Medulloblastoma is the most common pediatric malignant brain tumor. Advances in molecular profiling have uncovered significant heterogeneity among medulloblastomas and led to the identification of four distinct subgroups (wingless [WNT], sonic hedgehog [SHH], group 3, and group 4) that represent distinct disease entities in both underlying biology and clinical characteristics. The rapidly expanding repertoire of tools to study developmental and cancer biology is providing a wealth of knowledge about these embryonal tumors and is continuously refining the understanding of this complex cancer. In this review, the history of discovery in medulloblastoma is discussed, setting a foundation to outline the current state of understanding of the molecular underpinnings of this disease, with a focus on genomic events that define the aforementioned subgroups and evolving areas of focus, such as the cell of origin of medulloblastoma and medulloblastoma subtypes. With these recent discoveries in mind, the current state of medulloblastoma treatment and clinical trials is reviewed, including a novel risk stratification system that accounts for the molecular biomarkers of patients with a high risk for refractory disease. Lastly, critical areas of focus for future basic science and clinical research on this disease are discussed, such as the complexities of medulloblastoma metastases and recurrence as well as the priorities and strategies to implement in future clinical trials.

Medulloblastoma (MB) is the most common malignant brain tumour in children but also rarely occur in adults. Sonic Hedgehog (SHH) driven MB is associated with aberrant activation of the SHH signalling pathway. SMO inhibitors, sonidegib and vismodegib, have been used as selective antagonist of the hedgehog pathway that acts by binding to SMO, and inhibits activation of the downstream hedgehog target genes. Several clinical trials investigating SMO inhibitors for the treatment of relapsed MB patients have been published.
We conducted a systemic review and meta-analysis among these Phase I and II clinical trials. The pooled effect of SMO inhibitors in relapsed MB were analysed using Reviewer Manager 5.3 software. The clinical efficacy of SMO inhibitors on SHH subtype of MB were measured by the objective response rate. The risk difference was obtained by comparing the ORR between SHH and non-SHH subtypes of MB.
The five studies all had clear criteria for patient recruitment, adequate follow-up time for endpoint assessment and clear definition of tumour responses. MB patients had good compliance in the trials. The pooled objective response rate (ORR) of SMO inhibitor was 37% and 0 against SHH-driven and other MBs. The pooled ORR of sonidegib was 55% among MBSHH and 0 among MBnon-SHH subgroup. Vismodegib also had no efficacy on non-SHH subtype of MB. The sonidegib against SHH-driven MB produced the ORR 1.87-fold higher than that of vismodegib (95%CI 1.23, 6.69). Among paediatric patients, the efficacy of sonidegib was 3.67-fold higher than vismodegib (p < 0.05). A total of 320 cases received SMO inhibitor therapy and 36 cases reported grade 3/4 dose-limiting toxicity (DLT). The rate of grade 3/4 DLT was similar between patients receiving vismodegib and sonidegib (11.6% vs. 11.2%).
Sonidegib and vismodegib were well tolerated and demonstrated anti-tumour activity in SHH-driven paediatric and adult MB by effectively inhibiting Hh signalling. These results support the ongoing clinical trials using SMO inhibitors in combination with conventional chemotherapies for the treatment of relapsed MBSHH.

Meningiomas are among the most common intracranial pathological conditions, accounting for 36% of intracranial lesions treated by neurosurgeons. Although the majority of these lesions are benign, the classical categorization of tumors by histological type or World Health Organization (WHO) grade has not fully captured the potential for meningioma progression and recurrence. Many targeted treatments have failed to generate a long-lasting effect on these tumors. Recently, several seminal studies evaluating the genomics of intracranial meningiomas have rapidly changed the understanding of the disease. The importance of NF2 (neurofibromin 2), TRAF7 (tumor necrosis factor [TNF] receptor-associated factor 7), KLF4 (Kruppel-like factor 4), AKT1, SMO (smoothened), PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha), and POLR2 (RNA polymerase II subunit A) demonstrates that there are at least 6 distinct mutational classes of meningiomas. In addition, 6 methylation classes of meningioma have been appreciated, enabling improved prediction of prognosis compared with traditional WHO grades. Genomic studies have shed light on the nature of recurrent meningioma, distinct intracranial locations and mutational patterns, and a potential embryonic cancer stem cell-like origin. However, despite these exciting findings, the clinical relevance of these findings remains elusive. The authors review the key findings from recent genomic studies in meningiomas, specifically focusing on how these findings relate to clinical insights for the practicing neurosurgeon.

Survival rates for patients with medulloblastoma have improved in the last decades but for those who relapse outcome is dismal and new approaches are needed. Emerging drugs have been tested in the last two decades within the context of phase I/II trials. In parallel, advances in genetic profiling have permitted to identify key molecular alterations for which new strategies are being developed. We performed a systematic review focused on the design and outcome of early-phase trials evaluating new agents in patients with relapsed medulloblastoma. PubMed, clinicaltrials.gov, and references from selected studies were screened to identify phase I/II studies with reported results between 2000 and 2015 including patients with medulloblastoma aged <18 years. A total of 718 studies were reviewed and 78 satisfied eligibility criteria. Of those, 69% were phase I; 31% phase II. Half evaluated conventional chemotherapeutics and 35% targeted agents. Overall, 662 patients with medulloblastoma/primitive neuroectodermal tumors were included. The study designs and the response assessments were heterogeneous, limiting the comparisons among trials and the correct identification of active drugs. Median (range) objective response rate (ORR) for patients with medulloblastoma in phase I/II studies was 0% (0-100) and 6.5% (0-50), respectively. Temozolomide containing regimens had a median ORR of 16.5% (0-100). Smoothened inhibitors trials had a median ORR of 8% (3-8). Novel drugs have shown limited activity against relapsed medulloblastoma. Temozolomide might serve as backbone for new combinations. Novel and more homogenous trial designs might facilitate the development of new drugs.

The Hedgehog inhibitors are promising alternative for patients with advanced basal cell carcinoma that are not amenable to radiotherapy or surgery. Sonidegib, also known as LDE225, is an orally available SMO antagonist that was recently approved by the US FDA for the treatment of patients with locally advanced basal cell carcinoma. This article will provide an overview of the pharmacology and pharmacokinetics of sonidegib and in-depth analysis of the BOLT trial with additional data from the 12-month update. The present challenges associated with Hedgehog inhibitors will also be discussed.

Hedgehog pathway inhibitors (HPIs) were made available by US Food and Drug Administration approval in 2012 for vismodegib and 2015 for sonidegib. Both target the Smoothened molecule and are indicated for locally advanced basal cell carcinoma (laBCC) and metastatic basal cell carcinoma (mBCC).
To evaluate clinical experience with HPIs, including efficacy and adverse effects.
We conducted a systematic review in concordance with the PRISMA guidelines of PubMed, the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and EMBASE, using search terms \"vismodegib,\" \"sonidegib,\" \"Erivedge,\" \"Odomza,\" \"basal cell carcinoma,\" and \"BCC.\"
We included clinical trials, retrospective medical record reviews, and prospective case series that used HPIs for the treatment of laBCC or mBCC in human subjects. Individual case reports and limited, retrospective case series were excluded from our review.
Data were extracted independently by 2 reviewers on a predesigned, standardized form.
The following data were recorded: number of patients with laBCC or mBCC, dose and frequency of drug administration, median duration of treatment, clearance and recurrence rates, and adverse effects.
Eleven vismodegib articles (published between 2009 and 2015) met criteria for inclusion, and 8 articles were able to be pooled for analysis. The 8 pooled articles included 744 total patients with 704 patients clinically evaluable. Sonidegib did not yield enough publications for a formal analysis. Objective response to vismodegib for laBCC had a weighted average of 64.7% (95% CI, 63.7%-65.6%); complete response averaged 31.1% (95% CI, 30.4%-31.8%). Objective response for mBCC was 33.6% (95% CI, 33.1%-34.2%); complete response averaged 3.9% (95% CI, 3.3%-4.4%). Median duration of therapy was 35.8 weeks (95% CI, 35.1-36.5 weeks).
In a systematic review of HPIs for laBCC and mBCC, vismodegib, but not sonidegib, had enough studies to warrant a pooled analysis. Vismodegib was identified to have a significant, consistent effect on the median duration of therapy of laBCC and mBCC. While mBCC responses are superior to any traditional approach, the response rate for laBCC might be considered in the context of other standard treatment options including surgery and radiation therapy.

BACKGROUND: The Hedgehog (Hh) signaling pathway has recently been reported to be associated with the prognosis of digestive system cancers. However, the results are inconsistent.
OBJECTIVE: This study aimed to investigate the association between Hh pathway components and survival outcomes in patients with digestive system cancers.
METHODS: We conducted a comprehensive retrieval in PubMed, EMBASE and Cochrane library for relevant literatures until May 1st, 2015. The pooled hazard ratios (HRs) for overall survival (OS) and disease-free survival (DFS) with 95% confidence intervals (CIs) were calculated to clarify the prognostic value of Hh pathway components, including Shh, Gli1, Gli2, Smo and Ptch1.
RESULTS: A total of 16 eligible articles with 3222 patients were included in the meta-analysis. Pooled HR suggested that over-expression of Shh and Gli1 were both associated with poor OS (HR = 1.87, 95% CI: 1.14-3.07 and HR = 1.96, 95% CI: 1.66-2.32, respectively) and DFS (HR = 2.37, 95% CI: 1.19-4.72 and HR = 2.18, 95% CI: 1.61-2.96, respectively). In addition, over-expression of Smo was associated with poor DFS (HR = 1.38, 95% CI: 1.08-1.75).
CONCLUSIONS: This study reveals that over-expressed Hh pathway components, including Shh, Gli1 and Smo, are associated with poor prognosis in digestive system cancer patients. Hh signaling pathway may become a potential therapeutic target in digestive system cancers.

Minor salivary gland carcinomas represent a heterogeneous group of tumors with broad variation in clinical appearance and histopathology. Clinical data of patients with small salivary gland malignancies were collected from the medical records. Tissue microarray was constructed to determine the expression pattern of 24 proteins in 35 patients with minor salivary gland carcinomas. The choice of markers was based on involvement in neoangiogenesis, cell-to-cell contact, cell-cycle regulation and carcinogenesis. Protein expression data were correlated to patients\' clinical data. Overexpression of patched (p = 0.046) and Smo (p = 0.032) was linked to a better overall survival and Glutathione S-transferase π overexpression was linked to prolonged disease-free survival (p = 0.005). Cox-1 (p = 0.035) and VEGFR2 (p = 0.009) were significantly linked to decreased survival for recurrent disease. Bcl-x (84 %), β-catenin (87 %) and Cox-2 (87 %) were significantly overexpressed in minor salivary gland carcinomas. We have shown that Smo resulted in a better overall survival, whereas Gstπ in improved disease-free survival. VEGFR2 was a prognostic factor for survival after recurrence in patients with minor salivary gland carcinomas. Cyclooxygenase inhibitors and anti-Wnt-1 antibodies might be a potential therapeutic option in an adjuvant setting or for patients with unresectable tumors of the minor salivary glands.

Basal cell nevus syndrome (BCNS), also referred to as nevoid basal cell carcinoma syndrome or Gorlin-Goltz syndrome, was first described by Gorlin and Goltz in 1960 as an autosomal dominant disorder characterized by the early appearance of multiple basal cell carcinomas (BCCs), keratocysts of the jaw, ectopic calcifications, palmar and plantar pits, and anomalies of the ocular, skeletal, and reproductive systems. The genesis of this cancer\'s etiology in relation to BCNS was unclear until a few years ago when molecular analysis studies suggested a relationship between BCC and the loss-of-function mutations of the patched gene (PTCH) found on chromosome arm 9q. PTCH inhibits signaling by the membrane protein Smoothened (Smo), and this inhibition is relieved by binding sonic hedgehog (SHH) to PTCH. We describe a patient with multiple BCCs associated with x-ray anomalies of BCNS and review the basis of the SHH signaling pathway and clinical aspects of BCNS.

BACKGROUND: The hedgehog (Hh) pathway is a developmental signaling pathway that plays a key role in directing cellular growth and tissue patterning during embryonic development. Dysregulation of Hh signaling has been linked to the development of a variety of human tumors, and numerous drug development programs in both academia and industry are actively exploring inhibitors of the pathway as anti-cancer agents.
METHODS: This review surveys the recent patent literature (2009 - 2012) for Hh pathway inhibitors as treatments for a variety of human malignancies.
CONCLUSIONS: To date, all of the pathway inhibitors that have entered clinical trials and the majority of compounds identified via high-throughput screens target smoothened (Smo), a transmembrane protein that is essential for pathway signaling. While these compounds have shown initial promise in preclinical and clinical trials, several mechanisms of resistance to Smo inhibitors have been identified. Even with this knowledge, the majority of small-molecule pathway inhibitors disclosed in the recent patent literature directly target Smo. The continued identification of Hh pathway inhibitors that function either upstream or downstream is warranted not only to combat these emerging resistance mechanisms, but also to help elucidate the various cellular mechanisms that control both normal and oncogenic pathway signaling.