Towards precision oncology for HER2 blockade in gastroesophageal adenocarcinoma

Gastroesophageal adenocarcinoma (GEA) represents a very heterogeneous disease and patients in advanced stages have a very poor prognosis. Although several molecular classifications have been proposed, precision medicine for HER2-amplified GEA patients still represents a challenge. Despite improvement in clinical outcomes obtained by adding trastuzumab to first-line platinum-based chemotherapy, no other anti-HER2 agents used first-line or beyond progression have demonstrated any benefit. Several factors contribute to this failure. Among them, variable HER2 amplification assessment, tumour heterogeneity, molecular mechanisms of resistance and microenvironmental factors could limit the effecti…

Precision Medicine to Treat Advanced Gastroesophageal Adenocarcinoma: A Work in Progress

Gastroesophageal adenocarcinoma (GEA) represents a heterogeneous disease and, when diagnosed as locally advanced or metastatic, it is characterized by poor prognosis. During the last few years, several molecular classifications have been proposed to try to personalize treatment for those patients diagnosed with advanced disease. Nevertheless, despite the great effort, precision medicine is still far from being a reality. The improvement in the molecular analysis due to the application of high throughput technologies based on DNA and RNA sequencing has opened a novel scenario leading to the personalization of treatment. The possibility to target epidermal growth factor receptor (HER)2, Claud…

Current questions for the treatment of advanced gastric cancer.

Abstract Background Gastric cancer remains a major health problem worldwide. Treatment of advanced gastric cancer is controversial and there is no standard regimen for first- or second-line chemotherapy (CT). This review aims to give an overview of the hot topics concerning treatment, prognostic factors and new strategies in advanced gastric cancer. Material and methods Seven questions of special clinical interest have been formulated previously to the literature review. With the aim of answering each of these questions, a specific search of the relevant trials and meta-analyses published or communicated from 1990 to date was performed. Results Patients treated with CT have a survival benef…

Circulating Tumor DNA in Stage III Colorectal Cancer, beyond Minimal Residual Disease Detection, toward Assessment of Adjuvant Therapy Efficacy and Clinical Behavior of Recurrences

Abstract Purpose: Sensitive methods for risk stratification, monitoring therapeutic efficacy, and early relapse detection may have a major impact on treatment decisions and patient management for stage III colorectal cancer patients. Beyond assessing the predictive power of postoperative ctDNA detection, we explored the added benefits of serial analysis: assessing adjuvant chemotherapy (ACT) efficacy, early relapse detection, and ctDNA growth rates. Experimental Design: We recruited 168 patients with stage III colorectal cancer treated with curative intent at Danish and Spanish hospitals between 2014 and 2019. To quantify ctDNA in plasma samples (n = 1,204), 16 patient-specific somatic sing…

Correlation between classical prognostic factors and overexpression of HER2 and HER3 in localized gastric cancer

e14589 Background: Although HER2 overexpression has been identified as a predictive factor for targeted therapy in advanced gastric cancer (GC), little is known about its role in localized GC. Recent studies suggest that not only HER2 but also HER3 might have a role in prognosis in GC. Our study aimed to identify the prevalence of HER2 and HER3 overexpression in a series of localized GC and to describe correlations of these with traditional prognostic factors Methods: We performed a retrospective analysis of HER2 and HER3 overexpression in archived tumour samples in pts diagnosed with GC at stage I-III. HER2 was assessed with herceptest, (negative if 0 or 1+, or positive with 2+ or 3+). St…

In the literature: August 2020.

Immune checkpoint inhibitors (ICI) have become a key component of therapy for several solid tumours. In patients diagnosed with advanced clear cell renal cell carcinoma (ccRCC), immunotherapy has always been considered as a treatment option, and anti-PD-1-based therapies are approved in both the frontline and refractory settings. Response to PD-1 blockade has been associated with numerous tumour-intrinsic and microenvironment features. Genetic characterisation of ccRCC has significantly contributed to the knowledge of tumour biology and the mechanisms of disease progression, but the interplay of genomic alterations with patterns of immune infiltration in response to PD-1 blockade remains un…

KRAS and BRAF mutations in circulating tumour DNA from locally advanced rectal cancer

There are limited data on circulating, cell-free, tumour (ct)DNA analysis in locally advanced rectal cancer (LARC). Digital droplet (dd)PCR was used to investigate KRAS/BRAF mutations in ctDNA from baseline blood samples of 97 LARC patients who were treated with CAPOX followed by chemoradiotherapy, surgery and adjuvant CAPOX ± cetuximab in a randomised phase II trial. KRAS mutation in G12D, G12V or G13D was detected in the ctDNA of 43% and 35% of patients with tumours that were mutant and wild-type for these hotspot mutations, respectively, according to standard PCR-based analyses on tissue. The detection rate in the ctDNA of 10 patients with less common mutations was 50%. In 26 cases ctDNA…

In the literature: April 2020

Deficient DNA mismatch repair (dMMR) may be caused by germline or somatic mutations in mismatch repair genes ( MLH1 , MSH2 , MSH3 , MSH6 and PMS2 ) or through epigenetic silencing of MLH1 .1 dMMR induces a hypermutator phenotype, also known as microsatellite instability (MSI). Next-generation sequencing identifies MSI in 12 cancer types. The highest prevalence is seen in endometrial cancer (31.4%), followed by colorectal cancer (19.7%) and gastric cancer (GC, 19.1%). MSI was related to better prognosis for colorectal cancer and GC . Moreover, the dMMR/MSI hypermutator phenotype is thought to produce large numbers of immunogenic neoantigens that can be recognised by immune cells, leading to …

Assessing molecular subtypes of gastric cancer: microsatellite unstable and Epstein-Barr virus subtypes. Methods for detection and clinical and pathological implications.

Background The molecular classification of gastric cancer recognises two subtypes prone to immune checkpoint blockade: the microsatellite unstable and the Epstein-Barr virus (EBV)-related tumours. We aim to assess the concordance between immunohistochemistry and PCR for microsatellite status evaluation, and explore the value of microsatellite instability (MSI) and EBV as predictive survival factors. Material and methods We collected 246 consecutively diagnosed gastric cancer cases in all stages and evaluated the microsatellite status using immunohistochemistry for mismatched repair (MMR) proteins and PCR. EBV expression was studied through in situ hybridisation. Results Forty-five (18%) cas…

Circulating Tumor DNA Detection by Digital-Droplet PCR in Pancreatic Ductal Adenocarcinoma: A Systematic Review

Simple Summary Pancreatic cancer is a digestive tumor that is most difficult to treat and carries one of the worst prognoses. The anatomical location of the pancreas makes it very difficult to obtain enough tumor material to establish a molecular diagnosis, so knowing the biology of this tumor and implementing new targeted-therapies is still a pending issue. The use of liquid biopsy, a blood sample test to detect circulating-tumor DNA fragments (ctDNA), is key to overcoming this difficulty and improving the evolution of this tumor. Liquid biopsies are equally representative of the tissue from which they come and allow relevant molecular and diagnostic information to be obtained in a faster …

Serial circulating tumor DNA analysis to assess recurrence risk, benefit of adjuvant therapy, growth rate and early relapse detection in stage III colorectal cancer patients

3540 Background: Challenges in the postoperative management of stage III colorectal cancer include: 1) selection of high-risk patients for adjuvant chemotherapy (ACT), 2) lack of markers to assess ACT efficacy, 3) assessment of recurrence risk after ACT, and 4) lack of markers to guide treatment decisions for high-risk patients e.g. additional therapy or intensified surveillance. Circulating tumor DNA (ctDNA) is a promising marker with potential to mitigate the challenges. Here we used serial ctDNA measurements to assess the correlation between recurrence and ctDNA detection: postoperative, during and after ACT, and during surveillance; and to assess growth rates of metachronous metastases…

Detection of postoperative plasma circulating tumour DNA and lack of CDX2 expression as markers of recurrence in patients with localised colon cancer

BACKGROUND: Colon cancer (CC) is a heterogeneous disease. Novel prognostic factors beyond pathological staging are required to accurately identify patients at higher risk of relapse. Integrating these new biological factors, such as plasma circulating tumour DNA (ctDNA), CDX2 staining, inflammation-associated cytokines and transcriptomic consensus molecular subtypes (CMS) classification, into a multimodal approach may improve our accuracy in determining risk of recurrence.; METHODS: One hundred and fifty patients consecutively diagnosed with localised CC were prospectively enrolled in our study. ctDNA was tracked to detect minimal residual disease by droplet digital PCR. CDX2 expression was…

Low miR200c expression in tumor budding of invasive front predicts worse survival in patients with localized colon cancer and is related to PD-L1 overexpression

At the histological level, tumor budding in colon cancer is the result of cells undergoing at least partial epithelial-to-mesenchymal transition. The microRNA 200 family is an important epigenetic driver of this process, mainly by downregulating zinc-finger E-box binding homeobox (ZEB) and transforming growth factor beta (TGF-β) expression. We retrospectively explored the expression of the miR200 family, and ZEB1 and ZEB2, and their relationship with immune resistance mediated through PD-L1 overexpression. For this purpose, we analyzed a series of 125 colon cancer cases and took samples from two different tumor sites: the area of tumor budding at the invasive front and from the tumor center…

In the literature: October 2019

Gastrointestinal cancers are a subset of molecularly heterogeneous diseases. In the era of personalised medicine, major efforts are being made towards stratifying patients according to molecular profiling. However, although most treatments are currently based on targeted therapy in relation to specific genomic alterations, acquired resistance emerges during anticancer therapies and subsequently treatment failure occurs. Intratumour heterogeneity plays a significant role in the acquisition of resistance by clonal evolution of tumour cell populations under therapeutic pressure. Despite a single tumour biopsy represents the standard for cancer research and drives our therapeutic decisions, lim…

ZNF518B gene up-regulation promotes dissemination of tumour cells and is governed by epigenetic mechanisms in colorectal cancer

AbstractMost of colorectal cancer CRC-related death is due to metastasis and the finding of markers for prognosis of invasiveness, constitutes an appealing challenge. Here, after analysing cDNA array containing 43 tumour and 5 normal mucosa samples, we report that the expression of the ZNF518B gene as a whole and that of its two major splicing isoforms are significantly increased in tumours. The canonical isoform was also up-regulated in a patients’ cohort containing 70 tumour and 69 adjacent tissue samples. The effects of silencing ZNF518B on the phenotype of CRC cell lines were then studied. The gene does not affect cell proliferation, but plays a significant role in cell migration and in…

Why Do We Have to Use Chemotherapy?

The use of chemotherapy (CT) in localized rectal cancer (LARC) has two aims: first, to improve the local effect of radiotherapy by giving concomitant chemoradiation and second, to decrease systemic relapses by early treatment for occult micrometastatic disease or to shrink bulky local tumours. Neoadjuvant treatment is reserved for locally advanced disease, as defined by pelvic magnetic resonance imaging, a very useful and accurate tool to identify high-risk features for local or systemic relapse [1]. We are going to address why we have to use CT in LARC.

Analytical Validation of Multiplex Biomarker Assay to Stratify Colorectal Cancer into Molecular Subtypes

International audience; Previously, we classified colorectal cancers (CRCs) into five CRCAssigner (CRCA) subtypes with different prognoses and potential treatment responses, later consolidated into four consensus molecular subtypes (CMS). Here we demonstrate the analytical development and validation of a custom NanoString nCounter platform-based biomarker assay (NanoCRCA) to stratify CRCs into subtypes. To reduce costs, we switched from the standard nCounter protocol to a custom modified protocol. The assay included a reduced 38-gene panel that was selected using an in-house machine-learning pipeline. We applied NanoCRCA to 413 samples from 355 CRC patients. From the fresh frozen samples (n…

Abstract CT263: Post-surgical liquid biopsy-guided treatment of stage III and high-risk stage II colon cancer patients: The PEGASUS trial

Abstract Background: Moving stage III Colon Cancer (CC) into the precision medicine space is a priority in view of the lack of molecular markers driving adjuvant treatment. Retrospective studies have demonstrated the tremendous prognostic impact of circulating tumor DNA (ctDNA) analysis after curative intent surgery, and suggested that lack of conversion of ctDNA from detectable to undetectable after adjuvant chemotherapy reflects treatment failure. With these premises, we have designed the PEGASUS trial (EudraCT 2019-002074-32) to prove the feasibility of using liquid biopsy to guide the post-surgical and post-adjuvant clinical management of early colon cancer patients. Methods: PEGASUS is…

Targeted next-generation sequencing of circulating-tumor DNA for tracking minimal residual disease in localized colon cancer.

A high percentage of patients diagnosed with localized colon cancer (CC) will relapse after curative treatment. Although pathological staging currently guides our treatment decisions, there are no biomarkers determining minimal residual disease (MRD) and patients are at risk of being undertreated or even overtreated with chemotherapy in this setting. Circulating-tumor DNA (ctDNA) can to be a useful tool to better detect risk of relapse.One hundred and fifty patients diagnosed with localized CC were prospectively enrolled in our study. Tumor tissue from those patients was sequenced by a custom-targeted next-generation sequencing (NGS) panel to characterize somatic mutations. A minimum varian…

“Are There New Chemotherapy Drugs Behind the Corner?”

Up to now, the backbone of both adjuvant and palliative chemotherapy for colorectal cancer is still represented by 5-fluorouracil (5FU). However, we have currently several approved drugs with significant clinical activity in metastatic colon cancer. Apart from cytotoxics such as oxaliplatin, irinotecan, and fluoropyrimidines, we have antiangiogenics (bevacizumab, aflibercept, and ramucirumab), anti-epidermal growth factor receptor (EGFR), and tyrosine kinase inhibitors such as regorafenib. Despite remarkable prolongation of median survival, exceeding 24 months, most patients will be progressing over different lines of therapy, and there is a need and a role for new compounds to be added to …

Clinical pharmacokinetics and pharmacodynamics of ramucirumab in the treatment of colorectal cancer

Colorectal cancer is the third most common cancer worldwide. The prognosis of colorectal cancer patients still remains dismal and half of them will develop metastatic disease. Angiogenesis plays an essential role in colorectal tumorigenesis, and the VEGF pathway is one of the targets that has been validated up to now. The use of antiangiogenics along with chemotherapy has become an accepted standard for colorectal cancer.This review discusses the efficacy and safety profile of ramucirumab, a fully human immunoglobulin G1 monoclonal antibody against the vascular endothelial growth factor receptor-2 (VEGFR-2), for the treatment of second-line metastatic colorectal cancer upon progression to f…

In the literature: December 2020

NRF2 through RPS6 Activation Is Related to Anti-HER2 Drug Resistance in HER2-Amplified Gastric Cancer

Abstract Purpose: Despite the clinical advantage of the combination of trastuzumab and platinum-based chemotherapy in HER2-amplified tumors, resistance will eventually develop. The identification of molecular mechanisms related to primary and acquired resistance is needed. Experimental Design: We generated lapatinib- and trastuzumab-resistant clones deriving from two different HER2-amplified gastric cancer cell lines. Molecular changes such as protein expression and gene-expression profile were evaluated to detect alterations that could be related to resistance. Functional studies in vitro were corroborated in vivo. The translational relevance of our findings was verified in a patient cohor…

Deregulation of ARID1A, CDH1, cMET and PIK3CA and target-related microRNA expression in gastric cancer.

Genetic and epigenetic alterations play an important role in gastric cancer (GC) pathogenesis. Aberrations of the phosphatidylinositol-3-kinase signaling pathway are well described. However, emerging genes have been described such as, the chromatin remodeling gene ARID1A. Our aim was to determine the expression levels of four GC-related genes, ARID1A, CDH1, cMET and PIK3CA, and 14 target-related microRNAs (miRNAs). We compared mRNA and miRNA expression levels among 66 gastric tumor and normal adjacent mucosa samples using quantitative real-time reverse transcription PCR. Moreover, ARID1A, cMET and PIK3CA protein levels were assessed by immunohistochemistry (IHC). Finally, gene and miRNAs as…

Short-term outcomes of colorectal cancer surgery in older patients : a novel nomogram predicting postoperative morbi-mortality

Abstract Purpose To analyze short-term outcomes of curative-intent cancer surgery in all adult patients diagnosed with colorectal cancer undergoing surgery from January 2010 to December 2019 and determine risk factors for postoperative complications and mortality. Methods Retrospective study conducted at a single tertiary university institution. Patients were stratified by age into two groups: < 75 years and ≥ 75 years. Primary outcome was the influence of age on 30-day complications and mortality. Independent risk factors for postoperative adverse events or mortality were analyzed, and two novel nomograms were constructed. Results Of the 1486 patients included, 580 were older (≥ 75 year…

EPDR1 up-regulation in human colorectal cancer is related to staging and favours cell proliferation and invasiveness

The finding of novel molecular markers for prediction or prognosis of invasiveness in colorectal cancer (CRC) constitutes an appealing challenge. Here we show the up-regulation of EPDR1 in a prospective cohort of 101 CRC patients, in a cDNA array of 43 patients and in in silico analyses. EPDR1 encodes a protein related to ependymins, a family of glycoproteins involved in intercellular contacts. A thorough statistical model allowed us to conclude that the gene is significantly up-regulated in tumour tissues when compared with normal mucosa. These results agree with those obtained by the analysis of three publicly available databases. EPDR1 up-regulation correlates with the TNM staging parame…

Personalized Medicine: Recent Progress in Cancer Therapy

Translational research has revolutionized how we develop new treatments for cancer patients. The change from an organ-centric concept guiding treatment choice towards deep molecular analysis, driving a personalized approach, is one of the most important advances of modern oncology. Several tools such as next generation sequencing and RNA sequencing have greatly improved the capacity to detect predictive and prognostic molecular alterations. Detection of gene mutations, amplifications, and fusions has therefore altered the history of several diseases in both a localized and metastatic setting. This shift in perspective, in which attention is focused on the specific molecular alterations of t…

KRAS and BRAF mutations in circulating tumour DNA from locally advanced rectal cancer.

Abstract There are limited data on circulating, cell-free, tumour (ct)DNA analysis in locally advanced rectal cancer (LARC). Digital droplet (dd)PCR was used to investigate KRAS/BRAF mutations in ctDNA from baseline blood samples of 97 LARC patients who were treated with CAPOX followed by chemoradiotherapy, surgery and adjuvant CAPOX ± cetuximab in a randomised phase II trial. KRAS mutation in G12D, G12V or G13D was detected in the ctDNA of 43% and 35% of patients with tumours that were mutant and wild-type for these hotspot mutations, respectively, according to standard PCR-based analyses on tissue. The detection rate in the ctDNA of 10 patients with less common mutations was 50%. In 26 ca…

Neoadjuvant Chemotherapy in Locally Advanced Rectal Cancer

Simple Summary The outcome for patients with rectal cancer has significantly improved over the last thirty years. Previously, local relapses in the pelvis occurred in more than one third of all patients with apparently localized tumors. Total mesorectal excision was the first step to improve local control by reducing local relapses to less than 5%. Preoperative radiation, either short-course or long-course with concurrent administration of chemotherapy, was a second important step for reducing local relapses to a minimum, even in locally advanced tumors where a clean surgical resection was not possible or would not be curative. Magnetic resonance imaging is a very useful tool for locoregion…

The role of chemotherapy in localized and locally advanced rectal cancer: A systematic revision

Curative treatment of rectal cancer depends on an optimal surgical resection, with the addition of neoadjuvant radiotherapy (RT) with or without concomitant chemotherapy (ChT) in more advanced tumors. The role of adjuvant ChT is controversial and a more intensified neoadjuvant approach with the addition of ChT before or after RT, or even as single modality, is currently being explored in trials. A systematic review selecting randomised phase II and III trials on the role of ChT in localized rectal cancer was performed. Data show that neoadjuvant ChRT improves locoregional control in resected rectal cancer. Short-course RT (SCRT) could give similar outcomes to ChRT. The addition of oxaliplat…

Gut vascular barrier impairment leads to intestinal bacteria dissemination and colorectal cancer metastasis to liver

Metastasis is facilitated by the formation of a "premetastatic niche," which is fostered by primary tumor-derived factors. Colorectal cancer (CRC) metastasizes mainly to the liver. We show that the premetastatic niche in the liver is induced by bacteria dissemination from primary CRC. We report that tumor-resident bacteria Escherichia coli disrupt the gut vascular barrier (GVB), an anatomical structure controlling bacterial dissemination along the gut-liver axis, depending on the virulence regulator VirF. Upon GVB impairment, bacteria disseminate to the liver, boost the formation of a premetastatic niche, and favor the recruitment of metastatic cells. In training and validation cohorts of C…

The PEGASUS trial: Post-surgical liquid biopsy-guided treatment of stage III and high-risk stage II colon cancer patients.

TPS4124 Background: Moving stage III Colon Cancer (CC) into the precision medicine space is a priority in view of the lack of molecular markers driving adjuvant treatment. Retrospective studies have demonstrated the tremendous prognostic impact of circulating tumor DNA (ctDNA) analysis after curative intent surgery, and suggested that lack of conversion of ctDNA from detectable to undetectable after adjuvant chemotherapy reflects treatment failure. With these premises, we have designed the PEGASUS trial (NCT04259944). Methods: PEGASUS is a prospective multicentric study designed to prove the feasibility of using liquid biopsy (LB) to guide the post-surgical and post-adjuvant clinical manag…

Gene expression changes responsible for lapatinib acquired resistance in HER2 positive gastric cancer cell lines: a microarray analysis

Improving tumour budding evaluation in colon cancer by extending the assessment area in colectomy specimens.

AIMS It is recommended that tumour budding in colon cancer be counted on haematoxylin and eosin-stained sections in a hotspot area of 0.785 mm2 with a ×20 microscope objective. However, tumour buds may be difficult to visualise on haematoxylin and eosin-stained sections, and counting in such a limited area may result in overestimation in cases with focal budding. The aim of this study was to assess the contributions of various factors to improving tumour budding risk stratification: increasing the number of fields counted, using cytokeratin immunostaining, and recording proliferation, the apoptotic index and the emperipoletic index in tumour buds. METHODS AND RESULTS We created an explorato…

Liquid biopsy: another tool towards tailored therapy in colorectal cancer.

Primary paraesophageal Ewing’s sarcoma: an uncommon case report and literature review

Ewing’s sarcoma is a rare and highly aggressive cancer most frequently arising in people under 20 years of age. We report an uncommon case of primary paraesophageal Ewing’s sarcoma in a 25-year-old male harboring the infrequent EWSR1/ERG fusion transcript with multiple splice variants coexisting in the same tumor. The patient was totally refractory to chemotherapy and died 17 months after diagnosis. We underscore the need for better understanding of the molecular pathogenesis of the disease and improved systemic therapy options.

Primary paraesophageal Ewing’s sarcoma: an uncommon case report and literature review

Noelia Tarazona,1,* Lara Navarro,2,* Juan Miguel Cejalvo,3,* Valentina Gambardella,3,* J Alejandro Pérez-Fidalgo,3 Alejo Sempere,2 Samuel Navarro,2 Andrés Cervantes31Department of Medicine, GI and Lymphoma Unit, The Royal Marsden NHS Foundation Trust, London and Surrey, UK; 2Department of Pathology, 3Department of Hematology and Medical Oncology, Biomedical Research Institute, INCLIVA, University of Valencia, Valencia, Spain*These authors contributed equally to this workAbstract: Ewing’s sarcoma is a rare and highly aggressive cancer most frequently arising in people under 20 years of age. We report an uncommon case of primary paraesophageal Ewing’s…