Expression of the Stress Response Oncoprotein LEDGF/p75 in Human Cancer: A Study of 21 Tumor Types

Oxidative stress-modulated signaling pathways have been implicated in carcinogenesis and therapy resistance. The lens epithelium derived growth factor p75 (LEDGF/p75) is a transcription co-activator that promotes resistance to stress-induced cell death. This protein has been implicated in inflammatory and autoimmune conditions, HIV-AIDS, and cancer. Although LEDGF/p75 is emerging as a stress survival oncoprotein, there is scarce information on its expression in human tumors. The present study was performed to evaluate its expression in a comprehensive panel of human cancers. Transcript expression was examined in the Oncomine cancer gene microarray database and in a TissueScan Cancer Survey Panel quantitative polymerase chain reaction (Q-PCR) array. Protein expression was assessed by immunohistochemistry (IHC) in cancer tissue microarrays (TMAs) containing 1735 tissues representing single or replicate cores from 1220 individual cases (985 tumor and 235 normal tissues). A total of 21 major cancer types were analyzed. Analysis of LEDGF/p75 transcript expression in Oncomine datasets revealed significant upregulation (tumor vs. normal) in 15 out of 17 tumor types. The TissueScan Cancer Q-PCR array revealed significantly elevated LEDGF/p75 transcript expression in prostate, colon, thyroid, and breast cancers. IHC analysis of TMAs revealed significant increased levels of LEDGF/p75 protein in prostate, colon, thyroid, liver and uterine tumors, relative to corresponding normal tissues. Elevated transcript or protein expression of LEDGF/p75 was observed in several tumor types. These results further establish LEDGF/p75 as a cancer-related protein, and provide a rationale for ongoing studies aimed at understanding the clinical significance of its expression in specific human cancers

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

TMAs used for immunohistochemical analysis of LEDGF/p75 protein expression in tumors.

<p>TMAs used for immunohistochemical analysis of LEDGF/p75 protein expression in tumors.</p

Differential expression of LEDGF/p75 protein analyzed by immunohistochemistry in 21 human tumor types and corresponding normal tissues.

<p>TMAs stained with antibody against LEDGF/p75 were scored as: 0 = no staining, 1 = low, staining, 2 = moderate staining, 3 = strong staining. Scored tissues were pooled in two groups: low staining (scores 0 and 1) and high staining (scores 2 and 3). <i>P</i> values comparing the immunohistochemical expression (high vs. low) of LEDGF/p75 protein between tumor tissues and corresponding normal tissues was determined using the Fisher's exact test. Bold numbers denote significant <i>P</i> values. n/a-Not applicable.</p

Transcript expression of LEDGF/p75 in eight human cancer types determined by TissueScan Cancer Q-PCR analysis.

<p>Data were analyzed using the ΔΔCt method with values normalized to β-actin levels. The y-axis represents the induction fold of the LEDGF/p75 mRNA level in eight cancer types (n = 9) compared to matching normal adjacent tissues (n = 3) in the array. Error bars displays the range of standard error. * <i>P</i><0.05. <i>P</i> values were determined with Student's t-test.</p

Elevated immunohistochemical expression of LEDGF/p75 protein in five tumor types compared to corresponding normal tissues.

<p>Tissue microarrays were stained with antibody against LEDGF/p75, and the individual cores were blindly scored using the following scale: 0 = no staining, 1 = low staining, 2 = moderate staining, 3 = strong staining. Scored tissues were pooled into two groups: low staining (scores 0 and 1, dark bars) and high staining (scores 2 and 3, light bars). The percentage of specimens in the two staining categories was plotted for tumor tissues compared to normal (including disease-free normal and normal adjacent) tissues. *<i>P</i><0.05; **<i>P</i><0.01. <i>P</i> values were determined with Fisher's exact test.</p

Association of LEDGF/p75 protein expression in colon, liver, prostate, thyroid and uterine tumors with patients' clinical characteristics.

<p>Bold numbers denote significant <i>P</i> values. <i>P</i> values for the association of immunohistochemical LEDGF/p75 expression (high vs. low comparison) in tumors with patients' age and sex were calculated using Fisher's exact test, while those for tumor stage were calculated using Kendall's tau b correlation analysis. At the time of surgical excision of the tissues, the median age of donors was 62 years for colon cancer, 53 years for liver cancer, 66 years for prostate cancer, 48 years for thyroid cancer, and 70 years for uterine cancer. The tumor stages (pT1 to pT4) correspond to pathologic tumor stages T1 through T4 used in the TNM system of cancer staging. The TNM system is based on the extent of the tumor (T), the extent of spread to the lymph nodes (N), and the presence of distant metastasis (M). A number is added to each letter (eg. T1, T2, T3, T4) to indicate the size or extent of the primary tumor and the extent of cancer spread. N/A, Not applicable; N/D, No data available.</p

LEDGF/p75 transcript expression in human tumors determined by analysis of Oncomine cancer gene microarray database.

<p>*P<0.05.</p

Identification of LEDGF/p75 specific antibody by immunoblotting in PC-3 cells with transient LEDGF/p75 knockdown.

<p>Cells were transfected with siLEDGF/p75 to induce transient knockdown of LEDGF/p75. PC-3 cells transfected with small interfering scrambled RNA duplex (siSD) served as corresponding control. Immunoblotting analysis tested the specific reactivity of all the antibodies against LEDGF/PSIP1. All the blot pairs (siSD and siLEDGF/p75) for each antibody were derived from the same blot.</p