Chronic lymphocytic leukemia (CLL) is the most common form of leukemia among adults in Western countries. Despite the introduction of targeted therapies, including first-line Bruton\'s tyrosine kinase inhibitor (BTKi) treatment, CLL remains largely incurable. Frequent disease relapses occur due to remaining treatment-resistant CLL cells, calling for novel therapies to eliminate minimal residual disease (MRD). Peptide-based vaccination targeting human leucocyte antigen (HLA)-presented CLL-associated antigens represents a promising, low-side-effect therapeutic option to optimize treatment responses and eliminate residual tumor cells by inducing an anti-leukemic immune response. The iVAC-XS15-CLL01 trial is an open-label, first-in-human (FIH) Phase I trial, evaluating the CLL-VAC-XS15 vaccine in CLL patients undergoing BTKi-based therapy. The vaccine was developed from HLA-presented CLL-associated antigen peptides, identified through comparative mass-spectrometry-based immunopeptidome analyses of CLL versus healthy samples in a previous study. To facilitate rapid and cost-effective deployment, vaccine peptides are selected for each patient from a pre-manufactured \"peptide warehouse\" based on the patient\'s individual HLA allotype and CLL immunopeptidome. The trial enrolls 20 CLL patients, who receive up to three doses of the vaccine, adjuvanted with the toll-like-receptor (TLR) 1/2 ligand XS15 and emulsified in Montanide ISA 51 VG. The primary objective of the iVAC-XS15-CLL01 trial is to assess the safety and immunogenicity of the CLL-VAC-XS15 vaccine. Secondary objectives are to evaluate the vaccine impact on MRD, progression-free survival, and overall survival, as well as comprehensive immunophenotyping to characterize vaccine-induced T-cell responses. This Phase I trial aims to advance CLL treatment by enhancing immune-mediated disease clearance and guiding the design of subsequent Phase II/III trials to implement a new therapeutic strategy for CLL patients.

Although there has been significant advancement in the identification and management of colorectal cancer (CRC) in recent years, there is still room for improvement in the current standard treatment regimen. One area of concern is the lack of reliable tumor markers to predict treatment efficacy and guide tailored care. Due to its dynamic, effective, and non-invasive benefits over tissue biopsy, the detection of minimal or molecular residual lesions (MRD) based on circulating tumor DNA (ctDNA) is beneficial to the clinical development of drugs for patients with CRC after radical treatment, as well as for continuous monitoring of tumor recurrence and malignancy molecular gene evolution. The detection of ctDNA can currently be used to guide individual postoperative auxiliary treatment decisions (upgrade or downgrade treatment) in CRC, stratify the risk of clinical recurrence more precisely, and predict the risk of recurrence in advance of imaging examination, according to a large number of observational or prospective clinical studies. With increasing clarity comes the possibility of selecting a regimen of treatment based on postoperative ctDNA, which also improves the accuracy of clinical recurrence risk assessment for CRC. Therefore, it is anticipated that the identification of ctDNA would alter the current framework for dealing with CRC and lead to individualized, stratified precision therapy; however, additional confirmation will require subsequent high-quality, prospective, large-scale randomized controlled studies. This article will provide an overview of the definition and clinical significance of MRD, the primary indications and technological challenges for MRD detection, along with the advancement in clinical research about ctDNA detection following radical resection of the CRC.

Lymphoma is a highly heterogeneous lymphohematopoietic tumor. As our understanding of the biological and pathological characteristics of lymphoma improves, we are identifying an increasing number of lymphoma subtypes. Genotyping has enhanced our ability to diagnose, treat, and monitor the prognosis of lymphoma. Despite significant improvements in treatment effectiveness, traditional methods for assessing disease response and monitoring prognosis are imperfect, and there is no significant improvement in overall remission rates for lymphoma patients. Minimal Residual Disease (MRD) is often indicative of refractory disease or early relapse. For lymphoma patients, personalized MRD monitoring techniques offer an efficient means to estimate disease remission levels, predict early relapse risk, and assess the effectiveness of new drug regimens. In this review, we delve into the MRD procedures in lymphoma, including sample selection and requirements, detection methods and their limitations and advantages, result interpretation. Besides, we also introduce the clinical applications of MRD detection in lymphoma.

BACKGROUND: Precursor B-cell acute lymphoblastic leukemia (B-ALL) is the most common cancers in children. Failure of induction chemotherapy is a major factor leading to relapse and death in children with B-ALL. Given the importance of altered metabolites in the carcinogenesis of pediatric B-ALL, studying the metabolic profile of children with B-ALL during induction chemotherapy and in different minimal residual disease (MRD) status may contribute to the management of pediatric B-ALL.
METHODS: We collected paired peripheral blood plasma samples from children with B-ALL at pre- and post-induction chemotherapy and analyzed the metabolomic profiling of these samples by ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS). Healthy children were included as controls. We selected metabolites that were depleted in pediatric B-ALL and analyzed the concentrations in pediatric B-ALL samples. In vitro, we study the effects of the selected metabolites on the viability of ALL cell lines and the sensitivity to conventional chemotherapeutic agents in ALL cell lines.
RESULTS: Forty-four metabolites were identified with different levels between groups. KEGG pathway enrichment analyses revealed that dysregulated linoleic acid (LA) metabolism and arginine (Arg) biosynthesis were closely associated with pediatric B-ALL. We confirmed that LA and Arg were decreased in pediatric B-ALL samples. The treatment of LA and Arg inhibited the viability of NALM-6 and RS4;11 cells in a dose-dependent manner, respectively. Moreover, Arg increased the sensitivity of B-ALL cells to L-asparaginase and daunorubicin.
CONCLUSIONS: Arginine increases the sensitivity of B-ALL cells to the conventional chemotherapeutic drugs L-asparaginase and daunorubicin. This may represent a promising therapeutic approach.

Background: Until now, limited clinical significance had been reported for disseminated tumor cells (DTCs) in gynecologic malignancies. DTCs were previously reported not to be associated with established risk factors, L1CAM immunoreactivity, and outcome in endometrial carcinoma (EC). This study\'s primary objective was to investigate potential correlations of DTCs in the bone marrow (BM) of EC patients with disease-related survival, and a secondary objective was to evaluate associations between molecular classification of EC and DTCs. Methods: Patients treated for primary EC at Tuebingen University women\'s hospital between 2003 and 2016 were identified. A total of 402 patients with a complete set of BM cytology, molecular, and clinical data were evaluable. Results: DTC occurrence was distributed equally among all four molecular groups (p = 0.651). DTC positivity was associated with a less favorable disease-free survival (HR: 1.86, 95% CI: 1.03-3.36, p = 0.036) and progression-free survival (HR: 1.86, 95% CI: 1.01-3.44, p = 0.045). Presence of DTCs was associated with a higher frequency of distant disease recurrence (p = 0.017). Conclusions: In line with our previous findings, tumor cell dissemination is not associated with molecular features in our large cohort of primary EC patients. Since DTCs seem to be associated with survival and location of disease recurrence, further studies are needed to decisively define their role in EC survival.

In the recent decade, analysis of circulating tumor DNA (ctDNA) has improved cancer care by allowing for rapid detection of actionable molecular targets. A new generation of circulating DNA tests is now becoming available commercially. These tests are characterized by a superior limit of detection of 0.01% vaF or better, allowing for the detection of radiologically occult molecular residual disease (MRD). MRD tests have the potential to revolutionize neoadjuvant and adjuvant treatment. In addition, these tests can be used as tumor markers to assess disease response. We reviewed the current evidence for the use of high-sensitivity MRD assays with particular focus on the genitourinary tumors. Multiple studies have now been reported in urothelial, renal, and recently testicular carcinoma. We find that the sensitivity varies across tumor types in the adjuvant setting and may reach a high of 100% in urothelial cancer. Specificity in tumor-informed MRD appears to be preserved across tumor types (98%-100%). Several trials are now prospectively validating MRD testing in biomarker integral studies, mainly in urothelial carcinoma.

Donor lymphocyte infusions (DLIs) are often recommended products after allogeneic hematopoietic stem cell transplant to increase graft - versus - leukemia effect. More success rate of DLI has been reported in relapsed posttransplant chronic myeloid leukemia. Whatever the indication for DLI, mortality related to post-DLI infusion is 5%-20%, and more than one-third of patients will develop acute and/or chronic graft versus host disease (GVHD) after DLI. We report two cases where DLIs were used for residual disease after posttransplant. Both of DLI went uneventful. None of the patient\'s developed signs of GVHD postinfusion. Although both patients expired with different causes, none were related to DLI infusion. Information from published literature suggests that DLI should be administered early after relapse or as a prophylactic strategy in patients receiving T-cell-depleted grafts, and patients with aggressive diseases may benefit from disease reduction before DLI. However, further evidence is required to evaluate its efficacy, especially in relapsed or residual hematological malignancies.

Circulating tumor DNA (ctDNA), a fragment of tumor DNA found in the bloodstream, has emerged as a revolutionary tool in cancer management. This review delves into the biology of ctDNA, examining release mechanisms, including necrosis, apoptosis, and active secretion, all of which offer information about the state and nature of the tumor. Comprehensive DNA profiling has been enabled by methods such as whole genome sequencing and methylation analysis. The low abundance of the ctDNA fraction makes alternative techniques, such as digital PCR and targeted next-generation exome sequencing, more valuable and accurate for mutation profiling and detection. There are numerous clinical applications for ctDNA analysis, including non-invasive liquid biopsies for minimal residual disease monitoring to detect cancer recurrence, personalized medicine by mutation profiling for targeted therapy identification, early cancer detection, and real-time evaluation of therapeutic response. Integrating ctDNA analysis into routine clinical practice creates promising avenues for successful and personalized cancer care, from diagnosis to treatment and follow-up.

Efforts to cure BCR::ABL1 B cell acute lymphoblastic leukemia (Ph+ ALL) solely through inhibition of ABL1 kinase activity have thus far been insufficient despite the availability of tyrosine kinase inhibitors (TKIs) with broad activity against resistance mutants. The mechanisms that drive persistence within minimal residual disease (MRD) remain poorly understood and therefore untargeted. Utilizing 13 patient-derived xenograft (PDX) models and clinical trial specimens of Ph+ ALL, we examined how genetic and transcriptional features co-evolve to drive progression during prolonged TKI response. Our work reveals a landscape of cooperative mutational and transcriptional escape mechanisms that differ from those causing resistance to first generation TKIs. By analyzing MRD during remission, we show that the same resistance mutation can either increase or decrease cellular fitness depending on transcriptional state. We further demonstrate that directly targeting transcriptional state-associated vulnerabilities at MRD can overcome BCR::ABL1 independence, suggesting a new paradigm for rationally eradicating MRD prior to relapse. Finally, we illustrate how cell mass measurements of leukemia cells can be used to rapidly monitor dominant transcriptional features of Ph+ ALL to help rationally guide therapeutic selection from low-input samples.

Breast cancer remains a leading cause of cancer mortality in women globally. Despite advancements in systemic therapy, the risk of distant recurrence persists even after such treatment and may be linked to disseminated tumor cells (DTCs). Variability in molecular characteristics between primary tumors (PTs) and distant metastases underscores the need to comprehensively understand metastatic pathways. This retrospective study investigated discrepancies between HER2 expression in PTs and DTCs and their implications for survival outcomes in 201 early breast cancer (EBC) patients. We found a significant association between HER2 expression in PTs and DTCs when classifying tumors as HER2-high/low/negative. Patients whose HER2 status was discordant between PTs and DTCs exhibited worse distant disease-free survival than those with concordant status. Multivariate analysis confirmed the HER2 status of DTCs as an independent prognostic factor for distant DFS. These findings emphasize the importance of assessing HER2 expression in DTCs and its potential implications for tailored therapy strategies in EBC. Furthermore, prospective trials are needed to validate these findings and explore targeted therapies based on the molecular characteristics of DTCs.