In normal cells, aberrant oncogene expression leads to the accumulation of cytotoxic metabolites, including reactive oxygen species (ROS), which can cause oxidative DNA-damage and apoptosis as an intrinsic barrier against neoplastic disease. The c-Myc oncoprotein is overexpressed in many lymphoid cancers due to c-myc gene amplification and/or 8q24 chromosomal translocations. Intriguingly, p53 is a downstream target of c-Myc and hematological malignancies, such as adult T-cell leukemia/lymphoma (ATL), frequently contain wildtype p53 and c-Myc overexpression. We therefore hypothesized that p53-regulated pro-survival signals may thwart the cell's metabolic anticancer defenses to support oncogene-activation in lymphoid cancers. Here we show that the Tp53-induced glycolysis and apoptosis regulator (TIGAR) promotes c-myc oncogene-activation by the human T-cell leukemia virus type-1 (HTLV-1) latency-maintenance factor p30^II, associated with c-Myc deregulation in ATL clinical isolates. TIGAR prevents the intracellular accumulation of c-Myc-induced ROS and inhibits oncogene-induced cellular senescence in ATL, acute lymphoblastic leukemia, and multiple myeloma cells with elevated c-Myc expression. Our results allude to a pivotal role for p53-regulated antioxidant signals as mediators of c-Myc oncogenic functions in viral and non-viral lymphoid tumors.

Objectives

Obese women are at increased risk of cervical cancer, partly due to missed detection of cervical precancers during routine cervical cancer screening. We administered a clinician survey to better understand specific challenges and identify potential solutions to performing cervical cancer screening and management in obese women.

Materials and methods

We administered a web-based survey to 2,319 members of the American Society of Colposcopy and Cervical Pathology including questions related to challenges associated with cervical sampling and visualization in obese compared with normal weight women and potential strategies for improvement. We summarized providers' responses using descriptive statistics and used Fisher exact tests to evaluate associations between provider characteristics and challenges with cervical sampling, visualization, and biopsy.

Results

Of the 240 providers that completed the survey, 89% and 93% reported that cervical sampling and visualization are more challenging in obese women, respectively, whereas 80% reported that taking a biopsy was more challenging. Commonly reported barriers included vaginal prolapse, difficulty visualizing and accessing the cervix, and lack of long enough sampling devices and large enough speculums. Frequently used techniques to improve sampling and visualization included use of a condom or examination glove finger to sheath a speculum and using a tenaculum. Most providers identified training for cervical sampling and colposcopy in obese women as a learning gap, and only 8% reported receiving such training.

Conclusions

Cervical cancer screening and management are more challenging in obese compared with normal weight women. Major barriers to cervical sampling and visualization included lack of adequately sized equipment and lack of education and training.

The American Society for Colposcopy and Cervical Pathology (ASCCP) Colposcopy Standards recommendations address the role of colposcopy and directed biopsy for cervical cancer prevention in the United States (US). The recommendations were developed by an expert working group appointed by ASCCP's Board of Directors. An extensive literature review was conducted and supplemented by a systematic review and meta-analysis of unpublished data. In addition, a survey of practicing colposcopists was conducted to assess current colposcopy practice in the US. Recommendations were approved by the working group members, and the final revisions were made based on comments received from the public. The recommendations cover terminology, risk-based colposcopy, colposcopy procedures, and colposcopy adjuncts. The ASCCP Colposcopy Standards recommendations are an important step toward raising the standard of colposcopy services delivered to women in the US. Because cervical cancer screening programs are currently undergoing important changes that may affect colposcopy performance, updates to some of the current recommendations may be necessary in the future.

We report severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike ΔH69/V70 in multiple independent lineages, often occurring after acquisition of receptor binding motif replacements such as N439K and Y453F, known to increase binding affinity to the ACE2 receptor and confer antibody escape. In vitro, we show that, although ΔH69/V70 itself is not an antibody evasion mechanism, it increases infectivity associated with enhanced incorporation of cleaved spike into virions. ΔH69/V70 is able to partially rescue infectivity of spike proteins that have acquired N439K and Y453F escape mutations by increased spike incorporation. In addition, replacement of the H69 and V70 residues in the Alpha variant B.1.1.7 spike (where ΔH69/V70 occurs naturally) impairs spike incorporation and entry efficiency of the B.1.1.7 spike pseudotyped virus. Alpha variant B.1.1.7 spike mediates faster kinetics of cell-cell fusion than wild-type Wuhan-1 D614G, dependent on ΔH69/V70. Therefore, as ΔH69/V70 compensates for immune escape mutations that impair infectivity, continued surveillance for deletions with functional effects is warranted.

The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for virus infection through the engagement of the human ACE2 protein¹ and is a major antibody target. Here we show that chronic infection with SARS-CoV-2 leads to viral evolution and reduced sensitivity to neutralizing antibodies in an immunosuppressed individual treated with convalescent plasma, by generating whole-genome ultra-deep sequences for 23 time points that span 101 days and using in vitro techniques to characterize the mutations revealed by sequencing. There was little change in the overall structure of the viral population after two courses of remdesivir during the first 57 days. However, after convalescent plasma therapy, we observed large, dynamic shifts in the viral population, with the emergence of a dominant viral strain that contained a substitution (D796H) in the S2 subunit and a deletion (ΔH69/ΔV70) in the S1 N-terminal domain of the spike protein. As passively transferred serum antibodies diminished, viruses with the escape genotype were reduced in frequency, before returning during a final, unsuccessful course of convalescent plasma treatment. In vitro, the spike double mutant bearing both ΔH69/ΔV70 and D796H conferred modestly decreased sensitivity to convalescent plasma, while maintaining infectivity levels that were similar to the wild-type virus.The spike substitution mutant D796H appeared to be the main contributor to the decreased susceptibility to neutralizing antibodies, but this mutation resulted in an infectivity defect. The spike deletion mutant ΔH69/ΔV70 had a twofold higher level of infectivity than wild-type SARS-CoV-2, possibly compensating for the reduced infectivity of the D796H mutation. These data reveal strong selection on SARS-CoV-2 during convalescent plasma therapy, which is associated with the emergence of viral variants that show evidence of reduced susceptibility to neutralizing antibodies in immunosuppressed individuals.