Stromal hyaluronan accumulation is associated with low tumor grade and nodal metastases in pancreatic ductal adenocarcinoma

The Effect of Intratumor Heterogeneity in Pancreatic Ductal Adenocarcinoma Progression and Treatment

BACKGROUND AND OBJECTIVES

Pancreatic cancer is one of the most lethal malignancies. Even though many substantial improvements in the survival rates for other major cancer forms were made, pancreatic cancer survival rates have remained relatively unchanged since the 1960s. Even more, no standard classification system for pancreatic cancer is based on cellular biomarkers. This review will discuss and provide updates about the role of stem cells in the progression of PC, the genetic changes associated with it, and the promising biomarkers for diagnosis.

MATERIALS AND METHODS

The search process used PubMed, Cochrane Library, and Scopus databases to identify the relevant and related articles. Articles had to be published in English to be considered.

RESULTS

The increasing number of studies in recent years has revealed that the diversity of cancer-associated fibroblasts is far greater than previously acknowledged, which highlights the need for further research to better understand the various cancer-associated fibroblast subpopulations. Despite the huge diversity in pancreatic cancer, some common features can be noted to be shared among patients. Mutations involving CDKN2, P53, and K-RAS can be seen in a big number of patients, for example. Similarly, some patterns of genes and biomarkers expression and the level of their expression can help in predicting cancer behavior such as metastasis and drug resistance. The current trend in cancer research, especially with the advancement in technology, is to sequence everything in hopes of finding disease-related mutations.

CONCLUSION

Optimizing pancreatic cancer treatment requires clear classification, understanding CAF roles, and exploring stroma reshaping approaches.

'Two-faces' of hyaluronan, a dynamic barometer of disease progression in tumor microenvironment

Hyaluronan (HA) is a linear polysaccharide consisting of disaccharide units which are the D-glucuronic acid and N-acetyl-D-glucosamine. As the largest component of the extracellular matrix in microenvironment, HA polymers with different molecular weights vary in properties to molecular biology function. High molecular weight HA (HMW-HA) is mainly found in normal tissue or physiological condition, and exhibits lubrication and protection properties due to its good water retention and viscoelasticity. On the other hand, an increase in HA catabolism leads to the accumulation of low molecular weight HA (LMW-HA) under pathological circumstances such as inflammation, pre-cancerous and tumor microenvironment. LMW-HA acts as extracellular signals to enhance tumorigenic and metastatic phenotype, such as energy reprogramming, angiogenesis and extracellular matrix (ECM) remodeling. This review discusses the basic properties of this simplest carbohydrate molecule in ECM with enormous potential, and its regulatory role between tumorigenesis and microenvironmental homeostasis. The extensive discoveries of the mechanisms underlying the roles of HA in various physiological and pathological processes would provide more information for future research in the fields of biomimetic materials, pharmaceutical and clinical applications.

Clinically Relevant Biology of Hyaluronic Acid in the Desmoplastic Stroma of Pancreatic Ductal Adenocarcinoma

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is notorious for its poor outcome. The presence of a dense desmoplastic stroma is a hallmark of this malignancy, and abundant hyaluronic acid (HA) within this stroma is a common feature of PDAC. At the end of 2019, an HA-targeting drug, after initial promise, failed phase 3 clinical trials in PDAC. This failure in the face of such strong evidence for biological importance forces us to turn back to the research and seek a better understanding of HA biology in PDAC. Therefore, in this review, we reexamine what is known about HA biology, the methods used to detect and quantify HA, and the ability of the biological models in which HA has been investigated to recapitulate an HA-rich desmoplastic tumor stroma. The role of HA in PDAC relies on its complex interplay with a range of HA-associated molecules, which have not been as extensively investigated as HA itself. Therefore, using large genomic data sets, we cataloged the abundance and activity in PDAC of molecules that modulate HA synthesis, degradation, protein interactions, and receptor binding. Based on their association with clinical characteristics and individual patient outcomes, we suggest a small number of HA-associated molecules that warrant further investigation as biomarkers and drug targets.

Phyto-targeting the CEMIP Expression as a Strategy to Prevent Pancreatic Cancer Metastasis

INTRODUCTION

Metastasis of primary pancreatic cancer (PC) to adjacent or distant organs is responsible for the poor survival rate of affected individuals. Chemotherapy, radiotherapy, and immunotherapy are currently being prescribed to treat PC in addition to surgical resection. Surgical resection is the preferred treatment for PC that leads to 20% of 5-year survival, but only less than 20% of patients are eligible for surgical resection because of the poor prognosis. To improve the prognosis and clinical outcome, early diagnostic markers need to be identified, and targeting them would be of immense benefit to increase the efficiency of the treatment. Cell migration-inducing hyaluronan-binding protein (CEMIP) is identified as an important risk factor for the metastasis of various cancers, including PC. Emerging studies have pointed out the crucial role of CEMIP in the regulation of various signaling mechanisms, leading to enhanced migration and metastasis of PC.

METHODS

The published findings on PC metastasis, phytoconstituents, and CEMIP were retrieved from Pubmed, ScienceDirect, and Cochrane Library. Computational tools, such as gene expression profiling interactive analysis (GEPIA) and Kaplan-Meier (KM) plotter, were used to study the relationship between CEMIP expression and survival of PC individuals.

RESULTS

Gene expression analysis using the GEPIA database identified a stupendous increase in the CEMIP transcript in PC compared to adjacent normal tissues. KM plotter analysis revealed the impact of CEMIP on the overall survival (OS) and disease-free survival (DFS) among PC patients. Subsequently, several risk factors associated with PC development were screened, and their ability to regulate CEMIP gene expression was analyzed using computational tools.

CONCLUSION

The current review is focused on gathering information regarding the regulatory role of phytocomponents in PC migration and exploring their possible impact on the CEMIP expression.

Hyaluronan heterogeneity in pancreatic ductal adenocarcinoma: Primary tumors compared to sites of metastasis

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive cancers with poor survival. The dense desmoplastic stroma in PDAC contributes to treatment resistance. Among the components comprising the tumor stroma, hyaluronan (HA) has been demonstrated to play a critical role in tumor progression and survival. Previous preliminary studies have suggested differences in HA expression in primary and metastatic foci of PDAC. However, the effects of treatment and location of HA expression as a biomarker signature remain unknown; this study sought to compare HA expression in primary and metastatic sites of PDAC.

METHODS

Tissue from primary and metastatic PDACs were obtained from Cedars-Sinai Medical Center along with associated clinical data. Tissue slides were stained for H&E, HA, and CD44. Associations between HA levels and the evaluated variables were examined including progression free survival and overall survival.

RESULTS

HA score was significantly higher in primary PDACs compared to sites of metastases (p = 0.0148). Within the metastases, HA score was significantly higher in liver metastases compared to metastases at other sites (p = 0.0478). In the treatment-naive liver metastasis cohort, patients with HA high status had decreased progression free survival and overall survival compared to patients with HA low status (p = 0.0032 and p = 0.0478, respectively).

CONCLUSIONS

HA score is variable between primary PDAC, PDAC metastatic to the liver, and PDAC metastatic to other sites. Within liver metastases, patients with HA high status had decreased progression free survival and overall survival compared to patients with HA low status. HA levels can serve as a potential biomarker to guide pancreatic cancer treatments and trial design for agents targeting the stroma.

Morphological Heterogeneity in Pancreatic Cancer Reflects Structural and Functional Divergence

Simple Summary

Pancreatic cancer has a poor prognosis, which is largely due to resistance to treatment. Tumor heterogeneity is a known cause for treatment failure and has been studied at the molecular level. Morphological heterogeneity is common but has not been investigated, despite the fact that pathology examination is an integral part of clinical diagnostics. This study assessed whether morphological heterogeneity reflects structural and functional diversity in key cancer biological processes. Using archival tissues from resected pancreatic cancer, we selected four common and distinct morphological phenotypes and demonstrated that these differed significantly for a panel of 26 structural and functional features of the cancer-cell and stromal compartments. The strong link between these features and morphological phenotypes allowed prediction of the latter based on the results for the panel of features. The findings of this study indicate that morphological heterogeneity reflects biological diversity and that its assessment may potentially provide clinically relevant information.

Abstract

Inter- and intratumor heterogeneity is an important cause of treatment failure. In human pancreatic cancer (PC), heterogeneity has been investigated almost exclusively at the genomic and transcriptional level. Morphological heterogeneity, though prominent and potentially easily assessable in clinical practice, remains unexplored. This proof-of-concept study aims at demonstrating that morphological heterogeneity reflects structural and functional divergence. From the wide morphological spectrum of conventional PC, four common and distinctive patterns were investigated in 233 foci from 39 surgical specimens. Twenty-six features involved in key biological processes in PC were analyzed (immuno-)histochemically and morphometrically: cancer cell proliferation (Ki67) and migration (collagen fiber alignment, MMP14), cancer stem cells (CD44, CD133, ALDH1), amount, composition and spatial arrangement of extracellular matrix (epithelial proximity, total collagen, collagen I and III, fibronectin, hyaluronan), cancer-associated fibroblasts (density, αSMA), and cancer-stroma interactions (integrins α2, α5, α1; caveolin-1). All features differed significantly between at least two of the patterns. Stromal and cancer-cell-related features co-varied with morphology and allowed prediction of the morphological pattern. In conclusion, morphological heterogeneity in the cancer-cell and stromal compartments of PC correlates with structural and functional diversity. As such, histopathology has the potential to inform on the operationality of key biological processes in individual tumors.

Cellular hyaluronan is associated with a poor prognosis in renal cell carcinoma

PURPOSE

Hyaluronan, a major glycosaminoglycan of the extracellular matrix, can act as an oncogenic component of the tumor microenvironment in many human malignancies. We characterized the hyaluronan content of renal cell carcinomas (RCCs) and investigated its correlations with clinicopathological parameters and patient survival.

PATIENTS AND METHODS

This retrospective study included data from 316 patients that had undergone surgery for RCC in Kuopio University Hospital in 2000 to 2013. The hyaluronan content of surgical tumor samples were histochemically stained with a biotinylated hyaluronan-specific affinity probe. The amount of tumor infiltrating lymphocytes was evaluated in each tumor. Kaplan-Meier and univariate and multivariate Cox-regression analyses were performed to estimate the impact of hyaluronan content on overall survival, disease-specific survival, and metastasis-free survival.

RESULTS

Detectable cellular hyaluronan was associated with higher tumor grades and the presence of tumor infiltrating lymphocytes. Cellular hyaluronan identified a prognostically unfavourable subgroup among low-grade carcinomas. Multivariate analyses showed that measurable cellular hyaluronan was an independent negative prognostic factor for overall survival (hazard ratio [HR] 1.4; 95% confidence interval [CI]: 1.02-2.0; P = 0.039), Disease-specific survival (HR 2.07; 95% CI: 1.2-3.3; P = 0.002), and metastasis-free survival (HR 2.45; 95% CI: 1.37-4.4; P = 0.003).

CONCLUSIONS

Cellular hyaluronan was significantly associated with unfavourable features and a poor prognosis in RCC. Further studies are needed to investigate the biological mechanism underlying hyaluronan accumulation in RCC.