A Population-based Model of Local Control and Survival Benefit of Radiotherapy for Lung Cancer

Hypofractionated Radiotherapy in Gynecologic Malignancies-A Peek into the Upcoming Evidence

Radiotherapy (RT) has a fundamental role in the treatment of gynecologic malignancies, including cervical and uterine cancers. Hypofractionated RT has gained popularity in many cancer sites, boosted by technological advances in treatment delivery and image verification. Hypofractionated RT uptake was intensified during the COVID-19 pandemic and has the potential to improve universal access to radiotherapy worldwide, especially in low-resource settings. This review summarizes the rationale, the current challenges and investigation efforts, together with the recent developments associated with hypofractionated RT in gynecologic malignancies. A comprehensive search was undertaken using multiple databases and ongoing trial registries. In the definitive radiotherapy setting for cervical cancers, there are several ongoing clinical trials from Canada, Mexico, Iran, the Philippines and Thailand investigating the role of a moderate hypofractionated external beam RT regimen in the low-risk locally advanced population. Likewise, there are ongoing ultra and moderate hypofractionated RT trials in the uterine cancer setting. One Canadian prospective trial of stereotactic hypofractionated adjuvant RT for uterine cancer patients suggested a good tolerance to this treatment strategy in the acute setting, with a follow-up trial currently randomizing patients between conventional fractionation and the hypofractionated dose regimen delivered in the former trial. Although not yet ready for prime-time use, hypofractionated RT could be a potential solution to several challenges that limit access to and the utilization of radiotherapy for gynecologic cancer patients worldwide.

Extracellular vesicle-mediated ferroptosis, pyroptosis, and necroptosis: potential clinical applications in cancer therapy

Extracellular vesicles (EVs) have gained increasing recognition as significant regulators of intercellular communication in various physiological and pathological processes. These vesicles play a pivotal role in cancer progression by facilitating the transfer of diverse cargoes, including lipids, proteins, and nucleic acids. Regulated cell death (RCD), the orderly and autonomous death of cells, is controlled by a variety of biomacromolecules and, in turn, influences various biological processes and cancer progression. Recent studies have demonstrated that EV cargoes regulate diverse oncogenes and tumor suppressors to mediate different nonapoptotic forms of RCD, notably ferroptosis, pyroptosis, and necroptosis. Nevertheless, comprehensive exploration of EV-mediated nonapoptotic RCD forms in the context of cancer has not been performed. This review summarizes the progress regarding the biological functions and underlying mechanisms of EVs in mediating nonapoptotic RCD by delivery of cargoes to regulate tumor progression. Additionally, the review delves into the potential clinical applications of EV-mediated cell death and its significance in the areas of cancer diagnosis and therapy.

Hospital factors determining overall survival in cancer patients undergoing curative treatment

BACKGROUND

In oncology, overall survival (OS) and quality of life (QoL) are key indicators. The factors that affect OS and QoL include tumor-related characteristics (stage and grade), patient-related factors (performance status and comorbidities), and cancer-directed therapy (CDT)-related aspects. In addition, external factors such as governance or policy (e.g., inaccessibility to CDT, increased distance to service, poor socioeconomic status, lack of insurance), and hospital-related factors (e.g., facility volume and surgeon volume) can influence OS and QoL.

MATERIALS AND METHODS

The primary objective of this narrative review was to identify hospital-related factors that affect OS and QoL in patients receiving curative CDT. The authors defined extrinsic factors that can be modified at the hospital level as "hospital-related" factors. Only factors supported by randomized controlled trials (RCT), systematic reviews (SR) and/or meta-analyses (MA), and population database (PDB) analyses that address the relationship between OS and hospital factors were considered.

RESULTS

The literature review found that high hospital or oncologist volume, adherence to evidence-based medicine (EBM), optimal time-to-treatment initiation (TTI), and decreased overall treatment time (OTT) increase OS in patients undergoing curative CDT. The use of case management strategies was associated with better symptom management and treatment compliance, but had a mixed effect on QoL. The practice of enhanced recovery after surgery (ERAS) in cancer patients did not result in an increase in OS. There was insufficient evidence to support the impact of factors such as teaching or academic centers, hospital infrastructure, and treatment compliance on OS and QoL.

CONCLUSION

The authors conclude that hospital policies should focus on increasing hospital and oncologist volume, adhering to EBM, optimizing TTI, and reducing OTT for cancer patients receiving curative treatment.

Rates of adherence to cancer treatment guidelines in Australia and the factors associated with adherence: A systematic review

Adherence to cancer treatment clinical practice guidelines (CPGs) varies enormously across Australia, despite being associated with improved patient outcomes. This systematic review aims to characterize adherence rates to active-cancer treatment CPGs in Australia and related factors to inform future implementation strategies. Five databases were systematically searched, abstracts were screened for eligibility, a full-text review and critical appraisal of eligible studies performed, and data extracted. A narrative synthesis of factors associated with adherence was conducted, and the median adherence rates within cancer streams calculated. A total of 21,031 abstracts were identified. After duplicates were removed, abstracts screened, and full texts reviewed, 20 studies focused on adherence to active-cancer treatment CPGs were included. Overall adherence rates ranged from 29% to 100%. Receipt of guideline recommended treatments was higher for patients who were younger (diffuse large B-cell lymphoma [DLBCL], colorectal, lung, and breast cancer); female (breast and lung cancer), and male (DLBCL and colorectal cancer); never smokers (DLBCL and lung cancer); non-Indigenous Australians (cervical and lung cancer); with less advanced stage disease (colorectal, lung, and cervical cancer), without comorbidities (DLBCL, colorectal, and lung cancer); with good-excellent Eastern Cooperative Oncology Group performance status (lung cancer); living in moderately accessible places (colon cancer); and; treated in metropolitan facilities (DLBLC, breast and colon cancer). This review characterized active-cancer treatment CPG adherence rates and associated factors in Australia. Future targeted CPG implementation strategies should account for these factors, to redress unwarranted variation particularly in vulnerable populations, and improve patient outcomes (Prospero number: CRD42020222962).

Ginsenoside Rg5 enhances the radiosensitivity of lung adenocarcinoma via reducing HSP90-CDC37 interaction and promoting client protein degradation

Ginsenoside Rg5 is a rare ginsenoside showing promising tumor-suppressive effects. This study aimed to explore its radio-sensitizing effects and the underlying mechanisms. Human lung adenocarcinoma cell lines A549 and Calu-3 were used for in vitro and in vivo analysis. Bioinformatic molecular docking prediction and following validation by surface plasmon resonance (SPR) technology, cellular thermal shift assay (CETSA), and isothermal titration calorimetry (ITC) were conducted to explore the binding between ginsenoside Rg5 and 90 kD heat shock protein alpha (HSP90α). The effects of ginsenoside Rg5 on HSP90-cell division cycle 37 (CDC37) interaction, the client protein stability, and the downstream regulations were further explored. Results showed that ginsenoside Rg5 could induce cell-cycle arrest at the G1 phase and enhance irradiation-induced cell apoptosis. It could bind to HSP90α with a high affinity, but the affinity was drastically decreased by HSP90α Y61A mutation. Co-immunoprecipitation (Co-IP) and ITC assays confirmed that ginsenoside Rg5 disrupts the HSP90-CDC37 interaction in a dose-dependent manner. It reduced irradiation-induced upregulation of the HSP90-CDC37 client proteins, including SRC, CDK4, RAF1, and ULK1 in A549 cell-derived xenograft (CDX) tumors. Ginsenoside Rg5 or MRT67307 (an IKKε/TBK1 inhibitor) pretreatment suppressed irradiation-induced elevation of the LC3-II/β ratio and restored irradiation-induced downregulation of p62 expression. In A549 CDX tumors, ginsenoside Rg5 treatment suppressed LC3 expression and enhanced irradiation-induced DNA damage. In conclusion, ginsenoside Rg5 may be a potential radiosensitizer for lung adenocarcinoma. It interacts with HSP90α and reduces the binding between HSP90 and CDC37, thereby increasing the ubiquitin-mediated proteasomal degradation of the HSP90-CDC37 client proteins.

Association between radiotherapy and risk of second primary malignancies in patients with resectable lung cancer: a population-based study

BACKGROUND

The most common form of treatment for non-metastatic lung cancer is surgery-based combination therapy, which may also include adjuvant radiotherapy or chemotherapy. Second primary malignancies (SPMs) are uncommon but significant radiation side effects in patients with resectable lung cancer, and SPMs have not been adequately investigated. Our study aims to assess the correlations of radiotherapy with the development of SPMs in patients with resectable lung cancer.

METHODS

We screened for any primary malignancy that occurred more than five years after the diagnosis of resectable lung cancer. Based on the large cohort of the Surveillance, Epidemiology and End Results database, radiotherapy-correlated risks were estimated using the Poisson regression analysis and the cumulative incidence of SPMs was calculated using Fine-Gray competing risk regression analysis.

RESULTS

Among the 62,435 patients with non-metastatic lung cancer undergoing surgery, a total of 11,341 (18.16%) patients have received radiotherapy. Our findings indicated that radiotherapy was substantially related to a high risk of main second solid malignancies (RR = 1.21; 95%CI, 1.08 to 1.35) and a negligible risk of main second hematologic malignancies (RR = 1.08; 95%CI, 0.84 to 1.37). With the greatest number of patients, the risk of acquiring a second primary gastrointestinal cancer was the highest overall (RR = 1.77; 95 percent CI, 1.44 to 2.15). The cumulative incidence and standardized incidence ratios of SPMs revealed similar findings. Furthermore, the young and the elderly may be more vulnerable, and the highest risk of acquiring most SPMs was seen more than ten years after lung cancer diagnosis. Additionally, more attention should be paid to the second primary gastrointestinal cancer in young individuals with resectable lung cancer.

CONCLUSION

After receiving radiotherapy, an increased risk of developing second primary solid and gastrointestinal cancers was observed for patients with resectable lung cancer. The prevention of SPMs associated with radiotherapy requires further attention.

Ginsenoside Rg3 enhances the radiosensitivity of lung cancer A549 and H1299 cells via the PI3K/AKT signaling pathway

Lung cancer is one of the most common cancers and the leading cause of cancer-related deaths in the world. Radiation is widely used for the treatment of lung cancer. However, radioresistance and toxicity limit its effectiveness. Ginsenoside Rg3 (Rg3) is a positive monomer extracted from ginseng and has been shown to the anti-cancer ability on many tumors. The aim of the present study was to ascertain whether Rg3 is able to enhance the radiosensitivity of lung cancer cells and investigate the underlying mechanisms. The effect of Rg3 on cell proliferation was examined by Cell Counting Kit-8 (CCK-8) and radiosensitivity was measured by colony formation assay. Flow cytometry, transwell, and wound healing assay were used to determine apoptosis, cell cycle, and metastasis. Western blot was used to detect the main protein levels of the PI3K/AKT signaling pathway. We found that Rg3 inhibited cell proliferation, promoted apoptosis, and suppressed migration and invasion in radio-induced lung cancer cells. In addition, Rg3 increased the proportion of G2/M phase cells and inhibited the formation of cell colonies. Moreover, Rg3 decreased the expression levels of PI3K, p-AKT, and PDK1 in radio-induced cells. These findings indicate that Rg3 may be able to enhance the radiosensitivity in lung cancer cells by the PI3K/AKT signaling pathway. These results demonstrate the therapeutic potential of Rg3 as a radiosensitizer for lung cancer.

Radiosensitization-Related Cuproptosis LncRNA Signature in Non-Small Cell Lung Cancer

A new treatment modality targeting cuproptosis is gradually entering the public horizon. Cuproptosis is a new form of regulated cell death distinct from ferroptosis, apoptosis, autophagy, and necrosis. Previous studies have discovered that the copper level varies considerably in various cancers and that an increase in copper content is directly associated with the proliferation and metastasis of cancer cells. In non-small cell lung cancer (NSCLC) after radiation, the potential utility of cuproptosis-related long noncoding RNAs (lncRNAs) is still unclear. This research aimed to develop a prediction signature based on lncRNAs associated with cuproptosis to predict the prognosis of NSCLC patients following radiation. Methods: Expression data of primary tumors and adjacent solid tissues were downloaded from The Cancer Genome Atlas (TCGA) database, along with the corresponding clinical and mutational data. Univariate and multivariate COX analyses and LASSO regression analyses were performed to obtain a predictive signature of lncRNAs associated with cuproptosis. The data were randomly grouped into a training group used for model construction and a test group used for model validation. The model was validated by drawing a survival curve, risk curve, independent prognostic analysis, ROC curve PFS analysis, etc. Results: The lncRNA signature consisting of six cuproptosis-related lncRNAs (AC104088.1, PPP4R3B-DT, AC006042.3, LUCAT1, HHLA3-AS1, and LINC02029) was used to predict the prognosis of patients. Among them, there were three high-risk lncRNAs (LUCAT1, HHLA3-AS1, and LINC02029) with HR > 1 and three protective lncRNAs (AC104088.1, PPP4R3B-DT, and AC006042.3), with an HR < 1. Data analysis demonstrated that the cuproptosis-related lncRNA signatures could well predict the prognosis of NSCLC patients after radiation. Patients in the high-risk category receive a worse prognosis than those in the low-risk group. Cuproptosis-related risk prediction demonstrated better predictive qualities than age, gender, and pathological stage factors. Conclusion: The risk proposed model can independently predict the prognosis of NSCLC patients after radiotherapy, provide a foundation for the role of cuproptosis-related lncRNAs in NSCLC after radiotherapy, and provide a clinical strategy for radiotherapy combined with cuproptosis in NSCLC patients.

Radiotherapy utilisation rates for patients with cancer as a function of age: A systematic review

INTRODUCTION

There is an increasing incidence of cancer in older people, but limited data on radiotherapy uptake, and in particular, radiotherapy utilisation (RTU) rates. The RTU rate for older adults with cancer may be lower than recommended due to lower tolerance for radiotherapy as well as additional comorbidities, reduced life expectancy and travel for treatment. Radiotherapy use must be aligned with best available, age-specific evidence to ensure older adults with cancer receive optimal benefit without harms.

MATERIALS AND METHODS

A systematic review was conducted to synthesise the published data on the actual RTU rate for patients with cancer as a function of age. MEDLINE and EMBASE were systematically searched to identify relevant population-based and hospital-based cohort studies on radiotherapy utilisation for all age groups, published in English, from 1 January 1990 to 1 July 2020. We focused on the following common cancers in older adults for which radiotherapy is recommended: breast, prostate, lung, rectal cancer, glioblastoma multiforme (GBM), and cervical cancer. Age-specific radiotherapy utilisation data were extracted and analysed as a narrative synthesis.

RESULTS

From 2606 studies screened, 75 cohort and population-based studies were identified with age-specific radiotherapy utilisation data. The total number of patients in the 75 studies was 4,792,138. The RTU rate decreased with increasing age for all tumour sites analysed, except for patients receiving curative radiotherapy as definitive treatment for prostate or cervical cancer. This reduction with increasing age was demonstrated in both palliative and curative settings.

DISCUSSION

There is a global reduction in radiotherapy utilisation with increasing age for most tumour sites. The reduction in delivery of radiotherapy warrants further examination and evidence-based guidelines specific to this population.

Exosomal protein angiopoietin-like 4 mediated radioresistance of lung cancer by inhibiting ferroptosis under hypoxic microenvironment

BACKGROUND

Hypoxia-mediated radioresistance is a major reason for the adverse radiotherapy outcome of non-small cell lung cancer (NSCLC) in clinical, but the underlying molecular mechanisms are still obscure.

METHODS

Cellular and exosomal ANGPTL4 proteins under different oxygen status were examined. Colony survival, lipid peroxidation and hallmark proteins were employed to determine the correlation between ferroptosis and radioresistance. Gene regulations, western blot and xenograft models were used to explore the underlying mechanisms of the role of ANGPTL4 in radioresistance.

RESULTS

ANGPTL4 had a much higher level in hypoxic NSCLC cells compared to normoxic cells. Up- or down- regulation of ANGPTL4 positively interrelated to the radioresistance of NSCLC cells and xenograft tumours. GPX4-elicited ferroptosis suppression and lipid peroxidation decrease were authenticated to be involved in the hypoxia-induced radioresistance. ANGPTL4 encapsulated in the exosomes from hypoxic cells was absorbed by neighbouring normoxic cells, resulting in radioresistance of these bystander cells in a GPX4-dependent manner, which was diminished when ANGPTL4 was downregulated in the donor exosomes.

CONCLUSION

Hypoxia-induced ANGPTL4 rendered radioresistance of NSCLC through at least two parallel pathways of intracellular ANGPTL4 and exosomal ANGPTL4, suggesting that ANGPTL4 might applicable as a therapeutic target to improve the therapeutic efficacy of NSCLC.

Dihydroartemisinin Reduces Irradiation-Induced Mitophagy and Radioresistance in Lung Cancer A549 Cells via CIRBP Inhibition

Radiotherapy is a major therapeutic strategy for lung cancer, and radiation resistance (radioresistance) is an important cause of residual and recurring cancer after treatment. However, the mechanism of radioresistance remains unclear. Mitochondrial autophagy (mitophagy), an important selective autophagy, plays an important role in maintaining cell homeostasis and affects the response to therapy. Recent studies have shown that dihydroartemisinin (DHA), a derivative of artemisinin, can increase the sensitivity to treatment in multiple types of cancer, including lung cancer. The purpose of this study was to elucidate the function and molecular mechanisms of DHA-regulating mitophagy and DHA-reducing radioresistance in lung cancer A549 cells. We first constructed the radioresistant lung cancer A549 cells model (A549R) through fractional radiation, then elucidated the function and mechanism of DHA-regulating mitophagy to reduce the radioresistance of lung cancer by genomic, proteomic, and bioinformatic methods. The results showed that fractional radiation can significantly induce radioresistance and mitophagy in A549 cells, DHA can reduce mitophagy and radioresistance, and the inhibition of mitophagy can reduce radioresistance. Protein chip assay and bioinformatics analysis showed the following: Cold-Inducible RNA Binding Protein (CIRBP) might be a potential target of DHA-regulating mitophagy; CIRBP is highly expressed in A549R cells; the knockdown of CIRBP increases the effect of DHA, reduces mitophagy and radioresistance, and inhibits the mitophagy-related PINK1/Parkin pathway. In conclusion, we believe that DHA reduces radiation-induced mitophagy and radioresistance of lung cancer A549 cells via CIRBP inhibition.

Exosomal non-coding RNAs: Emerging roles in bilateral communication between cancer cells and macrophages

The tumor microenvironment (TME) is a dynamic network of cellular organization that comprises diverse cell types and significantly contributes to cancer development. As pivotal immune stromal cells in the TME, macrophages are extensively heterogeneous and exert both antitumor and protumor functions. Exosomes are nanosized extracellular membranous vesicles with diameters between 30 and 150 nm. By transferring multiple bioactive substances such as proteins, lipids, and nucleic acids, exosomes play an important role in the communication between cells. Recently, growing evidence has demonstrated that non-coding RNAs (ncRNAs) are enriched in exosomes and that exosomal ncRNAs are involved in the crosstalk between cancer cells and macrophages. Furthermore, circulating exosomal ncRNAs can be detected in biofluids, serving as promising noninvasive biomarkers for the early diagnosis and prognostic prediction of cancer. Exosome-based therapies are emerging as potent strategies that can be utilized to alleviate tumor progression. Herein, the present knowledge of exosomal ncRNAs and their vital roles in regulating the interplay between cancer cells and macrophages, as well as their clinical applications are summarized.

Optimal and actual rates of Stereotactic Ablative Body Radiotherapy (SABR) utilisation for primary lung cancer in Australia

•

Stereotactic Ablative Body Radiotherapy (SABR) plays a major role in the management of early-stage non-small cell lung cancer (NSCLC).

•

An evidence-based model is developed to estimate optimal rates of lung SABR utilisation within the Australian population.

•

Optimal utilisation rates are compared against actual utilisation rates to evaluate service provision.

Background and purpose

Radiotherapy utilisation rates considerably vary across different countries and service providers, highlighting the need to establish reliable benchmarks against which utilisation rates can be assessed. Here, optimal utilisation rates of Stereotactic Ablative Body Radiotherapy (SABR) for lung cancer are estimated and compared against actual utilisation rates to identify potential shortfalls in service provision.

Materials and Methods

An evidence-based optimal utilisation model was constructed after reviewing practice guidelines and identifying indications for lung SABR based on the best available evidence. The proportions of patients likely to develop each indication were obtained, whenever possible, from Australian population-based studies. Sensitivity analysis was performed to account for variations in epidemiological data. Practice pattern studies were reviewed to obtain actual utilisation rates.

Results

A total of 6% of all lung cancer patients were estimated to optimally require SABR at least once during the course of their illness (95% CI: 4–6%). Optimal utilisation rates were estimated to be 32% for stage I and 10% for stage II NSCLC. Actual utilisation rates for stage I NSCLC varied between 6 and 20%. For patients with inoperable stage I, 27–74% received SABR compared to the estimated optimal rate of 82%.

Conclusion

The estimated optimal SABR utilisation rates for lung cancer can serve as useful benchmarks to highlight gaps in service delivery and help plan for more adequate and efficient provision of care. The model can be easily modified to determine optimal utilisation rates in other populations or updated to reflect any changes in practice guidelines or epidemiological data.

M2 macrophage-derived exosomal long non-coding RNA AGAP2-AS1 enhances radiotherapy immunity in lung cancer by reducing microRNA-296 and elevating NOTCH2

Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) play vital roles in human diseases. We aimed to identify the effect of the lncRNA AGAP2 antisense RNA 1 (AGAP2-AS1)/miR-296/notch homolog protein 2 (NOTCH2) axis on the progression and radioresistance of lung cancer. Expression of AGAP2-AS1, miR-296, and NOTCH2 in lung cancer cells and tissues from radiosensitive and radioresistant patients was determined, and the predictive role of AGAP2-AS1 in the prognosis of patients was identified. THP-1 cells were induced and exosomes were extracted, and the lung cancer cells were respectively treated with silenced AGAP2-AS1, exosomes, and exosomes upregulating AGAP2-AS1 or downregulating miR-296. The cells were radiated under different doses, and the biological processes of cells were assessed. Moreover, the natural killing cell-mediated cytotoxicity on lung cancer cells was determined. The relationships between AGAP2-AS1 and miR-296, and between miR-296 and NOTCH2 were verified. AGAP2-AS1 and NOTCH2 increased while miR-296 decreased in radioresistant patients and lung cancer cells. The malignant behaviors of radioresistant cells were promoted compared with the parent cells. Inhibited AGAP2-AS1, macrophage-derived exosomes, and exosomes overexpressing AGAP2-AS1 or inhibiting miR-296 facilitated the malignant phenotypes of radioresistant lung cancer cells. Furthermore, AGAP2-AS1 negatively regulated miR-296, and NOTCH2 was targeted by miR-296. M2 macrophage-derived exosomal AGAP2-AS1 enhances radiotherapy immunity in lung cancer by reducing miR-296 and elevating NOTCH2. This study may be helpful for the investigation of radiotherapy of lung cancer.

The HNF1A-AS1/miR-92a-3p axis affects the radiosensitivity of non-small cell lung cancer by competitively regulating the JNK pathway

BACKGROUND

It has been widely reported that long non-coding RNAs (lncRNAs) could affect the varieties of tumor response to radiotherapy. LncRNA HNF1A-AS1 is transcribed from HNF1A gene cluster's antisense strand. This work focused on the mechanism of how HNF1A-AS1 participated in the radiosensitivity of non-small cell lung cancer (NSCLC).

METHODS

The mRNA or protein expression of HNF1A-AS1, miR-92a-3p MAP2K4, and JNK in NSCLC cells and tissues was detected by qRT-PCR or western blotting. RNA immunoprecipitation (RIP) detection and luciferase reporting system were used to evaluate the relationship between HNFA-AS1 and miR-92a-3p or between miR-92a-3p and MAP2K4. Flow cytometry assays, colony formation, and MTT were performed to analyze the function changes in A549 and Calu-1 cells. The rescue experiment was also conducted to explore the underlying mechanisms.

RESULTS

HNF1A-AS1 was investigated in NSCLC cells and tissues and highly related to the advanced pathological stage. HNF1A-AS1 bound with miR-92a-3p, which was downregulated in NSCLC. It showed that miR-92a-3p was negatively related to HNF1A-AS1. Knockdown of HNF1A-AS1 impacted most cell biological behaviors in NSCLC cells, including restricting the proliferation and aggravating apoptosis. Furthermore, knockdown of HNF1A-AS1 dramatically enhanced radiotherapy sensitivity of NSCLC. Moreover, miR-92a-3p was found to target MAP2K4 and could reduce MAP2K4 expression. Inhibition of HNF1A-AS1 elevated radiotherapy sensitivity and retarded the progression of NSCLC cells, followed by decreasing expression levels of MAP2K4. Besides, MAP2K4 mimic rescued the si-HNF1A-AS1 effects on the biological behavior of NSCLC cells.

CONCLUSION

HNF1A-AS1 is highly expressed in NSCLC. MiR-92a-3p is the target gene of HNF1A-AS1 and involved in tumor progression by regulating the MAP2K4/JNK pathway. HNF1AS1/miR-92a-3p/MAP2K4 axis plays important roles in radiotherapy resistance of NSCLC.

Factors affecting radiotherapy utilisation in geriatric oncology patients in NSW, Australia

Background and Purpose

Large non-age-specific radiotherapy utilisation rate (RTU) studies have demonstrated that actual RTU is below the optimal recommended utilisation rate for both curative and palliative intent radiotherapy indications. The optimal utilisation rate for the geriatric oncology cohort of patients has not yet been determined. The purpose of this research was to examine the actual RTU for patients treated in New South Wales (NSW), Australia as a function of increasing age, and the relationship between RTU and tumour site, travelling distance and socio-economic status.

Materials & Methods

NSW Central Cancer Registry data (2009-2011) were linked to the NSW Radiotherapy Dataset (2009-2012). RTU was calculated for patients aged <80 years and ≥80 years. RTU was defined as the proportion of patients receiving at least a single course of radiotherapy within 12 months of a cancer diagnosis.

Results

110,645 patients were diagnosed with cancer, of whom 27,721 received at least one course of radiotherapy. The overall RTU was 25%. RTU for patients aged <80 years was 28% compared to 14% for patients aged 80+ years (p < 0.001). On both univariate and multivariate analysis, increasing age, residential address in disadvantaged socioeconomic areas and increasing distance to the nearest radiotherapy department were associated with a reduction in RTU.

Conclusion

Geriatric oncology patients are less likely to receive radiotherapy than their younger counterparts. Some of the reduction in RTU may be justifiable on the basis of limited life expectancy and co-morbidity. Further research is required to determine the co-morbidity adjusted optimal RTU in older patients.

Radiotherapy treatment for lung cancer: Current status and future directions

Radiotherapy is an important modality used for the treatment of lung cancer. Seventy-seven percent of all patients with lung cancer have an evidence-based indication for radiotherapy, although it is often underutilized. Radiotherapy can be used as curative or palliative treatment across all stages of disease. Technological advances have allowed better radiotherapy targeting of tumours and reduced incidental irradiation of surrounding normal tissues. This has expanded the indications for radiotherapy in lung cancer and improved outcomes both in terms of increasing survival and reducing toxicity. This review examines the current role of radiotherapy in lung cancer, discusses the evidence behind this and identifies future directions in the radiotherapy treatment of lung cancer.

Co-Expression Network Analysis Identified Genes Associated with Cancer Stem Cell Characteristics in Lung Squamous Cell Carcinoma

Objective: Cancer stem cells are self-renewal cells in tumors and can produce heterogeneous tumor cells, which play an important role in the development of lung squamous cell carcinoma (LSCC). In our research, we aimed to explore the expression of genes related to LSCC stem cells.Methods: We downloaded the RNAseq data, the pathological and prognostic profiles of LSCC cases from the public database TCGA. The mRNA expression-based stiffness index (mRNAsi) of LSCC was calculated and the prognostic value of mRNAsi was discussed. Then, we constructed a weighted gene co-expression network analysis (WGCNA) to screen key genes related to mRNAsi of LSCC.Results: MRNAsi is an independent prognostic factor in LSCC. We screened 5 key genes (BUB1, BIRC5, CCNB2, KIF15 and SPAG5) related to mRNAsi of LSCC based on WGCNA. The key genes were highly expressed in the tumor samples compared to the normal samples. In addition, there is a strong interaction between proteins of these key genes and a strong co-expression relationship at the transcriptional level.Conclusions: To conclude, mRNAsi play an important role in LSCC. Five key genes (BUB1, BIRC5, CCNB2, KIF15 and SPAG5) related to mRNAsi were screened, which may act as therapeutic targets for inhibiting the stem cell characteristics of LSCC.

What is the optimal radiotherapy utilization rate for lung cancer?-a systematic review

Lung cancer is a major cause of morbidity and mortality globally. Although radiotherapy (RT) may be beneficial in the radical and/or palliative management of many lung cancer patients, it is underutilized worldwide. Population-level development of RT resources requires estimates of optimal radiotherapy utilization rates (ORUR) and actual radiotherapy utilization rate (ARUR). A systematic review of PubMed database for English-language articles from January 2009 to January 2019 was performed. Keywords included utilization, underutilization, demand, epidemiologic, benchmark, RT and cancer. Data abstracted included: study population, diagnosis, stage, year of diagnosis, timing of RT, intent of RT, ARUR, and ORUR. Eligible studies provided ARUR or ORUR for lung cancer, small cell lung cancer (SCLC), or non-small cell lung cancer (NSCLC). Included ARUR were based on at least 1,000 patients who were diagnosed or treated in 2009 or later. Included ORUR were based on evidence review or ARUR in 2009 or later. The initial search strategy yielded 1,627 unique abstracts. After review, 105 articles were determined appropriate for full-text review. From these, a final set of 21 articles met all inclusion criteria. In eight papers, ORUR was estimated. Estimated lifetime ORUR ranged from 61% to 82%. Methods for estimation included the evidence-based guideline model, Malthus model, and criterion-based benchmarking (CBB) model. The majority of estimates (6/8) used the evidence-based guideline model. Fifteen papers provided ARUR on lung cancer, inclusive of SCLC and NSCLC. ARUR within 9 months to 1 year of diagnosis ranged from 39% to 46%. Lifetime ARUR was an estimated 52% in Ontario, Canada. Palliative intent ARUR ranged from 12% in Central Poland to 46% in Ontario, Canada. RT is underutilized for lung cancer globally, and there is wide geographical variation in the level of underutilization.

Estimating the cost of radiotherapy for 5-year local control and overall survival benefit

BACKGROUND AND PURPOSE

Escalating health care costs have led to greater efforts directed at measuring the cost and benefits of medical treatments. The aim of this study was to estimate the costs of 5-year local control and overall survival benefits of radiotherapy for the cancer population in Australia.

MATERIALS AND METHODS

The local control and overall survival benefits of radiotherapy at 5-years and optimal number of fractions per course have been estimated for 26 tumour sites for which radiotherapy is indicated. For this study, a hybrid approach that merges features from activity based costing (ABC) and relative value units costing (RVU) were used to provide cost estimates. ABC methodology was used to allocate costs to all radiotherapy activities associated with each patient's treatment course, while the RVUs represent the cost of each radiotherapy activity relative to the average cost of all activities and were used to achieve a weighted cost allocation. A patient's journey for the financial year was constructed by consolidating all the radiotherapy activities and their associated costs, and the average cost per activity (fraction) was determined. The cost of radiotherapy per 5-year overall survival and local control was then estimated.

RESULTS

The estimated population 5-year local control and overall survival benefits of radiotherapy for all cancer were 23% and 6%, respectively. The optimal number of fractions per treatment course if guidelines were followed was 19.4 fractions. The average cost per fraction for all cancer was AU$276. The estimated cost of radiotherapy was AU$23,585 per 5-year local control and AU$86,480 per 5-year overall survival (equivalent to 5 life years) for all cancer.

CONCLUSION

The cost of AU$86,480 per 5-year overall survival would translate to AU$17,296 1-year overall survival. Therefore, the cost of radiotherapy is inexpensive if delivered optimally. Policy implications from this study include knowledge about cost to deliver radiotherapy to allow one to quantify the expected benefit at a population level.

Development of single nanometer-sized ultrafine oxygen bubbles to overcome the hypoxia-induced resistance to radiation therapy via the suppression of hypoxia-inducible factor‑1α

Radiation therapy can result in severe side-effects, including the development of radiation resistance. The aim of this study was to validate the use of oxygen nanobubble water to overcome resistance to radiation in cancer cell lines via the suppression of the hypoxia-inducible factor 1-α (HIF-1α) subunit. Oxygen nanobubble water was created using a newly developed method to produce nanobubbles in the single-nanometer range with the ΣPM-5 device. The size and concentration of the oxygen nanobubbles in the water was examined using a cryo-transmission electron microscope. The nanobubble size was ranged from 2 to 3 nm, and the concentration of the nanobubbles was calculated at 2×10¹⁸ particles/ml. Cell viability and HIF-1α levels were evaluated in EBC-1 lung cancer and MDA-MB-231 breast cancer cells treated with or without the nanobubble water and radiation under normoxic and hypoxic conditions in vitro. The cancer cells grown in oxygen nanobubble-containing media exhibited a clear suppression of hypoxia-induced HIF-1α expression compared to the cells grown in media made with distilled water. Under hypoxic conditions, the EBC-1 and MDA-MB231 cells displayed resistance to radiation compared to the cells cultured under normoxic cells. The use of oxygen nanobubble medium significantly suppressed the hypoxia-induced resistance to radiation compared to the use of normal medium at 2, 6, 10 and 14 Gy doses. Importantly, the use of nanobubble media did not affect the viability and radiation sensitivity of the cancer cell lines, or the non-cancerous cell line, BEAS-2B, under normoxic conditions. This newly created single-nanometer range oxygen nanobubble water, without any additives, may thus prove to be a promising agent which may be used to overcome the hypoxia-induced resistance of cancer cells to radiation via the suppression of HIF-1α.

The population benefit of evidence-based radiotherapy: 5-Year local control and overall survival benefits

BACKGROUND

To describe the population benefit of radiotherapy in a high-income setting if evidence-based guidelines were routinely followed.

METHODS

Australian decision tree models were utilized. Radiotherapy alone (RT) benefit was defined as the absolute proportional benefit of radiotherapy compared with no treatment for radical indications, and of radiotherapy over surgery alone for adjuvant indications. Chemoradiotherapy (CRT) benefit was the absolute incremental benefit of concurrent chemoradiotherapy over RT. Five-year local control (LC) and overall survival (OS) benefits were measured. Citation databases were systematically queried for benefit data. Meta-analysis and sensitivity analysis were performed.

FINDINGS

48% of all cancer patients have indications for radiotherapy, 34% curative and 14% palliative. RT provides 5-year LC benefit in 10.4% of all cancer patients (95% Confidence Interval 9.3, 11.8) and 5-year OS benefit in 2.4% (2.1, 2.7). CRT provides 5-year LC benefit in an additional 0.6% of all cancer patients (0.5, 0.6), and 5-year OS benefit for an additional 0.3% (0.2, 0.4). RT benefit was greatest for head and neck (LC 32%, OS 16%), and cervix (LC 33%, OS 18%). CRT LC benefit was greatest for rectum (6%) and OS for cervix (3%) and brain (3%). Sensitivity analysis confirmed a robust model.

INTERPRETATION

Radiotherapy provides significant 5-year LC and OS benefits as part of evidence-based cancer care. CRT provides modest additional benefits.

Prediction of Treatment Response for Combined Chemo- and Radiation Therapy for Non-Small Cell Lung Cancer Patients Using a Bio-Mathematical Model

The goal of this work was to develop a mathematical model to predict Kaplan-Meier survival curves for chemotherapy combined with radiation in Non-Small Cell Lung Cancer patients for use in clinical trial design. The Gompertz model was used to describe tumor growth, radiation effect was simulated by the linear-quadratic model with an α/β-ratio of 10, and chemotherapy effect was based on the log-cell kill model. To account for repopulation during treatment, we considered two independent methods: 1) kickoff-repopulation using exponential growth with a decreased volume doubling time, or 2) Gompertz-repopulation using the gradually accelerating growth rate with tumor shrinkage. The input parameters were independently estimated by fitting to the SEER database for untreated tumors, RTOG-8808 for radiation only, and RTOG-9410 for sequential chemo-radiation. Applying the model, the benefit from concurrent chemo-radiation comparing to sequential for stage III patients was predicted to be a 6.6% and 6.2% improvement in overall survival for 3 and 5-years respectively, comparing well to the 5.3% and 4.5% observed in RTOG-9410. In summary, a mathematical model was developed to model tumor growth over extended periods of time, and can be used for the optimization of combined chemo-radiation scheduling and sequencing.

Cancer Deaths due to Lack of Universal Access to Radiotherapy in the Brazilian Public Health System

AIMS

Radiotherapy plays a fundamental role in the treatment of cancer. Currently, the Brazilian public health system cannot match the national radiotherapy demand and many patients requiring radiotherapy are never exposed to this treatment. This study estimated the number of preventable deaths in the public health system if access to radiotherapy was universal.

MATERIALS AND METHODS

Incidence rates for the year 2016 provided by Instituto Nacional de Cancer were used in this analysis. The number of untreated patients requiring radiotherapy was obtained through the difference between the total number of patients requiring radiotherapy and the total amount of delivered radiotherapy treatments in the public health system. The number of deaths for the three most common cancers in each gender due to radiotherapy shortage was calculated. Initially, the total number of patients per cancer type was divided in stages using Brazilian epidemiological data. Subsequently, previously published tree arm diagrams were used to define the rate of patients requiring radiotherapy in each specific clinical setting. Finally, the clinical benefit of radiotherapy in overall survival was extracted from studies with level 1 evidence.

RESULTS

Over 596 000 cancer cases were expected in Brazil in 2016. The public health system covers more than 75% of the Brazilian population and an estimated 111 432 patients who required radiotherapy in 2016 did not receive this treatment. Breast, colorectal and cervix cancers are the most frequent malignant tumours in women and prostate, lung and colorectal in men. The number of deaths due to a radiotherapy shortage in the year 2016 for these types of cancer were: (i) breast: 1011 deaths in 10 years; (ii) cervix: 2006 deaths in 2 years; (iii) lung: 1206 deaths in 2 years; (iv) prostate, intermediate risk: 562 deaths in 13 years; high risk: 298 deaths in 10 years; (v) colorectal: 0 deaths, as radiotherapy has no proven benefit in overall survival.

CONCLUSION

Thousands of cancer patients requiring radiotherapy do not have access to this treatment in the Brazilian public health system. The shortage of radiotherapy has a significant detrimental effect on cancer survival; over 5000 deaths would probably be prevented in the most common cancer types if radiotherapy access was universal.