A DUAL-MODALITY OPTICAL BIOPSY APPROACH FOR IN VIVO DETECTION OF PROSTATE CANCER IN RAT MODEL

Ultrasound-guided biopsy procedure for prostate cancer diagnosis,which is the current gold standard,involves quasi-random sampling of prostate tissue without any functional guidance.In this study,we discuss the possibility to augment the detection of prostate cancer using a dual-modality optical approach,which can be coupled with the current needle biopsy setup.Two techniques are light reflectance spectroscopy(LRS)that uses a broadband light source and a CCD array spectrometer,and auto-fluorescence lifetime measurement(AFLM)that uses a custom-designed,time-correlated single photon counting(TCSPC)system.Both LRS and AFLM were employed sequentially in this study to measure cancer tissue along with control tissue on a rat prostate tumor model.At an excitation wavelength of 447 nm,we investigated auto-fluorescence decay curves at the emission wavelengths of 532,562,632 and 684 nm for in vivo and ex vivo AFLM.These results show that auto-fluorescence lifetimes at all measured emission wavelengths differ between control and cancerous tissues with 100% specificity and sensitivity.Moreover,absolute values of hemoglobin derivatives and scattering coe±cient were quantified using in vivo LRS.This part of study also demonstrates that light scattering and absorption are significantly different between the control and cancerous tissue.Overall,the study demonstrates that both LRS and AFLM may provide several intrinsic biomarkers for in vivo detection of prostate cancer.

Acquired Pigmentation of Porcine Lymph Nodes: Dietary Polyphenolic Compounds as Biological Markers?

The investigation aimed at exploring whether 1) high contents of natural polyphenols from the diet can induce pigment accumulation in lymph nodes (LNs);2) if so, whether polyphenolic compounds and derivates can be used as biological markers;3) and whether a lymph node from a specific anatomical region can be univocally identified, so as to be con sidered as a sentinel for the identification of the dietary origin of pigments. A paired match approach was used to switch 20 pigs (range of initial body weight, BW: 113 - 121 kg) to two experimental diets, for four weeks: ten pigs (pair housed) were fed with an experimental acorn based diet (acorns: 50% in the diet, as fed;total polyphenols, 78.1 g TP/Kg DM in the diet;tannic acid equivalent, 25.8 g TAE/kg DM);the remainder ten, received a pelleted complete diet for finishers (0% acorns in the diet). Daily feed intake in the last two weeks of the experimental feeding was recorded per pair of pigs in both groups of animals, showing an average intake of 610 mg TAE/kg BW/d. At an average final BW of between 127 to 137 kg, all pigs were slaughtered and LNs from different anatomical regions of the carcass were removed and analysed. At gross inspection, LNs from both groups displayed different grades of intensity and diffusion of pigmentation: a partial and incidental pigmentation was randomly detected in renal or sub-iliac LNs in the control group;a constant and uniform pigmentation of LNs was observed in acorns fed pigs: a dark brown staining diffused to the whole LN associated with a brownish colour of the muscles was found systematically. At light microscope intracytoplasmic granules were found in macrophages and dendritic cells from both groups, but, at confocal laser analysis, an intense auto-fluorescence was observed in medial-iliac LNs from the carcasses of acorn-fed pigs (green emission). However, intracellular sources of blue and green fluorescence at different wavelengths, likely due to tryptophan, indoleamine and derivates were also found in medial-iliac and inguinal LNs from the control group. A dietary origin was attributed to the different discoloration of LNs between the carcasses of the two groups: such acquired pigmentation is relevant in the left sub-iliac LN, but the confocal laser microscopic test to elicit auto-fluorescence of polyphenolic compounds (biological markers) displayed a 76.9% specificity, despite a 100% of sensitivity for the univocal identification of the carcass from acorn-fed pigs. Cranial sternal LNs resulted to suit the sentinel role in the distinction of carcass from acorns fed pigs at confocal laser microscopic analysis.

Usefulness of Immuno-Magnetic Beads Conjugated with Anti-EpCAM Antibody for Detecting Endometrial Cancer Cells

A simple and non-invasive method for detecting endometrial cancer in women with abnormal uterine bleeding is required. For this purpose, we prepared immuno-magnetic beads conjugated with anti-human EpCAM rat monoclonal antibody (mAb) for isolating exfoliated endometrial cells including endometrial cancer cells in vaginal discharge. The affinities of the anti-human EpCAM rat mAbs were analyzed by flow cytometry and immunocytochemistry and then magnetic beads were conjugated with the mAbs. The rate of retrieval of endometrial cells using the immuno-magnetic beads was calculated. Endometrial cells were isolated using the immuno-magnetic beads from the vaginal discharges of 22 patients with endometrial cancer and 16 non-malignant controls. The isolated cells were stained using endometrial cancer specific-mAbs and analyzed by flow cytometry and imaging cytometry. The immuno-magnetic beads conjugated with high-affinity mAb (clone 1456) appeared to have very low auto-fluorescence. Sufficient enrichment of Ep-CAMpositive cells using immuno-magnetic beads was observed in both simulation and clinical samples. The overall sensitivities of flow cytometry and imaging cytometry to detect endometrial cancer cells were 72.7% and 45.5%, respectively. Meanwhile, the overall specificities of flow cytometry and imaging cytometry for healthy controls were 75.0% and 81.3%, respectively. Our immuno-magnetic beads have very low auto-fluorescence, so they could be useful for fluorescent analysis, such as fluorescent immunochemical staining. In the future, these novel immuno-magnetic beads could be used for cytological study.