Peritumoral fibroblast SPARC expression and patient outcome with resectable pancreatic adenocarcinoma

Nanovectors for anti-cancer drug delivery in the treatment of advanced pancreatic adenocarcinoma

Liposome, albumin and polymer polyethylene glycol are nanovector formulations successfully developed for anti-cancer drug delivery. There are significant differences in pharmacokinetics, efficacy and toxicity between pre- and post-nanovector modification. The alteration in clinical pharmacology is instrumental for the future development of nanovector-based anticancer therapeutics. We have reviewed the results of clinical studies and translational research in nanovector-based anti-cancer therapeutics in advanced pancreatic adenocarcinoma, including nanoparticle albumin-bound paclitaxel and nanoliposomal irinotecan. Furthermore, we have appraised the ongoing studies incorporating novel agents with nanomedicines in the treatment of pancreatic adenocarcinoma.

Orchestrating the Tumor Microenvironment to Improve Survival for Patients With Pancreatic Cancer: Normalization, Not Destruction

Pancreatic cancer is the fourth leading cause of cancer death in the United States. The microenvironment of pancreatic cancer could be one of the "perfect storms" that support the growth of a cancer. Indeed, pancreatic cancer may be the poster child of a problem with the microenvironment. In this article, we review the rationale and attempts to date on modifying or targeting structural proteins in the microenvironment including hyaluronan (HA) (in primary and metastases), collagen, and SPARC (secreted protein, acidic, and rich in cysteine). Indeed, working in this area has produced a regimen that improves survival for patients with advanced pancreatic cancer (nab-paclitaxel + gemcitabine). In addition, in initial clinical trials, PEGylated hyaluronidase appears promising. We also review a new approach that is different than targeting/destroying the microenvironment and that is orchestrating, reengineering, reprogramming, or normalizing the microenvironment (including normalizing structural proteins, normalizing an immunologically tumor-friendly environment to a less friendly environment, reversing epithelial-to-mesenchymal transition, and so on). We believe this will be most effectively done by agents that have global effects on transcription. There is initial evidence that this can be done by agents such as vitamin D derivatives and other new agents. There is no doubt these opportunities can now be tried in the clinic with hopefully beneficial effects.

Targeting inflammation in pancreatic cancer: Clinical translation

Preclinical modelling studies are beginning to aid development of therapies targeted against key regulators of pancreatic cancer progression. Pancreatic cancer is an aggressive, stromally-rich tumor, from which few people survive. Within the tumor microenvironment cellular and extracellular components exist, shielding tumor cells from immune cell clearance, and chemotherapy, enhancing progression of the disease. The cellular component of this microenvironment consists mainly of stellate cells and inflammatory cells. New findings suggest that manipulation of the cellular component of the tumor microenvironment is possible to promote immune cell killing of tumor cells. Here we explore possible immunogenic therapeutic strategies. Additionally extracellular stromal elements play a key role in protecting tumor cells from chemotherapies targeted at the pancreas. We describe the experimental findings and the pitfalls associated with translation of stromally targeted therapies to clinical trial. Finally, we discuss the key inflammatory signal transducers activated subsequent to driver mutations in oncogenic Kras in pancreatic cancer. We present the preclinical findings that have led to successful early trials of STAT3 inhibitors in pancreatic adenocarcinoma.

Molecular therapeutics in pancreas cancer

The emergence of the "precision-medicine" paradigm in oncology has ushered in tremendous improvements in patient outcomes in a wide variety of malignancies. However, pancreas ductal adenocarcinoma (PDAC) has remained an obstinate challenge to the oncology community and continues to be associated with a dismal prognosis with 5-year survival rates consistently less than 5%. Cytotoxic chemotherapy with gemcitabine-based regimens has been the cornerstone of treatment in PDAC especially because most patients present with inoperable disease. But in recent years remarkable basic science research has improved our understanding of the molecular and genetic basis of PDAC. Whole genomic analysis has exemplified the genetic heterogeneity of pancreas cancer and has led to ingenious efforts to target oncogenes and their downstream signaling cascades. Novel stromal depletion strategies have been devised based on our enhanced recognition of the complex architecture of the tumor stroma and the various mechanisms in the tumor microenvironment that sustain tumorigenesis. Immunotherapy using vaccines and immune checkpoint inhibitors has also risen to the forefront of therapeutic strategies against PDAC. Furthermore, adoptive T cell transfer and strategies to target epigenetic regulators are being explored with enthusiasm. This review will focus on the recent advances in molecularly targeted therapies in PDAC and offer future perspectives to tackle this lethal disease.

Modifying the tumor microenvironment using nanoparticle therapeutics

Treatment of cancer has come a long way from the initial 'radical surgeries' to the multimodality treatments. For the major part of the last century, cancer was considered as a monocellular disorder, and treatment strategies were designed according to that hypothesis. However, the mortality rate from cancer continued to be high and a comprehensive treatment remained elusive. Recent progress in research has demonstrated that tumors are a complex network of neoplastic and non-neoplastic cells. The non-neoplastic cells, which are collectively called stroma, assist in tumor survival and progression. It has been shown that disrupting the tumor-stromal balance leads to significant effects on the tumor survival, and effective treatment can be achieved by targeting one or more of the stromal components. In this review, we summarize the roles of various stromal components in promoting tumor progression, and discuss innovative nanoparticle-mediated drug targeting strategies for stromal depletion and the subsequent effects on the tumors. Perspectives and the future directions are also provided. WIREs Nanomed Nanobiotechnol 2016, 8:891-908. doi: 10.1002/wnan.1406 For further resources related to this article, please visit the WIREs website.

The role of SPARC expression in pancreatic cancer progression and patient survival

BACKGROUND

Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein that has been implicated in tumor-stroma interactions in pancreatic cancer. Here we evaluated the expression of SPARC during the progression of pancreatic cancer and its correlation with survival following curative intent surgery.

METHODS

The expression profile of SPARC was investigated in normal pancreas, invasive adenocarcinoma, and lymph node metastasis by immunohistochemistry. Kaplan-Meier and multivariate Cox regression were used to assess for mortality risk.

RESULTS

None (0%) of 10 normal pancreata, 68 (77%) of 88 primary tumors, and 28 (67%) of 42 lymph node metastases were labeled with the SPARC antibody used in this study. SPARC was expressed exclusively in stromal cells. The survival of patients with high stromal SPARC expression was significantly worse than that of the patients with low stromal SPARC expression (11.5 vs 25.3 months; p = 0.020). Multivariate analysis showed that stromal SPARC expression (hazard ratio (HR) 2.12; p = 0.012), tumor location (body/tail) (HR 2.95; p = 0.003), and adjuvant chemotherapy (HR 0.55; p = 0.018) were significant independent risk factors.

CONCLUSION

This study describes the pattern of SPARC expression in pancreatic neoplastic progression and supports the role of stromal SPARC expression as a prognostic factor and target for directed therapy.

Key players in pancreatic cancer-stroma interaction: Cancer-associated fibroblasts, endothelial and inflammatory cells

Pancreatic cancer (PC) is the most aggressive type of common cancers, and in 2014, nearly 40000 patients died from the disease in the United States. Pancreatic ductal adenocarcinoma, which accounts for the majority of PC cases, is characterized by an intense stromal desmoplastic reaction surrounding the cancer cells. Cancer-associated fibroblasts (CAFs) are the main effector cells in the desmoplastic reaction, and pancreatic stellate cells are the most important source of CAFs. However, other important components of the PC stroma are inflammatory cells and endothelial cells. The aim of this review is to describe the complex interplay between PC cells and the cellular and non-cellular components of the tumour stroma. Published data have indicated that the desmoplastic stroma protects PC cells against chemotherapy and radiation therapy and that it might promote the proliferation and migration of PC cells. However, in animal studies, experimental depletion of the desmoplastic stroma and CAFs has led to more aggressive cancers. Hence, the precise role of the tumour stroma in PC remains to be elucidated. However, it is likely that a context-dependent therapeutic modification, rather than pure depletion, of the PC stroma holds potential for the development of new treatment strategies for PC patients.

Prognostic and predictive markers in pancreatic adenocarcinoma

Pancreatic ductal adenocarcinoma is characterized by a poor prognosis and a low median survival, despite improvements observed for many other solid tumours. Intensive research efforts have been undertaken during the last decades to discover new prognostic and treatment predictive biomarkers for pancreatic ductal adenocarcinoma. The mainstay of medical treatment for the disease has been the well-tolerated nucleoside analogue, gemcitabine. The only targeted agent currently used in pancreatic ductal adenocarcinoma patients is the epithelial growth factor receptor inhibitor erlotinib in combination with gemcitabine. Recently, treatment regimens such as a combination of fluorouracil-leucovorin-irinotecan-oxaliplatin (FOLFIRINOX) and the combination of nab-paclitaxel with gemcitabine have been introduced for metastatic pancreatic ductal adenocarcinoma. Although these treatment regimens significantly improve survival of patients, there are no good predictive biomarkers available that can be used to identify who would benefit most from them. Therefore, the search for predictive biomarkers that would facilitate personalization of chemotherapy is highly relevant.

Nab-Paclitaxel Plus S-1 Shows Increased Antitumor Activity in Patient-Derived Pancreatic Cancer Xenograft Mouse Models

OBJECTIVES

To investigate the antitumor activity of nanoparticle albumin-bound paclitaxel (nab-paclitaxel) plus S-1 in patient-derived pancreatic cancer xenograft mouse models and to explore biomarkers that could predict drug efficacy.

METHODS

Ten patient-derived xenograft models were established. The third-generation tumor-bearing mice were randomized into 4 treatment groups: (1) control; (2) S-1; (3) nab-paclitaxel; (4) S-1 plus nab-paclitaxel. Resected tumors were tested by immunohistochemistry for the expression of thymidylate synthase, orotate phosphoribosyltransferase (OPRT), dihydropyrimidine dehydrogenase (DPD), secreted protein that is acidic and rich in cysteine, human epidermal growth factor receptor 2 (HER2), collagen-1, and CD31.

RESULTS

Tumor growth inhibition of the S-1 group, nab-paclitaxel group, and combination group was 69.52%, 86.63%, 103.56%, respectively (P < 0.05). The efficacy of S-1 is better in thymidylate synthase-negative, OPRT-positive, and DPD-negative tumors. The efficacy of nab-paclitaxel is better in HER2-positive tumors. Collagen-1 was decreased and CD31 was increased in tumors treated with nab-paclitaxel and S-1 plus nab-paclitaxel compared with control or S-1.

CONCLUSIONS

This preclinical study showed that S-1 plus nab-paclitaxel exerted significantly better antitumor activity than S-1 or nab-paclitaxel alone. Thymidylate synthase, OPRT, and DPD were possibly biomarkers of S-1 and HER2 of nab-paclitaxel.

Diagnostic and therapeutic biomarkers in pancreaticobiliary malignancy

Pancreatic ductal adenocarcinoma (PDAC) and cholangiocarcinoma (CCA) are two malignancies that carry significant morbidity and mortality. The poor prognoses of these cancers are strongly related to lack of effective screening modalities as well as few therapeutic options. In this review, we highlight novel biomarkers that have the potential to be used as diagnostic, prognostic and predictive markers. The focus of this review is biomarkers that can be evaluated on endoscopically-obtained biopsies or brush specimens in the pre-operative setting. We also provide an overview of novel serum based markers in the early diagnosis of both PDAC and CCA. In pancreatic cancer, the emphasis is placed on prognostic and theranostic markers, whereas in CCA the utility of molecular markers in diagnosis and prognosis are highlighted.

Targeting of cancer‑associated fibroblasts enhances the efficacy of cancer chemotherapy by regulating the tumor microenvironment

Cancer-associated fibroblasts (CAFs), key components of the tumor stroma, can regulate tumorigenesis by altering the tumor microenvironment in variety of ways to promote angiogenesis, recruit inflammatory immune cells and remodel the extracellular matrix. Using a murine xenograft model of colon carcinoma, the present study observed that oxaliplatin increased the accumulation of CAFs and stimulated the production of cytokines associated with CAFs. When oxaliplatin was combined with the small-molecule dipeptidyl peptidase inhibitor PT-100, which inhibits CAFs by targeting fibroblast activation protein (FAP), the accumulation of CAFs was markedly reduced, xenograft tumor growth was significantly suppressed and the survival of the mice increased, compared to those of mice treated with oxaliplatin or PT-100 alone. Furthermore, the xenograft tumor tissues of mice treated with oxaliplatin and PT-100 contained lower numbers of tumor-associated macrophages and dendritic cells, expressed lower levels of cytokines associated with CAFs and had a lower density of CD31+ endothelial cells. The present study demonstrated that pharmacological inhibition of CAFs improved the response to chemotherapy, reduced the recruitment of immune tumor-promoting cells and inhibited angiogenesis. Combining chemotherapy with agents which target CAFs may represent a novel strategy for improving the efficacy of chemotherapy and reducing chemoresistance.

Current standards and new innovative approaches for treatment of pancreatic cancer

Pancreatic adenocarcinoma remains a devastating disease with a 5-year survival rate not exceeding 6%. Treatment of this disease remains a major challenge. This article reviews the state-of-the-art in the management of this disease and the new innovative approaches that may help to accelerate progress in treating its victims. After careful pre-therapeutic evaluation, only 15-20% of patients diagnosed with a pancreatic cancer (PC) are eligible for upfront radical surgery. After R0 or R1 resection in such patients, evidence suggests a significantly positive impact on survival of adjuvant chemotherapy comprising 6 months of gemcitabine or fluorouracil/folinic acid. Delayed adjuvant chemoradiation is considered as an option in cases of positive margins. Borderline resectable pancreatic cancer (BRPC) is defined as a tumour involving the mesenteric vasculature to a limited extend. Resection of these tumours is technically feasible, yet runs the high risk of a R1 resection. Neoadjuvant treatment probably offers the best chance of achieving successful R0 resection and long-term survival, but the best treatment options should be determined in prospective randomised studies. Gemcitabine has for 15 years been the only validated therapy for advanced PC. Following decades of negative phase III studies, increasing evidence now suggests that further significant improvements to overall survival can be achieved via either Folfirinox or gemcitabine + nab-paclitaxel regimens. Progress in systemic therapy may improve the chances of resection in borderline resectable pancreatic cancer (BRPC) or locally advanced PC. This requires first enhancing knowledge of the genetic events driving carcinogenesis, which may then be translated into clinical studies.

Toward stratification of patients with pancreatic cancer: Past lessons from traditional approaches and future applications with physical biomarkers

Pancreatic ductal adenocarcinoma (PDAC) has a high mortality rate and outcomes have not improved substantially for decades. Significant attention has focused on the biological drivers of the disease, and preclinical work has pointed to multiple biomarker candidates and therapeutic avenues. However, translation of these promising biomarkers and treatment strategies to patients has not been overwhelmingly successful. New strategies to account for the significant heterogeneity of the disease are needed so that rational treatments can be administered. Here, we focus on how physical sciences-based approaches may play a role in stratifying patients for clinical trials, and how this view of PDAC may reinvigorate treatment strategies that have been abandoned after "failing" to fulfill their potential in unselected patient populations. By complementing biological approaches, the development of physical biomarkers of PDAC may help deliver on the promise of personalized medicine for this devastating disease.

Evolving Evidence of the Efficacy and Safety of nab-Paclitaxel in the Treatment of Cancers with Squamous Histologies

Taxanes, such as paclitaxel and docetaxel, are well-established cytotoxic chemotherapeutics used in the treatment of a variety of cancers, including those of squamous histology. In their formulation, both agents require solvents, which have been associated with hypersensitivity reactions, peripheral neuropathy, hepatic toxicities, and impaired drug delivery. nab-Paclitaxel is a novel, albumin-bound form of paclitaxel with improved tolerability, bioavailability, and efficacy compared with solvent-based paclitaxel. Currently, nab-paclitaxel is approved for the treatment of metastatic breast cancer, locally advanced/metastatic non-small cell lung cancer (NSCLC), and metastatic pancreatic cancer. Clinical studies suggest that nab-paclitaxel may be particularly effective in cancers with squamous histology, including NSCLC. This article reviews the emerging evidence supporting nab-paclitaxel as an effective agent in the treatment of malignancies of squamous histology.

Prognostic Value of SPARC in Patients with Pancreatic Cancer: A Systematic Review and Meta-Analysis

OBJECTIVE

There is a heated debate on whether the prognostic value of SPARC is favorable or unfavorable. Thus, we carried out a meta-analysis evaluating the relationship between SPARC expression and the prognosis of patients with pancreatic cancer.

METHODS

We searched PubMed, EMBASE and Web of Science for relevant articles. The pooled hazard ratios (HRs) and corresponding 95%CI of overall survival (OS) were calculated to evaluate the prognostic value of SPARC expression in patients with pancreatic cancer. We also performed subgroup analyses.

RESULTS

With 1623 patients pooled from 10 available studies, the incorporative HR showed an unfavorable prognosis of patients with pancreatic cancer in the multivariate analysis (HR = 1.55, 95%CI: 1.11-2.17, P = 0.01), but not in univariate analysis (HR = 1.41, 95%CI: 0.47-4.21, P = 0.54) and estimate (HR = 1.24, 95%CI: 0.72-2.13, P = 0.44). And this adverse impact could also be found in the subgroup analyses in multivariate analysis, especially in the stroma (HR = 1.53, 95%CI: 1.05-2.24, P = 0.03). However, the combined HR had the highly significant heterogeneity. No obvious publication bias was found.

CONCLUSIONS

SPARC might be an unfavorable indicator in patients with pancreatic cancer, especially in the stroma. More and further researches should be conducted to reveal the prognostic value of SPARC.

Adjuvant therapy for pancreas cancer in an era of value based cancer care

In resected pancreas cancer, adjuvant therapy improves outcomes and is considered the standard of care for patients who recover sufficiently post operatively. Chemotherapy or combined chemotherapy and radiation therapy (chemoradiation; CRT) are strategies used in the adjuvant setting. However, there is a lack of evidence to suggest whether the addition of RT to chemotherapy translates to an improvement in clinical outcomes. This is true even when accounting for the subset of patients with a higher risk for recurrence, such as those with R1 and lymph node positive disease. When considering the direct and indirect costs, impact on quality of life and questionable added clinical benefit, the true "net health benefit" from added RT to chemotherapy becomes more uncertain. Future directions, including the utilization of modern RT, integration of novel therapies, and intensifying chemotherapy regimens may improve outcomes in resected pancreas cancer.

Current situation and predicament of multidisciplinary treatment of pancreatic cancer

Pancreatic adenocarcinoma is one of the deadliest solid malignancies. As the anatomy position of the pancreas is deep, most patients are difficult to diagnose in the early stage. Approximately 40% of patients are diagnosed with locally advanced or metastatic disease at the time of diagnosis, which severely limits the number of patients who can undergo surgical resection. There is an urgent need to explore new treatments or comprehensive treatment for pancreatic cancer, in order to improve the long-term survival rate and quality of life. Recent therapeutic advances for advanced pancreatic cancer have improved overall survival, but the prognosis remains grim. This article reviews both the major therapeutic strategies and their predicaments for pancreatic adenocarcinoma, including currently ongoing clinical trials about use of the new agents and technologies.

Immunological landscape and immunotherapy of hepatocellular carcinoma

Advanced hepatocellular carcinoma (HCC) is a serious therapeutic challenge and targeted therapies only provide a modest benefit in terms of overall survival. Novel approaches are urgently needed for the treatment of this prevalent malignancy. Evidence demonstrating the antigenicity of tumour cells, the discovery that immune checkpoint molecules have an essential role in immune evasion of tumour cells, and the impressive clinical results achieved by blocking these inhibitory receptors, are revolutionizing cancer immunotherapy. Here, we review the data on HCC immunogenicity, the mechanisms for HCC immune subversion and the different immunotherapies that have been tested to treat HCC. Taking into account the multiplicity of hyperadditive immunosuppressive forces acting within the HCC microenvironment, a combinatorial approach is advised. Strategies include combinations of systemic immunomodulation and gene therapy, cell therapy or virotherapy.

Pericytes Promote Malignant Ovarian Cancer Progression in Mice and Predict Poor Prognosis in Serous Ovarian Cancer Patients

PURPOSE

The aim of this study was to investigate the role of pericytes in regulating malignant ovarian cancer progression.

EXPERIMENTAL DESIGN

The pericyte mRNA signature was used to interrogate ovarian cancer patient datasets to determine its prognostic value for recurrence and mortality. Xenograft models of ovarian cancer were used to determine if co-injection with pericytes affected tumor growth rate and metastasis, whereas co-culture models were utilized to investigate the direct effect of pericytes on ovarian cancer cells. Pericyte markers were used to stain patient tissue samples to ascertain their use in prognosis.

RESULTS

Interrogation of two serous ovarian cancer patient datasets [the Australian Ovarian Cancer Study, n= 215; and the NCI TCGA (The Cancer Genome Atlas), n= 408] showed that a high pericyte score is highly predictive for poor patient prognosis. Co-injection of ovarian cancer (OVCAR-5 & -8) cells with pericytes in a xenograft model resulted in accelerated ovarian tumor growth, and aggressive metastases, without altering tumor vasculature. Pericyte co-culture in vitro promoted ovarian cancer cell proliferation and invasion. High αSMA protein levels in patient tissue microarrays were correlated with more aggressive disease and earlier recurrence.

CONCLUSIONS

High pericyte score provides the best means to date of identifying patients with ovarian cancer at high risk of rapid relapse and mortality (mean progression-free survival time < 9 months). The stroma contains rare yet extremely potent locally resident mesenchymal stem cells-a subset of "cancer-associated fibroblasts" that promote aggressive tumor growth and metastatic dissemination, underlying the prognostic capacity of a high pericyte score to strongly predict earlier relapse and mortality.

Pancreatic cancer: Classifying pancreatic cancer using gene expression profiling

Despite some advances in our understanding of the molecular characteristics of pancreatic cancer, much more progress is needed. In a new study, RNA profiling of pancreatic cancers was used to identify gene signatures of tumour cells and stromal cells to help predict patient outcomes.

The inflammatory milieu within the pancreatic cancer microenvironment correlates with clinicopathologic parameters, chemoresistance and survival

Background

The tumor microenvironment impacts pancreatic cancer (PC) development, progression and metastasis. How intratumoral inflammatory mediators modulate this biology remains poorly understood. We hypothesized that the inflammatory milieu within the PC microenvironment would correlate with clinicopathologic findings and survival.

Methods

Pancreatic specimens from normal pancreas (n = 6), chronic pancreatitis (n = 9) and pancreatic adenocarcinoma (n = 36) were homogenized immediately upon resection. Homogenates were subjected to multiplex analysis of 41 inflammatory mediators.

Results

Twenty-three mediators were significantly elevated in adenocarcinoma specimens compared to nonmalignant controls. Increased intratumoral IL-8 concentrations associated with larger tumors (P = .045) and poor differentiation (P = .038); the administration of neoadjuvant chemotherapy associated with reduced IL-8 concentrations (P = .003). Neoadjuvant therapy was also associated with elevated concentrations of Flt-3 L (P = .005). Elevated levels of pro-inflammatory cytokines IL-1β (P = .017) and TNFα (P = .033) were associated with a poor histopathologic response to neoadjuvant therapy. Elevated concentrations of G-CSF (P = .016) and PDGF-AA (P = .012) correlated with reduced overall survival. Conversely, elevated concentrations of FGF-2 (P = .038), TNFα (P = .031) and MIP-1α (P = .036) were associated with prolonged survival.

Conclusion

The pancreatic cancer microenvironment harbors a unique inflammatory milieu with potential diagnostic and prognostic value.

A randomized phase II study of weekly nab-paclitaxel plus gemcitabine or simplified LV5FU2 as first-line therapy in patients with metastatic pancreatic cancer: the AFUGEM GERCOR trial

BACKGROUND

Metastatic pancreatic adenocarcinoma (PAC) prognosis remains dismal and gemcitabine monotherapy has been the standard treatment over the last decade. Currently, two first-line regimens are used in this setting: FOLFIRINOX and nab-paclitaxel plus gemcitabine. Increasing translational data on the predictive value of hENT1 for determining gemcitabine efficacy suggest that a non-gemcitabine-based regimen is favored in about 60 % of patients with PAC due to high resistance of PAC to this cytotoxic drug. This study aims to evaluate the efficacy of weekly nab-paclitaxel combined with gemcitabine or a simplified (s) LV5FU2 regimen in patients with previously untreated metastatic PAC.

METHODS/DESIGN

AFUGEM is a two-stage, open-label, randomized, multicenter, phase II trial. Patients with PAC who meet the inclusion criteria and provide written informed consent will be randomized in a 1:2 ratio to either nab-paclitaxel (125 mg/m(2)) plus gemcitabine (1000 mg/m(2)) given on days 1, 8, and 15 every 28 days or nab-paclitaxel (125 mg/m(2)) plus sLV5FU2 (leucovorin 400 mg/m(2) followed by bolus 400 mg/m(2) 5-fluorouracil and by 5-fluorouracil 2400 mg/m(2) as an 46-h intravenous infusion) given on days 1 and 15 every 28 days. A total of 114 patients will be randomized to one of the treatment arms. The primary endpoint is progression-free survival at 4 months. Secondary outcomes are rate and duration of response, disease control, overall survival, safety, and quality of life. Potential biomarkers of gemcitabine (hENT1, dCK) and 5-fluorouracil (TS) efficacy will be assessed.

DISCUSSION

The AFUGEM trial is designed to provide valuable information regarding efficacy and tolerability of nab-paclitaxel plus gemcitabine and nab-paclitaxel plus sLV5FU2 regimens. Identification of potential predictive biomarkers of gemcitabine and 5-fluorouracil is likely to drive therapeutic decisions in patients with metastatic PAC.

TRIAL REGISTRATION

AFUGEM is registered at Clinicaltrials.gov: NCT01964534 , October 15, 2013.

Cancer Genetics and Implications for Clinical Management

There is now compelling evidence that the molecular heterogeneity of cancer is associated with disparate phenotypes with variable outcomes and therapeutic responsiveness to therapy in histologically indistinguishable cancers. This diversity may explain why conventional clinical trial designs have mostly failed to show efficacy when patients are enrolled in an unselected fashion. Knowledge of the molecular phenotype has the potential to improve therapeutic selection and hence the early delivery of the optimal therapeutic regimen. Resolution of the challenges associated with a more stratified approach to health care will ensure more precise diagnostics and enhance therapeutic selection, which will improve overall outcomes.

New avenues for improving pancreatic ductal adenocarcinoma (PDAC) treatment: Selective stroma depletion combined with nano drug delivery

The effectiveness of chemotherapy in PDAC is hampered by the dynamic interaction between stroma and cancer cell. The two opposing schools of thought - non-depletion of the stroma vs its depletion - to better drug efficacy are here discussed. Disrupting stroma-cancer cell interaction to reduce tumor progression and promote apoptosis is identified as the new direction of treatment for PDAC. Clinical data have shown that elimination of fibrosis and blockade of the Hedgehog pathway in stroma effectively promote drug delivery to tumor site and apoptosis. Reduced stiffness of ECM, lower fibrosis, higher permeability and higher blood flow after stroma depletion increase drug delivery. Combination strategies involving selective stroma depletion coupled with chemotherapy is currently proving to be the most efficient at clinical level. Striking the right balance between fibrosis depletion and angiogenesis promotion resulting in enhanced drug delivery and apoptosis is a major challenge. The use of nano drug delivery devices coupled with stroma depletion is emerging as the next phase treatment for PDAC. The breakthrough to combat PDAC will likely be a combination of early diagnosis and the emerging chemotherapy strategies.

Functional significance of macrophages in pancreatic cancer biology

Pancreatic ductal adenocarcinoma (PDA) is a lethal disease that is usually diagnosed at late stage with few effective therapies. Despite the rapid progress on the genomics and proteomics of the neoplastic cells, therapies that targeted the pancreatic cancer cells proved to be inefficient, which promoted the researchers to turn their attentions to the microenvironment. Currently, various studies had proposed the microenvironment to be a contributing factor for PDA and pervasive researches showed that macrophages within the malignancy correlate with the malignant phenotype of the disease and were reported to a new therapeutic target. Generally, the pro-tumoral effects of macrophages can be summarized as angiogenesis promotion, immunosuppression, matrix remodeling and so on. Hence, a comprehensive understanding of the biologic behaviors of macrophages and their critical role in PDA development may provide new directions for the managements of the lethal disease. In this review, we will summarize the recent advancements on macrophages as pivotal players in PDA biology and the current knowledge about anti-macrophages as a novel strategy against cancer, with the expectation that more efficient therapies will be developed in the near future.

Personalized medicine in pancreatic cancer: the revolution has begun

Pancreatic ductal adenocarcinoma carries a dismal prognosis. Both chemotherapy and targeted therapies have been disappointing when administered to unselected populations. Recently, progress has been made in our understanding of the genomic landscape of this cancer which displays remarkable heterogeneity suggesting a reorientation of management and research strategies based on molecular characterization and adapted personalized therapy. Resectable disease offers new opportunities for translational research through functional imaging response evaluation and tumor tissue acquisition before and after neoadjuvant therapy. There is urgent need for clinical trials based on molecular profiling in pancreatic ductal adenocarcinoma. In this review we discuss opportunities and limitations of these new strategies, underlining the importance of tissue acquisition and integration of molecular biomarkers in future molecularly driven clinical trials.

Pancreatic cancer genomics: where can the science take us?

The incidence of pancreatic ductal adenocarcinoma (PDAC) is steadily increasing and the annual death-to-incidence ratio approaches one. This is a figure that has not changed for several decades. Surgery remains the only chance of cure; however, only less than 20% of patients are amenable to operative resection. Despite successful surgical resection, the majority of the patients still succumb to recurrent metastatic disease. Therefore, there is an urgent need to develop novel therapeutic strategies and to better select patients for current therapies. In this review, we will discuss current management by highlighting the landmark clinical trials that have shaped current care. We will then discuss the challenges of therapeutic development using the current randomized-controlled trial paradigm when confronted with the molecular heterogeneity of PDAC. Finally, we will discuss strategies that may help to shape the management of PDAC in the near future.

Cancer-associated fibroblasts in pancreatic adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most highly malignant tumors with a very poor prognosis. In addition to the cancer cells, the stroma of tumor can expand by 50% and influence cancer cell growth. Cancer-associated fibroblasts (CAFs) are important components of tumor stroma. Cancer cells, normal fibroblasts, normal epithelial cells as well as bone marrow-derived myofibroblasts contribute to the emergence of CAFs through various cytokines (e.g., TGF-β, SHH, PDGF) and epithelial-to-mesenchymal transition. CAFs affect cancer growth, survival, metastasis, angiogenesis and immunosurveillance through the secretion of various cytokines, such as CXCL12 and secreted protein acidic and rich in cystein. Also, CAFs correlate to the prognosis and chemoresistance of PDAC patients. As novel therapeutic targets, CAFs, and their relative factors, represent an important role in PDAC therapy.

Peritumoral SPARC expression and patient outcome with resectable intrahepatic cholangiocarcinoma

Background and objectives

Cholangiocarcinoma (CCA) affects thousands worldwide with increasing incidence. SPARC (secreted protein acidic and rich in cysteine) plays an important role in cellular matrix interactions, wound repair, and cellular migration, and has been reported to prevent malignancy from growth. SPARC undergoes epigenetic silencing in pancreatic malignancy, but is frequently expressed by stromal fibroblasts adjacent to infiltrating pancreatic adenocarcinomas. CCA is also a desmoplastic tumor, similar to pancreatic adenocarcinoma. SPARC’s clinical influence on clinicopathological characteristics of mass-forming (MF)-CCA still remains unclear. In this study, we evaluate the expression of SPARC in tumor and stromal tissue to clarity its relation with prognosis.

Methods

Seventy-eight MF-CCA patients who underwent hepatectomy with curative intent were enrolled for an immunohistochemical study of SPARC. The expression of immunostaining of SPARC was characterized for both tumor and stromal tissues. We conducted survival analysis with 16 clinicopathological variables. The overall survival (OS) was analyzed by Kaplan–Meier analysis and Cox proportional hazards regression modeling.

Results

Thirty-three men and 45 women with MF-CCA were studied. Within total 78 subjects, 12 (15.4%) were classified as tumor negative/stroma negative, 37 (47.4%) as tumor positive/stroma negative, four (5.1%) as tumor negative/stroma positive, and 25 (32.1%) as tumor positive/stroma positive. With a median follow-up of 13.6 months, the 5-year OS was 14.9%. Cox proportional hazard analysis revealed that SPARC tumor positive and stromal negative immunostaining and curative hepatectomy predicted favorable OS in patients with MF-CCA after hepatectomy.

Conclusion

MF-CCA patients with SPARC tumor positive and stromal negative expression may have favorable OS rates after curative hepatectomy.

SPARC Expression Did Not Predict Efficacy of nab-Paclitaxel plus Gemcitabine or Gemcitabine Alone for Metastatic Pancreatic Cancer in an Exploratory Analysis of the Phase III MPACT Trial

PURPOSE

nab-Paclitaxel plus gemcitabine was superior to gemcitabine alone for patients with metastatic pancreatic cancer (MPC) in the phase III MPACT trial. This study evaluated the association of secreted protein acidic and rich in cysteine (SPARC) levels with efficacy as an exploratory endpoint.

EXPERIMENTAL DESIGN

Patients with previously untreated MPC (N = 861) received nab-paclitaxel plus gemcitabine or gemcitabine alone. Baseline SPARC level was measured in the tumor stroma and epithelia (archival biopsies) and plasma. Experiments were performed in pancreatic cancer mouse models in which SPARC was intact or deleted.

RESULTS

SPARC was measured in the tumor stroma of 256 patients (30%), the tumor epithelia of 301 patients (35%), and plasma of 343 patients (40%). Stroma-evaluable samples were from metastases (71%), from the pancreas (11%), or of unidentifiable origin (insufficient tissue to determine; 17%). For all patients, stromal SPARC level [high (n = 71) vs. low (n = 185)] was not associated with overall survival (OS; HR, 1.019; P = 0.903); multivariate analysis confirmed this lack of association. There was no association between stromal SPARC level and OS in either treatment arm. Neither tumor epithelial SPARC nor plasma SPARC was associated with OS. Results from a SPARC knockout mouse model treated with nab-paclitaxel plus gemcitabine revealed no correlation between SPARC expression and tumor progression or treatment efficacy.

CONCLUSIONS

SPARC levels were not associated with efficacy in patients with MPC. This exploratory analysis does not support making treatment decisions regarding nab-paclitaxel plus gemcitabine or gemcitabine alone in MPC based on SPARC expression.

Prognostic value of SPARC expression in unresectable NSCLC treated with concurrent chemoradiotherapy

BACKGROUND

The aim of the present study was to determine the predictive/prognostic value of the secreted protein, acidic and rich in cysteine (SPARC) in cases of unresectable, locally advanced, non-small cell lung cancer.

MATERIALS AND METHODS

The study included 84 patients with Stage IIIA-B non-small cell lung cancer, undergoing simultaneous chemoradiotherapy including radiotherapy at a dose of 66 Gy and weekly docataxel (20 mg/m2) and cisplatin (20 mg/m2). SPARC expression was studied in biopsy material by immunohistochemical methods and correlations with treatment responses or survival were evaluated.

RESULTS

Median overall survival was 16±2.73 (11.55-20.46) months for low expression vs 7±1.79 months (7.92-16.08) months for high expression (p=0.039), while median local control was 13±2.31 (8.48-17.5) months for low expression vs 6±0.85 (4.34-7.66) months for high expression (p=0.045) and median progression-free survival was 10±2.31 (5.48-14.5) months for low expression vs 6±1.10 (3.85-8.15) months for high expression (p=0.022). In both univariate and multivariate analyses, high SPARC expression was associated with significantly shorter overall survival (p=0.003, p=0.007, respectively), local control (p=0.008, p=0.036) and progression-free survival (p=0.004, p=0.029) when compared to low SPARC expression. No significant difference was detected between high and low SPARC expression groups regarding age, sex, T stage, N stage, histopathology and stage-related patient characteristics.

CONCLUSIONS

High SPARC expression was identified as a poor prognostic factor in cases with locally advanced NSCLC treated with concurrent chemoradiotherapy.

Pancreatic cancer: optimizing treatment options, new, and emerging targeted therapies

Pancreatic cancer is the fourth leading cause of cancer death in the US and is expected to become the second leading cause of cancer-related deaths in the next decade. Despite 5-fluorouracil/leucovorin with irinotecan and oxaliplatin (FOLFIRINOX) and gemcitabine/nab-paclitaxel significantly improving outcomes for metastatic cancer, refractory disease still poses significant challenges. Difficulties with early detection and the inherent chemo- and radio-resistant nature of this malignancy led to attempts to define the sequential biology of pancreatic cancer in order to improve survival outcomes. Pancreatic adenocarcinoma is characterized by several germline or acquired genetic mutations, the most common being KRAS (90%), CDK2NA (90%), TP53 (75%-90%), DPC4/SMAD4 (50%). In addition, the tumor microenvironment, chemoresistant cancer stem cells, and the desmoplastic stroma have been the target of some promising clinical investigations. Among the core pathways reproducibly shown to lead the development and progression of this disease, DNA repair, apoptosis, G1/S cell cycle transition, KRAS, Wnt, Notch, Hedgehog, TGF-beta, and other cell invasion pathways, have been the target of "precision therapeutics". No single molecularly targeted therapeutic though has been uniformly successful, probably due to the tumor heterogeneity, but biomarker research is evolving and it hopes to select more patients likely to benefit. Recent reports note activity with immunotherapies such as CD40 agonists, CCR2 inhibitors, cancer vaccines, and novel combinations against the immunosuppressive tumor milieu are ongoing. While many obstacles still exist, clearly we are making progress in deciphering the heterogeneity within pancreatic cancers. Integrating conventional and immunological targeting will be the key to effective treatment of this deadly disease.

Pancreatic cancer stromal biology and therapy

Pancreatic cancer is one of the most lethal malignancies. Significant progresses have been made in understanding of pancreatic cancer pathogenesis, including appreciation of precursor lesions or premalignant pancreatic intraepithelial neoplasia (PanINs), description of sequential transformation from normal pancreatic tissue to invasive pancreatic cancer and identification of major genetic and epigenetic events and the biological impact of those events on malignant behavior. However, the currently used therapeutic strategies targeting tumor epithelial cells, which are potent in cell culture and animal models, have not been successful in the clinic. Presumably, therapeutic resistance of pancreatic cancer is at least in part due to its drastic desmoplasis, which is a defining hallmark for and circumstantially contributes to pancreatic cancer development and progression. Improved understanding of the dynamic interaction between cancer cells and the stroma is important to better understanding pancreatic cancer biology and to designing effective intervention strategies. This review focuses on the origination, evolution and disruption of stromal molecular and cellular components in pancreatic cancer, and their biological effects on pancreatic cancer pathogenesis.

[Nab-paclitaxel]

Paclitaxel is conventionally used in a wide range of oncology indications. Nab-paclitaxel is synthesized by a process of high pressure homogenization of paclitaxel in the presence of human albumin and it was originally developed to reduce the toxicity usually associated with cremophor in soluble paclitaxel and to increase its penetration in tumor tissues. After the trials that led to its approval in first-line treatment of metastatic pancreatic carcinomas and in second line therapy for metastatic breast cancer, nab-paclitaxel is being tested for many other situations in oncology due to its profile of security and its good tolerance. Different lines of research are being developed about the possible biomarkers that could predict the effect of nab-paclitaxel. This review summarizes the results of trials that led to the approval of the nab-paclitaxel in advanced breast cancer and pancreatic cancer, and also resumes the lines of research to the future development of the drug.

Republished: Importance of carcinoma-associated fibroblast-derived proteins in clinical oncology

Carcinoma-associated fibroblast (CAF) as prominent cell type of the tumour microenvironment has complex interaction with both the cancer cells and other non-neoplastic surrounding cells. The CAF-derived regulators and extracellular matrix proteins can support cancer progression by providing a protective microenvironment for the cancer cells via reduction of chemotherapy sensitivity. On the other hand, these proteins may act as powerful prognostic markers as well as potential targets of anticancer therapy. In this review, we summarise the clinical importance of the major CAF-derived signals influencing tumour behaviour and determining the outcome of chemotherapy.

Targeting of metastasis-promoting tumor-associated fibroblasts and modulation of pancreatic tumor-associated stroma with a carboxymethylcellulose-docetaxel nanoparticle

Pancreatic ductal adenocarcinomas are characterized by the desmoplastic reaction, a dense fibrous stroma that has been shown to be supportive of tumor cell growth, invasion, and metastasis, and has been associated with resistance to chemotherapy and reduced patient survival. Here, we investigated targeted depletion of stroma for pancreatic cancer therapy via taxane nanoparticles. Cellax-DTX polymer is a conjugate of docetaxel (DTX), polyethylene glycol (PEG), and acetylated carboxymethylcellulose, a construct which condenses into well-defined 120nm particles in an aqueous solution, and is suitable for intravenous injection. We examined Cellax-DTX treatment effects in highly stromal primary patient-derived pancreatic cancer xenografts and in a metastatic PAN02 mouse model of pancreatic cancer, focusing on specific cellular interactions in the stroma, pancreatic tumor growth and metastasis. Greater than 90% of Cellax-DTX particles accumulate in smooth muscle actin (SMA) positive cancer-associated fibroblasts which results in long-term depletion of this stromal cell population, an effect not observed with Nab-paclitaxel (Nab-PTX). The reduction in stromal density leads to a >10-fold increase in tumor perfusion, reduced tumor weight and a reduction in metastasis. Consentingly, Cellax-DTX treatment increased survival when compared to treatment with gemcitabine or Nab-PTX in a metastatic PAN02 mouse model. Cellax-DTX nanoparticles interact with the tumor-associated stroma, selectively interacting with and depleting SMA positive cells and macrophage, effects of which are associated with significant changes in tumor progression and metastasis.

Update on the management of pancreatic cancer: Surgery is not enough

Pancreatic ductal adenocarcinoma (PDAC) represents the fourth cause of death in cancer and has a 5-year survival of < 5%. Only about 15% of the patients present with a resectable PDAC with potential to undergo “curative” surgery. After surgery, local and systemic recurrence, is though very common. The median survival of resected patients with adjuvant chemotherapy after surgery is only 20-23 mo. This underscores the significant need to improve PDAC management strategies. Increased survival rate is dependent on new breakthroughs in our understanding of not at least tumor biology. The aim of this review is to update and comment on recent knowledge concerning PDAC biology and new diagnostics and treatment modalities. One fundamental approach to improve survival rates is by earlier and improved diagnosis of the disease. In recent years, novel blood-based biomarkers have emerged based on genetic, epigenetic and protein changes in PDAC with very promising results. For biomarkers to enter clinical practice they need to have been developed using adequate control groups and provide high sensitivity and specificity and by this identify patients at risk already in a pre-symptomatic stage. Another way to improve outcomes, is by employing neoadjuvant treatments thereby increasing the number of resectable cases. Novel systemic treatment regimes like FOLFIRINOX and nab-paclitaxel have demonstrated improvements in prolonging survival in advanced cases, but long-term survival is still scarce. The future improved understanding of PDAC biology will inevitably render new treatment options directed against both the cancer cells and the surrounding microenvironment.

Advanced pancreatic adenocarcinoma: a review of current treatment strategies and developing therapies

Pancreatic adenocarcinoma is one of the deadliest solid malignancies. A large proportion of patients are diagnosed with locally advanced or metastatic disease at the time of presentation and, unfortunately, this severely limits the number of patients who can undergo surgical resection, which offers the only chance for cure. Recent therapeutic advances for patients with advanced pancreatic cancer have extended overall survival, but prognosis still remains grim. Given that traditional chemotherapy is ineffective in curing advanced pancreatic adenocarcinoma, current research is taking a multidirectional approach in the hopes of developing more effective treatments. This article reviews the major clinical trial data that is the basis for the current chemotherapy regimens used as first- and second-line treatments for advanced pancreatic adenocarcinoma. We also review the current ongoing clinical trials, which include the use of agents targeting the oncogenic network signaling of K-Ras, agents targeting the extracellular matrix, and immune therapies.

Epigenetic silencing of EYA2 in pancreatic adenocarcinomas promotes tumor growth

To identify potentially important genes dysregulated in pancreatic cancer, we analyzed genome-wide transcriptional analysis of pancreatic cancers and normal pancreatic duct samples and identified the transcriptional coactivator, EYA2 (Drosophila Eyes Absent Homologue-2) as silenced in the majority of pancreatic cancers. We investigated the role of epigenetic mechanisms of EYA2 gene silencing in pancreatic cancers, performed in vitro and in vivo proliferation and migration assays to assess the effect of EYA2 silencing on tumor cell growth and metastasis formation, and expression analysis to identify genes transcriptionally regulated by EYA2. We found loss of tumoral Eya2 expression in 63% of pancreatic cancers (120/189 cases). Silencing of EYA2 expression in pancreatic cancer cell lines correlated with promoter methylation and histone deacetylation and was reversible with DNA methyltransferase and HDAC inhibitors. EYA2 knockdown in pancreatic cancer cell lines increased cell proliferation. Compared to parental pancreatic cancer cells, pancreatic cancers stably-expressing EYA2 grew more slowly and had fewer metastases in orthotopic models. The transcriptional changes after stable expression of EYA2 in pancreatic cancer cells included induction of genes in the TGFbeta pathway. Epigenetic silencing of EYA2 is a common event in pancreatic cancers and stable expression EYA2 limits the growth and metastases of pancreatic adenocarcinoma.

Gene and cell therapy for pancreatic cancer

INTRODUCTION

The clinical outcomes of patients with pancreatic cancer are poor, and the limited success of classical chemotherapy underscores the need for new, targeted approaches for this disease. The delivery of genetic material to cells allows for a variety of therapeutic concepts. Engineered agents based on synthetic biology are under clinical investigation in various cancers, including pancreatic cancer.

AREAS COVERED

This review focuses on Phase I - III clinical trials of gene and cell therapy for pancreatic cancer and on future implications of recent translational research. Trials available in the US National Library of Medicine (www.clinicaltrials.gov) until February 2014 were reviewed and relevant published results of preclinical and clinical studies were retrieved from www.pubmed.gov .

EXPERT OPINION

In pancreatic cancer, gene and cell therapies are feasible and may have synergistic antitumor activity with standard treatment and/or immunotherapy. Challenges are related to application safety, manufacturing costs, and a new spectrum of adverse events. Further studies are needed to evaluate available agents in carefully designed protocols and combination regimens. Enabling personalized cancer therapy, insights from molecular diagnostic technologies will guide the development and selection of new gene-based drugs. The evolving preclinical and clinical data on gene-based therapies can lay the foundation for future avenues improving patient care in pancreatic cancer.

Prognostic factors of survival in a randomized phase III trial (MPACT) of weekly nab-paclitaxel plus gemcitabine versus gemcitabine alone in patients with metastatic pancreatic cancer

BACKGROUND

nab-Paclitaxel in combination with gemcitabine has emerged as a new treatment option for patients with metastatic pancreatic cancer (MPC), based on superiority over gemcitabine demonstrated in the phase III MPACT trial. Previously, Karnofsky performance status (KPS) score and the presence of liver metastases were shown to be predictive of survival with nab-paclitaxel plus gemcitabine treatment. This analysis sought to further explore the relationship between clinical characteristics and survival in the MPACT trial and to identify potential predictors of overall survival and progression-free survival in patients with MPC.

MATERIALS AND METHODS

Cox regression models adjusted for stratification factors and a stepwise multivariate analysis of prespecified baseline prognostic factors were performed.

RESULTS

Treatment effect was significantly associated with survival, with a similar magnitude of reduction in risk of death compared with the previously reported primary analysis. Treatment effect consistently favored nab-paclitaxel plus gemcitabine across the majority of the prespecified factors. In addition to KPS score and presence of liver metastases, age and number of metastatic sites were independent prognostic factors of overall and progression-free survival. Baseline carbohydrate antigen 19-9 was not found to be an independent prognostic factor of survival in this analysis.

CONCLUSION

The results of this analysis confirm broad utility of nab-paclitaxel plus gemcitabine for the treatment of MPC. In addition, these findings suggest that KPS score, presence of liver metastases, age, and number of metastatic sites are important predictors of survival that may be useful when making treatment decisions and designing future clinical trials.

Addressing the challenges of pancreatic cancer: future directions for improving outcomes

Pancreatic ductal adenocarcinoma (PDAC), which accounts for more than 90% of all pancreatic tumours, is a devastating malignancy with an extremely poor prognosis, as shown by a 1-year survival rate of around 18% for all stages of the disease. The low survival rates associated with PDAC primarily reflect the fact that tumours progress rapidly with few specific symptoms and are thus at an advanced stage at diagnosis in most patients. As a result, there is an urgent need to develop accurate markers of pre-invasive pancreatic neoplasms in order to facilitate prediction of cancer risk and to help diagnose the disease at an earlier stage. However, screening for early diagnosis of prostate cancer remains challenging and identifying a highly accurate, low-cost screening test for early PDAC for use in clinical practice remains an important unmet need. More effective therapies are also crucial in PDAC, since progress in identifying novel therapies has been hampered by the genetic complexity of the disease and treatment remains a major challenge. Presently, the greatest step towards improved treatment efficacy has been made in the field of palliative chemotherapy by introducing FOLFIRINOX (folinic acid, 5-fluorouracil, irinotecan and oxaliplatin) and gemcitabine/nab-paclitaxel. Strategies designed to raise the profile of PDAC in research and clinical practice are a further requirement in order to ensure the best treatment for patients. This article proposes a number of approaches that may help to accelerate progress in treating patients with PDAC, which, in turn, may be expected to improve the quality of life and survival for those suffering from this devastating disease.

Importance of carcinoma-associated fibroblast-derived proteins in clinical oncology

Carcinoma-associated fibroblast (CAF) as prominent cell type of the tumour microenvironment has complex interaction with both the cancer cells and other non-neoplastic surrounding cells. The CAF-derived regulators and extracellular matrix proteins can support cancer progression by providing a protective microenvironment for the cancer cells via reduction of chemotherapy sensitivity. On the other hand, these proteins may act as powerful prognostic markers as well as potential targets of anticancer therapy. In this review, we summarise the clinical importance of the major CAF-derived signals influencing tumour behaviour and determining the outcome of chemotherapy.

Management options in locally advanced pancreatic cancer

Pancreatic ductal adenocarcinoma is a highly lethal cancer that is rarely curable at the time of presentation. Unfortunately, most patients are diagnosed with either metastatic or locally advanced disease, which is not amenable to surgery owing to the high likelihood of incomplete resection. Given the generally poor prognosis with propensity for metastatic failure greater than that for local failure, treatment options are variable, and include chemotherapy, radiotherapy, targeted therapies, and combinations thereof. This review summarizes the current evidence for definitive management of locally advanced pancreatic adenocarcinoma, as well as the role of palliative therapies. Future directions, including the development of predictive biomarkers and novel systemic agents, are also discussed.

Stromal expression of SPARC in pancreatic adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) stands as the poorest prognostic tumor of the digestive tract, with a 5-year survival rate of less than 5%. Therapeutic options for unresectable PDAC are extremely limited and there is a pressing need for expanded therapeutic approaches to improve current options available with gemcitabine-based regimens. With PDAC displaying one of the most prominent desmoplastic stromal reactions of all carcinomas, recent research has focused on the microenvironment surrounding PDAC cells. Secreted protein acid and rich in cysteine (SPARC), which is overexpressed in PDAC, may display tumor suppressor functions in several cancers (e.g., in colorectal, ovarian, prostate cancers, and acute myelogenous leukemia) but also appears to be overexpressed in other tumor types (e.g., breast cancer, melanoma, and glioblastoma). The apparent contradictory functions of SPARC may yield inhibition of angiogenesis via inhibition of vascular endothelial growth factor, while promoting epithelial-to-mesenchymal transition and invasion through matrix metalloprotease expression. This feature is of particular interest in PDAC where SPARC overexpression in the stroma stands along with inhibition of angiogenesis and promotion of cancer cell invasion and metastasis. Several therapeutic strategies to deplete stromal tissue have been developed. In this review, we focused on key preclinical and clinical data describing the role of SPARC in PDAC biology, the properties, and mechanisms of delivery of drugs that interact with SPARC and discuss the proof-of-concept clinical trials using nab-paclitaxel.

Neoadjuvant therapy for pancreas cancer: Past lessons and future therapies

Pancreatic adenocarcinoma remains a most deadly malignancy, with an overall 5-year survival of 5%. A subset of patients will be diagnosed with potentially resectable disease, and while complete surgical resection provides the only chance at cure, data from trials of postoperative chemoradiation and/or chemotherapy demonstrate a modest survival advantage over those patients who undergo resection alone. As such, most practitioners believe that completion of multimodality therapy is the optimal treatment. However, the sequence of surgery, chemotherapy and radiation therapy is frequently debated, as patients may benefit from a neoadjuvant approach by initiating chemotherapy and/or chemoradiation prior to resection. Here we review the rationale for neoadjuvant therapy, which includes a higher rate of completion of multimodality therapy, minimizing the risk of unnecessary surgical resection for patients who develop early metastatic disease, improved surgical outcomes and the potential for longer overall survival. However, there are no prospective, randomized studies of the neoadjuvant approach compared to a surgery-first strategy; the established and ongoing investigations of neoadjuvant therapy for pancreatic cancer are discussed in detail. Lastly, as the future of therapeutic regimens is likely to entail patient-specific genetic and molecular analyses, and the treatment that is best applied based on those data, a review of clinically relevant biomarkers in pancreatic cancer is also presented.