Kenneth Pienta

Once cancer has metastasized it remains incurable as a result of evolved resistance to nearly all systemic therapies. Our group has demonstrated that an endocycling cancer cell state is an underappreciated mechanism of therapeutic resistance in many cancer settings. Cells in this state uncouple DNA replication from cell division to obtain abnormally high genomic content and cell size (over 40x volume). Resulting polyploidy and cellular hypertrophy provide survival advantages such as elevated genomic content, higher oxidative buffer capacity, increased autophagy, and heightened resistance to chemotherapy. Endocycling cancer cells are induced by multiple different classes of chemotherapy and present in vivo at increased frequencies both in metastatic sites and following chemotherapy. We hypothesize elimination of this overlooked resistant cancer cell state is critical for sustained anticancer therapies …

Chemoresistance is a major cause of treatment failure in many cancers. However, the life cycle of cancer cells as they respond to and survive environmental and therapeutic stress is understudied. In this study, we utilized a microfluidic device to induce the development of doxorubicin-resistant (DOXR) cells from triple negative breast cancer (TNBC) cells within 11 days by generating gradients of DOX and medium. In vivo chemoresistant xenograft models, an unbiased genome-wide transcriptome analysis, and a patient data/tissue analysis all showed that chemoresistance arose from failed epigenetic control of the nuclear protein-1 (NUPR1)/histone deacetylase 11 (HDAC11) axis, and high NUPR1 expression correlated with poor clinical outcomes. These results suggest that the chip can rapidly induce resistant cells that increase tumor heterogeneity and chemoresistance, highlighting the need for further studies on the epigenetic control of the NUPR1/HDAC11 axis in TNBC.

mRNA‐based molecular subtypes have implications for bladder cancer prognosis and clinical benefit from certain therapies. Whether small extracellular vesicles (sEVs) can reflect bladder cancer molecular subtypes is unknown. We performed whole transcriptome RNA sequencing for formalin fixed paraffin embedded (FFPE) tumour tissues and sEVs separated from matched tissue explants, urine and plasma in patients with bladder cancer. sEVs were separated using size‐exclusion chromatography, and characterized by transmission electron microscopy, nano flow cytometry and western blots, respectively. High yield of sEVs were obtained using approximately 1 g of tissue, incubated with media for 30 min. FFPE tumour tissue and tumour tissue‐derived sEVs demonstrated good concordance in molecular subtype classification. All urinary sEVs were classified as luminal subtype, while all plasma sEVs were …

Therapy resistance is one of the most common underlying causes of poor prognosis in cancer patients, ultimately driving fatal outcome. We have previous demonstrated that following chemotherapeutic stress, a subset of cancer cells undergo a mitotic skip and enter an endocycle, causing whole-genome duplication without division. This endocycling cell state is resistant to cytotoxic therapies and thus is an actuator of therapy resistance. Cells in the endocycling state eventually undergo depolyploidization and repopulate the tumor, observed clinically as a recurrence. We also demonstrated that the minus-end directed motor protein KIFC1, a mediator of centrosome clustering, has higher expression in cells following treatment. Centrosome amplification (CA) involves aberrations in centrosome number, where cells have 3 centrosomes. Cells with extra centrosomes create a multi-polar spindle during mitosis, which …

INTRODUCTION AND OBJECTIVEFor men with non-obstructive azoospermia, no imaging exists to determine if sperm is present prior to testicular sperm extraction (TESE). The objective of this pilot study is to assess whether high-frequency ultrasound (HFUS), which can differentiate structures of less than 70 μm, is capable of distinguishing enlarged seminiferous tubules with spermatogenesis from sclerotic seminiferous tubules without spermatogenesis.METHODSA 29 MHz HFUS (ExactVu micro-ultrasound system) was performed on 3 adult male Sprague-Dawley rats (controls), 3 three-week at pups (prepuberal), and 3 bulsulfan-treated (20 mg/kg) adult male rats. Ultrasound imaging was additionally performed in 3 fertile male controls, 3 men with microTESE-negative non-obstructive azoospermia, 3 men with TESE-positive obstructive azoospermia. Conventional ultrasound was also performed for a fertile man …

Therapy resistance is responsible for 90% of cancer-related deaths. We identified a novel mechanism of therapy resistance in which cancer cells enter an endocycling cell state, undergoing repeated S and G phases without dividing. As a result, resistant endocycling cells are 40 times larger than mitotic cancer cell controls. Interestingly, we observed that these non-proliferative endocycling cells can eventually give rise to proliferative progeny weeks after chemotherapy is removed, modeling cancer recurrence. We hypothesize that this endocycling cancer cell state is a critical driver of therapy resistance and cancer lethality. We evaluated oxidative stress in endocycling cells that survived the days and weeks following chemotherapy treatment using DCF-DA staining. We found increased levels of reactive oxygen species (ROS) in endocycling prostate cancer cells compared to untreated mitotic cells when normalized …

Radiotracers that are approved by the Food and Drug Administration (FDA) for use in patients with PCa include carbon 11 (11C)-choline, fluorine 18 (18F)-sodium fluoride, 18F-fluciclovine (Axumin®, Blue Earth Diagnostics, Inc., Oxford, UK), gallium 68 (68Ga)-PSMA-11 (institutional use only in US), and 2-(3-{1-carboxy-5-[(6-18F-fluoropyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid (18F-DCFPyL; PYLARIFY®, Progenics Pharmaceuticals, Inc. North Billerica, MA; US only). should read:Radiotracers that are approved by the Food and Drug Administration (FDA) for use in patients with PCa include carbon 11 (11C)-choline, fluorine 18 (18F)-sodium fluoride, 18F-fluciclovine (Axumin®, Blue Earth Diagnostics, Inc., Oxford, UK), gallium 68 (68Ga)-PSMA-11, and 2-(3-{1-carboxy-5-[(6-18F-fluoropyridine-3-carbonyl)-

We utilize game-theoretic multi-population models of prostate cancer to show how a high-frequency treatment via adaptive therapy can significantly increase life expectancy while drastically reduce the necessary dosage of chemotherapeutic agents. Rather than pursuing an extended treatment regimen aimed at maximal tumor reduction, our approach focuses on stabilizing cancer size and effectively arresting cancer progression through extreme brief, concentrated treatment episodes interspersed with short resting intervals. Here we consider two distinct evolutionary scenarios: one in which drug-resistant cells are present from the beginning, and another in which the drug-resistant cells can spontaneously emerge through stress-induced mutagenesis. We present analytical estimations and justifications for high-frequency adaptive therapy, and provide proposals for how it can be implemented through open-loop …