Association of Common and Rare Genetic Variation in the 3-Hydroxy-3-Methylglutaryl Coenzyme A Reductase Gene and Cataract Risk.

Background Results from animal models and observational studies have raised concerns regarding the potential cataractogenic effects of statin treatment. We investigated whether common and rare genetic variants in HMGCR are associated with cataract risk, to gauge the likely long-term effects of statin treatment on lenticular opacities. Methods and Results We used genotyping data and exome sequencing data of unrelated European individuals in the UK Biobank to test the association between genetically proxied inhibition of HMGCR and cataract risk. First, we constructed an HMGCR genetic score consisting of 5 common variants weighted by their association with low-density lipoprotein cholesterol. Second, we analyzed exome sequencing data to identify carriers of predicted loss-of-function mutations in HMGCR. Common and rare variants in aggregate were then tested for association with cataract and cataract surgery. In an analysis of >402 000 individuals, a 38.7 mg/dL (1 mmol/L) reduction in low-density lipoprotein C by the HMGCR genetic score was associated with higher risk for cataract (odds ratio, 1.14 [95% CI, 1.00-1.39], P=0.045) and cataract surgery (odds ratio, 1.25 [95% CI, 1.06-1.48], P=0.009). Among 169 172 individuals with HMGCR sequencing data, we identified 32 participants (0.02%), who carried a rare HMGCR predicted loss-of-function variant. Compared with noncarriers, heterozygous carriers of HMGCR predicted loss-of-function had a higher risk of developing cataract (odds ratio, 4.54 [95% CI, 1.96-10.53], P=0.001) and cataract surgery (odds ratio, 5.27 [95% CI, 2.27-12.25], P=5.37×10-4). In exploratory analyses, we found no significant association between genetically proxied inhibition of PCSK9, NPC1L1, or circulating low-density lipoprotein cholesterol levels (P>0.05 for all) and cataract risk. Conclusions We found that genetically proxied inhibition of the HMGCR gene mimicking long-term statin treatment associated with higher risk of cataract. Clinical trials with longer follow-up are needed to confirm these findings.

Comparative efficacy and safety of preserved versus preservative-free beta-blockers in patients with glaucoma or ocular hypertension: a systematic review.

Preservative-free topical medications have been introduced for glaucoma care to reduce ocular adverse events associated with preservatives. This is a systematic review and meta-analysis of randomized clinical trials (RCTs) comparing the efficacy and safety of beta-blockers, or combination using beta-blockers, with and without preservatives. PubMed, EMBASE and Web of Science were examined. Risk of bias was assessed using the Cochrane Handbook for Systematic Reviews. The primary outcome was change in intraocular pressure (IOP) from baseline to final follow-up. Secondary outcomes included ocular and systemic side effects, and other clinical and quality of life outcomes. Of 242 records identified, seven RCTs (1125 patients) were included. The follow-up period ranged from one to 12 months. Timolol was used in five studies, and two studies used a combination (timolol with bimatoprost or dorzolamide). The difference in mean change (MD) in IOP between the preservative-free and the preserved drugs was statistically significant but not clinically relevant: (MD 0.29 mmHg, 95% confidence interval 0.07-0.51 mmHg, p = 0.010; moderate-certainty evidence). Regarding adverse events: Level of evidence for all ocular surface outcome was low or very low and reported in few studies. No significant difference was observed on ocular surface symptoms. Tear break-up time (TBUT) was better with preservative-free drops (p < 0.001). Schirmer's test was better in the preservative-free group (p < 0.001). Level of evidence for all ocular surface outcomes was low or very low. There was no difference in other secondary outcomes. We found no clinically relevant difference in mean change in IOP between the preserved and the preservative-free treatments. Data on adverse events used different methods and were incompletely reported. Although some measures of ocular surface health favoured preservative-free medications, more evidence is needed. The increasing use of preservative-free drops may be associated with better ocular surface and tolerability, but strong evidence from RCTs would be welcome.

Leser­Trélat syndrome in malignant mesothelioma and pulmonary adenocarcinoma: is the EGFR pathway part of the syndrome?

The syndrome of Leser­Trélat (LT) is characterized by the sudden appearance of multiple seborrhoeic keratoses (SKs) in association with internal occult malignancy. Usually, the syndrome has been associated with adenocarcinoma, most frequently of the gastrointestinal tract and breast. The pathogenesis is unclear but might be explained by circulating tumor-associated growth factors. We present two thoracic malignancies associated with LT: adenocarcinoma of the lung (ACL) and pleural malignant mesothelioma (MM). Both malignant tumors expressed high levels of epidermal growth factor receptors (EGFR) detected by immunohistochemistry (IHC), with membranous staining on the majority of malignant cells corresponding to maximum IHC scores of 290 and 300, respectively, for the MM and the ACL. SKs revealed a universal membranous staining throughout the entire epithelium with no difference in EGFR expression between the two cases and two controls with no malignant history. By fluorescence in situ hybridization, no amplification of the EGFR gene in malignant tumors as well as in SK lesions was observed. Further investigations are needed to see whether tumor-associated EGFR ligands/EGFR autocrine loops in malignant cells expressing high levels of EGFR protein on the surface might play a role for the development of SKs, as well as for the growth of malignant tumors in LT.

cMyc/miR-125b-5p signalling determines sensitivity to bortezomib in preclinical model of cutaneous T-cell lymphomas.

Successful/effective cancer therapy in low grade lymphoma is often hampered by cell resistance to anti-neoplastic agents. The crucial mechanisms responsible for this phenomenon are poorly understood. Overcoming resistance of tumor cells to anticancer agents, such as proteasome inhibitors, could improve their clinical efficacy. Using cutaneous T-cell lymphoma (CTCL) as a model of the chemotherapy-resistant peripheral lymphoid malignancy, we demonstrated that resistance to proteasome inhibition involved a signaling between the oncogene cMyc and miR-125b-5p. Bortezomib repressed cMyc and simultaneously induced miR-125b-5p that exerted a cytoprotective effect through the downmodulation of MAD4. Overexpression of cMyc repressed miR-125b-5p transcription and sensitized lymphoma cells to bortezomib. The central role of miR-125b-5p was further confirmed in a mouse model of T-cell lymphoma, where xenotransplantation of human CTCL cells overexpressing miR-125b-5p resulted in enhanced tumor growth and a shorter median survival. Our findings describe a novel mechanism through which miR-125b-5p not only regulates tumor growth in vivo, but also increases cellular resistance to proteasome inhibitors via modulation of MAD4.

miR-122 regulates p53/Akt signalling and the chemotherapy-induced apoptosis in cutaneous T-cell lymphoma.

Advanced cutaneous T-cell lymphoma (CTCL) is resistant to chemotherapy and presents a major area of medical need. In view of the known role of microRNAs (miRNAs) in the regulation of cellular signalling, we aimed to identify the functionally important miRNA species, which regulate apoptosis in CTCL. Using a recently established model in which apoptosis of CTCL cell lines is induced by Notch-1 inhibition by γ-secretase inhibitors (GSIs), we found that miR-122 was significantly increased in the apoptotic cells. miR-122 up-regulation was not specific for GSI-1 but was also seen during apoptosis induced by chemotherapies including doxorubicin and proteasome blockers (bortezomib, MG132). miR-122 was not expressed in quiescent T-cells, but was detectable in CTCL: in lesional skin in mycosis fungoides and in Sézary cells purified from peripheral blood. In situ hybridization results showed that miR-122 was expressed in the malignant T-cell infiltrate and increased in the advanced stage mycosis fungoides. Surprisingly, miR-122 overexpression decreased the sensitivity to the chemotherapy-induced apoptosis via a signaling circuit involving the activation of Akt and inhibition of p53. We have also shown that induction of miR-122 occurred via p53 and that p53 post-transcriptionally up-regulated miR-122. miR-122 is thus an amplifier of the antiapoptotic Akt/p53 circuit and it is conceivable that a pharmacological intervention in this pathway may provide basis for novel therapies for CTCL.