Age-associated disparity in phagocytic clearance affects the efficacy of cancer nanotherapeutics.

Nanomedicines have been approved to treat multiple human diseases. However, clinical adoption of nanoformulated agents is often hindered by concerns about hepatic uptake and clearance, a process that is not fully understood. Here we show that the antitumour efficacy of cancer nanomedicine exhibits an age-associated disparity. Tumour delivery and treatment outcomes are superior in old versus young mice, probably due to an age-related decline in the ability of hepatic phagocytes to take up and remove nanoparticles. Transcriptomic- and protein-level analysis at the single-cell and bulk levels reveals an age-associated decrease in the numbers of hepatic macrophages that express the scavenger receptor MARCO in mice, non-human primates and humans. Therapeutic blockade of MARCO is shown to decrease the phagocytic uptake of nanoparticles and improve the antitumour effect of clinically approved cancer nanotherapeutics in young but not aged mice. Together, these results reveal an age-associated disparity in the phagocytic clearance of nanotherapeutics that affects their antitumour response, thus providing a strong rationale for an age-appropriate approach to cancer nanomedicine.

Adaptive design of mRNA-loaded extracellular vesicles for targeted immunotherapy of cancer.

The recent success of mRNA therapeutics against pathogenic infections has increased interest in their use for other human diseases including cancer. However, the precise delivery of the genetic cargo to cells and tissues of interest remains challenging. Here, we show an adaptive strategy that enables the docking of different targeting ligands onto the surface of mRNA-loaded small extracellular vesicles (sEVs). This is achieved by using a microfluidic electroporation approach in which a combination of nano- and milli-second pulses produces large amounts of IFN-γ mRNA-loaded sEVs with CD64 overexpressed on their surface. The CD64 molecule serves as an adaptor to dock targeting ligands, such as anti-CD71 and anti-programmed cell death-ligand 1 (PD-L1) antibodies. The resulting immunogenic sEVs (imsEV) preferentially target glioblastoma cells and generate potent antitumour activities in vivo, including against tumours intrinsically resistant to immunotherapy. Together, these results provide an adaptive approach to engineering mRNA-loaded sEVs with targeting functionality and pave the way for their adoption in cancer immunotherapy applications.

Dual-Loaded Liposomes Tagged with Hyaluronic Acid Have Synergistic Effects in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is the most lethal subtypes of breast cancer. Although chemotherapy is considered the most effective strategy for TNBC, most chemotherapeutics in current use are cytotoxic, meaning they target antiproliferative activity but do not inhibit tumor cell metastasis. Here, a TNBC-specific targeted liposomal formulation of epalrestat (EPS) and doxorubicin (DOX) with synergistic effects on both tumor cell proliferation and metastasis is described. These liposomes are biocompatible and effectively target tumor cells owing to hyaluronic acid (HA) modification on their surface. This active targeting, mediated by CD44-HA interaction, allows DOX and EPS to be delivered simultaneously to tumor cells in vivo, where they suppress not only TNBC tumor growth and the epithelial-mesenchymal transition, but also cancer stem cells, which collectively suppress tumor growth and metastasis of TNBC and may also act to prevent relapse of TNBC.

Racial and Ethnic Differences in Genomic Profiling of Early Onset Colorectal Cancer.

The incidence and mortality of early onset colorectal cancer (EOCRC) is rising; outcomes appear to differ by race and ethnicity. We aimed to assess differences in mutational landscape and gene expression of EOCRC by racial and ethnic groups (non-Hispanic Asian, non-Hispanic Black, non-Hispanic White, White Hispanic) using data from the American Association for Cancer Research Project GENIE (10.2) and University of Texas Southwestern, the latter enriched in Hispanic patients. All statistical tests were 2-sided. Of 1752 EOCRC patients, non-Hispanic Black patients had higher rates of KRAS mutations (60.9%; P = .001, q = 0.015), and non-Hispanic White and non-Hispanic Black patients had higher rates of APC mutations (77.1% and 76.6% among non-Hispanic White and non-Hispanic Black patients, respectively; P = .001, q = 0.015) via the Fisher exact test with Benjamini-Hochberg correction. Using R packages DESeq2 and clusterProfiler, we found that White Hispanic patients had increased expression of genes involved in oxidative phosphorylation (P < .001, q = 0.025). Genomic profiling has the potential to identify novel diagnostics and influence individualized treatment options to address the currently limited prognosis of EOCRC.

Emerging Biological Functions of IL-17A: A New Target in Chronic Obstructive Pulmonary Disease?

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease that causes high rates of disability and mortality worldwide because of severe progressive and irreversible symptoms. During the period of COPD initiation and progression, the immune system triggers the activation of various immune cells, including Regulatory T cells (Tregs), dendritic cells (DCs) and Th17 cells, and also the release of many different cytokines and chemokines, such as IL-17A and TGF-ß. In recent years, studies have focused on the role of IL-17A in chronic inflammation process, which was found to play a highly critical role in facilitating COPD. Specially, IL-17A and its downstream regulators are potential therapeutic targets for COPD. We mainly focused on the possibility of IL-17A signaling pathways that involved in the progression of COPD; for instance, how IL-17A promotes airway remodeling in COPD? How IL-17A facilitates neutrophil inflammation in COPD? How IL-17A induces the expression of TSLP to promote the progression of COPD? Whether the mature DCs and Tregs participate in this process and how they cooperate with IL-17A to accelerate the development of COPD? And above associated studies could benefit clinical application of therapeutic targets of the disease. Moreover, four novel efficient therapies targeting IL-17A and other molecules for COPD are also concluded, such as Bufei Yishen formula (BYF), a Traditional Chinese Medicine (TCM), and curcumin, a natural polyphenol extracted from the root of Curcuma longa.

Assessment of Trends in Second Primary Cancers in Patients With Metastatic Melanoma From 2005 to 2016.

Importance: To date, the risk of developing second primary cancers (SPCs) after the first primary melanoma has not been studied in the era of immune checkpoint inhibitors (ICIs). Objective: To assess differences in the risk of SPCs in patients with primary melanoma before (2005-2010) and after (2011-2016) the introduction and approval of ICIs. Design, Setting, and Participants: Population-based cohort study using the Surveillance, Epidemiology, and End Results database from January 2005 to December 2016 of patients diagnosed with metastatic melanoma. Data were analyzed from January 4 to June 30, 2020. Exposures: Receipt of immunotherapy or other anticancer agents. Main Outcomes and Measures: The primary outcome was the development of second primary cancers in patients with melanoma. Standardized incidence ratios (SIRs) were calculated for the development of SPCs before and after the introduction of ICIs. Results: Among 5016 patients with diagnosed metastatic melanoma, 2888 (58%) were younger than 65 years at the time of diagnosis, and 3441 (69%) were male. From 2005 to 2010, SIRs were 3.24 (95% CI, 0.08-18.04) for small intestine cancer, 1.93 (95% CI, 1.14-3.05) for lung and bronchus cancer, 2.77 (95% CI, 1.02-6.03) for kidney cancer, and 7.29 (95% CI, 2.93-15.02) for myeloma. From 2011 to 2016, SIRs were 9.23 (95% CI, 1.12-33.35) for small intestine cancer, 1.54 (95% CI, 0.71-2.93) for lung and bronchus cancer, 2.66 (95% CI, 0.73-6.82) for kidney cancer, and 5.90 (95% CI, 1.61-15.10) for myeloma. The overall risk of developing SPCs in individuals who survived the first primary melanoma was 65% higher (SIR, 1.65; 95% CI, 1.35-2.00) in the pre-ICIs period and 98% higher (SIR, 1.98; 95% CI, 1.57-2.45) in the post-ICIs period than the overall cancer incidence rate in the general population. Conclusions and Relevance: In this study, an increase in the overall risk of second primary cancers after melanoma after the introduction of immune checkpoint inhibitors was observed. The pattern of SPCs has been altered in the era of systemic therapy. Close monitoring and screening for SPCs may be warranted in patients with metastatic melanoma.

Therapeutic modulation of phagocytosis in glioblastoma can activate both innate and adaptive antitumour immunity.

Tumour cell phagocytosis by antigen presenting cells (APCs) is critical to the generation of antitumour immunity. However, cancer cells can evade phagocytosis by upregulating anti-phagocytosis molecule CD47. Here, we show that CD47 blockade alone is inefficient in stimulating glioma cell phagocytosis. However, combining CD47 blockade with temozolomide results in a significant pro-phagocytosis effect due to the latter's ability to induce endoplasmic reticulum stress response. Increased tumour cell phagocytosis subsequently enhances antigen cross-presentation and activation of cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) in APCs, resulting in more efficient T cell priming. This bridging of innate and adaptive responses inhibits glioma growth, but also activates immune checkpoint. Sequential administration of an anti-PD1 antibody overcomes this potential adaptive resistance. Together, these findings reveal a dynamic relationship between innate and adaptive immune regulation in tumours and support further investigation of phagocytosis modulation as a strategy to enhance cancer immunotherapy responses.

Immunocyte Membrane-Coated Nanoparticles for Cancer Immunotherapy.

Despite the advances in surface bioconjugation of synthetic nanoparticles for targeted drug delivery, simple biological functionalization is still insufficient to replicate complex intercellular interactions naturally. Therefore, these foreign nanoparticles are inevitably exposed to the immune system, which results in phagocytosis by the reticuloendothelial system and thus, loss of their biological significance. Immunocyte membranes play a key role in intercellular interactions, and can protect foreign nanomaterials as a natural barrier. Therefore, biomimetic nanotechnology based on cell membranes has developed rapidly in recent years. This paper summarizes the development of immunocyte membrane-coated nanoparticles in the immunotherapy of tumors. We will introduce several immunocyte membrane-coated nanocarriers and review the challenges to their large-scale preparation and application.

Prognostic values of preoperative platelet-to-lymphocyte ratio and platelet-related indices in advanced hypopharyngeal squamous cell carcinoma.

OBJECTIVES: To investigate the prognostic values of preoperative platelet-to-lymphocyte ratio (PLR) and platelet-related indices in advanced hypopharyngeal squamous cell carcinoma (HPSCC). METHODS: The data of 247 eligible advanced HPSCC patients were reviewed retrospectively. Pretreatment haematological parameters were categorised into two groups based on the result of X-tile, and several variates were assessed using chi-square test, Kaplan-Meier method, Cox univariate and multivariate analysis. RESULTS: The optimal cut-off points of 171.4 for PLR, 260 × 109 /L for platelet, 10.4 fL for mean platelet volume (MPV) and 16.5% for platelet distribution width were defined. The haematological parameters PLR and MPV, postoperative metastasis and internal jugular vein invasion were statistically significant in OS and DFS analyses (P < .05). The high PLR (>171.4) or high MPV (>10.4 fL) was significantly associated with worse OS and DFS (P < .05). CONCLUSIONS: The preoperative levels of PLR and MPV could be considered as independent prognostic predictors in patients with advanced HPSCC.

Large-scale generation of functional mRNA-encapsulating exosomes via cellular nanoporation.

Exosomes are attractive as nucleic-acid carriers because of their favourable pharmacokinetic and immunological properties and their ability to penetrate physiological barriers that are impermeable to synthetic drug-delivery vehicles. However, inserting exogenous nucleic acids, especially large messenger RNAs, into cell-secreted exosomes leads to low yields. Here we report a cellular-nanoporation method for the production of large quantities of exosomes containing therapeutic mRNAs and targeting peptides. We transfected various source cells with plasmid DNAs and stimulated the cells with a focal and transient electrical stimulus that promotes the release of exosomes carrying transcribed mRNAs and targeting peptides. Compared with bulk electroporation and other exosome-production strategies, cellular nanoporation produced up to 50-fold more exosomes and a more than 103-fold increase in exosomal mRNA transcripts, even from cells with low basal levels of exosome secretion. In orthotopic phosphatase and tensin homologue (PTEN)-deficient glioma mouse models, mRNA-containing exosomes restored tumour-suppressor function, enhanced inhibition of tumour growth and increased survival. Cellular nanoporation may enable the use of exosomes as a universal nucleic-acid carrier for applications requiring transcriptional manipulation.

Low-Dose Anti-Angiogenic Therapy Sensitizes Breast Cancer to PD-1 Blockade.

PURPOSE: Despite its enormous successes, the overall response rate of cancer immunotherapy remains suboptimal, especially in breast cancer. There is an increased interest in combining immune checkpoint inhibitor with targeted agents to enhance antitumor effect. Anti-angiogenic drugs have been shown to synergize with immune checkpoint blockades, but the optimal setting for combining these two modalities and the underlying mechanisms of synergistic responses are not fully understood. EXPERIMENTAL DESIGN: We tested the combination of anti-PD-1 and different doses of VEGFR2-targeting agents in syngeneic breast cancer mouse models. Tumor-infiltrated immune cell subsets were profiled by flow cytometry. A cytokine array was carried out to identify inflammatory changes in different treatment conditions. The efficacy of combined anti-angiogenic and anti-PD-1 therapy was further evaluated in patients with advanced triple-negative breast cancer (TNBC). RESULTS: Blockade of VEGFR2 sensitizes breast tumors to PD-1 blockade in a dose-dependent manner. Although both conventional and low-dose anti-VEGFR2 antibody treatments normalize tumor vessels, low-dose VEGFR2 blockade results in more robust immune cell infiltration and activation and promotes the secretion of osteopontin (OPN) by CD8+ T cells. OPN subsequently induces tumor cell production of TGF-ß, which in turn upregulates PD-1 expression on immune cells. In patients with advanced TNBC, combined treatment with low-dose anti-VEGFR2 inhibitor and anti-PD-1 demonstrated excellent tolerability and efficacy. Higher OPN and TGF-ß expressions correlated with improved treatment responses. CONCLUSIONS: Together, these results demonstrate a dose-dependent synergism between anti-angiogenic therapy and immune checkpoint blockade, thus providing important insights into the optimal strategies for combining immunotherapy with molecular-targeted agents.

Clinical outcome and comparison between squamous and non-squamous cell carcinoma of the larynx.

Background: The various pathological types of non-squamous cell carcinomas (nSCCs) of the larynx accounted for about 5% laryngeal malignancies, but the knowledge regarding these pathological behaviors, therapeutic models and prognostic factors was limited.Objectives: To investigate the clinical characteristics and the survival outcomes of nSCCs of the larynx.Material and methods: A total of 106 patients diagnosed with laryngeal nSCC between 2003 and 2014 were retrospectively investigated from a cohort of 4,796 patients with laryngeal malignancies.Results: Spindle cell carcinoma, malignant salivary gland carcinoma, neuroendocrine carcinoma, non-Hodgkin's lymphomas, and carcinosarcoma accounted for the majority of the nSCCs of the larynx. In laryngeal nSCCs (excluding non-Hodgkin lymphomas), there was no significant difference in overall survival (OS) by tumor subsite (p = .818), clinical-stage (p = .051) or T stage (p = .412), but the difference in OS by N stage was statistically significant (p = .001). Upon comparison of propensity score-matched groups, the OS was longer in SCCs of the larynx (p = .0004).Conclusions and significance: Primary nSCC of the larynx is rare, and its diagnosis depends on comprehensive immunohistochemical examination, as the clinical characteristics are non-specific compared with SCC. The overall prognosis of nSCC is relatively poor compared with that of SCC in the larynx.

Folate Receptor-Targeted Albumin Nanoparticles Based on Microfluidic Technology to Deliver Cabazitaxel.

Microfluidic technology (MF) has improved the formulation of nanoparticles (NPs) by achieving uniform particle size distribution, controllable particle size, and consistency. Moreover, because liquid mixing can be precisely controlled in the pores of the microfluidic chip, maintaining high mixing efficiency, MF exerts higher of NP encapsulation efficiency (EE) than conventional methods. MF-NPs-cabazitaxel (CTX) particles (MF-NPs-CTX) were first prepared by encapsulating CTX according to MF. Folate (FA)- Polyethylene glycol (PEG)-NPs-CTX particles (FA-PEG-NPs-CTX) were formulated by connecting FA to MF-NPs-CTX to endow NPs with targeted delivery capability. Accordingly, the mean particle size of FA-PEG-NPs-CTX increased by approximately 25 nm, as compared with MF-NPs-CTX. Upon morphological observation of FA-PEG-NPs-CTX and MF-NPs-CTX by transmission electron microscopy (TEM), all NPs were spherical and particle size distribution was uniform. Moreover, the increased delivery efficiency of CTX in vitro and its strong tumor inhibition in vivo indicated that FA-PEG-NPs-CTX had a powerful tumor-suppressive effect both in vitro and in vivo. In vivo imaging and pharmacokinetic data confirmed that FA-PEG-NPs-CTX had good drug delivery efficiency. Taken together, FA-PEG-NPs-CTX particles prepared using MF showed high efficient and targeted drug delivery and may have a considerable driving effect on the clinical application of targeting albumin NPs.

Tankyrase disrupts metabolic homeostasis and promotes tumorigenesis by inhibiting LKB1-AMPK signalling.

The LKB1/AMPK pathway plays a major role in cellular homeostasis and tumor suppression. Down-regulation of LKB1/AMPK occurs in several human cancers and has been implicated in metabolic diseases. However, the precise upstream regulation of LKB1-AMPK pathway is largely unknown. Here, we report that AMPK activation by LKB1 is regulated by tankyrases. Tankyrases interact with and ribosylate LKB1, promoting its K63-linked ubiquitination by an E3 ligase RNF146, which blocks LKB1/STRAD/MO25 complex formation and LKB1 activation. LKB1 activation by tankyrase inhibitors induces AMPK activation and suppresses tumorigenesis. Similarly, the tankyrase inhibitor G007-LK effectively regulates liver metabolism and glycemic control in diabetic mice in a LKB1-dependent manner. In patients with lung cancer, tankyrase levels negatively correlate with p-AMPK levels and poor survival. Taken together, these findings suggest that tankyrase and RNF146 are major up-stream regulators of LKB1-AMPK pathway and provide another focus for cancer and metabolic disease therapies.

FSCN1 is an effective marker of poor prognosis and a potential therapeutic target in human tongue squamous cell carcinoma.

To estimate the value of FSCN1 in evaluating the prognosis and guiding the targeted therapy for patients with tongue squamous cell carcinoma (TSCC). Using the Oncomine database, we found some genes especially FSCN1 differentially expressed between TSCC samples and tongue normal samples. So we compared FSCN1 expression between TSCC and normal cell lines and knocked down FSCN1 in TSCC cells to observe its influence on the viability and trans-migration in vitro and tumor growth in vivo. Then we measured FSCN1 expression in human cancer tissues and adjacent non-carcinoma tissues (ANT) and explored the relationship between FSCN1 expression and clinical pathological factors and prognosis in TSCC patients. We found that FSCN1 is expressed higher in TSCC cells than in normal cells. Knockdown of FSCN1 reduced TSCC cell viability and trans-migration in vitro and impaired tumor growth in vivo. FSCN1 also expressed higher in human TSCC than in ANT. In addition, FSCN1 expression was related to N classification, clinical stage and relapse. TSCC patients with over-expression of FSCN1 had worse prognosis. In conclusion, over-expression of FSCN1 indicates worse prognosis for patients with TSCC and FSCN1 may be a potential prognostic biomarker and therapeutic target in TSCC.

The relationship of lymphocyte recovery and prognosis of esophageal cancer patients with severe radiation-induced lymphopenia after chemoradiation therapy.

INTRODUCTION: Radiation-induced lymphopenia (RIL) during therapy is associated with poor prognosis but is often temporary and resolves after treatment completion in esophageal cancer. How lymphocyte recovery contributes to prognosis is unknown. METHODS: We reviewed 755 patients with stage I-III esophageal carcinoma who received concurrent chemoradiation therapy (CRT) with or without surgery in 2004-2015. Complete blood counts were obtained before, during, and at first follow-up after CRT. Lymphopenia was graded per the Common Terminology Criteria for Adverse Events v4.03 during CRT (G) and as recovery after CRT (Gr). Clinical factors and lymphopenia grade were tested for association with survival in univariable and multivariable Cox proportional hazard regression analyses. RESULTS: During CRT, 294 patients (38.9%) had G4 lymphopenia; by the first follow-up, 406 patients (53.8%) had recovered (Gr0-1). Relative to patients with G0-3 lymphopenia during CRT, G4 lymphopenia independently predicted worse OS in multivariable analyses. However, lymphocyte recovery was not associated with a better prognosis. Patients with G4 lymphopenia during CRT and recovery (Gr0-1) afterward still had poorer 5-year OS rate than patients with G0-3 during CRT without recovery (Gr2-4) afterward (36.6% vs. 51.9%, HR = 1.40, 95% CI 1.04-1.89, P = 0.027). Moreover, the lymphocyte recovery ability (post-CRT ALC divided by pre-CRT ALC) was not affected by lymphopenia grade during CRT (0.66 in G0-3 vs. 0.65 in G4, p = 0.473). Among patients with G4 lymphopenia during treatment, lymphocyte recovery was only associated with pre-CRT lymphocyte counts. CONCLUSION: Lymphocyte count recovery after CRT does not alter the poor long-term outcomes brought about by high-grade lymphopenia during CRT.

Clinical effect of postoperative chemoradiotherapy in resected advanced laryngeal squamous cell carcinoma.

Laryngeal squamous cell carcinoma (LSCC) is one of the most prevalent types of head and neck malignancies. Advanced LSCC has failed to demonstrate a satisfactory prognosis, despite the progresses in the diagnosis and treatment, and the optimal treatment modality continues to be debated. To evaluate the clinical utility and survival outcomes of adjuvant chemoradiotherapy (CRT) for patients with resected advanced LSCC, a retrospective analysis of 232 patients with LSCC who had undergone total laryngectomy and neck dissection between 2005 and 2010 was conducted. Of the 232 eligible patients, 167 patients (72%) received surgery alone, whereas 65 patients (28%) received surgery + adjuvant CRT. In the overall cohort, the 5- and 10-year overall survival (OS) rates were 55.2 and 48.3%, respectively. Multivariate analysis revealed that the clinical stage was significantly associated with OS. However, the N classification was an independent indicator in disease-free survival and laryngeal cancer-specific survival. In those patients with stage IV disease, patients receiving adjuvant CRT exhibited a markedly improved survival benefit compared with patients receiving surgical treatment only, following propensity score matching of the data (P<0.05). The application of adjuvant CRT confers additional survival benefits in comparison with surgery-only treatment regimens for advanced LSCC. However, additional prospective studies are required.

Patterns of Local-Regional Failure After Intensity Modulated Radiation Therapy or Passive Scattering Proton Therapy With Concurrent Chemotherapy for Non-Small Cell Lung Cancer.

PURPOSE: We compared differences in patterns of locoregional failure, and the influence of adaptive planning on those patterns, in patients who received passive scattering proton therapy (PSPT) versus intensity modulated photon therapy (IMRT) for non-small cell lung cancer. METHODS AND MATERIALS: Treatment simulation computed tomography scans and dose distributions were registered with images depicting the recurrence. Local failure (LF) was defined as failure within the internal target volume (ITV); marginal failure (MF) as failure between the ITV and planning target volume (PTV) plus a 10-mm margin (PTV+10mm); and regional failure (RF) as outside the PTV+10mm. Weekly during-treatment 4-dimensional computed tomography simulation and verification plans were obtained for all patients. Adaptive plans were developed if the verification plan showed deviations in protocol-specified dose distribution, and failure locations were recorded for those patients as well. RESULTS: Of the 212 patients analyzed, most (152 [72%]) had no failure; of the 60 patients with failure, 27 (45%) had LF (within the ITV), 23 (38%) had MF (between the ITV and PTV+10mm), and 10 (17%) had RF (>10 mm outside the PTV). MF rates were no different for IMRT patients (16 of 136 [12%]) or PSPT patients (7 of 76 [9%], log-rank P = .558). The only independent predictor of MF on Cox proportional hazards analysis was T3-4 status. Large tumors and use of PSPT independently predicted the need for adaptive planning. Although 5-year overall survival rates were poorer for patients with large tumors versus small tumors (P < .001), the rates were similar for patients with large tumors who received adaptive planning versus small tumors. CONCLUSIONS: No differences in LF, MF, or RF patterns were found for IMRT versus PSPT. Proton therapy more often required adaptive planning, and the techniques used for adaptive planning did not compromise tumor control. Response to chemoradiation by larger tumors predicted favorable survival.

Poly (ADP-Ribose) Polymerases (PARPs) and PARP Inhibitor-Targeted Therapeutics.

BACKGROUND: Poly-ADP-ribosylation, that is, adding ADP-ribose moieties to a protein, is a unique type of protein post-translational modification that regulates various cellular processes such as DNA repair, mitosis, transcription, and cell growth. Small-molecule inhibitors of poly-ADP-ribose polymerase 1 (PARP1) have been developed as anticancer agents because inhibition of PARP enzymes may be a synthetic lethal strategy for cancers with or BRCA2 mutations. However, there are still questions surrounding PARP inhibitors. METHODS/RESULTS: Data were collected from Pubmed, Medline, through searching of these keywords: "PARP", "BRCA", "Synthetic lethal" and "Tankyrase inhibitors". We describe the current knowledge of PARP inhibition and its effects on DNA damage; mechanisms of resistance to PARP inhibitors; the evolution of PARP inhibitors; and the potential use of PARP5a/b (tankyrases) inhibitors in cancer treatment. CONCLUSION: PARP inhibitors are already showing promise as therapeutic tools, especially in the management of BRCA-mutated breast and ovarian cancers but also in tumors with dysfunctional BRCA genes. Small-molecule tankyrase inhibitors are important for increasing our understanding of tankyrase biology.

The Reciprocity between Radiotherapy and Cancer Immunotherapy.

The clinical success of immune checkpoint inhibitors in treating metastatic and refractory cancers has generated significant interest in investigating their role in treating locally advanced diseases, thus requiring them to be combined with standard treatments in the hope of producing synergistic antitumor responses. Radiotherapy, in particular, has long been hypothesized to have actions complementary to those of immune checkpoint blockade, and a growing body of evidence indicates that cancer immunotherapy may also have radiosensitizing effects, which would provide unique benefit for locoregional treatments. Recent studies have demonstrated that when immune cells are activated by immunotherapeutics, they can reprogram the tumor microenvironment in ways that may potentially increase the radiosensitivity of the tumor. In this review, we highlight the evidence that supports reciprocal interactions between cancer immunotherapy and radiotherapy, where in addition to the traditional notion that radiation serves to enhance the activation of antitumor immunity, an alternative scenario also exists in which T-cell activation by cancer immunotherapy may sensitize tumors to radiation treatment through mechanisms that include normalization of the tumor vasculature and tissue hypoxia. We describe the empirical observations from preclinical models that support such effects and discuss their implications for future research and trial design.