Tumor-Stroma Ratio is a Promising Prognostic Classifier in Oropharyngeal Cancer

Tumor budding and lymphovascular invasion as prognostic factors in p16-positive oropharyngeal squamous cell carcinomas

BACKGROUND

We aimed to validate the prognostic significance of tumor budding (TB) in p16-positive oropharyngeal squamous cell carcinomas (OPSCC).

METHODS

We analyzed digitized H&E-stained slides from a multicenter cohort of five large university centers consisting of n = 275 cases of p16-positive OPSCC. We evaluated TB along with other histological parameters (morphology, tumor-stroma-ratio, lymphovascular invasion (LVI), perineural invasion) and calculated survival outcomes using both univariate and multivariate analyses.

RESULTS

TB was identified as an independent prognostic parameter, with TB-high cases showing inferior outcomes in univariate (HR: 3.08, 95%-CI: 1.71-5.54) and multivariate analyses (HR: 4.03, 95%-CI: 1.65-9.83). Similarly, LVI remained an independent prognostic factor (HR: 3.00, 95%-CI: 1.22-7.38). A combined classification including TB and LVI stratified cases into low-, intermediate- and high-risk categories. We could not detect correlations between TB and the number of lymph node metastases or between TB and an extracapsular extension of lymph node metastases.

CONCLUSIONS

In addition to LVI, we could identify TB as an independent prognostic factor in p16-positive OPSCC in this multicenter study cohort. Thus, evaluating TB along with LVI in a combined scheme for prognostication might help to establish a more personalized treatment regimen for patients with p16-positive OPSCC.

Fibroblasts regulate the transcriptional signature of human papillomavirus-positive keratinocytes

Persistent human papillomavirus (HPV) infection is necessary but insufficient for viral oncogenesis. Additional contributing co-factors, such as immune evasion and viral integration have been implicated in HPV-induced cancer progression. It is widely accepted that HPV + keratinocytes require co-culture with fibroblasts to maintain viral DNA as episomes. How fibroblasts regulate viral episome maintenance is a critical knowledge gap. Here we present comprehensive RNA sequencing and proteomic analysis demonstrating that coculture with fibroblasts is supportive of the viral life cycle, and is confirmatory of previous observations. Novel observations suggest that errors in "cross-talk" between fibroblasts and infected keratinocytes may regulate HPV integration and drive oncogenic progression. Our co-culture models offer new insights into HPV-related transformation mechanisms.

One novel transfer learning-based CLIP model combined with self-attention mechanism for differentiating the tumor-stroma ratio in pancreatic ductal adenocarcinoma

PURPOSE

To develop a contrastive language-image pretraining (CLIP) model based on transfer learning and combined with self-attention mechanism to predict the tumor-stroma ratio (TSR) in pancreatic ductal adenocarcinoma on preoperative enhanced CT images, in order to understand the biological characteristics of tumors for risk stratification and guiding feature fusion during artificial intelligence-based model representation.

MATERIAL AND METHODS

This retrospective study collected a total of 207 PDAC patients from three hospitals. TSR assessments were performed on surgical specimens by pathologists and divided into high TSR and low TSR groups. This study developed one novel CLIP-adapter model that integrates the CLIP paradigm with a self-attention mechanism for better utilizing features from multi-phase imaging, thereby enhancing the accuracy and reliability of tumor-stroma ratio predictions. Additionally, clinical variables, traditional radiomics model and deep learning models (ResNet50, ResNet101, ViT_Base_32, ViT_Base_16) were constructed for comparison.

RESULTS

The models showed significant efficacy in predicting TSR in PDAC. The performance of the CLIP-adapter model based on multi-phase feature fusion was superior to that based on any single phase (arterial or venous phase). The CLIP-adapter model outperformed traditional radiomics models and deep learning models, with CLIP-adapter_ViT_Base_32 performing the best, achieving the highest AUC (0.978) and accuracy (0.921) in the test set. Kaplan-Meier survival analysis showed longer overall survival in patients with low TSR compared to those with high TSR.

CONCLUSION

The CLIP-adapter model designed in this study provides a safe and accurate method for predicting the TSR in PDAC. The feature fusion module based on multi-modal (image and text) and multi-phase (arterial and venous phase) significantly improves model performance.

Prognostic Significance of Tumor-Stroma Ratio (TSR) in Head and Neck Squamous Cell Carcinoma: Systematic Review and Meta-Analysis

The management of head and neck squamous cell carcinoma (HNSCC) relies heavily on TNM staging and WHO histologic grading; however, in recent years, the analysis of prognostic markers expressed in the tumor stroma has gained attention. The tumor-stroma ratio (TSR) quantifies the proportion of tumor tissue relative to the surrounding stromal tissue; it is assessed with the percentage of stromal tissue within the tumor area, with a cutoff point of 50% being widely used to discriminate high-stroma cancer. In this systematic review and meta-analysis, we investigated the potential prognostic role of the TSR in HNSCC. After a literature screening, 24 studies dealing with the TSR and survival outcomes were included. The TSR showed a significant association with overall survival (OS) in both unadjusted and adjusted measures (RR 2.04, CI 1.57-2.65, p < 0.01; HR 2.36 CI 1.89-2.94, p < 0.00001), with an even stronger prognostic potential in oral cavity/oral tongue cancers (RR 2.44 CI 1.84-3.22, p < 0.00001). The TSR also showed prognostic value when dealing with cancer-specific survival and was associated with a reduction in disease-free survival (DFS). In particular, the TSR also retained its prognostic role in terms of DFS when specifically considering early-stage cancers in both unadjusted and adjusted analyses (RR 1.81 CI 1.57-2.10, p < 0.00001; HR 2.09 CI 1.58-2.76, p < 0.00001). Therefore, we conclude that the TSR is a reliable prognostic marker that is easy to assess in routine histological slides and can be effectively implemented in the routine evaluation of HNSCC.

A predictive model and rapid multi-dynamic algorithm developed based on tumor-stroma percentage in gastric cancer: a retrospective, observational study

Background

Tumor-stroma percentage (TSP) is a prognostic risk factor in numerous solid tumors. Despite this, the prognostic significance of TSP in gastric cancer (GC) remains underexplored. Through the development of a personalized predictive model and a semi-automatic identification system, our study aimed to fully unlock the predictive potential of TSP in GC.

Methods

We screened GC patients from Shanghai General Hospital (SGH) between 2012 and 2019 to develop and validate a nomogram. Univariate and multivariate Cox proportional hazards regression analyses were employed to identify independent prognostic factors influencing the prognosis for GC patients. The nomogram was further validated externally by using a cohort from Bengbu Medical College (BMC). All patients underwent radical gastrectomy, with those diagnosed with locally advanced GC receiving adjuvant chemotherapy. The primary outcome measured was overall survival (OS). The semi-automatic identification of the TSP was achieved through a computer-aided detection (CAD) system, denoted as TSP-cad, while TSP identified by pathologists was labeled as TSP-visual.

Results

A total of 813 GC patients from SGH and 59 from BMC were enrolled in our study. TSP-visual was identified as an adverse prognostic factor for OS in GC and was found to be associated with pathological Tumor Node Metastasis staging system (pTNM) stage, T stage, N stage, perineural invasion (PNI), lymphovascular invasion (LVI), TSP-visual, tumor size, and other factors. Multivariate Cox regression using the training cohort revealed that TSP-visual (hazard ratio [HR], 2.042; 95% confidential interval [CI], 1.485-2.806; P < 0.001), N stage (HR, 2.136; 95% CI, 1.343-3.397; P = 0.010), PNI (HR , 1.791; 95% CI, 1.270-2.526; P = 0.001), and LVI (HR, 1.482; 95% CI, 1.021-2.152; P = 0.039) were independent predictors. These factors were incorporated into a novel nomogram, which exhibited strong predictive accuracy for 5-year OS in the training, internal validation, and external validation cohorts (area under the curve = 0.744, 0.759, and 0.854, respectively). The decision curve analysis of the nomogram and concordance indexes across the three cohorts outperformed the traditional pTNM (P < 0.05). Additionally, TSP-cad assessment using a rapid multi-dynamic algorithm demonstrated good agreement with TSP-visual.

Conclusions

The novel nomogram based on TSP could effectively identify individuals at risk of a poor prognosis among patients with GC. TSP-cad is anticipated to enhance the evaluation process of TSP.

Fibroblasts Regulate the Transformation Potential of Human Papillomavirus-positive Keratinocytes

Persistent human papillomavirus (HPV) infection is necessary but insufficient for viral oncogenesis. Additional contributing co-factors, such as immune evasion and viral integration have been implicated in HPV-induced cancer progression. It is widely accepted that HPV+ keratinocytes require co-culture with fibroblasts to maintain viral episome expression, yet the exact mechanisms for this have yet to be elucidated. Here we present comprehensive RNA sequencing and proteomic analysis demonstrating that fibroblasts not only support the viral life cycle, but reduce HPV+ keratinocyte transformation. Our co-culture models offer novel insights into HPV-related transformation mechanisms.

Tumor-matched and unmatched cancer associated fibroblasts exhibit differential effect on proliferation and FMOD and MMP9 gene expression in head and neck squamous cell carcinoma cells when cocultured in spheroids

BACKGROUND

Cancer-associated fibroblasts (CAFs) are the major cellular component of the tumor microenvironment and are known to affect tumor growth and response to various treatments. This study was undertaken to investigate the crosstalk between tumor-matched or unmatched CAFs and head and neck squamous cell carcinoma (HNSCC) cells regarding tumor growth and treatment response.

METHODS

Three HNSCC cell lines (LK0412, LK0902 and LK0923), were cocultured in 2D or in 3D with their tumor-matched CAFs, site matched CAFs from other tumors or normal oral fibroblasts (NOFs). Cell proliferation was assessed as the amount of Ki67 positive cells/ spheroid area in formalin-fixed- paraffin-embedded 3D spheroids stained with Ki67 antibody. Viability after seven days of cisplatin treatment was measured with CellTiter-Glo 3D Viability Assay. The mRNA expression of CAF-associated markers (ACTA2, COL1A2, FAP, PDGFRα, PDGFRβ, PDPN, POSTN and S100A4) in CAFs before and after coculture with tumor cells as well as mRNA expression of CAF-induced genes (MMP1, MMP9 and FMOD) in tumor cells separated from CAFs after co-culture was measured with RT-qPCR. The expression of selected protein biomarkers was validated with immunohistochemistry based on previous mRNA expression results.

RESULTS

The proliferation of the LK0412 and LK0902 tumor spheroids varied significantly when cocultured with different CAFs and NOFs as shown by Ki-67 positive cells. RT‒qPCR analysis revealed different molecular profile of the analyzed HNSCC-derived CAFs concerning the expression of CAF-associated markers. The interaction between CAFs and HNSCC cells was more pronounced after coculture with unmatched CAFs as shown by changes in mRNA expression pattern of CAF-specific markers. Additionally, the unmatched CAFs significantly upregulated the mRNA expression of MMP1, MMP9 and FMOD in tumor cells compared to tumor-matched CAFs.

CONCLUSION

Our results indicate that tumor-matched CAFs are unique for each tumor and affect the proliferation and the gene/protein expression of tumor cells in a distinct manner. The interaction between tumor unmatched CAFs and HNSCC cells in the tumor spheroids is associated with significant changes in the mRNA expression of CAF-specific markers and significant increases in FMOD and MMP9 in tumor cells compared to when cocultured with tumor-matched CAFs. Taken together, our results show how important the selection of CAFs is to get a reliable in vitro model that mimics the patients' tumor.

Prognostic Significance of Tumor-associated Stroma in Nasopharyngeal Carcinoma: A Multicenter Study

Assessment of tumor-associated stroma has shown a reliable prognostic value in recent research. We evaluated the prognostic value of tumor-stroma ratio (TSR) in a large multicenter cohort of nasopharyngeal carcinoma (NPC). We used the conventional hematoxylin and eosin-stained slides of 115 cases of NPC to assess TSR as described in recent guidelines. The amount of tumor-associated stroma was assessed as a percentage and then tumors were classified as stroma-high (>50%) or stroma-low (≤50%). Kaplan-Meier curves, χ 2 test, and Cox regression univariable and multivariable analyses were carried out. A total of 48 (41.7%) tumors were stroma-high and 67 (58.3%) tumors were stroma-low. In the Cox regression multivariable analysis, the tumors categorized as stroma-high were associated with a worse overall survival with a hazard ratio of 2.30 (95% CI: 1.27-4.15, P =0.006) and with poor disease-specific survival (hazard ratio=1.87, 95% CI: 1.07-3.28, P =0.029). The assessment of TSR in NPC is simple and cost-effective, and it has a significant prognostic value. TSR can aid in risk stratification and clinical decision-making in NPC.

Analysis of cells of epithelial, connective tissue and immune differentiation in HPV-positive-, HPV-negative oropharyngeal carcinoma and normal oropharyngeal tissue by immunofluorescence multiplex image cytometry: a preliminary report

BACKGROUND

Epithelial, connective tissue and immune cells contribute in various ways to the pathophysiology of HPV positive (HPV+) and HPV negative (HPV-) oropharyngeal squamous cell carcinoma (OPSCC). We aimed to investigate the abundance of these cell lineages and their coexpression patterns in patients with HPV + and HPV- OPSCC.

METHODS

We used a 4-channel immunofluorescence-microscopy technique for the simultaneous detection of three direct-conjugated antibodies (pancytokeratin, vimentin and CD45/CD18) and DAPI (4',6-Diamidin-2-phenylindole) in formalin fixed paraffin-embedded tissue samples (FFPE) of patients with HPV + and HPV- OPSCC, and of control patients. Image acquisition and analysis were performed with TissueFAXS and StrataQuest (TissueGnostics, Vienna, Austria), respectively, in tumor cell clusters/stroma in OPSCC specimens and epithelial layer/lamina propria in control specimens. Cell populations were created based on antibodies' coexpression patterns. Isotype and positive controls were examined for plausibility.

RESULTS

The proportion of cells of epithelial differentiation in tumor cell clusters was higher in HPV + OPSCC (55%) than in HPV- OPSCC samples (44%). The proportion of connective tissue cells in tumor cell cluster was lower in HPV + OPSCC patients (18%) than in HPV- OPSCC patients (26%). The proportion of immune cells in tumor cell clusters was higher in HPV + OPSCC patients (25%) than in HPV- OPSCC patients (18%). The percentage of anaplastic, potentially de-differentiated cells, was 2% in control patients, and it was higher in HPV- OPSCC (21%) than in HPV + OPSCC samples (6%).

CONCLUSIONS

This study provided the first quantitative data for the abundance of cells of epithelial, connective tissue and immune differentiation, in patients with OPSCC and control patients. The abundance of these different crucial cell populations was consistently originating from the same tissue sample. De-differentiation of tumor cells was higher in HPV- OPSCC than in HPV + OPSCC. In tumor cells clusters, the antitumoral host immune response was higher in HPV + OPSCC than in HPV- OPSCC, whereas the fibroblast response was higher in HPV- OPSCC than in HPV + OPSCC. This study contributed to the understanding of histopathologic differences between HPV + OPSCC and HPV- OPSCC patients.