SMAD4 loss is associated with response to neoadjuvant chemotherapy plus hydroxychloroquine in patients with pancreatic adenocarcinoma

Hydroxychloroquine in combination with platinum doublet chemotherapy as first-line treatment for extensive-stage small cell lung cancer (Study 15): A randomised phase II multicentre trial

BACKGROUND

Most patients with small-cell lung cancer (SCLC) present with extensive-stage (ES) disease and have a poor prognosis despite achieving high initial response rates to platinum-based doublet chemotherapy. This study evaluated whether adding hydroxychloroquine (HCQ) to chemotherapy could improve outcomes.

METHODS

This was a randomised multicentre phase II trial. Eligible patients had untreated ES-SCLC, a performance status 0-2 and measurable disease. Patients were randomly assigned (1:1 ratio) to HCQ (400 mg orally twice daily) plus carboplatin-gemcitabine or carboplatin-etoposide alone. Chemotherapy was administered for up to six cycles, with HCQ given concurrently and then as single agent for up to 30 months. Primary endpoint was PFS, aiming for a hazard ratio (HR) of 0.70.

RESULTS

72 patients were randomised (36 HCQ+chemotherapy and 36 chemotherapy alone). Median HCQ treatment duration was 4.4 months. HCQ did not improve PFS (HR 1·12 95 %CI 0·69-1.84; p = 0·64), with a median of 5.7 months (HCQ+chemotherapy) versus 6.2 months (chemotherapy). The corresponding median OS were 8.9 and 10.2 months (HR 0.83, 95 %CI 0.48-1.45, p = 0.52). Fewer patients in the HCQ arm completed four cycles of chemotherapy due to adverse events (64 % vs. 81 %). Grade ≥ 3 adverse events were higher in the HCQ+chemotherapy arm (83.3 % vs. 27.8 %), primarily anaemia, neutropenia, and thrombocytopenia, partly due to the initially higher gemcitabine dose used CONCLUSIONS: Combining HCQ with platinum doublet chemotherapy did not improve PFS or OS outcomes for ES-SCLC, resulting in more patients stopping chemotherapy due to increased adverse events. When considered alongside other randomised studies of HCQ in cancer, the evidence collectively indicates a limited role for HCQ as a therapeutic option.

Mechanism of enhancing chemotherapy efficacy in pancreatic ductal adenocarcinoma with paricalcitol and hydroxychloroquine

Pancreatic ductal adenocarcinoma (PDAC) has a minimal (<15%) 5-year existence, in part due to resistance to chemoradiotherapy. Previous research reveals the impact of paricalcitol (P) and hydroxychloroquine (H) on altering the lysosomal fusion, decreasing stromal burden, and triggering PDAC to chemotherapies. This investigation aims to elucidate the molecular properties of the H and P combination and their potential in sensitizing PDAC to gemcitabine (G). PH potentiates the effects of G in in vitro, orthotopic mouse models, and a patient-derived xenograft model of PDAC. Proteomic and single-cell RNA sequencing (RNA-seq) analyses reveal that GPH treatment upregulates autophagy and endoplasmic reticulum (ER) stress-related transcripts. GPH treatment decreases the number of Ki67, fibroblast-associated protein (FAP), and alpha-smooth muscle actin (SMA)-expressing fibroblasts with a decrease in autophagy-related transcripts. The GPH treatment increases M1 polarization and CD4+ and CD8+ T cells and reduces CD4+ and CD8+ regulatory T cells (Tregs). These effects of GPH were confirmed in paired biopsies obtained from patients treated in a clinical trial (NCT04524702).

Emerging horizons on molecular and circulating biomarkers in pancreatic adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is the most aggressive and invasive type of pancreatic cancer and is expected to soon become the second leading cause of cancer-associated death. The high mortality rate is due to the clinical features that allow asymptomatic progression to advanced stages, a period when current therapeutic treatments have limited efficacy. To address these challenges, researchers are focused on identifying new molecular and circulating markers for early PDAC detection and precision medicine. In this mini-review, we report the most well-known and recently identified molecular and circulating biomarkers. This study aimed to emphasize the need for continued innovative research to develop diagnostic algorithms and therapies to improve the management of patients with PDAC.

SBRT for Pancreatic Cancer: A Radiosurgery Society Case-Based Practical Guidelines to Challenging Cases

The use of radiation therapy (RT) for pancreatic cancer continues to be controversial, despite recent technical advances. Improvements in systemic control have created an evolving role for RT and the need for improved local tumor control, but currently, no standardized approach exists. Advances in stereotactic body RT, motion management, real-time image guidance, and adaptive therapy have renewed hopes of improved outcomes in this devastating disease with one of the lowest survival rates. This case-based guide provides a practical framework for delivering stereotactic body RT for locally advanced pancreatic cancer. In conjunction with multidisciplinary care, an intradisciplinary approach should guide treatment of the high-risk cases outlined within these guidelines for prospective peer review and treatment safety discussions.

New insight into the role of SMAD4 mutation/deficiency in the prognosis and therapeutic resistance of pancreatic ductal adenocarcinomas

Pancreatic ductal adenocarcinoma (PDAC) patients have an unfavorable prognosis and disappointing treatment outcomes because of late diagnosis, high chemotherapy resistance, ineffective adjuvant chemotherapy, unavailable molecular targeted therapy, and profound immunosuppressive effects in the tumor microenvironment (TME). There are a variety of critical driver proteins, such as KRAS, TP53, PTEN and SMAD4, putatively involved in PDAC etiology. Current knowledge of their molecular mechanisms is still limited. SMAD4 gene alterations in ∼55 % of patients emphasize its key role in PDAC progression, metastasis, resistance and immunity. Despite extensive studies on the TGF-β/SMAD pathway, the impact of SMAD4 mutation/deficiency on PDAC prognosis and treatment, especially its mechanism in drug resistance, has not yet been elucidated. This review summarizes the latest advances in the effect of SMAD4 deficiency on the prognosis and therapeutic resistance of PDAC patients. It might be a predictive and prognostic biomarker or therapeutic target to achieve the desired clinical benefits. Moreover, we discuss potential strategies to implement targeted therapies in terms of SMAD4 genetic status.

Unveiling the Promise: Navigating Clinical Trials 1978-2024 for PDAC

Despite many decades of research, pancreatic ductal adenocarcinoma (PDAC) remains one of the most difficult cancers to diagnose and treat effectively. Although there have been improvements in the 5-year overall survival rate, it is still very low at 12.5%. The limited efficacy of current therapies, even when PDAC is detected early, underscores the aggressive nature of the disease and the urgent need for more effective treatments. Clinical management of PDAC still relies heavily on a limited repertoire of therapeutic interventions, highlighting a significant gap between research efforts and available treatments. Over 4300 clinical trials have been or are currently investigating different treatment modalities and diagnostic strategies for PDAC, including targeted therapies, immunotherapies, and precision medicine approaches. These trials aim to develop more effective treatments and improve early detection methods through advanced imaging techniques and blood-based biomarkers. This review seeks to categorize and analyze PDAC-related clinical trials across various dimensions to understand why so few chemotherapeutic options are available to patients despite the numerous trials being conducted. This review aims to provide a comprehensive and nuanced understanding of the landscape of PDAC-related clinical trials, with the overarching goal of identifying opportunities to accelerate progress in drug development and improve patient outcomes in the fight against this devastating disease.

Echinacoside ameliorates hepatic fibrosis and tumor invasion in rats with thioacetamide-induced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) affects approximately 800,000 individuals globally each year. Despite advancements in HCC treatments, there is still a pressing need to identify new drugs that can combat resistance. One potential option is echinacoside, a natural caffeic acid glycoside with antioxidant, anti-inflammatory, antidepressant, and antidiabetic properties. Therefore, we aimed to investigate the ability of echinacoside to exhibit antitumor activity against HCC in rats through ameliorating hepatic fibrosis and tumor invasion. Rats were given thioacetamide to induce HCC, and some were given 30 mg/kg of echinacoside twice a week for 16 weeks. The liver impairment was assessed by measuring serum α-fetoprotein (AFP) and examining liver sections stained with Masson trichrome or anti-transforming growth factor (TGF)-β1 antibodies. The hepatic expression of mRNA and protein levels of TGF-β1, β-catenin, SMAD4, matrix metalloproteinase-9 (MMP9), phosphoinositide 3-kinases (PI3K), mammalian target of rapamycin (mTOR), connective tissue growth factor 2 (CCN2), E-Cadherin, platelets derived growth factor (PDGF)-B and fascin were also analyzed. Echinacoside improved the survival rate of rats by decreasing serum AFP and the number of hepatic nodules. Examination of micro-images indicated that echinacoside can reduce fibrosis. It also significantly decreased the expression of TGF-β1, β-catenin, SMAD4, MMP9, PI3K, mTOR, CCN2, PDGF-B, and fascin while enhancing the expression of E-Cadherin. In conclusion, echinacoside exhibits a protective effect against HCC by increasing survival rates and decreasing tumor growth. It also acts as an inhibitor of the hepatic tissue fibrosis pathway by reducing the expression of TGF-β1, β-catenin, SMAD4, PI3K, CCN2, PDGF-B and mTOR. Additionally, it prevents tumor invasion by suppressing MMP9 and fascin, and increasing the expression of E-Cadherin.

Pharmacology Progresses and Applications of Chloroquine in Cancer Therapy

Chloroquine is a common antimalarial drug and is listed in the World Health Organization Standard List of Essential Medicines because of its safety, low cost and ease of use. Besides its antimalarial property, chloroquine also was used in anti-inflammatory and antivirus, especially in antitumor therapy. A mount of data showed that chloroquine mainly relied on autophagy inhibition to exert its antitumor effects. However, recently, more and more researches have revealed that chloroquine acts through other mechanisms that are autophagy-independent. Nevertheless, the current reviews lacked a comprehensive summary of the antitumor mechanism and combined pharmacotherapy of chloroquine. So here we focused on the antitumor properties of chloroquine, summarized the pharmacological mechanisms of antitumor progression of chloroquine dependent or independent of autophagy inhibition. Moreover, we also discussed the side effects and possible application developments of chloroquine. This review provided a more systematic and cutting-edge knowledge involved in the anti-tumor mechanisms and combined pharmacotherapy of chloroquine in hope of carrying out more in-depth exploration of chloroquine and obtaining more clinical applications.

Differential Sensitivity to Ionizing Radiation in Gemcitabine-Resistant and Paclitaxel-Resistant Pancreatic Cancer Cells

PURPOSE

Chemoresistance remains a major challenge in treating pancreatic ductal adenocarcinoma (PDAC). Although chemoradiation has proven effective in other tumor types, such as head and neck squamous cell carcinoma, its role in PDAC and effect on acquired chemoresistance have yet to be fully explored. In this study, we investigated the sensitivity of gemcitabine-resistant (GR) and paclitaxel-resistant (PR) PDAC cells to ionizing radiation (IR) and their underlying mechanisms.

METHODS AND MATERIALS

GR and PR clones were generated from PANC-1, PATU-T, and SUIT2-007 pancreatic cancer cell lines. Cell survival after radiation was assessed using clonogenic assay, sulforhodamine B assay, apoptosis, and spheroid growth by bioluminescence. Radiation-induced DNA damage was assessed using Western blot, extra-long polymerase chain reaction, reactive oxygen species production, and immunofluorescence. Autophagy and modulation of the Hippo signaling pathway were investigated using proteomics, Western blot, immunofluorescence, and reverse-transcription quantitative polymerase chain reaction.

RESULTS

In both 2- and 3-dimensional settings, PR cells were more sensitive to IR and showed decreased β-globin amplification, indicating more DNA damage accumulation compared with GR or wild-type cells after 24 hours. Proteomic analysis of PR PATU-T cells revealed that the protein MST4, a kinase involved in autophagy and the Hippo signaling pathway, was highly downregulated. A differential association was found between autophagy and radiation treatment depending on the cell model. Interestingly, increased yes-associated protein nuclear localization and downstream Hippo signaling pathway target gene expression were observed in response to IR.

CONCLUSIONS

This was the first study investigating the potential of IR in targeting PDAC cells with acquired chemoresistance. Our results demonstrate that PR cells exhibit enhanced sensitivity to IR due to greater accumulation of DNA damage. Additionally, depending on the specific cellular context, radiation-induced modulation of autophagy and the Hippo signaling pathway emerged as potential underlying mechanisms, findings with potential to inform personalized treatment strategies for patients with acquired chemoresistance.

Significance of TP53, CDKN2A, SMAD4 and KRAS in Pancreatic Cancer

The present review demonstrates the major tumor suppressor genes, including TP53, CDKN2A and SMAD4, associated with pancreatic cancer. Each gene's role, prevalence and impact on tumor development and progression are analyzed, focusing on the intricate molecular landscape of pancreatic cancer. In addition, this review underscores the prognostic significance of specific mutations, such as loss of TP53, and explores some potential targeted therapies tailored to these molecular signatures. The findings highlight the importance of genomic analyses for risk assessment, early detection and the design of personalized treatment approaches in pancreatic cancer. Overall, this review provides a comprehensive analysis of the molecular intricacies of pancreatic tumors, paving the way for more effective and tailored therapeutic interventions.

An NFATc1/SMAD3/cJUN Complex Restricted to SMAD4-Deficient Pancreatic Cancer Guides Rational Therapies

BACKGROUND & AIMS

The highly heterogeneous cellular and molecular makeup of pancreatic ductal adenocarcinoma (PDAC) not only fosters exceptionally aggressive tumor biology, but contradicts the current concept of one-size-fits-all therapeutic strategies to combat PDAC. Therefore, we aimed to exploit the tumor biological implication and therapeutic vulnerabilities of a clinically relevant molecular PDAC subgroup characterized by SMAD4 deficiency and high expression of the nuclear factor of activated T cells (SMAD4-/-/NFATc1High).

METHODS

Transcriptomic and clinical data were analyzed to determine the prognostic relevance of SMAD4-/-/NFATc1High cancers. In vitro and in vivo oncogenic transcription factor complex formation was studied by immunoprecipitation, proximity ligation assays, and validated cross model and species. The impact of SMAD4 status on therapeutically targeting canonical KRAS signaling was mechanistically deciphered and corroborated by genome-wide gene expression analysis and genetic perturbation experiments, respectively. Validation of a novel tailored therapeutic option was conducted in patient-derived organoids and cells and transgenic as well as orthotopic PDAC models.

RESULTS

Our findings determined the tumor biology of an aggressive and chemotherapy-resistant SMAD4-/-/NFATc1High subgroup. Mechanistically, we identify SMAD4 deficiency as a molecular prerequisite for the formation of an oncogenic NFATc1/SMAD3/cJUN transcription factor complex, which drives the expression of RRM1/2. RRM1/2 replenishes nucleoside pools that directly compete with metabolized gemcitabine for DNA strand incorporation. Disassembly of the NFATc1/SMAD3/cJUN complex by mitogen-activated protein kinase signaling inhibition normalizes RRM1/2 expression and synergizes with gemcitabine treatment in vivo to reduce the proliferative index.

CONCLUSIONS

Our results suggest that PDAC characterized by SMAD4 deficiency and oncogenic NFATc1/SMAD3/cJUN complex formation exposes sensitivity to a mitogen-activated protein kinase signaling inhibition and gemcitabine combination therapy.

Chloroquine and Chemotherapeutic Compounds in Experimental Cancer Treatment

Chloroquine (CQ) and its derivate hydroxychloroquine (HCQ), the compounds with recognized ability to suppress autophagy, have been tested in experimental works and in clinical trials as adjuvant therapy for the treatment of tumors of different origin to increase the efficacy of cytotoxic agents. Such a strategy can be effective in overcoming the resistance of cancer cells to standard chemotherapy or anti-angiogenic therapy. This review presents the results of the combined application of CQ/HCQ with conventional chemotherapy drugs (doxorubicin, paclitaxel, platinum-based compounds, gemcitabine, tyrosine kinases and PI3K/Akt/mTOR inhibitors, and other agents) for the treatment of different malignancies obtained in experiments on cultured cancer cells, animal xenografts models, and in a few clinical trials. The effects of such an approach on the viability of cancer cells or tumor growth, as well as autophagy-dependent and -independent molecular mechanisms underlying cellular responses of cancer cells to CQ/HCQ, are summarized. Although the majority of experimental in vitro and in vivo studies have shown that CQ/HCQ can effectively sensitize cancer cells to cytotoxic agents and increase the potential of chemotherapy, the results of clinical trials are often inconsistent. Nevertheless, the pharmacological suppression of autophagy remains a promising tool for increasing the efficacy of standard chemotherapy, and the development of more specific inhibitors is required.

Emodin derivative E35 and its combination with autophagy inhibitor against acute myeloid leukemia cells in vitro and in vivo

Acute myeloid leukemia (AML) is an aggressive hematopoietic malignancy with poor prognosis and high recurrence rate. The discovery of more effective therapeutic strategies for AML plays a crucial role. The present work showed that E35, a novel derivative of emodin, significantly inhibited cell proliferation and induced autophagy and apoptosis in AML cells. Treatment with E35 markedly induced Beclin-1, LC3-II, cleaved Caspase-9 and PARP, and suppressed mitogen-activated protein kinase (MAPK) pathway. E35 exposure evoked autophagic activity prior to apoptosis induction, and autophagy inhibition by 3-methyladenine (3-MA) dramatically increased E35-induced apoptosis in both AML cell lines and patient-derived AML cells. Nevertheless, study on AML xenograft model showed that the combination E35 with 3-MA exhibited much more inhibitory effects on leukemia cell growth in vivo. No obvious adverse reactions occurred in the xenograft animals administered E35 alone or its cotreatment with 3-MA. These findings suggest that E35 could exert anti-leukemia effects, and that the combination of E35 and autophagy inhibitor might prove a more highly efficient strategy for AML treatment.

Targeting KRAS in Pancreatic Ductal Adenocarcinoma: The Long Road to Cure

Pancreatic ductal adenocarcinoma (PDAC) remains an important cause of cancer-related mortality, and it is expected to play an even bigger part in cancer burden in the years to come. Despite concerted efforts from scientists and physicians, patients have experienced little improvement in survival over the past decades, possibly because of the non-specific nature of the tested treatment modalities. Recently, the discovery of potentially targetable molecular alterations has paved the way for the personalized treatment of PDAC. Indeed, the central piece in the molecular framework of PDAC is starting to be unveiled. KRAS mutations are seen in 90% of PDACs, and multiple studies have demonstrated their pivotal role in pancreatic carcinogenesis. Recent investigations have shed light on the differences in prognosis as well as therapeutic implications of the different KRAS mutations and disentangled the relationship between KRAS and effectors of downstream and parallel signaling pathways. Additionally, the recognition of other mechanisms involving KRAS-mediated pathogenesis, such as KRAS dosing and allelic imbalance, has contributed to broadening the current knowledge regarding this molecular alteration. Finally, KRAS G12C inhibitors have been recently tested in patients with pancreatic cancer with relative success, and inhibitors of KRAS harboring other mutations are under clinical development. These drugs currently represent a true hope for a meaningful leap forward in this dreadful disease.

Post-operative mortality and recurrence patterns in pancreatic cancer according to KRAS mutation and CDKN2A, p53, and SMAD4 expression

Alterations in KRAS, CDKN2A (p16), TP53, and SMAD4 genes have been major drivers of pancreatic carcinogenesis. The clinical course of patients with pancreatic cancer in relation to these driver alterations has not been fully characterised in large populations. We hypothesised that pancreatic carcinomas with different combinations of KRAS mutation and aberrant expression of CDKN2A, p53, and SMAD4 might show distinctive recurrence patterns and post-operative survival outcomes. To test this hypothesis, we utilised a multi-institutional cohort of 1,146 resected pancreatic carcinomas and assessed KRAS mutations by droplet digital polymerase chain reaction and CDKN2A, p53, and SMAD4 expression by immunohistochemistry. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) for disease-free survival (DFS) and overall survival (OS) were computed according to each molecular alteration and the number of altered genes using the Cox regression models. Multivariable competing risks regression analyses were conducted to assess the associations of the number of altered genes with specific patterns of recurrence. Loss of SMAD4 expression was associated with short DFS (multivariable HR, 1.24; 95% CI, 1.09-1.43) and OS times (multivariable HR, 1.27; 95% CI, 1.10-1.46). Compared to cases with 0-2 altered genes, cases with three and four altered genes had multivariable HRs for OS of 1.28 (95% CI, 1.09-1.51) and 1.47 (95% CI, 1.22-1.78), respectively (ptrend  < 0.001). Patients with an increasing number of altered genes were more likely to have short DFS time (ptrend  = 0.003) and to develop liver metastasis (ptrend  = 0.006) rather than recurrence at local or other distant sites. In conclusion, loss of SMAD4 expression and an increasing number of altered genes were associated with unfavourable outcomes in pancreatic cancer patients. This study suggests that the accumulation of the four major driver alterations can confer a high metastatic potential to the liver, thereby impairing post-operative survival among patients with pancreatic cancer.

Recent advances in targeting autophagy in cancer

Autophagy is a cellular homeostasis mechanism that fuels the proliferation and survival of advanced cancers by degrading and recycling organelles and proteins. Preclinical studies have identified that within an established tumor, tumor cell autophagy and host cell autophagy conspire to support tumor growth. A growing body of evidence suggests that autophagy inhibition can augment the efficacy of chemotherapy, targeted therapy, or immunotherapy to enhance tumor shrinkage. First-generation autophagy inhibition trials in cancer using the lysosomal inhibitor hydroxychloroquine (HCQ) have produced mixed results but have guided the way for the development of more potent and specific autophagy inhibitors in clinical trials. In this review, we will discuss the role of autophagy in cancer, newly discovered molecular mechanisms of the autophagy pathway, the effects of autophagy modulation in cancer and host cells, and novel autophagy inhibitors that are entering clinical trials.

Autophagy in cancer resistance to paclitaxel: Development of combination strategies

Paclitaxel, a compound naturally occurring in yew, is a commonly used drug for the treatment of different types of cancer. Unfortunately, frequent cancer cell resistance significantly decreases its anticancer effectivity. The main reason for the resistance development is the paclitaxel-induced phenomenon of cytoprotective autophagy occurring by different mechanisms of action in dependence on a cell type and possibly even leading to metastases. Paclitaxel also induces autophagy in cancer stem cells, which greatly contributes to tumor resistance development. Paclitaxel anticancer effectivity can be predicted by the presence of several autophagy-related molecular markers, such as tumor necrosis factor superfamily member 13 in triple-negative breast cancer or cystine/glutamate transporter encoded by the SLC7A11 gene in ovarian cancer. Nevertheless, the undesired effects of paclitaxel-induced autophagy can be eliminated by paclitaxel co-administration with autophagy inhibitors, such as chloroquine. Interestingly, in certain cases, it is worthy of potentiating autophagy by paclitaxel combination with autophagy inducers, for instance, apatinib. A modern strategy in anticancer research is also to encapsulate chemotherapeutics into nanoparticle carriers or develop their novel derivatives with improved anticancer properties. Hence, in this review article, we summarize not only the current knowledge of paclitaxel-induced autophagy and its role in cancer resistance but mainly the possible drug combinations based on paclitaxel and their administration in nanoparticle-based formulations as well as paclitaxel analogs with autophagy-modulating properties.

Multiple roles of mothers against decapentaplegic homolog 4 in tumorigenesis, stem cells, drug resistance, and cancer therapy

The transforming growth factor (TGF)-β signaling pathway controls many cellular processes, including proliferation, differentiation, and apoptosis. Abnormalities in the TGF-β signaling pathway and its components are closely related to the occurrence of many human diseases, including cancer. Mothers against decapentaplegic homolog 4 (Smad4), also known as deleted in pancreatic cancer locus 4, is a typical tumor suppressor candidate gene locating at q21.1 of human chromosome 18 and the common mediator of the TGF-β/Smad and bone morphogenetic protein/Smad signaling pathways. It is believed that Smad4 inactivation correlates with the development of tumors and stem cell fate decisions. Smad4 also interacts with cytokines, miRNAs, and other signaling pathways, jointly regulating cell behavior. However, the regulatory function of Smad4 in tumorigenesis, stem cells, and drug resistance is currently controversial. In addition, Smad4 represents an attractive therapeutic target for cancer. Elucidating the specific role of Smad4 is important for understanding the mechanism of tumorigenesis and cancer treatment. Here, we review the identification and characterization of Smad4, the canonical TGF-β/Smad pathway, as well as the multiple roles of Smad4 in tumorigenesis, stem cells, and drug resistance. Furthermore, we provide novel insights into the prospects of Smad4-targeted cancer therapy and the challenges that it will face in the future.