Recent advances in precision medicine for pancreatic ductal adenocarcinoma

Multicenter Prospective Cohort Study of Neoadjuvant Chemotherapy for Borderline Resectable Pancreatic Cancer (YPB-001)

OBJECTIVES

The present multicenter prospective observational study investigated the effectiveness and safety of neoadjuvant chemotherapy (NAC) for patients with borderline resectable pancreatic cancer (BRPC) and those with RPC contacting major vessels, with respect to a historical control of upfront surgery.

MATERIALS AND METHODS

Patients with BRPC and RPC contacting major vessels were prospectively registered and administered NAC with durations and regimens determined by the corresponding treating physician. Our primary aim was to assess the R0 resection rate, and secondary aim was to evaluate safety, resection rate, time to treatment failure, overall survival, and response rate.

RESULTS

Fifty of 52 enrolled patients were analyzed; 2 with serious comorbidities died during treatment. Thirty-one patients underwent resection, with R0 resection being achieved in 26 (52% of total and 84% of all resected cases). Univariate and multivariate analyses indicated age (≥75 years) as the only independent predictor of nonresection. Median progression-free survival and median survival time were longer in the prospective cohort than in the historical cohort.

CONCLUSIONS

Overall, NAC for BRPC in real-world setting might yield R0 resection rates similar to those reported in previous clinical studies. Development of safe regimens and management strategies that can maintain treatment intensity in geriatric patients is warranted.

Treatment of pancreatic adenocarcinoma in relation to survival in the U.S. Military Health System

BACKGROUND

Pancreatic cancer has a high case fatality and relatively short survival after diagnosis. Treatment is paramount to improving survival, but studies on the effects of standard treatment by surgery or chemotherapy on survival in U.S. healthcare settings is limited. Further, variability in access to care may impact treatment and outcomes for patients. We aimed to assess the relationship between standard treatment(s) and survival of pancreatic adenocarcinoma in a population with access to comprehensive healthcare.

METHODS

We used the Military Cancer Epidemiology (MilCanEpi) database, which includes data from the Department of Defense cancer registry and medical encounter data from the Military Health System (MHS), to study a cohort of 1408 men and women who were diagnosed with pancreatic adenocarcinoma between 1998 and 2014. Treatment with surgery or chemotherapy in relation to overall survival was examined in multivariable time-dependent Cox regression models.

RESULTS

Overall, 75 % of 441 patients with early-stage and 51 % of 967 patients with late-stage pancreatic adenocarcinoma received treatment. In early-stage disease, surgery alone or surgery with chemotherapy were both associated with statistically significant 52 % reduced risks of death, but chemotherapy alone was not. In late-stage disease, surgery alone, chemotherapy alone, or both surgery and chemotherapy significantly reduced the risk of death by 42 %, 25 %, and 52 %, respectively.

CONCLUSIONS

Our findings from the MHS demonstrate improved survival after treatment with surgery or surgery with chemotherapy for early- or late-stage pancreatic cancer and after chemotherapy for late-stage pancreatic cancer. In the era of immunotherapy and personalized medicine, further research on treatment and survival of pancreatic cancer in observational settings is needed.

Copy Number Variations in Pancreatic Cancer: From Biological Significance to Clinical Utility

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer, characterized by high tumor heterogeneity and a poor prognosis. Inter- and intra-tumoral heterogeneity in PDAC is a major obstacle to effective PDAC treatment; therefore, it is highly desirable to explore the tumor heterogeneity and underlying mechanisms for the improvement of PDAC prognosis. Gene copy number variations (CNVs) are increasingly recognized as a common and heritable source of inter-individual variation in genomic sequence. In this review, we outline the origin, main characteristics, and pathological aspects of CNVs. We then describe the occurrence of CNVs in PDAC, including those that have been clearly shown to have a pathogenic role, and further highlight some key examples of their involvement in tumor development and progression. The ability to efficiently identify and analyze CNVs in tumor samples is important to support translational research and foster precision oncology, as copy number variants can be utilized to guide clinical decisions. We provide insights into understanding the CNV landscapes and the role of both somatic and germline CNVs in PDAC, which could lead to significant advances in diagnosis, prognosis, and treatment. Although there has been significant progress in this field, understanding the full contribution of CNVs to the genetic basis of PDAC will require further research, with more accurate CNV assays such as single-cell techniques and larger cohorts than have been performed to date.

A pancreatic adenocarcinoma mimicking hepatoid carcinoma of uncertain histogenesis: A case report and literature review

In rare cases, metastatic adenocarcinomas of different origin may exhibit the features of hepatoid carcinoma (HC), a rare malignant epithelial tumor, most commonly occurring in the ovaries and stomach, as well as in the pancreas and biliary ducts. A case of a 72-year-old female patient who developed a highly aggressive, poorly differentiated pancreatic ductal adenocarcinoma with peritoneal carcinomatosis, demonstrating hepatoid differentiation upon conventional hematoxylin and eosin staining is reported in the present study. The patient presented with severe abdominal pain, and the radiological investigations performed revealed ovarian and hepatic tumor masses and peritoneal lesions, which were surgically removed. The gross examination of the peritoneum and omentum revealed multiple solid, firm, grey-white nodules, diffusely infiltrating the adipose tissue. The microscopic examination revealed a malignant epithelial proliferation, composed of polygonal cells with abundant eosinophilic cytoplasm and irregular, pleomorphic nuclei. Certain cells presented with intracytoplasmic mucus inclusions, raising suspicion of a HC with an uncertain histogenesis. Immunohistochemical staining was performed, and the tumor cells were found to be positive for cytokeratin (CK)7, CK18 and mucin 5AC, whereas negative staining for CK20, caudal-type homeobox transcription factor 2, α-fetoprotein, paired box gene 8, GATA-binding protein 3 and Wilms tumor 1 were documented. Thus, the diagnosis of metastatic pancreatic adenocarcinoma was established. The main aim of the present study was to provide further knowledge concerning poorly differentiated metastatic adenocarcinoma resembling HC, emphasizing the histopathological and immunohistochemical features of these malignant lesions and raising awareness of the diagnostic difficulties that may arise, as well as the importance of the use immunohistochemistry in differentiating carcinomas of uncertain histogenesis.

Pancreatic ductal adenocarcinoma arising from the pancreatic parenchyma compressed by a huge pancreatic lipoma: a case report

BACKGROUND

Pancreatic lipomas (PLs) arising from the adipose tissue in the pancreatic parenchyma are rare among pancreatic tumors. Coexisting pancreatic ductal adenocarcinoma (PDAC) and PLs have not been previously reported. Herein, we report a case of PDAC arising from the pancreatic parenchyma with chronic pancreatitis compressed by a large PL.

CASE PRESENTATION

The patient was a 69-year-old male. He had been diagnosed with a PL using computed tomography (CT) 12 years previously. The tumor had been slowly growing and was followed up carefully because of the possibility of well-differentiated liposarcoma. During follow-up, laboratory data revealed liver damage and slightly elevated levels of inflammatory markers. Contrast-enhanced CT revealed the previously diagnosed 12 cm pancreatic head tumor and an irregular isodensity mass at the upper margin of the tumor that invaded and obstructed the distal common bile duct. Magnetic resonance cholangiopancreatography demonstrated no specific findings in the main pancreatic duct. Based on these imaging findings, the patient underwent endoscopic retrograde biliary drainage and bile duct brushing cytology, which revealed indeterminate findings. The differential diagnosis of the tumor at that time was as follows: (1) pancreatic liposarcoma (focal change from well-differentiated to dedifferentiated, not lipoma), (2) distal cholangiocarcinoma, and (3) pancreatic cancer. After the cholangitis improved, a pancreatoduodenectomy was performed. Histologically, hematoxylin-eosin staining revealed moderately differentiated PDAC compressed by proliferating adipose tissue. The adipose lesion showed homogeneous adipose tissue with no evidence of sarcoma, which led to a diagnosis of lipoma. Additionally, extensive fibrosis of the pancreatic parenchyma and atrophy of the acinar cells around the lipoma was suggestive of chronic pancreatitis. The pathological diagnosis was PDAC (pT2N0M0 pStage Ib) with chronic pancreatitis and PL. The postoperative course was uneventful, and the patient was discharged on the 15th day after surgery. The patient received adjuvant chemotherapy and has remained recurrence-free for more than 6 months.

CONCLUSIONS

PL may be associated with the development of PDAC in the surrounding inflammatory microenvironment of chronic pancreatitis. In cases of growing lipomas, careful radiologic surveillance may be needed not only for the possibility of liposarcoma but also for the coincidental occurrence of PDAC.

Three-dimensional analysis of human pancreatic cancer specimens by phase-contrast based X-ray tomography - the next dimension of diagnosis

BACKGROUND

The worldwide increase of pancreatic ductal adenocarcinoma (PDAC), which still has one of the lowest survival rates, requires novel imaging tools to improve early detection and to refine diagnosis. Therefore, the aim of this study was to assess the feasibility of propagation-based phase-contrast X-ray computed tomography of already paraffin-embedded and unlabeled human pancreatic tumor tissue to achieve a detailed three-dimensional (3D) view of the tumor sample in its entirety.

METHODS

Punch biopsies of areas of particular interest were taken from paraffin blocks after initial histological analysis of hematoxylin and eosin stained tumor sections. To cover the entire 3.5 mm diameter of the punch biopsy, nine individual tomograms with overlapping regions were acquired in a synchrotron parallel beam configuration and stitched together after data reconstruction. Due to the intrinsic contrast based on electron density differences of tissue components and a voxel size of 1.3 μm achieved PDAC and its precursors were clearly identified.

RESULTS

Characteristic tissue structures for PDAC and its precursors, such as dilated pancreatic ducts, altered ductal epithelium, diffuse immune cell infiltrations, increased occurrence of tumor stroma and perineural invasion were clearly identified. Certain structures of interest were visualized in three dimensions throughout the tissue punch. Pancreatic duct ectasia of different caliber and atypical shape as well as perineural infiltration could be contiguously traced by viewing serial tomographic slices and by applying semi-automatic segmentation. Histological validation of corresponding sections confirmed the former identified PDAC features.

CONCLUSION

In conclusion, virtual 3D histology via phase-contrast X-ray tomography visualizes diagnostically relevant tissue structures of PDAC in their entirety, preserving tissue integrity in label-free, paraffin embedded tissue biopsies. In the future, this will not only enable a more comprehensive diagnosis but also a possible identification of new 3D imaging tumor markers.

Hyperglycaemia induces metabolic reprogramming into a glycolytic phenotype and promotes epithelial-mesenchymal transitions via YAP/TAZ-Hedgehog signalling axis in pancreatic cancer

BACKGROUND

Hyperglycaemia is a well-known initial symptom in patients with pancreatic ductal adenocarcinoma (PDAC). Metabolic reprogramming in cancer, described as the Warburg effect, can induce epithelial-mesenchymal transition (EMT).

METHODS

The biological impact of hyperglycaemia on malignant behaviour in PDAC was examined by in vitro and in vivo experiments.

RESULTS

Hyperglycaemia promoted EMT by inducing metabolic reprogramming into a glycolytic phenotype via yes-associated protein (YAP)/PDZ-binding motif (TAZ) overexpression, accompanied by GLUT1 overexpression and enhanced phosphorylation Akt in PDAC. In addition, hyperglycaemia enhanced chemoresistance by upregulating ABCB1 expression and triggered PDAC switch into pure basal-like subtype with activated Hedgehog pathway (GLI1 high, GATA6 low expression) through YAP/TAZ overexpression. PDAC is characterised by abundant stroma that harbours tumour-promoting properties and chemoresistance. Hyperglycaemia promotes the production of collagen fibre-related proteins (fibronectin, fibroblast activation protein, COL1A1 and COL11A1) by stimulating YAP/TAZ expression in cancer-associated fibroblasts (CAFs). Knockdown of YAP and/or TAZ or treatment with YAP/TAZ inhibitor (K975) abolished EMT, chemoresistance and a favourable tumour microenvironment even under hyperglycemic conditions in vitro and in vivo.

CONCLUSION

Hyperglycaemia induces metabolic reprogramming into glycolytic phenotype and promotes EMT via YAP/TAZ-Hedgehog signalling axis, and YAP/TAZ could be a novel therapeutic target in PDAC.

Durable effect of imatinib and metronomic chemotherapy with capecitabine in pancreatic carcinoma

Background

Pancreatic ductal carcinoma (PDC) is a challenging diagnosis with a particularly poor prognosis, even after curative surgery (median survival: <30 months). The prognosis of borderline resectable pancreatic cancer (BR-PDC) is even worse. We describe a patient with BR-PDC who achieved stable disease with metronomic chemotherapy after refusing surgery.

Case presentation

A 75-year-old woman was presented with jaundice and epigastric pain. Imaging confirmed a mass in the pancreatic head encasing the superior mesenteric vein, with obstruction of the pancreatic and bile ducts. After stenting to relieve the obstruction, Fine needle aspiration (FNA) confirmed the diagnosis of PDC. The patient refused surgery and radiation therapy but agreed for chemotherapy. After the second cycle of mFOLFIRINOX - complicated by febrile neutropenia - she refused further IV therapy. Genomic profiling revealed KIT amplification. Therefore, she was started on imatinib with dramatic improvement both clinically and biochemically reflected in carbohydrate antigen 19-9 drop. However, that response was short-lived at 3 months. Therefore, capecitabine was added at a low dose of 1 g bid on an alternate weekly basis. The patient did well and she is currently alive with a stable disease as of 2 years after diagnosis.

Conclusion

Metronomic chemotherapy, especially capecitabine added to the targeted therapy, imatinib, is a potentially useful treatment for PDC where no other options are available, especially those harbouring no mutation in the dominant four genes. Indeed, the absence of mutation with KIT amplification could be a potential marker for improved outcomes with targeted and metronomic therapy, which deserves further evaluation in a clinical trial setting.

Circulating tumor DNA: toward evolving the clinical paradigm of pancreatic ductal adenocarcinoma

Over a decade of sequencing-based genomics research has unveiled a diverse somatic mutation landscape across patients with pancreatic ductal adenocarcinoma (PDAC), and the identification of druggable mutations has aligned with the development of novel targeted therapeutics. However, despite these advances, direct translation of years of PDAC genomics research into the clinical care of patients remains a critical and unmet need. Technologies that enabled the initial mapping of the PDAC mutation landscape, namely whole-genome and transcriptome sequencing, remain overly expensive in terms of both time and financial resources. Consequentially, dependence on these technologies to identify the relatively small subset of patients with actionable PDAC alterations has greatly impeded enrollment for clinical trials testing novel targeted therapies. Liquid biopsy tumor profiling using circulating tumor DNA (ctDNA) generates new opportunities by overcoming these challenges while further addressing issues particularly relevant to PDAC, namely, difficulty of obtaining tumor tissue via fine-needle biopsy and the need for faster turnaround time due to rapid disease progression. Meanwhile, ctDNA-based approaches for tracking disease kinetics with respect to surgical and therapeutic interventions offer a means to elevate the current clinical management of PDAC toward higher granularity and accuracy. This review provides a clinically focused summary of ctDNA advances, limitations, and opportunities in PDAC and postulates ctDNA sequencing technology as a catalyst for evolving the clinical decision-making paradigm of this disease.

Thrombospondin-1 overexpression stimulates loss of Smad4 and accelerates malignant behavior via TGF-β signal activation in pancreatic ductal adenocarcinoma

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma and cancer-associated fibroblasts (CAFs) provide a favorable tumor microenvironment. Smad4 is known as tumor suppressor in several types of cancers including PDAC, and loss of Smad4 triggers accelerated cell invasiveness and metastatic potential. The thrombospondin-1 (TSP-1) can act as a major activator of latent transforming growth factor-β (TGF-β) in vivo. However, the roles of TSP-1 and the mediator of Smad4 loss and TGF-β signal activation during PDAC progression have not yet been addressed. The aim is to elucidate the biological role of TSP-1 in PDAC progression.

METHODS AND RESULTS

High substrate stiffness stimulated TSP-1 expression in CAFs, and TSP-1 knockdown inhibited cell proliferation with suppressed profibrogenic and activated stroma-related gene expressions in CAFs. Paracrine TSP-1 treatment for PDAC cells promoted cell proliferation and epithelial mesenchymal transition (EMT) with activated TGF-β signals such as phosphorylated Akt and Smad2/3 expressions. Surprisingly, knockdown of DPC4 (Smad4 gene) induced TSP-1 overexpression with TGF-β signal activation in PDAC cells. Interestingly, TSP-1 overexpression also induced downregulation of Smad4 expression and enhanced cell proliferation in vitro and in vivo. Treatment with LSKL peptide, which antagonizes TSP-1-mediated latent TGF-β activation, attenuated cell proliferation, migration and chemoresistance with enhanced apoptosis in PDAC cells.

CONCLUSIONS

TSP-1 derived from CAFs stimulates loss of Smad4 expression in cancer cells and accelerates malignant behavior by TGF-β signal activation in PDAC. TSP-1 could be a novel therapeutic target, not only for CAFs in stiff stroma, but also for cancer cells in the PDAC microenvironment.

Mechanisms of PDAC subtype heterogeneity and therapy response

Pancreatic ductal adenocarcinoma (PDAC) is clinically challenging due to late diagnosis and resistance to therapy. Two major PDAC subtypes have been defined based on malignant epithelial cell gene expression profiles; the basal-like/squamous subtype is associated with a worse prognosis and therapeutic resistance as opposed to the classical subtype. Subtype specification is not binary, consistent with plasticity of malignant cell phenotype. PDAC heterogeneity and plasticity reflect partly malignant cell-intrinsic transcriptional and epigenetic regulation. However, the stromal and immune compartments of the tumor microenvironment (TME) also determine disease progression and therapy response. It is evident that integration of intrinsic and extrinsic factors can dictate subtype heterogeneity, and thus, delineating the pathways involved can help to reprogram PDAC towards a classical/druggable subtype.

Determination of a DNA repair-related gene signature with potential implications for prognosis and therapeutic response in pancreatic adenocarcinoma

Background

Pancreatic adenocarcinoma (PAAD) is one of the leading causes of cancer death worldwide. Alterations in DNA repair-related genes (DRGs) are observed in a variety of cancers and have been shown to affect the development and treatment of cancers. The aim of this study was to develop a DRG-related signature for predicting prognosis and therapeutic response in PAAD.

Methods

We constructed a DRG signature using least absolute shrinkage and selection operator (LASSO) Cox regression analysis in the TCGA training set. GEO datasets were used as the validation set. A predictive nomogram was constructed based on multivariate Cox regression. Calibration curve and decision curve analysis (DCA) were applied to validate the performance of the nomogram. The CIBERSORT and ssGSEA algorithms were utilized to explore the relationship between the prognostic signature and immune cell infiltration. The pRRophetic algorithm was used to estimate sensitivity to chemotherapeutic agents. The CellMiner database and PAAD cell lines were used to investigate the relationship between DRG expression and therapeutic response.

Results

We developed a DRG signature consisting of three DRGs (RECQL, POLQ, and RAD17) that can predict prognosis in PAAD patients. A prognostic nomogram combining the risk score and clinical factors was developed for prognostic prediction. The DCA curve and the calibration curve demonstrated that the nomogram has a higher net benefit than the risk score and TNM staging system. Immune infiltration analysis demonstrated that the risk score was positively correlated with the proportions of activated NK cells and monocytes. Drug sensitivity analysis indicated that the signature has potential predictive value for chemotherapy. Analyses utilizing the CellMiner database showed that RAD17 expression is correlated with oxaliplatin. The dynamic changes in three DRGs in response to oxaliplatin were examined by RT-qPCR, and the results show that RAD17 is upregulated in response to oxaliplatin in PAAD cell lines.

Conclusion

We constructed and validated a novel DRG signature for prediction of the prognosis and drug sensitivity of patients with PAAD. Our study provides a theoretical basis for further unraveling the molecular pathogenesis of PAAD and helps clinicians tailor systemic therapies within the framework of individualized treatment.

Genetic analysis of Japanese patients with small bowel adenocarcinoma using next-generation sequencing

BACKGROUND

Small bowel adenocarcinomas (SBAs) are rare and there is little comprehensive data on SBA genomic alterations for Asian patients. This study aimed to profile genomic alterations of SBA in Japanese patients using targeted next-generation sequencing (NGS).

METHODS

We examined 22 surgical resections from patients with primary SBA. SBA genomic alterations were analyzed by NGS. Mismatch repair (MMR) status was determined by immunohistochemical analysis. Mucin phenotypes were classified as gastric (G), intestinal (I), gastrointestinal (GI), and null (N) types on MUC2, MUC5AC, MUC6, and CD10 immunostaining.

RESULTS

The most common genomic alterations found in SBA tumors were TP53 (n = 16), followed by KRAS (n = 6), APC (n = 5), PIK3CA (n = 4), CTNNB1 (n = 3), KIT (n = 2), BRAF (n = 2), CDKN2A (n = 2), and PTEN (n = 2). Deficient MMR tumors were observed in 6 out of 22 patients. Tumor mucin phenotypes included 2 in G-type, 12 in I-type, 3 in GI-type, and 5 in N-type. APC and CTNNB1 mutations were not found in G-type and GI-type tumors. KRAS mutations were found in all tumor types except for G-type tumors. TP53 mutations were found in all tumor types. Although no single gene mutation was associated with overall survival (OS), we found that KRAS mutations were associated with significant worse OS in patients with proficient MMR tumors.

CONCLUSIONS

SBA genomic alterations in Japanese patients do not differ significantly from those reports in Western countries. Tumor localization, mucin phenotype, and MMR status all appear to impact SBA gene mutations.

Pancreatic Cancer and Cellular Senescence: Tumor Microenvironment under the Spotlight

Pancreatic ductal adenocarcinoma (PDAC) has one of the most dismal prognoses of all cancers due to its late manifestation and resistance to current therapies. Accumulating evidence has suggested that the malignant behavior of this cancer is mainly influenced by the associated strongly immunosuppressive, desmoplastic microenvironment and by the relatively low mutational burden. PDAC develops and progresses through a multi-step process. Early in tumorigenesis, cancer cells must evade the effects of cellular senescence, which slows proliferation and promotes the immune-mediated elimination of pre-malignant cells. The role of senescence as a tumor suppressor has been well-established; however, recent evidence has revealed novel pro-tumorigenic paracrine functions of senescent cells towards their microenvironment. Understanding the interactions between tumors and their microenvironment is a growing research field, with evidence having been provided that non-tumoral cells composing the tumor microenvironment (TME) influence tumor proliferation, metabolism, cell death, and therapeutic resistance. Simultaneously, cancer cells shape a tumor-supportive and immunosuppressive environment, influencing both non-tumoral neighboring and distant cells. The overall intention of this review is to provide an overview of the interplay that occurs between senescent and non-senescent cell types and to describe how such interplay may have an impact on PDAC progression. Specifically, the effects and the molecular changes occurring in non-cancerous cells during senescence, and how these may contribute to a tumor-permissive microenvironment, will be discussed. Finally, senescence targeting strategies will be briefly introduced, highlighting their potential in the treatment of PDAC.

Biological Significance of YAP/TAZ in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal types of cancer. Despite major advances in defining the molecular mutations driving PDAC, this disease remains universally lethal with an overall 5-year survival rate of only about 7–8%. Genetic alterations in PDAC are exemplified by four critical genes (KRAS, TP53, CDKN2A, and SMAD4) that are frequently mutated. Among these, KRAS mutation ranges from 88% to 100% in several studies. Hippo signaling is an evolutionarily conserved network that plays a key role in normal organ development and tissue regeneration. Its core consists of the serine/threonine kinases mammalian sterile 20-like kinase 1 and 2 (MST1/2) and large tumor suppressor 1 and 2. Interestingly, pancreas-specific MST1/2 double knockout mice have been reported to display a decreased pancreas mass. Many of the genes involved in the Hippo signaling pathway are recognized as tumor suppressors, while the Hippo transducers Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) are identified as oncogenes. By dephosphorylation, YAP and TAZ accumulate in the nucleus and interact with transcription factors such as TEA domain transcription factor-1, 2, 3, and 4. Dysregulation of Hippo signaling and activation of YAP/TAZ have been recognized in a variety of human solid cancers, including PDAC. Recent studies have elucidated that YAP/TAZ play a crucial role in the induction of acinar-to-ductal metaplasia, an initial step in the progression to PDAC, in genetically engineered mouse models. YAP and TAZ also play a key role in the development of PDAC by both KRAS-dependent and KRAS-independent bypass mechanisms. YAP/TAZ have become extensively studied in PDAC and their biological importance during the development and progression of PDAC has been uncovered. In this review, we summarize the biological significance of a dysregulated Hippo signaling pathway or activated YAP/TAZ in PDAC and propose a role for YAP/TAZ as a therapeutic target.

Role of the BMP6 protein in breast cancer and other types of cancer

The BMP6 protein (Bone Morphogenetic Protein 6) is part of the superfamily of transforming growth factor-beta (TGF-β) ligands, participates in iron homeostasis, inhibits invasion by increasing adhesions and cell-cell type interactions and induces angiogenesis directly on vascular endothelial cells. BMP6 is coded by a tumor suppressor gene whose subexpression is related to the development and cancer progression; during neoplastic processes, methylation is the main mechanism by which gene silencing occurs. This work presents a review on the role of BMP6 protein in breast cancer (BC) and other types of cancer. The studies carried out to date suggest the participation of the BMP6 protein in the epithelial-mesenchymal transition (EMT) phenotype, cell growth and proliferation; however, these processes are affected in a variable way in the different types of cancer, the methylated CpG sites in BMP6 gene promoter, as well as the interaction with other proteins could be the cause of such variation.