Toll-like receptors 1-9 in small bowel neuroendocrine tumors-Clinical significance and prognosis

Toll-like receptors (TLRs) are pattern recognition receptors of the innate immunity. TLRs are known to mediate both antitumor effects and tumorigenesis. TLRs are abundant in many cancers, but their expression in small bowel neuroendocrine tumors (SB-NETs) is unknown. We aimed to characterize the expression of TLRs 1-9 in SB-NETs and lymph node metastases and evaluate their prognostic relevance. The present study included 125 patients with SB-NETs, of whom 95 had lymph node metastases, from two Finnish hospitals. Tissue samples were stained immunohistochemically for TLR expression, assessed based on cytoplasmic and nucleic staining intensity and percentage of positively stained cells. Statistical methods for survival analysis included Kaplan-Meier method and Cox regression adjusted for confounding factors. Disease-specific survival (DSS) was the primary outcome. TLRs 1-2 and 4-9 were expressed in SB-NETs and lymph node metastases. TLR3 showed no positive staining. In primary SB-NETs, TLRs 1-9 were not associated with survival. For lymph node metastases, high cytoplasmic TLR7 intensity associated with worse DSS compared to low cytoplasmic intensity (26.4% vs. 84.9%, p = 0.028). Adjusted mortality hazard (HR) was 3.90 (95% CI 1.07-14.3). The expression of TLRs 1-6 and 8-9 in lymph node metastases were not associated with survival. SB-NETs and their lymph node metastases express cytoplasmic TLR 1-2 and 4-9 and nucleic TLR5. High TLR7 expression in SB-NET lymph node metastases was associated with worse prognosis. The current research has future perspective, as it can help create base for clinical drug trials to target specific TLRs with agonists or antagonists to treat neuroendocrine tumors.

Toll-like receptors 1, 2, 4, 5, and 6 in gastric cancer

Toll-like receptors (TLRs) are expressed on both immune cells and tumor cells, triggering both anti-tumor and pro-tumor responses. Therefore, TLRs have potential as prognostic biomarkers and immunotherapeutic targets. The aim of this study was to investigate TLR1, TLR2, TLR4, TLR5, and TLR6 expression and association with clinicopathological variables and survival in gastric cancer. Immunohistochemical study on cancer specimens from 564 resected gastric cancer patients was performed using tissue microarrays. The association between patient survival and TLR expression was calculated with Cox regression adjusted for confounding factors. Patients with high cytoplasmic TLR2 expression had significantly poorer 5-year survival than the low cytoplasmic TLR2 expression group in multivariate analysis (adjusted HR 1.38, 95% CI 1.11-1.71), and this estimate was similar in intestinal type (adjusted HR 1.33, 95% CI 0.98-1.80) and diffuse type (adjusted HR 1.48, 95% CI 1.06-2.05) histology subgroups. Patients with high cytoplasmic TLR6 expression group had significantly better 5-year survival compared with low cytoplasmic TLR6 expression group in multivariate analysis (adjusted HR 0.74, 95% CI 0.60-0.91). In the subgroup analysis of diffuse type of histology, the 5-year survival was better in high cytoplasmic TLR6 expression group in multivariable analysis (HR 0.62, 95% CI 0.46-0.83). In the intestinal type of histology subgroup, no significant differences between the groups were present. TLR1, TLR4, and TLR5 expression were not associated with 5-year survival. In conclusion, cytoplasmic TLR2 and TLR6 expression seem to have independent prognostic impact in gastric cancer, while TLR1, TLR4, and TLR5 do not.

Optimized detection and segmentation of nuclei in gastric cancer images using stain normalization and blurred artifact removal

Histological analysis with microscopy is the gold standard to diagnose and stage cancer, where slides or whole slide images are analyzed for cell morphological and spatial features by pathologists. The nuclei of cancerous cells are characterized by nonuniform chromatin distribution, irregular shapes, and varying size. As nucleus area and shape alone carry prognostic value, detection and segmentation of nuclei are among the most important steps in disease grading. However, evaluation of nuclei is a laborious, time-consuming, and subjective process with large variation among pathologists. Recent advances in digital pathology have allowed significant applications in nuclei detection, segmentation, and classification, but automated image analysis is greatly affected by staining factors, scanner variability, and imaging artifacts, requiring robust image preprocessing, normalization, and segmentation methods for clinically satisfactory results. In this paper, we aimed to evaluate and compare the digital image analysis techniques used in clinical pathology and research in the setting of gastric cancer. A literature review was conducted to evaluate potential methods of improving nuclei detection. Digitized images of 35 patients from a retrospective cohort of gastric adenocarcinoma at Oulu University Hospital in 1987-2016 were annotated for nuclei (n = 9085) by expert pathologists and 14 images of different cancer types from public TCGA dataset with annotated nuclei (n = 7000) were used as a comparison to evaluate applicability in other cancer types. The detection and segmentation accuracy with the selected color normalization and stain separation techniques were compared between the methods. The extracted information can be supplemented by patient's medical data and fed to the existing statistical clinical tools or subjected to subsequent AI-assisted classification and prediction models. The performance of each method is evaluated by several metrics against the annotations done by expert pathologists. The F1-measure of 0.854 ± 0.068 is achieved with color normalization for the gastric cancer dataset, and 0.907 ± 0.044 with color deconvolution for the public dataset, showing comparable results to the earlier state-of-the-art works. The developed techniques serve as a basis for further research on application and interpretability of AI-assisted tools for gastric cancer diagnosis.

The prognostic role of tumor budding and tumor-stroma ratio in pulmonary metastasis of colorectal carcinoma

OBJECTIVE

To evaluate the prognostic value of tumor budding and tumor-stroma ratio (TSR) in resected pulmonary metastases of colorectal carcinoma (CRC).

METHODS

In total, 106 pulmonary metastasectomies were performed to 74 patients in two study hospitals during 2000-2020. All relevant clinical data were retrospectively collected. Tumor budding based on the International Tumor Budding Consensus Conference recommendations and TSR in the first resected pulmonary metastases and primary tumors were evaluated from diagnostic hematoxylin-eosin-stained histopathological slides.

RESULTS

60 patients (85.7%) had low tumor budding (≤5 buds/field) and 10 patients (14.3%) had high tumor budding (>5 buds/field) in their first pulmonary metastases of CRC. 5-year overall survival rates of pulmonary metastasectomy in low and high total tumor budding were 28.3% and 37.3% (p = 0.387), respectively. 19 patients (27.1%) had low TSR and 51 patients (72.9%) had high TSR. The 5-year overall survival rates were 32.9% in low and 28.6% in high TSR of first pulmonary metastases (p = 0.746). Tumor budding and TSR did not provide prognostic value in Cox multivariate analysis. Tumor budding and TSR in resected pulmonary metastases were not associated with those of the primary tumor.

CONCLUSION

Tumor budding and TSR in the resected pulmonary metastases of CRC showed no statistically significant prognostic value, however, additional well-powered confirmatory studies are needed.

Toll-like receptors 3, 7, 8, and 9 in gastric cancer

Toll-like receptors (TLRs) have been shown to have anti-tumor, pro-tumor, or even dual effects in cancer, and are thus potential prognostic biomarkers and immunotherapeutic targets. The present study aimed to evaluate associations between endosomal TLRs, namely TLR3, TLR7, TLR8, and TLR9, expression and clinicopathological variables and survival in gastric cancer. A total of 564 gastric adenocarcinoma patients were included in this retrospective cohort study. Samples and clinicopathological data were retrieved and organized into tissue microarray blocks. Protein expressions were detected by immunohistochemical staining. The patients were divided into low expression and high expression groups by median values of expression. Cox regression provided hazard ratios (HR) with 95% confidence intervals (CI), adjusted for confounders. Patients with high nuclear TLR3 expression had significantly poorer 5-year survival than the low nuclear TLR3 expression group in the univariable analysis (crude HR 1.31, 95% CI 1.07-1.60). With radically resected patients, poor prognosis was also seen in the multivariable analysis (adjusted HR 1.38, 95% CI 1.08-1.77). Cytoplasmic TLR3, TLR7, TLR8, and TLR9 were not associated with 5-year survival. In conclusion, high nuclear TLR3 expression seems to have prognostic impact in gastric cancer, while TLR7, TLR8, and TLR9 do not.

Tertiary lymphoid structures and gastric cancer prognosis

Tertiary lymphoid structures (TLSs) are part of immune response against cancer. Their high density and high diameter have been shown to be associated with prognosis in different cancer types. The aim of this study was to examine the prognostic significance of TLS density and diameter in gastric cancer and reproducibility of their assessments. TLS densities and maximal TLS diameter were assessed from hematoxylin-eosin (HE) stained slides of 721 surgically treated gastric cancer patients from two hospitals in Finland. Mortality hazard ratios (HRs) for TLS densities and maximal TLS diameter were analyzed. TLS densities and maximal TLS diameter were assessed with moderate interobserver agreement (Cohen's kappa 0.50-0.62). Maximal TLS density was not associated with survival (adjusted HR 0.85, 95% CI 0.70-1.02) and neither was hotspot TLS density (adjusted HR 0.85, 95% CI 0.70-1.02). High maximal TLS diameter was associated with longer survival in overall study population (adjusted HR 0.74, 95% CI 0.61-0.89) and in diffuse type subgroup (adjusted HR 0.65, 95% CI 0.50-0.85). In conclusion, high maximal TLS diameter is associated with improved survival in gastric cancer and can be assessed from HE-stained slides. Its prognostic value might be limited to diffuse histological type.

Toll-like receptor 5 and 8 in hepatocellular carcinoma

Toll-like receptors (TLRs) are components of innate immunity, but also have a role in carcinogenesis. The prognostic value of TLR5 and TLR8 tumor expression was examined in contrast with known risk markers Ki67 and p53. All HCC patients from Oulu University Hospital with available representative tumor sample were included in this study (n = 182). TLR5, TLR8, Ki67, and p53 expression were investigated by immunohistochemistry. The relation between patient survival and TLR, Ki67, and p53 expression was calculated with Cox regression adjusted for confounding factors. TLR5 cytoplasm intensity was associated with 5-year overall (strong 0.0% vs weak 23.4%, p < 0.001) and disease-specific (strong 0.0% vs weak 34.9%, p < 0.001) survival. TLR5 nuclei percentage was associated with poor 5-year disease-specific survival (high 16.3% vs low 31.5%, p = 0.022). In adjusted analysis, strong TLR5 cytoplasm intensity was an independent risk factor for poor 5-year overall (adjusted HR 1.88, 95% CI 1.26-2.81) and disease-specific (adjusted HR 2.00, 95% CI 1.27-3.15) survival. High Ki67 and p53 expression associated with 5-year overall- and disease-specific survival. TLR8 was not associated with patient survival. This study suggests that TLR5 expression is independently prognostic in HCC with similar point estimate as previously known p53.

Monocarboxylate Transporters 1 and 4 and MTCO1 in Gastric Cancer

Simple Summary

The expression of monocarboxylate transporters (MCTs) are reported in a variety of cancers and suggested as a therapeutic target for cancer treatment. However, previous study results in gastric cancer are contradictory. In this study, we evaluated the expression of MCT1, MCT4, and Mitochondrial cytochrome c oxidase (MTCO1) and their association with clinicopathological parameters and prognostic significance in a cohort of 568 surgically treated gastric cancer patients. The results suggest that monocarboxylate transporters and MTCO1 are associated with gastric cancer progression but have no independent prognostic relevance.

Abstract

Background: Monocarboxylate transporters (MCTs) appear to play an important role in tumor development and aggressiveness. The present study aimed to evaluate associations between cytoplasmic MCT1, MCT4, and mitochondrial cytochrome c oxidase (MTCO1) expression and clinicopathological variables or survival in gastric cancer. Material and methods: A total of 568 gastric adenocarcinoma patients were included in this retrospective cohort study. Protein expressions were detected by immunohistochemical staining. The patients were divided into low expression and high expression groups by median value. The Chi-squared test was used to compare categorical variables. The T-test was used to compare continuous variables. Expressions were analyzed in relation to 5-year survival and overall survival. Cox regression provided HRs and 95% CIs, adjusted for confounders. Results: High cytoplasmic MCT1 expression was associated statistically significantly with higher T-class (p = 0.020). High cytoplasmic MCT4 expression was associated statistically significantly with positive lymph node status (p = 0.005) and was more common in Lauren’s intestinal type (p < 0.001). Low cytoplasmic MTCO1 expression was associated statistically significantly with positive distant metastases (p = 0.030), and high cytoplasmic MTCO1 expression was associated more often with intestinal type (p = 0.044). However, MCT1, MCT4, and MTCO1 were not associated with survival. Conclusions: Monocarboxylate receptors seem to be associated with gastric cancer progression but have no independent prognostic relevance.

Tumour budding and tumour-stroma ratio in hepatocellular carcinoma

BACKGROUND

Tumour budding and low tumour-stroma ratio (TSR) are associated with poor prognosis in some cancers, but their value in Western hepatocellular carcinoma is unclear. The prognostic value of tumour budding and TSR in hepatocellular carcinoma was examined.

METHODS

Some 259 hepatocellular carcinoma patients treated in Oulu University Hospital 1983-2018 were included in this retrospective cohort study. Tumour budding and TSR were analysed from the haematoxylin- and eosin-stained original diagnostic slides, by dividing patients into bud-negative (0 bud) or bud-positive (≥1 bud) groups, and into high TSR (<50%) and low TSR (≥50%) groups. Surgically treated patients (n = 47) and other treatments (n = 212) were analysed separately. Primary outcomes were overall, and disease-specific 5-year mortality was adjusted for confounding factors.

RESULTS

Surgically treated patients with positive tumour budding had increased 5-year overall (adjusted HR 3.87, 95% CI 1.10-13.61) and disease-specific (adjusted HR 6.17, 95% CI 1.19-31.90) mortality compared with bud-negative patients. In surgically treated patients, TSR had no effect on 5-year overall (adjusted HR 2.03, 95% CI 0.57-7.21) or disease-specific (adjusted HR 3.23, 95% CI 0.78-13.37) mortality. No difference in survival related to tumour budding and TSR in non-surgically treated patients was observed.

CONCLUSIONS

Tumour budding is a prognostic factor in surgically treated hepatocellular carcinoma.