Ca 2+ /Calmodulin Dependent Protein Kinase Kinase-2 (CaMKK2) promotes Protein Kinase G (PKG)-dependent actin cytoskeletal assembly to increase tumor metastasis.

Triple-negative breast cancers (TNBCs) tend to become highly invasive early during cancer development. Despite some successes in the initial treatment of patients diagnosed with early-stage localized TNBC, the rate of metastatic recurrence remains high with poor long-term survival outcomes. Here we show that elevated expression of the serine/threonine-kinase, Calcium/Calmodulin (CaM)-dependent protein kinase kinase-2 (CaMKK2), is highly correlated with tumor invasiveness. We determined that genetic disruption of CaMKK2 expression, or inhibition of its activity, disrupted spontaneous metastatic outgrowth from primary tumors in murine xenograft models of TNBC. High-grade serous ovarian cancer (HGSOC), a high-risk, poor-prognosis ovarian cancer subtype, shares many genetic features with TNBC, and importantly, CaMKK2 inhibition effectively blocked metastatic progression in a validated xenograft model of this disease. Probing the mechanistic links between CaMKK2 and metastasis we defined the elements of a new signaling pathway that impacts actin cytoskeletal dynamics in a manner which increases cell migration/invasion and metastasis. Notably, CaMKK2 increases the expression of the phosphodiesterase PDE1A which decreases the cGMP-dependent activity of protein kinase G1 (PKG1). This inhibition of PKG1 results in decreased phosphorylation of Vasodilator-Stimulated Phosphoprotein (VASP), which in its hypophosphorylated state binds to and regulates F-actin assembly to facilitate contraction/cell movement. Together, these data establish a targetable CaMKK2-PDE1A-PKG1-VASP signaling pathway that controls cancer cell motility and metastasis. Further, it credentials CaMKK2 as a therapeutic target that can be exploited in the discovery of agents for use in the neoadjuvant/adjuvant setting to restrict tumor invasiveness in patients diagnosed with early-stage TNBC or localized HGSOC.

Pilot phase results of a prospective, randomized controlled trial of narrowband ultraviolet B phototherapy in hospitalized COVID-19 patients.

COVID-19 morbidity and mortality are driven by poor immune regulation. Narrowband ultraviolet B (NB-UVB) phototherapy is standard of care in a number of immune-dysregulated diseases. To assess the efficacy of NB-UVB phototherapy for improving COVID-19 outcomes in high-risk, hospitalized, we developed the Adaptive Photo-Protection Trial. This is a multi-center, prospective, double-blinded, randomized, placebo-controlled trial. The pilot phase results are reported here. Consecutive patients admitted with a positive COVID-19 PCR were screened for eligibility. Enrolled subjects were computer randomized 1:1 to NB-UVB or placebo phototherapy. Subjects were treated daily with escalating doses on 27% of their body surface area for up to 8 consecutive days. Primary outcomes were safety and efficacy, defined as persistent or painful erythema and 28-day mortality. Comparisons were made via non-parametric exact tests. Patients in treatment (n = 15) and placebo (n = 15) arms had similar demographics. No adverse events occurred. Twenty eight-day mortality was 13.3% in treatment vs. 33.3% in placebo arms (p = 0.39). NB-UVB phototherapy in hospitalized COVID-19 patients was safe. Decreased mortality was observed in treated patients but this was statistically non-significant. Given its low-cost, scalability, and adjunctive nature, NB-UVB has the potential to improve COVID-19 outcomes. Continuation of this trial is warranted.

Naringenin Promotes Thermogenic Gene Expression in Human White Adipose Tissue.

OBJECTIVE: Naringenin, a citrus flavonoid, prevents diet-induced weight gain and improves glucose and lipid metabolism in rodents. There is evidence that naringenin activates brown fat and increases energy expenditure in mice, but little is known about its effects in humans. The goal of this study was to examine the effects of naringenin on energy expenditure in adipose tissue. METHODS: Human white adipocyte cultures (hADSC) and abdominal subcutaneous adipose tissue (pWAT) were treated with naringenin for 7 to 14 days. Expression (quantitative real-time polymerase chain reaction, immunoblotting) of candidate genes involved in thermogenesis and glucose metabolism was measured. Oxygen consumption rate was measured in hADSC using a Seahorse flux analyzer. RESULTS: In hADSC, naringenin increased expression of the genes associated with thermogenesis and fat oxidation, including uncoupling protein 1 and adipose triglyceride lipase, and key factors associated with insulin sensitivity, including glucose transporter type 4, adiponectin, and carbohydrate-responsive element-binding protein (P < 0.01). Similar responses were observed in pWAT. Basal, ATP-linked, maximal and reserve oxygen consumption rate increased in the naringenin-treated hADSC (P < 0.01). CONCLUSIONS: Naringenin increases energy expenditure in hADSC and stimulates expression of key enzymes involved in thermogenesis and insulin sensitivity in hADSC and pWAT. Naringenin may promote conversion of human white adipose tissue to a brown/beige phenotype.