Regulation of intercellular biomolecule transfer–driven tumor angiogenesis and responses to anticancer therapies

Intercellular biomolecule transfer (ICBT) between malignant and benign cells is a major driver of tumor growth, resistance to anticancer therapies, and therapy-triggered metastatic disease. Here we characterized cholesterol 25-hydroxylase (CH25H) as a key genetic suppressor of ICBT between malignant and endothelial cells (ECs) and of ICBT-driven angiopoietin-2–dependent activation of ECs, stimulation of intratumoral angiogenesis, and tumor growth. Human CH25H was downregulated in the ECs from patients with colorectal cancer and the low levels of stromal CH25H were associated with a poor disease outcome. Knockout of endothelial CH25H stimulated angiogenesis and tumor growth in mice. Pharmacologic inhibition of ICBT by reserpine compensated for CH25H loss, elicited angiostatic effects (alone or combined with sunitinib), augmented the therapeutic effect of radio-/chemotherapy, and prevented metastatic disease induced by these regimens. We propose inhibiting ICBT to improve the overall efficacy of anticancer therapies and limit their prometastatic side effects.     

Ultrasensitive Amplification Refractory Mutation System Real-Time PCR (ARMS RT-PCR) Assay for Detection of Minority Hepatitis B Virus-Resistant Strains in the Era of Personalized Medicine

Resistance to antiviral treatment for chronic hepatitis B virus (HBV) has been associated with mutations in the HBV polymerase region. This study aimed at developing an ultrasensitive method for quantifying viral populations with all major HBV resistance-associated mutations, combining the amplification refractory mutation system real-time PCR (ARMS RT-PCR) with a molecular beacon using a LightCycler. The discriminatory ability of this method, the ARMS RT-PCR with molecular beacon assay, was 0.01 to 0.25% for the different HBV resistance-associated mutations, as determined by laboratory-synthesized wild-type (WT) and mutant (Mut) target sequences. The assay showed 100% sensitivity for the detection of mutant variants A181V, T184A, and N236T in samples from 41 chronically HBV-infected patients under antiviral therapy who had developed resistance-associated mutations detected by direct PCR Sanger sequencing. The ratio of mutant to wild-type viral populations (the Mut/WT ratio) was >1% in 38 (63.3%) of 60 samples from chronically HBV-infected nucleos(t)ide analogue-naive patients; combinations of mutations were also detected in half of these samples. The ARMS RT-PCR with molecular beacon assay achieved high sensitivity and discriminatory ability compared to the gold standard of direct PCR Sanger sequencing in identifying resistant viral populations in chronically HBV-infected patients receiving antiviral therapy. Apart from the dominant clones, other quasispecies were also quantified. In samples from chronically HBV-infected nucleos(t)ide analogue-naive patients, the assay proved to be a useful tool in detecting minor variant populations before the initiation of the treatment. These observations need further evaluation with prospective studies before they can be implemented in daily practice.     

Differential in vitro pathogenicity of Photorhabdus bacterial species against two distinct insect cell lines

Understanding the mode of action of pathogenic bacteria through in vitro studies can provide additional insight into their infection strategies. Here we have characterized the effect of Photorhabdus luminescens and Photorhabdus asymbiotica on two distinct insect cell lines. We report that insect cell survival and metabolism as well as bacterial proliferation differ between infection with two Photorhabdus species. These findings reinforce the notion that P. luminescens and P. asymbiotica deploy diverse tactics to infect insect cells. This knowledge might lead to better appreciation of the interaction between pathogenic bacteria and different types of insect cells.     

Emerging treatment strategies for COVID-19 infection

Clinical and Experimental Medicine - The new type of coronavirus (COVID-19), SARS-CoV-2 originated from Wuhan, China and has led to a worldwide pandemic. COVID-19 is a novel emerging infectious...     

Posttraumatic Transdiaphragmatic Intercostal Hernia: Report of a Case and Review of the Literature

Intercostal hernias are rare, and usually occur following injuries of the thoracic wall. The scope of this report is to present a case of a 53-year-old obese patient that developed a transdiaphragmatic intercostal hernia. The patient presented with a palpable, sizeable, reducible mass in the right lateral thoracic wall, with evident bowel sounds in the area, 6 months after a motor-vehicle accident. On computed tomography (CT), the hernia sac contained part of the liver and part of the ascending colon. A surgical repair of the defect was performed, using a prosthetic patch. The patient''s postoperative course was uneventful and she remains recurrence free at 12 months after surgery. Intercostal hernias should be suspected following high-impact injuries of the thoracic wall, and CT scans will facilitate the diagnosis of intercostal hernia. We consider the surgical repair of the defect, with placement of a prosthetic mesh, as the treatment of choice to ensure a favorable outcome.Key words: Hernia, Transdiaphragmatic, Intercostal, Abdominal, MeshThe herniation of abdominal contents through the thoracic wall, as a result of the disruption of diaphragmatic and/or intercostal muscles, is an uncommon clinical entity.^1–3 This condition is usually reported to occur following penetrating or blunt injuries of the thoracic wall.⁴ However, there are several cases that have been described to be a consequence of a coughing–spell rib fracture, usually in patients with other predisposing factors such as chronic obstructive pulmonary disease, asthma, advanced age, or osteoporosis.^1,3,4The present report describes a case of a middle-aged obese patient that developed a transdiaphragmatic intercostal hernia involving the liver and the ascending colon 6 months after a traumatic incident. The underlying mechanism, the anatomical and diagnostic considerations, as well as the treatment options are also discussed.