bims-tumhet 2024-12-15 papers

Clin Epigenetics. 2024 Dec 06. 16(1): 178

BRCA1 & BRCA2 methylation as a prognostic and predictive biomarker in cancer: Implementation in liquid biopsy in the era of precision medicine.

Maria Panagopoulou, Theodoros Panou, Anastasios Gkountakos, Gesthimani Tarapatzi, Makrina Karaglani, Ioannis Tsamardinos, Ekaterini Chatzaki.

BACKGROUND: BReast CAncer gene 1 (BRCA1) and BReast CAncer gene 2 (BRCA2) encode for tumor suppressor proteins which are critical regulators of the Homologous Recombination (HR) pathway, the most precise and important DNA damage response mechanism. Dysfunctional HR proteins cannot repair double-stranded DNA breaks in mammalian cells, a situation called HR deficiency. Since their identification, pathogenic variants and other alterations of BRCA1 and BRCA2 genes have been associated with an increased risk of developing mainly breast and ovarian cancer. Interestingly, HR deficiency is also detected in tumors not carrying BRCA1/2 mutations, a condition termed "BRCAness".
MAIN TEXT: One of the main mechanisms causing the BRCAness phenotype is the methylation of the BRCA1/2 promoters, and this epigenetic modification is associated with carcinogenesis and poor prognosis mainly among patients with breast and ovarian cancer. BRCA1 promoter methylation has been suggested as an emerging biomarker of great predictive significance, especially concerning Poly (ADP-ribose) Polymerase inhibitors (PARP inhibitor-PARPi) responsiveness, along with or beyond BRCA1/2 mutations. However, as its clinical exploitation is still insufficient, the impact of BRCA1/2 promoter methylation status needs to be further evaluated. The current review aims to gather the latest findings about the mechanisms that underline BRCA1/2 function as well as the molecular characteristics of tumors associated with BRCA1/2 defects, by focusing on DNA methylation. Furthermore, we critically analyze their translational meaning and the validity of BRCA methylation biomarkers in predicting treatment response.
CONCLUSIONS: We believe that BRCA1/2 methylation alone or combined with other biomarkers in a clinical setting is expected to change the scenery in prognosis and predicting treatment response in multiple cancer types and is worthy of further attention. The quantitative BRCA1 promoter methylation assessment might predict treatment response in PARPi and analysis of BRCA1/2 methylation in liquid biopsy might define patient subgroups at different time points that may benefit from PARPi. Finally, we suggest a pipeline that could be implemented in liquid biopsy to aid precision pharmacotherapy in BRCA-associated tumors.

Keywords: BRCA1; BRCA2; Breast cancer; Cancer; DNA promoter methylation; Liquid biopsy; Ovarian; PARP inhibitors

DOI: https://doi.org/10.1186/s13148-024-01787-8

Cancer Cell. 2024 Dec 09. pii: S1535-6108(24)00440-9. [Epub ahead of print]42(12): 2045-2063.e10

Chemotherapy induces myeloid-driven spatially confined T cell exhaustion in ovarian cancer.

Anti-tumor immunity is crucial for high-grade serous ovarian cancer (HGSC) prognosis, yet its adaptation upon standard chemotherapy remains poorly understood. Here, we conduct spatial and molecular characterization of 117 HGSC samples collected before and after chemotherapy. Our single-cell and spatial analyses reveal increasingly versatile immune cell states forming spatiotemporally dynamic microcommunities. We describe Myelonets, networks of interconnected myeloid cells that contribute to CD8+ T cell exhaustion post-chemotherapy and show that M1/M2 polarization at the tumor-stroma interface is associated with CD8+ T cell exhaustion and exclusion, correlating with poor chemoresponse. Single-cell and spatial transcriptomics reveal prominent myeloid-T cell interactions via NECTIN2-TIGIT induced by chemotherapy. Targeting these interactions using a functional patient-derived immuno-oncology platform demonstrates that high NECTIN2-TIGIT signaling in matched tumors predicts responses to immune checkpoint blockade. Our discovery of clinically relevant myeloid-driven spatial T cell exhaustion unlocks immunotherapeutic strategies to unleash CD8+ T cell-mediated anti-tumor immunity in HGSC.

Keywords: immuno-oncology; multiomics; ovarian cancer; spatial biology; tumor microenvironment

DOI: https://doi.org/10.1016/j.ccell.2024.11.005

Gynecol Oncol. 2024 Dec 12. pii: S0090-8258(24)01221-6. [Epub ahead of print]192 145-154

Prognostic value of circulating tumor DNA at diagnosis and its early decrease after one cycle of neoadjuvant chemotherapy for patients with advanced epithelial ovarian cancer. An ancillary analysis of the CHIVA phase II GINECO trial.

OBJECTIVE: To evaluate the prognostic impact of circulating tumor DNA (ctDNA) detection at diagnosis (T0) and its early decrease after one cycle (T1) of neoadjuvant chemotherapy (NACT) in patients with advanced epithelial ovarian cancer (EOC) included in the CHIVA trial (NCT01583322).
METHODS: Blood samples were collected at T0 and before each administration of NACT. Circulating tumor DNA detection was performed by next-generation sequencing. Multivariate analysis was performed. A p-value of 0.05 was considered significant. Progression-free survival (PFS) and overall survival (OS) were compared between groups defined by ctDNA kinetic profile. Cox survival model was used to search variables associated with PFS and OS. Kaplan-Mayer curve was used to graphically express the differences in PFS and OS. A log-rank test compared the two curves.
RESULTS: 188 patients were included. Blood samples were available for 168 patients at T0 and for 160 patients at T0 and T1 to assess ctDNA ratio kinetics. At T0, 107 patients (63.7 %) had detectable ctDNA. At T1, 137 (85.6 %) patients had negative ctDNA or a decrease of more than 80 %. There was a significant benefit in either PFS (p = 0.0017) or OS (p = 0.0036) in favor of early decrease of ctDNA ratio. A favorable decrease was associated with a greater likelihood of being able to perform CRS (OR: 3.94 (CI95 % 1.45-10.70), p = 0.0074).
CONCLUSIONS: Early decrease of ctDNA ratio can provide prognostic information early in the management of patients, allowing a more accurate information to patients and an early preparation for CRS (prehabilitation).

Keywords: Biomarker; Circulating tumor DNA; Epithelial ovarian cancer; Gynecologic oncology; Liquid biopsy; Next generation sequencing

DOI: https://doi.org/10.1016/j.ygyno.2024.12.004

Cancer Cell. 2024 Nov 28. pii: S1535-6108(24)00444-6. [Epub ahead of print]

Advances in liquid biopsy: From exploration to practical application.

Catherine Alix-Panabières, Klaus Pantel.

Liquid biopsy has received tremendous attention as a non-invasive approach for detecting and tracking cancer. Here, we discuss the latest work on circulating tumor DNA and circulating tumor cells with respect to clinical applications, including cancer screening, early detection of relapse, real-time monitoring of therapeutic efficacy, and detection of therapeutic targets and resistance mechanisms.

DOI: https://doi.org/10.1016/j.ccell.2024.11.009

Hematology Am Soc Hematol Educ Program. 2024 12 06. 2024(1): 321-325

Are TP53 mutations all alike?

Terrence N Wong, Daniel C Link.

TP53 is mutated in 10 to 15% of cases of acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) and is associated with a previous exposure to cytotoxic therapy, complex cytogenetic abnormalities, and a poor prognosis. Recent data have established the importance of TP53-mutant allele status, the determination of which requires specific genetic testing. Compared with monoallelic disease, multihit TP53-mutant AML/MDS is associated with chromosomal abnormalities and decreased overall survival. Most TP53 mutations are missense mutations that localize to the DNA binding domain. Hot-spot mutations involving residues R175, Y220, G245, R248, R273, or R282 represent approximately 35% of all TP53 missense mutations in AML/MDS. There is evidence that these hot-spot mutations may have dominant negative or gain-of-function properties. Here we review this evidence and discuss its potential impact on patient outcomes and clinical management.

DOI: https://doi.org/10.1182/hematology.2024000556