Prognostic impact of copy number alterations and tumor mutational burden in carcinoma of unknown primary.

INTRODUCTION: Chromosomal aberrations are known to drive metastatic spread, but their profile is still elusive in carcinoma of unknown primary (CUP). Therefore, the aim of this study was to characterize the chromosomal aberration pattern in CUP depending on histological and clinical features and to assess its prognostic impact together with chromothripsis, tumor mutational burden (TMB), microsatellite instability (MSI), and mutational profiles as potential prognostic biomarkers. METHODS: Chromosomal aberrations and chromothripsis were detected by methylation-based copy number variation (CNV) analysis, whereas TMB and MSI were calculated based on large next-generation sequencing (NGS) panels. Putative primaries were assigned by consensus between two independent oncologists. RESULTS: CNV losses varied depending on putative primaries and were more abundant in patients harboring TP53 mutations and/or deletions 17p. CNV loss was prognostically adverse in localized CUP treated with surgery and/or radiotherapy, but not in disseminated poor-risk CUP treated with palliative chemotherapy. CNV loss also worsened the prognosis in squamous cell CUP. Chromothripsis was detected in 18/59 (30.5%) patients without prognostic effect. TMB was highest in cases with MSI, squamous cell histology, and with lung, anal or cervical putative primaries. CONCLUSION: Overall, CNV, chromothripsis, TMB, and MSI profiles in CUP are reminiscent of biological characteristics known from other cancer entities without a unifying CUP-specific signature. Markedly, high-level CNV loss is an adverse predictive biomarker in localized but not disseminated chemotherapy-treated CUP. This implies that chromosomal losses drive CUP progression, but also increase susceptibility to chemotherapy, with both effects apparently leveling out in disseminated CUP.

On the coupling of protein and water dynamics in confinement: Spatially resolved molecular dynamics simulation studies.

To ascertain protein-water couplings in confinement, we exploit that molecular dynamics simulations enable full control and systematic variation of the model system as well as componentwise and spatially resolved analyses. We use an elastin-like molecule and vary the thickness of the hydration shell by producing confinements of desired shape and size. Moreover, we tune the rigidity of the confinement. The approach reveals prominent dynamical couplings at the protein-water interface in combination with strong spatial variation of both protein and water dynamics. Explicitly, changes in the mobility of the hydration shell in response to altered confinement conditions are accompanied by changes in the mobility of the protein surface, leading to a relation of respective correlation times. Moreover, with increasing distance to the protein-water interface, water dynamics speeds up and protein dynamics slow down, where, however, internal and global protein motions show quantitative differences. These findings indicate that an understanding of biological functions requires consideration of mutual dependencies of protein and water dynamics, strong mobility gradients across the protein molecule and the hydration shell, and differences between internal and tumbling motions. In addition, we observe that the effect of the confining walls is very strong but short ranged. As a consequence, protein dynamics is significantly altered under severe confinement conditions, whereas bulk-like behavior is recovered for confinement sizes larger than ∼4.3 nm, corresponding to hydration levels above ∼1.5 g/g.

Nivolumab and ipilimumab in recurrent or refractory cancer of unknown primary: a phase II trial.

Cancer of unknown primary has a dismal prognosis, especially following failure of platinum-based chemotherapy. 10-20% of patients have a high tumor mutational burden (TMB), which predicts response to immunotherapy in many cancer types. In this prospective, non-randomized, open-label, multicenter Phase II trial (EudraCT 2018-004562-33; NCT04131621), patients relapsed or refractory after platinum-based chemotherapy received nivolumab and ipilimumab following TMBhigh vs. TMBlow stratification. Progression-free survival (PFS) represented the primary endpoint; overall survival (OS), response rates, duration of clinical benefit and safety were the secondary endpoints. The trial was prematurely terminated in March 2021 before reaching the preplanned sample size (n = 194). Among 31 evaluable patients, 16% had a high TMB ( > 12 mutations/Mb). Overall response rate was 16% (95% CI 6-34%), with 7.7% (95% CI 1-25%) vs. 60% (95% CI 15-95%) in TMBlow and TMBhigh, respectively. Although the primary endpoint was not met, high TMB was associated with better median PFS (18.3 vs. 2.4 months) and OS (18.3 vs. 3.6 months). Severe immune-related adverse events were reported in 29% of cases. Assessing on-treatment dynamics of circulating tumor DNA using combined targeted hotspot mutation and shallow whole genome sequencing as part of a predefined exploratory analysis identified patients benefiting from immunotherapy irrespective of initial radiologic response.

Local ablative treatment with surgery and/or radiotherapy in single-site and oligometastatic carcinoma of unknown primary.

BACKGROUND: Single-site carcinoma of unknown primary (CUP) is recognised as a distinct favourable subtype in the European Society of Medical Oncology (ESMO) classification. There is broad consensus that these patients are candidates for local ablative treatment strategies with surgery and/or radiotherapy, but data on their outcomes are scarce. PATIENTS AND METHODS: In this study, we have addressed the prospects of cure and prognostic factors in a retrospective cohort of 63 patients who were eligible for local treatment at our centre. RESULTS: Median event-free (EFS) and overall survival (OS) were 15.6 months and 52.5 months, respectively. Of 61 patients who received local treatment, 20 (32.8%) remained event-free over a median follow-up of 28 months. Baseline clinical parameters including affected organ, number, volume and histology of metastases had no significant impact on prognosis, whereas deleterious TP53 mutations and DNA copy number loss emerged as independent adverse risk factors with respect to EFS. Surgical treatment was associated with improved OS as compared to radiation-based therapy. CONCLUSION: Our study advocates to pursue localised treatment with surgery and/or radiotherapy whenever feasible and implies that genetic parameters might additionally determine the clinical course of single-site CUP patients.