Surgical closure of spinal cerebrospinal fluid leaks improves symptoms in patients with superficial siderosis.

BACKGROUND AND PURPOSE: Spinal cerebrospinal fluid (CSF) leaks may cause a myriad of symptoms, most common being orthostatic headache. In addition, ventral spinal CSF leaks are a possible etiology of superficial siderosis (SS), a rare condition characterized by hemosiderin deposits in the central nervous system (CNS). The classical presentation of SS involves ataxia, bilateral hearing loss, and myelopathy. Unfortunately, treatment options are scarce. This study was undertaken to evaluate whether microsurgical closure of CSF leaks can prevent further clinical deterioration or improve symptoms of SS. METHODS: This cohort study was conducted using data from a prospectively maintained database in two large spontaneous intracranial hypotension (SIH) referral centers in Germany and Switzerland of patients who meet the modified International Classification of Headache Disorders, 3rd edition criteria for SIH. Patients with spinal CSF leaks were screened for the presence of idiopathic infratentorial symmetric SS of the CNS. RESULTS: Twelve patients were included. The median latency between the onset of orthostatic headaches and symptoms attributed to SS was 9.5 years. After surgical closure of the underlying spinal CSF leak, symptoms attributed to SS improved in seven patients and remained stable in three. Patients who presented within 1 year after the onset of SS symptoms improved, but those who presented in 8-12 years did not improve. We could show a significant association between patients with spinal longitudinal extrathecal collections and SS. CONCLUSIONS: Long-standing untreated ventral spinal CSF leaks can lead to SS of the CNS, and microsurgical sealing of spinal CSF leaks might stop progression and improve symptoms in patients with SS in a time-dependent manner.

Targeting Stat3 signaling impairs the progression of bladder cancer in a mouse model.

Bladder cancer is the fourth most commonly diagnosed malignancy in men worldwide and has one of the highest recurrence rates of all cancers. This cancer type is unique because chronic inflammation caused by Schistosoma haematobium can cause bladder cancer, while inflammation induced by Bacillus Calmette Guerin is the therapeutic cornerstone for this cancer type. Activation of proinflammatory IL-6/Stat3 axis promotes the development of different cancers by acting on cancer cells as well as by modulating cancer microenvironment. Using a genetic and pharmacological approach in a mouse model, we demonstrated the importance of IL-6 and Stat3 signaling in bladder cancer. Our findings show that pharmacological inhibition of Stat3 with WP1066 effectively delays progression and invasiveness of bladder cancer in N-butyl-N-(4-hydroxybutyl) nitrosamine-induced mouse model. Moreover, either IL-6 blockade or Stat3 inhibition sensitized bladder cancer to anti-PD-L1 immune therapy. Taken together, our study demonstrates an important role of IL-6/Stat3 signaling in bladder cancer and creates a rationale for testing the therapeutic potential of Stat3 inhibitors in human MIBC both alone or in combination with anti-PD-L1 and anti-IL-6 therapy.

The dynamics of the inflammatory response during BBN-induced bladder carcinogenesis in mice.

BACKGROUND: Bladder cancer (BC) is the most common malignant disease of the urinary tract. Recurrent high grade non muscle invasive BC carries a serious risk for progression and subsequent metastases. The most common preclinical mouse model for bladder cancer relies on administration of N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) to mice. BBN-induced tumors in mice recapitulate the histology of human BC and were characterized with an overexpression of markers typical for basal-like cancer subtype in addition to a high mutational burden with frequent mutations in Trp53, similar to human muscle invasive BC. METHODS: Bladder cancer was induced in C57BL/6J male mice by administering the BBN in the drinking water. A thorough histopathological analysis of bladder specimen during and post BBN treatment was performed at 2, 4, 16, 20 and 25 weeks. RNA sequencing and qPCR was performed to assess the levels of expression of immunologically relevant genes at 2 weeks and 20 weeks during and post BBN treatment. RESULTS: We characterized the dynamics of the inflammatory response in the BBN-induced BC in mice. The treatment with BBN had gradually induced a robust inflammation in the first 2 weeks of administration, however, the inflammatory response was progressively silenced in the following weeks of the treatment, until the progression of the primary carcinoma. Tumors at 20 weeks were characterized with a marked upregulation of IL18 when compared to premalignant inflammatory response at 2 weeks. In accordance with this, we observed an increase in expression of IFNγ-responsive genes coupled to a pronounced lymphocytic infiltrate during the early stages of malignant transformation in bladder. Similar to human basal-like BC, BBN-induced murine tumors displayed an upregulated expression of immunoinhibitory molecules such as CTLA-4, PD-L1, and IDO1 which can lead to cytotoxic resistance and tumor escape. CONCLUSIONS: Despite the recent advances in bladder cancer therapy which include the use of checkpoint inhibitors, the treatment options for patients with locally advanced and metastatic BC remain limited. BBN-induced BC in mice displays an immunological profile which shares similarities with human MIBC thus representing an optimal model for preclinical studies on immunomodulation in management of BC.