Incidental discovery of metastatic renal cell carcinoma at the vaginal wall: A case report.

Metastasis of renal cell carcinoma (RCC) to the vaginal wall has rarely been reported in the literature. We present a case of a 48-year-old who was found to have a solitary RCC metastasis at the vaginal wall, five years following radical nephrectomy. This case is noteworthy because this late presentation is unique, with prior reports of synchronous metastasis or metastasis within two years of nephrectomy, highlighting the need to consider metastatic RCC to the vagina a possibility even many years after treatment.

Metastatic renal cell carcinoma in the bladder following complex partial nephrectomy: A case report.

Metastasis of renal cell carcinoma (RCC) to the bladder is rare. We present a case of a 74-year-old patient with a metachronous, solitary metastasis of RCC to the bladder twenty months after partial nephrectomy and JJ-stent placement for a complex renal tumor. The mechanism of RCC metastasis to the bladder remains controversial, and we believe this case adds support to the drop metastasis theory.

Lysosomal targetomics of ghr KO mice shows chaperone-mediated autophagy degrades nucleocytosolic acetyl-coA enzymes.

Mice deficient in GHR (growth hormone receptor; ghr KO) have a dramatic lifespan extension and elevated levels of hepatic chaperone-mediated autophagy (CMA). Using quantitative proteomics to identify protein changes in purified liver lysosomes and whole liver lysates, we provide evidence that elevated CMA in ghr KO mice downregulates proteins involved in ribosomal structure, translation initiation and elongation, and nucleocytosolic acetyl-coA production. Following up on these initial proteomics findings, we used a cell culture approach to show that CMA is necessary and sufficient to regulate the abundance of ACLY and ACSS2, the two enzymes that produce nucleocytosolic (but not mitochondrial) acetyl-coA. Inhibition of CMA in NIH3T3 cells has been shown to lead to aberrant accumulation of lipid droplets. We show that this lipid droplet phenotype is rescued by knocking down ACLY or ACSS2, suggesting that CMA regulates lipid droplet formation by controlling ACLY and ACSS2. This evidence leads to a model of how constitutive activation of CMA can shape specific metabolic pathways in long-lived endocrine mutant mice.Abbreviations: CMA: chaperone-mediated autophagy; DIA: data-independent acquisition; ghr KO: growth hormone receptor knockout; GO: gene ontology; I-WAT: inguinal white adipose tissue; KFERQ: a consensus sequence resembling Lys-Phe-Glu-Arg-Gln; LAMP2A: lysosomal-associated membrane protein 2A; LC3-I: non-lipidated MAP1LC3; LC3-II: lipidated MAP1LC3; PBS: phosphate-buffered saline; PI3K: phosphoinositide 3-kinase.

Long-lived mice with reduced growth hormone signaling have a constitutive upregulation of hepatic chaperone-mediated autophagy.

Chaperone-mediated autophagy (CMA) is the most selective form of lysosomal proteolysis. CMA modulates proteomic organization through selective protein degradation, with targets including metabolic enzymes, cell growth regulators, and neurodegeneration-related proteins. CMA activity is low in ad libitum-fed rodents but is increased by prolonged fasting. AKT negatively regulates CMA at the lysosomal membrane by phosphorylating and inhibiting the CMA regulator GFAP. We have previously reported that long-lived Pou1f1/Pit1 mutant (Snell) mice and ghr (growth hormone receptor) knockout mice (ghr KO) have lower AKT activity when fed compared to littermate controls, suggesting the hypothesis that these mice have increased baseline CMA activity. Here, we report that liver lysosomes from fed Snell dwarf mice and ghr KO mice have decreased GFAP phosphorylation and increased CMA substrate uptake activity. Liver lysosomes isolated from fed Snell dwarf mice and ghr KO mice injected with the protease inhibitor leupeptin had increased accumulation of endogenous CMA substrates, compared to littermate controls, suggesting an increase in CMA in vivo. Mice with liver-specific ablation of GH (growth hormone) signaling did not have increased liver CMA, suggesting that a signaling effect resulting from a loss of growth hormone in another tissue causes enhanced CMA in Snell dwarf and ghr KO mice. Finally, we find Snell dwarf mice have decreased protein levels (in liver and kidney) of CIP2A, a well-characterized CMA target protein, without an associated change in Cip2a mRNA. Collectively, these data suggest that CMA is enhanced downstream of an endocrine change resulting from whole-body ablation of GH signaling.Abbreviations: CMA: chaperone-mediated autophagy; GH: growth hormone; ghr KO: growth hormone receptor knockout; LAMP2A: splice variant 1 of Lamp2 transcript; LC3-I: non-lipidated MAP1LC3; LC3-II: lipidated MAP1LC3; Li-ghr KO: liver-specific ghr knockout; MA: macroautophagy; MTORC1: mechanistic target of rapamycin kinase complex 1; MTORC2: mechanistic target of rapamycin kinase complex 2; PBS: phosphate-buffered saline.

Inhibition of class I PI3K enhances chaperone-mediated autophagy.

Chaperone-mediated autophagy (CMA) is the most selective form of lysosomal proteolysis, where individual peptides, recognized by a consensus motif, are translocated directly across the lysosomal membrane. CMA regulates the abundance of many disease-related proteins, with causative roles in neoplasia, neurodegeneration, hepatosteatosis, and other pathologies relevant to human health and aging. At the lysosomal membrane, CMA is inhibited by Akt-dependent phosphorylation of the CMA regulator GFAP. The INS-PI3K-PDPK1 pathway regulates Akt, but its role in CMA is unclear. Here, we report that inhibition of class I PI3K or PDPK1 activates CMA. In contrast, selective inhibition of class III PI3Ks does not activate CMA. Isolated liver lysosomes from mice treated with either of two orally bioavailable class I PI3K inhibitors, pictilisib or buparlisib, display elevated CMA activity, and decreased phosphorylation of lysosomal GFAP, with no change in macroautophagy. The findings of this study represent an important first step in repurposing class I PI3K inhibitors to modulate CMA in vivo.