Autophagy Inhibition in Pancreatic Adenocarcinoma

Niraparib perturbs autophagosome-lysosome fusion in pancreatic ductal adenocarcinoma and exhibits anticancer potential against gemcitabine-resistant PDAC

While poly (adenosine diphosphate-ribose) polymerase inhibitors (PARPi) have achieved specific clinical benefits in a subset of pancreatic ductal adenocarcinoma (PDAC) patients, the potential role of the PARPi niraparib in PDAC necessitates further exploration. In this study, we demonstrated that Niraparib exhibited a pronounced inhibitory effect on autophagy in PDAC both in vitro and in vivo. Mechanistically, this inhibition was primarily attributed to niraparib's ability to disrupt the fusion process between autophagosomes and lysosomes, while potentially exerting a relatively minor impact on the initial stage of autophagy. The blockade effect observed may be mediated via modulation of the ERK signaling pathway, and this effect can be mitigated by the application of an ERK inhibitor (FR180204). Notably, the combined treatment regimen of niraparib and gemcitabine failed to elicit the anticipated synergistic effects in wild-type PANC-1 cells, instead exhibiting pronounced antagonistic interactions. However, in gemcitabine-resistant PANC-1 cells, the combination of niraparib and gemcitabine exhibited modest additive effects. Furthermore, niraparib demonstrated a heightened cytotoxic potency against gemcitabine-resistant PANC-1 cells compared to wild-type PANC-1 cells, both in vitro and in vivo. Our research established that niraparib inhibits late-stage autophagy in PDAC, potentially representing a valuable salvage therapy for gemcitabine-resistant PDAC. Further clinical studies are justified.

The Application of Electromagnetic Fields in Cancer

The use of nonionizing electromagnetic fields (EMFs) has attracted interest in cancer research during the past few decades due to its noninvasive therapeutic successes in the treatment of cancer. Some epidemiological studies suggest that there may be a link between exposure to EMF and developing malignancies (such as leukemia and gliomas) or neurodegenerative diseases since EMF has a variety of biological effects such as altering reactive oxygen species (ROS)-regulated pathways. EMF exposure, however, has the potential to cause cancer cells to undergo a period of regulated cell death. Therefore, it is important to thoroughly investigate how EMF might influence cellular processes such as proliferation, differentiation, and apoptosis - processes that are targeted in cancer treatment. In this chapter, we give a thorough summary of the most recent studies on the potential use of various EMF applications with adjustable settings to treat different forms of cancer.

Blockade of DDR1/PYK2/ERK signaling suggesting SH2 superbinder as a novel autophagy inhibitor for pancreatic cancer

Pancreatic cancer is highly lethal, of which 90% is pancreatic ductal adenocarcinoma (PDAC), with a 5-year survival rate of less than 12%, lacking effective treatment options and late diagnosis. Furthermore, the tumors show an intense resistance to cytotoxic chemotherapies. As autophagy is elevated in PDAC, targeting the autophagic pathway is regarded as a promising strategy for cancer treatment. Immunofluorescence and transmission electron microscopy were utilized to assess the autophagic flux. Label-free quantitative phosphoproteomics was used to figure out critically altered tyrosine phosphorylation of the proteins. Tumor-bearing mice were used to validate that SH2 TrM-(Arg)9 restrained the growth of tumor cells. SH2 TrM-(Arg)9 inhibited collagen-induced autophagy via blocking the DDR1/PYK2/ERK signaling cascades. SH2 TrM-(Arg)9 improved the sensitivity of PANC-1/GEM cells to gemcitabine (GEM). Inhibition of autophagy by SH2 TrM-(Arg)9 may synergized with chemotherapy and robusted tumor suppression in pancreatic cancer xenografts. SH2 TrM-(Arg)9 could enter into PDAC cells and blockade autophagy through inhibiting DDR1/PYK2/ERK signaling and may be a new treatment strategy for targeted therapy of PDAC.

Recent advances in targeted therapy for pancreatic adenocarcinoma

Pancreatic adenocarcinoma (PDAC) is a fatal disease with a 5-year survival rate of 8% and a median survival of 6 mo. In PDAC, several mutations in the genes are involved, with Kirsten rat sarcoma oncogene (90%), cyclin-dependent kinase inhibitor 2A (90%), and tumor suppressor 53 (75%–90%) being the most common. Mothers against decapentaplegic homolog 4 represents 50%. In addition, the self-preserving cancer stem cells, dense tumor microenvironment (fibrous accounting for 90% of the tumor volume), and suppressive and relatively depleted immune niche of PDAC are also constitutive and relevant elements of PDAC. Molecular targeted therapy is widely utilized and effective in several solid tumors. In PDAC, targeted therapy has been extensively evaluated; however, survival improvement of this aggressive disease using a targeted strategy has been minimal. There is currently only one United States Food and Drug Administration-approved targeted therapy for PDAC – erlotinib, but the absolute benefit of erlotinib in combination with gemcitabine is also minimal (2 wk). In this review, we summarize current targeted therapies and clinical trials targeting dysregulated signaling pathways and components of the PDAC oncogenic process, analyze possible reasons for the lack of positive results in clinical trials, and suggest ways to improve them. We also discuss emerging trends in targeted therapies for PDAC: combining targeted inhibitors of multiple pathways. The PubMed database and National Center for Biotechnology Information clinical trial website (www.clinicaltrials.gov) were queried to identify completed and published (PubMed) and ongoing (clinicaltrials.gov) clinical trials (from 2003-2022) using the keywords pancreatic cancer and targeted therapy. The PubMed database was also queried to search for information about the pathogenesis and molecular pathways of pancreatic cancer using the keywords pancreatic cancer and molecular pathways.

Biologic Functions of Hydroxychloroquine in Disease: From COVID-19 to Cancer

Chloroquine (CQ) and Hydroxychloroquine (HCQ), initially utilized in the treatment of malaria, have now developed a long list of applications. Despite their clinical relevance, their mechanisms of action are not clearly defined. Major pathways by which these agents are proposed to function include alkalinization of lysosomes and endosomes, downregulation of C-X-C chemokine receptor type 4 (CXCR4) expression, high-mobility group box 1 protein (HMGB1) inhibition, alteration of intracellular calcium, and prevention of thrombus formation. However, there is conflicting data present in the literature. This is likely the result of the complex overlapping pathways between these mechanisms of action that have not previously been highlighted. In fact, prior research has focused on very specific portions of particular pathways without describing these in the context of the extensive CQ/HCQ literature. This review summarizes the detailed data regarding CQ/HCQ's mechanisms of action while also providing insight into the overarching themes. Furthermore, this review provides clinical context to the application of these diverse drugs including their role in malaria, autoimmune disorders, cardiovascular disease, thrombus formation, malignancies, and viral infections.

Four drug metabolism-related subgroups of pancreatic adenocarcinoma in prognosis, immune infiltration, and gene mutation

We aimed to screen the drug metabolism-related subgroups of pancreatic adenocarcinoma (PAAD) and to study the prognosis, clinical features, immune infiltration, and gene mutation differences of different subtypes in PAAD patients. All 181 cases of PAAD samples and clinical characteristics data were downloaded from The Cancer Genome Atlas (TCGA). After matching the drug metabolism-related genes downloaded from PMID 33202946 with the TCGA dataset, the drug metabolism-related genes were initially obtained. Besides, univariate Cox regression analysis was used to screen the drug metabolism genes related to the prognosis of PAAD. Moreover, the construction of the protein–protein interaction (PPI) network and gene ontology were performed. The four subgroups of PAAD obtained from unsupervised clustering analysis were systematically analyzed, including prognostic, GSVA, immune infiltration, and gene mutation analysis. A total of 83 drug metabolism genes related to the prognosis of PAAD were obtained and enriched in 16 pathways. The PPI network was composed of 248 relationship pairs. Four subgroups that can identify different subtypes of PPAD were obtained, and there were significant differences in survival and clinical characteristics, mutation types, and immune infiltration abundance between subgroups. A total of 17 different pathways among the four subgroups involved in cell cycle, response to stimulants such as drugs, and transmembrane transport. In this study, the four subgroups related to the drug metabolism of PAAD were comprehensively analyzed, and the important role of drug metabolism-related genes in the immune infiltration and prognosis of PAAD were emphasized.

Small Molecule MMRi62 Induces Ferroptosis and Inhibits Metastasis in Pancreatic Cancer via Degradation of Ferritin Heavy Chain and Mutant p53

High frequency of KRAS and TP53 mutations is a unique genetic feature of pancreatic ductal adenocarcinoma (PDAC). TP53 mutation not only renders PDAC resistance to chemotherapies but also drives PDAC invasiveness. Therapies targeting activating mutant KRAS are not available and the outcomes of current PDAC treatment are extremely poor. Here we report that MMRi62, initially identified as an MDM2-MDM4-targeting small molecule with p53-independent pro-apoptotic activity, shows anti-PDAC activity in vitro and in vivo. We show that MMRi62 inhibits proliferation, clonogenic and spheroid growth of PDAC cells by induction of cell death. MMRi62-induced cell death in PDAC is characteristic of ferroptosis which is associated with increased autophagy, increased reactive oxygen species and lysosomal degradation of NCOA4 and Ferritin Heavy Chain (FTH1). In addition to induced degradation of FTH1, MMRi62 also induces proteasomal degradation of mutant p53. Interestingly, MMRi62-induced ferroptosis occurs in PDAC cell lines harboring either KRAS and TP53 double mutations or single TP53 mutation. In orthotopic xenograft PDAC mouse models, MMRi62 was capable of inhibiting tumor growth in mice associated with downregulation of NCOA4 and mutant p53 in vivo. Strikingly, MMRi62 completely abrogated metastasis of orthotopic tumors to distant organs, which is consistent with MMRi62's ability to inhibit cell migration and invasion in vitro. These findings identified MMRi62 as a novel ferroptosis inducer capable of suppressing PDAC growth and overcoming metastasis.

Radiosensitizing Pancreatic Cancer via Effective Autophagy Inhibition

Despite aggressive treatments, pancreatic ductal adenocarcinoma (PDAC) remains an intractable disease, largely because it is refractory to therapeutic interventions. To overcome its nutrient-poor microenvironment, PDAC heavily relies on autophagy for metabolic needs to promote tumor growth and survival. Here, we explore autophagy inhibition as a method to enhance the effects of radiotherapy on PDAC tumors. Hydroxychloroquine is an autophagy inhibitor at the focus of many PDAC clinical trials, including in combination with radiotherapy. However, its acid-labile properties likely reduce its intratumoral efficacy. Here, we demonstrate that EAD1, a synthesized analogue of HCQ, is a more effective therapeutic for sensitizing PDAC tumors of various KRAS mutations to radiotherapy. Specifically, in vitro models show that EAD1 is an effective inhibitor of autophagic flux in PDAC cells, accompanied by a potent inhibition of proliferation. When combined with radiotherapy, EAD1 is consistently superior to HCQ not only as a single agent, but also in radiosensitizing PDAC cells, and perhaps most importantly, in decreasing the self-renewal capacity of PDAC cancer stem cells (PCSC). The more pronounced sensitizing effects of autophagy inhibitors on pancreatic stem over differentiated cells points to a new understanding that PCSCs may be more dependent on autophagy to counter the effects of radiation toxicity, a potential mechanism explaining the resistance of PCSCs to radiotherapy. Finally, in vivo subcutaneous tumor models demonstrate that combination of radiotherapy and EAD1 is the most successful at controlling tumor growth. The models also confirmed a similar toxicity profile between EAD1 and Hydroxychloroquine.

Sequestsome-1/p62-targeted small molecules for pancreatic cancer therapy

Pancreatic ductal adenocarcinoma (PDAC) is characterized by heightened autophagy and systemic immune dysfunction. Modest improvements in clinical outcomes have been demonstrated in completed clinical trials targeting autophagy with combination hydroxychloroquine (HCQ) and chemotherapy. Recent mechanistic insights into the role of autophagy-dependent immune evasion have prompted the need for more precise and druggable targets of autophagy inhibition. Sequestosome-1 (SQSTM-1) is a multidomain scaffold protein with well-established roles in autophagy, tumor necrosis factor alpha (TNFα)- and NF-κB-related signaling pathways. SQSTM1 overexpression is frequently observed in PDAC, correlating with clinical stage and outcome. Given the unique molecular structure of SQSTM-1 and its diverse activity, identifying means of limiting SQSTM-1-dependent autophagy to promote an effective immune response in PDAC could be a promising treatment strategy.

Chloroquine Potentiates the Anticancer Effect of Pterostilbene on Pancreatic Cancer by Inhibiting Autophagy and Downregulating the RAGE/STAT3 Pathway

The treatment of pancreatic ductal adenocarcinoma (PDAC) remains a huge challenge, because pro-survival signaling pathways—such as the receptor for advanced glycation end products (RAGE)/signal transducer and activator of transcription 3 (STAT3) pathway—are overexpressed in PDAC cells. Moreover, PDAC cells are highly resistant to chemotherapeutic agents because of autophagy induction. Therefore, autophagy and its modulated signaling pathways are attractive targets for developing novel therapeutic strategies for PDAC. Pterostilbene is a stilbenoid chemically related to resveratrol, and has potential for the treatment of cancers. Accordingly, we investigated whether the autophagy inhibitor chloroquine could potentiate the anticancer effect of pterostilbene in the PDAC cell lines MIA PaCa-2 and BxPC-3, as well as in an orthotopic animal model. The results indicated that pterostilbene combined with chloroquine significantly inhibited autophagy, decreased cell viability, and sensitized the cells to pterostilbene-induced apoptosis via downregulation of the RAGE/STAT3 and protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathways in PDAC cells. The results of the orthotopic animal model showed that pterostilbene combined with chloroquine significantly inhibited pancreatic cancer growth, delayed tumor quadrupling times, and inhibited autophagy and STAT3 in pancreatic tumors. In summary, the present study suggested the novel therapeutic strategy of pterostilbene combined with chloroquine against the growth of pancreatic ductal adenocarcinoma by inhibiting autophagy and downregulating the RAGE/STAT3 signaling pathways.

Encouraging long-term survival following autophagy inhibition using neoadjuvant hydroxychloroquine and gemcitabine for high-risk patients with resectable pancreatic carcinoma

INTRODUCTION

Preoperative autophagy inhibition with hydroxychloroquine (HCQ) in combination with gemcitabine in pancreatic adenocarcinoma (PDAC) has been shown to be safe and effective in inducing a serum biomarker response and increase resection rates in a previous phase I/II clinical trial. We aimed to analyze the long-term outcomes of preoperative HCQ with gemcitabine for this cohort.

METHODS

A review of patients enrolled between July 2010 and February 2013 in the completed phase I/II single arm (two doses of fixed-dose gemcitabine (1500 mg/m2 ) in combination with oral hydroxychloroquine administered for 31 consecutive days until the day of surgery for high-risk pancreatic cancer) was undertaken. Progression-free survival (PFS) and overall survival analysis (OS) using Kaplan-Meier estimates were performed.

RESULTS

Of 35 patients initially enrolled, 29 patients underwent surgical resection (median age at diagnosis: 62 years, 45% females). Median duration of follow-up was 7.5 years. There was a median 15% decrease in the serum CA19-9 levels following completion of neoadjuvant therapy and 83% of the cohort underwent a pancreaticoduodenectomy, 7 (24%) patients had a concomitant venous resection. On histopathology, 14 (48%) patients had at least a partial treatment response. The median PFS and OS were 11 months (95% Confidence interval [CI]: 7-28) and 31 months (95% CI: 13-47), respectively, while 9 (31%) patients survived beyond 5 years from diagnosis; a rate that compares very favorably with contemporaneous series.

CONCLUSION

Compared to historical data, neoadjuvant autophagy inhibition with HCQ plus gemcitabine is associated with encouraging long-term survival for patients with PDAC.

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

SMAD4, a tumor suppressor gene, is lost in up to 60%-90% of pancreatic adenocarcinomas (PDAs). Loss of SMAD4 allows tumor progression by upregulating autophagy, a cell survival mechanism that counteracts apoptosis and allows intracellular recycling of macromolecules. Hydroxychloroquine (HCQ) is an autophagy inhibitor. We studied whether HCQ treatment in SMAD4 deficient PDA may prevent therapeutic resistance induced by autophagy upregulation. We retrospectively analyzed the SMAD4 status of patients with PDA enrolled in two prospective clinical trials evaluating pre-operative HCQ. The first dose escalation trial demonstrated the safety of preoperative gemcitabine with HCQ (NCT01128296). More recently, a randomized trial of gemcitabine/nab-paclitaxel +/- HCQ evaluated Evans Grade histopathologic response (NCT01978184). The effect of SMAD4 loss on response to HCQ and chemotherapy was studied for association with clinical outcome. Fisher's exact test and log-rank test were used to assess response and survival. Fifty-two patients receiving HCQ with neoadjuvant chemotherapy were studied. Twenty-five patients had SMAD4 loss (48%). 76% of HCQ-treated patients with SMAD4 loss obtained a histopathologic response greater than or equal to 2A, compared with only 37% with SMAD4 intact (p = 0.006). Although loss of SMAD4 has been associated with worse outcomes, in the current study, loss of SMAD4 was not associated with a detriment in median overall survival in HCQ-treated patients (34.43 months in SMAD4 loss vs. 27.27 months in SMAD4 intact, p = 0.18). The addition of HCQ to neoadjuvant chemotherapy in patients with PDA may improve treatment response in those with SMAD4 loss. Further study of the relationship among SMAD4, autophagy, and treatment outcomes in PDA is warranted.

Progressive Study on the Non-thermal Effects of Magnetic Field Therapy in Oncology

Cancer is one of the most common causes of death worldwide. Although the existing therapies have made great progress and significantly improved the prognosis of patients, it is undeniable that these treatment measures still cause some serious side effects. In this context, a new treatment method is needed to address these shortcomings. In recent years, the magnetic fields have been proposed as a novel treatment method with the advantages of less side effects, high efficiency, wide applications, and low costs without forming scars. Previous studies reported that static magnetic fields (SMFs) and low-frequency magnetic fields (LF-MFs, frequency below 300 Hz) exert anti-tumor function, independent of thermal effects. Magnetic fields (MFs) could inhibit cell growth and proliferation; induce cell cycle arrest, apoptosis, autophagy, and differentiation; regulate the immune system; and suppress angiogenesis and metastasis via various signaling pathways. In addition, they are effective in combination therapies: MFs not only promote the absorption of chemotherapy drugs by producing small holes on the surface of cell membrane but also enhance the inhibitory effects by regulating apoptosis and cell cycle related proteins. At present, MFs can be used as drug delivery systems to target magnetic nanoparticles (MNPs) to tumors. This review aims to summarize and analyze the current knowledge of the pre-clinical studies of anti-tumor effects and their underlying mechanisms and discuss the prospects of the application of MF therapy in cancer prevention and treatment.

Actively Targeted Nanodelivery of Echinomycin Induces Autophagy-Mediated Death in Chemoresistant Pancreatic Cancer In Vivo

Pancreatic cancer remains a recalcitrant neoplasm associated with chemoresistance and high fatality. Because it is frequently resistant to apoptosis, exploiting autophagic cell death could offer a new treatment approach. We repurpose echinomycin, an antibiotic encapsulated within a syndecan-1 actively targeted nanoparticle, for treatment of pancreatic cancer. Tumor-specific uptake, biodistribution, efficacy of nanodelivered echinomycin, and mechanism of cell death were assessed in aggressive, metastatic models of pancreatic cancer. In these autophagic-dependent pancreatic cancer models, echinomycin treatment resulted in autophagic cell death noted by high levels of LC3 among other autophagy markers, but without hallmarks of apoptosis, e.g., caspase activation and chromatin fragmentation, or necrosis, e.g., plasma membrane degradation and chromatin condensation/degrading. In vivo, biodistribution of syndecan-1-targeted nanoparticles indicated preferential S2VP10 or S2CP9 tumor uptake compared to the liver and kidney (S2VP10 p = 0.0016, p = 0.00004 and S2CP9 p = 0.0009, p = 0.0001). Actively targeted nanodelivered echinomycin resulted in significant survival increases compared to Gemzar (S2VP10 p = 0.0003, S2CP9 p = 0.0017) or echinomycin only (S2VP10 p = 0.0096, S2CP9 p = 0.0073). We demonstrate that actively targeted nanodelivery of echinomycin results in autophagic cell death in pancreatic and potentially other high-autophagy, apoptosis-resistant tumors. Collectively, these findings support syndecan-1-targeted delivery of echinomycin and dysregulation of autophagy to induce cell death in pancreatic cancer.

A randomised phase II trial of hydroxychloroquine and imatinib versus imatinib alone for patients with chronic myeloid leukaemia in major cytogenetic response with residual disease

In chronic-phase chronic myeloid leukaemia (CP-CML), residual BCR-ABL1+ leukaemia stem cells are responsible for disease persistence despite TKI. Based on in vitro data, CHOICES (CHlorOquine and Imatinib Combination to Eliminate Stem cells) was an international, randomised phase II trial designed to study the safety and efficacy of imatinib (IM) and hydroxychloroquine (HCQ) compared with IM alone in CP-CML patients in major cytogenetic remission with residual disease detectable by qPCR. Sixty-two patients were randomly assigned to either arm. Treatment 'successes' was the primary end point, defined as ≥0.5 log reduction in 12-month qPCR level from trial entry. Selected secondary study end points were 24-month treatment 'successes', molecular response and progression at 12 and 24 months, comparison of IM levels, and achievement of blood HCQ levels >2000 ng/ml. At 12 months, there was no difference in 'success' rate (p = 0.58); MMR was achieved in 80% (IM) vs 92% (IM/HCQ) (p = 0.21). At 24 months, the 'success' rate was 20.8% higher with IM/HCQ (p = 0.059). No patients progressed. Seventeen serious adverse events, including four serious adverse reactions, were reported; diarrhoea occurred more frequently with combination. IM/HCQ is tolerable in CP-CML, with modest improvement in qPCR levels at 12 and 24 months, suggesting autophagy inhibition maybe of clinical value in CP-CML.

A Randomized Phase II Preoperative Study of Autophagy Inhibition with High-Dose Hydroxychloroquine and Gemcitabine/Nab-Paclitaxel in Pancreatic Cancer Patients

PURPOSE

We hypothesized that autophagy inhibition would increase response to chemotherapy in the preoperative setting for patients with pancreatic adenocarcinoma. We performed a randomized controlled trial to assess the autophagy inhibitor hydroxychloroquine in combination with gemcitabine and nab-paclitaxel.

PATIENTS AND METHODS

Participants with potentially resectable tumors were randomized to two cycles of nab-paclitaxel and gemcitabine (PG) alone or with hydroxychloroquine (PGH), followed by resection. The primary endpoint was histopathologic response in the resected specimen. Secondary clinical endpoints included serum CA 19-9 biomarker response and margin negative R0 resection. Exploratory endpoints included markers of autophagy, immune infiltrate, and serum cytokines.

RESULTS

Thirty-four patients in the PGH arm and 30 in the PG arm were evaluable for the primary endpoint. The PGH arm demonstrated statistically improved Evans grade histopathologic responses (P = 0.00016), compared with control. In patients with elevated CA 19-9, a return to normal was associated with improved overall and recurrence-free survival (P < 0.0001). There were no differences in serious adverse events between arms and chemotherapy dose number was equivalent. The PGH arm had greater evidence of autophagy inhibition in their resected specimens (increased SQSTM1, P = 0.027, as well as increased immune cell tumor infiltration, P = 0.033). Overall survival (P = 0.59) and relapse-free survival (P = 0.55) did not differ between the two arms.

CONCLUSIONS

The addition of hydroxychloroquine to preoperative gemcitabine and nab-paclitaxel chemotherapy in patients with resectable pancreatic adenocarcinoma resulted in greater pathologic tumor response, improved serum biomarker response, and evidence of autophagy inhibition and immune activity.

Synergistic cytotoxicity and co-autophagy inhibition in pancreatic tumor cells and cancer-associated fibroblasts by dual functional peptide-modified liposomes

Pancreatic ductal adenocarcinoma (PDA) is a highly fatal disease with 5-year survival of ∼8.5%. Nanoplatforms such as nab-paclitaxel and nanoliposomal irinotecan demonstrate superiority and utility in treating different progressions of PDA by prolonging the median overall survival by only a few months. Due to the dense surrounding stroma and the high autophagy in pancreatic cancer, integrin ɑ_vβ₃ targeting, acid environmental sensitive, TR peptide-modified liposomal platforms loaded with combined autophagy inhibiting hydroxychloroquine (HCQ), and cytotoxic paclitaxel (PTX) were designed (TR-PTX/HCQ-Lip) to accomplish the aim of synergistically killing tumor cells while inhibiting stroma fibrosis. The results showed that TR peptide-modified liposomes (TR-Lip) have superior targeting and penetrating effects both in vitro and in vivo. TR-PTX/HCQ-Lip efficiently inhibited autophagy in pancreatic cells and surrounding cancer-associated fibroblasts. The synergistic anti-fibrosis roles were also confirmed both in vitro and in vivo, all of which contributes to the enhanced curative effects of TR-PTX/HCQ-Lip in both heterogenetic and orthotopic pancreatic cancer models. STATEMENT OF SIGNIFICANCE: Autophagy plays a significant role in pancreatic ductal adenocarcinoma, especially in activating cancer associated fibroblasts which is also related to collagen generation that promotes the formation of dense stroma, which hinder the cytotoxic drugs to target and kill cancer cells. In this study, we designed integrin ɑvβ3 targeting, acid environmental sensitive liposomal platforms to co-loaded paclitaxel and the autophagy inhibitor hydroxychloroquine. The results showed that the muti-functional liposomes can target to the pancreatic tumor and efficiently kill tumor cells and inhibit stroma fibrosis, thus improve the therapeutic effect in orthotopic pancreatic cancer models.

Molecular targets of β-elemene, a herbal extract used in traditional Chinese medicine, and its potential role in cancer therapy: A review

β-Elemene is a sesquiterpene compound extracted from the herb Curcuma Rhizoma and is used in traditional Chinese medicine (TCM) to treat several types of cancer, with no reported severe adverse effects. Recent studies, using in vitro and in vivo studies combined with molecular methods, have shown that β-elemene can inhibit cell proliferation, arrest the cell cycle, and induce cell apoptosis. Recent studies have identified the molecular targets of β-elemene that may have a role in cancer therapy. This review aims to discuss the anticancer potential of β-elemene through its actions on several molecular targets including kinase enzymes, transcription factors, growth factors and their receptors, and proteins. β-Elemene also regulates the expression of several key molecules that are involved in tumor angiogenesis and metastasis including vascular endothelial growth factor (VEGF), matrix metalloproteinases (MMPs), E-cadherin, N-cadherin, and vimentin. Also, β-elemene has been shown to have regulatory effects on the immune response and increases the sensitivity of cancer cells to chemoradiotherapy and has shown effects on multidrug resistance (MDR) in malignancy. Recent studies have shown that β-elemene can induce autophagy, which prevents cancer cells from undergoing apoptosis. Therefore, the molecular mechanisms for the treatment effects on cancer of the herbal extract, β-elemene, which has been used for centuries in traditional Chinese medicine, are now being studied and identified.

Combination Therapy of Chloroquine and C₂-Ceramide Enhances Cytotoxicity in Lung Cancer H460 and H1299 Cells

Non-small cell lung cancer (NSCLC) is a type of malignant cancer, and 85% of metastatic NSCLC patients have a poor prognosis. C₂-ceramide induces G2/M phase arrest and cytotoxicity in NSCLC cells. In this study, the autophagy-inducing effect of C₂-ceramide was demonstrated, and cotreatment with the autophagy inhibitor chloroquine (CQ) was investigated in NSCLC H460 and H1299 cells. The results suggested that C₂-ceramide exhibited dose-dependent anticancer effects in H460 and H1299 cells and autophagy induction. Zebrafish-based acridine orange staining confirmed the combined effects in vivo. Importantly, the combination of a sublethal dose of C₂-ceramide and CQ resulted in additive cytotoxicity and autophagy in both cell lines. Alterations of related signaling factors, including Src and SIRT1 inhibition and activation of the autophagic regulators LAMP2 and LC3-I/II, contributed to the autophagy-dependent apoptosis. We found that C₂-ceramide continuously initiated autophagy; however, CQ inhibited autophagosome maturation and degradation during autophagy progression. Accumulated and non-degraded autophagosomes increased NSCLC cell stress, eventually leading to cell death. This study sheds light on improvements to NSCLC chemotherapy to reduce the chemotherapy dose and NSCLC patient burden.

The progression of HMGB1-induced autophagy in cancer biology

Autophagy is an important process of cellular degradation and has been proven to contribute to tumorigenesis. High-mobility group box 1 (HMGB1) is an abundant nonhistone protein that has been widely reported to play a central role in the induction of autophagy. In nucleus, HMGB1 upregulates the expression of HSP27 to induce autophagy. In cytoplasm, the Beclin-1/PI3K-III complex can be activated by HMGB1 to promote autophagy. Extracellular HMGB1 binds to the receptor for advanced glycation end products to induce autophagy. Recent studies have shown that HMGB1-induced autophagy exerts multiple functions in various cancers like proliferation. Moreover, inhibition of HMGB1-induced autophagy can reverse chemoresistance, which is regulated by noncoding RNAs such as microRNAs and lncRNAs. Here, we provide a brief introduction to HMGB1 and HMGB1-induced autophagy in cancer. We also discuss the challenges associated with performing further investigations on this issue. HMGB1-induced autophagy exerts significant functions in cancer and has potential utility for new strategy to reverse drug resistance.

Expression and significance of autophagy genes LC3, Beclin1 and MMP-2 in endometriosis

Expression of autophagy-related proteins, microtubule-associated protein light chain 3 (LC3) and Beclin1, and matrix metalloproteinase-2 (MMP-2) was investigated in serum and peritoneal fluid of patients with endometriosis (EM). The messenger ribonucleic acid (mRNA) expression levels of MMP-2, LC3 and Beclin1 in endometrial tissues of EM patients and correlation of these genes with EM and their significance were evaluated. The serum, peritoneal fluid and endometrial tissues of 84 patients treated in The First Affiliated Hospital of Qiqihar Medical University (Qiqihar, China) from March 2016 to March 2017 were collected. The serum, peritoneal fluid and endometrial tissues of 42 EM patients were used as the experimental group, while those of 42 non-EM patients were used as the control group. The levels of LC3, Beclin1 and MMP-2 in serum and peritoneal fluid of EM patients and non-EM patients were quantitatively detected via enzyme-linked immunosorbent assay (ELISA), followed by comparative analysis based on data in both groups. In addition, mRNA expression of LC3, Beclin1 and MMP-2 in the endometrium in both groups were detected via reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and differences in expression of these genes between the groups were analyzed and evaluated. Correlation of LC3, Beclin1 and MMP-2 with EM was explored. Results of ELISA showed that levels of LC3 and Beclin1 in the EM group were significantly lower than those in the control group, while levels of MMP-2 in serum and peritoneal fluid of the EM group were significantly higher than those in the control group (P<0.05). Results of RT-qPCR revealed that mRNA expression of LC3 and Beclin1 in the endometrium of patients in the EM group were obviously decreased compared with those in the control group, while the expression of MMP-2 was high, and differences in expression were statistically significant (P<0.05). The expression of MMP-2 is high, and expression of LC3 and Beclin1 is low in serum, peritoneal fluid and endometrium of EM patients, and investigating the expression of MMP-2, LC3 and Beclin1 in EM is helpful to further clarify the pathogenesis of EM, and guide the clinical diagnosis and treatment.