Sensitive tear screening of diabetic retinopathy with dual biomarkers enabled using a rapid electrokinetic patterning platform.

Bead-based immunosensors have intrigued the scientific community over the past decades due to their rapid and multiplexed capabilities in the detection of various biological targets. Nevertheless, their use in the detection of low-abundance analytes remains a continuing challenge because of their limited number of active enrichment approaches. To this end, our research presents a delicate microbead enrichment technique using an optoelectrokinetic platform, followed by the detection of dual biomarkers for the sensitive screening of an eye disease termed diabetic retinopathy (DR). In this study, microbeads turned fluorescent as their surfaces formed sandwiched immunocomplexes in the presence of target antigens. The tiny fluorescent dots were then concentrated using the optoelectrokinetic platform for the enhancement of their signals. The signal rapidly escalated in 10 s, and the optimal limit of detection was nearly 100 pg mL-1. For practical DR screening, two biomarkers, lipocalin 1 (LCN1) and vascular endothelial growth factor (VEGF), were used. Approximately 20 µL of analytes were collected from the tear samples of the tested patients. The concentrations of both biomarkers showed escalating trends with the severity of DR. Two concentration thresholds of LCN1 and VEGF that indicate proliferative DR were determined out of 24 clinical samples based on the receiver operating characteristic curves. For verification, a single-blind test was conducted with additional clinical tear samples from five random subjects. The final outcome of this evaluation showed an accuracy of >80%. This non-invasive screening provides a potential means for the early diagnosis of DR and may increase the screening rate among the high-risk diabetic population in the future.

Neoadjuvant therapy of bevacizumab in combination with oxaliplatin and capecitabine (XELOX) for patients with metastatic colorectal cancer with unresectable liver metastases: a phase II, open-label, single-arm, noncomparative trial.

AIM: This phase II, open-label study evaluated the efficacy and safety of neoadjuvant therapy with bevacizumab plus XELOX (capecitabine and oxaliplatin) for untreated metastatic colorectal cancer with unresectable liver metastases and assessed conversion of unresectable to resectable metastases after neoadjuvant treatment. METHODS: Patients received bevacizumab 5 mg/kg and oxaliplatin 85 mg/m2 on day 1, and capecitabine 1000 mg/m2 twice daily on days 1-5 followed by 2 days of rest in a 14-day cycle for 12 cycles; bevacizumab was excluded in cycles 6 and 7. Patients were later divided into resected and unresected groups, depending upon whether they underwent curative resection after chemotherapy. Efficacy and safety were evaluated. RESULTS: Of 45 patients enrolled, 17.8% completed the study. The resection rate of liver metastases after neoadjuvant therapy was 42.2%. The median time to disease progression was 10.1 and 8.7 months in the resected and unresected groups, respectively (P = 0.1341). Response rate was significantly higher in the resected (47.4%) versus the unresected group (34.6%; P = 0.0010), and seven patients achieved complete response (resected group). Overall, 94.3% of adverse events were of mild or moderate severity, and grade ≥3 adverse events occurred in 4.3% and 7.3% of patients in the resected and unresected groups, respectively. The most common adverse events in both groups were palmar-plantar erythrodysesthesia syndrome, decreased appetite, thrombocytopenia, peripheral neuropathy, fatigue, diarrhea, vomiting, proteinuria and nausea. CONCLUSION: Neoadjuvant therapy with bevacizumab plus XELOX was well tolerated and effective in previously untreated metastatic colorectal cancer patients with initially unresectable liver metastases.

S100P, a calcium-binding protein, is preferentially associated with the growth of polypoid tumors in colorectal cancer.

Colorectal cancer (CRC) is a genetically heterogeneous disease with distinct morphological patterns. It has been shown that polypoid and ulcerative CRC displays different genetic alterations. In the present study, we aimed to investigate genes with differential expression patterns between ulcerative and polypoid CRC. cDNA microarray analysis was performed to compare the gene expression profiles in samples of ulcerative and polypoid CRC with paired normal mucosa samples. Potential candidate genes were further validated using reverse transcription-quantitative polymerase chain reaction (RT-qPCR), western blot analysis and immunohistochemistry. The epigenetic regulation of gene expression was investigated using methylation-specific PCR (MSP). cDNA microarray analysis identified 11 upregulated and 14 downregulated genes which were differentially expressed in samples from both tumor types compared to the matched normal mucosa samples. Among these, S100P was the only upregulated gene preferentially associated with polypoid CRC (P=0.032). The samples of polypoid CRC displayed significantly higher S100P protein and mRNA expression levels than the samples of ulcerative CRC (P<0.05, respectively). Using semi-quantitative immunohistochemical analyses, S100P overexpression was found to be preferentially associated with polypoid CRC (24/30 vs. 14/40, P<0.001). The relative methylation level determined by MSP did not differ significantly between the samples of polypoid and ulcerative CRC (43.36 vs. 49.10%, P=0.168), indicating that promoter hypomethylation was not directly related to the upregulation of S100P mRNA. Our results demonstrate that the upregulation of S100P mRNA and protein expression is a predominant characteristic in polypoid CRC, whereas ulcerative CRC presents with a wide range of expression levels, indicating that S100P overexpression is not a key determinant in conferring invasion properties. The clinicopathological significance of S100P in CRC requires further investigation in well-controlled studies.

Activation of human telomerase reverse transcriptase expression by some new symmetrical bis-substituted derivatives of the anthraquinone.

As a part of our program aimed at exploring the biological activity of symmetrical substitution of side chains into the anthracene-9,10-dione chromophore, we have synthesized a series of 1,5-bisthioanthraquinones 2 and 1,5-bisacyloxyanthraquinones 3 that are related to the antitumor agent mitoxantrone. Since the telomerase enzyme is a novel target for potential anticancer therapy and stem cell expansion, we explore the biological effects of these compounds by evaluating their effects on telomerase activity and telomerase expression. Telomerase is required for telomere maintenance and is active in most human cancers and in germinal cells but not in most of the normal human somatic tissues. We found that most of the 1,5-disubstituted anthraquinones did not exhibit inhibitory activity at the concentration ranging from 20 to 30 microM. To facilitate the analysis of the expression of telomerase, we used cancer and normal cell lines that carry secreted alkaline phosphatase (SEAP) gene under the control of human telomerase reverse transcriptase (hTERT). The effects of these compounds on the expression of telomerease were analyzed using the cell-based reporter systems. While most of these compounds did not appear to selectively repress the expression of hTERT in cancer cells, compounds 3a, 3d, and 3i activated hTERT expression in normal cells. The effects of these three compounds on hTERT expression appear to be specific because they did not increase the expression of a CMV promoter-driven SEAP. Thus, in addition to anticancer functions, our finding raises the possibility that these compounds might also have a role in cell immortalization. The application of these anthraquinone derivatives in stem cell research and tissue engineering is also discussed.