A systematic analysis of oncogenic gene fusions in primary colon cancer

Genomic rearrangements that give rise to oncogenic gene fusions can offer actionable targets for cancer therapy. Here we present a systematic analysis of oncogenic gene fusions among a clinically well-characterized, prospectively collected set of 278 primary colon cancers spanning diverse tumor stages and clinical outcomes. Gene fusions and somatic genetic variations were identified in fresh frozen clinical specimens by Illumina RNA-sequencing, the STAR fusion gene detection pipeline, and GATK RNA-seq variant calling. We considered gene fusions to be pathogenically relevant when recurrent, producing divergent gene expression (outlier analysis), or as functionally important (e.g., kinase fusions). Overall, 2.5% of all specimens were defined as harboring a relevant gene fusion (kinase fusions 1.8%). Novel configurations of BRAF, NTRK3, and RET gene fusions resulting from chromosomal translocations were identified. An R-spondin fusion was found in only one tumor (0.35%), much less than an earlier reported frequency of 10% in colorectal cancers. We also found a novel fusion involving USP9X-ERAS formed by chromothripsis and leading to high expression of ERAS, a constitutively active RAS protein normally expressed only in embryonic stem cells. This USP9X–ERAS fusion appeared highly oncogenic on the basis of its ability to activate AKT signaling. Oncogenic fusions were identified only in lymph node–negative tumors that lacked BRAF or KRAS mutations. In summary, we identified several novel oncogenic gene fusions in colorectal cancer that may drive malignant development and offer new targets for personalized therapy

Optimizing Nanopore sequencing-based detection of structural variants enables individualized circulating tumor DNA-based disease monitoring in cancer patients

Here, we describe a novel approach for rapid discovery of a set of tumor-specific genomic structural variants (SVs), based on a combination of low coverage cancer genome sequencing using Oxford Nanopore with an SV calling and filtering pipeline. We applied the method to tumor samples of high-grade ovarian and prostate cancer patients and validated on average ten somatic SVs per patient with breakpoint-spanning PCR mini-amplicons. These SVs could be quantified in ctDNA samples of patients with metastatic prostate cancer using a digital PCR assay. The results suggest that SV dynamics correlate with and may improve existing treatment-response biomarkers such as PSA. https://github.com/UMCUGenetics/SHARC

The Factor Structure and Presentation of Depression Among HIV-Positive Adults in Uganda

Depression is one of the most prevalent psychiatric comorbidities of HIV and one of the greatest barriers to HIV self-care and adherence. Despite this, little consensus exists on how to best measure depression among people living with HIV/AIDS (PLWHA) in African settings. Measurement of depression among PLWHA may be confounded by somatic symptoms. Some research recommends excluding these items to enhance measurement validity; sensitivity may be lost with this approach. We sought to characterize depression among a cohort (N = 453) of PLWHA initiating antiretroviral therapy in Uganda via factor analysis of a widely used measure of depression, the Hopkins Symptom Checklist (HSCLD). Common factor analysis was performed, associations between HSCLD and the Mental Health subscale of the Medical Outcomes Study HIV (MOS-HIV) estimated, and a Cronbach’s alpha calculated to examine validity. Factor analysis yielded two factors: (1) somatic-cognitive symptoms and (2) behavioral disengagement. Persons with more versus less advanced disease (CD4 cell count of ≤200 cells/mm(3)) showed no statistically significant differences in depression scores (1.7 vs. 1.7, P ≥ 0.5). Both factors were significantly associated with the MOS-HIV (P <.01). Factor one was highly reliable (α = .81); factor two had only modest reliability (α = .65). Somatic-cognitive symptoms of depression and disengagement from life’s activities appear to be distinct components of depression in this sample. Consideration of somatic items may be valuable in identifying depression in this setting

Risk of COVID-19 after natural infection or vaccinationResearch in context

Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health

Risk of COVID-19 after natural infection or vaccinationResearch in context

Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health