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A phase I/II trial of hydroxychloroquine in conjunction with radiation therapy and concurrent and adjuvant temozolomide in patients with newly diagnosed glioblastoma multiforme
Preclinical studies indicate autophagy inhibition with hydroxychloroquine (HCQ) can augment the efficacy of DNA-damaging therapy. The primary objective of this trial was to determine the maximum tolerated dose (MTD) and efficacy of HCQ in combination with radiation therapy (RT) and temozolomide (TMZ) for newly diagnosed glioblastoma (GB). A 3 + 3 phase I trial design followed by a noncomparative phase II study was conducted in GB patients after initial resection. Patients received HCQ (200 to 800 mg oral daily) with RT and concurrent and adjuvant TMZ. Quantitative electron microscopy and immunoblotting were used to assess changes in autophagic vacuoles (AVs) in peripheral blood mononuclear cells (PBMC). Population pharmacokinetic (PK) modeling enabled PK-pharmacodynamic correlations. Sixteen phase I subjects were evaluable for dose-limiting toxicities. At 800 mg HCQ/d, 3/3 subjects experienced Grade 3 and 4 neutropenia and thrombocytopenia, 1 with sepsis. HCQ 600 mg/d was found to be the MTD in this combination. The phase II cohort (n = 76) had a median survival of 15.6 mos with survival rates at 12, 18, and 24 mo of 70%, 36%, and 25%. PK analysis indicated dose-proportional exposure for HCQ. Significant therapy-associated increases in AV and LC3-II were observed in PBMC and correlated with higher HCQ exposure. These data establish that autophagy inhibition is achievable with HCQ, but dose-limiting toxicity prevented escalation to higher doses of HCQ. At HCQ 600 mg/d, autophagy inhibition was not consistently achieved in patients treated with this regimen, and no significant improvement in overall survival was observed. Therefore, a definitive test of the role of autophagy inhibition in the adjuvant setting for glioma patients awaits the development of lower-toxicity compounds that can achieve more consistent inhibition of autophagy than HCQ
Localization and expression of natriuretic peptide receptor subtype A and subtype C in rat parietal cells
Autophagy inhibitor Lys05 has single-agent antitumor activity and reproduces the phenotype of a genetic autophagy deficiency
Autophagy is a lysosome-dependent degradative process that protects cancer cells from multiple stresses. In preclinical models, autophagy inhibition with chloroquine (CQ) derivatives augments the efficacy of many anticancer therapies, but CQ has limited activity as a single agent. Clinical trials are underway combining anticancer agents with hydroxychloroquine (HCQ), but concentrations of HCQ required to inhibit autophagy are not consistently achievable in the clinic. We report the synthesis and characterization of bisaminoquinoline autophagy inhibitors that potently inhibit autophagy and impair tumor growth in vivo. The structural motifs that are necessary for improved autophagy inhibition compared with CQ include the presence of two aminoquinoline rings and a triamine linker and C-7 chlorine. The lead compound, Lys01, is a 10-fold more potent autophagy inhibitor than HCQ. Compared with HCQ, Lys05, a water-soluble salt of Lys01, more potently accumulates within and deacidifies the lysosome, resulting in impaired autophagy and tumor growth. At the highest dose administered, some mice develop Paneth cell dysfunction that resembles the intestinal phenotype ofmice and humanswith genetic defects in the autophagy gene ATG16L1, providing in vivo evidence that Lys05 targets autophagy. Unlike HCQ, significant single-agent antitumor activity is observed without toxicity in mice treated with lower doses of Lys05, establishing the therapeutic potential of this compound in cancer
Measurements of Tumor Cell Autophagy Predict Invasiveness, Resistance to Chemotherapy, and Survival in Melanoma
ALDH1A1 and HLTF modulate the activity of lysosomal autophagy inhibitors in cancer cells
ALDH1A1 and HLTF modulate the activity of lysosomal autophagy inhibitors in cancer cells
<p>Lysosomal autophagy inhibitors (LAI) such as hydroxychloroquine (HCQ) have significant activity in a subset of cancer cell lines. LAIs are being evaluated in cancer clinical trials, but genetic determinants of sensitivity to LAIs are unknown, making it difficult to predict which tumors would be most susceptible. Here we characterize differentially expressed genes in HCQ-sensitive (-S) and -resistant (-R) cancer cells. Notably, expression of canonical macroautophagy/autophagy genes was not associated with sensitivity to HCQ. Expression patterns of ALDH1A1 (aldehyde dehydrogenase 1 family member A1) and HLTF (helicase like transcription factor) identified HCQ-S (ALDH1A1<sub>high</sub> HLTF<sub>low</sub>; ALDH1A1<sub>low</sub> HLTF<sub>low</sub>) and HCQ-R (ALDH1A1<sub>low</sub> HLTF<sub>high</sub>) cells. ALDH1A1 overexpression was found to enhance LAI cell entry and cytotoxicity without directly affecting lysosome function or autophagic flux. Expression of HLTF allows repair of DNA damage caused by LAI-induced reactive oxygen species, leading to HCQ resistance. Sensitivity to HCQ is increased in cells where <i>HLTF</i> is silenced by promoter methylation. HLTF overexpression blunted the antitumor efficacy of chloroquine derivatives in vitro and in vivo. Analysis of tumor RNA sequencing data from >700 patients in the Cancer Genome Atlas identified cancers including colon cancer, renal cell carcinoma, and gastric cancers, that were enriched for the HCQ-S or HCQ-R signature. These results provide mechanistic insights into LAI efficacy, and guidance for LAI clinical development.</p
A phase I/II trial of hydroxychloroquine in conjunction with radiation therapy and concurrent and adjuvant temozolomide in patients with newly diagnosed glioblastoma multiforme
Genetic and Phenotypic Landscape of Peripartum Cardiomyopathy
BACKGROUND: Peripartum cardiomyopathy (PPCM) occurs in approximately 1:2000 deliveries in the US and worldwide. The genetic underpinnings of PPCM remain poorly defined. Approximately 10% of women with PPCM harbor truncating variants in TTN (TTNtvs). Whether mutations in other genes can predispose to PPCM is not known. It is also not known if the presence of TTNtvs predicts clinical presentation or outcomes. Nor is it known if the prevalence of TTNtvs differs in women with PPCM and preeclampsia, the strongest risk factor for PPCM. METHODS: Women with PPCM were retrospectively identified from several US and international academic centers, and clinical information and DNA samples were acquired. Next-generation sequencing was performed on 67 genes, including TTN, and evaluated for burden of truncating and missense variants. The impact of TTNtvs on severity of clinical presentation, and on clinical outcomes, was evaluated. RESULTS: 469 women met inclusion criteria. 10.4% of women with PPCM bore TTNtvs (Odds ration [OR]=9.4 compared with 1.2% in reference population; Bonferroni-corrected P [P*] =1.2x10(−46)). We additionally identified overrepresentation of truncating variants in FLNC (OR=24.8, P*=7.0x10(−8)), DSP (OR=14.9, P*=1.0x10(−8)), and BAG3 (OR=53.1, P*=0.02), genes not previously associated with PPCM. This profile is highly similar to that found in non-ischemic dilated cardiomyopathy (DCM). Women with TTNtvs had lower left ventricular ejection fraction (LVEF) on presentation than did women without TTNtvs (23.5% vs 29%, P=2.5x10(−4)), but did not differ significantly in timing of presentation after delivery, in prevalence of preeclampsia, or in rates of clinical recovery. CONCLUSIONS: This study provides the first extensive genetic and phenotypic landscape of PPCM, and demonstrates that predisposition to heart failure is an important risk factor for PPCM. The work reveals a degree of genetic similarity between PPCM and DCM, suggesting that gene-specific therapeutic approaches being developed for DCM may also apply to PPCM, and that approaches to genetic testing in PPCM should mirror those taken in DCM. Finally, the clarification of genotype/phenotype associations has important implications for genetic counseling