Guillaume Bataillon

Dissecting the Origin of Heterogeneity in Uterine and Ovarian Carcinosarcomas

Gynecologic carcinosarcomas (CS) are biphasic neoplasms composed of carcinomatous (C) and sarcomatous (S) malignant components. Because of their rarity and histologic complexity, genetic and functional studies on CS are scarce and the mechanisms of initiation and development remain largely unknown. Whole-genome analysis of the C and S components reveals shared genomic alterations, thus emphasizing the clonal evolution of CS. Reconstructions of the evolutionary history of each tumor further reveal that C and S samples are composed of both ancestral cell populations and component-specific subclones, supporting a common origin followed by distinct evolutionary trajectories. However, while we do not find any recurrent genomic features associated with phenotypic divergence, transcriptomic and methylome analyses identify a common mechanism across the cohort, the epithelial-to-mesenchymal transition (EMT), suggesting a role for nongenetic factors in inflicting changes to cellular fate. Altogether, these data accredit the hypothesis that CS tumors are driven by both clonal evolution and transcriptomic reprogramming, essential for susceptibility to transdifferentiation upon encountering environmental cues, thus linking CS heterogeneity to genetic, transcriptomic, and epigenetic influences. Significance: We have provided a detailed characterization of the genomic landscape of CS and identified EMT as a common mechanism associated with phenotypic divergence, linking CS heterogeneity to genetic, transcriptomic, and epigenetic influences.

Circulating HPV DNA as a Marker for Early Detection of Relapse in Patients with Cervical Cancer

Abstract Purpose: Almost all cervical cancers are caused by human papillomavirus (HPV) and patients with advanced stage are at high risk for relapse. Circulating HPV DNA (HPV ctDNA) may serve as a residual tumor marker at the end of chemoradiation or to predict relapse during the follow-up period. Experimental Design: We analyzed serum samples from 94 HPV16- or HPV18-related CCs from the BioRAIDs prospective cohort. Samples were collected before and after treatment and during an 18-month follow-up period. Using digital droplet PCR (ddPCR), we assessed the relevance of circulating HPV E7 gene as a marker for residual disease compared to HPV integration site and PIK3CA mutations. Finally, the prognostic impact of circulating HPV E7 gene was assessed with its prediction value of relapse. Results: HPV E7 gene was the most sensitive tumor marker, superior to both HPV integration sites and PIK3CA mutations in serum. Circulating HPV DNA (HPV ctDNA) was detected in 63% (59/94) of patients, before treatment. HPV ctDNA detection in serum sample was associated with high FIGO stage (P = 0.02) and para-aortic lymph node involvement (P = 0.01). The level of HPV ctDNA was positively correlated with HPV copy number in the tumor (R = 0.39, P < 0.001). Complete clearance of HPV ctDNA by the end of treatment was significantly associated with a longer PFS (P < 0.0001). Patients with persistent HPV ctDNA in serum relapsed with a median time of 10 months (range, 2–15) from HPV ctDNA detection. Conclusions: HPV ctDNA detection is a useful marker to predict relapse in cervical cancer. See related commentary by Wentzensen and Clarke, p. 5733

Unraveling the Tumor Microenvironment and PD-L1 Expression across Tissue Types in High-Grade Serous Ovarian Cancer in the NeoPembrOV/GINECO Phase II Randomized Trial

Abstract Purpose: To describe PD-L1 expression across tissue types and its associated tumor microenvironment and to investigate how it affects its predictive value for response to pembrolizumab in treatment-naïve patients with ovarian cancer included in the NeoPembrOV phase II trial (NCT03275506). Experimental Design: PD-L1 expression was assessed for 85 patients (56 on metastasis and 29 on tubo-ovary) using tumor proportion score (TPS) and immune cell (IC) score, considering positivity if ≥1% and high expression if ≥5%. RNA sequencing and multiplex immunofluorescence were conducted. The Australian Ovarian Cancer Study was used as an external validation cohort. Results: PD-L1 was primarily expressed by tumor cells in tubo-ovaries and by ICs in metastases. The IC score assessed on the metastases was associated with a longer progression-free survival in the pembrolizumab arm compared with the control arm. Compared with tubo-ovaries, metastases were enriched in T and B cells as well as in granzyme B (GZMB) CD8 cytotoxic T-cell signatures. In metastases, the IC score was associated with immune infiltration and overexpression of additional immune checkpoints, such as IDO1, LAG3, and ICOS, whereas TPS was associated with cell proliferation, immune infiltration, and IFN-γ pathways. In tubo-ovaries, TPS was associated with pathways linked to cell proliferation and antigen presentation but was depleted in activated immune pathways, and CD274 expression was correlated with hypoxia and PI3K/Akt/mTOR signaling. Conclusions: Distinct PD-L1 expression patterns across tissue types are associated with different biological pathways and tumor microenvironments in ovarian cancer, affecting PD-L1 predictive value. Our results provide novel insights into high-grade serous ovarian cancer biology for tailoring immunotherapy in patients with ovarian cancer.

Dynamic ctDNA Assessment in Cervical and Anal Canal Tumors: Optimizing Follow-up and Clinical Outcomes

After definitive radiotherapy (RT) treatment (with or without chemotherapy), cervical and anal canal neoplasms frequently exhibit disease persistence or recurrence. Due to the local inflammatory process post-treatment, response assessment by imaging (current gold standard) is limited, often necessitating multiple follow-ups and repeated invasive biopsies. Conventional follow-up is complex and costly, requiring equipment from secondary and tertiary services, trained radiologists, and patient exposure to radiation and contrast. In this context of human papillomavirus(HPV)-related neoplasms, recent studies have demonstrated the role of ctDNA (circulating tumor DNA) in assessing the risk of recurrence or disease progression, providing a rationale for using the tool in two fronts: * Optimizing follow-up based on serial monitoring of ctDNA; * Selecting patients with positive ctDNA after RT, who are at high risk of recurrence, for treatment intensification. Monitoring with ctDNA as a standalone follow-up tool in cases evolving with negative ctDNA after RT has the potential to replace imaging exams, being a minimally invasive test performed on a peripheral blood sample. Currently, ctDNA testing has expensive methodologies not available in the Unified Health System (SUS). This project aims to develop a methodology for ctDNA evaluation focused on HPV ctDNA research that is low-cost and executable in SUS, as well to assess the accuracy of this test in the population with HPV-related tumors. Additionally, we will evaluate whether the early introduction of immunotherapy in patients with positive ctDNA after definitive treatment can increase cure rates. Immunotherapy already has a well-defined role in the treatment of metastatic HPV-related neoplasms. Recently, the use of anti-programmed death-1 (anti-PD1) has also shown benefits in patients with locally advanced cervical cancer with a high risk of recurrence who are candidates for chemoradiotherapy (CRT). Therefore, its use focused on HPV-related tumors, as well as a better understanding of which patients benefit from this strategy, warrants further investigation.