Gefitinib Inhibits Rifampicin-Induced CYP3A4 Gene Expression in Human Hepatocytes.

During multidrug combination chemotherapy, activation of the nuclear receptor and the transcription factor human pregnane xenobiotic receptor (hPXR) has been shown to play a role in the development of chemoresistance. Mechanistically, this could occur due to the cancer drug activation of hPXR and the subsequent upregulation of hPXR target genes such as the drug metabolism enzyme, cytochrome P450 3A4 (CYP3A4). In the context of hPXR-mediated drug resistance, hPXR antagonists would be useful adjuncts to PXR-activating chemotherapy. However, there are currently no clinically approved hPXR antagonists in the market. Gefitinib (GEF), a tyrosine kinase inhibitor used for the treatment of advanced non-small-cell lung cancer and effectively used in combinational chemotherapy treatments, is a promising candidate owing to its hPXR ligand-like features. We, therefore, investigated whether GEF would act as an hPXR antagonist when combined with a known hPXR agonist, rifampicin (RIF). At therapeutically relevant concentrations, GEF successfully inhibited the RIF-induced upregulation of endogenous CYP3A4 gene expression in human primary hepatocytes and human hepatocells. Additionally, GEF inhibited the RIF induction of hPXR-mediated CYP3A4 promoter activity in HepG2 human liver carcinoma cells. The computational modeling of molecular docking predicted that GEF could bind to multiple sites on hPXR including the ligand-binding pocket, allowing for potential as a direct antagonist as well as an allosteric inhibitor. Indeed, GEF bound to the ligand-binding domain of the hPXR in cell-free assays, suggesting that GEF directly interacts with the hPXR. Taken together, our results suggest that GEF, at its clinically relevant therapeutic concentration, can antagonize the hPXR agonist-induced CYP3A4 gene expression in human hepatocytes. Thus, GEF could be a potential candidate for use in combinational chemotherapies to combat hPXR agonist-induced chemoresistance. Further studies are warranted to determine whether GEF has sufficient hPXR inhibitor abilities to overcome the hPXR agonist-induced chemoresistance.

A Telemedicine Buprenorphine Clinic to Serve New York City: Initial Evaluation of the NYC Public Hospital System's Initiative to Expand Treatment Access During the COVID-19 Pandemic.

OBJECTIVES: The purpose of this study was to assess the feasibility and clinical impact of telemedicine-based opioid treatment with buprenorphine-naloxone following the Coronavirus disease 2019 pandemic. METHODS: Participants included in this retrospective analysis consisted of adult New York City residents with opioid use disorder eligible for enrollment in the NYC Health+Hospitals Virtual Buprenorphine Clinic between March and May 2020 (n = 78). Follow-up data were comprised of rates of retention in treatment at 2 months, referrals to community treatment, and induction-related events. RESULTS: During the initial 9 weeks of clinic operations, the clinic inducted 78 patients on to buprenorphine-naloxone and completed 252 visits. Patient referrals included non-NYC Health + Hospitals (n = 22, 28.2%) and NYC Health + Hospitals healthcare providers (n = 17, 21.8%), homeless shelter staff (n = 13, 16.7%), and the NYC Health + Hospitals jail reentry program in Rikers Island (n = 11, 14.1%). At 8 weeks, 42 patients remained in care (53.8%), 21 were referred to a community treatment program (26.9%), and 15 were lost to follow-up (19.2%). No patients were terminated from care due to disruptive behavior or suspicions of diversion or misuse of Buprenorphine. Adverse clinical outcomes were uncommon and included persistent withdrawal symptoms (n = 8, 4.3%) and one nonfatal opioid overdose (0.5%). CONCLUSIONS: Telemedicine-based opioid treatment and unobserved home induction on buprenorphine-naloxone offers a safe and feasible approach to expand the reach of opioid use disorder treatment, primary care, and behavioral health for a highly vulnerable urban population during an unprecedented natural disaster.

Reproductive and sexual health knowledge, experiences, and milestones in young adults with life-long HIV.

Reproductive and sexual health outcomes of adults with perinatal human immunodeficiency virus (PHIV) have not been well-characterized. This prospective cross-sectional study of 35 adult persons living with HIV (PLWH) from early life and 20 matched HIV-negative controls assessed quality of life, depressive symptoms, HIV transmission knowledge, and sexual/reproductive behaviors through self-report questionnaires. PLWH scored significantly worse than controls on depressive symptoms (p = 0.04) and two of six quality of life domains (p = 0.03, p = 0.0002). In contrast, PLWH scored significantly higher on transmission knowledge in the context of family planning (p = 0.002). PLWH were more likely to learn about sex from healthcare providers (p = 0.002) and were more confident in their sexual/reproductive health knowledge (p < 0.05). Both groups reported inconsistent condom use, but PLWH were more likely to have planned pregnancies (p = 0.005) and to share pregnancy planning with their partners (p < 0.05). Despite the challenges of living with a chronic stigmatized condition, adults with PHIV were knowledgeable about HIV transmission and family planning and demonstrated sexual practices and reproductive outcomes similar to age-matched controls. However, sub-optimal rates of viral suppression, inconsistent condom use, and the psychosocial impact of living with HIV continue to require the attention of healthcare provides for young adults with PHIV.

Long-term changes in hepatic fibrosis following hepatitis C viral clearance in patients with and without HIV.

BACKGROUND: While acute changes in hepatic fibrosis are recognized shortly after achieving sustained virological response (SVR) using direct-acting antiviral therapies, long-term outcomes for the growing population of successfully treated patients with HCV remain uncertain. The aim of this study is to characterize long-term changes in fibrosis following SVR in patients with and without HIV and to identify potential factors associated with progression or regression of fibrosis. METHODS: We completed a prospective longitudinal study of 162 subjects with HCV (34% HIV-coinfected) with pre-treatment fibrosis stage determined by liver biopsy and post-SVR transient elastography. Progression of fibrosis was defined as a two-stage or greater increase in fibrosis, while regression was defined as a two-stage or greater decrease at last follow-up. The median duration of follow-up was 4.1 years. RESULTS: Fibrosis progression occurred in 4% of subjects while regression occurred in 7% and 89% were stable and did not differ by HIV coinfection. Fibrosis progression was associated with increased body mass index (BMI), hepatic steatosis and smoking pack-years. In a multivariable logistic regression, HIV coinfection (P=0.009), lower steatosis score (P<0.05) and lower smoking pack-years (P=0.0007) were associated with a lower fibrosis score at last follow-up. CONCLUSIONS: We identify potentially important relationships between BMI, hepatic steatosis and smoking, and changes in hepatic fibrosis post-SVR in patients with and without HIV coinfection. Attention to modifiable risk factors such as body weight and smoking may reduce the risk of liver disease progression in the growing population of successfully treated chronic HCV patients.

Testosterone in Men With Chronic Hepatitis C Infection and After Hepatitis C Viral Clearance.

BACKGROUND: Hepatitis C virus (HCV) and hepatic dysfunction are associated with low total and free testosterone (TT and FT) and high sex hormone-binding globulin (SHBG). However, little is known about changes in testosterone following successful HCV treatment. METHODS: We evaluated testosterone levels and the prevalence of low testosterone in a cohort of 327 men with chronic HCV infection (human immunodeficiency virus [HIV] coinfection = 150) and in a subset of 85 men with testosterone levels obtained pre-HCV treatment and after sustained virologic response (SVR). Median follow-up was 36 months. RESULTS: Participants with active HCV at baseline had higher TT (P < .0001) and SHBG (P < .0001) compared with participants who had achieved SVR, whereas FT did not differ. Low TT (<10.4 nmol/L) was more prevalent in participants with SVR compared with active HCV (P = .002); however, low FT (<0.1735 nmol/L) was common (50% active HCV, 43% SVR) and did not different between groups. For participants with longitudinal determinations, TT and SHBG decreased significantly (P < .0001) while FT remained unchanged post-SVR. Low FT persisted after SVR (pre-treatment 58%, post-SVR 54%, P = .72). HIV status and change in aspartate aminotrasferase-to-platelet ratio were significant independent predictors of change in FT following SVR. CONCLUSIONS: During active HCV infection, testosterone deficiency may be masked due to elevated SHBG. Despite improvements in SHBG following SVR, low FT was common and persisted after HCV clearance, indicating the need for enhanced awareness and screening using estimates of FT following successful treatment of chronic HCV. CLINICAL TRIALS REGISTRATION: NCT01350648.

Belinostat, at Its Clinically Relevant Concentrations, Inhibits Rifampicin-Induced CYP3A4 and MDR1 Gene Expression.

Activation of human pregnane X receptor (hPXR) has been associated with induction of chemoresistance. It has been proposed that such chemoresistance via cytochrome P450/drug transporters can be reversed with the use of antagonists that specifically abrogate agonist-mediated hPXR activation. Unfortunately, proposed antagonists lack the specificity and appropriate pharmacological characteristics that allow these features to be active in the clinic. We propose that, ideally, an hPXR antagonist would be a cancer drug itself that is part of a "cancer drug cocktail" and effective as an hPXR antagonist at therapeutic concentrations. Belinostat (BEL), a histone deacetylase inhibitor approved for the treatment of relapsed/refractory peripheral T-cell lymphoma, and often used in combination with chemotherapy, is an attractive candidate based on its hPXR ligand-like features. We sought to determine whether these features of BEL might allow it to behave as an antagonist in combination chemotherapy regimens that include hPXR activators. BEL represses agonist-activated hPXR target gene expression at its therapeutic concentrations in human primary hepatocytes and LS174T human colon cancer cells. BEL repressed rifampicin-induced gene expression of CYP3A4 and multidrug resistance protein 1, as well as their respective protein activities. BEL decreased rifampicin-induced resistance to SN-38, the active metabolite of irinotecan, in LS174T cells. This finding indicates that BEL could suppress hPXR agonist-induced chemoresistance. BEL attenuated the agonist-induced steroid receptor coactivator-1 interaction with hPXR, and, together with molecular docking studies, the study suggests that BEL directly interacts with multiple sites on hPXR. Taken together, our results suggest that BEL, at its clinically relevant therapeutic concentration, can antagonize hPXR agonist-induced gene expression and chemoresistance.

Unanticipated increases in hepatic steatosis among human immunodeficiency virus patients receiving mineralocorticoid receptor antagonist eplerenone for non-alcoholic fatty liver disease.

BACKGROUND & AIMS: Non-alcoholic fatty liver disease is common in human immunodeficiency virus, but there are no approved therapies. The aim of this open-label proof-of-concept study was to determine the effect of the mineralocorticoid receptor antagonist eplerenone on hepatic fat in human immunodeficiency virus-infected patients with hepatic fat ≥5% by magnetic resonance spectroscopy. METHODS: Five subjects received eplerenone (25 mg daily × 1 week followed by 50 mg daily × 23 weeks). Laboratory tests were done at each visit, and the primary endpoint, change in hepatic fat content, was determined by MRI spectroscopy at baseline and week 24. RESULTS: The study was stopped early after observing unexpected significant increases in hepatic fat at week 24 (mean increase 13.0 ± 7.3%, P = .02). The increases in steatosis were accompanied by a tendency for transaminase values to decrease (alanine aminotransferase mean change -14 ± 16 IU/L, P = .14). There were no consistent changes in other metabolic parameters or blood pressure. Repeat assessment of hepatic steatosis 1-2 months after stopping study medication revealed improvements in steatosis towards baseline values. CONCLUSIONS: The unexpected observation of increased hepatic steatosis with the administration of eplerenone led to early termination of the investigation. While limited because of the small number of participants and the open-label design, this study provides data to suggest that mineralocorticoid receptor antagonism with eplerenone may not be an effective approach to treat hepatic steatosis in human immunodeficiency virus or the general population. Additional research is needed to determine the pathophysiological mechanism behind these unanticipated observations.

No Improvement in Hemoglobin A1c Following Hepatitis C Viral Clearance in Patients With and Without HIV.

Hepatitis C clearance with directly acting antivirals (DAAs) may be associated with acute decreases in hemoglobin A1c (HbA1c). We prospectively evaluated 251 chronic hepatitis C virus (HCV)-infected subjects (31% human immunodeficiency virus [HIV] positive) pre- and post-DAA therapy (median follow-up 28 months). Changes in HbA1c and glucose were minimal and did not differ by sustained virologic response (SVR), HIV, diabetes, or fibrosis. Following SVR, mean change in HbA1c was -0.022 ± 0.53%; however, total and low-density lipoprotein cholesterol increased significantly. Subjects with HIV had smaller transaminase reductions after SVR. Sustained benefits in glycemia were not identified following HCV clearance irrespective of HIV, diabetes, or fibrosis stage, whereas lipid alterations may warrant further investigation.

Dual-phase, surface tension-based fabrication method for generation of tumor millibeads.

Numerous methods have been developed for the fabrication of poly(ethylene glycol)-based hydrogel microstructures for drug-delivery and tissue-engineering applications. However, present methods focus on the fabrication of submicrometer scale hydrogel structures which have limited applications in creating larger tissue constructs, especially in recreating cancer tissue microenvironments. We aimed to establish a platform where cancer cells can be cultured in a three-dimensional (3D) environment, which closely replicates the native cancer microenvironment and facilitates efficient testing of anticancer drugs. This study demonstrated a novel surface tension-based fabrication technique for the generation of millimeter-scale hydrogel beads using a liquid-liquid dual phase system. The "hydrogel millibeads" obtained by this method were larger than previously reported, highly uniform in shape and size with better ease of size control and a high degree of consistency and reproducibility between batches. In addition, human breast cancer cells were encapsulated within these hydrogel constructs to generate "tumor millibeads", which were subsequently maintained in long-term 3D culture. Microscopic visualization using fluorescence imaging and microstructure analysis showed the morphology and uniform distribution of the cells within the 3D matrix and arrangement of cells with the surrounding scaffold material. Cell viability analysis revealed the creation of a core region of dead cells surrounded by healthy, viable cell layers at the periphery following long-term culture. These observations closely matched with those of native and in vivo tumors. Based on these results, this study established a rapidly reproducible surface tension-based fabrication technique for making spherical hydrogel millibeads and demonstrated the potential of this method in creating engineered 3D tumor tissues. It is envisioned that the developed hydrogel millibead system will facilitate the formation of physiologically relevant in vitro tumor models which will closely simulate the native tumor microenvironmental conditions and could enable future high-throughput testing of different anticancer drugs in preclinical trials.