Deposition of collagen III and alterations in basement membrane integrity as candidate prognostic markers in prostate cancer

The extracellular matrix surrounding the tumor undergoes changes in its organization during the metastasis process. The present study aims to quantify total collagen, collagen I (Col I) and collagen III (Col III), analyze the alignment of collagen fibers and assess the basement membrane integrity in samples from patients with metastatic and non-metastatic prostate cancer. Tissue samples from 60 patients were classified into groups based on prognostic parameters: better prognosis (n = 20), worse prognosis without metastasis (n = 23) and metastatic (n = 17). Picrosirius red with further analysis under polarizing microscope was used to quantify (with validation using immunohistochemistry) and analyze collagen alignment, and Periodic Acid Schiff staining was used to analyze the basement membrane integrity. The Col I/Col III ratio was found to be higher in the metastatic group than in the groups with better prognosis (p = 0.012) and worse prognosis without metastasis (p = 0.018). Basement membrane integrity constitution in malignant tumor tissue differed from that of adjacent non-tumor tissue (p < 0.001). Moreover, the worsening in the tumor tissue integrity was positively correlated with worse prognostic parameters. All in all, absence of Col III and basement membrane integrity might be indicators of poor prognosis in prostate cancer.

Effects of Preservation Methods in the Composition of the Placental and Reflected Regions of the Human Amniotic Membrane

The human amniotic membrane (AM) is emerging as an interesting biomaterial for regenerative medicine due to its biological and mechanical proprieties. The beneficial effects of the AM are probably related to its bioactive factors produced by local cells and stored in the stromal matrix. However, the search for a preservation method capable of preserving AM properties remains a challenge. The aim of this study was to evaluate important features of 2 anatomical regions of the human AM (reflected and placental amnion) after different preservation methods. For this purpose, human placentas were harvested and processed for AM isolation and storage at 2 different conditions: room temperature for 18 h in DMEM (fresh AM) and -80°C in DMEM/glycerol solution for 30 days (cryopreserved AM). After the storage period, the structural integrity of the membrane was assessed by histological and Picrosirius polarization analysis, cellular viability analysis was performed using the MTT assay, and the soluble proteins were quantified with the Qubit Protein Assay Kit. Both preservation protocols reduced the cell viability, mainly in the placental amnion region of the AM, but preserved the morphology of epithelial and stromal layers, as well as the organization and distribution of collagen fibers. There was a reduction in soluble proteins only in fresh AM. Importantly, the cryopreserved AM group presented the same concentration as the control group. In conclusion, the cryopreservation using DMEM/glycerol was ideal for preserving the structural integrity and soluble protein content, indicating the feasibility of this method in preserving AM for its use in regenerative medicine.

Evaluation of angiogenesis, inflammation, and healing on irradiated skin graft with low-level laser therapy in rats (Rattus norvegicus albinus wistar)

The reconstructive techniques have been widely used in Veterinary Medicine. The post-operative adjuvants therapies like the low-level laser therapy (LLLT) are used to decrease inherent complications to reconstructive surgeries. This article purposed to define the LLLT effects on the healing, inflammation, and vascularization of the skin grafts in applicable time intervals to veterinary surgical routine. Forty rats (Rattus norvegicus albinus wistar) were used and each one was submitted to autogenous cutaneous mesh grafting in the interescapular region. The rats were randomly distributed in five groups (G1, G2, G3, G4, and G5) in accordance with the 6 J/cm² or 10 J/cm² dose every 3 or 5 days. These treatments were applied on the skin graft for 15 days. The histochemical evaluation with Picrosirius showed greater expression of collagen type 1 - red in grafts of G5 (p < 0.05), while in G1 did not; the expression of collagen type III - green was not induced by LLLT. The histochemical evaluation with hematoxylin-eosin showed greater numbers of fibroblasts in grafts of G4 (p < 0.05) and less hemorrhage in grafts of G5 (p < 0.05). There was modulation of the inflammatory response in irradiated skin grafts. It is concluded the exhibition of the skin grafts to 6 J/cm² or 10 J/cm² dose every 5 days improved the healing and the modulation of the local inflammation.

Fractal analysis and histomolecular phenotyping provides insights into extracellular matrix remodeling in the developing bovine fetal ovary

Although studies have focused on extracellular matrix (ECM) remodeling during the formation and functioning of adult ovaries, there is no comprehensive understanding of the mechanisms controlling preantral follicle development in fetal bovine ovaries during gestation. Thus, to gain insights into ECM remodeling during initial ovarian development, we used fetal ovaries to quantify the fractal dimension (FD), total collagen, and relative mRNA abundance of genes related to ECM remodeling (COL1A1, COL1A2, COL4A1, MMP2, MMP9, MMP14, TIMP1, and TIMP2). For this, pairs of fetal ovaries were obtained from cows in a local abattoir at days 60, 90, 120, and 150 of gestation; one of each pair was submitted to RNA extraction for target transcript analysis, and the other was used for total collagen and FD evaluation. From day 120 total collagen appeared to occupy a greater area in the fetal ovary. The fractal analysis with picrosirius red staining shows higher at day 150 when compared with that on day 60. On the contrary, we found an inverse pattern when we used the hematoxylin and eosin staining approach. Concerning target gene expression, the relative abundances of COL1A1, COL4A1, MMP2, MMP14, TIMP1, and TIMP2 mRNA were higher on day 150 when compared with that on day 60. We conclude that fractal analysis reflects the morphological changes occurring during structural organization of the fetal ovary and that the expression of genes related to ECM remodeling is modulated throughout gestation in bovine fetal ovaries.