Regulation of volume-regulated anion channels alters sensitivity to platinum chemotherapy.

Cisplatin-based chemotherapy is used across many common tumor types, but resistance reduces the likelihood of long-term survival. We previously found the puromycin-sensitive aminopeptidase, NPEPPS, as a druggable driver of cisplatin resistance in vitro and in vivo and in patient-derived organoids. Here, we present a general mechanism where NPEPPS interacts with the volume-regulated anion channels (VRACs) to control cisplatin import into cells and thus regulate cisplatin response across a range of cancer types.

Molecular biomarkers of progression in non-muscle-invasive bladder cancer - beyond conventional risk stratification.

The global incidence of bladder cancer is more than half a million diagnoses each year. Bladder cancer can be categorized into non-muscle-invasive bladder cancer (NMIBC), which accounts for ~75% of diagnoses, and muscle-invasive bladder cancer (MIBC). Up to 45% of patients with NMIBC develop disease progression to MIBC, which is associated with a poor outcome, highlighting a clinical need to identify these patients.

Specific quantification of inducible HIV-1 reservoir by RT-LAMP.

Background: Strategies toward HIV-1 cure aim to clear, inactivate, reduce, or immunologically control the virus from a pool of latently infected cells such that combination antiretroviral therapy (cART) can be safely interrupted. In order to assess the impact of any putative curative interventions on the size and inducibility of the latent HIV-1 reservoir, robust and scalable assays are needed to precisely quantify the frequency of infected cells containing inducible HIV-1.

Methods: We developed Specific Quantification of Inducible HIV-1 by RT-LAMP (SQuHIVLa), leveraging the high sensitivity and specificity of RT-LAMP, performed in a single reaction, to detect and quantify cells expressing tat/rev HIV-1 multiply spliced RNA (msRNA) upon activation.

A 3D organoid platform that supports liver-stage infection can be used to identify intrahepatic antimalarial drugs.

Malaria, a major public health burden, is caused by spp parasites that first replicate in the human liver to establish infection before spreading to erythrocytes. Liver-stage malaria research has remained challenging due to the lack of a clinically relevant and scalable model of the human liver. Here, we demonstrate that organoids derived from intrahepatic ductal cells differentiated into a hepatocyte-like fate can support the infection and intrahepatic maturation of .

NPEPPS Is a Druggable Driver of Platinum Resistance.

Unlabelled: There is an unmet need to improve the efficacy of platinum-based cancer chemotherapy, which is used in primary and metastatic settings in many cancer types. In bladder cancer, platinum-based chemotherapy leads to better outcomes in a subset of patients when used in the neoadjuvant setting or in combination with immunotherapy for advanced disease. Despite such promising results, extending the benefits of platinum drugs to a greater number of patients is highly desirable.

PCID2 dysregulates transcription and viral RNA processing to promote HIV-1 latency.

HIV-1 latency results from tightly regulated molecular processes that act at distinct steps of HIV-1 gene expression. Here, we characterize PCI domain-containing 2 (PCID2) protein, a subunit of the transcription and export complex 2 (TREX2) complex, to enforce transcriptional repression and post-transcriptional blocks to HIV-1 gene expression during latency. PCID2 bound the latent HIV-1 LTR (long terminal repeat) and repressed transcription initiation during latency.

Hepatitis C virus infects and perturbs liver stem cells.

The hepatitis C virus (HCV) causes liver disease, affecting millions. Even though we have effective antivirals that cure HCV, they cannot stop terminal liver disease. We used an adult stem cell-derived liver organoid system to understand how HCV infection leads to the progression of terminal liver disease.

The efficacy and tolerability of latency-reversing agents in reactivating the HIV-1 reservoir in clinical studies: a systematic review.

Introduction: Understanding the clinical potency of latency-reversing agents (LRAs) on the HIV-1 reservoir is useful to deploy future strategies. This systematic review evaluated the effects of LRAs in human intervention studies.

Methods: A literature search was performed using medical databases focusing on studies with adults living with HIV-1 receiving LRAs.

Non-muscle-invasive bladder cancer molecular subtypes predict differential response to intravesical Bacillus Calmette-Guérin.

The recommended treatment for patients with high-risk non-muscle-invasive bladder cancer (HR-NMIBC) is tumor resection followed by adjuvant Bacillus Calmette-Guérin (BCG) bladder instillations. However, only 50% of patients benefit from this therapy. If progression to advanced disease occurs, then patients must undergo a radical cystectomy with risks of substantial morbidity and poor clinical outcome.

The BAF complex inhibitor pyrimethamine reverses HIV-1 latency in people with HIV-1 on antiretroviral therapy.

Reactivation of the latent HIV-1 reservoir is a first step toward triggering reservoir decay. Here, we investigated the impact of the BAF complex inhibitor pyrimethamine on the reservoir of people living with HIV-1 (PLWH). Twenty-eight PLWH on suppressive antiretroviral therapy were randomized (1:1:1:1 ratio) to receive pyrimethamine, valproic acid, both, or no intervention for 14 days.

Production of Recombinant Hepatitis B virus (HBV) and Detection of HBV in Infected Human Liver Organoids.

The absence of long term, primary untransformed models that support hepatitis B virus (HBV) infection and replication have hampered HBV pre-clinical research, which was reflected in the absence of a curative therapy until recently. One of the limitations for HBV research has been the absence of high titer and pure recombinant HBV stocks, which, as we describe here, can be generated using simple, and reproducible protocols. In addition to infection of more conventional and liver model systems, recombinant high titer purified HBV stocks can also be used to efficiently infect differentiated human liver organoids, whose generation, maintenance, and infection is discussed in detail in a companion organoid protocol.

HibeRNAtion: HIV-1 RNA Metabolism and Viral Latency.

HIV-1 infection remains non-curative due to the latent reservoir, primarily a small pool of resting memory CD4+ T cells bearing replication-competent provirus. Pharmacological reversal of HIV-1 latency followed by intrinsic or extrinsic cell killing has been proposed as a promising strategy to target and eliminate HIV-1 viral reservoirs. Latency reversing agents have been extensively studied for their role in reactivating HIV-1 transcription , although no permanent reduction of the viral reservoir has been observed thus far.

DEAD-ly Affairs: The Roles of DEAD-Box Proteins on HIV-1 Viral RNA Metabolism.

In order to ensure viral gene expression, Human Immunodeficiency virus type-1 (HIV-1) recruits numerous host proteins that promote optimal RNA metabolism of the HIV-1 viral RNAs (vRNAs), such as the proteins of the DEAD-box family. The DEAD-box family of RNA helicases regulates multiple steps of RNA metabolism and processing, including transcription, splicing, nucleocytoplasmic export, trafficking, translation and turnover, mediated by their ATP-dependent RNA unwinding ability. In this review, we provide an overview of the functions and role of all DEAD-box family protein members thus far described to influence various aspects of HIV-1 vRNA metabolism.

Generation, Maintenance and HBV Infection of Human Liver Organoids.

Hepatitis B virus (HBV) infection represents a major public health problem infecting approximately 400 million people worldwide. Despite the availability of a preventive vaccine and anti-viral therapies, chronic HBV infection remains a major health issue because it increases the risk of developing liver cirrhosis and hepatocellular carcinoma (HCC). The lack of a relevant model for the study of the molecular mechanisms that drive HBV replication and latency, as well as HBV-related carcinogenesis, has been one of the major obstacles to the development of curative strategies.

A Two-Color Haploid Genetic Screen Identifies Novel Host Factors Involved in HIV-1 Latency.

To identify novel host factors as putative targets to reverse HIV-1 latency, we performed an insertional mutagenesis genetic screen in a latent HIV-1 infected pseudohaploid KBM7 cell line (Hap-Lat). Following mutagenesis, insertions were mapped to the genome, and bioinformatic analysis resulted in the identification of 69 candidate host genes involved in maintaining HIV-1 latency. A select set of candidate genes was functionally validated using short hairpin RNA (shRNA)-mediated depletion in latent HIV-1 infected J-Lat A2 and 11.

Application of human liver organoids as a patient-derived primary model for HBV infection and related hepatocellular carcinoma.

The molecular events that drive hepatitis B virus (HBV)-mediated transformation and tumorigenesis have remained largely unclear, due to the absence of a relevant primary model system. Here we propose the use of human liver organoids as a platform for modeling HBV infection and related tumorigenesis. We first describe a primary ex vivo HBV-infection model derived from healthy donor liver organoids after challenge with recombinant virus or HBV-infected patient serum.

Clinical stage drugs targeting inhibitor of apoptosis proteins purge episomal Hepatitis B viral genome in preclinical models.

A major unmet clinical need is a therapeutic capable of removing hepatitis B virus (HBV) genome from the liver of infected individuals to reduce their risk of developing liver cancer. A strategy to deliver such a therapy could utilize the ability to target and promote apoptosis of infected hepatocytes. Presently there is no clinically relevant strategy that has been shown to effectively remove persistent episomal covalently closed circular HBV DNA (cccDNA) from the nucleus of hepatocytes.

Evolution of organoid technology: Lessons learnt in Co-Culture systems from developmental biology.

In recent years, the development of 3D organoids has opened new avenues of investigation into development, physiology, and regenerative medicine. Organoid formation and the process of organogenesis share common developmental pathways; thus, our knowledge of developmental biology can help model the complexity of different organs to refine organoids into a more sophisticated platform. The developmental process is strongly dependent on complex networks and communication of cell-cell and cell-matrix interactions among different cell populations and their microenvironment, during embryogenesis.

3D human liver organoids: An in vitro platform to investigate HBV infection, replication and liver tumorigenesis.

Hepatitis B Virus (HBV) infection is a leading cause of chronic liver cirrhosis and hepatocellular carcinoma (HCC) with an estimated 400 million people infected worldwide. The precise molecular mechanisms underlying HBV replication and tumorigenesis have remained largely uncharacterized due to the lack of a primary cell model to study HBV, a virus that exhibits stringent host species and cell-type specificity. Organoid technology has recently emerged as a powerful tool to investigate human diseases in a primary 3D cell-culture system that maintains the organisation and functionality of the tissue of origin.

Inter-Laboratory Reproducibility of Inducible HIV-1 Reservoir Quantification by TILDA.

Substantial efforts to eliminate or reduce latent HIV-1 reservoirs are underway in clinical trials and have created a critical demand for sensitive, accurate, and reproducible tools to evaluate the efficacy of these strategies. Alternative reservoir quantification assays have been developed to circumvent limitations of the quantitative viral outgrowth assay. One such assay is induced limiting dilution assay (TILDA), which measures the frequency of CD4+ T cells harboring inducible latent HIV-1 provirus.