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Autophagy is a core molecular pathway for the preservation of cellular and organismal homeostasis. Pharmacological and genetic interventions impairing autophagy responses promote or aggravate disease in a plethora of experimental models. Consistently, mutations in autophagy‐related processes cause severe human pathologies. Here, we review and discuss preclinical data linking autophagy dysfunction to the pathogenesis of major human disorders including cancer as well as cardiovascular, neurodegenerative, metabolic, pulmonary, renal, infectious, musculoskeletal, and ocular disorders. [ABSTRACT FROM AUTHOR]

Background: Sentinel lymph node biopsy (SLNB) has not been studied for invasive melanomas treated with Mohs micrographic surgery using frozen‐section MART‐1 immunohistochemical stains (MMS‐IHC). The primary objective of this study was to assess the accuracy and compliance with National Comprehensive Cancer Network (NCCN) guidelines for SLNB in a cohort of patients who had invasive melanoma treated with MMS‐IHC. Methods: This retrospective cohort study included all patients who had primary, invasive, cutaneous melanomas treated with MMS‐IHC at a single academic center between March 2006 and April 2018. The primary outcomes were the rates of documenting discussion and performing SLNB in patients who were eligible based on NCCN guidelines. Secondary outcomes were the rate of identifying the sentinel lymph node and the percentage of positive lymph nodes. Results: In total, 667 primary, invasive, cutaneous melanomas (American Joint Committee on Cancer T1a‐T4b) were treated with MMS‐IHC. The median patient age was 69 years (range, 25‐101 years). Ninety‐two percent of tumors were located on specialty sites (head and/or neck, hands and/or feet, pretibial leg). Discussion of SLNB was documented for 162 of 176 (92%) SLNB‐eligible patients, including 127 of 127 (100%) who had melanomas with a Breslow depth >1 mm. SLNB was performed in 109 of 176 (62%) SLNB‐eligible patients, including 102 of 158 melanomas (65%) that met NCCN criteria to discuss and offer SLNB and 7 of 18 melanomas (39%) that met criteria to discuss and consider SLNB. The sentinel lymph node was successfully identified in 98 of 109 patients (90%) and was positive in 6 of those 98 patients (6%). Conclusions: Combining SLNB and MMS‐IHC allows full pathologic staging and confirmation of clear microscopic margins before reconstruction of specialty site invasive melanomas. SLNB can be performed accurately and in compliance with consensus guidelines in patients with melanoma using MMS‐IHC. Sentinel lymph node biopsy has not been studied for patients who have invasive melanomas treated with Mohs micrographic surgery using frozen‐section MART‐1 immunostains. Sentinel lymph node biopsy can be performed accurately and in compliance with consensus guidelines in these patients. [ABSTRACT FROM AUTHOR]

Aims: We evaluated the potential effect of sonidegib at an oral dose of 800 mg once daily (QD) on the pharmacokinetics (PK) of the probe drugs warfarin (CYP2C9) and bupropion (CYP2B6). Methods: This was a multicentre, open‐label study to evaluate the effect of sonidegib on the PK of the probe drugs warfarin and bupropion in patients with advanced solid tumours. Cohort 1 patients received a single warfarin 15‐mg dose on Day 1 of the run‐in period and on Cycle 2 Day 22 (C2D22) of sonidegib administration. Cohort 2 patients received a single bupropion 75‐mg dose on Day 1 of run‐in period and on C2D22 of sonidegib administration. Sonidegib 800 mg QD oral dosing began on Cycle 1 Day 1 of a 28‐day cycle after the run‐in period in both cohorts. Results: The geometric means ratios [90% confidence interval] for (S)‐warfarin with and without sonidegib were: area under the concentration–time curve from time 0 to infinity (AUCinf) 1.15 [1.07, 1.24] and maximum plasma concentration (Cmax) 0.88 [0.81, 0.97]; and for (R)‐warfarin were: AUCinf 1.10 [0.98, 1.24] and Cmax 0.93 [0.87, 1.0]. The geometric means ratios [90% confidence interval] of bupropion with and without sonidegib were: AUCinf 1.10 [0.99, 1.23] and Cmax 1.16 [0.95, 1.42]. Sonidegib 800 mg had a safety profile that was similar to that of lower dose sonidegib 200 mg and was unaffected by single doses of the probe drugs. Conclusions: Sonidegib dosed orally at 800 mg QD (higher than the Food and Drug Administration‐approved dose) did not impact the PK or pharmacodynamics of warfarin (CYP2C9 probe substrate) or the PK of bupropion (CYP2B6 probe substrate). [ABSTRACT FROM AUTHOR]

Background: Poly(adenosine diphosphate ribose) polymerase (PARP) inhibitors exhibit promising activity against ovarian cancers, but their efficacy can be limited by acquired drug resistance. This study explores the role of autophagy in regulating the sensitivity of ovarian cancer cells to PARP inhibitors.Methods: Induction of autophagy was detected by punctate LC3 fluorescence staining, LC3I to LC3II conversion on Western blot analysis, and electron microscopy. Enhanced growth inhibition and apoptosis were observed when PARP inhibitors were used with hydroxychloroquine, chloroquine (CQ), or LYS05 to block the hydrolysis of proteins and lipids in autophagosomes or with small interfering RNA against ATG5 or ATG7 to prevent the formation of autophagosomes. The preclinical efficacy of the combination of CQ and olaparib was evaluated with a patient-derived xenograft (PDX) and the OVCAR8 human ovarian cancer cell line.Results: Four PARP inhibitors (olaparib, niraparib, rucaparib, and talazoparib) induced autophagy in a panel of ovarian cancer cells. Inhibition of autophagy with CQ enhanced the sensitivity of ovarian cancer cells to PARP inhibitors. In vivo, olaparib and CQ produced additive growth inhibition in OVCAR8 xenografts and a PDX. Olaparib inhibited PARP activity, and this led to increased reactive oxygen species (ROS) and an accumulation of γ-H2AX. Inhibition of autophagy also increased ROS and γ-H2AX and enhanced the effect of olaparib on both entities. Treatment with olaparib increased phosphorylation of ATM and PTEN while decreasing the phosphorylation of AKT and mTOR and inducing autophagy.Conclusions: PARP inhibitor-induced autophagy provides an adaptive mechanism of resistance to PARP inhibitors in cancer cells with wild-type BRCA, and a combination of PARP inhibitors with CQ or other autophagy inhibitors could improve outcomes for patients with ovarian cancer. [ABSTRACT FROM AUTHOR]

Autophagy is a conserved, self-degradation system that is critical for maintaining cellular homeostasis during stress conditions. Dysregulated autophagy has implications in health and disease. Specifically, in cancer, autophagy plays a dichotomous role by inhibiting tumor initiation but supporting tumor progression. Early results from clinical trials that repurposed hydroxychloroquine for cancer have suggested that autophagy inhibition may be a promising approach for advanced cancers. In this review of the literature, the authors present fundamental advances in the biology of autophagy, approaches to targeting autophagy, the preclinical rationale and clinical experience with hydroxychloroquine in cancer clinical trials, the potential role of autophagy in tumor immunity, and recent developments in next-generation autophagy inhibitors that have clinical potential. Autophagy is a promising target for drug development in cancer. Cancer 2018. © 2018 American Cancer Society. [ABSTRACT FROM AUTHOR]

To determine the feasibility of liquid biopsy for monitoring of patients with advanced melanoma, cell-free DNA was extracted from plasma for 25 Stage III/IV patients, most (84.0%) having received previous therapy. DNA concentrations ranged from 0.6 to 390.0 ng/ml (median = 7.8 ng/ml) and were positively correlated with tumor burden as measured by imaging (Spearman rho = 0.5435, p = .0363). Using ultra-deep sequencing for a 61-gene panel, one or more mutations were detected in 12 of 25 samples (48.0%), and this proportion did not vary significantly for patients on or off therapy at the time of blood draw (52.9% and 37.5% respectively; p = .673). Sixteen mutations were detected in eight different genes, with the most frequent mutations detected in BRAF, NRAS, and KIT. Allele fractions ranged from 1.1% to 63.2% (median = 29.1%). Among patients with tissue next-generation sequencing, nine of 11 plasma mutations were also detected in matched tissue, for a concordance of 81.8%. [ABSTRACT FROM AUTHOR]

Lysosomes are membrane-bound intracellular organelles that receive macromolecules delivered by endocytosis, phagocytosis, and autophagy for degradation and recycling. Over the last decade, advances in lysosome research have established a broad role for the lysosome in the pathophysiology of disease. In this review, we highlight the recent discoveries in lysosome biology, with an emphasis on their implications for cancer therapy. We focus on targeting the lysosome in cancer by exploring lysosomal biogenesis and its role in the crosstalk between apoptosis and autophagy. We also discuss how lysosomal inhibition could emerge as a new therapeutic strategy to overcome drug resistance in cancer. [ABSTRACT FROM AUTHOR]

Resistance to BRAF inhibitors ( BRAFi) is one of the major challenges for targeted therapies for BRAF-mutant melanomas. However, little is known about the role of micro RNAs in conferring BRAFi resistance. Herein, we demonstrate that miR-200c expression is significantly reduced whereas miR-200c target genes including Bmi1, Zeb2, Tubb3, ABCG5, and MDR1 are significantly increased in melanomas that acquired BRAFi resistance compared to pretreatment tumor biopsies. Similar changes were observed in BRAFi-resistant melanoma cell lines. Overexpression of miR-200c or knock-down of Bmi1 in resistant melanoma cells restores their sensitivities to BRAFi, leading to deactivation of the PI3K/ AKT and MAPK signaling cascades, and acquisition of epithelial-mesenchymal transition-like phenotypes, including upregulation of E-cadherin, downregulation of N-cadherin, and ABCG5 and MDR1 expression. Conversely, knock-down of miR-200c or overexpression of Bmi1 in BRAFi-sensitive melanoma cells activates the PI3K/ AKT and MAPK pathways, upregulates N-cadherin, ABCG5, and MDR1 expression, and downregulates E-cadherin expression, leading to BRAFi resistance. Together, our data identify miR-200c as a critical signaling node in BRAFi-resistant melanomas impacting the MAPK and PI3K/ AKT pathways, suggesting miR-200c as a potential therapeutic target for overcoming acquired BRAFi resistance. [ABSTRACT FROM AUTHOR]

Autophagy plays a key role in the maintenance of cellular homeostasis. In healthy cells, such a homeostatic activity constitutes a robust barrier against malignant transformation. Accordingly, many oncoproteins inhibit, and several oncosuppressor proteins promote, autophagy. Moreover, autophagy is required for optimal anticancer immunosurveillance. In neoplastic cells, however, autophagic responses constitute a means to cope with intracellular and environmental stress, thus favoring tumor progression. This implies that at least in some cases, oncogenesis proceeds along with a temporary inhibition of autophagy or a gain of molecular functions that antagonize its oncosuppressive activity. Here, we discuss the differential impact of autophagy on distinct phases of tumorigenesis and the implications of this concept for the use of autophagy modulators in cancer therapy. [ABSTRACT FROM AUTHOR]

This study investigates the mechanism of action behind the long-term responses (12-16 months) of two BRAF WT melanoma patients to the AKT inhibitor MK-2206 in combination with paclitaxel and carboplatin. Although single agent MK-2206 inhibited phospho- AKT signaling, it did not impact in vitro melanoma growth or survival. The combination of MK-2206 with paclitaxel and carboplatin was cytotoxic in long-term colony formation and 3D spheroid assays, and induced autophagy. Autophagy was initially protective with autophagy inhibitors and deletion of ATG5 found to enhance cytotoxicity. Although prolonged autophagy induction (>6 days) led to caspase-dependent apoptosis, drug resistant clones still emerged. Autophagy inhibition enhanced the cell death response through reactive oxygen species and could be reversed by anti-oxidants. We demonstrate for the first time that AKT inhibition in combination with chemotherapy may have clinical activity in BRAF WT melanoma and show that an autophagy inhibitor may prevent resistance to these drugs. [ABSTRACT FROM AUTHOR]