Fast and simple detection methods for the 4-base pair deletion of canine MDR1/ABCB1 gene by PCR and isothermal amplification

Dogs with a 4-bp deletion in the MDR1 (or ABCB1) gene show intolerance to certain drugs routinely used in veterinary medicine, such as ivermectin, vincristine, and doxorubicin. The mutation leads to a dysfunctional P-glycoprotein drug transporter, which results in drug accumulation in the brain and severe neurotoxicity. A rapid and accurate in-house test to determine the genotype of patients in cases of acute neurotoxic signs or in tumor patients is desirable. We describe a cost-effective detection method with simple technical equipment for veterinary practice. Two allele-specific methods are presented, which allow discrimination of all genotypes, require little hands-on time, and show the results within similar to 1 h after DNA sampling. DNA from buccal swabs of 115 dogs with known genotype (no mutation, n = 54;heterozygous for the mutation, n = 37;homozygous for the mutation, n = 24) was extracted either by using a column-based extraction kit or by heating swabs in a simple NaOH-Tris buffer. Amplification was performed either by allele-specific fast polymerase chain reaction or by allele-specific loop-mediated isothermal amplification (LAMP). Analysis was done either on agarose gels, by simple endpoint visualization using ultraviolet light, or by measuring the increase of fluorescence and time to threshold crossing. Commercial master mixes reduced the preparation time and minimized sources of error in both methods. Both methods allowed the discrimination of all 3 genotypes, and the results of the new methods matched the results of the previous genotyping. The presented methods could be used for fast individual MDR1/ABCB1 genotyping with less equipment than existing methods

SOX2 gene amplification and protein overexpression are associated with better outcome in squamous cell lung cancer

The transcription factor SOX2 (3q26.3-q27) is a key regulator of foregut development and an embryonic stem cell factor cooperating during induction of pluripotency in terminally differentiated somatic cells. Recently, we found SOX2 to be amplified in a subset of squamous cell lung and esophageal cancers. The aim of this study was to explore the prognostic role of SOX2 in a large series of squamous cell carcinomas and adenocarcinomas of the lung. A total of 891 samples from two independent population-based cohorts were assessed by fluorescence in situ hybridization and immunohistochemistry. Furthermore, we assessed for associations between SOX2 amplification/upregulation and clinicopathological features. Similar results were found in the two cohorts. Within squamous cell carcinoma cases, 8% high-level as well as 68 and 65% low-level SOX2 amplifications occurred in the two cohorts, respectively. In adenocarcinomas, no high-level amplification was found and low-level amplification occurred in 6% of the two cohorts. Within squamous cell carcinomas of one cohort, SOX2 amplification was associated with lower tumor grade, while higher levels of SOX2 expression were related to younger age, smaller tumor size, and lower probability of angiolymphatic invasion and metastasis. High SOX2 expression levels proved to be a marker for prolonged overall survival among patients with squamous cell carcinomas. In conclusion, SOX2 amplification and upregulation are frequent events in squamous cell carcinomas of the lung and are associated with indicators of favorable prognosis