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Molecular Profiling of Bladder Cancer Xenografts Defines Relevant Molecular Subtypes and Provides a Resource for Biomarker Discovery
No full textBladder cancer (BLCA) genomic profiling has identified molecular subtypes with distinct clinical characteristics and variable sensitivities to frontline therapy. BLCAs can be categorized into luminal or basal subtypes based on their gene expression. We comprehensively characterized nine human BLCA cell lines (UC3, UC6, UC9, UC13, UC14, T24, SCaBER, RT4V6 and RT112) into molecular subtypes using orthotopic xenograft models. Patient-derived, luciferase-tagged BLCA cell lines were cultured in vitro and engrafted into bladders of NSG mice. Tumor growth was monitored using bioluminescence imaging and mRNA-based molecular classification was used to characterize xenografts into molecular subtypes. RNAseq analysis and basal, luminal, and epithelial-mesenchymal transition (EMT) marker expression revealed distinct patterns; certain cell lines expressed predominantly basal or luminal markers while others demonstrated mixed expression. SCaBER expressed high basal and EMT markers and low luminal markers, consistent with a true basal cell. RT4V6 was a true luminal cell line, displaying only high luminal makers. UC13, T24 and UC3 only showed increased expression of EMT markers. RT112, UC6, UC9 and UC14 expressed basal, luminal, and EMT markers. Immunohistochemical analysis validated our findings. Ki67 was assessed as a continuous percentage of positively stained cells. Morphological assessment of xenografts included H&E and α-SMA staining. These findings will allow for the rational use of appropriate models to develop targeted therapies to overcome or manipulate mechanisms of treatment resistance in BLCA
Spatial Transcriptome Reveals Histology-Correlated Immune Signature Learnt by Deep Learning Attention Mechanism on H&E-stained Images for Ovarian Cancer Prognosis
No full textBackground: The ability to predict the prognosis of patients with ovarian cancer can greatly improve disease management. However, the knowledge on the mechanism of the prediction is limited. We sought to deconvolute the attention feature learnt by a deep learning convolutional neural networks trained with whole-slide images (WSIs) of hematoxylin-and-eosin (H&E)-stained tumor samples using spatial transcriptomic data.
Methods: In this study, 773 WSIs of H&E-stained tumor sections from 335 patients with treatment naïve high-grade serous ovarian cancer who were included in The Cancer Genome Atlas (TCGA) Pan-Cancer study were used to train, and validate, and to test a ResNet101 CNN model modified with attention mechanism. WSIs from patients in an independent cohort were used to further evaluate the model.
Results: The prognostic value of the predicted H&E-based survival scores from the trained model on patient survival was evaluated. The attention signals learnt by the model were then examined their correlation with immune signatures using spatial transcriptome. After validating the model with the testing datasets, pathway enrichment analysis showed that the H&E-based survival score significantly correlated with certain immune signatures and this was validated spatially using spatial transcriptome data generated from ovarian cancer FFPE samples by correlating the selected signature and attention signal.
Conclusions: In conclusion, attention mechanism might be useful to identify regions for their specific immune activities. This could guide future pathological study for the useful immunological features that are important in modulating the prognosis of ovarian cancer patients
Treatment Group-Specific Inferences in Phase III Randomized Oncology Trials
No full textBackground: Estimation of comparative treatment effects between randomized groups is well-supported in randomized trials. By contrast, treatment group-specific inferences are challenging, as patients are selectively chosen for enrollment, and such inferences are formally discouraged by the CONSORT guidelines. The present study is the first-large scale assessment of the proportion of phase III oncology trials that present treatment group-specific inferences.
Methods: Published phase III randomized oncology trials were screened from ClinicalTrials.gov. Treatment group-specific inferences were defined by the presence of 95% CI or standard error for treatment-specific outcomes.
Results: A total of 774 phase III trials enrolling 568,080 patients were included. Treatment group-specific inferences were present in 58% of trials (446 of 774), and appeared to be increasing over time (adjusted odds ratio for the publication year, 1.11; 95% CI, 1.06 to 1.17; p \u3c 0.0001). Of the remaining 328 trials, 49 (6%) described group-specific outcomes with measures of variability, such as interquartile range, and 279 (36%) provided point estimates only (e.g., median) for group outcomes.
Interpretation: The majority of published phase III oncology trials present treatment group-specific inferences. However, this inference lacks statistical support, as patients are not randomly sampled from the underlying population, and conflicts with CONSORT guidelines. While ongoing methodological efforts to improve the transportability of treatment group-specific inferences are promising, conventional attempts to generalize treatment-specific outcomes from randomized trials may be misleading. Instead of inference, treatment group-specific outcomes should be described using measures of variability
A Serum Biomarker Panel and Miniarray Detection System for Tracking Disease Activity and Flare Risk in Lupus Nephritis
Get PDFIntroduction: Lupus nephritis (LN) leads to end stage renal disease (ESRD), and early diagnosis and disease monitoring of LN could significantly reduce the risk. however, there is not such a system clinically. In this study we aim to develop a biomarker-panel based point-of-care system for LN.
Methods: Immunoassay screening combined with genomic expression databases and machine learning techniques was used to identify a biomarker panel of LN. A quantitative biomarker-panel mini-array (BPMA) system was developed and the sensitivity, specificity, reproducibility, and stability of the were examined. The performance of BPMA in disease monitoring was validated with machine models using a larger cohort of LN. The BPMA was also used to determine LN flare using a machine-learning generated flare score (F-Score).
Results: Among 32 promising LN serum biomarkers, VSIG4, TNFRSF1b, VCAM1, ALCAM, OPN, and IgG anti-dsDNA antibody were selected to constitute an LN biomarker Panel, which exhibited excellent discriminative value in distinguishing LN from healthy controls (AUC = 1.0) and active LN from inactive LN (AUC = 0.92), respectively. Also, the 6-biomarker panel exhibited a strong correlation with key clinical parameters of LN. A multiplexed immunoarray was constructed with the 6-biomarker panel (named BPMA-S6 thereafter). An LN-specific 8-point standard curve was generated for each protein biomarker. Cross-reaction between these biomarkers was minimal (\u3c 1%). BPMA-S6 test results were highly correlated with those from ELISA (Spearman\u27s correlation: fluorescent detection, rs = 0.95; colorimetric detection, rs = 0.91). The discriminative value of BPMA-S6 for LN was further validated using an independent cohort (AUC = 0.94). Using a longitudinal cohort of LN, the derived F-Score exhibited superior discriminative value in the training dataset (AUC = 0.92) and testing dataset (AUC=0.82) to distinguish flare vs remission.
Conclusion: BPMA-S6 may represent a promising point-of-care test (POCT) for the diagnosis, disease monitoring, and assessment of LN flare
Early Treatment Discontinuation in Patients With Deficient Mismatch Repair or Microsatellite Instability High Metastatic Colorectal Cancer Receiving Immune Checkpoint Inhibitors
No full textBackground: Immune checkpoint inhibitors (ICIs) are recommended to treat patients with deficient mismatch repair/microsatellite instability high (dMMR/MSI-H) metastatic colorectal cancer (mCRC). Pivotal trials have fixed a maximum ICI duration of 2 years, without a compelling rationale. A shorter treatment duration has the potential to improve patients\u27 quality of life and reduce both toxicity and cost without compromising efficacy. Here we examine whether early treatment discontinuation (ETD) before 13 months in patients without progressive disease (PD) can lead to similar long-term disease control compared with a longer treatment duration (LTD).
Methods: To assess whether ETD is associated with similar outcomes compared with LTD, we assembled an international cohort of patients with dMMR/MSI-H mCRC treated with ICIs who stopped treatment for a reason other than PD within 395 days (ETD group) and compared them to those who continued for \u3e395 days (LTD group). Outcomes were adjusted for patient/tumor characteristics. Primary endpoint was progression-free survival (PFS) and secondary endpoints were objective response rate (ORR), overall survival (OS) and safety.
Results: Of 976 patients, 137 and 394 were allocated to the ETD and LTD groups, respectively. In the ETD group, treatment was discontinued due to toxicity (n=56), objective response (n=43), surgery (n=28), patient decision (n=2) or other reasons (n=8). Baseline characteristics were well balanced between the two groups: 22% in both groups received both anti-programmed death-(ligand) 1 (anti-PD-(L)1) + anti-cytotoxic T-lymphocyte antigen-4 (anti-CTLA-4); all others received anti-PD-(L)1 monotherapy. ORR to ICIs was 81% in both groups. Median duration of treatment was ~7 months in the ETD and ~24 months in the LTD group. After a median follow-up of 44 months (IQR: 30-67), similar PFS (HR: 0.92, 95% CI: 0.60 to 1.40, p=0.69) and OS (HR: 1.15, 95% CI: 0.66 to 1.99, p=0.62) from the start of ICIs were observed in ETD and LTD patients. In the ETD group, 28 (20%) patients had a PFS event and 9 restarted ICIs with a disease control rate of 66%.
Conclusions: In our international series of dMMR/MSI-H mCRC, ETD of ICIs in the absence of PD did not seem detrimental in terms of PFS and OS compared with continuing treatment beyond 1 year. Randomized clinical trials to compare short and long treatment duration are now warranted
Phase I Trial of Hydroxychloroquine To Enhance Palbociclib and Letrozole Efficacy in ER+/HER2- Breast Cancer
No full textEndocrine therapy with CDK4/6 inhibitors is standard for estrogen receptor-positive, HER2-negative metastatic breast cancer (ER+/HER2- MBC), yet clinical resistance develops. Previously, we demonstrated that low doses of palbociclib activate autophagy, reversing initial G1 cell cycle arrest, while high concentrations induce off-target senescence. The autophagy inhibitor hydroxychloroquine (HCQ) induced on-target senescence at lower palbociclib doses. We conducted a phase I trial (NCT03774472 registered in ClinicalTrials.gov on 8/20/2018) of HCQ (400, 600, 800 mg/day) with palbociclib (75 mg/day continuous) and letrozole, using a 3 + 3 design. Primary objectives included safety, tolerability, and determining the recommended phase 2 dose (RP2D) of HCQ. Secondary objectives included tumor response and biomarker analysis. Fourteen ER+/HER2- MBC patients were evaluable [400 mg (n = 4), 600 mg (n = 4), 800 mg (n = 6)]. Grade 3 adverse events (AEs) included hematological (3 at 800 mg), skin rash (2 at 600 mg), and anorexia (1 at 400 mg), with no serious AEs. The best responses were partial (2), stable (11), and progression (1). Tumor reductions ranged from 11% to 30%, with one 55% increase. The two partial responders sustained tumor size reductions of 30% to 55% over an extended treatment period, lasting nearly 300 days. Biomarker analysis in responders demonstrated significant decreases in Ki67, Rb, and nuclear cyclin E levels and increases in autophagy markers p62 and LAMP1, suggesting a correlation between these biomarkers and treatment response. This phase I study demonstrated that HCQ is safe and well-tolerated and the RP2D was established at 800 mg/day with continuous low-dose palbociclib (75 mg/day) and letrozole (2.5 mg/day). These findings suggest that adding HCQ could potentially enhance the efficacy of low-dose palbociclib and standard letrozole therapy, pending verification in larger randomized studies
Use of the Protein Misfolding Cyclic Amplification for food safety and drug discovery
No full textPrion diseases are fatal neurodegenerative disorders caused by the misfolding of the normal prion protein (PrPC) into its infectious form (PrPSc). While the zoonotic potential of chronic wasting disease (CWD) remains uncertain, the presence of prions in food products raises public health concerns. Additionally, therapeutic strategies for prion diseases remain limited. This thesis presents a methodological exploration of the Protein Misfolding Cyclic Amplification (PMCA) technique to address these challenges in two key areas: (1) detecting CWD prions in processed meats subjected to common cooking procedures, and (2) identifying potential anti-prion compounds through a high-throughput PMCA adaptation.
Our results demonstrate that PMCA effectively detected CWD prions in a range of processed meat products, with an unexpected increase in prion detectability following grilling and boiling, suggesting enhanced prion accessibility post-cooking. Despite this, these prions failed to convert the human prion protein in PMCA reactions, indicating a limited zoonotic risk under the conditions/materials tested.
In parallel, a modified 96-well plate PMCA screening strategy identified eight promising compounds with inhibitory effects on PrPSc formation. Notably, these candidates exhibited diverse properties, including both hydrophilic and hydrophobic profiles, with some compounds previously linked to amyloidogenic pathway inhibition.
This study highlights the versatility of the PMCA technique for both, food safety assessments and screening anti-prion compounds. The results presented in this thesis work stress the importance of exploring prion strain diversity, refining PMCA protocols, and validating potential inhibitors in in vivo models for future therapeutic development
The Influence of the Microbiome on Radiotherapy and DNA Damage Responses
No full textColorectal cancer (CRC) is one of the most prevalent cancers in terms of diagnosis and mortality. Radiotherapy (RT) remains a mainstay of CRC therapy. As RT relies on DNA damage to promote tumor cell death, the activity of cellular DNA damage repair pathways can modulate cancer sensitivity to therapy. The gut microbiome has been shown to influence intestinal health and is independently associated with CRC development, treatment responses and outcomes. The microbiome can also modulate responses to CRC RT through various mechanisms such as community structure, toxins and metabolites. In this review we explore the use of RT in the treatment of CRC and the molecular factors that influence treatment outcomes. We also discuss how the microbiome can promote radiosensitivity versus radioprotection to modulate RT outcomes in CRC. Understanding the molecular interaction between the microbiome and DNA repair pathways can assist with predicting responses to RT. Once described, these connections between the microbiome and RT response can also be used to identify actionable targets for therapeutic development
Measuring and Interpreting Individual Differences in Fetal, Infant, and Toddler Neurodevelopment
No full textAs scientists interested in fetal, infant, and toddler (FIT) neurodevelopment, our research questions often focus on how individual children differ in their neurodevelopment and the predictive value of those individual differences for long-term neural and behavioral outcomes. Measuring and interpreting individual differences in neurodevelopment can present challenges: Is there a standard way for the human brain to develop? How do the semantic, practical, or theoretical constraints that we place on studying development influence how we measure and interpret individual differences? While it is important to consider these questions across the lifespan, they are particularly relevant for conducting and interpreting research on individual differences in fetal, infant, and toddler neurodevelopment due to the rapid, profound, and heterogeneous changes happening during this period, which may be predictive of long-term outcomes. This article, therefore, has three goals: 1) to provide an overview about how individual differences in neurodevelopment are studied in the field of developmental cognitive neuroscience, 2) to identify challenges and considerations when studying individual differences in neurodevelopment, and 3) to discuss potential implications and solutions moving forward
An Intranasally Administered IgM Protects Against Antigenically Distinct Subtypes of Influenza a Viruses
No full textEngineering broadly neutralizing monoclonal antibodies (mAbs) targeting the hemagglutinin (HA) of Influenza A virus (IAV) is a promising approach for intervention of seasonal flu. However, HA plasticity often leads to resistant strains that compromise mAb potency as bivalent IgGs. Here we hypothesize that multimerization of anti-IAV antibodies as IgMs can enhance coverage and neutralization potency. Here, we construct 18 IgM antibodies from known broadly neutralizing IgGs targeting different IAV HA epitopes and evaluate their breadth and potency of neutralization against distinct H1N1 and H3N2 IAVs. The IgM version of receptor binding site-specific IgG F045-092 shows increased breadth and antiviral potency compared to its parental IgG. Engineered IgM molecules overcome IAV strain resistance by expanded avidity, providing potent neutralization in vitro at sub-nanomolar ranges while retaining parental IgG specificity. Intranasal delivery of engineered IgM-F045-092 in female mice demonstrates efficient bio-retention in nasal cavities and lungs, offering protection against lethal doses of H1N1 and H3N2 IAV when administered prophylactically. Optimal epitope selection, trans-crosslinking, decavalent avidity, and intranasal administration contribute to the broader protection and potency of engineered IgM antibodies against diverse IAV subtypes