The activation of TP53 is well known to exert tumor suppressive effects. We have detected a primate-specific adrenal androgen-mediated tumor suppression system in which circulating DHEAS is converted to DHEA specifically in cells in which TP53 has been inactivated. DHEA is an uncompetitive inhibitor of glucose-6-phosphate dehydrogenase (G6PD), an enzyme indispensable for maintaining reactive oxygen species within limits survivable by the cell. Uncompetitive inhibition is otherwise unknown in natural systems because it becomes irreversible in the presence of high concentrations of substrate and inhibitor. In addition to primate-specific circulating DHEAS, a unique, primate-specific sequence motif that disables an activating regulatory site in the glucose-6-phosphatase (G6PC) promoter was also required to enable function of this previously unrecognized tumor suppression system. In human somatic cells, loss of TP53 thus triggers activation of DHEAS transport proteins and steroid sulfatase, which converts circulating DHEAS into intracellular DHEA, and hexokinase which increases glucose-6-phosphate substrate concentration. The triggering of these enzymes in the TP53-affected cell combines with the primate-specific G6PC promoter sequence motif that enables G6P substrate accumulation, driving uncompetitive inhibition of G6PD to irreversibility and ROS-mediated cell death. By this catastrophic ‘kill switch’ mechanism, TP53 mutations are effectively prevented from initiating tumorigenesis in the somatic cells of humans, the primate with the highest peak levels of circulating DHEAS. TP53 mutations in human tumors therefore represent fossils of kill switch failure resulting from an age-related decline in circulating DHEAS, a potentially reversible artifact of hominid evolution.
Abigail Read and Rachael Natrajan
Breast cancer is known to be a heterogeneous disease driven by a large repertoire of molecular abnormalities, which contribute to its diverse clinical behaviour. Despite the success of targeted therapy approaches for breast cancer patient management, there is still a lack of the molecular understanding of aggressive forms of the disease and clinical management of these patients remains difficult. The advent of high-throughput sequencing technologies has paved the way for a more complete understanding of the molecular make-up of the breast cancer genome. As such, it is becoming apparent that disruption of canonical splicing within breast cancer governs its clinical progression. In this review, we discuss the role of dysregulation of spliceosomal component genes and associated factors in the progression of breast cancer, their role in therapy resistance and the use of quantitative isoform expression as potential prognostic and predictive biomarkers with a particular focus on oestrogen receptor-positive breast cancer.
J Crona, F Beuschlein, K Pacak, and B Skogseid
This review aims to provide clinicians and researchers with a condensed update on the most important studies in the field during 2017. We present the academic output measured by active clinical trials and peer-reviewed published manuscripts. The most important and contributory manuscripts were summarized for each diagnostic entity, with a particular focus on manuscripts that describe translational research that have the potential to improve clinical care. Finally, we highlight the importance of collaborations in adrenal tumor research, which allowed for these recent advances and provide structures for future success in this scientific field.
Claudia Tulotta and Penelope Ottewell
Approximately 75% of patients with late-stage breast cancer will develop bone metastasis. This condition is currently considered incurable and patients’ life expectancy is limited to 2–3 years following diagnosis of bone involvement. Interleukin (IL)-1B is a pro-inflammatory cytokine whose expression in primary tumours has been identified as a potential biomarker for predicting breast cancer patients at increased risk for developing bone metastasis. In this review, we discuss how IL-1B from both the tumour cells and the tumour microenvironment influence growth of primary breast tumours, dissemination into the bone metastatic niche and proliferation into overt metastases. Recent evidence indicates that targeting IL-1B signalling may provide promising new treatments that can hold tumour cells in a dormant state within bone thus preventing formation of overt bone metastases.
Sara Pusceddu, Francesco Barretta, Annalisa Trama, Laura Botta, Massimo Milione, Roberto Buzzoni, Filippo De Braud, Vincenzo Mazzaferro, Ugo Pastorino, Ettore Seregni, Luigi Mariani, Gemma Gatta, Maria Di Bartolomeo, Daniela Femia, Natalie Prinzi, Jorgelina Coppa, Francesco Panzuto, Lorenzo Antonuzzo, Emilio Bajetta, Maria Pia Brizzi, Davide Campana, Laura Catena, Harry Comber, Fiona Dwane, Nicola Fazio, Antongiulio Faggiano, Dario Giuffrida, Kris Henau, Toni Ibrahim, Riccardo Marconcini, Sara Massironi, Maja Primic Žakelj, Francesca Spada, Salvatore Tafuto, Elizabeth Van Eycken, Jan Maaten Van der Zwan, Tina Žagar, Luca Giacomelli, Rosalba Miceli, and NEPscore Working Group
No validated prognostic tool is available for predicting overall survival (OS) of patients with well-differentiated neuroendocrine tumors (WDNETs). This study, conducted in three independent cohorts of patients from five different European countries, aimed to develop and validate a classification prognostic score for OS in patients with stage IV WDNETs. We retrospectively collected data on 1387 patients: (i) patients treated at the Istituto Nazionale Tumori (Milan, Italy; n = 515); (ii) European cohort of rare NET patients included in the European RARECAREnet database (n = 457); (iii) Italian multicentric cohort of pancreatic NET (pNETs) patients treated at 24 Italian institutions (n = 415). The score was developed using data from patients included in cohort (i) (training set); external validation was performed by applying the score to the data of the two independent cohorts (ii) and (iii) evaluating both calibration and discriminative ability (Harrell C statistic). We used data on age, primary tumor site, metastasis (synchronous vs metachronous), Ki-67, functional status and primary surgery to build the score, which was developed for classifying patients into three groups with differential 10-year OS: (I) favorable risk group: 10-year OS ≥70%; (II) intermediate risk group: 30% ≤ 10-year OS < 70%; (III) poor risk group: 10-year OS <30%. The Harrell C statistic was 0.661 in the training set, and 0.626 and 0.601 in the RARECAREnet and Italian multicentric validation sets, respectively. In conclusion, based on the analysis of three ‘field-practice’ cohorts collected in different settings, we defined and validated a prognostic score to classify patients into three groups with different long-term prognoses.
Andrew G Gianoukakis, Corina E Dutcus, Nicolas Batty, Matthew Guo, and Mahadi Baig
We present an updated analysis of lenvatinib in radioiodine-refractory differentiated thyroid cancer (RR-DTC) with new duration of response (DOR) data unavailable for the primary analysis. In this randomized, double-blind, multicenter, placebo-controlled phase 3 study, patients ≥18 years old with measurable, pathologically confirmed RR-DTC with independent radiologic confirmation of disease progression within the previous 13 months were randomized 2:1 to oral lenvatinib 24 mg/day or placebo. The main outcome measures for this analysis are DOR and progression-free survival (PFS). The median DOR for all lenvatinib responders (patients with complete or partial responses; objective response rate: 60.2%; 95% confidence interval (CI) 54.2–66.1) was 30.0 months (95% CI 18.4–36.7) and was generally similar across subgroups. DOR was shorter in patients with greater disease burden and with brain and liver metastases. Updated median PFS was longer in the overall lenvatinib group vs placebo (19.4 vs 3.7 months; hazard ratio (HR) 0.24; 99% CI 0.17–0.35; nominal P < 0.0001). In lenvatinib responders, median PFS was 33.1 months (95% CI 27.8–44.6) vs 7.9 months (95% CI 5.8–10.7) in non-responders. The median DOR of 30.0 months seen with patients who achieved complete or partial responses with lenvatinib (60.2%) demonstrates that lenvatinib responders can have prolonged, durable and clinically meaningful responses. Prolonged PFS (33.1 months) was also observed in these lenvatinib responders.
Yong-Zi Chen, Youngchul Kim, Hatem H Soliman, GuoGuang Ying, and Jae K Lee
ER-negative breast cancer includes most aggressive subtypes of breast cancer such as triple negative (TN) breast cancer. Excluded from hormonal and targeted therapies effectively used for other subtypes of breast cancer, standard chemotherapy is one of the primary treatment options for these patients. However, as ER− patients have shown highly heterogeneous responses to different chemotherapies, it has been difficult to select most beneficial chemotherapy treatments for them. In this study, we have simultaneously developed single drug biomarker models for four standard chemotherapy agents: paclitaxel (T), 5-fluorouracil (F), doxorubicin (A) and cyclophosphamide (C) to predict responses and survival of ER− breast cancer patients treated with combination chemotherapies. We then flexibly combined these individual drug biomarkers for predicting patient outcomes of two independent cohorts of ER− breast cancer patients who were treated with different drug combinations of neoadjuvant chemotherapy. These individual and combined drug biomarker models significantly predicted chemotherapy response for 197 ER− patients in the Hatzis cohort (AUC = 0.637, P = 0.002) and 69 ER− patients in the Hess cohort (AUC = 0.635, P = 0.056). The prediction was also significant for the TN subgroup of both cohorts (AUC = 0.60, 0.72, P = 0.043, 0.009). In survival analysis, our predicted responder patients showed significantly improved survival with a >17 months longer median PFS than the predicted non-responder patients for both ER− and TN subgroups (log-rank test P-value = 0.018 and 0.044). This flexible prediction capability based on single drug biomarkers may allow us to even select new drug combinations most beneficial to individual patients with ER− breast cancer.
Douglas A Gibson, Frances Collins, Fiona L Cousins, Arantza Esnal Zufiaurre, and Philippa T K Saunders
Endometrial cancer (EC) is the most common gynaecological malignancy. Obesity is a major risk factor for EC and is associated with elevated cholesterol. 27-hydroxycholesterol (27HC) is a cholesterol metabolite that functions as an endogenous agonist for Liver X receptor (LXR) and a selective oestrogen receptor modulator (SERM). Exposure to oestrogenic ligands increases risk of developing EC; however, the impact of 27HC on EC is unknown. Samples of stage 1 EC (n = 126) were collected from postmenopausal women undergoing hysterectomy. Expression of LXRs (NR1H3, LXRα; NR1H2, LXRβ) and enzymes required for the synthesis (CYP27A1) or breakdown (CYP7B1) of 27HC were detected in all grades of EC. Cell lines originating from well-, moderate- and poorly-differentiated ECs (Ishikawa, RL95, MFE 280 respectively) were used to assess the impact of 27HC or the LXR agonist GW3965 on proliferation or expression of a luciferase reporter gene under the control of LXR- or ER-dependent promoters (LXRE, ERE). Incubation with 27HC or GW3965 increased transcription via LXRE in Ishikawa, RL95 and MFE 280 cells (P < 0.01). 27HC selectively activated ER-dependent transcription (P < 0.001) in Ishikawa cells and promoted proliferation of both Ishikawa and RL95 cells (P < 0.001). In MFE 280 cells, 27HC did not alter proliferation but selective targeting of LXR with GW3965 significantly reduced cell proliferation (P < 0.0001). These novel results suggest that 27HC can contribute to risk of EC by promoting proliferation of endometrial cancer epithelial cells and highlight LXR as a potential therapeutic target in the treatment of advanced disease.
Sergio Vargas-Salas, José R Martínez, Soledad Urra, José Miguel Domínguez, Natalia Mena, Thomas Uslar, Marcela Lagos, Marcela Henríquez, and Hernán E González
Thyroid cancer is the most frequent endocrine malignancy, and its incidence is increasing. A current limitation of cytological evaluation of thyroid nodules is that 20–25% are reported as indeterminate. Therefore, an important challenge for clinicians is to determine whether an indeterminate nodule is malignant, and should undergo surgery, or benign, and should be recommended to follow-up. The emergence of precision medicine has offered a valuable solution for this problem, with four tests currently available for the molecular diagnosis of indeterminate cytologies. However, efforts to critically analyze the quality of the accumulated evidence are scarce. This systematic review and meta-analysis is aimed to contribute to a better knowledge about the four available molecular tests, their technical characteristics, clinical performance, and ultimately to help clinicians to make better decisions to provide the best care options possible. For this purpose, we address three critical topics: (i) the proper theoretical accuracy, considering the intended clinical use of the test (rule-in vs rule-out) and the impact on clinical decisions; (ii) the quality of the evidence reported for each test (iii) and how accurate and effective have the tests proved to be after their clinical use. Together with the upcoming evidence, this work provides significant and useful information for healthcare system decision-makers to consider the use of molecular testing as a public health need, avoiding unnecessary surgical risks and costs.
Victoria Byrd, Ted Getz, Roshan Padmanabhan, Hans Arora, and Charis Eng
Germline PTEN mutations defining PTEN hamartoma tumor syndrome (PHTS) confer heritable predisposition to breast, endometrial, thyroid and other cancers with known age-related risks, but it remains impossible to predict if any individual will develop cancer. In the general population, gut microbial dysbiosis has been linked to cancer, yet is unclear whether these are associated in PHTS patients. In this pilot study, we aimed to characterize microbial composition of stool, urine, and oral wash from 32 PTEN mutation-positive individuals using 16S rRNA gene sequencing. PCoA revealed clustering of the fecal microbiome by cancer history (P = 0.03, R 2 = 0.04). Fecal samples from PHTS cancer patients had relatively more abundant operational taxonomic units (OTUs) from family Rikenellaceae and unclassified members of Clostridia compared to those from non-cancer patients, whereas families Peptostreptococcaceae, Enterobacteriaceae, and Bifidobacteriaceae represented relatively more abundant OTUs among fecal samples from PHTS non-cancer patients. Functional metagenomic prediction revealed enrichment of the folate biosynthesis, genetic information processing and cell growth and death pathways among fecal samples from PHTS cancer patients compared to non-cancer patients. We found no major shifts in overall diversity and no clustering by cancer history among oral wash or urine samples. Our observations suggest the utility of an expanded study to interrogate gut dysbiosis as a potential cancer risk modifier in PHTS patients.