BACKGROUND: Primary renal cell carcinoma (RCC) is the most frequent kidney cancer. In renal transplant patients, RCC more commonly arise in the native kidneys, whereas allograft involvement has been just occasionally reported. In these latter cases, a graft origin of tumor cells should be considered and other recipients from the same donor should be investigated. So far, genetic studies to trace the origin of cancer cells have always confirmed the donor origin of these tumors. METHODS: A 58-year-old man developed an RCC in the grafted kidney 14 years after transplantation. Histologic and immunohistochemical studies diagnosed a clear cell RCC with sarcomatoid changes. A nine microsatellite DNA assay was used to compare renal tumor cells with donor's (graft parenchyma) and recipient's (lymph nodes and blood) cells. RESULTS: Of the nine microsatellites analyzed, four turned out to be noninformative and the other five (D1S2734, D1S214, D1S199, D19S219, and Humara) showed different band profiles in donor's and recipient's cells DNA. Tumor and blood profile matching confirmed the recipient origin of neoplastic cells. CONCLUSIONS: We report the first case of a grafted-kidney RCC whose recipient's cell origin has been proved by microsatellite analysis. An origin from the recipient's kidney or bone marrow stem cells is proposed as the more plausible hypothesis.

In recent years, an increasing number of studies have shown that elevated expression of cyclin dependent kinase (Cdk5) contributes to the oncogenic initiation and progression of many types of cancers. In this study, we investigated the expression pattern of Cdk5 in colorectal cancer (CRC) cell lines and in a large number of tumor samples in order to evaluate its relevance in this pathogenesis and possible use as a prognostic marker. We found that Cdk5 is highly expressed and activated in CRC cell lines and that silencing of the kinase decreases their migration ability. In tumor tissues, Cdk5 is overexpressed compared to normal tissues due to a copy number gain. In patients with localized disease, we found that high Cdk5 levels correlate with poor prognosis, while in the metastatic setting, this was only the case for patients receiving an oxaliplatin-based treatment. When exploring the Cdk5 levels in the consensus molecular subtypes (CMS), we found the lowest levels in subtype 1, where high Cdk5 again was associated with a poorer prognosis. In conclusion, we confirm that Cdk5 is involved in CRC and disease progression and that it could serve as a prognostic and predictive biomarker in this disease.

One of the most striking epigenetic alterations that occurs at the level of the nucleosome is the complete exchange of the canonical H2A histones for the macroH2A variant. Here, we provide insight into the poorly recognized function of macroH2A in transcriptional activation and demonstrate its relevance in embryonic and adult stem cells. Knockdown of macroH2A1 in mouse embryonic stem (mES) cells limited their capacity to differentiate but not their self-renewal. The loss of macroH2A1 interfered with the proper activation of differentiation genes, most of which are direct target genes of macroH2A. Additionally, macroH2A1-deficient mES cells displayed incomplete inactivation of pluripotency genes and formed defective embryoid bodies. In vivo, macroH2A1-deficient teratomas contained a massive expansion of malignant, undifferentiated carcinoma tissue. In the heterogeneous culture of primary human keratinocytes, macroH2A1 levels negatively correlated with the self-renewal capacity of the pluripotent compartment. Together these results establish macroH2A1 as a critical chromatin component that regulates the delicate balance between self-renewal and differentiation of embryonic and adult stem cells.

Purpose: This work addresses the detection of Helicobacter pylori (H. pylori) in histological images with immunohistochemical staining. This analysis is a time demanding task, currently done by an expert pathologist that visually inspects the samples. Given the effort required to localise the pathogen in images, a limited number of annotations might be available in an initial setting. Our goal is to design an approach that, using a limited set of annotations, is capable of obtaining results good enough to be used as a support tool. Methods: We propose to use autoencoders to learn the latent patterns of healthy patches and formulate a specific measure of the reconstruction error of the image in HSV space. ROC analysis is used to set the optimal threshold of this measure and the percentage of positive patches in a sample that determines the presence of H. pylori. Results: Our method has been tested on an own database of 245 Whole Slide Images (WSI) having 117 cases without H. pylori and different density of the bacteria in the remaining ones. The database has 1211 annotated patches, with only 163 positive patches. This dataset of positive annotations was used to train a baseline thresholding and an SVM using the features of a pre-trained RedNet18 and ViT models. A 10-fold cross-validation shows that our method has better performance with 91% accuracy, 86% sensitivity, 96% specificity and 0.97 AUC in the diagnosis of H. pylori. Conclusion: Unlike classification approaches, our shallow autoencoder with threshold adaptation for the detection of anomalous staining is able to achieve competitive results with a limited set of annotated data. This initial approach is good enough to be used as a guide for fast annotation of infected patches.

Abstract Background Reliable biomarkers for precision medicine in metastatic colorectal cancer (mCRC) are needed. Blood biomarkers like chemokines may offer insights into overall tumor burden, yet, few prospective studies explore chemokine dynamics during treatment. This study investigates the behavior of a chemokine panel in mCRC patients during first-line oxaliplatin-based treatment, aiming to identify predictive and prognostic biomarkers. Methods Blood from oxaliplatin-treated mCRC patients was collected at three time points: before treatment (PRET), at response evaluation (EVAR), and at disease progression or last follow-up (LFUP). A custom 11-chemokine panel assessed serum chemokine levels by Luminex®, correlating them with treatment response, overall survival (OS), and progression-free survival (PFS) using the Cox proportional hazards models with the inverse probability weighting (IPW) approach. Additionally, immune system-associated gene expression was studied by Nanostring® in 15 primary tumor samples and correlated with CXCL13 expression, OS, and PFS. In silico analysis of 119 liver metastases from CRC patients, post neoadjuvant oxaliplatin-based treatment or untreated, evaluated CXCL13 expression’s correlation with immune cell infiltration, tertiary lymphoid structure (TLS) presence, OS, and PFS. Additionally, CXCL13 dynamics was studied by ELISA in 36 mCRC patients from the METIMMOX study control arm. Results Responders exhibited increased CXCL13 at EVAR, contrasting with non-responders whose levels decreased at EVAR and LFUP. Increased CXCL13 independently associated with improved PFS (median 14.5 vs. 8.9 months; HR = 0.34, p = 0.003) and OS (median 39.7 vs. 15.3 months; HR = 0.34, p = 0.003). CXCL13 expression correlated positively with an immunogenic tumor microenvironment, increased B cells, T cells (mainly CD8+) and enhanced OS. In silico , higher CXCL13 expression associated significantly with increased immune infiltration and improved OS. High CXCL13 expression was linked to the presence of TLSs, also associated with enhanced OS, especially in neoadjuvant-treated patients. Similar trends were obtained using the METIMMOX cohort. Conclusion The increase of CXCL13 levels in peripheral blood and its association with the formation of TLSs within the metastatic lesions, emerges as a potential biomarker indicative of the therapeutic efficacy in metastatic CRC patients undergoing oxaliplatin-based treatment.

This work addresses the detection of Helicobacter pylori a bacterium classified since 1994 as class 1 carcinogen to humans. By its highest specificity and sensitivity, the preferred diagnosis technique is the analysis of histological images with immunohistochemical staining, a process in which certain stained antibodies bind to antigens of the biological element of interest. This analysis is a time demanding task, which is currently done by an expert pathologist that visually inspects the digitized samples. We propose to use autoencoders to learn latent patterns of healthy tissue and detect H. pylori as an anomaly in image staining. Unlike existing classification approaches, an autoencoder is able to learn patterns in an unsupervised manner (without the need of image annotations) with high performance. In particular, our model has an overall 91% of accuracy with 86\% sensitivity, 96% specificity and 0.97 AUC in the detection of H. pylori.

<p>Analysis of TAGLN expression and dasatinib target interaction in cancer cell lines</p>

Lymph node (LN) metastasis is an important prognostic factor in colorectal cancer (CRC). We aimed to demonstrate the presence of lymphatic vessels (LV) in the mucosa of in-situ (pTis) CRC, and of detectable tumour burden in regional LNs. This is an observational retrospective study of 39 surgically resected in situ CRCs. The number of LVs was evaluated in both pTis and normal mucosa using D2-40 immunostains. All LNs were assessed with both H&E and the One Step Nucleic Acid Amplification (OSNA) assay, and the results were correlated with clinicopathological features. D2-40 immunohistochemisty revealed LVs in the lamina propria of all pTis CRC (100%), being absent in normal mucosa. A median of 16 LNs were freshly dissected per patient, and all cases were pN0 with H&E. Molecular LN analysis with OSNA revealed the presence of low amounts of tumour burden in 11/39 (28%) cases (range 400 to 4270 CK19 mRNA copies/µL), which had no clinical consequences. This study demonstrates the presence of LVs in the lamina propria in 100% of pTis CRC, as well as the presence of low amounts of tumour burden in regional LNs, only detected by molecular methods. Given the prognostic value of LN tumour burden, its molecular quantification may help a patient's clinical management.

AIMS: Pathological evaluation of colorectal carcinoma (CRC) diagnosed at stage pT1 is challenging. Nevertheless, it is crucial for treatment guiding and to determine the patient's prognosis. This study aimed to assess the interobserver variability in the histopathological evaluation of pT1 CRC. METHODS AND RESULTS: A retrospective multicentre pT1 CRC cohort study was designed (EpiT1 consortium). A task force comprising 20 experienced pathologists conducted the histopathological evaluation using digitalized haematoxylin-eosin (H&E) slides. A pilot study was performed with 10 cases, and afterwards, a consensus meeting was held to assess interobserver variability. Then, a concordance study was performed by assessing 70 new pT1 CRC cases. We used percentage agreement and Gwet's Agreement Coefficient 1 for categorical variables, and intraclass correlation coefficient (ICC) for continuous variables. In the pilot study, histological grade and perineural invasion (PNI) demonstrated 100% agreement, with good concordance for lymphovascular invasion (LVI), tumour budding (TB), poorly differentiated clusters (PDC) and margin assessment. The concordance study showed high agreement (≥90%) on histological grade, PDC, PNI and LVI. Submucosal invasion depth showed excellent reliability in the concordance study (ICC = 0.97). Notably, in both studies, the agreement of PDC was higher than for TB. Lower concordance was observed on stromal lymphocytes and the status of muscularis mucosae. CONCLUSIONS: Our results emphasize the need for standardization in evaluating pT1 CRC to improve the concordance among pathologists, and the precision of digital measurements. Moreover, the addition of PDC assessment in pT1 CRC diagnostic guidelines could help to improve the accuracy of risk stratification and reliably predict prognosis.