Appl1, Sortilin and Syndecan-1 immunohistochemistry on intraductal carcinoma of the prostate provides evidence of retrograde spread

Altered expression of vesicular trafficking machinery in prostate cancer affects lysosomal dynamics and provides insight into the underlying biology and disease progression

BACKGROUND

This study focuses on the role of lysosomal trafficking in prostate cancer, given the essential role of lysosomes in cellular homoeostasis.

METHODS

Lysosomal motility was evaluated using confocal laser scanning microscopy of LAMP-1-transfected prostate cells and spot-tracking analysis. Expression of lysosomal trafficking machinery was evaluated in patient cohort databases and through immunohistochemistry on tumour samples. The roles of vesicular trafficking machinery were evaluated through over-expression and siRNA. The effects of R1881 treatment on lysosome vesicular trafficking was evaluated by RNA sequencing, protein quantification and fixed- and live-cell microscopy.

RESULTS

Altered regulation of lysosomal trafficking genes/proteins was observed in prostate cancer tissue, with significant correlations for co-expression of vesicular trafficking machinery in Gleason patterns. The expression of trafficking machinery was associated with poorer patient outcomes. R1881 treatment induced changes in lysosomal distribution, number, and expression of lysosomal vesicular trafficking machinery in hormone-sensitive prostate cancer cells. Manipulation of genes involved in lysosomal trafficking events induced changes in lysosome positioning and cell phenotype, as well as differential effects on cell migration, in non-malignant and prostate cancer cells.

CONCLUSIONS

These findings provide novel insights into the altered regulation and functional impact of lysosomal vesicular trafficking in prostate cancer pathogenesis.

Reinterpretation of prostate cancer pathology by Appl1, Sortilin and Syndecan-1 biomarkers

The diagnosis of prostate cancer using histopathology is reliant on the accurate interpretation of prostate tissue sections. Current standards rely on the assessment of Haematoxylin and Eosin (H&E) staining, which can be difficult to interpret and introduce inter-observer variability. Here, we present a digital pathology atlas and online resource of prostate cancer tissue micrographs for both H&E and the reinterpretation of samples using a novel set of three biomarkers as an interactive tool, where clinicians and scientists can explore high resolution histopathology from various case studies. The digital pathology prostate cancer atlas when used in conjunction with the biomarkers, will assist pathologists to accurately grade prostate cancer tissue samples.

Exploring the role of sporadic BRAF and KRAS mutations during colorectal cancer pathogenesis: A spotlight on the contribution of the endosome-lysosome system

The highly heterogenous nature of colorectal cancer can significantly hinder its early and accurate diagnosis, eventually contributing to high mortality rates. The adenoma-carcinoma sequence and serrated polyp-carcinoma sequence are the two most common sequences in sporadic colorectal cancer. Genetic alterations in adenomatous polyposis coli (APC), v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) and tumour protein 53 (TP53) genes are critical in adenoma-carcinoma sequence, whereas v-Raf murine sarcoma viral oncogene homolog B (BRAF) and MutL Homolog1 (MLH1) are driving oncogenes in the serrated polyp-carcinoma sequence. Sporadic mutations in these genes contribute differently to colorectal cancer pathogenesis by introducing distinct alterations in several signalling pathways that rely on the endosome-lysosome system. Unsurprisingly, the endosome-lysosome system plays a pivotal role in the hallmarks of cancer and contributes to specialised colon function. Thus, the endosome-lysosome system might be distinctively influenced by different mutations and these alterations may contribute to the heterogenous nature of sporadic colorectal cancer. This review highlights potential connections between major sporadic colorectal cancer mutations and the diverse pathogenic mechanisms driven by the endosome-lysosome system in colorectal carcinogenesis.

Altered endosomal-lysosomal biogenesis in melanoma

Cutaneous melanoma is the deadliest form of skin neoplasm and its high mortality rates could be averted by early accurate detection. While the detection of melanoma is currently reliant upon melanin visualisation, research into melanosome biogenesis, as a key driver of pathogenesis, has not yielded technology that can reliably distinguish between atypical benign, amelanotic and melanotic lesions. The endosomal-lysosomal system has important regulatory roles in cancer cell biology, including a specific functional role in melanosome biogenesis. Herein, the involvement of the endosomal-lysosomal system in melanoma was examined by pooled secondary analysis of existing gene expression datasets. A set of differentially expressed endosomal-lysosomal genes was identified in melanoma, which were interconnected by biological function. To illustrate the protein expression of the dysregulated genes, immunohistochemistry was performed on samples from patients with cutaneous melanoma to reveal candidate markers. This study demonstrated the dysregulation of Syntenin-1, Sortilin and Rab25 may provide a differentiating feature between cutaneous melanoma and squamous cell carcinoma, while IGF2R may indicate malignant propensity in these skin cancers.