Kristen V. Adams

Stromal cell extracellular vesicular cargo mediated regulation of breast cancer cell metastasis via ubiquitin conjugating enzyme E2 N pathway

Mesenchymal stromal cells (hMSCs) have been used to understand the stromal cell properties in solid tumors because of their ablity to differentiate into most cell types. We investigated the role of EVs from hMSCs (hMSC-EVs) in breast cancer metastasis using MDA-MB-231 parental cell line and organotropic sub-lines. We demonstrated that hMSC-EVs significantly suppressed the metastatic potential of the parental cell line when compared to their organotropic sublines. hMSC-EVs induce dormancy in the parental cell line but not in their organotropic sub-lines and miR-205 and miR-31 from EV cargo played a role. Further, Ubiquitin Conjugating Enzyme E2 N (UBE2N/Ubc13) - metastasis-regulating gene, is a target of these miRNAs and silencing of UBE2N/Ubc13 expression significantly suppressed migration, invasion, and proliferation of breast cancer cells. To summarize, hMSC-EVs support primary breast tumor progression but suppress the metastasis of breast cancer cells that are not organ-committed through the UBE2N/Ubc13 pathway and play a role in premetastic niche formation.

Pseudomonas aeruginosa Protease IV Exacerbates Pneumococcal Pneumonia and Systemic Disease

S. pneumoniae remains the leading cause of bacterial pneumonia despite widespread use of pneumococcal vaccines, forcing the necessity for appropriate treatment to control pneumococcal infections. Coinfections involving S. pneumoniae with other bacterial pathogens threaten antibiotic treatment strategies and disease outcomes. Currently, there is not an effective treatment for alveolar-capillary barrier dysfunction that precedes bacteremia. An understanding of the dynamics of host-pathogen interactions during single and mixed pulmonary infections could elucidate proper treatment strategies needed to prevent or reduce invasive disease. Antibiotic treatment decreases bacterial burden in the lung but also increases acute pathology due to cytotoxins released via antibiotic-induced bacterial lysis. Therefore, targeted therapeutics that inhibit or counteract the effects of bacterial proteases and toxins are needed in order to limit pathology and disease progression. This study identifies the cooperative effect of PIV and Ply, products of separate lung pathogens that additively alter the lung environment and facilitate invasive disease. ABSTRACT Pneumonia is a pulmonary disease affecting people of all ages and is consistently a leading cause of childhood mortality and adult hospitalizations. Streptococcus pneumoniae and Pseudomonas aeruginosa are major lung pathogens commonly associated with community-acquired and nosocomial pneumonia. Additionally, mixed lung infections involving these bacterial pathogens are increasing in prevalence and are frequently more severe than single infections. The cooperative interactions of these two pathogens that impact pulmonary disease severity are understudied. A major secreted virulence factor of P. aeruginosa, protease IV (PIV), cleaves interleukin 22 (IL-22), a cytokine essential for maintaining innate mucosal defenses against extracellular pathogens. Here, we investigate the ability of PIV to augment the virulence of a pneumococcal strain with limited virulence, S. pneumoniae EF3030, in a C57BL/6 murine model of pneumonia. We demonstrate that pulmonary coinfection involving P. aeruginosa 103-29 and S. pneumoniae EF3030 results in pneumococcal bacteremia that is abrogated during pneumococcal coinfection with a PIV-deficient strain. Furthermore, intratracheal administration of exogenous PIV and EF3030 resulted in abundant immune cell infiltration into the lung with large abscess formation, as well as severe bacteremia leading to 100% mortality. Heat-inactivated PIV did not worsen pneumonia or reliably induce bacteremia, suggesting that the specific activity of PIV is required. Our studies also show that PIV depletes IL-22 in vivo. Moreover, PIV-mediated enhancement of pneumonia and disease severity was dependent on the expression of pneumolysin (Ply), a prominent virulence factor of S. pneumoniae. Altogether, we reveal that PIV and Ply additively potentiate pneumonia in a murine model of lung infection. IMPORTANCE S. pneumoniae remains the leading cause of bacterial pneumonia despite widespread use of pneumococcal vaccines, forcing the necessity for appropriate treatment to control pneumococcal infections. Coinfections involving S. pneumoniae with other bacterial pathogens threaten antibiotic treatment strategies and disease outcomes. Currently, there is not an effective treatment for alveolar-capillary barrier dysfunction that precedes bacteremia. An understanding of the dynamics of host-pathogen interactions during single and mixed pulmonary infections could elucidate proper treatment strategies needed to prevent or reduce invasive disease. Antibiotic treatment decreases bacterial burden in the lung but also increases acute pathology due to cytotoxins released via antibiotic-induced bacterial lysis. Therefore, targeted therapeutics that inhibit or counteract the effects of bacterial proteases and toxins are needed in order to limit pathology and disease progression. This study identifies the cooperative effect of PIV and Ply, products of separate lung pathogens that additively alter the lung environment and facilitate invasive disease.

Long-Lasting Androgen-Induced Cardiometabolic Effects in Polycystic Ovary Syndrome

Abstract Polycystic ovary syndrome (PCOS), the most common endocrine disorder in women of reproductive age, is characterized by androgen excess and ovarian dysfunction and presents with increased cardiometabolic risk factors such as obesity, insulin resistance, and elevated blood pressure (BP). We previously reported that administration of dihydrotestosterone (DHT) to female rats elicits cardiometabolic derangements similar to those found in women with PCOS. In this study, we tested the hypothesis that the DHT-mediated cardiometabolic derangements observed in PCOS are long lasting despite DHT withdrawal. Four-week-old female Sprague Dawley rats were treated with DHT (7.5 mg/90 days) or placebo for 6 months. DHT was discontinued (ex-DHT), and rats were followed for 6 additional months. After 6 months of DHT withdrawal, food intake, body weight, fat and lean mass, fasting plasma insulin, leptin, and adiponectin were elevated in ex-DHT rats. BP remained significantly elevated, and enalapril, an angiotensin-converting enzyme (ACE) inhibitor, normalized BP in ex-DHT rats. Expression of components of the intrarenal renin-angiotensin system was increased in ex-DHT rats. The cardiometabolic features found in ex-DHT rats were associated with lower plasma androgen levels but increased expression of renal and adipose tissue androgen receptors. In summary, androgen-induced cardiometabolic effects persisted after DHT withdrawal in a PCOS experimental model. Activation of intrarenal renin-angiotensin system plays a major role in the androgen-mediated increase in BP in ex-DHT. Upregulation of the renal and adipose tissue androgen receptor may explain the long-lasting effects of androgens. In clinical scenarios characterized by hyperandrogenemia in women, prompt normalization of androgen levels may be necessary to prevent their long-lasting cardiometabolic effects.

Fibrolamellar hepatocellular carcinoma in ascitic fluid: A case report with cytohistological correlation

The fibrolamellar variant of hepatocellular carcinoma (FL‐HCC) is distinguished from other hepatocellular carcinomas (HCC) by its unique clinical and pathological features. Cytological features of this tumor on fine needle aspiration have been described earlier. We report a rare case of a 17‐year‐old African American male with metastatic FL‐HCC, diagnosed by body fluid cytology. The patient presented with ascites and computed tomography (CT) scan revealed multiple omental masses and liver lesions. The fluid sample was obtained along with the omental biopsy and was found positive for metastatic fibrolamellar hepatocellular carcinoma. The fluid cytology showed atypical polygonal cells with enlarged nuclei, prominent nucleoli, and abundant granular cytoplasm. Cytomorphologic features of FL‐HCC presenting in body fluids have been rarely described before. This case enriches the cytopathology literature by providing awareness of this tumor presenting as metastasis in body fluids, especially in young individuals with liver lesions. Presence of a concurrent biopsy specimen provided cytohistological correlation, as it remains the gold standard for the accuracy and reliability of cytological diagnoses. Diagn. Cytopathol. 2016;44:757–760.