Targetable Pathways in the Treatment of Retroperitoneal Liposarcoma

Soft tissue sarcomas at the single-cell and spatial resolution: new markers and targets

Soft tissue sarcomas (STS) are heterogeneous and aggressive tumors, originating in connective tissues embryologically derived from the mesenchyme. Due to their rarity, crucial information about their biology is still lacking. In recent years, single-cell and spatial analyses have opened up new horizons in oncology, leading to the possibility of characterizing the internal architecture of the tumor at the single-cell and spatial levels. This review summarizes the first results acquired through these revolutionary methods for different types of STS. We discuss tumor cell populations and their evolution, interactions between tumor cells and the microenvironment, new prognostic markers, and clinically important targets. Finally, we examine the challenges presented by the single-cell and spatial omics of STS and the future perspectives in this field.

Oncogenic Functions of Alternatively Spliced MDM2-ALT2 Isoform in Retroperitoneal Liposarcoma

Retroperitoneal liposarcoma (RPLPS) is one of the most common histologic subtypes of soft tissue sarcoma (STS). Complete surgical resection remains the mainstay treatment, while the high rate of locoregional recurrence constitutes the predominant cause of mortality. Well-differentiated (WDLPS) and dedifferentiated (DDLPS) liposarcoma are the most frequent subtypes of RPLPS and present amplified MDM2 gene as a hallmark. However, there are few reports evaluating the role of alternatively spliced MDM2 transcripts in RPLPS. In this study, we assessed MDM2-ALT2 expression levels in a cohort of RPLPS patients and evaluated the biological functions of the MDM2-ALT2 isoform in vitro in DDLPS cell lines. Using BaseScope™ and qPCR, we demonstrated that MDM2-Full Length (MDM2-FL) and MDM2-ALT2 expression levels were upregulated in RPLPS patient-derived tissue samples compared to normal adjacent to tumor tissue (NAT). DDLPS cells overexpressing MDM2-FL or MDM2-ALT2 had higher proliferation rates and increased migration and invasion capacities, as well as increased protein levels of p-AKT, mTOR, p70S6K, MMP2, and cJun. Simultaneous overexpression of MDM2-ALT2 and AKT silencing showed that AKT inhibition impaired p-p70S6K and MMP2 protein increased levels and led to significantly decreased proliferation and migration rates compared to cells overexpressing MDM2-ALT2 only. Taken together, our data suggest that MDM2-ALT2 may promote RPLPS progression.

Targeting liposarcoma: unveiling molecular pathways and therapeutic opportunities

In recent years, an increasing number of studies have utilized molecular biology techniques to reveal important molecular heterogeneity among different subtypes of liposarcoma. Each subtype exhibits distinct genetic patterns and molecular pathways, which may serve as important targets for molecular therapy. In the present review, we focus on the molecular characteristics, molecular diagnostics, driver genes, and molecular mechanisms of liposarcoma. We also discuss the clinical research progress of related targeted therapies, with an aim to provide a reference and crucial insights for colleagues in the field.

Rare primary dedifferentiated liposarcoma of the thoracic spine: A case report and literature review

Introduction

Primary dedifferentiated liposarcomas of the spine mark a rare tumor entity.

Research question and case description

We present a rare case of a primary dedifferentiated liposarcoma of the thoracic spine. A 36-year-old previously completely healthy woman presented with a sudden ascending paresthesia of both legs, persistently increasing over the course of two days before initial presentation.

Case report

Computed tomography and magnetic resonance imaging revealed an expansively growing tumor mass extending from T5 to T6 and absolutely compressing the dural sac and spinal cord. The patient's neurological function completely recovered after emergency posterior decompression via laminectomy with intralesional tumor debulking. The tumor was histologically classified as primary grade 2 dedifferentiated liposarcoma (DDLPS) of the spine and after referral to a sarcoma center, the patient was treated with three courses of polychemotherapy (doxorubicin plus ifosfamide). Chemotherapy was followed by aggressive resection by en-bloc spondylectomy in cooperation with a spine tumor center. Subsequently, the patient also underwent radiation therapy.

Results

The patient still undergoes structured tumor aftercare and is tumor- and metastasis-free 53 months after tumor resection.

Discussion and conclusion

DDLPS rarely occur in the spine, with definitive resection of the tumor being the treatment of choice. Surgery should be accompanied by other (radio-) oncological treatment options in cases where only subtotal resection is possible. Also, referral of patients with primary sarcomas of the spine to specialized sarcoma centers is essential, so they can be provided with individual treatment options and structured interdisciplinary aftercare, that ensure the best possible outcome.

Exploring the common targets of well-differentiated and dedifferentiated retroperitoneal liposarcoma via gene co-expression analysis

Objective

This study aimed to identify common therapeutic targets for well-differentiated and dedifferentiated retroperitoneal liposarcoma.

Methods

Patient clinical data were obtained from the Surveillance, Epidemiology, and End Results (SEER) database, and survival differences were analyzed using the log-rank test. Gene expression data were sourced from the Gene Expression Omnibus (GEO) dataset GSE159659, with differential gene expression analysis conducted through GEO2R. Protein-protein interaction networks were developed using STRING and Cytoscape to identify key hub genes. Gene Ontology (GO) and KEGG pathway enrichment analyses were performed using R, and transcription factors associated with the hub genes were predicted with TRRUST.

Results

Significant survival differences were found between patients with well-differentiated and dedifferentiated retroperitoneal liposarcoma. Ninety-six differentially expressed genes with similar expression patterns were identified in both types. A protein-protein interaction network highlighted 12 hub genes and 24 transcription factors. Enrichment analysis pointed to the importance of lipid localization, storage, cytokine signaling, and metal ion absorption in both liposarcoma subtypes. Four potential therapeutic drugs were successfully predicted.

Conclusion

This study identifies common molecular targets in well-differentiated and dedifferentiated retroperitoneal liposarcoma, providing new avenues for mechanistic studies and potential therapeutic development.

Primary liposarcoma of the uterus with MDM2 negative

ABSTRACT

Liposarcoma is one of the most common soft-tissue sarcomas that originates from adipose tissue. Primary uterine liposarcoma is extremely rare. With the MDM2, negative is even rarer. We report a 37-year-old woman presented with lower abdominal discomfort and increase in vaginal secretions for more than 2 months. The ultrasonography revealed a hypoechoic mass sized 81 × 73 × 67 mm in the right adnexal area. Histopathologically, the neoplasm was mainly composed of mature adipose tissue, a small number of scattered lipoblasts, and the spindle cell which with mild atypia. Immunohistochemistry showed that the tumor cells were positive for CDK4 but negative for MDM2, and FISH analysis showed no MDM2 amplification. The patient only underwent tumor excision and is currently doing well.

Standardizing Surgical Management of Retroperitoneal Sarcomas: Dawn of a New Surgical Subspeciality in India

BACKGROUND

Retroperitoneal sarcomas are a complex and heterogenous group of tumors. An approach to these tumors should be guided by a clear understanding of the disease biology and anatomical principles, which mandates a dedicated multidisciplinary team approach at all steps of management. We present our experience of evolution as a high-volume sarcoma center with a dedicated multidisciplinary tumor board (the RP clinic) with consequent standardization of surgeries and management protocols.

METHODS

A retrospective analysis of a prospectively maintained database for patients undergoing surgery from January 2011 to June 2023 was performed. Data were divided into the pre-clinic era (2011-2017) and post-clinic era (2018-2023). Survival curves were obtained using the Kaplan-Meier method, and the Chi-square test was used to test significance for categorical variables. Time trends were analyzed using the one-way analysis of variance (ANOVA) test. A p value ≤ 0.05 was considered significant.

RESULTS

Overall, 254 patients were operated during this period; 36.6% of patients underwent surgeries in the pre-RP clinic era (6 years) and 63.3% in the post-RP clinic era (4.5 years). There was a statistically significant increase in the number of cases being operated per year, from an average of 16.3 in the pre-clinic era to 42.4 in the post-RP clinic era (p = 0.001). The post-RP clinic era also showed a significant increase in compartment and multivisceral resections (49% vs. 18.2%; p = 0.0001).

CONCLUSIONS

Establishment of a dedicated multidisciplinary tumor board (RP clinic) resulted in standardization of management protocols, resulting in optimal oncological and surgical outcomes.

Retroperitoneal liposarcoma: unveiling diagnostic delays and multimodal treatment dilemmas

Liposarcomas are a prevalent subtype of soft tissue sarcomas, constituting less than 1% of all malignancies. Originating in the adipose tissue, they can manifest in various locations and are categorized by the World Health Organization into several subtypes: well-differentiated liposarcomas, dedifferentiated liposarcomas, myxoid liposarcomas, pleomorphic liposarcomas and mixed-type liposarcomas. These tumors typically affect middle-aged and older individuals, and their incidence has been progressively increasing over the years. As liposarcomas advance they tend to encase blood vessels and major organs, particularly in the retroperitoneal area. Often asymptomatic initially, symptoms arise as the tumor reaches a considerable size, exerting pressure on adjacent tissues and organs. This report features a 54-year-old patient incidentally diagnosed with a substantial retroperitoneal tumor extending to the antero-lateral abdominal wall and inner thigh via the right inguinal ligament. The patient, with a previous three-year history of a right inguinal mass, sought acute care for a perianal abscess The histological examination revealed morphological aspects consistent with a low-grade myxoid liposarcoma. While surgery remains the primary treatment for retroperitoneal liposarcomas, controversies exist regarding the role of radiotherapy and chemotherapy in improving survival rates. This case highlights the challenges in managing retroperitoneal tumors and underscores the importance of a personalized, multidisciplinary approach to optimize patient outcomes.

Differentially expressed platelet activation-related genes in dogs with stage B2 myxomatous mitral valve disease

BACKGROUND

Peripheral blood carries a reservoir of mRNAs that regulate cardiac structure and function potential. Although it is well recognized that the typical symptoms of Myxomatous Mitral Valve Disease (MMVD) stage B2 are long-standing hemodynamic disorder and cardiac structure remodeling caused by mitral regurgitation, the transcriptomic alterations in blood from such dogs are not understood.

RESULTS

In the present study, comparative high-throughput transcriptomic profiling of blood was performed from normal control (NC) and naturally-occurring MMVD stage B2 (MMVD) dogs. Using Weighted Gene Co-expression Network Analyses (WGCNA), Gene Ontology (GO), and Kyoto Encyclopedia of Gene and Genomes (KEGG), we identified that the turquoise module was the most highly correlated with echocardiographic features and found 64 differentially expressed genes (DEGs) that were significantly enriched in platelet activation related pathways. Therefore, from the turquoise module, we selected five DEGs (MDM2, ROCK1, RIPK1, SNAP23, and ARHGAP35) that, according to real-time qPCR, exhibited significant enrichment in platelet activation related pathways for validation. The results showed that the blood transcriptional abundance of MDM2, ROCK1, RIPK1, and SNAP23 differed significantly (P < 0.01) between NC and MMVD dogs. On the other hand, Correlation Analysis revealed that MDM2, ROCK1, RIPK1, and SNAP23 genes negatively regulated the heart structure parameters, and followed the same trend as observed in WGCNA.

CONCLUSION

We screened four platelet activation related genes, MDM2, ROCK1, RIPK1, and SNAP23, which may be considered as the candidate biomarkers for the diagnosis of MMVD stage B2. These findings provided new insights into MMVD pathogenesis.

Predictors and outcomes of recurrent retroperitoneal liposarcoma with multiple tumors

Background

Retroperitoneal liposarcoma (RLS) is a rare but severe disease. Repeated postoperative recurrence with multiple tumors is a therapeutic dilemma. The clinical outcomes and survival predictors of recurrent RLS with multiple tumors remain to be explored.

Methods

Patients with recurrent RLS were retrospectively analyzed. Univariate and multivariate analysis was performed to find independent prognostic factors that were correlated with Overall survival (OS) or progression-free survival (PFS). Factors significant in univariate analysis were further included into multivariate Cox proportional hazards regression model. The nomogram model was built to predict the survival status of patients. Variables that were significant in multivariable analysis were added to the internally validated nomogram models. The analysis of OS and PFS was performed by Kaplan-Meier analysis and log-rank test.

Results

A total of 113 recurrent RLS patients with multiple tumors were enrolled in the study. The 1-, 3-, and 5-years OS (PFS) rates were 70.7% (76.1%), 35.9% (76.1%), and 30.9% (76.1%), respectively. Univariate and multivariate analyses showed that number of surgeries, resection methods, tumor size, status of pathological differentiation, pathological subtypes, and recurrence patterns were important prognostic factors for OS or PFS (each p < 0.05). Nomogram models were established to efficiently predict the prognostic status of patients. Patients with the local recurrence (LR) pattern had a poor prognosis and would derive no survival benefit from combined organ resection and R0/R1 resection (each p < 0.05).

Conclusion

RLS patients recurrence with multiple tumors had a poor prognosis. Those patients should be followed up more frequently after surgery. The strategies of aggressive resection may not improve the survival of patients with LR pattern in the retroperitoneum. Prognostic factors in the efficient nomogram models should be considered in the individualized clinical management of recurrent RLS with multiple tumors.

Giant myxoid retroperitoneal liposarcoma in a 41-year-old patient: A case report

INTRODUCTION

Retroperitoneal Liposarcomas (RL) are a rare form of malignant tumors, they encompass just 5 % ot these and mainly present in female adults between 50 and 60 years of age. They can be divided into 4 morphological subtypes: 1) well-differentiated, 2) undifferentiated, 3) myxoid, and 4) pleomorphic.

CASE PRESENTATION

41-year-old male who present to the outpatient consult of oncological surgery after being diagnosed via imaging with a giant retroperitoneal liposarcoma. The patient reported unsuccessful weight loss attempts and subsequently noticed an increase in abdominal size as well as the development of ulcers in the lower limbs. He underwent radical resection, which included a right nephrectomy, as the primary treatment.

DISCUSSION

Giant retroperitoneal liposarcomas are defined as those 30 cm in diameter or more or 20 kg or more in weight are considered "giants" and are extremely rare. The only treatment involves resection of the tumoration and those adjacent involved organs, and sometimes, uninvolved ones. Due to the high risk of recurrence, adjuvant therapy may be provided as well as imaging follow up.

CONCLUSION

RL are a complicated entity to manage. They tend to present high rates of recurrence due to the difficulty of performing a full resection without positive margins. These patients should be thoroughly studied before surgery and appropriate follow-up should be provided.

Insight of a lipid metabolism prognostic model to identify immune landscape and potential target for retroperitoneal liposarcoma

Introduction

The exploration of lipid metabolism dysregulation may provide novel perspectives for retroperitoneal liposarcoma (RPLS). In our study, we aimed to investigate potential targets and facilitate further understanding of immune landscape in RPLS, through lipid metabolism-associated genes (LMAGs) based prognostic model.

Methods

Gene expression profiles and corresponding clinical information of 234 cases were enrolled from two public databases and the largest retroperitoneal tumor research center of East China, including cohort-TCGA (n=58), cohort-GSE30929 (n=92), cohort-FD (n=50), cohort-scRNA-seq (n=4) and cohort-validation (n=30). Consensus clustering analysis was performed to identify lipid metabolism-associated molecular subtypes (LMSs). A prognostic risk model containing 13 LMAGs was established using LASSO algorithm and multivariate Cox analysis in cohort-TCGA. ESTIMATE, CIBERSORT, XCELL and MCP analyses were performed to visualize the immune landscape. WGCNA was used to identify three hub genes among the 13 model LMAGs, and preliminarily validated in both cohort-GSE30929 and cohort-FD. Moreover, TIMER was used to visualize the correlation between antigen-presenting cells and potential targets. Finally, single-cell RNA-sequencing (scRNA-seq) analysis of four RPLS and multiplexed immunohistochemistry (mIHC) were performed in cohort-validation to validate the discoveries of bioinformatics analysis.

Results

LMS1 and LMS2 were characterized as immune-infiltrated and -excluded tumors, with significant differences in molecular features and clinical prognosis, respectively. Elongation of very long chain fatty acids protein 2 (ELOVL2), the enzyme that catalyzed the elongation of long chain fatty acids, involved in the maintenance of lipid metabolism and cellular homeostasis in normal cells, was identified and negatively correlated with antigen-presenting cells and identified as a potential target in RPLS. Furthermore, ELOVL2 was enriched in LMS2 with significantly lower immunoscore and unfavorable prognosis. Finally, a high-resolution dissection through scRNA-seq was performed in four RPLS, revealing the entire tumor ecosystem and validated previous findings.

Discussion

The LMS subgroups and risk model based on LMAGs proposed in our study were both promising prognostic classifications for RPLS. ELOVL2 is a potential target linking lipid metabolism to immune regulations against RPLS, specifically for patients with LMS2 tumors.

Small Non-Coding RNAs in Soft-Tissue Sarcomas: State of the Art and Future Directions

Soft-tissue sarcomas (STS) are a rare and heterogeneous group of tumors that arise from connective tissue and can occur anywhere in the body. Among the plethora of over 50 different STS types, liposarcoma (LPS) is one of the most common. The subtypes of STS are characterized by distinct differences in tumor biology that drive responses to pharmacologic therapy and disparate oncologic outcomes. Small non-coding RNAs (sncRNA) are a heterogeneous class of regulatory RNAs involved in the regulation of gene expression by targeting mRNAs. Among the several types of sncRNAs, miRNAs and tRNA-derived ncRNAs are the most studied in the context of tumor biology, and we are learning more about the role of these molecules as important regulators of STS tumorigenesis and differentiation. However, challenges remain in translating these findings and no biomarkers or therapeutic approaches targeting sncRNAs have been developed for clinical use. In this review, we summarize the current landscape of sncRNAs in the context of STS with an emphasis on LPS, including the role of sncRNAs in the tumorigenesis and differentiation of these rare malignancies and their potential as novel biomarkers and therapeutic targets. Finally, we provide an appraisal of published studies and outline future directions to study sncRNAs in STS, including tRNA-derived ncRNAs.

A large dedifferentiated retroperitoneal liposarcoma extended to the testis: a rare case report

Liposarcomas are neoplasms of mesodermal origin representing less than 1% of all malignant tumors and 1 to 2% of urogenital lesions. Primary retroperitoneal liposarcomas extending into the inguinal canal are rare. We present the case of a large retroperitoneal liposarcoma invading the left testicle and its spermatic cord. It was diagnosed by imaging as a large mass that compresses surrounding abdominal structures and communicating with the inguinal canal. A surgical intervention consisting of en bloc resection of the tumor and the left testicle with its cord was performed by 2 routes, intercostal and inguinal. Histology showed a dedifferentiated liposarcoma, which is a rare entity with a high rate of malignancy and a poor prognosis. The treatment of choice is wide surgical resection with clear margins; chemotherapy and radiotherapy are less sensitive. The patient did not manifest any particular complaints during the first six months after surgery.

New trends in the surgical management of soft tissue sarcoma: The role of preoperative biopsy

Soft tissue sarcoma (STS) accounts for 1% of all malignant neoplasms in adults. Their diagnosis and management constitute a challenging target. They originate from the mesenchyme, and 50 subtypes with various cytogenetic profiles concerning soft tissue and bones have been recognized. These tumors mainly affect middle-aged adults but may be present at any age. Half of the patients have metastatic disease at the time of diagnosis and require systemic therapy. Tumors above 3-5 cm in size must be suspected of potential malignancy. A thorough history, clinical examination and imaging that must precede biopsy are necessary. Modern imaging techniques include ultrasound, computed tomography (CT), new magnetic resonance imaging (MRI), and positron emission tomography/CT. MRI findings may distinguish low-grade from high-grade STS based on a diagnostic score (tumor heterogeneity, intratumoral and peritumoral enhancement). A score ≥ 2 indicates a high-grade lesion, and a score ≤ 1 indicates a low-grade lesion. For disease staging, abdominal imaging is recommended to detect early abdominal or retroperitoneal metastases. Liquid biopsy by detecting genomic material in serum is a novel diagnostic tool. A preoperative biopsy is necessary for diagnosis, prognosis and optimal planning of surgical intervention. Core needle biopsy is the most indicative and effective. Its correct performance influences surgical management. An unsuccessful biopsy means the dissemination of cancer cells into healthy anatomical structures that ultimately affect resectability and survival. Complete therapeutic excision (R0) with an acceptable resection margin of 1 cm is the method of choice. However, near significant structures, i.e., vessels, nerves, an R2 resection (macroscopic margin involvement) preserving functionality but having a risk of local recurrence can be an acceptable choice, after informing the patient, to prevent an unavoidable amputation. For borderline resectability of the tumor, neoadjuvant chemo/radiotherapy has a place. Likewise, after surgical excision, adjuvant therapy is indicated, but chemotherapy in nonmetastatic disease is still debatable. The five-year survival rate reaches up to 55%. Reresection is considered after positive or uncertain resection margins. Current strategies are based on novel chemotherapeutic agents, improved radiotherapy applications to limit local side effects and targeted biological therapy or immunotherapy, including vaccines. Young age is a risk factor for distant metastasis within 6 mo following primary tumor resection. Neoadjuvant radiotherapy lasting 5-6 wk and surgical resection are indicated for high-grade STS (grade 2 or 3). Wide surgical excision alone may be acceptable for patients older than 70 years. However, locally advanced disease requires a multidisciplinary task of decision-making for amputation or limb salvage.

Updates in Pathology for Retroperitoneal Soft Tissue Sarcoma

Retroperitoneal tumors are extremely rare. More than 70% of primary retroperitoneal soft tissue tumors are malignant. The most common sarcomas in the retroperitoneum include liposarcomas and leiomyosarcoma, however other sarcomas, along with benign mesenchymal tumors, can occur. Sarcomas are a heterogenous group of tumors with overlapping microscopic features, posing a diagnostic challenge for the pathologist. Correct tumor classification has become important for prognostication and the evolving targeted therapies for sarcoma subtypes. In this review, the pathology of retroperitoneal soft tissue sarcomas is discussed, which is important to the surgical oncologist. In addition, less common sarcomas and benign mesenchymal tumors of the retroperitoneum, which may mimic sarcoma clinically and pathologically, are also discussed.

Beyond targeting amplified MDM2 and CDK4 in well differentiated and dedifferentiated liposarcomas: From promise and clinical applications towards identification of progression drivers

Well differentiated and dedifferentiated liposarcomas (WDLPS and DDLPS) are tumors of the adipose tissue poorly responsive to conventional cytotoxic chemotherapy which currently remains the standard-of-care. The dismal prognosis of the DDLPS subtype indicates an urgent need to identify new therapeutic targets to improve the patient outcome. The amplification of the two driver genes MDM2 and CDK4, shared by WDLPD and DDLPS, has provided the rationale to explore targeting the encoded ubiquitin-protein ligase and cell cycle regulating kinase as a therapeutic approach. Investigation of the genomic landscape of WD/DDLPS and preclinical studies have revealed additional potential targets such as receptor tyrosine kinases, the cell cycle kinase Aurora A, and the nuclear exporter XPO1. While the therapeutic significance of these targets is being investigated in clinical trials, insights into the molecular characteristics associated with dedifferentiation and progression from WDLPS to DDLPS highlighted additional genetic alterations including fusion transcripts generated by chromosomal rearrangements potentially providing new druggable targets (e.g. NTRK, MAP2K6). Recent years have witnessed the increasing use of patient-derived cell and tumor xenograft models which offer valuable tools to accelerate drug repurposing and combination studies. Implementation of integrated "multi-omics" investigations applied to models recapitulating WD/DDLPS genetics, histologic differentiation and biology, will hopefully lead to a better understanding of molecular alterations driving liposarcomagenesis and DDLPS progression, as well as to the identification of new therapies tailored on tumor histology and molecular profile.

In situ hybridization to detect DNA amplification in extracellular vesicles

EVs have emerged as an important component in tumour initiation, progression and metastasis. Although notable progresses have been made, the detection of EV cargoes remain significantly challenging for researchers to practically use; faster and more convenient methods are required to validate the EV cargoes, especially as biomarkers. Here we show, the possibility of examining embedded EVs as substrates to be used for detecting DNA amplification through ultrasensitive in situ hybridization (ISH). This methodology allows the visualization of DNA targets in a more direct manner, without time consuming optimization steps or particular expertise. Additionally, formalin-fixed paraffin-embedded (FFPE) blocks of EVs allows long-term preservation of samples, permitting future studies. We report here: (i) the successful isolation of EVs from liposarcoma tissues; (ii) the EV embedding in FFPE blocks (iii) the successful selective, specific ultrasensitive ISH examination of EVs derived from tissues, cell line, and sera; (iv) and the detection of MDM2 DNA amplification in EVs from liposarcoma tissues, cell lines and sera. Ultrasensitive ISH on EVs would enable cargo study while the application of ISH to serum EVs, could represent a possible novel methodology for diagnostic confirmation. Modification of probes may enable researchers to detect targets and specific DNA alterations directly in tumour EVs, thereby facilitating detection, diagnosis, and improved understanding of tumour biology relevant to many cancer types.