Previous studies have highlighted the importance of an appropriate human epidermal growth factor receptor 2 (HER2) evaluation for the proper identification of patients eligible for treatment with ...anti-HER2 targeted therapies. Today, the relationship remains unclear between the level of HER2 amplification and the outcome of HER2-positive gastric cancer treated with first-line chemotherapy with trastuzumab. The aim of this study was to determine whether the level of HER2 gene amplification determined by the HER2/CEP17 ratio and HER2 gene copy number could significantly predict some benefit in overall survival and response to therapy in advanced gastric cancer treated with trastuzumab-based chemotherapy.
Ninety patients with metastatic gastric cancer treated with first-line trastuzumab-based chemotherapy were studied. The optimal cutoff values for HER2/CEP17 ratio and HER2 gene copy number (GCN) for discriminating positive results in terms of response and prolonged survival were determined using receiver operating characteristic curves analyses.
In this study, a median HER2/CEP17 ratio of 6.11 (95% CI, 2.27 to 21.90) and a median HER2 gene copy number of 11.90 (95% CI, 3.30 to 43.80) were found. A mean HER2/CEP17 ratio of 4.7 was identified as the optimal cutoff value discriminating sensitive and refractory patients (P = .005). Similarly, the optimal cutoff for predicting survival longer than 12 months was 4.45 (P = .005), and for survival longer than 16 months was 5.15 (P = .004). For HER2 GCN, the optimal cutoff values were 9.4, 10.0, and 9.5, respectively (P = .02).
The level of HER2 gene amplification significantly predicts sensitivity to therapy and overall survival in advanced gastric cancer treated with trastuzumab-based chemotherapy.
Lung cancer continues to be the leading cause of cancer mortality and a serious health problem despite the numerous advances made in the last decade and the rapid advance of research in this field. ...In recent years, there has been a decrease in mortality from lung cancer coinciding with the approval times of targeted therapy. To date, targeted therapy has been used in the context of advanced disease in clinical practice, with great benefits in survival and quality of life. The next step will be to incorporate targeted therapy into the treatment of earlier stages of non-small-cell lung cancer, and there is already a randomized trial showing a disease-free survival benefit. However, there are many questions that need to be resolved first. In the present review, the authors discuss the findings of published reports and ongoing clinical trials assessing the role of targeted therapies in nonmetastatic disease.
Aims
To study programmed death ligand 1 (PD‐L1) expression, tumour‐infiltrating T lymphocytes (TILs) and the molecular context in patients with early‐stage squamous cell lung carcinomas (SCCs).
...Methods and results
The study included samples from 40 patients (discovery cohort) and 29 patients (validation cohort) diagnosed with early‐stage SCC. PD‐L1 immunohistochemistry (IHC) was performed with three commercially available clones (E1L3N, SP263 and SP142). CD8+ TILs were scored with a digital algorithm. All tumours were analysed with targeted next‐generation sequencing (NGS). Additionally, TP53 mutations were investigated with direct sequencing. In both cohorts, we observed a significant association between CD8+ TILs density and high PD‐L1 IHC expression in tumour cells (TCs). Furthermore, high SP142 PD‐L1 expression in immune cells (ICs) was also associated significantly with CD8+ TILs density. Therefore, CD8+ TILs density discriminated between patients with high versus low PD‐L1 IHC expression with excellent sensitivity and specificity. Interestingly, the highest percentages of PD‐L1‐positive TCs with the three antibodies were found in samples with cyclin‐dependent kinase 6 (CDK6) amplification, with high amplification of proto‐oncogene C‐Myc (CMYC) or with cyclin D1–PI3 kinase subunit alpha (CCND1–PIK3CA) co‐amplification. High SP142 PD‐L1 IHC expression in ICs showed a non‐significant correlation with TP53 mutations. Conversely, most cases with fibroblast growth factor receptor 1 (FGFR1) amplification were negative for all PD‐L1 clones.
Conclusions
Our preliminary results support the use of digital CD8+ TILs scoring and targeted NGS alongside PD‐L1 expression. The approach presented herein could help define patients with SCCs candidates to immune checkpoints inhibitors.
Cancer genomics and translational medicine rely on the molecular profiling of patient's tumor obtained during surgery or biopsy. Alternatively, blood is a less invasive source of tumor DNA shed, ...amongst other ways, as cell-free DNA (cfDNA). Highly-sensitive assays capable to detect cancer genetic events from patient's blood plasma became popularly known as liquid biopsy (LqB). Importantly, retrospective studies including small number of selected patients with metastatic colorectal cancer (mCRC) patients treated with anti-EGFR therapy have shown LqB capable to detect the acquired clonal mutations in RAS genes leading to therapy resistance. However, the usefulness of LqB in the real-life clinical monitoring of these patients still lack additional validation on controlled studies. In this context, we designed a prospective LqB clinical trial to monitor newly diagnosed KRAS wild-type (wt) mCRC patients who received a standard FOLFIRI-cetuximab regimen. We used BEAMing technique for evaluate cfDNA mutations in KRAS, NRAS, BRAF, and PIK3CA in twenty-five patients during a 2-y period. A total of 2,178 cfDNA mutation analyses were performed and we observed that: a) continued wt circulating status was correlated with a prolonged response; b) smoldering increases in mutant cfDNA were correlated with acquired resistance; while c) mutation upsurge/explosion anticipated a remarkable clinical deterioration. The current study provides evidences, obtained for the first time in an unbiased and prospective manner, that reinforces the utility of LqB for monitoring mCRC patients.
The tumor suppressor gene, SMARCA4 (or BRG1), which encodes the ATPase component of the chromatin remodeling complex SWI/SNF, is commonly inactivated by mutations and deletions in lung cancer cell ...lines. However, SMARCA4 alterations appear to be rare in lung primary tumors. Ultra-deep sequencing technologies provide a promising alternative to achieve a sensitivity superior to that of current sequencing strategies. Here we used ultra-deep pyrosequencing to screen for mutations over the entire SMARCA4 coding region in 12 lung tumors without detectable BRG1 protein. While automatic-fluorescence-based sequencing detected one somatic mutation (p.K586X), the pyrosequencing revealed additional variants, thus increasing the sensitivity. One of the variants, which affected a consensus splice site, was confirmed by individual cloning of PCR products, ruling out the possibility of PCR or pyrosequencing artifacts. This mutation, confirmed to be somatic, was present at a frequency of ten percent, suggesting normal cell contamination in the tumor. Our analysis also allowed us to determine the sensitivity and to identify some limitations of the technology. In conclusion, in addition to cell lines, SMARCA4 is biallelically inactivated in a significant proportion of lung primary tumors, thereby constituting one of the most important genes contributing to the development of this type of cancer.
Growth factor receptors (GFRs) are amenable to therapeutic intervention in cancer and it is important to select patients appropriately. One of the mechanisms for activation of GFRs is gene ...amplification (GA) but discrepancies arising from the difficulties associated with data interpretation and the lack of agreed parameters confound the comparison of results from different laboratories. Here, we attempt to establish appropriate conditions for standardization of the determination of GA in a panel of GFRs. A NSCLC tissue microarray panel containing 302 samples was screened for alterations at ALK, FGFR1, FGFR2, FGFR3, ERBB2, IGF1R, KIT, MET and PDGFRA by FISH, immunostaining and/or real‐time quantitative RT‐PCR. Strong amplification was found for FGFR1, ERBB2, KIT/PDFGRA and MET, with frequencies ranging from 1 to 6%. Thresholds for overexpression and GA were established. Strong immunostaining was found in most tumors with ERBB2, MET and KIT amplification, although some tumors underwent strong immunostaining in the absence of GA. KIT and PDFGRA were always coamplified, but only one tumor showed PDGFRA overexpression, indicating that KIT is the main target. Amplification of FGFR1 predominated in squamous cell carcinomas, although the association with overexpression was inconclusive. Interestingly, alterations at ALK, MET, EGFR, ERBB2 and KRAS correlated with augmented levels of phospho‐S6 protein, suggesting activation of the mTOR pathway, which may prove useful to pre‐select tumors for testing. Overall, here, we provide with parameters for the determination of GA at ERBB2, MET, KIT and PDGFRA which could be implemented in the clinic to stratify lung cancer patients for specific treatments.
What's new?
Targeting growth factor receptors is a good way to treat cancer, in the right patients. Therefore, it's important to be able to identify patients with alterations in relevant GFRs. One way they get activated is by gene amplification, but it can be tricky to establish whether amplification has taken place. This study provides the first comprehensive analysis of gene copy number and gene expression alteration in non‐small cell lung carcinoma (NSCLC). By combining the analyses of alterations at the DNA, mRNA, and protein levels for certain growth factors in a panel of 300 NSCLC, the authors were able to identify those tumors that carry gene amplifications. These new results establish parameters for gene amplification that will be useful for routine screening.
The HMG box transcription factor SOX4 involved in neuronal development is amplified and overexpressed in a subset of lung cancers, suggesting that it may be a driver oncogene. In this study, we ...sought to develop this hypothesis including by defining targets of SOX4 that may mediate its involvement in lung cancer. Ablating SOX4 expression in SOX4-amplified lung cancer cells revealed a gene expression signature that included genes involved in neuronal development such as PCDHB, MYB, RBP1, and TEAD2. Direct recruitment of SOX4 to gene promoters was associated with their upregulation upon ectopic overexpression of SOX4. We confirmed upregulation of the SOX4 expression signature in a panel of primary lung tumors, validating their specific response by a comparison using embryonic fibroblasts from Sox4-deficient mice. Interestingly, we found that small cell lung cancer (SCLC), a subtype of lung cancer with neuroendocrine characteristics, was generally characterized by high levels of SOX2, SOX4, and SOX11 along with the SOX4-specific gene expression signature identified. Taken together, our findings identify a functional role for SOX genes in SCLC, particularly for SOX4 and several novel targets defined in this study.
Highlights • HER2 positive gastric cancer is associated with a specific phenotype. • Reliable HER2 testing is mandatory for the correct use of anti-HER2 treatment. • We review present HER2 diagnosis ...and directed therapies in gastric cancer. • Future strategies for HER2 gastric cancer treatment are discussed.
Pancreatic ductal adenocarcinoma (PDA) is an aggressive malignancy with one of the worst outcomes among all cancers. PDA often recurs after initial treatment to result in patient death despite the ...use of chemotherapy or radiation therapy. PDA contains a subset of tumor-initiating cells capable of extensive self-renewal known as cancer stem cells (CSC), which may contribute to therapeutic resistance and metastasis. At present, conventional chemotherapy and radiotherapy are largely ineffective in depleting CSC pool, suggesting the need for novel therapies that specifically target the cancer-sustaining stem cells for tumor eradication and to improve the poor prognosis of PDA patients. In this study, we report that death receptor 5 (DR5) is enriched in pancreatic CSCs compared with the bulk of the tumor cells. Treating a collection of freshly generated patient-derived PDA xenografts with gemcitabine, the first-line chemotherapeutic agent for PDA, is initially effective in reducing tumor size, but largely ineffective in diminishing the CSC populations, and eventually culminated in tumor relapse. However, a combination of tigatuzumab, a fully humanized DR5 agonist monoclonal antibody, with gemcitabine proved to be more efficacious by providing a double hit to kill both CSCs and bulk tumor cells. The combination therapy produced remarkable reduction in pancreatic CSCs, tumor remissions, and significant improvements in time to tumor progression in a model that is considered more difficult to treat. These data provide the rationale to explore the DR5-directed therapies in combination with chemotherapy as a therapeutic option to improve the current standard of care for pancreatic cancer patients.
KRAS mutations represent one of the most prevalent oncogenic driver mutations in non-small cell lung cancer (NSCLC). For many years we have unsuccessfully addressed KRAS mutation as a unique disease. ...The recent widespread use of comprehensive genomic profiling has identified different subgroups with prognostic implications. Moreover, recent data recognizing the distinct biology and therapeutic vulnerabilities of different KRAS subgroups have allowed us to explore different treatment approaches. Small molecules that selectively inhibit KRAS G12C or use of immune checkpoint inhibitors based on co-mutation status are some examples which anticipate that personalized treatment for this challenging disease is finally on the horizon.
PDF
