Probes for INS

Obesity increases the risk of hepatocellular carcinoma (HCC), but precise identification and characterization of druggable oncogenic pathways that contribute to the progression of NAFLD to HCC, and hence to the increased incidence and aggressiveness of HCC in obese individuals is lacking. In this regard, we demonstrate that the Indian Hedgehog (Ihh) signaling pathway is upregulated in the fatty livers of mice consuming a high fat diet, and furthermore sustained in HCC tumors specifically within the context of a NAFLD microenvironment. Using a diet-induced mouse model of HCC wherein only obese mice develop HCC, targeted ablation of hepatocyte-secreted Ihh results in a decreased tumor burden and lower grade tumors. Ihh activation regulates the transdifferentiation of ciliated stellate cells and proliferation of Epcam+ ductal cells to promote fibrosis. Mechanistically, increased expression of hitherto uncharacterized effectors of Hh pathway, namely Myc and Tgf-β2 is critical to the observed physiology. This pro-tumorigenic response is driven by increased expression of Wnt5a to effect a poorly-differentiated and invasive tumor phenotype. Wnt5a secreted from activated stellate cells act on Ror2-expressing hepatocytes. We further demonstrate that Wnt5a expression is also elevated in poorly-differentiated HCC cells, suggesting that these ligands are also able to function in an autocrine positive feedback manner to sustain poorly-differentiated tumors. Taken together, our study provides a mechanistic understanding for how Ihh signaling promotes HCC tumorigenesis specifically in obese mice. We propose that therapeutic targeting of the Hh pathway offers benefit for patients with dietary / NAFLD-driven steatotic HCC.

Abstract
Background:

Although alcohol and tobacco use are known risk factors for development of squamous cell carcinoma in the head and neck, human papillomavirus (HPV) has been increasingly associated with this group of cancers. We describe the case of a married couple who presented with HPV-positive oropharynx squamous cell carcinoma within two months of each other.

Methods:

Tumor biopsies were positive for p16 and high-risk HPV in both patients. Sanger sequencing showed a nearly identical HPV16 strain in both patients. Both patients received chemoradiation, and one  patient also underwent transoral robotic tongue base resection with bilateral neck dissection.

Results:

Both patients showed no evidence of recurrent disease on follow-up PET imaging.

Conclusions:

New head and neck symptoms should be promptly evaluated in the partner of a patient with known HPV-positive oropharynx cancer. This case expands the limited current literature on concurrent presentation of HPV-positive oropharynx squamous cell carcinoma in couples. 

The striatum integrates motor behavior using a well-defined microcircuit whose individual components are independently affected in several neurological diseases. The glial cell line-derived neurotrophic factor (GDNF), synthesized by striatal interneurons, and Sonic hedgehog (Shh), produced by the dopaminergic neurons of the substantia nigra (DA SNpc), are both involved in the nigrostriatal maintenance but the reciprocal neurotrophic relationships among these neurons are only partially understood. To define the postnatal neurotrophic connections among fast-spiking GABAergic interneurons (FS), cholinergic interneurons (ACh), and DA SNpc, we used a genetically induced mouse model of postnatal DA SNpc neurodegeneration and separately eliminated Smoothened (Smo), the obligatory transducer of Shh signaling, in striatal interneurons. We show that FS postnatal survival relies on DA SNpc and is independent of Shh signaling. On the contrary, Shh signaling but not dopaminergic striatal innervation is required to maintain ACh in the postnatal striatum. ACh are required for DA SNpc survival in a GDNF-independent manner. These data demonstrate the existence of three parallel but interdependent neurotrophic relationships between SN and striatal interneurons, partially defined by Shh and GDNF. The definition of these new neurotrophic interactions opens the search for new molecules involved in the striatal modulatory circuit maintenance with potential therapeutic value.

Although hundreds of cytosolic or transmembrane molecules form the primary cilium, few secreted molecules are known to contribute to ciliogenesis. Here, homologous secreted metalloproteases ADAMTS9 and ADAMTS20 are identified as ciliogenesis regulators that act intracellularly. Secreted and furin-processed ADAMTS9 bound heparan sulfate and was internalized by LRP1, LRP2 and clathrin-mediated endocytosis to be gathered in Rab11 vesicles with a unique periciliary localization defined by super-resolution microscopy. CRISPR-Cas9 inactivation of ADAMTS9 impaired ciliogenesis in RPE-1 cells, which was restored by catalytically active ADAMTS9 or ADAMTS20 acting in trans, but not by their proteolytically inactive mutants. Their mutagenesis in mice impaired neural and yolk sac ciliogenesis, leading to morphogenetic anomalies resulting from impaired hedgehog signaling, which is transduced by primary cilia. In addition to their cognate extracellular proteolytic activity, ADAMTS9 and ADAMTS20 thus have an additional proteolytic role intracellularly, revealing an unexpected regulatory dimension in ciliogenesis.

Although human papillomavirus (HPV)-related oropharyngeal carcinomas (HPV-OPCs) are generally regarded as "poorly differentiated," they actually maintain a close resemblance to the lymphoepithelium of the tonsillar crypts from which they arise: they are basaloid, exhibit minimal keratinization, and are often permeated by lymphocytes. In rare cases, the presence of cilia in a primary HPV-OPC and their persistence in lymph node metastasis can confound the distinction between a benign and malignant process. Three cases of ciliated HPV-OPCs were identified from the archives of The Johns Hopkins Head and Neck Pathology consultation service. HPV status was determined using p16 immunohistochemistry and high-risk HPV in situ hybridization. All 3 patients presented with a cystic lymph node metastasis without a known primary carcinoma. One metastasis was originally diagnosed as a branchial cleft cyst only to regionally recur 7 years later. In 2 cases, a primary HPV-OPC was found in the tonsil. The carcinomas exhibited both nonkeratinizing squamous epithelium and cystic/microcystic spaces lined by ciliated columnar cells. Both the squamous and ciliated cells were HPV positive. This report draws attention to a novel variant of HPV-related head and neck cancer that exhibits ciliated columnar cells. This variant challenges prevailing notions that: (1) HPV-OPCs are uniformly poorly differentiated cancers; (2) cilia are an infallible feature of benignancy; and (3) presence of cilia is a reliable criterion for establishing branchial cleft origin when dealing with cystic lesions of the lateral neck.