bims-tumhet Biomed News
on Tumor Heterogeneity
Issue of 2023‒10‒08
five papers selected by
Sergio Marchini, Humanitas Research

  1. Nat Rev Clin Oncol. 2023 Oct 02.
      Ovarian carcinoma is characterized by heterogeneity at the molecular, cellular and anatomical levels, both spatially and temporally. This heterogeneity affects response to surgery and/or systemic therapy, and also facilitates inherent and acquired drug resistance. As a consequence, this tumour type is often aggressive and frequently lethal. Ovarian carcinoma is not a single disease entity and comprises various subtypes, each with distinct complex molecular landscapes that change during progression and therapy. The interactions of cancer and stromal cells within the tumour microenvironment further affects disease evolution and response to therapy. In past decades, researchers have characterized the cellular, molecular, microenvironmental and immunological heterogeneity of ovarian carcinoma. Traditional treatment approaches have considered ovarian carcinoma as a single entity. This landscape is slowly changing with the increasing appreciation of heterogeneity and the recognition that delivering ineffective therapies can delay the development of effective personalized approaches as well as potentially change the molecular and cellular characteristics of the tumour, which might lead to additional resistance to subsequent therapy. In this Review we discuss the heterogeneity of ovarian carcinoma, outline the current treatment landscape for this malignancy and highlight potentially effective therapeutic strategies in development.
  2. Ann Oncol. 2023 Oct 03. pii: S0923-7534(23)04007-3. [Epub ahead of print]
    OReO/ENGOT-ov38 investigators
      BACKGROUND: Poly(ADP-ribose) polymerase (PARP) inhibitor maintenance therapy is standard of care for some patients with advanced ovarian cancer. We evaluated the efficacy and safety of PARP inhibitor rechallenge.PATIENTS AND METHODS: This randomized, double-blind, multicenter trial (NCT03106987) enrolled patients with platinum-sensitive relapsed ovarian cancer who had received one prior PARP inhibitor therapy for ≥18 and ≥12 months in the BRCA-mutated and non-BRCA-mutated cohorts, respectively, following first-line chemotherapy or for ≥12 and ≥6 months, respectively, following a second or subsequent line of chemotherapy. Patients were in response following their last platinum-based chemotherapy regimen and were randomized 2:1 to maintenance olaparib tablets 300 mg twice daily or placebo. Investigator-assessed progression-free survival (PFS) was the primary endpoint.
    RESULTS: 74 patients in the BRCA-mutated cohort were randomized to olaparib and 38 to placebo, and 72 patients in the non-BRCA-mutated cohort were randomized to olaparib and 36 to placebo; >85% of patients in both cohorts had received ≥3 prior lines of chemotherapy. In the BRCA-mutated cohort, median PFS was 4.3 months with olaparib versus 2.8 months with placebo (hazard ratio [HR] 0.57; 95% confidence interval [CI] 0.37-0.87; P = 0.022); 1-year PFS rates were 19% versus 0% (Kaplan-Meier estimates). In the non-BRCA-mutated cohort, median PFS was 5.3 months for olaparib versus 2.8 months for placebo (HR 0.43; 95% CI 0.26-0.71; P = 0.0023); 1-year PFS rates were 14% versus 0% (Kaplan-Meier estimates). No new safety signals were identified with olaparib rechallenge.
    CONCLUSIONS: In ovarian cancer patients previously treated with one prior PARP inhibitor and at least two lines of platinum-based chemotherapy, maintenance olaparib rechallenge provided a statistically significant, albeit modest, PFS improvement over placebo in both the BRCA-mutated and non-BRCA-mutated cohorts, with a proportion of patients in the maintenance olaparib rechallenge arm of both cohorts remaining progression free at 1 year.
    Keywords:  OReO/ENGOT-ov38; PARP inhibitor; olaparib; platinum-sensitive relapsed ovarian cancer; rechallenge
  3. Nucleic Acids Res. 2023 Oct 04. pii: gkad782. [Epub ahead of print]
      The development of spatial transcriptome sequencing technology has revolutionized our comprehension of complex tissues and propelled life and health sciences into an era of spatial omics. However, the current availability of databases for accessing and analyzing spatial transcriptomic data is limited. In response, we have established CROST (, a comprehensive repository of spatial transcriptomics. CROST encompasses high-quality samples and houses 182 spatial transcriptomic datasets from diverse species, organs, and diseases, comprising 1033 sub-datasets and 48 043 tumor-related spatially variable genes (SVGs). Additionally, it encompasses a standardized spatial transcriptome data processing pipeline, integrates single-cell RNA sequencing deconvolution spatial transcriptomics data, and evaluates correlation, colocalization, intercellular communication, and biological function annotation analyses. Moreover, CROST integrates the transcriptome, epigenome, and genome to explore tumor-associated SVGs and provides a comprehensive understanding of their roles in cancer progression and prognosis. Furthermore, CROST provides two online tools, single-sample gene set enrichment analysis and SpatialAP, for users to annotate and analyze the uploaded spatial transcriptomics data. The user-friendly interface of CROST facilitates browsing, searching, analyzing, visualizing, and downloading desired information. Collectively, CROST offers fresh and comprehensive insights into tissue structure and a foundation for understanding multiple biological mechanisms in diseases, particularly in tumor tissues.
  4. Nature. 2023 Oct;622(7981): 41-47
      Scientists have been trying to identify every gene in the human genome since the initial draft was published in 2001. In the years since, much progress has been made in identifying protein-coding genes, currently estimated to number fewer than 20,000, with an ever-expanding number of distinct protein-coding isoforms. Here we review the status of the human gene catalogue and the efforts to complete it in recent years. Beside the ongoing annotation of protein-coding genes, their isoforms and pseudogenes, the invention of high-throughput RNA sequencing and other technological breakthroughs have led to a rapid growth in the number of reported non-coding RNA genes. For most of these non-coding RNAs, the functional relevance is currently unclear; we look at recent advances that offer paths forward to identifying their functions and towards eventually completing the human gene catalogue. Finally, we examine the need for a universal annotation standard that includes all medically significant genes and maintains their relationships with different reference genomes for the use of the human gene catalogue in clinical settings.