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.

Metalloproteinase 9 immunostaining profile is positively correlated with tumor grade, extraprostatic extension and biochemical recurrence in prostate cancer.

Metastasis is the main problem in the treatment of prostate cancer (PCa), and for it to occur, proteolytic enzymes must remodel the extracellular matrix (ECM) surrounding the tumor. The most important group of enzymes with this action include the matrix metalloproteinases (MMPs), which act on various substrates cleaving ECM components. The present study aimed to evaluate the protein immunostaining profiles of matrix metalloproteinase 2 (MMP-2) and 9 (MMP-9) in PCa Brazilian patients using the indirect immunohistochemical methodology. The tissue samples (n = 178), 60 from malignant tumor, 58 from adjacent non-tumor, and 60 from ECM, were evaluated according to the immunostaining intensity. The malignant tumor cytoplasmic MMP-2 immunostaining was more intense than in ECM (p = 0.001), but it did not correlate with any clinical-pathological parameter. The MMP-9 staining was similar in tumor cytoplasm, adjacent non-tumor cytoplasm and ECM, but showed significant positive correlations with ISUP grade (p = 0.044; Tau=0.249), extraprostatic extension (p = 0.025; Tau=0.309), and biochemical recurrence (p = 0.048; Tau=0.306). A significant positive correlation was also observed between MMP-2 and MMP-9 in all cell compartments analyzed. Although further research is warranted to elucidate the precise mechanisms underlying these observations, our findings suggest MMP-9 as a promising candidate marker for tissue invasion that could be used in predicting the progression and prognosis of PCa.

Allelic variants and immunostaining profile in CXCL12/CXCR4 axis: An investigation of association with prognosis in prostate cancer.

Prostate cancer (PCa) is the malignant neoplasm that most commonly affects men and is an important cause of death. It can be detected by changes in serum levels of Prostate Specific Antigen (PSA) and digital rectal examination, but often symptoms do not appear until advanced stages and metastases. The C-X-C Motif Chemokine Ligand 12/C-X-C Motif Chemokine Receptor 4 (CXCL12/CXCR4) axis acts in cell migration and may be involved in the metastatic process. In this context, the aim of this study was to evaluate the allelic variants rs1801157 (CXCL12) and rs2228014 (CXCR4) and the immunostaining of CXCR4 protein as candidates for prognostic markers in PCa. Samples (n = 60) were divided according to prognostic parameters (with and without metastasis at diagnosis) in tree groups: better prognosis, worse prognosis with metastasis at diagnosis and worse prognosis without metastasis at diagnosis, and immunostaining was evaluated by indirect immunohistochemistry, considering tumoral and adjacent tissues from the same patient (n = 120). A significant association was found between the C allele of rs2228014 (CXCR4) and the extraprostatic extension. For CXCR4 immunostaining a weak labeling and a cytoplasmic localization predominated, as well as a significant difference between malignant versus adjacent tissue, with higher protein expression in the malignant tissue. A significant association was found between CXCR4 tumor immunostaining with TNM staging (T2b-T2c) and PSA level (> 20 ng/mL). None of the allelic variants affected CXCR4 immunostaining. Prognostic groups did not differ in allelic variant frequency or immunostaining profile. Findings suggest that CXCR4 receptor may be one of the ways to worsen the prognosis of prostatic cancer.

Tissue immunostaining of candidate prognostic proteins in metastatic and non-metastatic prostate cancer.

PURPOSE: Prostate cancer (PCa) lacks specific markers capable of distinguishing aggressive tumors from those with indolent behavior. Therefore, the aim of this study was to evaluate the immunostaining of candidate proteins (PTEN, AKT, TRPM8, and NKX3.1) through the immunohistochemistry technique (IHC) on patients with metastatic and non-metastatic PCa. METHODS: Tissues from 60 patients were divided into three groups categorized according to prognostic parameters: better prognosis (n = 20), worse prognosis (n = 23), and metastatic (n = 17). Immunostaining was analyzed by a pathologist and staining classifications were considered according to signal intensity: (0) no staining, (+) weak, and (++ and +++) intermediate to strong. RESULTS: AKT protein was associated (p = 0.012) and correlated (p = 0.014; Tau = - 0.288) with the prognostic groups. The immunostaining for TRPM8 (p = 0.010) and NKX3.1 (p = 0.003) proteins differed between malignant tumor and non-tumoral adjacent tissue as well as for proteins in cellular locations (nucleus and cytoplasm). TRPM8 was independently associated with the ISUP grade ≥ 4 (p = 0.024; OR = 8.373; 95% CI = 1.319-53.164). The NKX3.1 showed positive and predominantly strong immunostaining in all patients in both tumoral and non-tumoral adjacent tissues. All metastatic samples had positive immunostaining, with strong intensity for NKX3.1 (p = 0.021; Tau = - 0.302). In the non-metastatic group, this strong protein staining was not observed in any patients. CONCLUSION: This study confirmed that NKX3.1 is highly specific for prostate tissue and indicated that NKX3.1, AKT, and TRPM8 may be candidate markers for prostate cancer prognosis.