acute lymphoid leukemia (ALL) and adult AML, early peripheral blood blast clearance (PBBC) is a known early indicator of treatment response (Manabe 2008, Arellano 2012), whereas to the best of our knowledge, this has not yet been reported in pediatric AML. In this study, we evaluated the significance of time to complete PBBC, and rate of PBBC after initiation of chemotherapy, in relation to disease status in BM D22, as measure of early treatment response that has prognostic significance. Study Design and Methods Pediatric patients with AML, aged 0-18 years, that were treated according to the NOPHO-DBH AML-2012 protocol were included. The first 5 days of induction therapy consisted of etoposide, followed by 7 days of low-dose cytarabine and mitoxantrone or liposomal daunorubicin. Peripheral blood (PB) was assessed by morphology at the time of diagnosis, daily in the first week, and thrice weekly until D22 or until occurrence of complete clearance of blasts. BM D22 was assessed by morphology and flow cytometry. A receiver operating characteristic (ROC) analysis was performed to evaluate the predictive power of days from starting chemotherapy to complete PBBC. The correlation between time to complete PBBC and BM D22 results was analyzed using a logistic regression model. Multivariable logistic regression models were applied for the association after adjusting for effects of other covariates. Rate of PBBC was defined as the percentage of the absolute PB blast count on the day of diagnosis that cleared with each day of therapy, on average, until D22 or the day of complete PBBC. Results In total, 319 patients were included, out of whom 241 were eligible for analysis, and 78 not eligible due to missing or incomplete data. Day 9 after initiation of chemotherapy was identified as the most discriminating cut-off point for predicting BM D22 response. Patients were categorized into early PBBC (≤9 days; n=159) and delayed PBBC (>9 days; n=82) groups. Early PBBC was associated with having <5% AML cells in BM D22 as assessed by both morphology (OR 3.11; P=0.005) and flow cytometry (OR 2.73; P=0.041). Early PBBC also showed a much lower likelihood of having >15% AML cells in BM D22 by morphology (OR 0.08; P=0.002). None of the early PBBC patients had >15% AML cells in BM D22 by flow cytometry. For 217 patients (selection due to missing data [n=24]), the rate of PBBC could be calculated, and a discriminative cut-off value of 11% was identified. Patients were categorized into high rate of PBBC (>11%; n=132) and low rate of PBBC (≤11%; n=85). High rate of PBBC was associated with having <5% AML cells in BM D22 by flow cytometry (OR 4.30; P=0.007) and negative MRD status (OR 2.02; P=0.004), while also showing a strong association with a lower likelihood of >15% AML cells in BM D22 (OR 0.11; P=0.007) by morphology. None of the high rate PBBC patients had >15% AML cells in BM D22 by flow cytometry. Conclusion Both early complete PBBC and rate of PBBC after initiation of chemotherapy holds promise as prognostic marker for clinical outcome in pediatric AML, as it correlates significantly with BM D22 response. These findings may offer an early and easily accessible prognostic factor, particularly beneficial for LMICs, as well as for patients with unsuccessful MRD analyses.

Researching an Early Marker for Immunotherapy Response

Researching an Early Marker for Immunotherapy Response

Early response markers predict survival after etoposide-based therapy of hemophagocytic lymphohistiocytosis

AbstractHemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome that is most commonly treated with etoposide and dexamethasone. This standard of care therapy has improved survival, but ∼15% of patients still die in the first months after diagnosis, and poor responses prompting salvage therapy are frequent. Thus, identifying patients at risk promptly is likely to improve outcomes. We conducted a multi-institutional, retrospective study of pediatric and young adults treated per HLH-94 or HLH-2004 from 2010 to 2019 to identify patients at risk for early mortality. Biweekly data during the first 100 days of treatment were analyzed using receiver operating curves to define optimal prognostic indicators and their thresholds. The primary end point was survival to bone marrow transplant (BMT) or ∼1 year if no BMT was pursued. Eighty-nine patients met the study inclusion criteria. Pre-BMT mortality was 13% (n = 12), and overall mortality was 27% (n = 24). Laboratory markers measured on day 7 of therapy more efficiently predicted outcomes than did either pretreatment or later assessments. The most potent day 7 unfavorable marker was improvement in soluble CD25 (sCD25) of less than 25% from pretherapy levels. Absolute sCD25 level, platelet count, absolute lymphocyte count, and blood urea nitrogen were also discriminatory markers (area under the curve ≥ 0.7). The presence of ≥3 of these unfavorable markers was strongly associated with pre-BMT mortality (accuracy, 0.93). Thus, serial monitoring of sCD25 and assessment of other early (day 7) response markers optimally predicts prognosis with etoposide-based therapy and may indicate the need for earlier use of alternative, response-adapted therapeutic strategies for HLH.

Monitoring of Vitiligo Patches Over Six Months to Validate Dermoscopic Findings of Lesional Stability.

Previously laid down criteria for lesional stability of vitiligo are inconsistent. Longitudinal data on correlation between dermoscopic features of vitiligo and disease activity is limited. To sequentially determine the dermoscopic features of vitiligo and to assess their association with the dynamic nature of the vitiligo patch. Sixty patients with 200 vitiligo patches fulfilling the inclusion criteria on medical therapy were subjected to sequential clinical and dermoscopic examination for 6 months. Baseline lesional photographs, dermoscopy and tracing of the patch was made and repeated at 6 months. The follow up tracing was superimposed onto the baseline tracing. Based on the increase or decrease in size, their outcomes were grouped as responsive, progressive and quiescent. Paired analysis of dermoscopic features was done between baseline, and their follow up after 6 months. Well defined border was associated with static nature of the vitiligo patch and ill-defined borders and trichrome pattern depicted its dynamic nature. Statistically significant increase in leukotrichia and satellite lesions amongst progressive patches and a decrease amongst responsive patches was observed. Pigment network changes were statistically significant for both responsive and progressive patches. Satellite lesions and micro-Koebner's phenomena was suggestive of progressive disease, while perifollicular pigmentation and perilesional hyperpigmentation was suggestive of re-pigmenting disease and proved to be an early marker for response to therapy. Repeated dermoscopic evaluation of lesions in a serial manner to assess disease activity helps understand their evolving nature and is a valuable tool in planning appropriate further treatment.

IP-10 and MIG are sensitive markers of early virological response to HIV-1 integrase inhibitors.

Interferon-inducible protein-10 (IP-10) and monokine induced by interferon-gamma (MIG) are chemokines recognized as inflammatory biomarkers during HIV-1 infection. We assessed their early and long-term dynamics after initiation of antiretroviral treatment (ART). Persons with HIV-1 (PWH) aged>18 years starting their first ART in 2015-2021 in a prospective cohort (n=73) were included. IP-10 and MIG plasma levels were quantified using a multiplexed bead-based assay. IP-10 and MIG plasma levels showed a significant and consistent reduction following ART (80% integrase inhibitor [INSTI]-based) initiation, starting at day 20 and maintained throughout the study period (48 months), paralleling the HIV-1 RNA decay and CD4+ count recovery (p<0·001). At baseline, PWH≥ 50 years, CDC stage C and CD4+ count<350cells/mm3 had higher levels of IP-10 (p=0·022, p=0·001 and p=0·002, respectively) and MIG (p<0·001, p=0·024 and p=0·069, respectively). All of them matched their counterparts several months following ART initiation. MIG levels showed a greater decrease at day 10 in those treated with INSTI (p=0·038). Low-level HIV-1 viremia did not impact MIG or IP-10 levels. Plasma IP-10 and MIG showed an early significant decline following ART initiation, with greater early declines in MIG levels in INSTI-based regimens. These findings suggest a strong impact of HIV-1 viremia on IP-10 and MIG levels.

Cardiac [99mTc]Tc-hydroxydiphosphonate uptake on bone scintigraphy in patients with hereditary transthyretin amyloidosis: an early follow-up marker?

PurposeThere is a need for early quantitative markers of potential treatment response in patients with hereditary transthyretin (ATTRv) amyloidosis to guide therapy. This study aims to evaluate changes in cardiac tracer uptake on bone scintigraphy in ATTRv amyloidosis patients on different treatments.MethodsIn this retrospective cohort study, outcomes of 20 patients treated with the transthyretin (TTR) gene silencer patisiran were compared to 12 patients treated with a TTR-stabilizer. Changes in NYHA class, cardiac biomarkers in serum, wall thickness, and diastolic parameters on echocardiography and NYHA class during treatment were evaluated.ResultsMedian heart/whole-body (H/WB) ratio on bone scintigraphy decreased from 4.84 [4.00 to 5.31] to 4.16 [3.66 to 4.81] (p < .001) in patients treated with patisiran for 29 [15–34] months. No changes in the other follow-up parameters were observed. In patients treated with a TTR-stabilizer for 24 [20 to 30] months, H/WB ratio increased from 4.46 [3.24 to 5.13] to 4.96 [ 3.39 to 5.80] (p = .010), and troponin T increased from 19.5 [9.3 to 34.0] ng/L to 20.0 [11.8 to 47.8] ng/L (p = .025). All other parameters did not change during treatment with a TTR-stabilizer.ConclusionA change in cardiac tracer uptake on bone scintigraphy may be an early marker of treatment-specific response or disease progression in ATTRv amyloidosis patients.

Particularities of arterial stiffness dynamics on the background of breast cancer chemotherapy

Modern breast cancer chemotherapy regimens (BC) consider individual patient parameters and ranges of cardiotoxic doses. However, clinicians often record clinical and laboratory-instrumental signs of cardio- and vasculotoxicity in patients, which emphasizes the high importance of searching for markers of early toxic response. To study the characteristics of the response of arterial stiffness on the background of anthracycline-containing chemotherapy to determine potential markers of vasculotoxicity in BC patients. 20 women with a BC were included. The patients received 4 cycles of chemotherapy in the doxorubicin + cyclophosphane (AC) regimen with an interval of 2-3 weeks, then they were injected with paclitaxel weekly for 12 injections, or docetaxel once every 3 weeks. All patients underwent TTE, arterial stiffness determination by the "gold standard" method and using volumetric sphygmography before the start of treatment, after the completion of the anthracycline component and after the end of taxanes. The average age of the patients was 45.5±5.31 years. After completing the course of anthracyclines, there was a significant increase in heart rate (from 65.6±9.3 to 73.3±10.1 beats/min.), a decrease in SBP (from 122.6±9.9 to 116.5±12.3 mmHg) and DBP (from 78.9±8.5 to 76.2±8.6 mmHg), a decrease in carotid femoral pulse wave velocity (cfPWV) (from 9.32±1.41 to 7.85±1.57 m/s), CAVI index on the left (from 6.78±0.81 to 6.5±0.88), the velocity of the cardio-ankle pulse wave on the right and left (from 6.7±0.6 to 6.5±0.7 m/s; from 7.0±0.6 to 6.3±0.8 m/sc, respectively). After the completion of the taxane, there was a tendency to increase these indicators, however, they remained significantly lower compared to the values before the start of treatment. A comparative analysis of arterial stiffness indicators at different stages of chemotherapy showed a more pronounced reaction of cfPWV, CAVI, cardio-ankle pulse wave to the administration of anthracyclines, which presumably may be associated with concomitant hemodynamic restructuring.

Prostate Tumor Regression during Radiation Therapy in Relation to Image Derived Estimates of Fibrosis Using Ultrashort Echo Time MRI

An inflammatory response due to radiation injury can lead to the activation of fibroblasts and their transformation into myofibroblasts that produce organized collagen layers. We term these organized collagen layers "acute fibrosis" (FA). Small animal imaging has shown that accumulation of fibrosis is accelerated at a higher radiation dose with later remodeling of type III collagen into densely packed type I collagen structures, which later transform into what we term "chronic fibrosis" (FC). In prostate cancer (PCa) patients treated with EBRT, we evaluated image derived FA (IDFA) and FC (IDFC) estimates using non-contrast and late gadolinium contrast enhanced (LGE) IR UTE, respectively. We hypothesized that fibrosis changes during RT are associated to tumor regression. Four PCa patients undergoing radiation and hormone suppression were included. 1.5T MR imaging was acquired at three time-points (TPs); pre-RT, on-RT (30-40 Gy), and post-RT (60-78 Gy). IDFA imaging: Stack of spirals dual echo (TE = 50, 2690µs, TI = 60ms) IR UTE research application. Subtracting the two echoes yielded short TE signal intensity (SI). IDFC imaging: stack of spirals dual echo IR UTE research application, TE = 50µs, TI = 200ms, acquired 15 minutes following Gadovist administration. Remnant tumor was contoured at each TP with T2, ADC, and DCE. Relative quantification; IDFA = IR UTE SI/Gluteal Muscle SI and IDFC = LGE IR UTE SI/Gluteal Muscle SI. The sum of normalized IDFA and IDFC SI within the remnant tumor at each TP was divided by the corresponding tumor volume yielding tumor intensity (TI) FA and FC accumulation estimates: TIFA and TIFC. Mean delivered dose within the treated volume to regions where post-RT IDFA and IDFC > 100% gluteal muscle SI was determined. Univariate relationships were evaluated using correlation coefficients (r). The coefficients of variation for TIFA = 10% and TIFC = 11%. IDFA and IDFC were observed pre-RT on the prostate gland periphery, and on RT and post RT within the prostate gland. IDFA and IDFC mean doses were 74% and 85% of prescription, respectively. Tumor regression was incomplete by post-RT. Initial tumor burden was inversely correlated with pre-RT TIFC (r = -0.98, p = .01). Tumor volume change post RT was inversely correlated with larger on-RT TIFA (r = -0.76) and post-RT TIFC (r = -0.78). In this small pilot study, results suggest that IDFA and IDFC may be associated with improved tumor regression. They also suggest higher delivered dose is related to regions of greater IDFC. Quantitative fibrosis may be an early marker of RT response. Caution must be taken when interpreting these results given the small sample size. Future work will include a larger cohort of patients and include post-RT imaging.

Longitudinal Analysis of Circulating Tumor DNA and Detection of Tumor Genomic Alterations Using Liquid Biopsy in Patients with Locally Advanced Esophagogastric Carcinoma

For locally advanced esophageal (E), esophagogastric junction (EGJ), and gastric (G) carcinoma, the standard treatment is neoadjuvant chemoradiotherapy followed by surgery. The curative goal is to control the tumor locally, prevent regional recurrence, and prevent or delay metastatic progression. Up to one-third of patients will achieve complete pathologic response rate (pCR) under this treatment. Yet disease recurrence can occur in one-third of patients after definitive treatment. Our study provides real-world longitudinal data of liquid biopsy to analyze circulating tumor deoxyribonucleotide acid (ctDNA) for minimal residual disease (MRD) as an informative marker for early therapeutic response, detectable disease, and risk for recurrence. Furthermore, the liquid biopsy reveals variable tumor-specific sequence alterations. A total of 8 patients with newly diagnosed locoregional esophagogastric cancers were evaluated with non-invasive plasma sample, collected at baseline, post-neoadjuvant chemoradiation, post-surgery, and serially as disease surveillance. Bespoke mPCR-NGS assay measured the ctDNA-based MRD levels and identified a comprehensive tumor-specific genomic profile. The primary outcome is assay recurrence compared to radiologic disease recurrence, defined as radiologic confirmed disease. Exploratory endpoints are used to examine the profile of tumor. Baseline ctDNA levels were detected in 8 newly diagnosed patients. Longitudinal testing showed a decrease in ctDNA in 4 patients and residual disease in 2 patients after the start of neoadjuvant therapy. 1 patient demonstrated pCR in conjunction with ctDNA clearance. Clearance of ctDNA may correlate to a favorable pCR and indicate a lower risk of relapse, guiding the strategy for adjuvant treatment. Personalized, tumor-informed sequence alterations of the 8 patients revealed a high frequency in TP53 alterations, which occurs early during development in esophagogastric cancer. This prospective study seeks to validate the application of ctDNA surveillance and tumor molecular alterations in a larger cohort after 5 years.

Pattern Analysis of Daily Lesion Volume Trajectories for Early Prediction of Glioblastoma Progression During MR-Linac Radiotherapy

Distinguishing between true progression (TP) and pseudoprogression (PP) post-radiotherapy (RT) is of paramount importance for treatment management of patients with glioblastoma (GBM). MR-Linac systems allow for daily monitoring of tumor changes throughout the course of RT. We hypothesized that the patterns of tumor volume change during RT may enable early prediction of treatment response. Using an IRB-approved prospective cohort of GBM patients undergoing 30 fractions of chemoRT to 60 Gy on a 0.35T MR-Linac, tumor/edema (tumor lesion) regions of interest (ROI) were contoured on daily T2-weighted treatment set-up scans. The obtained tumor lesion (TL) volume changes during treatment were smoothed with a moving average Gaussian window over time. Non-negative Matrix Factorization (NMF) was applied to the data matrix D (N x F), containing the trajectories in its rows for each patient, where N is the number of patients analyzed and F is the number of fractions. NMF represents D as a linear combination of three temporal (hidden) patterns and their weights in each individual trajectory. The same analysis was performed for ΔD, containing the changes in volumes with reference to the first fraction. The calculated weights were scaled in [0, 1], expressed as probabilities (by ℓ1-normalization) and used as features in Linear Discriminant Analysis (LDA). The LDA model was trained to differentiate between no progression (NP), PP and TP, and assessed by leave-one-subject-out cross-validation. Thirty-six patients were screened for inclusion: 9 were excluded due to no T2 lesion (resection cavity only). Of the remaining 27 GBM patients analyzed, 10 had no tumor growth on first post-RT diagnostic MRI, 6 were determined to have PP based on regression or long-term stability of findings, and 11 had TP due to continued progression of disease past 6 months, rapid patient death from disease, or tissue sampling showing active malignancy. With the use of only 2 features, LDA achieved an overall accuracy of 70.4% classifying correctly: 6 (60%), 4 (67%), and 9 (82%) patients with NP, PP, and TP, respectively. The temporal NMF patterns (monotonous decrease, rapid increase during the third part of the treatment, etc.) indicate that there is enough signal to classify patients' response based on the pattern tumor volume changes during RT. We identified tumor dynamics' patterns during RT, indicative of differential behavior of tumor growth between TP and PP. Although with a limited number of patients, these initial results suggest that tumor volume changes during treatment may provide early markers of treatment response. This could allow physicians to adapt/intensify treatment in real time for poorly responding patients. Next steps include automating the process of real-time tumor volume monitoring by incorporating a deep learning solution for automatic volume delineation on daily treatment set-up scans.

Evaluation of intra-abdominal pressure as an early marker of diuretic response in patients with cardiorenal syndrome

Evaluation of intra-abdominal pressure as an early marker of diuretic response in patients with cardiorenal syndrome

Associations of Multiparametric Breast MRI Features, Tumor-Infiltrating Lymphocytes, and Immune Gene Signature Scores Following a Single Dose of Trastuzumab in HER2-Positive Early-Stage Breast Cancer.

Dynamic biomarkers that permit the real-time monitoring of the tumor microenvironment response to therapy are an unmet need in breast cancer. Breast magnetic resonance imaging (MRI) has demonstrated value as a predictor of pathologic complete response and may reflect immune cell changes in the tumor microenvironment. The purpose of this pilot study was to investigate the value of breast MRI features as early markers of treatment-induced immune response. Fourteen patients with early HER2+ breast cancer were enrolled in a window-of-opportunity study where a single dose of trastuzumab was administered and both tissue and MRIs were obtained at the pre- and post-treatment stages. Functional diffusion-weighted and dynamic contrast-enhanced MRI tumor measures were compared with tumor-infiltrating lymphocytes (TILs) and RNA immune signature scores. Both the pre-treatment apparent diffusion coefficient (ADC) and the change in peak percent enhancement (DPE) were associated with increased tumor-infiltrating lymphocytes with trastuzumab therapy (r = -0.67 and -0.69, p < 0.01 and p < 0.01, respectively). Low pre-treatment ADC and a greater decrease in PE in response to treatment were also associated with immune-activated tumor microenvironments as defined by RNA immune signatures. Breast MRI features hold promise as biomarkers of early immune response to treatment in HER2+ breast cancer.

Molecular Markers of Early Immune Response in Tuberculosis: Prospects of Application in Predictive Medicine.

Tuberculosis (TB) remains an important public health problem and one of the leading causes of death. Individuals with latent tuberculosis infection (LTBI) have an increased risk of developing active TB. The problem of the diagnosis of the various stages of TB and the identification of infected patients in the early stages has not yet been solved. The existing tests (the tuberculin skin test and the interferon-gamma release assay) are useful to distinguish between active and latent infections. But these tests cannot be used to predict the development of active TB in individuals with LTBI. The purpose of this review was to analyze the extant data of the interaction of M. tuberculosis with immune cells and identify molecular predictive markers and markers of the early stages of TB. An analysis of more than 90 sources from the literature allowed us to determine various subpopulations of immune cells involved in the pathogenesis of TB, namely, macrophages, dendritic cells, B lymphocytes, T helper cells, cytotoxic T lymphocytes, and NK cells. The key molecular markers of the immune response to M. tuberculosis are cytokines (IL-1β, IL-6, IL-8, IL-10, IL-12, IL-17, IL-22b, IFNɣ, TNFa, and TGFß), matrix metalloproteinases (MMP-1, MMP-3, and MMP-9), and their inhibitors (TIMP-1, TIMP-2, TIMP-3, and TIMP-4). It is supposed that these molecules could be used as biomarkers to characterize different stages of TB infection, to evaluate the effectiveness of its treatment, and as targets of pharmacotherapy.

Real-world Outcomes and Predictive Biomarkers for 177Lutetium Prostate-specific Membrane Antigen Ligand Treatment in Metastatic Castration-resistant Prostate Cancer: A European Association of Urology Young Academic Urologists Prostate Cancer Working Group Multi-institutional Observational Study

BackgroundThe European Association of Urology guidelines include the lutetium-177 (177Lu) PSMA-617 prostate-specific membrane antigen (PSMA) ligand as a therapy option for metastatic castration-resistant prostate cancer (mCRPC). A major challenge in clinical practice is to pursue a personalized treatment approach based on robust predictive biomarkers. ObjectiveTo assess the performance of 177Lu PSMA in real-world practice and to elaborate clinical biomarkers for evaluating treatment responses. Design, setting, and participantsWe conducted a retrospective observational study including 233 patients with mCRPC treated with 177Lu PSMA in eight high-volume European centers. Outcome measurements and statistical analysisBaseline characteristics and clinical parameters during and after 177Lu PSMA treatment were documented. Correlations to treatment response were analyzed using χ2 and log-rank tests, with differences between groups with and without disease progression calculated using a Mann-Whitney U test. Univariate and multivariate-adjusted hazard ratios (HRs) were measured using Cox proportional hazards models. Results and limitationsA prostate-specific antigen (PSA) decrease of ≥30% was observed in 41.7%, 63.5%, and 77.8% of patients after the first, second, and third treatment cycle, respectively. Restaging performed via PSMA positron emission tomography-computed tomography revealed that 33.7% of patients had an imaging-based response, including two patients with a complete response, while 13.4% had stable disease. The median time to progression was 5 mo and the median time until the start of a consecutive antineoplastic therapy was 8.5 mo. Of importance, a PSA decrease ≥30% after the first two cycles of 177Lu PSMA (1 cycle: p = 0.0003; 2 cycles: p = 0.004), absolute PSA after the first three cycles (1 cycle: p = 0.011; 2 cycles: p = 0.0005; 3 cycles: p = 0.002), and a PSA doubling time >6 mo (p = 0.009) were significantly correlated to treatment response. Furthermore, gamma-glutamyl transferase ≤31 U/L at the start of 177Lu PSMA therapy was correlated with 1.5 times higher risk of progression for patients without but not with visceral metastases (p = 0.046). Conclusions177Lu PSMA is an effective treatment option in mCRPC in the real-world setting. A PSA decrease ≥30% after the first two cycles is an early marker of response that can be easily implemented in clinical practice. Patient summary177Lu PSMA is a radioactive agent approved for treatment of advanced prostate cancer. We reviewed its use outside of clinical trials for patients treated at eight European centers. We found that 177Lu PSMA is an effective treatment option in real-world practice. A PSA (prostate-specific antigen) decrease of ≥30% after the first two therapy cycles is an early indicator of response to treatment and can be used in personalizing treatments for patients.

Targeting metabolic vulnerabilities to overcome resistance to therapy in acute myeloid leukemia.

Malignant hematopoietic cells gain metabolic plasticity, reorganize anabolic mechanisms to improve anabolic output and prevent oxidative damage, and bypass cell cycle checkpoints, eventually outcompeting normal hematopoietic cells. Current therapeutic strategies of acute myeloid leukemia (AML) are based on prognostic stratification that includes mutation profile as the closest surrogate to disease biology. Clinical efficacy of targeted therapies, e.g., agents targeting mutant FMS-like tyrosine kinase 3 (FLT3) and isocitrate dehydrogenase 1 or 2, are mostly limited to the presence of relevant mutations. Recent studies have not only demonstrated that specific mutations in AML create metabolic vulnerabilities but also highlighted the efficacy of targeting metabolic vulnerabilities in combination with inhibitors of these mutations. Therefore, delineating the functional relationships between genetic stratification, metabolic dependencies, and response to specific inhibitors of these vulnerabilities is crucial for identifying more effective therapeutic regimens, understanding resistance mechanisms, and identifying early response markers, ultimately improving the likelihood of cure. In addition, metabolic changes occurring in the tumor microenvironment have also been reported as therapeutic targets. The metabolic profiles of leukemia stem cells (LSCs) differ, and relapsed/refractory LSCs switch to alternative metabolic pathways, fueling oxidative phosphorylation (OXPHOS), rendering them therapeutically resistant. In this review, we discuss the role of cancer metabolic pathways that contribute to the metabolic plasticity of AML and confer resistance to standard therapy; we also highlight the latest promising developments in the field in translating these important findings to the clinic and discuss the tumor microenvironment that supports metabolic plasticity and interplay with AML cells.

Factors leading to supranormal cardiac index in pediatric pulmonary hypertension patients treated with parenteral prostanoid therapy.

Parenteral prostanoid therapy (PPT) can result in supranormal cardiac index (SCI; >4 L/min/m2) in pediatric pulmonary hypertension (PPH) patients. We evaluated the incidence, hemodynamic factors, and outcomes associated with SCI in PPH. This retrospective cohort study included 22 PPH patients on PPT from 2005 to 2020. Hemodynamic profiles were compared between the baseline and 3-6 month follow-up catheterization in the SCI and non-SCI cohorts. Cox regression analysis examined time to composite adverse outcome (CAO; Potts shunt, lung transplant, or death) controlling for initial disease severity. SCI developed in 17 (77%) patients, of whom 11 (65%) developed SCI within 6 months. The SCI cohort was characterized by significant augmentation of cardiac index (CI) and stroke volume (SV) as well as reductions in systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR). Conversely, the non-SCI cohort had unchanged SV despite a modest rise in CI as well as persistent vasoconstriction. After median follow-up of 4.3 years (range 0.2-13 years), non-SCI patients were at significantly increased risk for the CAO (5/5: three deaths, two Potts shunts) compared withSCI patients (5/17: two deaths, three lung transplants; adjusted hazard ratio 14.0 [95% confidence interval: 2.1-91.3], p < 0.001). A majority of PPH patients developed SCI within 6-12 months of starting PPT and demonstrated lower risk of adverse outcomes compared withnon-SCI patients. These data suggest that change in SVR and SV after 3-6 months of PPT may be early markers of therapeutic response and prognosis.

ELISA F29 -A therapeutic efficacy biomarker in Chagas disease: Evaluation in pediatric patients treated with nifurtimox and followed for 4 years post-treatment.

Measurement of the success of antitrypanosomal treatment for Chagas disease is difficult, particularly in the chronic phase of the disease, because anti-Trypanosoma cruzi antibodies persist in serum for prolonged periods. We studied the effects of nifurtimox administered by two different treatment regimens on the T. cruzi calcium-binding flagellar protein F29 in children diagnosed with Chagas disease measured using an enzyme-linked immunosorbent assay (ELISA) technique (ELISA F29). In a phase 3, randomized, double-blind, parallel-group, historically controlled study (ClinicalTrials.gov NCT02625974), blood samples obtained from children diagnosed with Chagas disease and treated with nifurtimox for either 60 days or 30 days were analyzed using an ELISA with an F29 recombinant protein as the antigen, as well as conventional serological tests (recombinant ELISA and indirect hemagglutination assay). In an exploratory approach, serological response to nifurtimox treatment was evaluated for 4 years post-treatment. In both treatment groups, the number of patients with negative ELISA F29 values increased over the period of observation. The incidence rate of negative seroconversion using ELISA F29 was 22.94% (95% CI: 19.65%, 26.63%) in the 60-day treatment group and 21.64% (95% CI: 17.21%, 26.86%) in the 30-day treatment group. In the subpopulation of patients who tested seropositive for F29 before nifurtimox treatment, 88 patients (67.7%) in the 60-day regimen and 39 patients (59.1%) in the 30-day regimen were F29 seronegative at 4 years post-treatment. All patients who had a positive ELISA F29 test at baseline and seroconverted to negative measured by conventional serology reached seronegativity in ELISA F29 earlier than in conventional serology. The results demonstrate a serological response to treatment with nifurtimox measured by the ELISA F29 test in children diagnosed with Chagas disease. The F29-based ELISA can be considered a potential early marker of response to antitrypanosomal therapy for Chagas disease. ClinicalTrials.gov NCT02625974.

MFAST-SeqS based aneuploidy score in circulating cell-free DNA and role as early response marker in patients with metastatic prostate cancer treated with androgen receptor signaling inhibitor.

5058 Background: Several treatment modalities in metastatic castration resistant prostate cancer (mCRPC) are available to prolong progression-free and overall survival. With the arrival of additional treatment modalities, the need for accurate monitoring of treatment response is becoming more eminent and research for biomarkers pivotal. Cell-free circulating tumor DNA (ctDNA) has emerged as a promising prognostic and predictive biomarker. Several techniques have been employed for the detection and characterization of ctDNA within the total pool of cell-free DNA (cfDNA), one of which is the modified Fast Aneuploidy Screening Test-Sequencing System (mFAST-SeqS). This affordable and robust assay enables the quantitation of a sample’s ctDNA using a genome-wide aneuploidy score (GWA). Our aim was to investigate whether estimation of the GWA by mFAST-SeqS can be used to evaluate early response to treatment and predict response to treatment at baseline in patients with mCRPC. Methods: We prospectively enrolled mCRPC patients before start of treatment with androgen receptor signaling inhibitor (ARSI) abiraterone or enzalutamide. Blood samples were collected at baseline before start of treatment (BL, n= 134) and at an early treatment time point during treatment (ET, n= 20). We isolated cfDNA from plasma collected at both time points using the QiaSymphony or Maxwell system, and performed mFAST-SeqS on 1 ng cfDNA by amplifying and sequencing long interspaced nuclear elements (LINE-1) throughout the genome. The GWA-scores were calculated by taking the summed square of individual Z scores per chromosome arm relative to healthy controls. GWA-score was dichotomized in high (GWAhigh) and low (GWAlow), based on the previously described cut-off of 5. Clinical outcome, defined as treatment duration with ARSI, was compared for patients with a GWAhigh and GWAlow score at baseline and at an early time point. In addition, conversion of GWA score from baseline to early time point was explored. Results: Median age at start of treatment was 68.5 years (inter-quartile range (IQR): 63-73). Median time between start treatment and blood draw at BL and ET was 3 (IQR: 0-10 days before treatment) and 28 (IQR: 18-62 days during treatment) days, respectively. Median number of prior therapy lines was 1 (IQR: 0-10). Treatment duration was significantly shorter in the GWAhigh group versus the GWAlow group both at BL and at ET in patients treated with ARSI (BL: p&lt;0.001, log-rank test, median 221 and 82 days; ET: p&lt;0.01, log-rank test, median 123 and 42 days). Conclusions: The genome-wide aneuploidy score, based on mFAST-SeqS of cfDNA, is a useful tool to predict response to ARSI in patients with mCRPC. The current dataset will be extended to 199 samples at baseline and 78 samples at early time point, and also include mCRPC patients treated with taxanes. Clinical trial information: NCT01855477 , NTR732 .

Synovial fluid mitochondrial DNA concentration reflects the degree of cartilage damage after naturally occurring articular injury

To evaluate mitochondrial DNA (mtDNA) release from injured chondrocytes and investigate the utility of synovial fluid mtDNA concentration in early detection of posttraumatic osteoarthritis. We measured mtDNA release using four models of osteoarthritis: in vitro interleukin-1β stimulation of cultured equine chondrocytes, ex vivo mechanical impact of bovine cartilage explants, in vivo mechanical impact of equine articular cartilage, and naturally occurring equine intraarticular fracture. In our in vivo model, one group was treated with an intraarticular injection of the mitoprotective peptide SS-31 following cartilage injury. mtDNA content was quantified using qPCR. For naturally occurring cases of joint injury, clinical data (radiographs, arthroscopic video footage) were scored for criteria associated with degenerative joint disease. Chondrocytes released mtDNA in the acute time frame following inflammatory and mechanical cellular stress in vitro. mtDNA was increased in equine synovial fluid following experimental and naturally occurring injury to the joint surface. In naturally occurring posttraumatic osteoarthritis, we found a strong positive correlation between the degree of cartilage damage and mtDNA concentration (r=0.80, P=0.0001). Finally, impact-induced mtDNA release was mitigated by mitoprotective treatment. Changes in synovial fluid mtDNA occur following joint injury and correlate with the severity of cartilage damage. Mitoprotection mitigates increases in synovial fluid mtDNA suggesting that mtDNA release may reflect mitochondrial dysfunction. Further investigation of mtDNA as a potentially sensitive marker of early articular injury and response to mitoprotective therapy is warranted.