Total Neoadjuvant Therapy With FOLFIRINOX in Combination With Losartan Followed by Chemoradiotherapy for Locally Advanced Pancreatic Cancer: A Phase 2 Clinical Trial

Cancer-Associated Fibroblast Diversity Shapes Tumor Metabolism in Pancreatic Cancer

Despite extensive research, the 5-year survival rate of pancreatic cancer (PDAC) patients remains at only 9%. Patients often show poor treatment response, due partly to a highly complex tumor microenvironment (TME). Cancer-associated fibroblast (CAF) heterogeneity is characteristic of the pancreatic TME, where several CAF subpopulations have been identified, such as myofibroblastic CAFs (myCAFs), inflammatory CAFs (iCAFs), and antigen presenting CAFs (apCAFs). In PDAC, cancer cells continuously adapt their metabolism (metabolic switch) to environmental changes in pH, oxygenation, and nutrient availability. Recent advances show that these environmental alterations are all heavily driven by stromal CAFs. CAFs and cancer cells exchange cytokines and metabolites, engaging in a tight bidirectional crosstalk, which promotes tumor aggressiveness and allows constant adaptation to external stress, such as chemotherapy. In this review, we summarize CAF diversity and CAF-mediated metabolic rewiring, in a PDAC-specific context. First, we recapitulate the most recently identified CAF subtypes, focusing on the cell of origin, activation mechanism, species-dependent markers, and functions. Next, we describe in detail the metabolic crosstalk between CAFs and tumor cells. Additionally, we elucidate how CAF-driven paracrine signaling, desmoplasia, and acidosis orchestrate cancer cell metabolism. Finally, we highlight how the CAF/cancer cell crosstalk could pave the way for new therapeutic strategies.

Surgical resection rates after neoadjuvant therapy for localized pancreatic ductal adenocarcinoma: meta-analysis

BACKGROUND

Neoadjuvant therapy is increasingly being used before surgery for localized pancreatic cancer. Given the importance of completing multimodal therapy, the aim of this study was to characterize surgical resection rates after neoadjuvant therapy as well as the reasons for, and long-term prognostic impact of, not undergoing resection.

METHODS

A systematic review and meta-analysis of prospective trials and high-quality retrospective studies since 2010 was performed to calculate pooled resection rates using a generalized random-effects model for potentially resectable, borderline resectable, and locally advanced pancreatic cancer. Median survival times were calculated using random-effects models for patients who did and did not undergo resection.

RESULTS

In 125 studies that met the inclusion criteria, neoadjuvant therapy consisted of chemotherapy (36.8 per cent), chemoradiation (15.2 per cent), or chemotherapy and radiation (48.0 per cent). Among 11 713 patients, the pooled resection rates were 77.4 (95 per cent c.i. 71.3 to 82.5), 60.6 (54.8 to 66.1), and 22.2 (16.7 to 29.0) per cent for potentially resectable, borderline resectable, and locally advanced pancreatic cancer respectively. The most common reasons for not undergoing resection were distant progression for resectable and borderline resectable cancers, and local unresectability for locally advanced disease. Among 42 studies with survival data available, achieving surgical resection after neoadjuvant therapy was associated with improved survival for patients with potentially resectable (median 38.5 versus 13.3 months), borderline resectable (32.3 versus 13.9 months), and locally advanced (30.0 versus 14.6 months) pancreatic cancer (P < 0.001 for all).

CONCLUSION

Although rates of surgical resection after neoadjuvant therapy vary based on anatomical stage, surgery is associated with improved survival for all patients with localized pancreatic cancer. These pooled resection and survival rates may inform patient-provider decision-making and serve as important benchmarks for future prospective trials.

Landmarks in pancreatic cancer studies

Pancreatic cancer is a rare but fatal disease. Patients present advanced disease due to the lack of or typical symptoms when the tumor is still localized. A high-quality image processing system has been in practice to detect the pancreatic tumor and determine the possibility of surgery, and preoperative methods, such as ERCP are increasingly used to complement the staging modality. Pancreaticoduodenectomy is one of the complicated surgeries with potential morbidity. The minimally invasive pancreatic resections, both robot-assisted and laparoscopic, have become a part of standard surgical practice worldwide over the last decade. Moreover, advancements in adjuvant chemotherapy have improved the long-term outcomes in current clinical practice. The systemic conservative treatment, including targeted agents, remains the mainstay of treatment for patients with advanced disease. An increasing number of studies are focused on modulating the pancreatic tumor microenvironment to improve the efficacy of the immunotherapeutic strategies. Herein, the role of preoperative therapy, the novel surgical strategy, and individualized systemic treatment in pancreatic cancer is investigated. Also, the randomized controlled studies that have defined the neoadjuvant and surgical management of pancreatic cancer have been summarized.

Biophysical heterogeneity of myeloid-derived microenvironment to regulate resistance to cancer immunotherapy

Despite the advances in immunotherapy for cancer treatment, patients still obtain limited benefits, mostly owing to unrestrained tumour self-expansion and immune evasion that exploits immunoregulatory mechanisms. Traditionally, myeloid cells have a dominantly immunosuppressive role. However, the complicated populations of the myeloid cells and their multilateral interactions with tumour/stromal/lymphoid cells and physical abnormalities in the tumour microenvironment (TME) determine their heterogeneous functions in tumour development and immune response. Tumour-associated myeloid cells (TAMCs) include monocytes, tumour-associated macrophages (TAMs), myeloid-derived suppressor cells (MDSCs), dendritic cells (DCs), and granulocytes. Single-cell profiling revealed heterogeneous TAMCs composition, sub-types, and transcriptomic signatures across 15 human cancer types. We systematically reviewed the biophysical heterogeneity of TAMC composition and pro/anti-tumoral and immuno-suppressive/stimulating properties of myeloid-derived microenvironments. We also summarised comprehensive clinical strategies to overcome resistance to immunotherapy from three dimensions: targeting TAMCs, reversing physical abnormalities, utilising nanomedicines, and finally, put forward futuristic perspectives for scientific and clinical research.

Reprogramming the Canine Glioma Microenvironment with Tumor Vaccination plus Oral Losartan and Propranolol Induces Objective Responses

Purpose

Malignant gliomas have a highly immune suppressive tumor microenvironment (TME) which renders them largely unresponsive to conventional therapeutics. Therefore, the present study evaluated a therapeutic protocol designed overcome the immune barrier by combining myeloid cell targeted immunotherapy with tumor vaccination.

Experimental Design

We utilized a spontaneously occurring canine glioma model to investigate an oral TME modifying immunotherapy in conjunction with cancer stem cell (CSC) vaccination. Dogs were treated daily with losartan (monocyte migration inhibitor) and propranolol (myeloid-derived suppressor cell depleting agent) plus anti-CSC vaccination on a bi-weekly then monthly schedule. Tumor volume was monitored by MRI and correlated with patient immune responses.

Results

Ten dogs with histologically confirmed gliomas were enrolled into a prospective, open-label clinical trial to evaluate the immunotherapy protocol. Partial tumor regression was observed in 2 dogs, while 6 dogs experienced stable disease, for an overall clinical benefit rate of 80%. Overall survival times (median = 351 days) and progression-free intervals (median = 163 days) were comparable to prior studies evaluating surgical debulking followed by immunotherapy. Dogs with detectable anti-CSC antibody responses had an increased overall survival time relative to dogs that did not generate antibody responses (vaccine responder MST = 500 days; vaccine non-responder MST = 218 days; p = 0.02).

Conclusions

These findings suggest that combining myeloid cell targeted oral immunotherapy with tumor vaccination can generate objective tumor responses, even in the absence of conventional therapy. Overall, this approach has promise as a readily implemented therapeutic strategy for use in brain cancer patients.

Synergy of Losartan and chemotherapy for patients with cholangiocarcinoma: A propensity score-matched analysis

Background

Cholangiocarcinoma (CCA) is a malignant tumor originating from bile duct epithelial cells that no obvious clinical symptoms and specific clinical manifestations are shown in the early stage of CCA.

Methods

Propensity score matching (PSM) is a quasi-experimental method in which this study used. Patients were enrolled from Department of General surgery, First Affiliated Hospital of Jinzhou Medical University from March 1, 2010, to December 30, 2019. Totally 170 patients with CCA were enrolled in this study.

Results

We performed a 1:2 PSM study and found that patients with losartan group showed both comparable median OS (overall survival) and TTR (time to recurrence) to those in the patients without losartan group before PSM. However, after matching, patients with losartan group showed favorable median OS and TTR than those in the patients without losartan group. Then we performed Cox proportional hazards models and found that patients with losartan was an independent factor after multivariable analysis for patients with CCA. Furtherly, we sequenced serial cfDNA were performed in 10 patients with losartan and 9 patients without losartan who received adjuvant chemotherapy after tumor resection. These results showed that the treatment of losartan was related with tumor microenvironment and could be potentially useful to combine the immunotherapy for patients with CCA.

Conclusion

In conclusion, this study demonstrated that the treatment of losartan could increase the efficacy of adjuvant chemotherapy and identified as an independent survival predictor for patients with CCA. Moreover, losartan could be potentially useful to combine the immunotherapy for patients with CCA.

Polymeric micelles effectively reprogram the tumor microenvironment to potentiate nano-immunotherapy in mouse breast cancer models

Nano-immunotherapy improves breast cancer outcomes but not all patients respond and none are cured. To improve efficacy, research focuses on drugs that reprogram cancer-associated fibroblasts (CAFs) to improve therapeutic delivery and immunostimulation. These drugs, however, have a narrow therapeutic window and cause adverse effects. Developing strategies that increase CAF-reprogramming while limiting adverse effects is urgent. Here, taking advantage of the CAF-reprogramming capabilities of tranilast, we developed tranilast-loaded micelles. Strikingly, a 100-fold reduced dose of tranilast-micelles induces superior reprogramming compared to free drug owing to enhanced intratumoral accumulation and cancer-associated fibroblast uptake. Combination of tranilast-micelles and epirubicin-micelles or Doxil with immunotherapy increases T-cell infiltration, resulting in cures and immunological memory in mice bearing immunotherapy-resistant breast cancer. Furthermore, shear wave elastography (SWE) is able to monitor reduced tumor stiffness caused by tranilast-micelles and predict response to nano-immunotherapy. Micellar encapsulation is a promising strategy for TME-reprogramming and SWE is a potential biomarker of response.

Assessment of Caregivers' Burden When Caring for Patients With Pancreatic and Periampullary Cancer

BACKGROUND

Family and other unpaid caregivers play an active role in the recovery of individuals with pancreatic and periampullary cancer after pancreatectomy. However, little is known about caregivers' experiences and how to better support them.

METHODS

Caregivers accompanying patients to 1-month postpancreatectomy visits at 3 hospitals completed an electronic survey between November 2018 and February 2020. We examine measures of absenteeism and work productivity loss among the subset of caregivers who reported working for pay and comparatively assess caregiver experiences by employment status. All analyses were performed as 2-sided tests.

RESULTS

Of 265 caregivers approached for study participation, 240 (90.6%) enrolled. Caregivers were primarily female (70.8% female, 29.2% male) and spouses (58.3%) or adult children (25.8%) of patients, with a median age of 60 years. Of the 240 caregivers included in the study, 107 (44.6%) worked for pay. Nearly half (44.4%) of working caregivers reported being absent from work because of caregiving amounting to a 14% loss in work hours. While at work, 58.9% of working caregivers reported increased work difficulty as a result of caregiving. Taken together, an estimated 59.7% loss in work productivity was experienced because of caregiving in the month following pancreatectomy. After adjustment for sociodemographic factors, working (vs nonworking) caregivers reported increased financial (odds ratio [OR] = 2.32; P = .04) and emotional (OR = 1.93; P = .04) difficulties and daily activity restrictions (OR = 1.85; P = .048).

CONCLUSIONS

Working caregivers of patients with pancreatic and periampullary cancer experience negative impacts on work and productivity, and caregiving-related financial and emotional difficulties may be amplified. This study highlights the need for workplace policies to support unpaid cancer caregiving.

Prospective Phase II Trials Validate the Effect of Neoadjuvant Chemotherapy on Pattern of Recurrence in Pancreatic Adenocarcinoma

OBJECTIVE

The objective of this study was to characterize the patterns of first recurrence after curative-intent resection for pancreatic adenocarcinoma (PDAC).

SUMMARY OF BACKGROUND DATA

We evaluated the first site of recurrence after neoadjuvant treatment as locoregional (LR) or distant metastasis (DM). To validate our findings, we evaluated the pattern from 2 phase II clinical trials evaluating neoadjuvant chemotherapy (NAC) in PDAC.

METHODS

We identified site of first recurrence from a retrospective cohort of patients from 2011 to 2017 treated with NAC followed by chemoradiation and then an operation or an operation first followed by adjuvant therapy, and 2 separate prospective cohorts of patients derived from 2 phase II clinical trials evaluating patients treated with NAC in borderline-resectable and locally advanced PDAC.

RESULTS

In the retrospective cohorts, 160 out of 285 patients (56.1%) recurred after a median disease-free survival (mDFS) of 17.2 months. The pattern of recurrence was DM in 81.9% of patients, versus LR in 11.1%. This pattern was consistent in patients treated with upfront resection and adjuvant chemotherapy (DM 83.0%, LR 16.9%) regardless of margin-involvement (DM 80.1%, LR 19.4%). The use of NAC did not alter pattern of recurrence; 81.7% had DM and 18.3% had LR. This pattern also remained consistent regardless of margin-involvement (DM 94.1%, LR 5.9%). In the Phase II borderline-resectable trial (NCI# 01591733) cohort of 32 patients, the mDFS was 34.2 months. Pattern of recurrence remained predominantly DM (88.9%) versus LR (11.1%). In the Phase II locally-advanced trial (NCI# 01821729) cohort of 34 patients, the mDFS was 30.7 months. Although there was a higher rate of local recurrence in this cohort, pattern of first recurrence remained predominantly DM (66.6%) versus LR (33.3%) and remained consistent independent of margin-status.

CONCLUSIONS

The pattern of recurrence in PDAC is predominantly DM rather than LR, and is consistent regardless of the use of NAC and margin involvement.

The Effects of Radiotherapy on Pancreatic Ductal Adenocarcinoma in Patients with Liver Metastases

BACKGROUND

While radiotherapy has been studied in the treatment of locally advanced pancreatic ductal adenocarcinoma (PDAC), few studies have analyzed the effects of radiotherapy on PDAC in patients with liver metastases. This study aimed to determine whether PDAC patients with liver metastases have improved survival after radiotherapy treatment.

METHODS

The data of 8535 patients who were diagnosed with PDAC with liver metastases between 2010 and 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Survival analysis and Cox proportional hazards regression analysis of cancer-specific mortality and overall survival were performed, and propensity score matching (PSM) was used to reduce selection bias.

RESULTS

After PSM, the median overall survival (mOS) and median cancer-specific survival (mCSS) in the radiotherapy group were longer than those in the nonradiotherapy group (OS: 6 months vs. 4 months; mCSS: 6 months vs. 5 months, both p < 0.05), respectively. The multivariate analysis showed that cancer-specific mortality rates were higher in the nonradiotherapy group than in the radiotherapy group (HR: 1.174, 95% CI: 1.035-1.333, p = 0.013). The Cox regression analysis according to subgroups showed that the survival benefits (OS and CSS) of radiotherapy were more significant in patients with tumor sizes greater than 4 cm (both p < 0.05).

CONCLUSIONS

PDAC patients with liver metastases, particularly those with tumor sizes greater than 4 cm, have improved cancer-specific survival (CSS) rates after receiving radiotherapy.

Personalized pancreatic cancer therapy: from the perspective of mRNA vaccine

Pancreatic cancer is characterized by inter-tumoral and intra-tumoral heterogeneity, especially in genetic alteration and microenvironment. Conventional therapeutic strategies for pancreatic cancer usually suffer resistance, highlighting the necessity for personalized precise treatment. Cancer vaccines have become promising alternatives for pancreatic cancer treatment because of their multifaceted advantages including multiple targeting, minimal nonspecific effects, broad therapeutic window, low toxicity, and induction of persistent immunological memory. Multiple conventional vaccines based on the cells, microorganisms, exosomes, proteins, peptides, or DNA against pancreatic cancer have been developed; however, their overall efficacy remains unsatisfactory. Compared with these vaccine modalities, messager RNA (mRNA)-based vaccines offer technical and conceptional advances in personalized precise treatment, and thus represent a potentially cutting-edge option in novel therapeutic approaches for pancreatic cancer. This review summarizes the current progress on pancreatic cancer vaccines, highlights the superiority of mRNA vaccines over other conventional vaccines, and proposes the viable tactic for designing and applying personalized mRNA vaccines for the precise treatment of pancreatic cancer.

Supportive Oncology Care at Home Intervention for Patients With Pancreatic Cancer

PURPOSE

We sought to determine the feasibility of delivering a Supportive Oncology Care at Home intervention among patients with pancreatic cancer.

METHODS

We prospectively enrolled patients with pancreatic cancer from a parent trial of neoadjuvant fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFIRINOX). The intervention entailed (1) remote monitoring of patient-reported symptoms, vital signs, and body weight; (2) a hospital-at-home care model; and (3) structured communication with the oncology team. We defined the intervention as feasible if ≥ 60% of patients enrolled in the study and ≥ 60% completed the daily assessments within the first 2-weeks of enrollment. We determined rates of treatment delays, urgent clinic visits, emergency department visits, and hospitalizations among those who did (n = 20) and did not (n = 24) receive Supportive Oncology Care at Home from the parent trial.

RESULTS

From January 2019 to September 2020, we enrolled 80.8% (21/26) of potentially eligible patients. One patient became ineligible following consent because of moving out of state, resulting in 20 participants (median age = 67 years). In the first 2 weeks of enrollment, 65.0% of participants completed all daily assessments. Overall, patients reported 96.1% of daily symptoms, 96.1% of daily vital signs, and 92.5% of weekly body weights. Patients receiving the intervention had lower rates of treatment delays (55.0% v 75.0%), urgent clinic visits (10.0% v 25.0%), and emergency department visits/hospitalizations (45.0% v 62.5%) compared with those not receiving the intervention from the same parent trial.

CONCLUSION

Findings demonstrate the feasibility and acceptability of a Supportive Oncology Care at Home intervention. Future work will investigate the efficacy of this intervention for decreasing health care use and improving patient outcomes.

Defining the Optimal Duration of Neoadjuvant Therapy for Pancreatic Ductal Adenocarcinoma: Time for a Personalized Approach?

ABSTRACT

Despite recent advances, pancreatic ductal adenocarcinoma (PDAC) continues to be associated with dismal outcomes, with a cure evading most patients. While historic treatment for PDAC has been surgical resection followed by 6 months of adjuvant therapy, there has been a recent shift toward neoadjuvant treatment (NAT). Several considerations support this approach, including the characteristic early systemic spread of PDAC, and the morbidity often surrounding pancreatic resection, which can delay recovery and preclude patients from starting adjuvant treatment. The addition of NAT has been suggested to improve margin-negative resection rates, decrease lymph node positivity, and potentially translate to improved survival. Conversely, complications and disease progression can occur during preoperative treatment, potentially eliminating the chance of curative resection. As NAT utilization has increased, treatment durations have been found to vary widely between institutions with an optimal duration remaining undefined. In this review, we assess the existing literature on NAT for PDAC, reviewing treatment durations reported across retrospective case series and prospective clinical trials to establish currently used approaches and seek the optimal duration. We also analyze markers of treatment response and review the potential for personalized approaches that may help clarify this important treatment question and move NAT toward a more standardized approach.

Development and validation of the Massachusetts General Hospital/Memorial Sloan Kettering nomogram to predict overall survival of resected patients with pancreatic ductal adenocarcinoma treated with neoadjuvant therapy

BACKGROUND

Prognostication in patients undergoing resection for pancreatic ductal adenocarcinoma following neoadjuvant therapy remains challenging. In this study, we aimed to develop and validate a nomogram for the prediction of overall survival of these patients.

METHODS

Patients who underwent neoadjuvant therapy followed by surgical resection at the Massachusetts General Hospital were analyzed (training cohort). Patients from Memorial Sloan Kettering were included as a validation cohort. A nomogram to predict overall survival was designed, trained, and subjected to internal (bootstrap) validation.

RESULTS

A total of 325 patients were identified from Massachusetts General Hospital. Multivariable Cox regression analysis demonstrated that age (hazard ratio 1.828, 95% confidence interval 1.251-2.246; P = .007), serum carbohydrate antigen 19-9 ≥ 37 U/mL (HR 1.602, 95% confidence interval 1.187-3.258; P = .015), tumor size (hazard ratio 2.278, 95% confidence interval 1.405-4.368; P = .003), nodal status (hazard ratio 1.309, 95% confidence interval 1.108-2.439; P = .032), and R1 tumor resection (hazard ratio 1.481, 95% confidence interval 1.049-2.091; P = .026) were independent factors associated with overall survival. A nomogram that incorporated these significant prognostic factors was established. The calibration plots demonstrated high concordance between predictive nomogram values and actual overall survival for 1-year, 3-year, and 5-year overall survival. The model demonstrated excellent discriminatory power in both the Massachusetts General Hospital and Memorial Sloan Kettering cohorts, with adjusted Harrel's concordance index values of 0.729 and 0.712, respectively.

CONCLUSION

In this report, we established and validated a novel nomogram for predicting the survival of patients who underwent neoadjuvant therapy followed by pancreatectomy. This model allows clinicians to better estimate the survival of these specific patients.

Endothelin-axis antagonism enhances tumor perfusion in pancreatic cancer

Delivery of therapeutic agents in pancreatic cancer (PC) is impaired due to its hypovascular and desmoplastic tumor microenvironment. The Endothelin (ET)-axis is the major regulator of vasomotor tone under physiological conditions and is highly upregulated in multiple cancers. We investigated the effect of dual endothelin receptor antagonist bosentan on perfusion and macromolecular transport in a PC cell-fibroblast co-implantation tumor model using Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI). Following bosentan treatment, the contrast enhancement ratio and wash-in rates in tumors were two- and nine times higher, respectively, compared to the controls, whereas the time to peak was significantly shorter (7.29 ± 1.29 min v/s 22.08 ± 5.88 min; p = 0.04). Importantly, these effects were tumor selective as the magnitudes of change for these parameters were much lower in muscles. Bosentan treatment also reduced desmoplasia and improved intratumoral distribution of high molecular weight FITC-dextran. Overall, these findings support that targeting the ET-axis can serve as a potential strategy to selectively enhance tumor perfusion and improve the delivery of therapeutic agents in pancreatic tumors.

Case report: Two PD-L1 positive unresectable advanced pancreatic carcinoma patients with microsatellite stability achieved R0 resection after PD-1 antibody plus chemotherapy as a successful downstaging therapy: A report of two cases

Background

Nonobvious early symptoms are a prominent characteristic of pancreatic cancer, resulting in only 20% of patients having resectable tumors at the time of diagnosis. The optimal management of unresectable advanced pancreatic cancer (UAPC) remains an open research question. In this study, the tumors shrank significantly after PD-1 antibody combined with chemotherapy in two UAPC patients, and both have achieved R0 (pathologically negative margin) resection and survival to date.

Case presentation

Case 1: A 53-year-old man was diagnosed with pancreatic adenocarcinoma (Stage III). He received six cycles of PD-1 antibody plus chemotherapy as the first-line treatment. The tumor was reduced from 11.8×8.8 cm to “0” (the pancreatic head was normal as shown by enhanced computed tomography, ECT) after preoperative neoadjuvant therapy (PNT) and the adverse effects were tolerable. The patient underwent radical surgery and achieved R0 resection. Case 2: A 43-year-old man diagnosed with pancreatic adenocarcinoma with liver metastasis (Stage IV) received three cycles of PD-1 antibody combined with chemotherapy. The tumor was reduced from 5.2×3.9 cm to 2.4×2.3 cm with no side effects. The patient also underwent radical surgery and achieved R0 resection.

Conclusion

PD-1 antibody plus a chemotherapy regimen resulted in a surprising curative effect and safety in two patients with UAPC, which may portend an improvement in pancreatic carcinoma treatment. We may have a way for UAPC patients to obtain radical treatment and gain long-term survival. Two PD-L1 positive UAPC patients with microsatellite stability (MSS) enlighten us to have a more comprehensive understanding of the prediction of immunotherapy.

Treatment-associated remodeling of the pancreatic cancer endothelium at single-cell resolution

Pancreatic ductal adenocarcinoma (PDAC) is one of the most treatment refractory and lethal malignancies. The diversity of endothelial cell (EC) lineages in the tumor microenvironment (TME) impacts the efficacy of antineoplastic therapies, which in turn remodel EC states and distributions. Here, we present a single-cell resolution framework of diverse EC lineages in the PDAC TME in the context of neoadjuvant chemotherapy, radiotherapy, and losartan. We analyzed a custom single-nucleus RNA-seq dataset derived from 37 primary PDAC specimens (18 untreated, 14 neoadjuvant FOLFIRINOX + chemoradiotherapy, 5 neoadjuvant FOLFIRINOX + chemoradiotherapy + losartan). A single-nucleus transcriptome analysis of 15,185 EC profiles revealed two state programs (ribosomal, cycling), four lineage programs (capillary, arterial, venous, lymphatic), and one program that did not overlap significantly with prior signatures but was enriched in pathways involved in vasculogenesis, stem-like state, response to wounding and hypoxia, and endothelial-to-mesenchymal transition (reactive EndMT). A bulk transcriptome analysis of two independent cohorts (n = 269 patients) revealed that the lymphatic and reactive EndMT lineage programs were significantly associated with poor clinical outcomes. While losartan and proton therapy were associated with reduced lymphatic ECs, these therapies also correlated with an increase in reactive EndMT. Thus, the development and inclusion of EndMT-inhibiting drugs (e.g., nintedanib) to a neoadjuvant chemoradiotherapy regimen featuring losartan and/or proton therapy may be most effective in depleting both lymphatic and reactive EndMT populations and potentially improving patient outcomes.

Collagenase-Loaded H-TiO2 Nanoparticles Enhance Ultrasound Imaging-Guided Sonodynamic Therapy in a Pancreatic Carcinoma Xenograft Model via Digesting Stromal Barriers

Sonodynamic therapy (SDT), a noninvasive therapy that relies on sonosensitizers and generates reactive oxygen species (ROS), has attracted considerable attention in the treatment of pancreatic cancer. However, being surrounded by dense stromal barriers, pancreatic cancer exhibits high interstitial fluid pressure (IFP) and hypoxia in the tumor microenvironment (TME), resulting in poor SDT efficacy. Collagenase-loaded hollow TiO₂ (Col-H-TiO₂) nanoparticles (NPs) capable of degrading stromal barriers and producing sufficient ROS production were synthesized in this study. After administration of NPs in the patient-derived xenograft (PDX) model, ultrasonic irradiation-released collagenase degraded tumor matrix fibers, decreased intratumoral IFP, and enhanced the penetration and retention of NPs within tumor tissues. Moreover, the NPs accumulated within the tumor not only generate abundant ROS under the influence of ultrasound irradiation but also improve intratumoral ultrasound signal, providing ultrasonic imaging-guided highly effective SDT for pancreatic cancer. In conclusion, this research improves the SDT technique and enhances the visualization of pancreatic cancer by remodeling the TME and is a promising strategy for further clinical applications.

The recent advances of cancer associated fibroblasts in cancer progression and therapy

As an abundant component of tumor microenvironment, cancer-associated fibroblasts (CAFs) are heterogeneous cell populations that play important roles in tumor development, progression and therapeutic resistance. Multiple sources of cells can be recruited and educated to become CAFs, such as fibroblasts, mesenchymal stem cells and adipocytes, which may explain the phenotypic and functional heterogeneity of CAFs. It is widely believed that CAFs regulate tumor progression by remodeling extracellular matrix, promoting angiogenesis, and releasing soluble cytokines, making them a promising cancer therapy target. In this review, we discussed about the origin, subpopulation, and functional heterogeneity of CAFs, with particular attention to recent research advances and clinical therapeutic potential of CAFs in cancer.

Neoadjuvant therapy in pancreatic cancer: a review and update on recent trials

PURPOSE OF REVIEW

Neoadjuvant therapy (NAT) has been enthusiastically embraced for patients with operable pancreatic cancer (PDAC) in hopes of improving survival. However, the rapid integration of clinical trial data has made it difficult to discern optimal treatment strategies. The goal of this review is to summarize notable recent trials and their contributions to the field.

RECENT FINDINGS

The results of ESPAC-5F, NEOLAP-AIO-PAK-0113, SWOG1505, PREOPANC, HyperAcutePancreas, and ALLIANCE A021501 are reviewed in detail. These studies sequentially evaluate the different neoadjuvant treatment strategies, use of neoadjuvant chemoradiation, and immunotherapy in resectable, borderline-resectable, and locally advanced PDAC. Resection rate ranged from 24.4 to 95.7% (median 64.9%). These trials demonstrate median survival ranging from 14.9 to 41.0 months with progression-free survival ranging from 7.7 to 24.2 months. Survival results may be confounded by ability to reach resection, use of modern chemotherapy vs. gemcitabine monotherapy, and inclusion of locally advanced PDAC. Several upcoming trials will directly examine efficacy of NAT vs. adjuvant therapy, chemoradiation in the NAT setting, and molecular testing-driven chemotherapy selection.

SUMMARY

NAT is associated with improved survival for patients with borderline resectable PDAC but broader efficacy for resectable PDAC and optimal treatment strategy have yet to be defined.

Reversal of pancreatic desmoplasia by a tumour stroma-targeted nitric oxide nanogel overcomes TRAIL resistance in pancreatic tumours

OBJECTIVE

Stromal barriers, such as the abundant desmoplastic stroma that is characteristic of pancreatic ductal adenocarcinoma (PDAC), can block the delivery and decrease the tumour-penetrating ability of therapeutics such as tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), which can selectively induce cancer cell apoptosis. This study aimed to develop a TRAIL-based nanotherapy that not only eliminated the extracellular matrix barrier to increase TRAIL delivery into tumours but also blocked antiapoptotic mechanisms to overcome TRAIL resistance in PDAC.

DESIGN

Nitric oxide (NO) plays a role in preventing tissue desmoplasia and could thus be delivered to disrupt the stromal barrier and improve TRAIL delivery in PDAC. We applied an in vitro-in vivo combinatorial phage display technique to identify novel peptide ligands to target the desmoplastic stroma in both murine and human orthotopic PDAC. We then constructed a stroma-targeted nanogel modified with phage display-identified tumour stroma-targeting peptides to co-deliver NO and TRAIL to PDAC and examined the anticancer effect in three-dimensional spheroid cultures in vitro and in orthotopic PDAC models in vivo.

RESULTS

The delivery of NO to the PDAC tumour stroma resulted in reprogramming of activated pancreatic stellate cells, alleviation of tumour desmoplasia and downregulation of antiapoptotic BCL-2 protein expression, thereby facilitating tumour penetration by TRAIL and substantially enhancing the antitumour efficacy of TRAIL therapy.

CONCLUSION

The co-delivery of TRAIL and NO by a stroma-targeted nanogel that remodels the fibrotic tumour microenvironment and suppresses tumour growth has the potential to be translated into a safe and promising treatment for PDAC.

Combination immunotherapy for pancreatic cancer: challenges and future considerations

INTRODUCTION

: Immune checkpoint inhibitors (ICI) have not yielded significant efficacy in pancreatic ductal adenocarcinoma (PDA), despite the role of the innate and adaptive immune systems on progression and survival. However, recently identified pathways have identified new targets and generated promising clinical investigations into promoting an effective immune-mediated antitumor response in PDA.

AREAS COVERED

: We review biological mechanisms associated with immunotherapy resistance and outline strategies for therapeutic combinations with established and novel therapies in PDA.

EXPERT OPINION

: Pancreatic cancers rarely benefits from treatment with ICI due to an immunosuppressive tumor microenvironment (TME). New understandings of factors associated with the suppressive TME, include low and poor quality neoantigens, constrained effector T cells infiltration, and the presence of a dense, suppressive myeloid cell population. These findings have been translated into new clinical investigations evaluating novel therapies in combination with ICI and/or standard systemic chemotherapy and radiotherapy. The epithelial, immune, and stromal compartments are intricately related in PDA, and the framework for successful targeting of this disease requires a comprehensive and personalized approach.

Clinical Strategies Targeting the Tumor Microenvironment of Pancreatic Ductal Adenocarcinoma

Pancreatic cancer has a complex tumor microenvironment which engages in extensive crosstalk between cancer cells, cancer-associated fibroblasts, and immune cells. Many of these interactions contribute to tumor resistance to anti-cancer therapies. Here, new therapeutic strategies designed to modulate the cancer-associated fibroblast and immune compartments of pancreatic ductal adenocarcinomas are described and clinical trials of novel therapeutics are discussed. Continued advances in our understanding of the pancreatic cancer tumor microenvironment are generating stromal and immune-modulating therapeutics that may improve patient responses to anti-tumor treatment.

Study protocol for a prospective, open-label, single-arm, phase II study on the combination of tislelizumab, nab-paclitaxel, gemcitabine, and concurrent radiotherapy as the induction therapy for patients with locally advanced and borderline resectable pancreatic cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a fatal malignancy with a low resection rate. Chemotherapy and radiotherapy (RT) are the main treatment approaches for patients with advanced pancreatic cancer, and neoadjuvant chemoradiotherapy is considered a promising strategy to increase the resection rate. Recently, immune checkpoint inhibitor (ICI) therapy has shown remarkable efficacy in several cancers. Therefore, the combination of ICI, chemotherapy, and concurrent radiotherapy is promising for patients with potentially resectable pancreatic cancer, mainly referring to locally advanced (LAPC) and borderline resectable pancreatic cancer (BRPC), to increase the chances of conversion to surgical resectability and prolong survival. This study aims to introduce the design of a clinical trial.

METHODS

This is an open-label, single-arm, and single-center phase II trial. Patients with pathologically and radiographically confirmed LAPC or BRPC without prior anti-cancer treatment or severe morbidities will be enrolled. All patients will receive induction therapy and will be further evaluated by the Multiple Disciplinary Team (MDT) for the possibility of surgery. The induction therapy consists of up to four cycles of gemcitabine 1,000 mg/m2 and nab-paclitaxel 125 mg/m2 via intravenous (IV) infusion on days 1 and 8, along with tislelizumab (a PD-1 monoclonal antibody) 200 mg administered through IV infusion on day 1 every 3 weeks, concurrently with stereotactic body radiation therapy (SBRT) during the third cycle of treatment. After surgery, patients without progression will receive another two to four cycles of adjuvant therapy with gemcitabine, nab-paclitaxel, and tislelizumab. The primary objectives are objective response rate (ORR) and the R0 resection rate. The secondary objectives are median overall survival (mOS), median progression free survival (mPFS), disease control rate (DCR), pathological grade of tumor tissue after therapy, and adverse reactions. Besides, we expect to explore the value of circulating tumor DNA (ctDNA) in predicting tumor response to induction therapy and survival outcome of patients.

DISCUSSION

This is a protocol for a clinical trial that attempts to evaluate the safety and efficacy of the combination of anti-PD-1 antibody plus chemotherapy and radiotherapy as the induction therapy for LAPC and BRPC. The results of this phase II study will provide evidence for the clinical practice of this modality.

CLINICAL TRIAL REGISTRATION

http://www.chictr.org.cn/edit.aspx?pid=53720&htm=4, identifier ChiCTR2000032955.

Cancer-Associated Fibroblasts: Tumorigenicity and Targeting for Cancer Therapy

Simple Summary

Cancer-associated fibroblasts (CAFs) are found in the tumor microenvironment and exhibit several protumorigenic functions. Preclinical studies suggest that CAFs can be reduced, eliminated, or reprogrammed; however, clinical translation has not yet occurred. A better understanding of these cells and their functions will undoubtedly improve cancer treatments. In this review, we summarize current research, highlight major challenges, and discuss future opportunities for improving our knowledge of CAF biology and targeting.

Abstract

Cancer-associated fibroblasts (CAFs) are a heterogenous group of activated fibroblasts and a major component of the tumor stroma. CAFs may be derived from fibroblasts, epithelial cells, endothelial cells, cancer stem cells, adipocytes, pericytes, or stellate cells. These complex origins may underlie their functional diversity, which includes pro-tumorigenic roles in extracellular matrix remodeling, the suppression of anti-tumor immunity, and resistance to cancer therapy. Several methods for targeting CAFs to inhibit tumor progression and enhance anti-tumor immunity have recently been reported. While preclinical studies have shown promise, to date they have been unsuccessful in human clinical trials against melanoma, breast cancer, pancreas cancer, and colorectal cancers. This review summarizes recent and major advances in CAF-targeting therapies, including DNA-based vaccines, anti-CAF CAR-T cells, and modifying and reprogramming CAF functions. The challenges in developing effective anti-CAF treatment are highlighted, which include CAF heterogeneity and plasticity, the lack of specific target markers for CAFs, the limitations in animal models recapitulating the human cancer microenvironment, and the undesirable off-target and systemic side effects. Overcoming these challenges and expanding our understanding of the basic biology of CAFs is necessary for making progress towards safe and effective therapeutic strategies against cancers in human patients.

Impact of renin-angiotensin system inhibitors on outcomes in patients with metastatic renal cell carcinoma treated with immune-checkpoint inhibitors

BACKGROUND

Renin-angiotensin system inhibitors (RASi) have been shown to improve outcomes in studies of multiple malignancies by effects on the tumor microenvironment to enhance the immune repertoire and improve drug delivery. Repurposing RASi to treat metastatic renal cell carcinoma (mRCC) in combination with immune-checkpoint inhibitors (ICI) may improve survival coupled with tolerability and cost efficacy. We evaluated the impact of RASi on outcomes in mRCC patients receiving ICI.

METHODS

This multicenter, retrospective cohort study included mRCC patients treated with ICI with or without RASi. The patients from Dana-Farber Cancer Institute (DFCI) were used as a discovery cohort, and the patients from University of California San Diego (UCSD) were used for validation. Receipt of an ICI (PD1/L1 and/or CTLA-4 inhibitors) was required. RASi use was defined as receipt of a RASi at baseline and for a minimum of 30 days after ICI initiation. For both the discovery and validation cohorts, the primary outcome assessed was overall survival (OS) and the secondary endpoints were time-to-treatment failure (TTF), and objective response rate (ORR).

RESULTS

Overall, 229 patients who received an ICI were included: 100 patients from DFCI and 129 patients from UCSD. Concomitant RASi were administered in 30 patients (30%) in the DFCI cohort and 59 (45%) in the UCSD cohort. Median age at ICI initiation was 62.5 years in both cohorts. Median follow-up was 3.8 [IQR 3-5.3] years in the DFCI cohort, and 2.3 [IQR 1.4-3.6] years in the UCSD cohort. In the DFCI cohort, RASi was significantly associated with longer OS (adjusted-HR 0.35 [95% CI, 0.17-0.70], P = .003) and TTF (adjusted-HR 0.57 [0.36-0.92], P = .02). In the validation cohort, RASi was associated with TTF (adjusted HR, 0.60 [0.39-0.92], P = .02) and not statistically associated with OS (adjusted-HR 0.60 [0.34-1.06], P = .07). The propensity analysis, matching 83 patients from both cohorts receiving RASi while on ICI with 83 who did not, showed that RASi significantly improved OS (HR 0.59 [0.37-0.95], P = .03) and TTF (HR 0.60 [0.43-0.85], P = .0034).

CONCLUSIONS

RASi was associated with improved OS and TTF in mRCC patients receiving ICI. This provides a rationale for prospective randomized studies combining ICI and RASi in mRCC patients.

Single-nucleus and spatial transcriptome profiling of pancreatic cancer identifies multicellular dynamics associated with neoadjuvant treatment

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal and treatment-refractory cancer. Molecular stratification in pancreatic cancer remains rudimentary and does not yet inform clinical management or therapeutic development. Here, we construct a high-resolution molecular landscape of the cellular subtypes and spatial communities that compose PDAC using single-nucleus RNA sequencing and whole-transcriptome digital spatial profiling (DSP) of 43 primary PDAC tumor specimens that either received neoadjuvant therapy or were treatment naive. We uncovered recurrent expression programs across malignant cells and fibroblasts, including a newly identified neural-like progenitor malignant cell program that was enriched after chemotherapy and radiotherapy and associated with poor prognosis in independent cohorts. Integrating spatial and cellular profiles revealed three multicellular communities with distinct contributions from malignant, fibroblast and immune subtypes: classical, squamoid-basaloid and treatment enriched. Our refined molecular and cellular taxonomy can provide a framework for stratification in clinical trials and serve as a roadmap for therapeutic targeting of specific cellular phenotypes and multicellular interactions.

Prognostic and predictive value of CA 19-9 in locally advanced pancreatic cancer treated with multiagent induction chemotherapy: results from a prospective, multicenter phase II trial (NEOLAP-AIO-PAK-0113)

BACKGROUND

The prognostic and predictive value of carbohydrate antigen 19-9 (CA 19-9) in locally advanced pancreatic cancer (LAPC) has not yet been defined from prospective randomized controlled trials (RCTs).

PATIENTS AND METHODS

A total of 165 LAPC patients were treated within the NEOLAP RCT for 16 weeks with multiagent induction chemotherapy [ICT; either nab-paclitaxel/gemcitabine alone or nab-paclitaxel/gemcitabine followed by FOLFIRINOX (combination of fluorouracil, leucovorin, irinotecan, and oxaliplatin)] followed by surgical exploration of all patients without evidence of disease progression. CA 19-9 was determined at baseline and after ICT and correlated with overall survival (OS) and secondary R0 resection rate.

RESULTS

From the NEOLAP study population (N = 165) 133 patients (81%) were evaluable for CA 19-9 at baseline and 81/88 patients (92%) for post-ICT CA 19-9 response. Median OS (mOS) in the CA 19-9 cohort (n = 133) was 16.2 months [95% confidence interval (CI) 13.0-19.4] and R0 resection (n = 31; 23%) was associated with a significant survival benefit [40.8 months (95% CI 21.7-59.8)], while R1 resected patients (n = 14; 11%) had no survival benefit [14.0 (95% CI 11.7-16.3) months, hazard ratio (HR) 0.27; P = 0.001]. After ICT most patients showed a CA 19-9 response (median change from baseline: -82%; relative decrease ≥55%: 83%; absolute decrease to ≤50 U/ml: 43%). Robust CA 19-9 response (decrease to ≤50U/ml) was significantly associated with mOS [27.8 (95% CI 18.4-37.2) versus 16.5 (95% CI 11.7-21.2) months, HR 0.49; P = 0.013], whereas CA 19-9 baseline levels were not prognostic for OS. Multivariate analysis demonstrated that a robust CA 19-9 response was an independent predictive factor for R0 resection. Using a CA 19-9 decrease to ≤61 U/ml as optimal cut-off (by receiver operating characteristic analysis) yielded 72% sensitivity and 62% specificity for successful R0 resection, whereas CA 19-9 nonresponders (<20% decrease or increase) had no chance for successful R0 resection.

CONCLUSIONS

CA 19-9 response after multiagent ICT provides relevant prognostic and predictive information and is useful in selecting LAPC patients for explorative surgery.

CLINICAL TRIAL NUMBER

ClinicalTrials.govNCT02125136; https://clinicaltrials.gov/ct2/show/NCT02125136; EudraCT 2013-004796-12; https://www.clinicaltrialsregister.eu/ctr-search/trial/2013-004796-12/results.

Do antihypertensive drugs really have antitumor effects? Baseline differences in hypertensive and non-hypertensive patients with advanced pancreatic cancer

Although the antitumor effects of antihypertensive drugs for patients with advanced pancreatic cancer (APC) have been investigated, their efficacy remains unclear. Previous studies suggest that hypertensive (HT) patients with APC are significantly older than non-HT patients with APC, and that other major baseline differences in patient characteristics which may affect prognosis exist between HT and non-HT patients. It is also possible that antihypertensive drugs lack antitumor activity. Therefore, we herein retrospectively investigated the baseline differences between HT and non-HT patients with APC. From January 2015 to April 2020, 56 patients with APC received nab-paclitaxel plus gemcitabine as first-line chemotherapy at Higashiosaka City Medical Center (Higashiosaka, Japan). Of these 56 patients, 30 were diagnosed with hypertension (HT group); the remaining 26 did not have hypertension (non-HT group). Differences between the two groups were compared and prognostic factors were evaluated. Patients in the HT group had significantly less sarcopenia, a significantly larger body mass index, were significantly older, and significantly more likely to have a regular doctor and primary site in the body and tail of the pancreas than those in the non-HT group. Although no significant difference was found in the treatment response, patients in the HT group were significantly more likely to move to second-line chemotherapy than those in the non-HT group. Survival curves showed that median overall survival (OS) in the HT group was significantly longer (10.5 months) than in the non-HT group (6.8 months, P = .04). Multivariate analysis did not identify the use of antihypertensive drugs as an independent prognostic factor of OS. We identified key baseline differences in the characteristics of APC patients with and without HT, suggesting that major selection bias could occur when investigating the efficacy of antihypertensive drugs in all populations. Therefore, it is possible that antihypertensive drugs lack antitumor activity. To determine the true efficacy of antihypertensive drugs for APC, HT, and non-HT patients in another population should be investigated, or a prospective, randomized, controlled trial conducted that is stratified by HT or non-HT status.

Comparative efficacy and safety of neoadjuvant radiotherapy for patients with borderline resectable, and locally advanced pancreatic ductal adenocarcinoma: a systematic review and network meta-analysis protocol

INTRODUCTION

The optimal dose and treatment modality of neoadjuvant radiotherapy applied for treating borderline resectable and locally advanced pancreatic ductal adenocarcinoma (PDAC) have been debated topics in oncology. The objective of the present network meta-analysis (NMA) is to study and compare the efficacy and safety of neoadjuvant radiotherapy comprehensively using different doses in patients with borderline resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC).

METHODS AND ANALYSIS

Four electronic databases, including PubMed, EMBASE, Cochrane library and Web of science, will be searched thoroughly to identify relevant studies published from 2006 to October 2020. Electronic searching by titles using neoadjuvant treatments for PDAC will be performed in the annual meetings of European Society of Medical Oncology and American Society of Clinical Oncology (2018-2020).

CLINICALTRIALS

gov will also be searched for grey literature. Two reviewers will perform search strategies and extract data independently. R0 resection rate and local control rate are defined as primary outcomes. Secondary outcomes include overall survival, disease-free survival and acute and late grade 3 and grade 4 toxicities. For randomised control trials, the risk of bias will be assessed using the Cochrane Risk of Bias Tool, while the risk of bias for non-randomised, observational studies will be evaluated using the Risk Of Bias In Non-randomised Studies-of Interventions. The quality of evidence will be evaluated using the version of Cochrane tool and Grades of Recommendation, Assessment, Development and Evaluation. Subgroup analysis and sensitivity analysis will be conducted in the present NMA.

ETHICS AND DISSEMINATION

This study will synthesise the evidence regarding dose schedule of neoadjuvant radiotherapy in patients with BRPC and LAPC. We hope the findings from this NMA will help clinicians and patients select the optimal modality and dose schedule of neoadjuvant radiotherapy with respect to patient-reported outcomes. As no primary data collection will be undertaken, no ethics approval is required. The results will be disseminated through peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42020222408.

The Desmoplastic Stroma of Pancreatic Cancer: Multilayered Levels of Heterogeneity, Clinical Significance, and Therapeutic Opportunities

Simple Summary

Pancreatic cancer is a highly malignant disease with treatment resistance to standardized chemotherapies. In addition, only a small fraction of patients with pancreatic cancer has, to date, actionable genetic aberrations, leading to a narrow therapeutic window for molecularly targeted therapies or immunotherapies. A lot of preclinical and translational studies are ongoing to discover potential vulnerabilities to treat pancreatic cancer. Histologically, human pancreatic cancer is characterized by abundant cancer-associated fibrotic stroma, called “desmoplastic stroma”. Recent technological advances have revealed that desmoplastic stroma in pancreatic cancer is much more complicated than previously thought, playing pleiotropic roles in manipulating tumor cell fate and anti-tumor immunity. Moreover, real-world specimen-based analyses of pancreatic cancer stroma have also uncovered spatial heterogeneity and an intertumoral variety associated with molecular alterations, clinicopathological factors, and patient outcomes. This review describes an overview of the current efforts in the field of pancreatic cancer stromal biology and discusses treatment opportunities of stroma-modifying therapies against this hard-to-treat cancer.

Abstract

Pancreatic cancer remains one of the most lethal malignancies and is becoming a dramatically increasing cause of cancer-related mortality worldwide. Abundant desmoplastic stroma is a histological hallmark of pancreatic ductal adenocarcinoma. Emerging evidence suggests a promising therapeutic effect of several stroma-modifying therapies that target desmoplastic stromal elements in the pancreatic cancer microenvironment. The evidence also unveils multifaceted roles of cancer-associated fibroblasts (CAFs) in manipulating pancreatic cancer progression, immunity, and chemotherapeutic response. Current state-of-the-art technologies, including single-cell transcriptomics and multiplexed tissue imaging techniques, have provided a more profound knowledge of CAF heterogeneity in real-world specimens from pancreatic cancer patients, as well as in genetically engineered mouse models. In this review, we describe recent advances in the understanding of the molecular pathology bases of pancreatic cancer desmoplastic stroma at multilayered levels of heterogeneity, namely, (1) variations in cellular and non-cellular members, including CAF subtypes and extracellular matrix (ECM) proteins; (2) geographical heterogeneity in relation to cell–cell interactions and signaling pathways at niche levels and spatial heterogeneity at locoregional levels or organ levels; and (3) intertumoral stromal heterogeneity at individual levels. This review further discusses the clinicopathological significance of desmoplastic stroma and the potential opportunities for stroma-targeted therapies against this lethal malignancy.

Current status and future perspectives of clinical research in pancreatic cancer: Establishment of evidence by science

Pancreatic cancer is one of the most aggressive diseases in the world due to a lack of early detection, leading to an overall 5-year survival of only 10%. In recent years, clinical trials targeted pancreatic cancer in efforts to improve survival. These studies introduce new technologies, concepts, and evidence which have instilled new optimism for improving prognosis. This review summarizes the current status of the recent (5-year) clinical trials and describes contemporary research on pancreatic cancer, including surgical technology, diagnostic skills, traditional chemoradiotherapy, neoadjuvant chemotherapy, immunotherapy, targeted therapy, and precision medicine. Then, the future trend and direction of clinical trials on pancreatic cancer are discussed.

Advanced iron oxide nanotheranostics for multimodal and precision treatment of pancreatic ductal adenocarcinoma

Despite current advances in new approaches for cancer detection and treatment, pancreatic cancer remains one of the most lethal cancer types. Difficult to detect early, aggressive tumor biology, and resistance to chemotherapy, radiotherapy, and immunotherapy result in a poor prognosis of pancreatic cancer patients with a 5-year survival of 10%. With advances in cancer nanotechnology, new imaging and drug delivery approaches that allow the development of multifunctional nanotheranostic agents offer opportunities for improving pancreatic cancer treatment using precision oncology. In this review, we will introduce potential applications of innovative theranostic strategies to address major challenges in the treatment of pancreatic cancer at different disease stages. Several important issues concerning targeted delivery of theranostic nanoparticles and tumor stromal barriers are discussed. We then focus on the development of a magnetic iron oxide nanoparticle platform for multimodal therapy of pancreatic cancer, including MRI monitoring targeted nanoparticle/drug delivery, therapeutic response, and tumor re-staging, activation of tumor immune response by immunoactivating nanoparticle and magnetic hyperthermia therapy, and intraoperative interventions for improving the outcome of targeted therapy. This article is categorized under: Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Diagnostic Tools > In Vivo Nanodiagnostics and Imaging.

Factors associated with inability to return to intended oncologic treatment in pancreatic cancer

BACKGROUND

Return to Intended Oncologic Treatment (RIOT) has been proposed as a quality metric in the care of cancer patients. We sought to define factors associated with inability to RIOT in Pancreatic Ductal Adenocarcinoma (PDAC) patients.

METHODS

The NCDB was queried for patients who underwent pancreaticoduodenectomy for pathologic stage IB, IIA, or IIB PDAC from 2010 to 2016. Multivariable binary logistic regression models identified factors associated with failure to RIOT, and Kaplan-Meier survival analysis and Cox multivariable regression models demonstrated the impact of failure to RIOT on survival.

RESULTS

Increasing age (p < .001), Hispanic race (p = .002), pathological stage IB (p = .004) and IIA (p = .001) as compared to IIB, increasing hospital stay (p < .001), and open surgical approach (p = .024) were associated with increased risk of inability to RIOT. Male sex (p < .001), Charlson-Deyo scores of 0 (p < .001) and 1 (p = .001) as compared to >2, negative surgical margins (p = .048), receiving care at academic institutions (p = .001), and increasing institutional case volume (p = .001) were associated with improved odds of RIOT.

CONCLUSIONS

Patient features can impact RIOT and should be considered when designing multi-modality treatment strategies.

Cancer-associated fibroblasts in pancreatic cancer: new subtypes, new markers, new targets

Cancer-associated fibroblasts (CAFs) have conflicting roles in the suppression and promotion of cancer. Current research focuses on targeting the undesirable properties of CAFs, while attempting to maintain tumour-suppressive roles. CAFs have been widely associated with primary or secondary therapeutic resistance, and strategies to modify CAF function have therefore largely focussed on their combination with existing therapies. Despite significant progress in preclinical studies, clinical translation of CAF targeted therapies has achieved limited success. Here we will review our emerging understanding of heterogeneous CAF populations in tumour biology and use examples from pancreatic ductal adenocarcinoma to explore why successful clinical targeting of protumourigenic CAF functions remains elusive. Single-cell technologies have allowed the identification of CAF subtypes with a differential impact on prognosis and response to therapy, but currently without clear consensus. Identification and pharmacological targeting of CAF subtypes associated with immunotherapy response offers new hope to expand clinical options for pancreatic cancer. Various CAF subtype markers may represent biomarkers for patient stratification, to obtain enhanced response with existing and emerging combinatorial therapeutic strategies. Thus, CAF subtyping is the next frontier in understanding and exploiting the tumour microenvironment for therapeutic benefit. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Enhanced Therapeutic Efficacy of Combining Losartan and Chemo-Immunotherapy for Triple Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a particularly aggressive subtype of breast cancer, which is relatively resistant to anti-programmed cell death-1 (α-PD1) therapy, characterized as non-immunogenic, dense stroma and accumulation of M2 tumor-associated macrophages (TAMs). Despite progress in strategies to deplete extracellular matrix (ECM) and enhance tumor-cell immunogenicity, the combinatorial anti-cancer effects with α-PD1 need to be explored. Here, we applied doxorubicin hydrochloride liposome (Dox-L) as immunogenic cell death (ICD)-inducing nano-chemotherapy and used losartan as stroma-depleting agent to improve α-PD1 efficacy (Losartan + Dox-L + α-PD1). The results showed that losartan could cause ECM reduction, facilitating enhanced delivery of Dox-L and further dendritic cell (DC) maturation. Additionally, losartan could also alleviate hypoxia for TNBC, thus reprogramming pro-cancer M2 TAMs to anti-cancer M1 TAMs, successfully overcoming immune-suppressive microenvironment. These modifications led to a significant increase in T cells’ infiltration and augmented anti-tumor immunity as exemplified by the notable reduction in tumor size and lung metastases. In summary, our findings support that combined treatment of losartan with Dox-L normalizes immunological-cold microenvironment, improves immuno-stimulation and optimizes the efficacy of TNBC immunotherapy. A novel combinational strategy with FDA-approved compounds proposed by the study may potentially be useful in TNBC clinical treatment.

Targeting Tumour-Associated Fibroblasts in Cancers

Tumours develop within complex tissue environments consisting of aberrant oncogenic cancer cells, diverse innate and adaptive immune cells, along with structural stromal cells, extracellular matrix and vascular networks, and many other cellular and non-cellular soluble constituents. Understanding the heterogeneity and the complex interplay between these cells remains a key barrier in treating tumours and cancers. The immune status of the pre-tumour and tumour milieu can dictate if the tumour microenvironment (TME) supports either a pro-malignancy or an anti-malignancy phenotype. Identification of the factors and cell types that regulate the dysfunction of the TME is crucial in order to understand and modulate the immune status of tumours. Among these cell types, tumour-associated fibroblasts are emerging as a major component of the TME that is often correlated with poor prognosis and therapy resistance, including immunotherapies. Thus, a deeper understanding of the complex roles of tumour-associated fibroblasts in regulating tumour immunity and cancer therapy could provide new insight into targeting the TME in various human cancers. In this review, we summarize recent studies investigating the role of immune and key stromal cells in regulating the immune status of the TME and discuss the therapeutic potential of targeting stromal cells, especially tumour-associated fibroblasts, within the TME as an adjuvant therapy to sensitize immunosuppressive tumours and prevent cancer progression, chemo-resistance and metastasis.

Towards Immunotherapy-Induced Normalization of the Tumor Microenvironment

Immunotherapies modulate the function of immune cells to eradicate cancer cells through various mechanisms. These therapies are successful across a spectrum of cancers, but they are curative only in a subset of patients. Indeed, a major obstacle to the success of immunotherapies is the immunosuppressive nature of the tumor microenvironment (TME), comprising the stromal component and immune infiltrate of tumors. Importantly, the TME in most solid cancers is characterized by sparsely perfused blood vessels resulting from so-called pathological angiogenesis. In brief, dysregulated development of new vessels results in leaky tumor blood vessels that inefficiently deliver oxygen and other nutrients. Moreover, the occurrence of dysregulated fibrosis around the lesion, known as pathological desmoplasia, further compresses tumor blood vessels and impairs blood flow. TME normalization is a clinically tested treatment strategy to reverse these tumor blood vessel abnormalities resulting in stimulated antitumor immunity and enhanced immunotherapy efficacy. TME normalization includes vascular normalization to reduce vessel leakiness and reprogramming of cancer-associated fibroblast to decompress vessels. How immunotherapies themselves normalize the TME is poorly understood. In this review, we summarize current concepts and progress in TME normalization. Then, we review observations of immunotherapy-induced TME normalization and discuss the considerations for combining vascular normalizing and immunotherapies. If TME could be more completely normalized, immunotherapies could be more effective in more patients.

Neoadjuvant Therapy for Pancreatic Ductal Adenocarcinoma: Where Do We Go?

The incidence of pancreatic ductal adenocarcinoma (PDAC) has been on the rise in recent years; however, its clinical diagnosis and treatment remain challenging. Although surgical resection remains the only chance for long-term patient survival, the likelihood of initial resectability is no higher than 20%. Neoadjuvant therapy (NAT) in PDAC aims to transform the proportion of inoperable PDACs into operable cases and reduce the likelihood of recurrence to improve overall survival. Ongoing phase 3 clinical trial aims to validate the role of NAT in PDAC therapy, including prolongation of survival, increased R0 resection, and a higher proportion of negative lymph nodes. Controversies surrounding the role of NAT in PDAC treatment include applicability to different stages of PDAC, chemotherapy regimens, radiation, duration of treatment, and assessment of effect. This review aims to summarize the current progress and controversies of NAT in PDAC.

Proton Therapy in the Management of Pancreatic Cancer

Radiation therapy plays a central role in the treatment of pancreatic cancer. While generally shown to be feasible, proton irradiation, particularly when an ablative dose is planned, remains a challenge, especially due to tumor motion and the proximity to organs at risk, like the stomach, duodenum, and bowel. Clinically, standard doses of proton radiation treatment have not been shown to be statistically different from photon radiation treatment in terms of oncologic outcomes and toxicity rates as per non-randomized comparative studies. Fractionation schedules and concurrent chemotherapy combinations are yet to be optimized for proton therapy and are the subject of ongoing trials.

Total neoadjuvant therapy for pancreatic adenocarcinoma increases probability for a complete pathologic response

BACKGROUND

Multiple neoadjuvant therapy protocols have been proposed in the treatment of pancreatic adenocarcinoma, including chemotherapy (CT), chemoradiation (CRT), and total neoadjuvant therapy (TNT), defined as a CT plus CRT. A pathologic complete response (pCR) can be achieved in a minority of cases. We hypothesize that TNT is more likely to confer pCR than other neoadjuvant therapies, which may improve overall survival (OS).

METHODS

A retrospective review of the National Cancer Database (NCDB) from 2006 to 2016 was performed, identifying patients who underwent any neoadjuvant therapy followed by definitive pancreatic resection for locally advanced or borderline resectable pancreatic adenocarcinoma. A pathologic complete response was defined as down-staging from any clinical stage to pathologic stage 0.

RESULTS

A total of 5402 patients who received neoadjuvant therapy followed by resection were identified. 177 patients (3.3%) achieved a pCR. Of the patients who achieved a pCR, 57 received CT, 41 CRT and 79 received TNT. On multivariate analysis, TNT was more likely to confer a pCR than CRT (OR 1.67, CI 1.13-2.46, p = 0.0103) or CT (OR 2.61, CI 1.83-3.71, p < 0.0001). Patients who achieved pCR had a significantly higher OS, with median survival of 64.9 months, compared to 21.6 months in patients who did not achieve pCR (p < 0.0001).

CONCLUSION

TNT may be more likely to achieve a pCR than CT or CRT. Patients who achieve a pCR have a significant OS benefit as compared to those who have residual disease. TNT should be considered for patients requiring neoadjuvant therapy, as it may increase the likelihood of achieving a pCR, thus potentially improving OS.

Results of a Phase II Study on the Use of Neoadjuvant Chemotherapy (FOLFIRINOX or GEM/nab-PTX) for Borderline-resectable Pancreatic Cancer (NUPAT-01)

OBJECTIVE

Given the frequent adverse events with multidrug chemotherapy, not only the survival benefit but also the feasibility of using neoadjuvant chemotherapy to treat pancreatic cancer need to be clarified.

SUMMARY OF BACKGROUND DATA

Although the development of multidrug chemotherapy regimens has improved the survival outcomes of patients with unresectable pancreatic cancer, the benefits of these treatments in the neo-adjuvant setting remain controversial.

METHODS

Patients with borderline-resectable pancreatic cancer were enrolled and randomly assigned to receive neoadjuvant chemotherapy with either FOLFIRINOX or gemcitabine with nab-paclitaxel (GEM/nab-PTX). After the completion of chemotherapy, patients underwent surgical resection when feasible. This study (NUPAT-01) was a randomized phase II trial, and the primary endpoint was the R0 resection rate.

RESULTS

Fifty-one patients were enrolled in this study [FOLFIRINOX (n = 26) and GEM/nab-PTX (n = 25)]. A total of 84.3% (n = 43/51) of the patients eventually underwent surgery, and R0 resection was achieved in 67.4% (n = 33/ 51) of the patients. Adverse events (grade >3) due to neoadjuvant treatment were observed in 45.1% of the patients (n = 23/51), and major surgical complications occurred in 30.0% (n = 13/43), with no mortality noted. The intention-to-treat analysis showed that the 3-year overall survival rate was 54.7%, with a median survival time of 39.4 months, and a significant difference in overall survival was not observed between the FOLFIRINOX and GEM/nab-PTX groups.

CONCLUSIONS

These results indicate that neoadjuvant chemotherapy with FOLFIRINOX or GEM/nab-PTX is feasible and well tolerated, achieving an R0 resection rate of 67.4%. The survival of patients was even found to be favorable in the intention-to-treat analysis.

Therapy resistance: opportunities created by adaptive responses to targeted therapies in cancer

Normal cells explore multiple states to survive stresses encountered during development and self-renewal as well as environmental stresses such as starvation, DNA damage, toxins or infection. Cancer cells co-opt normal stress mitigation pathways to survive stresses that accompany tumour initiation, progression, metastasis and immune evasion. Cancer therapies accentuate cancer cell stresses and invoke rapid non-genomic stress mitigation processes that maintain cell viability and thus represent key targetable resistance mechanisms. In this Review, we describe mechanisms by which tumour ecosystems, including cancer cells, immune cells and stroma, adapt to therapeutic stresses and describe three different approaches to exploit stress mitigation processes: (1) interdict stress mitigation to induce cell death; (2) increase stress to induce cellular catastrophe; and (3) exploit emergent vulnerabilities in cancer cells and cells of the tumour microenvironment. We review challenges associated with tumour heterogeneity, prioritizing actionable adaptive responses for optimal therapeutic outcomes, and development of an integrative framework to identify and target vulnerabilities that arise from adaptive responses and engagement of stress mitigation pathways. Finally, we discuss the need to monitor adaptive responses across multiple scales and translation of combination therapies designed to take advantage of adaptive responses and stress mitigation pathways to the clinic.

Tumor immune-gene expression profiles and peripheral immune phenotypes associated with clinical outcomes of locally advanced pancreatic cancer following FOLFIRINOX

Background

A comprehensive analysis of peripheral immune cell phenotypes and tumor immune-gene expression profiles in locally advanced pancreatic cancer patients treated with neoadjuvant chemotherapy in a phase II clinical trial was carried out.

Methods

Patients were treated with neoadjuvant modified folinic acid, fluorouracil, irinotecan hydrochloride, oxaliplatin (mFOLFIRINOX) followed by surgery and adjuvant gemcitabine at the Asan Medical Center. Correlations between survival outcomes and baseline peripheral immune cells and their changes during preoperative chemotherapy were analyzed. Patients who had surgery were divided into two groups according to achievement of disease-free survival >10 months (achieved versus failed). Differential expression and pathway analysis of immune-related genes were carried out using the Nanostring platform, and immune cells within the tumor microenvironment were compared by immunohistochemistry.

Results

Forty-four patients were treated in the phase II clinical trial. Higher baseline CD14+CD11c+HLA-DR+ monocytes (P = 0.044) and lower Foxp3+CD4+ T cells (P = 0.02) were associated with poor progression-free survival of neoadjuvant mFOLFIRINOX. During the preoperative chemotherapy, PD-1 T cells significantly decreased (P = 0.0110). Differential expression and pathway analysis of immune-genes from the resected tumor after neoadjuvant treatment revealed transforming growth factor-β pathway enrichment and higher expression of MARCO (adjusted P < 0.05) associated with early recurrence. Enrichment of the Th1 pathway and higher peritumoral CD8+ T cells (P = 0.0103) were associated with durable disease-free survival from surgery (>10 months) following neoadjuvant mFOLFIRINOX.

Conclusions

Our results identify potential immune biomarkers for locally advanced pancreatic cancer and provide insights into pancreatic cancer immunity.

•

We performed immune profiling of locally advanced pancreatic cancer treated with neoadjuvant therapy in a phase II trial.

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Proportion of programmed cell death protein 1-expressing peripheral CD8+ cells decreased after neoadjuvant chemotherapy.

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Lower peripheral monocytes and higher regulatory T cells were associated with better progression-free survival.

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Th1 pathway and higher peritumoral CD8+ T cells were associated with longer disease-free survival from surgery.

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Transforming growth factor-β pathway and higher MARCO expression were associated with early recurrence after surgery.

Mutually Exclusive Expression of COL11A1 by CAFs and Tumour Cells in a Large panCancer and a Salivary Gland Carcinoma Cohort

Procollagen 11A1 (COL11A1) is a central component of the extracellular matrix in many carcinomas, which is considered to be mainly produced by cancer associated fibroblasts (CAFs). As COL11A1 expression correlates with adverse prognosis and is implicated in chemoresistance, it is a promising putative target. For the first time, we used RNA in-situ hybridization to systematically identify the cells that produce COL11A1 in the ten most prevalent carcinoma types, lymphomas (n = 275) and corresponding normal tissue (n = 55; panCancer cohort). Moreover, as most salivary gland carcinomas (SGC) display distinct stromal architectures, we also analysed 110 SGC. The corresponding protein formation of COL11A1 was determined by MALDI-TOF-MS-Imaging. We report that colon, breast and salivary duct carcinomas are highly infiltrated by COL11A1 positive CAFs (CAFs_COL11A1) and might thus be promising candidates for antidesmoplastic or COL11A1-targeted therapies. The amount of CAFs_COL11A1 correlated significantly with tumour grade, tumour stage and nodal spread in the panCancer cohort. Significant associations between CAFs_COL11A1 and vascular invasion, perineural spread and nodal spread were observed in the SGC cohort. Also, we discovered that tumour cells of intercalated duct derived SGC and CAFs produce COL11A1 in a mutually exclusive manner. Our findings represent a novel mode of extracellular matrix production in carcinomas and could be highly relevant in the future. Our findings elucidate the mode of COL11A1 expression in very different carcinoma types and may aid to categorise tumours in the setting of possible future COL11A1-related therapies.