Regulation of cellular sphingosine-1-phosphate by sphingosine kinase 1 and sphingosine-1-phopshate lyase determines chemotherapy resistance in gastroesophageal cancer.

BACKGROUND: Resistance to chemotherapy is common in gastroesophageal cancer. Mechanisms of resistance are incompletely characterised and there are no predictive biomarkers in clinical practice for cytotoxic drugs. We used new cell line models to characterise novel chemotherapy resistance mechanisms and validated them in tumour specimens to identify new targets and biomarkers for gastroesophageal cancer. METHODS: Cell lines were selected for resistance to oxaliplatin, cisplatin and docetaxel and gene expression examined using Affymetrix Exon 1.0 ST arrays. Leads were validated by qRT-PCR and HPLC of tumour metabolites. Protein expression and pharmacological inhibition of lead target SPHK1 was evaluated in independent cell lines, and by immunohistochemistry in gastroesophageal cancer patients. RESULTS: Genes with differential expression in drug resistant cell lines compared to the parental cell line they were derived from, were identified for each drug resistant cell line. Biological pathway analysis of these gene lists, identified over-represented pathways, and only 3 pathways - lysosome, sphingolipid metabolism and p53 signalling- were identified as over-represented in these lists for all three cytotoxic drugs investigated. The majority of genes differentially expressed in chemoresistant cell lines from these pathways, were involved in metabolism of glycosphingolipids and sphingolipids in lysosomal compartments suggesting that sphingolipids might be important mediators of cytotoxic drug resistance in gastroeosphageal cancers . On further investigation, we found that drug resistance (IC50) was correlated with increased sphingosine kinase 1(SPHK1) mRNA and also with decreased sphingosine-1-phosphate lysase 1(SGPL1) mRNA. SPHK1 and SGPL1 gene expression were inversely correlated. SPHK1:SGPL1 ratio correlated with increased cellular sphingosine-1-phosphate (S1P), and S1P correlated with drug resistance (IC50). High SPHK1 protein correlated with resistance to cisplatin (IC50) in an independent gastric cancer cell line panel and with survival of patients treated with chemotherapy prior to surgery but not in patients treated with surgery alone. Safingol a SPHK1 inhibitor, was cytotoxic as a single agent and acted synergistically with cisplatin in gastric cancer cell lines. CONCLUSION: Agents that inhibit SPHK1 or S1P could overcome cytotoxic drug resistance in gastroesophageal cancer. There are several agents in early phase human trials including Safingol that could be combined with chemotherapy or used in patients progressing after chemotherapy.

Achieving Benchmarks for National Quality Indicators Reduces Recurrence and Progression in Non-muscle-invasive Bladder Cancer.

BACKGROUND: Noncompliance with evidence-based interventions and guidelines contributes to significant and variable recurrence and progression in patients with non-muscle-invasive bladder cancer (NMIBC). The implementation of a quality performance indicator (QPI) programme in Scotland's National Health Service (NHS) aimed to improve cancer outcomes and reduce nationwide variance. OBJECTIVE: To evaluate the effect of hospitals achieving benchmarks for two specific QPIs on time to recurrence and progression in NMIBC. DESIGN, SETTING, AND PARTICIPANTS: QPIs for bladder cancer (BC) were enforced nationally in April 2014. NHS health boards collected prospective data on all new BC patients. Prospectively recorded surveillance data were pooled from 12 collaborating centres. INTERVENTION: QPIs of interest were (1) hospitals achieving detrusor muscle (DM) sampling target at initial transurethral resection of bladder tumour (TURBT) and (2) use of single instillation of mitomycin C after TURBT (SI-MMC). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary and secondary endpoints were time to recurrence and progression, respectively. Kaplan-Meier and Cox multivariable regression analyses were performed. KEY FINDINGS AND LIMITATIONS: Between April 1, 2014 and March 31, 2017, we diagnosed 3899 patients with new BC, of which 2688 were NMIBC . With a median follow up of 60.3 mo, hospitals achieving the DM sampling target had a 5.4% lower recurrence rate at 5 yr than hospitals not achieving this target (442/1136 [38.9%] vs 677/1528 [44.3%], 95% confidence interval [CI] = 1.6-9.2, p = 0.005). SI-MMC was associated with a 20.4% lower recurrence rate (634/1791 [35.4%] vs 469/840 [55.8%], 95% CI = 16.4-24.5, p < 0.001). On Cox multivariable regression, meeting the DM target and SI-MMC were associated with significant improvement in recurrence (hazard ratio [HR] 0.81, 95% CI = 0.73-0.91, p = 0.0002 and HR 0.66, 95% CI = 0.59-0.74, p < 0.004, respectively) as well as progression-free survival (HR 0.62, 95% CI = 0.45-0.84, p = 0.002 and HR 0.65, 95% CI = 0.49-0.87, p = 0.004, respectively). We did not have a national multicentre pre-QPI control. CONCLUSIONS: Within a national QPI programme, meeting targets for sampling DM and SI-MMC in the real world were independently associated with delays to recurrence and progression in NMIBC patients. PATIENT SUMMARY: Following the first 3 yr of implementing a novel quality performance indicator programme in Scotland, we evaluated compliance and outcomes in non-muscle-invasive bladder cancer. In 2688 patients followed up for 5 yr, we found that achieving targets for sampling detrusor muscle and the single instillation of mitomycin C during and after transurethral resection of bladder tumour, respectively, were associated with delays in cancer recurrence and progression.

Do patients' faces influence General Practitioners' cancer suspicions? A test of automatic processing of sociodemographic information.

BACKGROUND: Delayed cancer diagnosis leads to poorer patient outcomes. During short consultations, General Practitioners (GPs) make quick decisions about likelihood of cancer. Patients' facial cues are processed rapidly and may influence diagnosis. AIM: To investigate whether patients' facial characteristics influence immediate perception of cancer risk by GPs. DESIGN AND SETTING: Web-based binary forced choice experiment with GPs from Northeast Scotland. METHOD: GPs were presented with a series of pairs of face prototypes and asked to quickly select the patient more likely to have cancer. Faces were modified with respect to age, gender, and ethnicity. Choices were analysed using Chi-squared goodness-of-fit statistics with Bonferroni corrections. RESULTS: Eighty-two GPs participated. GPs were significantly more likely to suspect cancer in older patients. Gender influenced GP cancer suspicion, but this was modified by age: the male face was chosen as more likely to have cancer than the female face for young (72% of GPs;95% CI 61.0-87.0) and middle-aged faces (65.9%; 95% CI 54.7-75.5); but 63.4% (95% CI 52.2-73.3) decided the older female was more likely to have cancer than the older male (p = 0.015). GPs were significantly more likely to suspect cancer in the young Caucasian male (65.9% (95% CI 54.7, 75.5)) compared to the young Asian male (p = 0.004). CONCLUSION: GPs' first impressions about cancer risk are influenced by patient age, gender, and ethnicity. Tackling GP cognitive biases could be a promising way of reducing cancer diagnostic delays, particularly for younger patients.

The medical experience of a patient with a rare disease and her family.

This letter considers the main challenges that people with rare diseases and their families face: delay in diagnosis, lack of appropriate support and information, and impaired access to treatment. The differences in medical experience between a patient with a rare disease and one with a common one are made through the use of a real-life example: the diagnosis of leiomyosarcoma received by my mother. I highlight how patients with rare disease are often misdiagnoses and how their symptoms are often overlooked. I also highlight the isolation patients with rare diseases and their families experience due to the lack of knowledge about their condition, the struggle to access treatment and the small amount of information and evidence based medicine for managing rare conditions.This article was the winning entry in the Findacure essay contest 'The Student Voice'. More information about Findacure can be found at http://www.findacure.org.uk .