Confocal foveated endomicroscope for the detection of esophageal carcinoma

Cardiac tropoini T (TNNT2) plays a potential oncogenic role in colorectal carcinogenesis

PURPOSE

Colorectal cancer (CRC) is the third most common cancer in the world. The purpose of this study was to investigate the role of TNNT2 in the proliferation, migration and invasion of CRC cells and its expression in CRC tissues to better understand the regulatory role of TNNT2 in CRC.

METHODS

Western blotting (WB) and qPCR were used to detect the expression of TNNT2 in colorectal cancer tissues and paracancerous tissues. CCK-8, colony formation, Transwell and other experiments were used to clarify the role of TNNT2 in the proliferation, migration and invasion of colorectal cancer cells. Changes in TNNT2, EGFR and HER2 mRNA transcription levels were detected by SYBR Real-Time PCR assay, and the effects of TNNT2 overexpression or knockdown on the expression of EGFR, HER2 and EMT-related proteins in CRC cells were determined by WB. TNNT2 and EGFR intreaction was carried out in HCT116 cells by coimmunoprecipitation experiments.

RESULTS

The protein and mRNA expression level of TNNT2 in CRC tissues were higher than those in paracancerous tissues. The CCK-8 results suggested that overexpression of TNNT2 significantly promoted the proliferation of HCT116 and RKO cells, and TNNT2 konckdown gets the opposite result; and the colony formation results were the same as tthose of CCK-8 assay. Transwell invasion and migration experiments showed that overexpression of TNNT2 promoted the migration and invasion of HCT116 and PKO cells, and TNNT2 konckdown suppressed the migration and invasion of the these cells. The SYBR Green I real-time PCR method revealed that them RNA levels of TNNT2, EGFR and HER2 in the TNNT2 overexpression group were higher than those in RKO cells. WB showed that overexpressing TNNT2 increased the expression of EGFR and HER2 in HCT16 and RKO cells,decreased the expression of EMT marker E-cadherin, and increased the expression of Vimentin and N-cadherin. Konckdown of TNNT2 decreased the expression of EGFR and HER2, increased the expression of E-cadherin, and decreased the expression of Vimentin and N-cadherin in HCT16 and RKO cells. The immunocoprecipitation experiment showed that there was an interaction between EGFR and TNNT2.

CONCLUSION

TNNT2 can promote the proliferation, invasion and metastasis of colorectal cancer cells. There is an interaction between TNNT2 and EGFR protein. TNNT2 can upregulate EGFR and HER2-related proteins in colorectal cancer cells and promote the occurrence of EMT. Therefore, TNNT2 can promote the invasion and metastasis of CRC cells through the EGFR/HER2/EMT signal axis, suggesting that TNNT2 is a potential target of CRC treatment.

Endoscopic optical coherence tomography with a focus-adjustable probe

We present a focus-adjustable endoscopic probe for optical coherence tomography (OCT), which is able to acquire images with different focal planes and overcome depth-of-focus limitations by image fusing. The use of a two-way shape-memory-alloy spring enables the probe to adjust working distance over 1.5 mm, providing a large scanning range with high resolution and no sensitivity loss. Equipped with a homemade hollow-core ultrasonic motor, the probe is capable of performing an unobstructed 360 deg field-of-view distal scanning. Both the axial resolution and the best lateral resolution are ∼4  μm, with a sensitivity of 100.3 dB. Spectral-domain OCT imaging of phantom and biological tissues with the probe is also demonstrated.

Development of a multimodal foveated endomicroscope for the detection of oral cancer

A multimodal endomicroscope was developed for cancer detection that combines hyperspectral and confocal imaging through a single foveated objective and a vibrating optical fiber bundle. Standard clinical examination has a limited ability to identify early stage oral cancer. Optical detection methods are typically restricted by either achievable resolution or a small field-of-view. By combining high resolution and widefield spectral imaging into a single probe, a device was developed that provides spectral and spatial information over a 5 mm field to locate suspicious lesions that can then be inspected in high resolution mode. The device was evaluated on ex vivo biopsies of human oral tumors.

Possible tumor suppressive role of the miR-144/451 cluster in esophageal carcinoma as determined by principal component regression analysis

MicroRNA (miRNA) clusters are expressed universally across different types of organisms, and an accumulating number of studies have demonstrated that miRNA clusters function more efficiently compared with single miRNAs during the development of certain cancer types. miRNA clusters may have increased stability and reliability over individual miRNAs as diagnostic or therapeutic biomarkers. In the present study, the expression levels of mature miRNAs within the miR-144/451 cluster were examined using stem‑loop reverse transcription‑quantitative polymerase chain reaction in 102 patients pathologically diagnosed with esophageal carcinoma. Bioinformatics tools were used to identify a possible miRNA‑mediated network of the miR‑144/451 cluster. The expression levels of hsa‑miR‑451a, hsa‑miR‑144‑3p and hsa‑miR‑144‑5p in tumor tissues were significantly lower compared with those in adjacent non‑tumor tissues (P<0.05). Pearson correlation analysis demonstrated that the expression levels of individual miR‑144/451 cluster members were correlated with each other, except for the pair of hsa‑miR‑144‑3p and hsa‑miR‑4732‑3p. In particular, hsa‑miR‑144‑5p expression was highly associated with hsa-miR-4732‑5p and hsa-miR-451a expression levels, with correlation coefficients of 0.729 and 0.608, respectively. Furthermore, the low expression levels of hsa‑miR‑144‑3p [odds ratio (OR), 0.85; P<0.05] and hsa-miR-144-5p (OR, 0.84; P<0.05) were determined to be risk factors for esophageal carcinoma development. Kyoto Encyclopedia of Genes and Genomes pathway analysis demonstrated that miRNAs forming the miR‑144/451 cluster may cooperate to regulate the cell cycle. Therefore, the miR‑144/451 cluster may serve an important role in the progression of esophageal carcinoma and may be considered as a biomarker for the detection of esophageal carcinoma at an early stage.

Design and fabrication of a miniature objective consisting of high refractive index zinc sulfide lenses for laser surgery

A miniature laser ablation probe relying on an optical fiber to deliver light requires a high coupling efficiency objective with sufficient magnification in order to provide adequate power and field for surgery. A diffraction-limited optical design is presented that utilizes high refractive index zinc sulfide to meet specifications while reducing the miniature objective down to two lenses. The design has a hypercentric conjugate plane on the fiber side and is telecentric on the tissue end. Two versions of the objective were built on a diamond lathe-a traditional cylindrical design and a custom-tapered mount. Both received an antireflective coating. The objectives performed as designed in terms of observable resolution and field of view as measured by imaging a 1951 USAF resolution target. The slanted edge technique was used to find Strehl ratios of 0.75 and 0.78, respectively, indicating nearly diffraction-limited performance. Finally, preliminary ablation experiments indicated threshold fluence of gold film was comparable to similar reported probes.