Digenic Inheritance of Mutations in Homologous Recombination Genes in Cancer Patients.

BACKGROUND/OBJECTIVES: BRCA1, BRCA2, ATM, and CHEK2 are known cancer predisposition genes (CPGs), but tumor risk in patients with simultaneous pathogenic variants (PVs) in CPGs remains largely unknown. In this study, we describe six patients from five families with multiple cancers who coinherited a combination of PVs in these genes. METHODS: PVs were identified using NGS DNA sequencing and were confirmed by Sanger. RESULTS: Families 1, 2, and 3 presented PVs in BRCA2 and ATM, family 4 in BRCA2 and BRCA1, and family 5 in BRCA2 and CHEK2. PVs were identified using NGS DNA sequencing and were confirmed by Sanger. The first family included patients with kidney, prostate, and breast cancer, in addition to pancreatic adenocarcinomas. In the second family, a female had breast cancer, while a male from the third family had prostate, gastric, and pancreatic cancer. The fourth family included a male with pancreatic cancer, and the fifth family a female with breast cancer. CONCLUSIONS: The early age of diagnosis and the development of multiple cancers in the reported patients indicate a very high risk of cancer in double-heterozygous patients associated with PVs in HR-related CPGs. Therefore, in families with patients who differ from other family members in terms of phenotype, age of diagnosis, or type of cancer, the cascade testing needs to include the study of other CPGs.

Case Report Series: Aggressive HR Deficient Colorectal Cancers Related to BRCA1 Pathogenic Germline Variants.

Objective: The link between BRCA1 and homologous recombination deficiency (HRD) in cancer has gained importance with the emergence of new targeted cancer treatments, while the available data on the role of the gene in colorectal cancer (CRC) remain contradictory. The aim of this case series was to elucidate the role of known pathogenic BRCA1 variants in the development of early-onset CRC. Design: Patients were evaluated using targeted next generation sequencing, exome sequencing and chromosomal microarray analysis of the paired germline and tumor samples. These results were used to calculate the HRD score and the frequency of mutational signatures in the tumors. Results: Three patients with metastatic CRC were heterozygous for a previously known BRCA1 nonsense variant. All tumors showed remarkably high HRD scores, and the HRD-related signature 3 had the second highest contribution to the somatic pattern of variant accumulation in the samples (23% in 1 and 2, and 13% in sample 3). Conclusions: A BRCA1 germline pathogenic variant can be involved in CRC development through HRD. Thus, BRCA1 testing should be considered in young patients with a personal history of microsatellite stable CRC as this could further allow a personalized treatment approach.

Oncological patients' reactions to COVID-19 pandemic: A single institution prospective study.

BACKGROUND: The spread of the COVID-19 pandemic has led to a rapid reorganization in all human and hospital activities, with impact on cancer patients. AIM: An analysis of cancer patients fears, and awareness of COVID-19 has been done in this study. METHODS AND RESULTS: We analyzed cancer patients' reactions to the pandemic and their perception of oncological care reorganization, through a 12-item survey, proposed at the peak of pandemic and 3 months later. Overall, 237 patients were included in the study. During the peak of pandemic 34.6% of patients were more worried about COVID-19 than cancer versus 26.4% in the post-acute phase (p = .013). Although 49.8% of patients in the acute phase and 42.3% in the post-acute phase considered their risk of death if infected ≥50%, and more than 70% of patients thought to be at higher risk of complications, the majority of them did not consider the possibility to stop or delay their treatment. Patients were more interested in following news about COVID-19 than cancer and they complied with all preventive measures in more than 90% of the cases. CONCLUSIONS: Although cancer patients worried about COVID-19 and evaluated the risk of complication or death due to COVID-19 as extremely high, they were still asking for the best oncological treatment.

Impact of solid cancer on in-hospital mortality overall and among different subgroups of patients with COVID-19: a nationwide, population-based analysis.

BACKGROUND: Cancer seems to have an independent adverse prognostic effect on COVID-19-related mortality, but uncertainty exists regarding its effect across different patient subgroups. We report a population-based analysis of patients hospitalised with COVID-19 with prior or current solid cancer versus those without cancer. METHODS: We analysed data of adult patients registered until 24 May 2020 in the Belgian nationwide database of Sciensano. The primary objective was in-hospital mortality within 30 days of COVID-19 diagnosis among patients with solid cancer versus patients without cancer. Severe event occurrence, a composite of intensive care unit admission, invasive ventilation and/or death, was a secondary objective. These endpoints were analysed across different patient subgroups. Multivariable logistic regression models were used to analyse the association between cancer and clinical characteristics (baseline analysis) and the effect of cancer on in-hospital mortality and on severe event occurrence, adjusting for clinical characteristics (in-hospital analysis). RESULTS: A total of 13 594 patients (of whom 1187 with solid cancer (8.7%)) were evaluable for the baseline analysis and 10 486 (892 with solid cancer (8.5%)) for the in-hospital analysis. Patients with cancer were older and presented with less symptoms/signs and lung imaging alterations. The 30-day in-hospital mortality was higher in patients with solid cancer compared with patients without cancer (31.7% vs 20.0%, respectively; adjusted OR (aOR) 1.34; 95% CI 1.13 to 1.58). The aOR was 3.84 (95% CI 1.94 to 7.59) among younger patients (<60 years) and 2.27 (95% CI 1.41 to 3.64) among patients without other comorbidities. Severe event occurrence was similar in both groups (36.7% vs 28.8%; aOR 1.10; 95% CI 0.95 to 1.29). CONCLUSIONS: This population-based analysis demonstrates that solid cancer is an independent adverse prognostic factor for in-hospital mortality among patients with COVID-19. This adverse effect was more pronounced among younger patients and those without other comorbidities. Patients with solid cancer should be prioritised in vaccination campaigns and in tailored containment measurements.

Appendiceal neuroendrocrine neoplasms: incidentaloma or something we should worry about?

PURPOSE OF REVIEW: To synthesize the current knowledge and guidelines on the management of appendiceal neuroendocrine neoplasms (ANENs). RECENT FINDINGS: Most recent guidelines are essentially based on heterogeneous retrospective series. With the advent of a more precise classification of neuroendocrine neoplasms, this heterogeneity is rightly criticized and many 'grey areas' are now debated in expert literature. The only way to solve these issues is through the conduct of large prospective multicentre studies, but this seems somewhat utopian, given the rarity of this disease. SUMMARY: ANENs are rare tumours with a favourable prognosis, and mainly diagnosed in young patients. They are predominantly localized, and diagnosed incidentally on appendectomy. This procedure is curative for the vast majority of patients but ANENs can relapse even a significant time after the first diagnosis. Identifying the risks for recurrence is challenging, with some factors thought to be predictive of nodal involvement. The presence of one or more of these factors justifies an oncological radicalization of the surgical procedure (right hemicolectomy with lymphadenectomy). However, the beneficial impact of this surgical procedure on survival is still unproven.

Expression of MT4-MMP, EGFR, and RB in Triple-Negative Breast Cancer Strongly Sensitizes Tumors to Erlotinib and Palbociclib Combination Therapy.

PURPOSE: Here, we investigated the clinical relevance of an unprecedented combination of three biomarkers in triple-negative breast cancer (TNBC), both in human samples and in patient-derived xenografts of TNBC (PDX-TNBC): EGFR, its recently identified partner (MT4-MMP), and retinoblastoma protein (RB).Experimental Design: IHC analyses were conducted on human and PDX-TNBC samples to evaluate the production of the three biomarkers. The sensitivity of cancer cells expressing or not MT4-MMP to anti-EGFR (erlotinib) or anti-CDK4/6 inhibitor (palbociclib) was evaluated in vitro in 2D and 3D proliferation assays and in vivo using xenografts and PDX-TNBC displaying different RB, MT4-MMP, and EGFR status after single (erlotinib or palbociclib) or combined (erlotinib + palbociclib) treatments. RESULTS: EGFR and MT4-MMP were coexpressed in >70% of TNBC samples and PDX-TNBC, among which approximately 60% maintained RB expression. Notably, approximately 50% of all TNBC and PDX-TNBC expressed the three biomarkers. Single erlotinib and palbociclib treatments drastically reduced the in vitro proliferation of cells expressing EGFR and MT4-MMP when compared with control cells. Both TNBC xenografts and PDX expressing MT4-MMP, EGFR, and RB, but not PDX-TNBC with RB loss, were sensitive to erlotinib and palbociclib with an additive effect of combination therapy. Moreover, this combination was efficient in another PDX-TNBC expressing the three biomarkers and resistant to erlotinib alone. CONCLUSIONS: We defined a new association of three biomarkers (MT4-MMP/EGFR/RB) expressed together in 50% of TNBC and demonstrated its usefulness to predict the TNBC response to anti-EGFR and anti-CDK4/6 drugs used in single or combined therapy.

Transcriptome-wide analysis of natural antisense transcripts shows their potential role in breast cancer.

Non-coding RNAs (ncRNA) represent 1/5 of the mammalian transcript number, and 90% of the genome length is transcribed. Many ncRNAs play a role in cancer. Among them, non-coding natural antisense transcripts (ncNAT) are RNA sequences that are complementary and overlapping to those of either protein-coding (PCT) or non-coding transcripts. Several ncNATs were described as regulating protein coding gene expression on the same loci, and they are expected to act more frequently in cis compared to other ncRNAs that commonly function in trans. In this work, 22 breast cancers expressing estrogen receptors and their paired adjacent non-malignant tissues were analyzed by strand-specific RNA sequencing. To highlight ncNATs potentially playing a role in protein coding gene regulations that occur in breast cancer, three different data analysis methods were used: differential expression analysis of ncNATs between tumor and non-malignant tissues, differential correlation analysis of paired ncNAT/PCT between tumor and non-malignant tissues, and ncNAT/PCT read count ratio variation between tumor and non-malignant tissues. Each of these methods yielded lists of ncNAT/PCT pairs that were enriched in survival-associated genes. This work highlights ncNAT lists that display potential to affect the expression of protein-coding genes involved in breast cancer pathology.

MT4-MMP and EGFR expression levels are key biomarkers for breast cancer patient response to chemotherapy and erlotinib.

BACKGROUND: Triple-negative breast cancers (TNBC) are heterogeneous cancers with poor prognosis. We aimed to determine the clinical relevance of membrane type-4 matrix metalloproteinase (MT4-MMP), a membrane type matrix metalloproteinase that interacts with epidermal growth factor receptor (EGFR) overexpressed in >50% of TNBC. METHODS: We conducted a retrospective immunohistochemical analysis on human TNBC samples (n=81) and validated our findings in in vitro and in vivo assays. RESULTS: Membrane type-4 matrix metalloproteinase and EGFR are produced in 72.5% of TNBC samples, whereas those proteins are faintly produced by healthy tissues. Unexpectedly, tumour relapse after chemotherapy was reduced in samples highly positive for MT4-MMP. Mechanistically, this is ascribed to a higher sensitivity of MT4-MMP-producing cells to alkylating or intercalating chemotherapeutic agents, as assessed in vitro. In sharp contrast, MT4-MMP expression did not affect tumour cell sensitivity to paclitaxel that interferes with protease trafficking. Importantly, MT4-MMP expression sensitised cancer cells to erlotinib, a tyrosine kinase EGFR inhibitor. In a pre-clinical model, the growth of MT4-MMP overexpressing xenografts, but not of control ones, was reduced by epirubicin or erlotinib. The combination of suboptimal drug doses blocked drastically the growth of MT4-MMP-producing tumours. CONCLUSIONS: We demonstrate that MT4-MMP defines a sub-population of TNBC sensitive to a combination of DNA-targeting chemotherapeutic agents and anti-EGFR drugs.

Resistance to therapy in estrogen receptor positive and human epidermal growth factor 2 positive breast cancers: progress with latest therapeutic strategies.

In this article, we focus on the subtype of estrogen receptor (ER)-positive, human epidermal growth factor 2 (HER2)-positive breast cancer (BC). Preclinical and clinical data indicate a complex molecular bidirectional crosstalk between the ER and HER2 pathways. This crosstalk probably constitutes one of the key mechanisms of drug resistance in this subclass of BC. Delaying or even reversing drug resistance seems possible by targeting pathways implicated in this crosstalk. High-risk patients currently receive anti-HER2 therapy, chemotherapy and endocrine therapy in the adjuvant setting. In metastatic cases, most patients receive a combination of anti-HER2 therapy and chemotherapy. Only selected patients presenting more indolent disease are candidates for combinations of anti-HER2 therapy and endocrine therapy. However, relative improvements in progression-free survival by chemotherapy-based regimens are usually lower in ER-positive patients than the ER-negative and HER2-positive subgroup. Consequently, new approaches aiming to overcome endocrine therapy resistance by adding targeted therapies to endocrine therapy based regimens are currently explored. In addition, dual blockade of HER2 or the combination of trastuzumab and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOP) inhibitors targeting the downstream pathway are strategies to overcome resistance to trastuzumab. This may lead in the near future to the less frequent use of chemotherapy-based treatment options in ER-positive, HER2-positive BC.

Triple-negative breast cancer: treatment challenges and solutions.

Triple-negative breast cancers (TNBCs) are defined by the absence of estrogen and progesterone receptors and the absence of HER2 overexpression. These cancers represent a heterogeneous breast cancer subtype with a poor prognosis. Few systemic treatment options exist besides the use of chemotherapy (CT). The heterogeneity of the disease has limited the successful development of targeted therapy in unselected patient populations. Currently, there are no approved targeted therapies for TNBC. However, intense research is ongoing to identify specific targets and develop additional and better systemic treatment options. Standard adjuvant and neoadjuvant regimens include anthracyclines, cyclophosphamide, and taxanes. Platinum-based CT has been proposed as another CT option of interest in TNBC. We review the role of this therapy in general, and particularly in patients carrying BRCA germ-line mutations. Available data concerning the role of platinum-based CT in TNBC were acquired primarily in the neoadjuvant setting. The routine use of platinum-based CT is not yet recommended by available guidelines. Many studies have reported the molecular characterization of TNBCs. Several actionable targets have been identified. Novel therapeutic strategies are currently being tested in clinical trials based on promising results observed in preclinical studies. These targets include androgen receptor, EGFR, PARP, FGFR, and the angiogenic pathway. We review the recent data on experimental drugs in this field. We also discuss the recent data concerning immunologic checkpoint inhibitors.

Circulating microRNA-based screening tool for breast cancer.

Circulating microRNAs (miRNAs) are increasingly recognized as powerful biomarkers in several pathologies, including breast cancer. Here, their plasmatic levels were measured to be used as an alternative screening procedure to mammography for breast cancer diagnosis.A plasma miRNA profile was determined by RT-qPCR in a cohort of 378 women. A diagnostic model was designed based on the expression of 8 miRNAs measured first in a profiling cohort composed of 41 primary breast cancers and 45 controls, and further validated in diverse cohorts composed of 108 primary breast cancers, 88 controls, 35 breast cancers in remission, 31 metastatic breast cancers and 30 gynecologic tumors.A receiver operating characteristic curve derived from the 8-miRNA random forest based diagnostic tool exhibited an area under the curve of 0.81. The accuracy of the diagnostic tool remained unchanged considering age and tumor stage. The miRNA signature correctly identified patients with metastatic breast cancer. The use of the classification model on cohorts of patients with breast cancers in remission and with gynecologic cancers yielded prediction distributions similar to that of the control group.Using a multivariate supervised learning method and a set of 8 circulating miRNAs, we designed an accurate, minimally invasive screening tool for breast cancer.

Evaluation of BRCA1-related molecular features and microRNAs as prognostic factors for triple negative breast cancers.

BACKGROUND: The BRCA1 gene plays a key role in triple negative breast cancers (TNBCs), in which its expression can be lost by multiple mechanisms: germinal mutation followed by deletion of the second allele; negative regulation by promoter methylation; or miRNA-mediated silencing. This study aimed to establish a correlation among the BRCA1-related molecular parameters, tumor characteristics and clinical follow-up of patients to find new prognostic factors. METHODS: BRCA1 protein and mRNA expression was quantified in situ in the TNBCs of 69 patients. BRCA1 promoter methylation status was checked, as well as cytokeratin 5/6 expression. Maintenance of expressed BRCA1 protein interaction with BARD1 was quantified, as a marker of BRCA1 functionality, and the tumor expression profiles of 27 microRNAs were determined. RESULTS: miR-548c-5p was emphasized as a new independent prognostic factor in TNBC. A combination of the tumoral expression of miR-548c and three other known prognostic parameters (tumor size, lymph node invasion and CK 5/6 expression status) allowed for relapse prediction by logistic regression with an area under the curve (AUC) = 0.96. BRCA1 mRNA and protein in situ expression, as well as the amount of BRCA1 ligated to BARD1 in the tumor, lacked any associations with patient outcomes, likely due to high intratumoral heterogeneity, and thus could not be used for clinical purposes. CONCLUSIONS: In situ BRCA1-related expression parameters could be used for clinical purposes at the time of diagnosis. In contrast, miR-548c-5p showed a promising potential as a prognostic factor in TNBC.

Chemotherapy options for patients suffering from heavily pretreated metastatic breast cancer.

The identification of additional chemotherapy agents for anthracycline- and taxane-pretreated advanced breast cancer (ABC) is an urgent medical need. Single agent chemotherapy is most times administered because combined therapy is only associated with modest, if any, improvement in median progression-free survival. Randomized trials failed to show overall survival benefit compared with single agent chemotherapy. We hope to modify the natural history of ABC by the consecutive use of treatments with documented activity in heavily pretreated patients. Quality of life remains an important end point as cure is in general not possible. We first review the activity of the approved and the most frequently used agents in heavily pretreated ABC. Thereafter, the potential role and safety profile of etirinotecan pegol is discussed given the results recently released of a Phase III trial comparing this agent to Treatment of Physician's Choice.

EGFR activation and signaling in cancer cells are enhanced by the membrane-bound metalloprotease MT4-MMP.

MT4-MMP (MMP-17) is a glycosylphosphatidyl inositol-anchored matrix metalloprotease expressed on the surface of cancer cells that promotes tumor growth and metastasis. In this report, we identify MT4-MMP as an important driver of cancer cell proliferation through CDK4 activation and retinoblastoma protein inactivation. We also determine a functional link between MT4-MMP and the growth factor receptor EGFR. Mechanistic experiments revealed direct association of MT4-MMP and its positive effects on EGFR phosphorylation in response to TGFα and EGF in cancer cells. Notably, the effects of MT4-MMP on proliferation and EGFR activation did not rely on metalloprotease activity. Clinically, MT4-MMP and EGFR expressions were correlated in human triple-negative breast cancer specimens. Altogether, our results identify MT4-MMP as a positive modifier of EGFR outside-in signaling that acts to cooperatively drive cancer cell proliferation.

Use of mTOR inhibitors in the treatment of breast cancer: an evaluation of factors that influence patient outcomes.

Many systemic treatment options are available for advanced breast cancer, including endocrine therapy, chemotherapy, anti-human epidermal growth factor receptor 2 (HER2) therapy, and other targeted agents. Recently, everolimus, a mammalian target of rapamycin (mTOR) inhibitor, combined with exemestane, an aromatase inhibitor, has been approved in Europe and the USA for patients suffering from estrogen receptor-positive, HER2-negative advanced breast cancer previously treated by a nonsteroidal aromatase inhibitor, based on the results of BOLERO-2 (Breast cancer trials of OraL EveROlimus). This study showed a statistically significant and clinically meaningful improvement in median progression-free survival. Results concerning the impact on overall survival are expected in the near future. This clinically oriented review focuses on the use of mTOR inhibitors in breast cancer. Results reported with first-generation mTOR inhibitors (ridaforolimus, temsirolimus, everolimus) are discussed. The current and potential role of mTOR inhibitors is reported according to breast cancer subtype (estrogen receptor-positive HER2-negative, triple-negative, and HER2-positive ER-positive/negative disease). Everolimus is currently being evaluated in the adjuvant setting in high-risk estrogen receptor-positive, HER2-negative early breast cancer. Continuing mTOR inhibition or alternatively administering other drugs targeting the phosphatidylinositol-3-kinase/protein kinase B-mTOR pathway after progression on treatments including an mTOR inhibitor is under evaluation. Potential biomarkers to select patients showing a more pronounced benefit are reviewed, but we are not currently using these biomarkers in routine practice. Subgroup analysis of BOLERO 2 has shown that the benefit is consistent in all subgroups and that it is impossible to select patients not benefiting from addition of everolimus to exemestane. Side effects and impact on quality of life are other important issues discussed in this review. Second-generation mTOR inhibitors and dual mTOR-phosphatidylinositol-3-kinase inhibitors are currently being evaluated in clinical trials.