Hedgehog pathway overexpression in pancreatic cancer is abrogated by new-generation taxoid SB-T-1216.

The Hedgehog pathway is one of the major driver pathways in pancreatic ductal adenocarcinoma. This study investigated prognostic importance of Hedgehog signaling pathway in pancreatic cancer patients who underwent a radical resection. Tumors and adjacent non-neoplastic pancreatic tissues were obtained from 45 patients with histologically verified pancreatic cancer. The effect of experimental taxane chemotherapy on the expression of Hedgehog pathway was evaluated in vivo using a mouse xenograft model prepared using pancreatic cancer cell line Paca-44. Mice were treated by experimental Stony Brook Taxane SB-T-1216. The transcript profile of 34 Hedgehog pathway genes in patients and xenografts was assessed using quantitative PCR. The Hedgehog pathway was strongly overexpressed in pancreatic tumors and upregulation of SHH, IHH, HHAT and PTCH1 was associated with a trend toward decreased patient survival. No association of Hedgehog pathway expression with KRAS mutation status was found in tumors. Sonic hedgehog ligand was overexpressed, but all other downstream genes were downregulated by SB-T-1216 treatment in vivo. Suppression of HH pathway expression in vivo by taxane-based chemotherapy suggests a new mechanism of action for treatment of this aggressive tumor.

[Clinical and Functional Importance of Selected CASP8 and CASP9 Polymorphisms in Breast Carcinoma]. / Klinický a funkcní význam vybraných polymorfizmu CASP8 a CASP9 u karcinomu prsu.

BACKGROUND: Caspase-8 and caspase-9 (encoded by CASP8 and CASP9) are executive caspases of programmed cell death (apoptosis). Dysregulation of apoptosis plays an important role in cancer development, progression, and resistance to anticancer therapy. The goal of this work was to evaluate potential associations between polymorphisms in CASP8 and CASP9, previously linked to breast cancer risk, and the transcript levels of these genes (including their alternative anti-apoptotic variants) in tumor tissues and the clinical characteristics of the patients. MATERIAL AND METHODS: Sanger sequencing, high resolution melting (HRM) analysis, and allelic discrimination were used to identify polymorphisms in DNA samples isolated from tumor tissues and peripheral blood lymphocytes of 60 breast carcinoma patients. Total transcript levels of CASP8 and CASP9, and levels of alternative splicing variants CASP8L and CASP9B, were quantified by real-time PCR in tumor tissues. Clinically interesting associations were validated in DNA from lymphocytes of 615 breast carcinoma patients. RESULTS: A haplotype in CASP9 composed of three polymorphisms rs4645978-rs2020903-rs4646034 was significantly associated with CASP9 expression in tumors, with the expression of the progesterone receptor and ERBB2, and with the TNBC subtype of breast carcinoma in the validation study. The associations between the rs3834129 polymorphism in CASP8 and stage of disease, rs6435074 with grade, expression of estrogen receptor and ERBB2, and rs6723097 with ERBB2 expression have not yet been validated. However, rs6723097 was associated with disease-free survival in patients treated with hormonal therapy. CONCLUSION: This study reveals a previously unknown and presumably functional (in silico) association between a haplotype in CASP9 and molecular and clinical phenotypes of breast carcinoma. The potential clinical utility of this association for prognostication of breast carcinoma should be evaluated by independent studies.Key words: breast carcinoma - caspases - polymorphisms - functional - clinical - importanceThis work was supported by grant of the CU Grant Agency No. 1444313, and grant of the Internal Grant Agency of the Czech Ministry of Health No. 15-25618A.The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 3. 3. 2016Accepted: 26. 10. 2016.