The Effects of Apigenin on Cell Proliferation and Apoptosis in Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is a WHO grade IV brain tumor. These tumors are highly proliferative, infiltrative, necrotic, angiogenic, and resistant to apoptosis. One major characteristic of GBM is the overexpression of epidermal growth factor receptor (EGFR), which leads to cell growth and proliferation when activated. GBM is very difficult to treat due to its location, heterogeneity, and invasiveness; an effective treatment is therefore needed. The use of flavonoids, which are natural compounds found in many fruits and vegetables, has been studied in the treatment of many different tumor types. Apigenin is a specific flavonoid that has previously been shown to have antitumor activity in a number of cancer cells. Our study set out to investigate the molecular effects of apigenin treatment on glioblastoma cell proliferation and viability using the trypan blue exclusion assay, MTT assay, and an LDH assay. In addition, Western blot analyses were utilized out to determine the signaling pathways through which apigenin treatment exerts its effects on cell proliferation and apoptosis. Finally, hoechst-propidium iodide staining and flow cytometry were used to examine the extent of apoptosis and the cell cycle context of these effects. Our results show that apigenin reduces cell viability and proliferation in a dose and time dependent manner while increasing cytotoxicity in GBM cells. Additionally, apigenin inhibits the EGFR mediated phosphorylation in the presence of EGF treatment of AKT, mTOR, and s6k resulting in decreased cell survival, growth and proliferation. It also inhibits the MAPK pathways in one cell line thereby reducing cell growth and proliferation. It also inhibits the anti-apoptotic effects of BCL-XL and increases PARP cleavage, which leads to increased apoptosis. Finally, apigenin induced cycle arrest at the G2M checkpoint, meaning that apoptosis primarily occurred at the DNA repair checkpoint in the cell cycle. In conclusion, apigenin has demonstrated some in vitro biological effects on glioblastoma cell lines that show promises in limiting the growth, proliferation and survival of these cell lines. Future research should look to identify means through which apigenin can be administered in clinically significant concentrations to the brain

Natural Products as Therapeutic Agents in Cancer Treatment

Cancer accounts for 25% of deaths in the United States, and brain tumors greatly contribute to this percentage. However, relative to other types of cancers, brain tumors prove difficult to treat because they are heterogeneous, highly proliferative, highly invasive, and resistant to the traditional cancer treatments of chemotherapy and radiotherapy. Past studies have shown that flavonoids and curcuminoids, two classes of compounds derived from natural sources, are effective in inhibiting the development and metastasis of breast and lung cancer cells. Research has also indicated that these compounds have potential for treating brain tumors. The purpose of this research is to further explore the potential of flavonoids as therapeutic options for the treatment of brain tumors. Specifically, flavonoids’ effect on cell proliferation, cell death, and tumor invasion will be studied. Another objective of this study is to identify the signaling mechanism by which flavonoids mediate their therapeutic effects on brain tumor cell lines. Three human brain tumor cell lines (U-1242, U-251, and U-87) will be studied. They will be treated with various flavonoids at increasing concentrations (10, 20, 40, and 80 µM). Cells will be counted following the trypan blue staining protocol. MTT assays and Western blot analyses will be used to assess cell proliferation. Cell death will be assessed with flow analyses and Western blot analyses. Unpaired t-tests will be run to compare treated and control cells at a 95% confidence interval. If necessary, one-way ANOVA with multiple comparisons will be used to compare multiple treatment groups and a control at a 95% confidence interval, and the Tukey post-hoc test will be utilized if appropriate. All statistical tests will be run in IBM SPSS 21®

Natural Products as Therapeutic Agents in Cancer Treatment

Cancer accounts for 25% of deaths in the United States, and brain tumors greatly contribute to this percentage. However, relative to other types of cancers, brain tumors prove difficult to treat because they are heterogeneous, highly proliferative, highly invasive, and resistant to the traditional cancer treatments of chemotherapy and radiotherapy. Past studies have shown that flavonoids and curcuminoids, two classes of compounds derived from natural sources, are effective in inhibiting the development and metastasis of breast and lung cancer cells. Research has also indicated that these compounds have potential for treating brain tumors. The purpose of this research is to further explore the potential of flavonoids as therapeutic options for the treatment of brain tumors. Specifically, flavonoids’ effect on cell proliferation, cell death, and tumor invasion will be studied. Another objective of this study is to identify the signaling mechanism by which flavonoids mediate their therapeutic effects on brain tumor cell lines. Three human brain tumor cell lines (U-1242, U-251, and U-87) will be studied. They will be treated with various flavonoids at increasing concentrations (10, 20, 40, and 80 µM). Cells will be counted following the trypan blue staining protocol. MTT assays and Western blot analyses will be used to assess cell proliferation. Cell death will be assessed with flow analyses and Western blot analyses. Unpaired t-tests will be run to compare treated and control cells at a 95% confidence interval. If necessary, one-way ANOVA with multiple comparisons will be used to compare multiple treatment groups and a control at a 95% confidence interval, and the Tukey post-hoc test will be utilized if appropriate. All statistical tests will be run in IBM SPSS 21®

The first reported case of a patient with pancreatic cancer treated with cone beam computed tomography-guided stereotactic adaptive radiotherapy (CT-STAR)

BACKGROUND: Online adaptive stereotactic radiotherapy allows for improved target and organ at risk (OAR) delineation and inter-fraction motion management via daily adaptive planning. The use of adaptive SBRT for the treatment of pancreatic cancer (performed until now using only MRI or CT on rails-guided adaptive radiotherapy), has yielded promising outcomes. Herein we describe the first reported case of cone beam CT-guided stereotactic adaptive radiotherapy (CT-STAR) for the treatment of pancreatic cancer. CASE PRESENTATION: A 61-year-old female with metastatic pancreatic cancer presented for durable palliation of a symptomatic primary pancreatic mass. She was prescribed 35 Gy/5 fractions utilizing CT-STAR. The patient was simulated utilizing an end-exhale CT with intravenous and oral bowel contrast. Both initial as well as daily adapted plans were created adhering to a strict isotoxicity approach in which coverage was sacrificed to meet critical luminal gastrointestinal OAR hard constraints. Kilovoltage cone beam CTs were acquired on each day of treatment and the radiation oncologist edited OAR contours to reflect the patient\u27s anatomy-of-the-day. The initial and adapted plan were compared using dose volume histogram objectives, and the superior plan was delivered. Use of the initial treatment plan would have resulted in nine critical OAR hard constraint violations. The adapted plans achieved hard constraints in all five fractions for all four critical luminal gastrointestinal structures. CONCLUSIONS: We report the successful treatment of a patient with pancreatic cancer treated with CT-STAR. Prior to this treatment, the delivery of ablative adaptive radiotherapy for pancreatic cancer was limited to clinics with MR-guided and CT-on-rails adaptive SBRT technology and workflows. CT-STAR is a promising modality with which to deliver stereotactic adaptive radiotherapy for pancreatic cancer

Alcohol Consumption is associated with Increased CEA Levels in Male Patients with Stage IV Colorectal Cancer- A Single-Institution Retrospective Analysis

Introduction: Alcohol use is an independent risk factor for liver metastasis, a major cause of morbidity and mortality in colorectal cancer (CRC) patients. Serum CEA level is an established prognostic indicator in CRC, yet the correlation with behavioral factors such as alcohol use remains to be defined. In a single-center review, we evaluated alcohol use, gender, and CEA levels in predicting advanced disease in CRC patients. Methods: Retrospective analysis of UNMC patients diagnosed with CRC as the primary cancer between 2012-2019, stages I-IV, and age \u3e19 with documentation of alcohol use. Univariable statistics were performed using Chi-Square and non-parametric tests. Associations between stage, gender, and alcohol use (some vs. none) and the log-transformed CEA outcome (either initial or rate of change) were assessed using linear regressions. Results: Alcohol use was found to be reported in 333 of 1243 CRC patients. The cohort was comprised of 192 male and 141 female subjects. Elevated CEA levels at CRC diagnosis were associated with increased all-cause mortality (33.0% for CEA \u3e 3.4ng/ml vs 10.4% for CEA \u3c 3.4ng/ml). Model analysis found that stage IV male alcohol users showed an increase in serial CEA levels compared to males who did not use alcohol, but this pattern was not observed among stage IV females. Conclusions: Males with a history of alcohol use may be at risk for advanced CRC disease suggesting the utility of serial serum CEA monitoring in these patients. A detailed alcohol use history should be obtained in all patients with CRC as it has prognostic value and may allow for early intervention. This analysis was limited by missing alcohol use data for the majority (73.2%) of CRC patients evaluated. A prospective study is warranted to define the implications of alcohol use and risk of CRC liver metastasis

The Antiproliferative and Apoptotic Effects of Apigenin on Glioblastoma Cells

OBJECTIVES: Glioblastoma (GBM) is highly proliferative, infiltrative, malignant and the most deadly form of brain tumour. The epidermal growth factor receptor (EGFR) is overexpressed, amplified and mutated in GBM and has been shown to play key and important roles in the proliferation, growth and survival of this tumour. The goal of our study was to investigate the antiproliferative, apoptotic and molecular effects of apigenin in GBM. METHODS: Proliferation and viability tests were carried out using the trypan blue exclusion, MTT and lactate dehydrogenase (LDH) assays. Flow cytometry was used to examine the effects of apigenin on the cell cycle check-points. In addition, we determined the effects of apigenin on EGFR-mediated signalling pathways by Western blot analyses. KEY FINDINGS: Our results showed that apigenin reduced cell viability and proliferation in a dose- and time-dependent manner while increasing cytotoxicity in GBM cells. Treatment with apigenin-induced is poly ADP-ribose polymerase (PARP) cleavage and caused cell cycle arrest at the G2M checkpoint. Furthermore, our data revealed that apigenin inhibited EGFR-mediated phosphorylation of mitogen-activated protein kinase (MAPK), AKT and mammalian target of rapamycin (mTOR) signalling pathways and attenuated the expression of Bcl-xL. CONCLUSION: Our results demonstrated that apigenin has potent inhibitory effects on pathways involved in GBM proliferation and survival and could potentially be used as a therapeutic agent for GBM

Feasibility of surface-guidance combined with CBCT for intra-fractional breath-hold motion management during Ethos RT

PURPOSE: High-quality CBCT and AI-enhanced adaptive planning techniques allow CBCT-guided stereotactic adaptive radiotherapy (CT-STAR) to account for inter-fractional anatomic changes. Studies of intra-fractional respiratory motion management with a surface imaging solution for CT-STAR have not been fully conducted. We investigated intra-fractional motion management in breath-hold Ethos-based CT-STAR and CT-SBRT (stereotactic body non-adaptive radiotherapy) using optical surface imaging combined with onboard CBCTs. METHODS: Ten cancer patients with mobile lower lung or upper abdominal malignancies participated in an IRB-approved clinical trial (Phase I) of optical surface image-guided Ethos CT-STAR/SBRT. In the clinical trial, a pre-configured gating window (± 2 mm in AP direction) on optical surface imaging was used for manually triggering intra-fractional CBCT acquisition and treatment beam irradiation during breath-hold (seven patients for the end of exhalation and three patients for the end of inhalation). Two inter-fractional CBCTs at the ends of exhalation and inhalation in each fraction were acquired to verify the primary direction and range of the tumor/imaging-surrogate (donut-shaped fiducial) motion. Intra-fractional CBCTs were used to quantify the residual motion of the tumor/imaging-surrogate within the pre-configured breath-hold window in the AP direction. Fifty fractions of Ethos RT were delivered under surface image-guidance: Thirty-two fractions with CT-STAR (adaptive RT) and 18 fractions with CT-SBRT (non-adaptive RT). The residual motion of the tumor was quantified by determining variations in the tumor centroid position. The dosimetric impact on target coverage was calculated based on the residual motion. RESULTS: We used 46 fractions for the analysis of intra-fractional residual motion and 43 fractions for the inter-fractional motion analysis due to study constraints. Using the image registration method, 43 pairs of inter-fractional CBCTs and 100 intra-fractional CBCTs attached to dose maps were analyzed. In the motion range study (image registration) from the inter-fractional CBCTs, the primary motion (mean ± std) was 16.6 ± 9.2 mm in the SI direction (magnitude: 26.4 ± 11.3 mm) for the tumors and 15.5 ± 7.3 mm in the AP direction (magnitude: 20.4 ± 7.0 mm) for the imaging-surrogate, respectively. The residual motion of the tumor (image registration) from intra-fractional breath-hold CBCTs was 2.2 ± 2.0 mm for SI, 1.4 ± 1.4 mm for RL, and 1.3 ± 1.3 mm for AP directions (magnitude: 3.5 ± 2.1 mm). The ratio of the actual dose coverage to 99%, 90%, and 50% of the target volume decreased by 0.95 ± 0.11, 0.96 ± 0.10, 0.99 ± 0.05, respectively. The mean percentage of the target volume covered by the prescribed dose decreased by 2.8 ± 4.4%. CONCLUSION: We demonstrated the intra-fractional motion-managed treatment strategy in breath-hold Ethos CT-STAR/SBRT using optical surface imaging and CBCT. While the controlled residual tumor motion measured at 3.5 mm exceeded the predetermined setup value of 2 mm, it is important to note that this motion still fell within the clinically acceptable range defined by the PTV margin of 5 mm. Nonetheless, additional caution is needed with intra-fractional motion management in breath-hold Ethos CT-STAR/SBRT using optical surface imaging and CBCT

Techno-Economic Feasibility Analysis of a Fully Mobile Radiation Oncology System using Monte Carlo Simulation

PURPOSEDisparities in radiation oncology (RO) can be attributed to geographic location, socioeconomic status, race, sex, and other societal factors. One potential solution is to implement a fully mobile (FM) RO system to bring radiotherapy to rural areas and reduce barriers to access. We use Monte Carlo simulation to quantify techno-economic feasibility with uncertainty, using two rural Missouri scenarios.METHODSRecently, a semimobile RO system has been developed by building an o-ring linear accelerator (linac) into a mobile coach that is used for temporary care, months at a time. Transitioning to a more FM-RO system, which changes location within a given day, presents technical challenges including logistics and quality assurance. This simulation includes cancer census in both northern and southeastern Missouri, multiple treatment locations within a given day, and associated expenditures and revenues. A subset of patients with lung, breast, and rectal diseases, treated with five fractions, was simulated in the FM-RO system.RESULTSThe FM-RO can perform all necessary quality assurance tests as suggested in national medical physics guidelines within 1.5 hours, thus demonstrating technological feasibility. In northern and southeastern Missouri, five-fraction simulations\u27 net incomes were, in US dollars (USD), $1.55 ± 0.17 million (approximately 74 patients/year) and$3.65 USD ± 0.25 million (approximately 98 patients/year), respectively. The number of patients seen had the highest correlation with net income as well as the ability to break-even within the simulation. The model does not account for disruptions in care or other commonly used treatment paradigms, which may lead to differences in estimated economic return. Overall, the mobile system achieved a net benefit, even for the most negative simulation scenarios.CONCLUSIONOur simulations suggest technologic success and economic viability for a FM-RO system within rural Missouri and present an interesting solution to address other geographic disparities in access to radiotherapy

A feasibility trial of skin surface motion-gated stereotactic body radiotherapy for treatment of upper abdominal or lower thoracic targets using a novel O-ring gantry

BACKGROUND AND PURPOSE: A novel O-ring gantry can deliver stereotactic body radiation therapy (SBRT) with artificial intelligence-facilitated, CT-guided online plan adaptation. It gates mobile targets by optically monitoring skin surface motion. However, this gating solution has not been clinically validated. We conducted a trial to evaluate the feasibility of optical skin surface-guided gating for patients with mobile upper abdominal or lower thoracic malignancies treated with SBRT on this platform (NCT05030454). MATERIALS AND METHODS: Ten patients who were prescribed SBRT to a thoracic or abdominal target and were capable of breath-hold for at least 17 s enrolled. They received SBRT in five fractions with breath-hold technique and optical skin surface motion monitored-gating with a ± 2 mm tolerance. Online plan adaptation was left to the discretion of the daily treating physician. The primary endpoint was defined as successful completion of \u3e 75 % of attempted fractions. Exploratory endpoints included local control and acute grade ≥ 3 toxicity rates after three months. For adapted fractions the contouring, planning, quality assurance, and treatment delivery times were recorded. RESULTS: Forty-seven of 51 SBRT fractions (92 %) were successfully gated at breath-hold by optical skin surface motion monitoring. The tumor centroid position during breath-hold varied by a mean of approximately 2 mm. Sixty-three percent of fractions were adapted online with a median total treatment time of 78.5 min. After three months no local recurrences or acute grade ≥ 3 toxicities were observed. CONCLUSIONS: SBRT treatment to mobile targets with surface-monitored gating on a novel O-ring gantry was prospectively validated