Fibrous stroma is associated with poorer prognosis in lung squamous cell carcinoma patients. J Thorac Oncol. 2011;6:1460-1467. [PMID: 21849853 DOI: 10.1097/jto.0b013e318229189d]

New insights into cancer pathology learned from the dynamics of cancer-associated fibroblasts

Paget's "Seed and Soil" theory, proposed in 1889, emphasizes the importance of the microenvironment where cancer cells grow in metastatic sites. Over a century later, this concept remains a cornerstone in comprehending cancer biology and devising treatment strategies. The "Seed and Soil" theory, which initially explained how cancer spreads to distant organs, now also applies to the tumor microenvironment (TME) within primary tumors. This theory emphasizes the critical interaction between cancer cells ("seeds") and their surrounding environment ("soil") and how this interaction affects both tumor progression within the primary site and at metastatic sites. An important point to note is that the characteristics of the TME are not static but dynamic, undergoing substantial changes during tumor progression and after treatment with therapeutic drugs. Cancer-associated fibroblasts (CAFs), recognized as the principal noncancerous cellular component within the TME, play multifaceted roles in tumor progression including promoting angiogenesis, remodeling the extracellular matrix, and regulating immune responses. In this comprehensive review, we focus on the findings regarding how the dynamics of CAFs contribute to cancer progression and drug sensitivity. Understanding the dynamics of CAFs could provide new insights into cancer pathology and lead to important advancements in cancer research and treatment.

Effect of smoking on the diagnostic results and complication rates of percutaneous transthoracic needle biopsy

OBJECTIVE

To investigate the association of smoking with the outcomes of percutaneous transthoracic needle biopsy (PTNB).

METHODS

In total, 4668 PTNBs for pulmonary lesions were retrospectively identified. The associations of smoking status (never, former, current smokers) and smoking intensity (≤ 20, 21-40, > 40 pack-years) with diagnostic results (malignancy, non-diagnostic pathologies, and false-negative results in non-diagnostic pathologies) and complications (pneumothorax and hemoptysis) were assessed using multivariable logistic regression analysis.

RESULTS

Among the 4668 PTNBs (median age of the patients, 66 years [interquartile range, 58-74]; 2715 men), malignancies, non-diagnostic pathologies, and specific benign pathologies were identified in 3054 (65.4%), 1282 (27.5%), and 332 PTNBs (7.1%), respectively. False-negative results for malignancy occurred in 20.5% (236/1153) of non-diagnostic pathologies with decidable reference standards. Current smoking was associated with malignancy (adjusted odds ratio [OR], 1.31; 95% confidence interval [CI]: 1.02-1.69; p = 0.03) and false-negative results (OR, 2.64; 95% CI: 1.32-5.28; p = 0.006), while heavy smoking (> 40 pack-years) was associated with non-diagnostic pathologies (OR, 1.69; 95% CI: 1.19-2.40; p = 0.003) and false-negative results (OR, 2.12; 95% CI: 1.17-3.92; p = 0.02). Pneumothorax and hemoptysis occurred in 21.8% (1018/4668) and 10.6% (495/4668) of PTNBs, respectively. Heavy smoking was associated with pneumothorax (OR, 1.33; 95% CI: 1.01-1.74; p = 0.04), while heavy smoking (OR, 0.64; 95% CI: 0.40-0.99; p = 0.048) and current smoking (OR, 0.64; 95% CI: 0.42-0.96; p = 0.04) were inversely associated with hemoptysis.

CONCLUSION

Smoking history was associated with the outcomes of PTNBs. Current and heavy smoking increased false-negative results and changed the complication rates of PTNBs.

CLINICAL RELEVANCE STATEMENT

Smoking status and intensity were independently associated with the outcomes of PTNBs. Non-diagnostic pathologies should be interpreted cautiously in current or heavy smokers. A patient's smoking history should be ascertained before PTNB to predict and manage complications.

KEY POINTS

• Smoking status and intensity might independently contribute to the diagnostic results and complications of PTNBs. • Current and heavy smoking (> 40 pack-years) were independently associated with the outcomes of PTNBs. • Operators need to recognize the association between smoking history and the outcomes of PTNBs.

Population-based high-dimensional analyses identify multiple intrinsic characters for cancer vaccines against lung squamous cell carcinoma

In lung squamous cell carcinoma (LUSC), current cancer vaccines show promising effects, despite a lack of benefit for a large number of patients. We first identified the tumor antigens into shared and private antigens, and determined the population by clustering analysis in public datasets. For vaccine development, The Cancer Genome Atlas (TCGA) and Clinical Proteomic Tumor Analysis Consortium (CPTAC) were collected. WGCNA method was furthermore applied to construct a consensus gene co-expression network based on TCGA and CPTAC datasets. The main analyses in bulk sequencing included survival, clinical features, tumor microenvironment (TME), and pathways enrichment. In addition, single-cell RNA (scRNA) analysis of cancer epithelium dissected consensus subtype. We identified the ideal population for cancer vaccines, and candidate neoantigens including AOC1, COL5A2, LGI2, and POSTN. According to subtype analysis, Lung squamous 1 (LSQ1) type exhibited a higher tumor mutational load (TMB) and copy number but no immune infiltration, whereas lung squamous 2 (LSQ2) tumors had a higher global methylation level and more fibroblasts but had less stemness. Meanwhile, trajectory analysis further revealed that the evolution of TME influenced prognosis. We emphasized specific pathways or targets with the potential for combination immunotherapy by consensus network and single-cell RNA analyses. Anti-androgen therapy has been validated in vitro experiments of LUSC as proof of concept. In conclusion, LSQ1 was linked to immune exclusion and might be utilized for vaccination, while LSQ2 was linked to immune dysfunction and could be used for programmed cell death protein 1 (PD1) blocking therapy.

Tumor-associated fibrosis impairs immune surveillance and response to immune checkpoint blockade in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related deaths. Immune checkpoint blockade has improved survival for many patients with NSCLC, but most fail to obtain long-term benefit. Understanding the factors leading to reduced immune surveillance in NSCLC is critical in improving patient outcomes. Here, we show that human NSCLC harbors large amounts of fibrosis that correlates with reduced T cell infiltration. In murine NSCLC models, the induction of fibrosis led to increased lung cancer progression, impaired T cell immune surveillance, and failure of immune checkpoint blockade efficacy. Associated with these changes, we observed that fibrosis leads to numerically and functionally impaired dendritic cells and altered macrophage phenotypes that likely contribute to immunosuppression. Within cancer-associated fibroblasts, distinct changes within the Col13a1-expressing population suggest that these cells produce chemokines to recruit macrophages and regulatory T cells while limiting recruitment of dendritic cells and T cells. Targeting fibrosis through transforming growth factor-β receptor signaling overcame the effects of fibrosis to enhance T cell responses and improved the efficacy of immune checkpoint blockade but only in the context of chemotherapy. Together, these data suggest that fibrosis in NSCLC leads to reduced immune surveillance and poor responsiveness to checkpoint blockade and highlight antifibrotic therapies as a candidate strategy to overcome immunotherapeutic resistance.

Integrin α11β1 in tumor fibrosis: more than just another cancer-associated fibroblast biomarker?

There is currently an increased interest in understanding the role of the tumor microenvironment (TME) in tumor growth and progression. In this context the role of integrins in cancer-associated fibroblasts (CAFs) will need to be carefully re-evaluated. Fibroblast-derived cells are not only in the focus in tumors, but also in tissue fibrosis as well as in inflammatory conditions. The recent transcriptional profiling of what has been called "the pan-fibroblast cell lineage" in mouse and human tissues has identified novel transcriptional biomarker mRNAs encoding the secreted ECM proteins dermatopontin and collagen XV as well as the phosphatidylinositol-anchored membrane protein Pi16. Some of the genes identified in these fibroblasts scRNA-seq datasets will be useful for rigorous comparative characterizations of fibroblast-derived cell subpopulations. At the same time, it will be a challenge in the coming years to validate these transcriptional mRNA datasets at the protein-(expression) and at tissue-(distribution) levels and to find useful protein biomarker reagents that will facilitate fibroblast profiling at the cell level. In the current review we will focus on the role of the collagen-binding integrin α11β1 in CAFs, summarizing our own work as well as published datasets with information on α11 mRNA expression in selected tumors. Our experimental data suggest that α11β1 is more than just another biomarker and that it as a functional collagen receptor in the TME is playing a central role in regulating collagen assembly and matrix remodeling, which in turn impact tumor growth and metastasis.

Extracellular matrix profiles determine risk and prognosis of the squamous cell carcinoma subtype of non-small cell lung carcinoma

BACKGROUND

Squamous cell carcinoma (SqCC) is a subtype of non-small cell lung cancer for which patient prognosis remains poor. The extracellular matrix (ECM) is critical in regulating cell behavior; however, its importance in tumor aggressiveness remains to be comprehensively characterized.

METHODS

Multi-omics data of SqCC human tumor specimens was combined to characterize ECM features associated with initiation and recurrence. Penalized logistic regression was used to define a matrix risk signature for SqCC tumors and its performance across a panel of tumor types and in SqCC premalignant lesions was evaluated. Consensus clustering was used to define prognostic matreotypes for SqCC tumors. Matreotype-specific tumor biology was defined by integration of bulk RNAseq with scRNAseq data, cell type deconvolution, analysis of ligand-receptor interactions and enriched biological pathways, and through cross comparison of matreotype expression profiles with aging and idiopathic pulmonary fibrosis lung profiles.

RESULTS

This analysis revealed subtype-specific ECM signatures associated with tumor initiation that were predictive of premalignant progression. We identified an ECM-enriched tumor subtype associated with the poorest prognosis. In silico analysis indicates that matrix remodeling programs differentially activate intracellular signaling in tumor and stromal cells to reinforce matrix remodeling associated with resistance and progression. The matrix subtype with the poorest prognosis resembles ECM remodeling in idiopathic pulmonary fibrosis and may represent a field of cancerization associated with elevated cancer risk.

CONCLUSIONS

Collectively, this analysis defines matrix-driven features of poor prognosis to inform precision medicine prevention and treatment strategies towards improving SqCC patient outcome.

Targeting of the Peritumoral Adipose Tissue Microenvironment as an Innovative Antitumor Therapeutic Strategy

The tumor microenvironment (TME) plays a key role in promoting and sustaining cancer growth. Adipose tissue (AT), due to its anatomical distribution, is a prevalent component of TME, and contributes to cancer development and progression. Cancer-associated adipocytes (CAAs), reprogrammed by cancer stem cells (CSCs), drive cancer progression by releasing metabolites and inflammatory adipokines. In this review, we highlight the mechanisms underlying the bidirectional crosstalk among CAAs, CSCs, and stromal cells. Moreover, we focus on the recent advances in the therapeutic targeting of adipocyte-released factors as an innovative strategy to counteract cancer progression.

Extracellular Matrices and Cancer-Associated Fibroblasts: Targets for Cancer Diagnosis and Therapy?

Solid cancer progression is dictated by neoplastic cell features and pro-tumoral crosstalks with their microenvironment. Stroma modifications, such as fibroblast activation into cancer-associated fibroblasts (CAFs) and extracellular matrix (ECM) remodeling, are now recognized as critical events for cancer progression and as potential therapeutic or diagnostic targets. The recent appreciation of the key, complex and multiple roles of the ECM in cancer and of the CAF diversity, has revolutionized the field and raised innovative but challenging questions. Here, we rapidly present CAF heterogeneity in link with their specific ECM remodeling features observed in cancer, before developing each of the impacts of such ECM modifications on tumor progression (survival, angiogenesis, pre-metastatic niche, chemoresistance, etc.), and on patient prognosis. Finally, based on preclinical studies and recent results obtained from clinical trials, we highlight key mechanisms or proteins that are, or may be, used as potential therapeutic or diagnostic targets, and we report and discuss benefits, disappointments, or even failures, of recently reported stroma-targeting strategies.

Long Distance From Microvessel to Cancer Cell Predicts Poor Prognosis in Non-Small Cell Lung Cancer Patients

Background

Blood supply, which is crucial for nutrition and drug delivery, was determined by microvessel density as well as the diffusion distance between vessels and cancer cells. Therefore, we evaluated the distance from microvessels to cancer cells (D_mvcc) and its role in the prognosis of non-small cell lung cancer (NSCLC) patients.

Methods

Patients with primary NSCLC were retrospectively analyzed. The tumor samples were immunochemically stained with CD31 to visualize the microvessels. The D_mvcc was defined as the mean distance from each microvessel to its nearest cancer cell in the "hot-spot" of an individual patient. The patients were stratified into short- and long-distance groups using five strategies, including dichotomy by the median value, optimal cutoff, trichotomy, quartation and per-10 µm increase. The correlation between the D_mvcc and survival was evaluated by using univariate and multivariate analyses with various D_mvcc strategies.

Results

In total, 100 patients were analyzed. The median value of D_mvcc was 13.1 μm (ranged, 1.6 to 269.7 μm; mean value, 24.4 ± 33.5 μm). The optimal cutoff value of D_mvcc for predicting survival outcome was 20 μm. D_mvcc was significantly related to overall survival (OS) with all the five categories (p = 0.001-0.000004) and progression-free survival (PFS) categorized by optimal cutoff value (p = 0.024), trichotomy (p = 0.041) and per-10 µm increase (p = 0.040) after adjusting for other factors. Patients with longer D_mvcc (≥20 μm) were observed to have poor survival outcomes (OS: HR = 13.5, 95CI: 4.42-41.18, p = 0.000005; PFS: 3.26, 95CI: 1.56-6.81, p = 0.002). A high D_mvcc per-10 µm was associated with a significantly increased risk of cancer-related death and progression by 98% (p = 0.0001) and 30% (p = 0.044), respectively.

Conclusion

The NSCLC tissues had varying distances from microvessels to cancer cells, and long distances were strongly associated with poor survival.

The prognostic impact of the tumour stroma fraction: A machine learning-based analysis in 16 human solid tumour types

Background

The development of a reactive tumour stroma is a hallmark of tumour progression and pronounced tumour stroma is generally considered to be associated with clinical aggressiveness. The variability between tumour types regarding stroma fraction, and its prognosis associations, have not been systematically analysed.

Methods

Using an objective machine-learning method we quantified the tumour stroma in 16 solid cancer types from 2732 patients, representing retrospective tissue collections of surgically resected primary tumours. Image analysis performed tissue segmentation into stromal and epithelial compartment based on pan-cytokeratin staining and autofluorescence patterns.

Findings

The stroma fraction was highly variable within and across the tumour types, with kidney cancer showing the lowest and pancreato-biliary type periampullary cancer showing the highest stroma proportion (median 19% and 73% respectively). Adjusted Cox regression models revealed both positive (pancreato-biliary type periampullary cancer and oestrogen negative breast cancer, HR(95%CI)=0.56(0.34-0.92) and HR(95%CI)=0.41(0.17-0.98) respectively) and negative (intestinal type periampullary cancer, HR(95%CI)=3.59(1.49-8.62)) associations of the tumour stroma fraction with survival.

Interpretation

Our study provides an objective quantification of the tumour stroma fraction across major types of solid cancer. Findings strongly argue against the commonly promoted view of a general associations between high stroma abundance and poor prognosis. The results also suggest that full exploitation of the prognostic potential of tumour stroma requires analyses that go beyond determination of stroma abundance.

Funding

The Swedish Cancer Society, The Lions Cancer Foundation Uppsala, The Swedish Government Grant for Clinical Research, The Mrs Berta Kamprad Foundation, Sweden, Sellanders foundation, P.O.Zetterling Foundation, and The Sjöberg Foundation, Sweden.

Fibrous bands associated with higher Masaoka stage and poor recurrence-free survival in patients with thymoma

Background

Fibrous bands (FBs) are one of the histological features in tumors which can be confirmed by hematoxylin and eosin (H&E)‐stained slides. FBs have been reported to correlate with malignancy in various tumors. This study aimed to investigate whether the presence of FBs is associated with malignancy in thymoma.

Methods

A total of 123 consecutive patients with thymoma who underwent microscopically complete resections from January 2000 to December 2018 were enrolled into this study. H&E‐stained slides of all thymoma patients were re‐examined. Study patients were classified into two groups: with FBs (n = 36) and without FBs (n = 87). Clinicopathological characteristics, overall survival (OS), and recurrence‐free survival (RFS) were compared between the two groups. Furthermore, multivariate analyses were performed to identify whether the presence of FBs was associated with higher Masaoka stage and poor prognosis in patients with thymoma.

Results

The Masaoka stage was found to be higher and recurrence more likely in thymoma patients with FBs than in those without. RFS was significantly poorer in thymoma patients with FBs than in those without, although no significant difference was observed in OS between them. The presence of FBs was significantly associated with higher Masaoka stage in the multivariate analysis using logistic regression. Additionally, the presence of FBs was an independent prognostic factor for poor RFS in multivariate analysis using Cox's proportional hazards model.

Conclusions

The presence of FBs in patients with thymoma was associated with higher Masaoka stage, higher recurrence rate, and poorer RFS.

Key points

Significant findings of the study

Fibrous bands (FBs) are bands of fibrosis dividing tumors into different‐sized irregular islands. The presence of FBs is associated with higher Masaoka stage and poor recurrence‐free survival in patients with thymoma.

What this study adds

The presence of fibrous bands might be associated with the malignant behavior of thymoma. Confirming the presence or absence of FBs may result in personalized medication for patients with thymoma.

Machine learning-based histological classification that predicts recurrence of peripheral lung squamous cell carcinoma

BACKGROUND

Cancer tissue is composed of both a cancer cell component and a stromal component. The aim of this study was to investigate if the component ratio predicts a prognosis for lung squamous cell carcinoma (SqCC) patients by using a machine learning method.

METHODS

A total of 135 peripheral SqCC cases (tumor size: 3-5 cm) were enrolled in this study. The areas of the cancer cell component, the necrotic component, and the stromal component were accurately measured via a machine learning method. Each case was divided into the following three subtypes: 1) predominant cancer cell, 2) predominant necrosis, and 3) predominant stroma. The study examined if a particular subtype had prognostic significance.

RESULTS

The number of cases per subtype of predominant cancer cell, predominant necrosis, and predominant stroma was 59, 6, and 70, respectively. Patients with the predominant stroma subtype had a significantly shorter recurrence free survival (RFS) than did those with the predominant cancer cell subtype (5-yr RFS: 42.3 % vs. 84.3 %,p < 0.01). Also, in pathological stage I patients, the 5-year RFS rate for the predominant stroma subtype was significantly shorter (5-yr RFS: 64.3 % vs. 88.4 %, p < 0.01). In the multivariate analysis of p-stage I patients, the predominant stroma subtype was confirmed to be an independent prognostic factor for RFS (p < 0.01).

CONCLUSION

Using machine learning, the study confirmed that the predominant stroma subtype was an independent factor for RFS, suggesting that the ratio of the stromal component correlates with the malignant potential of SqCC.

IASLC Multidisciplinary Recommendations for Pathologic Assessment of Lung Cancer Resection Specimens After Neoadjuvant Therapy

Currently, there is no established guidance on how to process and evaluate resected lung cancer specimens after neoadjuvant therapy in the setting of clinical trials and clinical practice. There is also a lack of precise definitions on the degree of pathologic response, including major pathologic response or complete pathologic response. For other cancers such as osteosarcoma and colorectal, breast, and esophageal carcinomas, there have been multiple studies investigating pathologic assessment of the effects of neoadjuvant therapy, including some detailed recommendations on how to handle these specimens. A comprehensive mapping approach to gross and histologic processing of osteosarcomas after induction therapy has been used for over 40 years. The purpose of this article is to outline detailed recommendations on how to process lung cancer resection specimens and to define pathologic response, including major pathologic response or complete pathologic response after neoadjuvant therapy. A standardized approach is recommended to assess the percentages of (1) viable tumor, (2) necrosis, and (3) stroma (including inflammation and fibrosis) with a total adding up to 100%. This is recommended for all systemic therapies, including chemotherapy, chemoradiation, molecular-targeted therapy, immunotherapy, or any future novel therapies yet to be discovered, whether administered alone or in combination. Specific issues may differ for certain therapies such as immunotherapy, but the grossing process should be similar, and the histologic evaluation should contain these basic elements. Standard pathologic response assessment should allow for comparisons between different therapies and correlations with disease-free survival and overall survival in ongoing and future trials. The International Association for the Study of Lung Cancer has an effort to collect such data from existing and future clinical trials. These recommendations are intended as guidance for clinical trials, although it is hoped they can be viewed as suggestion for good clinical practice outside of clinical trials, to improve consistency of pathologic assessment of treatment response.

Force-dependent extracellular matrix remodeling by early-stage cancer cells alters diffusion and induces carcinoma-associated fibroblasts

It is known cancer cells secrete cytokines inducing normal fibroblasts (NFs) to become carcinoma-associated fibroblasts (CAFs). However, it is not clear how the CAF-promoting cytokines can effectively navigate the dense ECM, a diffusion barrier, in the tumor microenvironment to reach NFs during the early stages of cancer development. In this study, we devised a 3D coculture system to investigate the possible mechanism of CAF induction at early stages of breast cancer. We found that in a force-dependent manner, ECM fibrils are radially aligned relative to the tumor spheroid. The fibril alignment enhances the diffusion of exosomes containing CAF-promoting cytokines towards NFs. Suppression of force generation or ECM remodeling abolishes the enhancement of exosome diffusion and the subsequent CAF induction. In summary, our finding suggests that early-stage, pre-metastatic cancer cells can generate high forces to align the ECM fibrils, thereby enhancing the diffusion of CAF-promoting exosomes to reach the stroma and induce CAFs.

Lung Cancer Staging

Lung cancer staging is a foundation of patient care, informing management decisions and prognosis. This comprehensive overview of the current 8th edition American Joint Committee on Cancer Cancer Staging Manual addresses common difficulties in staging, such as measuring the invasive component of adenocarcinomas and staging multiple lung nodules.

Stromal markers of activated tumor associated fibroblasts predict poor survival and are associated with necrosis in non-small cell lung cancer

OBJECTIVES

Tumor associated fibroblasts (TAFs) are essential contributors of the progression of non-small cell lung cancer (NSCLC). Most lung TAFs exhibit an activated phenotype characterized by the expression of α-SMA and fibrillar collagens. However, the prognostic value of these activation markers in NSCLC remains unclear.

MATERIAL AND METHODS

We conducted a quantitative image analysis of α-SMA immunostaining and picrosirius red staining of fibrillar collagens imaged by bright-field and polarized microscopy, respectively, using tissue microarrays with samples from 220 surgical patients, which elicited a percentage of positive staining area for each marker and patient.

RESULTS

Kaplan-Meier curves showed that all TAF activation markers were significantly associated with poor survival, and their prognostic value was independent of TNM staging as revealed by multivariate analysis, which elicited an adjusted increased risk of death after 3 years of 129% and 94% for fibrillar collagens imaged with bright-field (p = 0.004) and polarized light (p = 0.003), respectively, and of 89% for α-SMA (p = 0.009). We also found a significant association between all TAF activation markers and tumor necrosis, which is often indicative of hypoxia, supporting a pathologic link between tumor desmoplasia and necrosis/hypoxia.

CONCLUSIONS

Our findings identify patients with large histologic coverage of fibrillar collagens and α-SMA + TAFs to be at higher risk of recurrence and death, supporting that they could be considered for adjuvant therapy.

Characterization of Distinct Populations of Carcinoma-Associated Fibroblasts from Non-Small Cell Lung Carcinoma Reveals a Role for ST8SIA2 in Cancer Cell Invasion

Carcinoma-associated fibroblasts (CAFs) are abundant stromal cells in tumor microenvironment that are critically involved in cancer progression. Contrasting reports have shown that CAFs can have either pro- or antitumorigenic roles, indicating that CAFs are functionally heterogeneous. Therefore, to precisely target the cancer-promoting CAF subsets, it is necessary to identify specific markers to define these subpopulations and understand their functions. We characterized two CAFs subsets from 28 non–small cell lung cancer (NSCLC) patient tumors that were scored and classified based on desmoplasia [mainly characterized by proliferating CAFs; high desmoplastic CAFs (HD-CAF; n = 15) and low desmoplastic CAFs (LD-CAF; n = 13)], which is an independent prognostic factor. Here, for the first time, we demonstrate that HD-CAFs and LD-CAFs show different tumor-promoting abilities. HD-CAFs showed higher rate of collagen matrix remodeling, invasion, and tumor growth compared to LD-CAFs. Transcriptomic analysis identified 13 genes that were differentially significant (fold ≥1.5; adjusted P value < .1) between HD-CAFs and LD-CAFs. The top upregulated differentially expressed gene, ST8SIA2 (11.3 fold; adjusted P value = .02), enhanced NSCLC tumor cell invasion in 3D culture compared to control when it was overexpressed in CAFs, suggesting an important role of ST8SIA2 in cancer cell invasion. We confirmed the protumorigenic role of ST8SIA2, showing that ST8SIA2 was significantly associated with the risk of relapse in three independent NSCLC clinical datasets. In summary, our studies show that functional heterogeneity in CAF plays key role in promoting cancer cell invasion in NSCLC.

ΔNp63 in squamous cell carcinoma: defining the oncogenic routes affecting epigenetic landscape and tumour microenvironment

Squamous cell carcinoma (SCC) is a treatment‐refractory tumour which arises from the epithelium of diverse anatomical sites such as oesophagus, head and neck, lung and skin. Accumulating evidence has revealed a number of genomic, clinical and molecular features commonly observed in SCC of distinct origins. Some of these genetic events culminate in fostering the activity of ΔNp63, a potent oncogene which exerts its pro‐tumourigenic effects by regulating specific transcriptional programmes to sustain malignant cell proliferation and survival. In this review, we will describe the genetic and epigenetic determinants underlying ΔNp63 oncogenic activities in SCC, and discuss some relevant transcriptional effectors of ΔNp63, emphasizing their impact in modulating the crosstalk between tumour cells and tumour microenvironment (TME).

Intratumoral heterogeneity as measured using the tumor-stroma ratio and PET texture analyses in females with lung adenocarcinomas differs from that of males with lung adenocarcinomas or squamous cell carcinomas

We compared intratumoral stromal proportions and positron emission tomography (PET) textural features between females and males with lung adenocarcinoma (ADC) or squamous cell carcinoma (SCC).We retrospectively evaluated 167 consecutive patients (male 122, female 45) who underwent pretreatment fluorodeoxyglucose PET/CT and surgical resection. The tumor-stroma ratios (TSRs) of primary tumors were estimated on hematoxylin-and-eosin-stained histological sections, and higher-order textural features were extracted on PET. We compared the histological and PET features between the sexes.More females than males had ADC. Age and pathological tumor size did not significantly differ between females and males. Females with ADC had more stroma-rich tumors than males with ADC (P = .016) or SCC (P = .047). In addition, some PET textural features significantly differed between females with ADC and males with ADC and SCC; short run emphasis, long run emphasis, coarseness, strength, short-zone emphasis, zone percentage and high-intensity large-zone percentage were the commonly differed textural features. However, the TSRs and PET textural features did not significantly differ between males with ADC or SCC.Intratumoral heterogeneity in females with lung ADC differs from that in males with lung ADC or SCC.

Membrane-bound ICAM-1 contributes to the onset of proinvasive tumor stroma by controlling acto-myosin contractility in carcinoma-associated fibroblasts

Acto-myosin contractility in carcinoma-associated fibroblasts leads to assembly of the tumor extracellular matrix. The pro-inflammatory cytokine LIF governs fibroblast activation in cancer by regulating the myosin light chain 2 activity. So far, however, how LIF mediates cytoskeleton contractility remains unknown. Using phenotypic screening assays based on knock-down of LIF-dependent genes in fibroblasts, we identified the glycoprotein ICAM-1 as a crucial regulator of stroma fibroblast proinvasive matrix remodeling. We demonstrate that the membrane-bound ICAM-1 isoform is necessary and sufficient to promote inflammation-dependent extracellular matrix contraction, which favors cancer cell invasion. Indeed, ICAM-1 mediates generation of acto-myosin contractility downstream of the Src kinases in stromal fibroblasts. Moreover, acto-myosin contractility regulates ICAM-1 expression by establishing a positive feedback signaling. Thus, targeting stromal ICAM-1 might constitute a possible therapeutic mean to counteract tumor cell invasion and dissemination.

Quantitative Proteomic Analysis of Optimal Cutting Temperature (OCT) Embedded Core-Needle Biopsy of Lung Cancer

With recent advances in understanding the genomic underpinnings and oncogenic drivers of pathogenesis in different subtypes, it is increasingly clear that proper pretreatment diagnostics are essential for the choice of appropriate treatment options for non-small cell lung cancer (NSCLC). Tumor tissue preservation in optimal cutting temperature (OCT) compound is commonly used in the surgical suite. However, proteins recovered from OCT-embedded specimens pose a challenge for LC-MS/MS experiments, due to the large amounts of polymers present in OCT. Here we present a simple workflow for whole proteome analysis of OCT-embedded NSCLC tissue samples, which involves a simple trichloroacetic acid precipitation step. Comparisons of protein recovery between frozen versus OCT-embedded tissue showed excellent consistency with more than 9200 proteins identified. Using an isobaric labeling strategy, we quantified more than 5400 proteins in tumor versus normal OCT-embedded core needle biopsy samples. Gene ontology analysis indicated that a number of proliferative as well as squamous cell carcinoma (SqCC) marker proteins were overexpressed in the tumor, consistent with the patient's pathology based diagnosis of "poorly differentiated SqCC". Among the most downregulated proteins in the tumor sample, we noted a number of proteins with potential immunomodulatory functions. Finally, interrogation of the aberrantly expressed proteins using a candidate approach and cross-referencing with publicly available databases led to the identification of potential druggable targets in DNA replication and DNA damage repair pathways. We conclude that our approach allows LC-MS/MS proteomic analyses on OCT-embedded lung cancer specimens, opening the way to bring powerful proteomics into the clinic. Graphical Abstract ᅟ.

Magnetic resonance based texture parameters as potential imaging biomarkers for predicting long-term survival in locally advanced rectal cancer treated by chemoradiotherapy

AIM

The study aimed to investigate whether textural features of rectal cancer on MRI can predict long-term survival in patients treated with long-course chemoradiotherapy.

METHOD

Textural analysis (TA) using a filtration-histogram technique of T2-weighted pre- and 6-week post-chemoradiotherapy MRI was undertaken using TexRAD, a proprietary software algorithm. Regions of interest enclosing the largest cross-sectional area of the tumour were manually delineated on the axial images and the filtration step extracted features at different anatomical scales (fine, medium and coarse) followed by quantification of statistical features [mean intensity, standard deviation, entropy, skewness, kurtosis and mean of positive pixels (MPP)] using histogram analysis. Cox multiple regression analysis determined which univariate features including textural, radiological and histological independently predicted overall survival (OS), disease-free survival (DFS) and recurrence-free survival (RFS).

RESULTS

MPP [fine texture, hazard ratio (HR) 6.9, 95% CI: 2.43-19.55, P < 0.001], mean (medium texture, HR 5.6, 95% CI: 1.4-21.7, P = 0.007) and extramural venous invasion (EMVI) on MRI (HR 2.96, 95% CI: 1.04-8.37, P = 0.041) independently predicted OS while mean (medium texture, HR 4.53, 95% CI: 1.58-12.94, P = 0.003), MPP (fine texture, HR 3.36, 95% CI: 1.36-8.31, P = 0.008) and threatened circumferential resection margin (CRM) on MRI (HR 3.1, 95% CI: 1.01-9.46, P = 0.046) predicted DFS. For OS, EMVI on MRI (HR 4.23, 95% CI: 1.41-12.69, P = 0.01) and for DFS kurtosis (medium texture, HR 3.97, 95% CI: 1.44-10.94, P = 0.007) and CRM involvement on MRI (HR 3.36, 95% CI: 1.21-9.32, P = 0.02) were the independent post-treatment factors. Only TA independently predicted RFS on pre- or post-treatment analyses.

CONCLUSION

MR based TA of rectal cancers can predict outcome before undergoing surgery and could potentially select patients for individualized therapy.

Morphoproteomic Characterization of Lung Squamous Cell Carcinoma Fragmentation, a Histological Marker of Increased Tumor Invasiveness

Accurate stratification of tumors is imperative for adequate cancer management. In addition to staging, morphologic subtyping allows stratification of patients into additional prognostic groups. In this study, we used an image-based computational method on pan-cytokeratin IHC stainings to quantify tumor fragmentation (TF), a measure of tumor invasiveness of lung squamous cell carcinoma (LSCC). In two independent clinical cohorts from tissue microarrays (TMA: n = 208 patients) and whole sections (WS: n = 99 patients), TF was associated with poor prognosis and increased risk of blood vessel infiltration. A third cohort from The Cancer Genome Atlas (TCGA: n = 335 patients) confirmed the poor prognostic value of TF using a similar human-based score on hematoxylin-eosin staining. Integration of RNA-seq data from TCGA and LC-MS/MS proteomics from WS revealed an upregulation of extracellular matrix remodeling and focal adhesion processes in tumors with high TF, supporting their increased invasive potential. This proposed histologic parameter is an independent and unfavorable prognostic marker that could be established as a new grading parameter for LSCC. Cancer Res; 77(10); 2585-93. ©2017 AACR.

High Intratumoral Stromal Content Defines Reactive Breast Cancer as a Low-risk Breast Cancer Subtype

PURPOSE

The current study evaluated associative effects of breast cancer cells with the tumor microenvironment and its influence on tumor behavior.

EXPERIMENTAL DESIGN

Formalin-fixed, paraffin-embedded tissue and matched protein lysates were evaluated from two independent breast cancer patient datasets (TCGA and MD Anderson). Reverse-phase protein arrays (RPPA) were utilized to create a proteomics signature to define breast tumor subtypes. Expression patterns of cell lines and normal breast tissues were utilized to determine markers that were differentially expressed in stroma and cancer cells. Protein localization and stromal contents were evaluated for matched cases by imaging.

RESULTS

A subtype of breast cancers designated "Reactive," previously identified by RPPA that was not predicted by mRNA profiling, was extensively characterized. These tumors were primarily estrogen receptor (ER)-positive/human EGF receptor (HER)2-negative, low-risk cancers as determined by enrichment of low-grade nuclei, lobular or tubular histopathology, and the luminal A subtype by PAM50. Reactive breast cancers contained high numbers of stromal cells and the highest extracellular matrix content typically without infiltration of immune cells. For ER-positive/HER2-negative cancers, the Reactive classification predicted favorable clinical outcomes in the TCGA cohort (HR, 0.36; P < 0.05).

CONCLUSIONS

A protein stromal signature in breast cancers is associated with a highly differentiated phenotype. The stromal compartment content and proteins are an extended phenotype not predicted by mRNA expression that could be utilized to subclassify ER-positive/HER2-negative breast cancers. Clin Cancer Res; 22(20); 5068-78. ©2016 AACR.

Hematopoietic stem cell-derived cancer-associated fibroblasts are novel contributors to the pro-tumorigenic microenvironment

Targeting the tumor microenvironment is critical toward improving the effectiveness of cancer therapeutics. Cancer-associated fibroblasts (CAFs) are one of the most abundant cell types of the tumor microenvironment, playing an important role in tumor progression. Multiple origins for CAFs have been proposed including resident fibroblasts, adipocytes, and bone marrow. Our laboratory previously identified a novel hematopoietic stem cell (HSC) origin for CAFs; however, the functional roles of HSC-derived CAFs (HSC-CAFs) in tumor progression have not yet been examined. To test the hypothesis that HSC-CAFs promote tumor progression through contribution to extracellular matrix (ECM) and paracrine production of pro-angiogenic factors, we developed a method to isolate HSC-CAFs. HSC-CAFs were profiled on the basis of their expression of hematopoietic and fibroblastic markers in two murine tumor models. Profiling revealed production of factors associated with ECM deposition and remodeling. Functional in vivo studies showed that co-injection of HSC-CAFs with tumor cells resulted in increased tumor growth rate and significantly larger tumors than tumor cells alone. Immunohistochemical studies revealed increased blood vessel density with co-injection, demonstrating a role for HSC-CAFs in tumor vascularization. Mechanistic in vitro studies indicated that HSC-CAFs play a role in producing vascular endothelial growth factor A and transforming growth factor–β1 in endothelial tube formation and patterning. In vitro and in vivo findings suggest that HSC-CAFs are a critical component of the tumor microenvironment and suggest that targeting the novel HSC-CAF may be a promising therapeutic strategy.

Epigenetic switch drives the conversion of fibroblasts into proinvasive cancer-associated fibroblasts

Carcinoma-associated fibroblasts (CAF) mediate the onset of a proinvasive tumour microenvironment. The proinflammatory cytokine LIF reprograms fibroblasts into a proinvasive phenotype, which promotes extracellular matrix remodelling and collective invasion of cancer cells. Here we unveil that exposure to LIF initiates an epigenetic switch leading to the constitutive activation of JAK1/STAT3 signalling, which results in sustained proinvasive activity of CAF. Mechanistically, p300-histone acetyltransferase acetylates STAT3, which, in turn, upregulates and activates the DNMT3b DNA methyltransferase. DNMT3b methylates CpG sites of the SHP-1 phosphatase promoter, which abrogates SHP-1 expression, and results in constitutive phosphorylation of JAK1. Sustained JAK1/STAT3 signalling is maintained by DNA methyltransferase DNMT1. Consistently, in human lung and head and neck carcinomas, STAT3 acetylation and phosphorylation are inversely correlated with SHP-1 expression. Combined inhibition of DNMT activities and JAK signalling, in vitro and in vivo, results in long-term reversion of CAF-associated proinvasive activity and restoration of the wild-type fibroblast phenotype.

Carcinoma-associated fibroblasts are key components of solid tumours and associated with poor clinical outcome. Here the authors show that the cytokine LIF initiates an epigenetic switch which results in the sustained invasive activity of the tumour cells.

The prognostic value of morphologic findings for lung squamous cell carcinoma patients

BACKGROUND

Novel histopathological prognostic features for squamous cell carcinoma (SCC) of lung, such as tumor budding, mitotic rate, tumor stroma ratio, stroma type, stromal inflammation and necrosis, have been evaluated in the literature. In this study, the prognostic value of multiple morphological features is assessed in lung SCC.

MATERIALS AND METHODS

This study reports on seventy-six patients with lung SCC treated with complete surgical excision. Tumor size, tumor stage, lymph node status, lymphovascular invasion, histopathologic grade, mitotic count, necrosis, tumor budding, tumor stroma ratio, stroma type, stromal lymphoplasmacytic reaction and ratios of stromal plasma cells and their relationship with the prognosis were evaluated. Univariate and multivariate analyses were performed for histopathological markers for local disease free survival (LDFS), distant disease free survival (DDFS), overall disease free survival (ODFS) and overall survival (OS).

RESULTS

The univariate prognostic analysis of the pathological factors revealed that the pathological stage (OS: p=0.001, DDFS: p=0.040), lymph node metastases (OS: p=0.013), mitotic index (OS: p=0.026), tumor necrosis (DDFS: p=0.013, ODFS: p=0.021) and tumor size (OS: p=0.002) had a prognostic significance. The multivariate analysis demonstrated that the pathological stage (OS: p=0.021), tumor size (OS: p=0.044), lymph node status (DDFS: p=0.019, ODFS; p=0.041) and necrosis (ODFS: p=0.048) were independent prognostic factors.

CONCLUSIONS

Although many histopathological factors have recently been proposed as important prognostic markers, we only found significant results for mitotic index and tumor necrosis, as well as the well known parameters such as tumor stage and lymph node status. To the best of our knowledge, this is the first study evaluating such a wide range of morphological prognostic factors in lung SCC.

Invasion Types Are Associated With Poor Prognosis in Lung Squamous Carcinoma Patients

Although the prognostic significance of the histologic patterns in lung adenocarcinoma is being identified, no significant prognostic indicators in lung squamous carcinoma are accepted as a standard universally. The aim of this study was to evaluate the histologic characteristics incorporating the defined invasion types and distinguish the features that can reflect prognosis.We reviewed all slices of 132 patients with lung squamous carcinoma. The cases were classified according to the World Health Organization (WHO) classification and were evaluated for tumor budding, single cell invasion, large cell invasion, cytologic atypia degree, mitotic count, number of buds, tumor nest size, fibrosis, and necrosis.In univariate analysis, overall survival was associated significantly with age (P = 0.023), lymph nodes metastasis (P < 0.001), distant organ metastasis (P < 0.001), pleural invasion (P < 0.001), tumor budding (P = 0.003), single cell invasion (P = 0.001), mitotic count (P < 0.001), and the cytologic atypia degree (P = 0.009). However, the subtypes of 2004 WHO classification showed no association with outcome (P = 0.209). In multivariate analysis, the independent significant prognostic indicators of lung squamous carcinoma were tumor budding (hazard ratio [HR] = 0.466, P = 0.005), single cell invasion (HR = 0.447, P = 0.003), mitotic count (HR = 0.502, P = 0.048) and cytologic atypia degree (HR = 0.479, P = 0.024).Lung squamous carcinomas with the invasion types were associated with a poor prognosis.

Serum LAMC2 enhances the prognostic value of a multi-parametric panel in non-small cell lung cancer

Background:

Non-small cell lung cancer (NSCLC) lacks reliable serological biomarkers for predicting patients' survival and response to treatment. The present study examined the capability of serum LAMC2 and four known tumour markers for disease prognosis and patients' risk stratification.

Methods:

LAMC2, CA 125, CEA, CYFRA 21-1 and SCC levels were retrospectively measured in sera obtained from 127 patients diagnosed with NSCLC by commercial immunoassays. Prognostic performance of the markers was compared with established clinical parameters and multivariate models were constructed to assess the prognostic complementarity of variables.

Results:

LAMC2 showed significant prognostic ability for overall survival (hazards ratio: 1.607, 95% confidence interval: 1.268–2.037, P<0.0001) in the full cohort. LAMC2 and CYFRA 21-1 combination enhanced prognostic models based on common clinical parameters (c-index: 0.81 vs 0.72, P=0.00018), further enabling stratification of patients into clear risk groups. A bootstrap-based cross-validation analysis was supportive of our findings. Combination of LAMC2 and CA 125 showed similar performance.

Conclusions:

Our preliminary study proposes LAMC2 as a novel NSCLC prognostic factor. LAMC2 combined with CA 125 and CYFRA 21-1 could aid in clinical prediction of NSCLC patients' overall survival and inform clinical practice. Larger studies are necessary to unravel LAMC2's full potential as a new NSCLC biomarker.

Comprehensive pathological analyses in lung squamous cell carcinoma: single cell invasion, nuclear diameter, and tumor budding are independent prognostic factors for worse outcomes

INTRODUCTION

For lung squamous cell carcinomas, there are no pathological findings that have been universally accepted as prognostic factors, with the exception of pathological stage. Tumor budding and nuclear grade have been recognized as a poor prognostic factor in other carcinomas. In this study, we investigated whether pathological findings could determine prognosis in lung squamous cell carcinomas.

METHODS

All available tumor slides from patients with surgically resected, solitary lung squamous cell carcinomas (1999-2009) were reviewed (n = 485; stage I/II/III, 281/136/68). Tumors were evaluated for differentiation, subtypes (keratinizing, nonkeratinizing, basaloid pattern, papillary growth, and clear cell feature), tumor nest size (tumor budding and single cell invasion), and nuclear grade (nuclear diameter and mitosis). Overall survival (OS) was estimated using the Kaplan-Meier method (stratified by pathological stage), and group differences were investigated using the stratified log-rank test and the Cox proportional hazards model.

RESULTS

OS was significantly decreased in patients with versus without single cell invasion (p = 0.002 for the entire tumor and p = 0.001 for tumor edge), with large versus small nuclei (p = 0.011), and with high versus low grade tumor budding (p < 0.001 for maximum and p = 0.007 for total). In multivariate analyses, single cell invasion (hazard ratio [HR], 1.47-1.49), nuclear diameter (HR, 1.09-1.33), and tumor budding (HR, 1.04) were independent prognostic factors of OS. However, histologic subtyping including keratinizing, nonkeratinizing, basaloid, and clear cell subtypes did not show prognostic significance.

CONCLUSIONS

Pathological factors can help stratify prognosis in patients with lung squamous cell carcinomas.

Hematopoietic stem cell-derived adipocytes and fibroblasts in the tumor microenvironment

The tumor microenvironment (TME) is complex and constantly evolving. This is due, in part, to the crosstalk between tumor cells and the multiple cell types that comprise the TME, which results in a heterogeneous population of tumor cells and TME cells. This review will focus on two stromal cell types, the cancer-associated adipocyte (CAA) and the cancer-associated fibroblast (CAF). In the clinic, the presence of CAAs and CAFs in the TME translates to poor prognosis in multiple tumor types. CAAs and CAFs have an activated phenotype and produce growth factors, inflammatory factors, cytokines, chemokines, extracellular matrix components, and proteases in an accelerated and aberrant fashion. Through this activated state, CAAs and CAFs remodel the TME, thereby driving all aspects of tumor progression, including tumor growth and survival, chemoresistance, tumor vascularization, tumor invasion, and tumor cell metastasis. Similarities in the tumor-promoting functions of CAAs and CAFs suggest that a multipronged therapeutic approach may be necessary to achieve maximal impact on disease. While CAAs and CAFs are thought to arise from tissues adjacent to the tumor, multiple alternative origins for CAAs and CAFs have recently been identified. Recent studies from our lab and others suggest that the hematopoietic stem cell, through the myeloid lineage, may serve as a progenitor for CAAs and CAFs. We hypothesize that the multiple origins of CAAs and CAFs may contribute to the heterogeneity seen in the TME. Thus, a better understanding of the origin of CAAs and CAFs, how this origin impacts their functions in the TME, and the temporal participation of uniquely originating TME cells may lead to novel or improved anti-tumor therapeutics.

LAMC2 enhances the metastatic potential of lung adenocarcinoma

Lung cancer is the number one cancer killer, and metastasis is the main cause of high mortality in lung cancer patients. However, mechanisms underlying the development of lung cancer metastasis remain unknown. Using genome-wide transcriptional analysis in an experimental metastasis model, we identified laminin γ2 (LAMC2), an epithelial basement membrane protein, to be significantly upregulated in lung adenocarcinoma metastatic cells. Elevated LAMC2 increased traction force, migration, and invasion of lung adenocarcinoma cells accompanied by the induction of epithelial-mesenchymal transition (EMT). LAMC2 knockdown decreased traction force, migration, and invasion accompanied by EMT reduction in vitro, and attenuated metastasis in mice. LAMC2 promoted migration and invasion via EMT that was integrin β1- and ZEB1-dependent. High LAMC2 was significantly correlated with the mesenchymal marker vimentin expression in lung adenocarcinomas, and with higher risk of recurrence or death in patients with lung adenocarcinoma. We suggest that LAMC2 promotes metastasis in lung adenocarcinoma via EMT and may be a potential therapeutic target.

Noninvasive image texture analysis differentiates K-ras mutation from pan-wildtype NSCLC and is prognostic

BACKGROUND

Non-invasive characterization of a tumor's molecular features could enhance treatment management. Quantitative computed tomography (CT) based texture analysis (QTA) has been used to derive tumor heterogeneity information, and the appearance of the tumors has been shown to relate to patient outcome in non-small cell lung cancer (NSCLC) and other cancers. In this study, we examined the potential of tumoral QTA to differentiate K-ras mutant from pan-wildtype tumors and its prognostic potential using baseline pre-treatment non-contrast CT imaging in NSCLC.

METHODS

Tumor DNA from patients with early-stage NSCLC was analyzed on the LungCarta Panel. Cases with a K-ras mutation or pan-wildtype for 26 oncogenes and tumor suppressor genes were selected for QTA. QTA was applied to regions of interest in the primary tumor. Non-parametric Mann Whitney test assessed the ability of the QTA, clinical and patient characteristics to differentiate between K-ras mutation from pan-wildtype. A recursive decision tree was developed to determine whether the differentiation of K-ras mutant from pan-wildtype tumors could be improved by sequential application of QTA parameters. Kaplan-Meier survival analysis assessed the ability of these markers to predict survival.

RESULTS

QTA was applied to 48 cases identified, 27 had a K-ras mutation and 21 cases were pan-wildtype. Positive skewness and lower kurtosis were significantly associated with the presence of a K-ras mutation. A five node decision tree had sensitivity, specificity, and accuracy values (95% CI) of 96.3% (78.1-100), 81.0% (50.5-97.4), and 89.6% (72.9-97.0); respectively. Kurtosis was a significant predictor of OS and DFS, with a lower kurtosis value linked with poorer survival.

CONCLUSIONS

Lower kurtosis and positive skewness are significantly associated with K-ras mutations. A QTA feature such as kurtosis is prognostic for OS and DFS. Non-invasive QTA can differentiate the presence of K-ras mutation from pan-wildtype NSCLC and is associated with patient survival.

Chromosomal instability associated with global DNA hypomethylation is associated with the initiation and progression of esophageal squamous cell carcinoma

BACKGROUND

Global DNA hypomethylation is associated with increased chromosomal instability and plays an important role in tumorigenesis. The methylation status of the long interspersed nuclear element-1 (LINE-1) element is a useful surrogate marker for global DNA methylation. Although LINE-1 hypomethylation is recognized as a poor prognostic marker, the correlation of LINE-1 methylation level with tumor suppressor gene mutation, chromosomal instability, and clinical significance in esophageal squamous cell carcinoma (ESCC) remains unclear.

METHODS

Using resected tumor tissues and the corresponding normal esophageal mucosa from 105 patients with ESCC, bisulfite pyrosequencing analysis was performed to quantify the LINE-1 methylation levels. p53 mutations in exons two to ten were detected by polymerase chain reaction direct sequencing. Chromosomal instability was assessed by single nucleotide polymorphism array comparative genomic hybridization analysis.

RESULTS

The LINE-1 methylation level of ESCC was significantly lower than matched normal mucosa. LINE-1 methylation levels of normal mucosa from the esophagus had a significant inverse correlation with both cigarette smoking and alcohol consumption of the study subjects. LINE-1 hypomethylation of ESCC was significantly associated with lymph node metastasis, lymphovascular invasion, the frequency of p53 mutation and poor survivability. The LINE-1 methylation levels in ESCC had a significant inverse association with the percentage of copy number alterations in the whole genome, mirroring chromosomal instability.

CONCLUSIONS

Our results suggested that whole genome hypomethylation caused by chronic inflammation could initiate carcinogenesis of esophageal squamous cells through chromosomal instability. In addition, chromosomal instability associated with the global hypomethylation might correlate highly with the progression of ESCC.

LIF mediates proinvasive activation of stromal fibroblasts in cancer

Signaling crosstalk between tumor cells and fibroblasts confers proinvasive properties to the tumor microenvironment. Here, we identify leukemia inhibitory factor (LIF) as a tumor promoter that mediates proinvasive activation of stromal fibroblasts independent of alpha-smooth muscle actin (α-SMA) expression. We demonstrate that a pulse of transforming growth factor β (TGF-β) establishes stable proinvasive fibroblast activation by inducing LIF production in both fibroblasts and tumor cells. In fibroblasts, LIF mediates TGF-β-dependent actomyosin contractility and extracellular matrix remodeling, which results in collective carcinoma cell invasion in vitro and in vivo. Accordingly, carcinomas from multiple origins and melanomas display strong LIF upregulation, which correlates with dense collagen fiber organization, cancer cell collective invasion, and poor clinical outcome. Blockade of JAK activity by Ruxolitinib (JAK inhibitor) counteracts fibroblast-dependent carcinoma cell invasion in vitro and in vivo. These findings establish LIF as a proinvasive fibroblast producer independent of α-SMA and may open novel therapeutic perspectives for patients with aggressive primary tumors.

Prognostic relevance of cancer-associated fibroblasts in human cancer

Prognostication is an integral part of cancer diagnostic and helps oncologists to guide treatment decisions and therapy intensity. Accumulating evidence suggest that the stroma compartment also contains independent prognostic information, best exemplified by the impact of immune cells and cells of the vasculature on cancer progression. Similarly, strong experimental evidence exist that stromal fibroblasts, often designated cancer associated fibroblasts (CAFs), are actively involved in tumorigenesis. Thus, it can be anticipated that the molecular repertoire of CAFs is likewise important for the clinical behavior of the tumor. In this review we present recent studies addressing the prognostic impact of CAFs, with the focus on human lung and breast cancer. Several single markers have been suggested, either CAF specific or CAF derived, that in immunohistochemical studies have demonstrated independent association with survival. This includes members of the platelet derived growth factor receptor (PDGFR) family, CAF-markers like podoplanin and fibroblast activation protein (FAP) as well as transcription factors (FoxF1) and secreted factors (matrix metalloproteinases (MMPs), SPARC). However, most studies are based on explorative evaluations on single patient cohorts and require further validation. Using a more comprehensive approach, microarray studies have been employed to create gene expression signatures that detect an activated fibroblast state. These "stroma signatures" have been applied to identify specific CAF features associated with prognosis in several independent data sets of breast and lung cancer patients. Early studies in breast cancer have also demonstrated that fibroblast features influence therapy response. Thus, many strategies have been used to present encouraging proof-of-concept findings that CAFs could be exploited for prognostication. However, these studies also highlight the difficulties to conclusively define an "activated stroma" and to identify the individual factors involved in clinically relevant tumor-stroma interactions.

Prognostic significance of the Wnt pathway in squamous cell laryngeal cancer

OBJECTIVES

We sought to determine the prognostic significance of the Wnt signaling pathway in operable squamous cell carcinoma of the larynx.

MATERIALS AND METHODS

In an annotated cohort of 289 operable laryngeal cancers we evaluated the prognostic impact of E-cadherin, P-cadherin and β-catenin protein expression with immunohistochemistry, as well as the mRNA expression of 7 key effectors of the Wnt pathway including secreted frizzled-related protein 4 (SFRP4), SNAI2 (SLUG) and WNT5A with qPCR (relative quantification [RQ]).

RESULTS

Using median immunoreactive scores as a pre-defined cut-off, patients whose tumors overexpressed both cytoplasmic E-cadherin and β-catenin experienced longer median OS as compared to those whose tumors overexpressed β-catenin only (median OS 124 vs. 72 months, p=0.0301) and patients whose tumors overexpressed both cytoplasmic and membranous E-cadherin experienced longer DFS as compared to those whose tumors overexpressed cytoplasmic E-cadherin only (median 118 vs. 91 months, p=0.0106). Upon hierarchical clustering of SFRP4, SNAI2 and WNT5A RQ values, profiles including co-expression of all 3 genes but also profiles with under-expression of SNAI2 and WNT5A were associated with worse outcome as compared to profiles not related to the Wnt pathway. In multivariate analysis, clustering was an independent predictor for DFS (p=0.0221) and OS (p=0.0077).

CONCLUSION

We identified gene expression profiles and IHC patterns associated with aberrant Wnt signaling conferring aggressive clinical behavior in operable squamous cell carcinoma of the larynx. Prospective validation of these results will determine whether targeting the Wnt pathway merits investigation in this disease.

Multiphoton microscopy: a potential "optical biopsy" tool for real-time evaluation of lung tumors without the need for exogenous contrast agents

CONTEXT

Multiphoton microscopy (MPM) is an emerging, nonlinear, optical-biopsy technique, which can generate subcellular-resolution images from unprocessed and unstained tissue in real time.

OBJECTIVE

To assess the potential of MPM for lung tumor diagnosis.

DESIGN

Fresh sections from tumor and adjacent nonneoplastic lung were imaged with MPM and then compared with corresponding hematoxylin-eosin slides.

RESULTS

Alveoli, bronchi, blood vessels, pleura, smokers' macrophages, and lymphocytes were readily identified with MPM in nonneoplastic tissue. Atypical adenomatous hyperplasia (a preinvasive lesion) was identified in tissue adjacent to the tumor in one case. Of the 25 tumor specimens used for blinded pathologic diagnosis, 23 were diagnosable with MPM. Of these 23 cases, all but one adenocarcinoma (15 of 16; 94%) was correctly diagnosed on MPM, along with their histologic patterns. For squamous cell carcinoma, 4 of 7 specimens (57%) were correctly diagnosed. For the remaining 3 squamous cell carcinoma specimens, the solid pattern was correctly diagnosed in 2 additional cases (29%), but it was not possible to distinguish the squamous cell carcinoma from adenocarcinoma. The other squamous cell carcinoma specimen (1 of 7; 14%) was misdiagnosed as adenocarcinoma because of pseudogland formation. Invasive adenocarcinomas with acinar and solid pattern showed statistically significant increases in collagen. Interobserver agreement for collagen quantification (among 3 observers) was 80%.

CONCLUSIONS

Our pilot study provides a proof of principle that MPM can differentiate neoplastic from nonneoplastic lung tissue and identify tumor subtypes. If confirmed in a future, larger study, we foresee real-time intraoperative applications of MPM, using miniaturized instruments for directing lung biopsies, assessing their adequacy for subsequent histopathologic analysis or banking, and evaluating surgical margins in limited lung resections.

FGFR2 signaling underlies p63 oncogenic function in squamous cell carcinoma

Oncogenic transcription factors drive many human cancers, yet identifying and therapeutically targeting the resulting deregulated pathways has proven difficult. Squamous cell carcinoma (SCC) is a common and lethal human cancer, and relatively little progress has been made in improving outcomes for SCC due to a poor understanding of its underlying molecular pathogenesis. While SCCs typically lack somatic oncogene-activating mutations, they exhibit frequent overexpression of the p53-related transcription factor p63. We developed an in vivo murine tumor model to investigate the function and key transcriptional programs of p63 in SCC. Here, we show that established SCCs are exquisitely dependent on p63, as acute genetic ablation of p63 in advanced, invasive SCC induced rapid and dramatic apoptosis and tumor regression. In vivo genome-wide gene expression analysis identified a tumor-survival program involving p63-regulated FGFR2 signaling that was activated by ligand emanating from abundant tumor-associated stroma. Correspondingly, we demonstrate the therapeutic efficacy of extinguishing this signaling axis in endogenous SCCs using the clinical FGFR2 inhibitor AZD4547. Collectively, these results reveal an unanticipated role for p63-driven paracrine FGFR2 signaling as an addicting pathway in human cancer and suggest a new approach for the treatment of SCC.

Podoplanin-positive cancer-associated fibroblasts could have prognostic value independent of cancer cell phenotype in stage I lung squamous cell carcinoma: usefulness of combining analysis of both cancer cell phenotype and cancer-associated fibroblast phenotype

BACKGROUND

The prognostic significance of the tumor microenvironment, which is created by both cancer cells and cancer-associated fibroblasts (CAFs), has been increasingly recognized. The purpose of this study was to analyze the prognostic markers of stage I squamous cell carcinoma (SqCC), with special reference to the immunophenotypes of both cancer cells and CAFs.

METHODS

A total of 142 patients with stage I SqCC were included in this study. We examined the expressions of E-cadherin, laminin-5, podoplanin, c-MET, carbonic anhydrase IX (CA-IX), CD10, and CD44 in the cancer cells and those of podoplanin, CA-IX, CD10, and CD44 in the CAFs to evaluate their prognostic value.

RESULTS

Patients with low E-cadherin expression in the cancer cells showed a significantly poorer prognosis than those with high E-cadherin expression in the cancer cells ( P , .001). On the other hand, high podoplanin expression in the CAFs was also associated with a significantly poorer prognosis ( P , .001). A multivariate analysis identified low E-cadherin expression in the cancer cells and high podoplanin expression in the CAFs as significantly independent prognostic factors for overall survival ( P 5 .013 and P 5 .0011, respectively). According to subgroup analyses combining E-cadherin expression in cancer cells and podoplanin expression in CAFs, 5-year overall survival of patients with low E-cadherin expression in the cancer cells and high podoplanin expression in the CAFs was 7.0% and showed a significantly poorer prognosis as compared with other groups ( P , .001).

CONCLUSIONS

The current study indicates that immunophenotypes of CAFs could have a prognostic value independent of those of the cancer cells in SqCC.

[Epithelial-mesenchymal transition in non-small cell lung cancer]

Non-small cell lung carcinoma (NSCLC) is a highly fibrotic malignancy, which exhibits a prominent desmoplastic stroma. Epithelial-mesenchymal transition (EMT) is one of the main modes of carcinoma invasion. We identified the stromal N-glycoprotein periostin by mass spectrometry of lung adenocarcinoma pleural effusions. Validation on a NSCLC tissue microarray and on tumor whole sections by immunohistochemistry indicated that periostin is strongly upregulated at the invasive front in both tumor epithelia and the surrounding matricellular space. In comparison to collagen, elastin and vimentin, periostin was found to be most closely associated with parameters of tumor progression such as larger size and higher stage, with the squamous cell histotype, and with decreased survival. An association with decreased survival was also found for the cell adhesion molecule L1CAM. In conclusion, enlargement of NSCLC tumors is associated with an increase of desmoplastic stroma and concomitant upregulation of EMT markers at the invasive front. The tumor-stroma interface may be a candidate topographic region for stroma- or EMT-directed therapy.

Immune alterations and emerging immunotherapeutic approaches in lung cancer

INTRODUCTION

Subjects with lung cancer were shown to present a variety of immune abnormalities including cellular immune dysfunction, cytokine alterations, and antigen presentation defects. As discouraging results are commonly seen with the existing therapies in lung cancer, more innovative treatment strategies are needed.

AREAS COVERED

The authors review comprehensively the immune abnormalities in individuals with lung cancer, describe the lung cancer immunotherapy candidates that are most advanced in their clinical development, and summarize recent data from clinical trials of these agents.

EXPERT OPINION

Enhancing the immune system represents an appealing avenue for lung cancer therapy. Several immunomodulating agents have activity in this regard including ipilimumab, a monoclonal antibody against the CTLA-4, and talactoferrin, a dendritic cell activator. In addition, a significant activity was shown with belagenpumatucel-L, a whole-cell-based vaccine that blocks the action of TGF-β2. Other promising vaccines are protein-specific vaccines against tumor antigens such as MAGE-A3, EGF, and MUC1. Although some of these immunotherapies may have lackluster performance as single agents in advanced disease, more impressive results are seen in combination with chemotherapy agents. Given their proven activity in lung cancer, these immunotherapies may soon become a powerful addition to the oncologist's toolbox.