Biological effects of low-dose-rate irradiation of pancreatic carcinoma cells in vitro using 125I seeds

Computed tomography-guided radioactive iodine-125 seed implantation for liver malignancies in challenging locations

AIMS

This study aimed to retrospectively assess the safety and efficacy of radioactive iodine-125 (I-125) seed implantation for liver malignancies in challenging locations.

MATERIALS AND METHODS

Between December 2015 and December 2021, 49 patients with 60 liver malignancies in challenging locations who underwent computed tomography (CT)-guided I-125 seed implantation were retrospectively analyzed. The primary endpoints included technical success rate and overall survival (OS), whereas the secondary endpoints included progression-free survival (PFS), disease control rate (DCR), objective response rate (ORR), and liver recurrence. Potential factors associated with liver recurrence were also evaluated.

RESULTS

The technical success rate was 100%. The median follow-up duration was 12 months (range, 2-68 months). The mean OS and PFS were 17.58 months (95% CI: 13.64-21.52 months) and 13.14 months (95% CI: 10.36-15.92 months), respectively. The 2-month, 6-month, and 1-year DCR and ORR were 97.96% and 93.88%, 93.75% and 77.08%, and 93.48% and 60.87%, respectively. The 6- and 12-month tumor recurrence rates were 20.41% and 28.26%, respectively. The Kaplan-Meier method was used to estimate the time of liver recurrence, with our results showing that patients with primary intrahepatic cholangiocarcinoma had an increased likelihood of having earlier liver recurrence. No major complications developed during follow-up.

CONCLUSION

CT-guided radioactive I-125 implantation could be a safe and effective alternative with promising survival benefits and high local control rates for liver malignancies in challenging locations.

The efficacy of coaxial percutaneous iodine-125 seed implantation combined with arterial infusion chemotherapy for advanced pancreatic cancer: a randomized clinical trial

BACKGROUND

This study aimed to evaluate the clinical efficacy of coaxial percutaneous Iodine-125 (125I) seed implantation in combination with arterial infusion chemotherapy for the treatment of advanced pancreatic cancer (PC) through a randomized controlled trial.

METHODS

A total of 101 patients with advanced PC were randomized into two groups: control group treated with systemic intravenous chemotherapy and experimental group that received 125I seed implantation in combination with arterial infusion chemotherapy. Outcomes, including tumor control, abdominal pain relief, and survival time were compared between these two groups (Trial Registration No. KYKT2018-65).

RESULTS

Pretreatment abdominal pain scores were comparable between the two groups, whereas the abdominal pain scores at 1- and 3-month post-treatment were significantly lower in the control group than those in the experimental group (1-month: 3.74 ± 1.54 vs. 4.48 ± 1.46, p = .015; 3-month: 3.64 ± 2.21 vs. 5.40 ± 1.56, p < .001). At 3-month post-treatment, computed tomography (CT) scan revealed a significantly higher disease control rate in the experimental group than that in the control group (94.0% vs. 74.5%, p = .007). The median survival time in the experimental group was significantly longer than that in the control group (15-month vs. 9-month, p < .001).

CONCLUSION

The combination of coaxial percutaneous 125I seed implantation with arterial infusion chemotherapy could significantly alleviate abdominal pain, improve tumor control rates, and prolong survival time in patients with advanced PC.

Effects of iodine-125 seed brachytherapy on patients with heterochronous pulmonary metastasis from hepatocellular carcinoma: A propensity score matching study

Purpose

To investigate the effects of iodine-125 seed brachytherapy (ISB) on the overall survival (OS) of patients with heterochronous pulmonary metastasis (HPM) secondary to hepatocellular carcinoma (HCC).

Materials and Methods

The clinical and imaging data of 123 patients with HPM secondary to HCC treated at a single center from July 2012 to July 2020 were analyzed retrospectively. The patients were divided into ISB and non-ISB groups based on ISB treatment. Propensity score matching yielded 46 pairs of patients. A total of 191 lesions were treated, and the data were evaluated for 6 months after ISB. The OS rates of the two groups were compared using the Kaplan-Meier method. Independent prognostic factors were determined using a Cox proportional hazards regression model.

Results

The percentages of lung lesions in complete remission, partial remission, disease stable, and disease progression stages were 49.2%, 32.8%, 9.6%, and 8.4%, respectively. The disease control rate was 91.6%. The median follow-up time from the initial diagnosis was 47 months and 33 months for the ISB and non-ISB groups, respectively. Patients in the ISB group had a longer OS than those in the non-ISB group (1-year: 95.7% vs. 80.3%; 3-year: 62.9% vs. 45.7%; 5-year: 37% vs. 20.9%; P < 0.05). Multivariate analysis demonstrated that ISB treatment, tumor differentiation, vascular invasion, and Child - Pugh score were independent prognostic factors for survival.

Conclusion

ISB improves local control and OS rates of HPM secondary to HCC; thus, it is an effective and feasible option for patients with HPM secondary to HCC.

Tolerance limit of external beam radiotherapy combined with low-dose rate brachytherapy in normal rabbit tissue

BACKGROUND

Dosage-optimized multimodal radiotherapies that are safe for head and neck cancer patients are desirable. In this study, we investigated tissue tolerance to varying doses of external beam radiotherapy (EBRT) combined with low-dose rate brachytherapy in the neck of a rabbit model.

METHODS

Twenty rabbits were used in the four test groups (five each) with iodine-125 seeds implanted in the neck treated with EBRT in four doses at 50, 40, 30 and 20 Gy each. Twelve rabbits for three control groups (four each). Three months after implantation, all rabbits were euthanized, and target tissues were collected. Analyses included seed implantation assessment, histopathological evaluation, immunohistochemistry staining, terminal deoxynucleotidyl transferase dUTP nick end labeling assay, electron microscopy and statistics with the SPSS software.

RESULTS

Five rabbits died in the four test groups, and three rabbits died in the three control groups (one per group), which showed no significant difference by survival analysis. The calculated minimum peripheral dose was 17.6 Gy, the maximum dose near the seed was 1812.5 Gy, the D90 was 34.5 Gy and the mean dose was 124.5 Gy. In all groups that received radiation, apoptosis occurred primarily in the esophageal mucosa and corresponded to the dose of radiation; a higher dose caused a greater apoptosis, with significant difference between groups (P < 0.05). Electron microscopy of carotid arteries revealed that endothelial cells were swollen and some were shed from basement membrane, but no other noticeable tissue damages.

CONCLUSIONS

Limited EBRT at maximal dose (50 Gy) combined with the brachytherapy interstitially applied to the neck was tolerated well in the rabbit model.

Transarterial chemoembolisation plus I125 seeds implantation for people with unresectable hepatocellular carcinoma

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the benefits and harms of transarterial chemoembolisation (TACE) plus I125 seeds implantation compared with TACE alone, regardless of chemotherapeutic drugs and vascular occlusive agents, for people with unresectable hepatocellular carcinoma. 

Involvement of elevated ASF1B in the poor prognosis and tumorigenesis in pancreatic cancer

Anti-silencing function 1B (ASF1B) has been reported to be associated with the occurrence of many kinds of tumors. However, the biological effect and action mechanism of ASF1B in pancreatic cancer (PC) tumorigenesis remain unclear. The expression and prognosis value of ASF1B in PC were analyzed using GEPIA, GEO, and Kaplan-Meier plotter databases. The diagnostic value of ASF1B in PC was determined by receiver operating characteristic curve. The relationship between ASF1B expression and the clinical feathers in PC was investigated based on TCGA. qRT-PCR and western blot analyses were used to measure ASF1B expression in PC cells. Cell proliferation was evaluated by MTT and EdU assays, and apoptosis was examined by TUNEL and caspase-3 activity assays. Western blot analysis was utilized to detect the expression of proliferating cell nuclear antigen (PCNA), cyclin D1, Bax, Bcl-2, and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling proteins. ASF1B was overexpressed in several digestive cancers, including PC. Upregulated ASF1B was correlated with the poor prognosis and clinical features in PC patients. The area under the curve (AUC) value of ASF1B was 0.990. ASF1B was also overexpressed in PC cells. ASF1B silencing inhibited PC cell proliferation, promoted apoptosis, and increased caspase-3 activity, which were accompanied by the reduction of PCNA and cyclin D1 expression and increase of the ratio of Bax/Bcl-2 expression. Additionally, ASF1B silencing suppressed the PI3K/Akt pathway and 740Y-P treatment partially abolished the effects of ASF1B knockdown on PC cells. In conclusion, ASF1B silencing retarded proliferation and promoted apoptosis in PC cells by inactivation of the PI3K/Akt pathway.

Microdosimetric and radiobiological effects of gold nanoparticles at therapeutic radiation energies

PURPOSE

The purpose of this study was to quantify the microscopic dose distribution surrounding gold nanoparticles (GNPs) irradiated at therapeutic energies and to measure the changes in cell survival in vitro caused by this dose enhancement.

METHODS

The dose distributions from secondary electrons surrounding a single gold nanosphere and single gold nanocube of equal volume were both simulated using MCNP6. Dose enhancement factors (DEFs) in the 1 μm3 volume surrounding a GNP were calculated and compared between a nanosphere and nanocube and between 6 and 18 MV energies. This microscopic effect was explored further by experimentally measuring the cell survival of C-33a cervical cancer cells irradiated at 18 MV with varying doses of energy and concentrations of GNPs. Survival of cells receiving no irradiation, a 3 Gy dose, and a 6 Gy dose of 18 MV energy were determined for each concentration of GNPs.

RESULTS

It was observed that the dose from electrons surrounding the gold nanocube surpasses that of a gold nanosphere up to a distance of 1.1 μm by 18.5% for the 18 MV energy spectrum and by 23.1% for the 6 MV spectrum. DEFs ranging from ∼2 to 8 were found, with the maximum DEF resulting from the case of the gold nanocube irradiated at 6 MV energy. Experimentally, for irradiation at 18 MV, incubating cells with 6 nM (0.10% gold by mass) GNPs produces an average 6.7% decrease in cell survival, and incubating cells with 9 nM (0.15% gold by mass) GNPs produces an average 14.6% decrease in cell survival, as compared to cells incubated and irradiated without GNPs.

CONCLUSION

We have successfully demonstrated the potential radiation dose enhancing effects in vitro and microdosimetrically from gold nanoparticles.

Cytotoxicity of Metal-Based Nanoparticles: From Mechanisms and Methods of Evaluation to Pathological Manifestations

Metal-based nanoparticles (NPs) are particularly important tools in tissue engineering-, drug carrier-, interventional therapy-, and biobased technologies. However, their complex and varied migration and transformation pathways, as well as their continuous accumulation in closed biological systems, cause various unpredictable toxic effects that threaten human and ecosystem health. Considerable experimental and theoretical efforts have been made toward understanding these cytotoxic effects, though more research on metal-based NPs integrated with clinical medicine is required. This review summarizes the mechanisms and evaluation methods of cytotoxicity and provides an in-depth analysis of the typical effects generated in the nervous, immune, reproductive, and genetic systems. In addition, the challenges and opportunities are discussed to enhance future investigations on safer metal-based NPs for practical commercial adoption.

To explore the curative effect of CT-guided Iodine-125 radioactive seed implantation in the treatment of stage Ⅳprimary hepatocellular carcinoma

Objectives

To explore the clinical efficacy and survival of CT-guided Iodine-125 radioactive seed implantation in the treatment of stage Ⅳ primary hepatocellular carcinoma.

Methods

A retrospective study of 62 patients with primary hepatocellular carcinoma in our hospital from January 2017 to December 2018 [60 males, 2 females, age (52.76 ​± ​10.82) years old], All patients were implanted with Iodine-125 radioactive seeds under CT guidance, followed up regularly after operation to observe the clinical efficacy, including comparison of changes in cancer size before and after treatment, tumor marker AFP, and improvement in complications such as abdominal pain and ascites. Follow-up 3–36 months to assess patient survival.

Results

Among the 62 patients, 3 months after Iodine-125 radioactive seed implantation, 5 cases (8.1%) had complete remission of cancer, 33 cases (53.2%) had partial remission, 12 cases (19.4%) had stable lesions, and 12 cases (19.4%) had disease progression. The effective rate was 61.3%. The tumor volume (31.44 ​± ​14.51cm3) was significantly smaller than before (50.96 ​± ​30.13cm3) (t ​= ​5.303, p ​< ​0.05). The tumor marker AFP (69.28 ​± ​50.99) ug/L of 3 months after implantation was significantly lower than that before treatment (90.63 ​± ​68.58) ug/L (t ​= ​3.702, P ​< ​0.05). The average survival time of Iodine-125 seed implantation for stageⅣhepatocellular carcinoma is 11.47 ​± ​0.85 months, and the median survival time is 9 months. The survival time of the group with better pathological differentiation (gradeⅠ+Ⅱ) was significantly better than that of the group with poor differentiation (grade Ⅲ+Ⅳ) (x2 ​= ​6.869 p ​< ​0.05). Among the 38 patients with different degrees of abdominal pain, 22 patients improved better than before; 15 of 28 patients with different degrees of ascites were better than before. All patients had no serious complications related to treatment.

Conclusions

Iodine-125 radioactive seed implantation therapy can safely and effectively treat hepatocellular carcinoma, and relieve the clinical symptoms of abdominal pain and ascites.

Lentinan Combined with (125)I Brachytherapy for Recurrent Ovarian Cancer

Objective

To investigate the clinical value of lentinan combined with (125)I brachytherapy in the treatment of recurrent ovarian cancer.

Methods

A total of 160 patients with recurrent ovarian cancer admitted at Jiaozhou Central Hospital from June 2009 to October 2015 were enrolled in this study and randomly divided into observation group (80 cases) and control group (80 cases). The control group received chemotherapy. Observation group (80 cases) was treated with lentinan combined with (125)I brachytherapy on the basis of control group, and the efficacy, adverse reactions, and Karnofsky Performance Scale (KPS) and quality of life scale (QOL) scores of the two groups were analyzed and compared.

Results

After treatment, the levels of CA125, CA199, and CA724 in the 2 groups were markedly lower than those before treatment, and the observation group was lower than the control group (P < 0.05). After treatment, the proportion of CD4⁺/CD8⁺ cells and helper T cells and NK cells in the control group remarkably depleted, while the proportion of CD4⁺/CD8⁺ cells, NK cells, and B cells in the observation group increased significantly compared to that before treatment, and the level of IgA, IgG, and IgM in the control group decreased, while that in the observation group showed no conspicuous difference compared with that before chemotherapy (P > 0.05). The effective rate of observation group (85%) was higher than that of control group (75%) (P < 0.05). The overall survival of patients in the control group was (16.2 ± 2.04) months and that of the observation group was (24.8 ± 1.8) months. KPS and QOL scores in both groups were enormously higher than those before treatment, and the observation group was higher than the control group (P < 0.05). The incidence of hemoglobin reduction, leukopenia, aglobulia, granulocytopenia, nausea and vomiting, hepatorenal toxicity, and neurovirulence in the observation group was significantly lower than that in the control group.

Conclusion

Lentinan combined with (125)I brachytherapy is effective in treating recurrent ovarian cancer, with mild adverse reactions and good tolerance.

Eukaryotic Translation Initiation Factor 3 Subunit B Is a Promoter in the Development and Progression of Pancreatic Cancer

Background: Pancreatic cancer (PC) is a malignant tumor with hidden incidence, high degree of malignancy, rapid disease progression, and poor prognosis. Eukaryotic translation initiation factor 3 subunit B (EIF3B) is necessary for tumor growth, which is an alternative therapeutic target for many cancers. However, little is known about the relationship between EIF3B and PC.

Methods: The expression of EIF3B in PC was detected by immunohistochemistry. EIF3B knockdown cell models were constructed by lentivirus infection. The MTT assay, the wound-healing assay, the transwell assay, the flow cytometry, and the Human Apoptosis Antibody Array was used to detect the effects of EIF3B knockdown on cell proliferation, cell migration, cell apoptosis, and cell cycle in vitro. Also, the effects of EIF3B knockdown on the tumor growth of PC were determined in vivo.

Results: This study showed that the expression level of EIF3B was significantly up-regulated in PC tumor tissues and associated with pathological grade. In vitro, EIF3B knockdown inhibited the PC cell proliferation and migration, and the apoptosis levels were obviously promoted by regulating apoptosis-related proteins including Bcl-2, HSP27, HSP60, Survivin, sTNF-R2, TNF-α, TNF-β, TRAILR-3, TRAILR-4, and XIAP. Furthermore, the tumor growth of PC was inhibited after the knockdown of EIF3B in vivo.

Conclusion: EIF3B was up-regulated in PC and was a promoter in the development and progression of PC, which could be considered as a therapeutic target for the treatment of PC.

Palliative local treatment of bone metastases by 125I seed brachytherapy under DynaCT guidance: single-center experience

PURPOSE

We aimed to evaluate the clinical benefit of 125I seed brachytherapy under DynaCT guidance for palliative local treatment of bone metastases.

METHODS

From December 2014 to September 2017, 82 patients with painful bone metastases, who experienced treatment failure using standard strategies or rejected treatment were enrolled in this retrospective study. All patients underwent 125I seed brachytherapy under DynaCT guidance. Technical success, visual analogue scale (VAS), numerical rating scale (NRS), verbal rating scale (VRS), Karnofsky performance status (KPS) and complications were analyzed.

RESULTS

The success rate of 125I seed implantation was 100%. The VAS and NRS scores for the most severe pain were 7.0 (5.0-9.0) and 8.0 (6.0-9.0) before brachytherapy. The pain scores assessed every 2 hours gradually decreased within 12 hours (p < 0.001). A comparison of KPS scores showed that patients had significantly better quality of life on weeks 1, 4, and 8 than on week 0 (p < 0.001). The associated complications were mild subcutaneous hemorrhage 25.6% (21/82), fever 7.3% (6/82), minor displacement of radioactive seeds 5.0% (4/82), pathologic fracture 2.4% (2/82), and local skin reaction 2.4% (2/82). After symptomatic treatment, all complications were relieved. Minor displacement of radioactive seeds did not cause damage to adjacent tissues. No serious life-threatening complications occurred in the study group.

CONCLUSION

DynaCT-guided 125I seed implantation is a safe and effective method for palliation of painful bone metastases from cancer after failure or rejection of conventional treatments.

125I seeds irradiation inhibits tumor growth and induces apoptosis by Ki-67, P21, survivin, livin and caspase-9 expression in lung carcinoma xenografts

BACKGROUND

Lung cancer is a fatal disease and a serious health problem worldwide. Patients are usually diagnosed at an advanced stage, and the effectiveness of chemotherapy for such patients is very limited. Iodine 125 seed (¹²⁵I) irradiation can be used as an important adjuvant treatment for lung carcinoma. The purpose of this study was to examine the role of irradiation by 125I seeds in human lung cancer xenograft model and to determine the underlying mechanisms involved, with a focus on apoptosis.

METHODS

40 mice with A549 lung adenocarcinoma xenografts were randomly divided into 4 groups: control group (n = 10), sham seed (0 mCi) implant group (n = 10), 125I seed (0.6 mCi) implant group (n = 10) and 125I seed (0.8 mCi) implant group (n = 10), respectively. The body weight and tumor volume, were recorded every 4 days until the end of the study. Apoptotic cells were checked by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and activities of caspase-3 and caspase-8 enzyme were tested. Expression of P21, survivin, livin, caspase-9 and proliferating cell nuclear antigen (Ki-67) was detected with immunohistochemical staining.

RESULTS

The results of TUNEL staining assays showed that 125I seed irradiation suppresses the growth of lung cancer xenografts in nude mice and induced apoptosis. The activity of caspase-3 and caspase-8 was significantly higher. The expression levels Ki67, survivin and livin were substantially downregulated, while P21 and caspase-9 protein expression were significantly increased following 125I seed irradiation. This study revealed that 125I seed irradiation could significantly change apoptosis-related protein in human lung cancer xenografts.

CONCLUSIONS

Overall, our study demonstrates that radiation exposure by 125I seeds could be a new treatment option for lung cancer.

Iodine-125 seed implantation for residual hepatocellular carcinoma or cholangiocellular carcinoma in challenging locations after transcatheter arterial chemoembolization: Initial experience and findings

Purpose

To evaluate the clinical efficacy and safety of computed tomography (CT)-guided iodine-125 (¹²⁵I) seed implantation (ISI) for hepatocellular carcinoma (HCC) or cholangiocellular carcinoma (CCC) lesions in challenging locations after transcatheter arterial chemoembolization (TACE).

Material and methods

A retrospective single-center review of 24 patients with HCC or CCC tumors in challenging locations (hepatic dome or close to the heart/diaphragm/hepatic hilum) was conducted. Patients who underwent CT-guided ¹²⁵I implantation from May 2014 to January 2019 were recruited. Patients’ demographics and details including technical success, treatment response, patient survival, and complication rate were also evaluated.

Results

Treated tumors were located in the hepatic dome (n = 10; 41.7%), subcapsularly (n = 6; 25%), close to the heart (n = 3; 12.5%), and in the liver hilum (n = 5; 20.8%). The mean maximum diameter of tumors in challenging locations was 40.08 ±11.34 mm (range, 25-68 mm). TACE (2 ±1, 1-4 times) was applied before ISI. There were 27 ISI treatments administered (3 patients also received supplemental ISI). The total number of implanted seeds was 1,160, with mean 48 ±16 seed per patient (range, 30-90 seeds). The mean D₉₀ value for ISI was 125 Gy. Technical success rate was 100%, while a complete response + partial response (CR + PR) was documented in 70.83%, 79.17%, 83.33%, and 79.17% of patients at 3, 6, 12, and 24 months post-ISI, respectively. There were no major complications, although 2 cases experienced ¹²⁵I seed transfer to the diaphragm, and 1 case experienced transfer to the heart cavity.

Conclusions

CT-guided ISI for HCC or CCC lesions in challenging locations after TACE is both highly effective and safe.

Iodine‑125 seed radiation induces ROS‑mediated apoptosis, autophagy and paraptosis in human esophageal squamous cell carcinoma cells

Iodine-125 (¹²⁵I) seed brachytherapy has been proven to be a safe and effective treatment for advanced esophageal cancer; however, the mechanisms underlying its actions are not completely understood. In the present study, the anti-cancer mechanisms of ¹²⁵I seed radiation in human esophageal squamous cell carcinoma (ESCC) cells (Eca-109 and KYSE-150) were determined, with a particular focus on the mode of cell death. The results showed that ¹²⁵I seed radiation significantly inhibited cell proliferation, and induced DNA damage and G2/M cell cycle arrest in both ESCC cell lines. ¹²⁵I seed radiation induced cell death through both apoptosis and paraptosis. Eca-109 cells were primarily killed by inducing caspase-dependent apoptosis, with 6 Gy radiation resulting in the largest response. KYSE-150 cells were primarily killed by inducing paraptosis, which is characterized by extensive cytoplasmic vacuolation. ¹²⁵I seed radiation induced autophagic flux in both ESCC cell lines, and autophagy inhibition by 3-methyladenine enhanced radiosensitivity. Furthermore ¹²⁵I seed radiation induced increased production of reactive oxygen species (ROS) in both ESCC cell lines. Treatment with an ROS scavenger significantly attenuated the effects of ¹²⁵I seed radiation on endoplasmic reticulum stress, autophagy, apoptosis, paraptotic vacuoles and reduced cell viability. In vivo experiments showed that ¹²⁵I seed brachytherapy induced ROS generation, initiated cell apoptosis and potential paraptosis, and inhibited cell proliferation and tumor growth. In summary, the results demonstrate that in ESCC cells, ¹²⁵I seed radiation induces cell death through both apoptosis and paraptosis; and at the same time initiates protective autophagy. Additionally, ¹²⁵I seed radiation-induced apoptosis, paraptosis and autophagy was considerably mediated by ROS.

A review on the efficacy and safety of iodine-125 seed implantation in unresectable pancreatic cancers

Background: Pancreatic cancers are the common digestive system tumors with poor prognosis and due to its late diagnosis, surgical resection does not remain a viable treatment option in about 80% of patients. Amongst different treatment options, radioactive 125I seed implantation therapy has also emerged as a good alternative in non-resectable pancreatic cancer patients.Purpose: The present review describes the efficacy and safety of iodine-125 seed implantation in unresectable pancreatic cancers in preclinical and clinical studies.Results: In this technique, small radioactive particles are implanted inside the tumor cells to produce the sustain effects. Due to the short radial distance of these radiations, there is a selective and efficient killing of cancer cells without any significant injury to the neighboring cells. Amongst the different methods for implanting 125I seeds in the pancreatic tissues, CT scan or ultrasound-guided percutaneous seed implantation is preferred as it offers shorter operative time, lesser bleeding, early recovery, lesser complications, and low medical costs. The clinical studies have shown that radioactive 125I seed implantation is a good option for the management of local tumor growth, pain palliation, and improvement in the life span of patients suffering from unresectable pancreatic cancer.Conclusion: It may be employed either alone or in combination with cryotherapy, existing chemotherapy, bypass surgery or radiations to achieve the optimal results in these patients. Nevertheless, there is a need to formulate a uniform dose and procedure to achieve homogeneity and develop references for clinical practices.

Combined Effect of Moringa oleifera and Ionizing Radiation on Survival and Metastatic Activity of Pancreatic Cancer Cells

Background: Radiotherapy is one of the main treatments for malignancies. Radioresistance is a major obstacle in this treatment, calling for new treatments to improve radiotherapy outcome. Herbal medicine has low toxicity and could be a source for new radio-enhancing agents. Moringa oleifera (moringa) is a well-known medicinal plant with antiproliferative and antimetastatic properties. Possible mechanisms of moringa anticancer activity may be related to the expression of PARP-1, Bcl-2, COX-2, p65, p-IκB-a, and others. Purpose: The aims of the present study were to investigate effect of moringa alone and combined with radiation on survival and metastatic activity of pancreatic cancer cells and on tumor growth. Methods and Results: The combination of moringa and radiation significantly inhibited PANC-1 cell survival in a dose-dependent manner, as tested by clonogenic and XTT assays. Moreover, standard transwell cell migration/invasion assays demonstrated reduced metastatic activity of these cells. Pyruvate mitigated the inhibitory effect of combined treatment on cell survival. Flow cytometry of moringa-treated cells revealed induction of apoptosis. Western blot analysis found that the combined treatment decreased expression of the pro-apoptotic protein Bcl-2, and downregulated the key component of DNA repair pathways PARP-1 and the NF-κB-related proteins IκB-α, p65-subunit, and COX-2. Moringa significantly inhibited growth of subcutaneous tumors generated by PANC-1 cells in nude mice. Immunohistochemical analysis demonstrated moringa’s antiproliferative and antiangiogenic effects. Conclusions: Moringa decreased pancreatic cancer cell survival and metastatic activity and significantly inhibited tumor growth. The combination of moringa plus radiation resulted in an additional inhibitory effect that provided the rationale for further investigation of this combination as a novel strategy to overcome pancreatic cancer cell radioresistance.

The efficacy of 99mTc-MIBI imaging in 125I seed implantation treatment of rabbit VX2 transplanted liver cancer

PURPOSE

To evaluate the efficacy of ^99mTc-MIBI imaging in the evaluation of ¹²⁵I radioactive particle implantation for treatment of rabbit VX2 transplanted liver cancer.

METHODS

Twelve New Zealand white rabbit VX2 liver cancer models were successfully prepared by tumor cell suspension method and randomly divided into a control group and treatment group. The treatment group received ¹²⁵I particle implantation according to the TPS plan, and the control group received the same number of hollow particle implantation. ^99mTc-MIBI imaging was performed before and 7 d, 14 d, and 28 d after implantation. The target lesion (target, T) and normal liver tissue (nontarget, N) were determined by region of interest (ROI) technique. Radioactivity count was used to calculate the ^99mTc-MIBI uptake ratio (target-to-nontarget ratio, T/N) between the target lesion and normal liver tissue, thereby obtaining early ratio (ER) and delayed ratio (DR), respectively. The retention index (RI) was calculated. The mice were sacrificed after 28 days for histopathologic observation.

RESULTS

The T/N ratio, ER, and DR showed no statistical changes following the implantation time in the control group. In the treatment group, ER and DR gradually decreased after implantation of ¹²⁵I seeds (P < 0.05). There was no significant difference in RI during different observation times between the treatment group and the control group. Compared with the treatment group, RI exhibited no statistical difference between before and 7 d, 7~14 d, and 14~28 d after implantation (P > 0.05).

CONCLUSION

This method has value in evaluating the efficacy of ¹²⁵I seed implantation treatment of rabbit VX2 transplanted liver cancer. The T/N ratio is independent of the tumor diameter, but is related to the blood perfusion and metabolic state of the tumor. Implantation of ¹²⁵I particles into the rabbit transplanted liver cancer can effectively inhibit tumor growth, thus is a safe and effective method.

USP34 Regulated Human Pancreatic Cancer Cell Survival via AKT and PKC Pathways

Pancreatic cancer is known to be a fatal disease, which is difficult to be diagnosed in its early stages. Ubiquitin-Specific Protease 34 (USP34) are closely related to human cancers in the development and progression. However, there are rarely studies about the role of USP34 in pancreatic cancer. Thus, we aimed to investigate the effect of USP34 in human pancreatic cancer. Short-hairpin RNA targeting USP34 (USP34-shRNA) and USP34 overexpression lentivirus were used in the current study. The level of USP34 in human pancreatic cancer (PANC-1) cells were then analyzed by quantitative (q)RT-PCR. In addition, Western blotting was used to examine phosphorylated (p)-AKT, p-protein kinase C (PKC) and p-extracellular signal-regulated kinase (ERK) protein levels. CCK-8 assay, flow cytometry, and migration assay were used to detect cell proliferation, apoptosis and migration, respectively in vitro. According to the result of qRT-PCR and Western blotting, USP34-shRNA1 significantly downregulated USP34 gene level in PANC-1 cell. Subsequently, Western blotting assay indicated that USP34 silencing significantly down-regulated the expression of p-AKT and p-PKC in cells. On the other hand, USP34 overexpressing remarkably up-regulated the expression of p-AKT and p-PKC in cells. In addition, USP34 overexpression promoted PANC-1 cell proliferation and migration via up-regulating the proteins of p-AKT and p-PKC. Moreover, USP34 overexpression reversed AKT inhibitor and PKC inhibitor induced PACN-1 cell apoptosis. Our results indicated USP34 regulated h PANC-1 cell survival via AKT and PKC pathways, and which played a pro-survival role in human pancreatic cancer. Therefore, we suggested USP34 could be a potential therapeutic target for pancreatic cancer.

Evaluation of Iodine-125 Interstitial Brachytherapy Using Micro-Positron Emission Tomography/Computed Tomography with 18F-Fluorodeoxyglucose in Hepatocellular Carcinoma HepG2 Xenografts

BACKGROUND Iodine-125 interstitial brachytherapy (125I-IBT) is a promising treatment option for unresectable hepatocellular carcinoma (HCC). This study evaluated the usefulness of micro-positron emission tomography/computed tomography (micro-PET/CT) with 18F-fluorodeoxyglucose (18F-FDG) in assessing response to 125I-IBT in HCC HepG2 xenograft. MATERIAL AND METHODS Twelve mice with bilateral HepG2 xenografts were divided into 3 equal groups implanted with iodine-125 seeds into the left xenografts with a dose of 30, 50, and 80 Gy, respectively, and the right xenografts were used as internal controls. Before and 28 days after treatment, the 18F-FDG micro-PET/CT was performed. The ratios of left to right xenografts of tumor volume (RTV), maximum standardized uptake value (RSUVmax), mean optical density of caspase-3 expression (RMODcaspase-3), and apoptosis index (RAI) were compared. RESULTS The RTV means of the 50 and 80 Gy groups were significantly lower than in the 30 Gy group after treatment (P<0.01) and the RTV means after treatment were lower than baseline in the 50 and 80 Gy groups (P<0.05). The RSUVmax mean after treatment was lower than baseline in the 80 Gy group (P<0.05). The RMODCaspase-3 and RAI means of the 80 Gy group were higher than in the 30 Gy group (P<0.05). The RSUVmax was correlated negatively to RMODcaspase-3 (r=-0.624, P<0.05) and RAI (r=-0.651, P<0.05). CONCLUSIONS This study suggest that 125I-IBT inhibits tumor growth via upregulating caspase-3 expression and prompting apoptosis in HCC HepG2 xenografts. The 18F-FDG micro-PET/CT may be a useful functional imaging modality to assess early response to 125I-IBT in HCC HepG2 xenograft.

Preliminary application of 3D-printed coplanar template for iodine-125 seed implantation therapy in patients with advanced pancreatic cancer

AIM

To evaluate a 3D-printed coplanar template for iodine-125 seed implantation therapy in patients with pancreatic cancer.

METHODS

A retrospective analysis of our database was performed, and a total of 25 patients with pancreatic cancer who underwent iodine-125 seed implantation between January 2014 and November 2017 were analyzed. Of these, 12 implantations were assisted by a 3D-printed coplanar template (group A), and 13 implantations performed freehand were selected as a control group (group B). A 3D coplanar template was designed and printed according to a preoperative CT scan and treatment planning system. The iodine-125 seeds were then implanted using the template as a guide. Dosimetric verification was performed after implantation. Pre- and postoperative D90, V100, and V150 were calculated. The success rate of iodine-125 seed implantation, dosimetric parameters, and complications were analyzed and compared between the two groups.

RESULTS

Iodine-125 seed implantation was successfully performed in both groups. In group A, the median pre- and postoperative D90 values were 155.32 ± 8.05 Gy and 154.82 ± 16.43 Gy, respectively; the difference between these values was minimal and not statistically significant (P > 0.05). Postoperative V100 and V150 were 91.05% ± 4.06% and 64.54% ± 13.40%, respectively, which met the treatment requirement. A better dosimetric parameter was observed in group A than in group B, and the difference was statistically significant (V100: 91.05% ± 4.06% vs 72.91% ± 13.78%, P < 0.05). No major procedure-related complications were observed in either group. For group A, mild hemorrhage was observed in 1 patient with a peritoneal local hematoma due to mesenteric vein damage from the iodine-125 seed implantation needle. The hematoma resolved spontaneously without treatment. Postoperative blood amylase levels remained within the normal range for all patients.

CONCLUSION

A 3D-printed coplanar template appears to be a safe and effective iodine-125 seed implantation guidance tool to improve implantation accuracy and optimize dosimetric distribution.

Continuous Low-dose-rate Irradiation of Iodine-125 Seeds Inhibiting Perineural Invasion in Pancreatic Cancer

Background:

Perineural invasion (PNI) is a histopathological characteristic of pancreatic cancer (PanCa). The aim of this study was to observe the treatment effect of continuous low-dose-rate (CLDR) irradiation to PNI and assess the PNI-related pain relief caused by iodine-125 (¹²⁵I) seed implantation.

Methods:

The in vitro PNI model established by co-culture with dorsal root ganglion (DRG) and cancer cells was interfered under 2 and 4 Gy of ¹²⁵I seeds CLDR irradiation. The orthotopic models of PNI were established, and ¹²⁵I seeds were implanted in tumor. The PNI-related molecules were analyzed. In 30 patients with panCa, the pain relief was assessed using a visual analog scale (VAS). Pain intensity was measured before and 1 week, 2 weeks, and 1, 3, and 6 months after ¹²⁵I seed implantation.

Results:

The co-culture of DRG and PanCa cells could promote the growth of PanCa cells and DRG neurites. In co-culture groups, the increased number of DRG neurites and pancreatic cells in radiation group was significantly less. In orthotopic models, the PNI-positive rate in radiation and control group was 3/11 and 7/11; meanwhile, the degrees of PNI between radiation and control groups was significant difference (P < 0.05). At week 2, the mean VAS pain score in patients decreased by 50% and significantly improved than the score at baseline (P < 0.05). The pain scores were lower in all patients, and the pain-relieving effect was retained about 3 months.

Conclusions:

The CLDR irradiation could inhibit PNI of PanCa with the value of further study. The CLDR irradiation could do great favor in preventing local recurrence and alleviating pain.

Combination of 125I brachytherapy and chemotherapy for unresectable recurrent breast cancer: A retrospective control study

Recurrent breast cancer remains an incurable malignancy and cannot be removed by surgery in the majority of cases. This study aimed to explore the feasibility and efficacy of the combination of I brachytherapy and chemotherapy for the treatment of unresectable recurrent breast cancer. Patients with unresectable recurrent breast cancer treated between January 2011 and December 2014 with a combination of I brachytherapy and capecitabine or gemcitabine were evaluated and outcomes were compared with those of women treated with capecitabine or gemcitabine in conventional dose as a monotherapy. Of 61 patients evaluated, 28 received the combination treatment and 33 received capecitabine or gemcitabine monotherapy. The combination of I brachytherapy and chemotherapy resulted in a significant improvement in progression-free survival versus capecitabine or gemcitabine monotherapy (median, 17.8 vs 11.4 months; hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.23-0.84; P = 0.013). The objective response rate (ORR) was significantly higher with the combination (82.1%) than with monotherapy (54.5%; P = 0.022), and the rate of pain relief was higher in the combination arm (100% vs 73.6%; P = 0.038). There was no significant improvement for overall survival (median, 30.1 vs 27.2 months; HR, 0.82; 95% CI, 0.47-1.44; P = 0.496). There were no serious complications detected during the follow-up period, any grade toxicities were comparable between treatment arms. In conclusion, the combination of I brachytherapy and second-line chemotherapy is superior to chemotherapy alone and is an effective and safe therapy for unresectable recurrent breast cancer. However, further investigation and much larger scale randomized controlled trials with long-term follow-up are needed.

Numb/Notch signaling pathway modulation enhances human pancreatic cancer cell radiosensitivity

The present study aims to evaluate whether repression of the Numb/Notch signaling pathway affects the radiosensitivity of human pancreatic cancer cell lines. Different doses of X-rays (0, 2, 3, 4, and 5 Gy) were applied to the PANC-1, SW1990, and MIA PaCa-2 human pancreatic cancer cell lines, and the Numb/Notch pathway inhibitor DAPT was added at different doses (0, 1, 3, and 5 μmol/l). MTT assay, colony formation assay, flow cytometry, scratch assay, and Transwell experiments were performed, and qRT-PCR and Western blot were conducted for the detection of Numb expression. Tumorigenicity assay in nude mice was carried out to verify the influence of blocker of the Numb/Notch signaling pathway on the radiosensitivity of xenograft tumors. The MTT assay, colony formation assay and flow cytometry experiments revealed that proliferation decreased as radiation dose increased. The viability of PANC-1 cells at 5 Gy, SW 1990 cells at 4 Gy and 5 Gy, and MIA PaCa-2 cells at 2-5 Gy was significantly lower than that of non-irradiated cells (all P < 0.05). The migration and invasion assays indicated that the PANC-1 cell line was least radiosensitive, while the MIA PaCa-2 cell line was the most radiosensitive. Numb expression significantly increased with increasing radiation dose, whereas the expression of Hes1, Notch1, and Hes5 significantly decreased compared to non-irradiated cells (P < 0.05). Compared to untreated control cells, DAPT dose dependently increased Numb expression and inhibited Notch1, Hes1, and Hes5 expressions at 2 Gy (P < 0.05). Subcutaneous tumorigenicity assay in nude mice demonstrated that DAPT increased the radiosensitivity of PANC-1, SW 1990, and MIA PaCa-2 cells. These findings suggest that Numb/Notch signaling in pancreatic cancer cells is associated with X-ray radiation and that inhibition of the Numb/Notch signaling pathway can enhance radiosensitivity, suggesting that inhibition of the Numb/Notch signaling pathway may serve as a potential target for clinical improvement of the radiosensitivity of pancreatic cancer.

Clinical efficacy of computed tomography-guided iodine-125 seed implantation therapy in patients with advanced spinal metastatic tumors

Objective

The purpose of this study was to examine the safety and clinical efficacy of computed tomography (CT)-guided radioactive iodine-125 (¹²⁵I) seed implantation treatment in patients with spinal metastatic tumors.

Methods

We retrospectively analyzed 20 cases of spinal metastatic tumors, including nine men and eleven women aged 50–79 years (mean age: 61.1 years). We used treatment planning system (TPS) to construct three-dimensional images of the spinal metastatic tumors and to determine what number and dose rate distribution to use for the ¹²⁵I seeds. The matched peripheral dose of the ¹²⁵I seed implantation was 90–130 Gy. Twenty-four spinal metastatic tumors were treated by CT-guided radioactive ¹²⁵I seed implantation. A median of 19 (range: 4–43) ¹²⁵I seeds were implanted.

Results

Twenty cases were followed for a median of 15.3 months (range: 7–32 months). The rate of pain relief was 95%. The median control time for all of the patients was 12.5 months. The 3-, 6-, and 12-month cumulative local control rates were 100%, 95%, and 60%, respectively. The median survival time for all of the patients was 16 months. The cumulative 6- and 12-month survival rates were 100% and 78.81%, respectively. No major complications were observed. No ¹²⁵I seeds were lost or migrated to other tissues or organs.

Conclusion

CT-guided radioactive ¹²⁵I seed implantation is a safe, effective, and minimally invasive method for the treatment of patients with spinal metastatic tumors. It is a possible alternative therapy for the treatment of spinal metastases.