Comparing breath hold versus free breathing irradiation for left-sided breast radiotherapy by PlanIQ™.

BACKGROUND: Breast cancer is the most widespread cancer in women and young women worldwide. Moving towards customised radiotherapy, balancing the use of the available technology with the best treatment modality may not be an easy task in the daily routine. This study aims to evaluate the effectiveness of introducing IQ-feasibility into clinical practice to support the decision of free-breathing (FB) versus breath-hold (BH) left-sided breast irradiations, in order to optimise the technology available and the effectiveness of the treatment. METHODS: Thirty-five patients who received 3D radiotherapy treatment of the left breast in deep-inspiration BH were included in this retrospective study. Computed tomography scans in FB and BH were acquired for each patient; targets contoured in both imaging datasets by an experienced radiation oncologist, and organs at risk delineated using automatic segmentation software were exported to PlanIQ™ (Sun Nuclear Corp.) to generate feasibility dose volume histogram (FDVHs). The dosimetric parameter of BH versus FB FDVH, and BH clinical dataset versus BH FDVH were compared. RESULTS: A total of 30 patients out of 35 patients analysed, presented for the BH treatments a significant reduction (p < 0.05) in the heart mean dose ([Formula: see text]), volume receiving 5 Gy ([Formula: see text]) and 20 Gy ([Formula: see text]), of 35.7%, 54.5%, and 2.1%, respectively; for the left lung, a lower reduction was registered and significant only for [Formula: see text] (21.4%, p = 0.046). For the remaining five patients, the FDVH cut-off points of heart and lung were superimposable with differences of less than 1%. Heart and left lung dosimetric parameters of the BH clinical plans are located in the difficult zone of the FDVH and differ significantly (p < 0.05) from the corresponding parameters of the FDVH curves delimiting this buffer area between the impossible and feasible zones, respectively. CONCLUSION: The use of PlanIQTM as a decision-support tool for the FB versus BH treatment delivery modality allows customisation of the treatment technique using the most appropriate technology for each patient enabling accurate management of available technologies.

Correlation between AI-based CT organ features and normal lung dose in adjuvant radiotherapy following breast-conserving surgery: a multicenter prospective study.

BACKGROUND: Radiation pneumonitis (RP) is one of the common side effects after adjuvant radiotherapy in breast cancer. Irradiation dose to normal lung was related to RP. We aimed to propose an organ features based on deep learning (DL) model and to evaluate the correlation between normal lung dose and organ features. METHODS: Patients with pathology-confirmed invasive breast cancer treated with adjuvant radiotherapy following breast-conserving surgery in four centers were included. From 2019 to 2020, a total of 230 patients from four nationwide centers in China were screened, of whom 208 were enrolled for DL modeling, and 22 patients from another three centers formed the external testing cohort. The subset of the internal testing cohort (n = 42) formed the internal correlation testing cohort for correlation analysis. The outline of the ipsilateral breast was marked with a lead wire before the scanning. Then, a DL model based on the High-Resolution Net was developed to detect the lead wire marker in each slice of the CT images automatically, and an in-house model was applied to segment the ipsilateral lung region. The mean and standard deviation of the distance error, the average precision, and average recall were used to measure the performance of the lead wire marker detection model. Based on these DL model results, we proposed an organ feature, and the Pearson correlation coefficient was calculated between the proposed organ feature and ipsilateral lung volume receiving 20 Gray (Gy) or more (V20). RESULTS: For the lead wire marker detection model, the mean and standard deviation of the distance error, AP (5 mm) and AR (5 mm) reached 3.415 ± 4.529, 0.860, 0.883, and 4.189 ± 8.390, 0.848, 0.830 in the internal testing cohort and external testing cohort, respectively. The proposed organ feature calculated from the detected marker correlated with ipsilateral lung V20 (Pearson correlation coefficient, 0.542 with p < 0.001 in the internal correlation testing cohort and 0.554 with p = 0.008 in the external testing cohort). CONCLUSIONS: The proposed artificial Intelligence-based CT organ feature was correlated with normal lung dose in adjuvant radiotherapy following breast-conserving surgery in patients with invasive breast cancer. TRIAL REGISTRATION: NCT05609058 (08/11/2022).

Quality Evaluation of Volatile Oil in Yanyangke Mixture (YM) Based on GC-MS Fingerprint, GC Multicomponent Quantitative Analysis and Chemical Pattern Recognition Analysis.

Yanyangke mixture (YM) is composed of 12 kinds of traditional Chinese medicine (TCM) used for the treatment of patients with cough, dry throat and other diseases caused by acute or chronic pharyngitis or patients with difficulty in expectoration. With the wide application of YM in clinical practice, its quality control has attracted huge attention. Based on the multi-component characteristics of Chinese herbal medicines, it is pertinent to establish a quality evaluation system. A new idea is to adopt gas chromatography-mass spectrometry (GC-MS) chemical composition identification, GC-MS fingerprint, and GC content determination as a potential quality control index of the volatile oil in YM. In this study, the volatile oil of YM was extracted by steam distillation, and the chemical components of the volatile oil were analyzed by GC-MS, and 43 chemical components were identified. The fingerprint of the volatile oil from YM was established and the similarity evaluation was performed. Combined with chemometric methods, such as cluster analysis, principal component analysis and partial least squares analysis, the chemical composition differences of the volatile oil from different batches of YM were compared and the symbolic components affecting the quality of the volatile oil from different batches of YM were excavated. Finally, three components were selected as the potential active component markers of YM and the GC content determination method of these three components was established. A rapid, reasonable, and effective quality evaluation and control method of YM volatile oil was established, which provided a reference for further development and research on YM, as well as a new idea for research on other TCM prescriptions.

Construction of a novel immune-related prognostic-predicting model of gastric cancer.

Gastric cancer (GC) is a common primary stomach tumor of the central nervous system with a poor prognosis. In this study, 274 differentially expressed immune-related genes (DEIRGs) were identified among six cell subpopulations in GSE112302 single-cell RNA sequencing (scRNA-seq) data of GC. Those DEIRGs were able to divide GC patients into three distinct subtypes with different overall survivals and tumor microenvironment. By univariate Cox and LASSO regression analyses, eight immune-related genes, including CTGF, CXCL3, CXCR4, NRP1, OAS1, SP1, STC1 and TAP1, were identified as GC prognostic signatures. Accordingly, a risk score model for predicting GC prognosis was constructed in TCGA-GC training cohort and validated in the external GSE66229 dataset. Moreover, a nomogram for predicting the survival of GC patients was also established based on independent prognostic factors (age, grade, cancer status and risk score) identified by univariate and multivariate Cox regression analyses. In addition, Gene Set Variation Analysis (GSVA) analysis indicated that the prognostic immune signatures may regulate GC via inflammation and cell proliferation related pathways, such as DNA replication, complement and coagulation cascades, focal adhesion and TGF-ß signaling pathway.

A σE-mediated temperature gauge orchestrates type VI secretion system, biofilm formation and cell invasion in pathogen Pseudomonas plecoglossicida.

Pseudomonas plecoglossicida is a temperature-dependent opportunistic pathogen mediating visceral granulomas in many piscine species including the large yellow croaker (Larimichthys crocea) but the underlying mechanisms are unclear. RpoE is an alternative sigma (σ) factor involved in regulated intramembrane proteolytic (RIP) cascade, enabling bacterial pathogens to coordinate the expression of genetic traits associated with stress adaptation and virulence determinants in response to diverse stimuli in vitro and in vivo of the hosts. In this study, genes associated to RIP cascade in P. plecoglossicida were identified and characterized to show various sequence similarities to their counterparts in Escherichia coli and P. aeruginosa. The expression of P. plecoglossicida RIP locus was induced by higher temperatures. Moreover, RNA sequencing approach revealed that RpoE regulated the expression of ∼297 and ∼261 genes at virulent (18 °C) and non-virulent (28 °C) temperatures, respectively. RpoE regulon genes are involved in various processes associated with bacterial signal transduction, membrane homeostasis, energy metabolism and virulence. In particular, RpoE positively controlled expression of csrA encoding an RNA binding protein essential for central carbon metabolism. In addition, P. plecoglossicida RpoE was validated to regulate type VI secretion system (T6SS) expression, bacteria competition, biofilm formation and reproduction in macrophages. Collectively, RpoE-centered RIP cascade appeared to play important roles in control of the expression of genes involved in adaptation in vivo and in vitro niches by thermal sensing in P. plecoglossicida. These results facilitates to reveal the pathogenic mechanisms of P. plecoglossicida causing fish diseases and provides new perspectives to control bacterial infection.

Efficacy and safety of neoadjuvant immunotherapy in resectable esophageal or gastroesophageal junction carcinoma: A pooled analysis of prospective clinical trials.

Neoadjuvant chemoradiotherapy (NCRT) plus radical esophagectomy is currently the standard treatment for resectable esophageal or gastroesophageal junction (GEJ) carcinoma. The aim of this study is to evaluate the efficacy and safety of neoadjuvant immunotherapy in resectable esophageal or GEJ carcinoma. Prospective clinical trials investigating efficacy and/or safety of neoadjuvant immunotherapy with immune checkpoint inhibitors (ICIs) followed by radical esophagectomy in patients with newly diagnosed resectable esophageal or GEJ carcinoma were identified through literature search. Quality assessment was performed by using the Newcastle-Ottawa scale. Preliminary treatment outcomes of pathologically complete response (pCR, ypT0N0) and grade 3-4 adverse effects (AEs) were pooled together and then compared with standard NCRT of the historical control CROSS study by Chi-square (χ2) test. A two-sided P value < 0.05 was considered statistically significant. A total of 17 eligible non-randomized trials with 455 participants were included into analysis. The most common primary endpoint was pCR (n = 7, 41%), and the median sample size and follow-up period was 23 patients and 7.9 months, respectively. For patients receiving neoadjuvant immunotherapy, the overall pCR, R0 resection, and grade 3-4 AE rates were 33.2%, 95.5%, and 35.1%, respectively. For esophageal squamous cell carcinoma (ESCC) and adenocarcinoma (EAC), neoadjuvant immunochemoradiotherapy showed no significant improvement in pCR rate than NCRT (ESCC, 50% vs 48.7%, P = 0.9; EAC, 32.6% vs 23.1%, P = 0.22). Grade 3-4 AEs were the most common in patients with neoadjuvant immunochemoradiotherapy, significantly higher than immunochemotherapy (46.7% vs 32.8%, P = 0.04) and NCRT (46.7% vs 18.1%, P < 0.0001). In conclusion, for patients with resectable esophageal or GEJ carcinoma, the addition of ICIs to standard NCRT could not improve pCR rate in both ESCC and EAC, but significantly increased the risk of severe AEs. Large-scale phase 3 randomized trials were urgently needed to further confirm the survival benefit and safety profile of neoadjuvant immunotherapy.

Retrospective Study on Left-Sided Breast Radiotherapy: Dosimetric Results and Correlation with Physical Factors for Free Breathing and Breath Hold Irradiation Techniques.

Objectives: In breast radiotherapy, the proximity of the target to sensitive structures together with the uncertainty introduced by respiratory movement, make this treatment one of the most studied to increase its effectiveness. Dosimetric and physical variables play an important role and the study of their correlation and impact on treatment is fundamental. This retrospective study aims to highlight the dosimetric differences of 2 different clinical data sets of patients receiving left-sided breast irradiation in free breathing (FB) or breath hold (BH). Methods: A total of 155 left breast carcinoma patients receiving whole-breast irradiation in FB (73 patients) and BH (82 patients) were enrolled in this study. The dosimetric parameters of the target, heart, left and right lung and right breast were evaluated and compared, and possible correlations were studied in both groups. Results: No significant difference (P > .05) was found in the target dosimetry; a clear advantage in BH for both high and low doses received by the heart, with reductions of the dosimetric parameters between 27.1% and 100% (P < .003); for the left lung reductions decreased with increasing dose (-22.4% and -13.4% for doses of 5 and 20 Gy, respectively, P < .003). Conclusion: Significant correlations for BH treatments were registered between the volumes of the target and left lung, and the dosimetric parameters of the heart and left lung. BH treatment brings significant dosimetric advantages to organs at risk for a wide range of patients with different anatomy, target volumes and lung capacity, with additional benefits for small-sized breasts and important lung capacity.

Feasibility of using calibrated cone-beam computed tomography scans to validate the heart dose in left breast post-mastectomy radiotherapy.

OBJECTIVE: In post-mastectomy radiotherapy, high-conformal techniques are a valid method for determining the dose distribution around a target. However, the proximity of critical structures is a reason for concern. This study aims to evaluate the feasibility of using calibrated cone-beam computed tomography (CBCT) scans as a valid tool for a timely heart dose evaluation. METHODS: A retrospective analysis was conducted on 170 retrospective CBCT scans of 17 patients who underwent high-conformal post-mastectomy irradiation. The delivered doses that were calculated using personalized calibrated CBCT were compared with the doses planned, using the dose-volume histogram dosimetric parameters. RESULTS: The heart volume that was evaluated using CBCT presented a mean increase of 6%; this discrepancy impacted the heart dose in 4 of 17 patients, with an absolute increase of V25 Gy (range, 2.5%-7.6%) and an increase in the mean dose (range, 1.1-3.4 Gy). The dose for the target, ipsilateral lung, and contralateral breast remained unchanged. CONCLUSION: Using CBCT to monitor the dose that is delivered to the heart is feasible, allowing for a timely shift to an adaptive plan if clinically necessary.

Evaluation of interfraction setup variations for postmastectomy radiation therapy using EPID-based in vivo dosimetry.

Postmastectomy radiation therapy is technically difficult and can be considered one of the most complex techniques concerning patient setup reproducibility. Slight patient setup variations - particularly when high-conformal treatment techniques are used - can adversely affect the accuracy of the delivered dose and the patient outcome. This research aims to investigate the inter-fraction setup variations occurring in two different scenarios of clinical practice: at the reference and at the current patient setups, when an image-guided system is used or not used, respectively. The results were used with the secondary aim of assessing the robustness of the patient setup procedure in use. Forty eight patients treated with volumetric modulated arc and intensity modulated therapies were included in this study. EPID-based in vivo dosimetry (IVD) was performed at the reference setup concomitantly with the weekly cone beam computed tomography acquisition and during the daily current setup. Three indices were analyzed: the ratio R between the reconstructed and planned isocenter doses, γ % and the mean value of γ from a transit dosimetry based on a two-dimensional γ -analysis of the electronic portal images using 5% and 5 mm as dose difference and distance to agreement gamma criteria; they were considered in tolerance if R was within 5%, γ % > 90% and γ mean  < 0.4. One thousand and sixteen EPID-based IVD were analyzed and 6.3% resulted out of the tolerance level. Setup errors represented the main cause of this off tolerance with an occurrence rate of 72.2%. The percentage of results out of tolerance obtained at the current setup was three times greater (9.5% vs 3.1%) than the one obtained at the reference setup, indicating weaknesses in the setup procedure. This study highlights an EPID-based IVD system's utility in the radiotherapy routine as part of the patient's treatment quality controls and to optimize (or confirm) the performed setup procedures' accuracy.

Characterization of a prognostic four­gene methylation signature associated with radiotherapy for head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) remains one of the most common malignancies associated with poor prognosis. DNA methylation has emerged as an important mechanism underlying the radio­resistance of tumors. Prognostic biomarkers based on radiotherapy­related aberrant DNA methylation are limited. Methylation profiles of 388 patients with HNSCC were acquired from The Cancer Genome Atlas (TCGA) portal. Genes with differentially methylated CpG sites (DMGs) were screened between patients with a favorable and poor prognosis with or without radiotherapy. A weight gene co­methylation network was constructed using a Weighted Gene Co­expression Network Analysis (WGCNA) package. A lasso Cox­PH model was used to identify the optimal panel of genes with the ability to predict survival in these patients. Prognostic performance of the multi­gene methylation signature was assessed in a training set and confirmed in a validation set. A total of 976 DMGs were observed between favorable and poor prognostic samples. Four DMG­enriched co­methylation modules were identified. A four­gene methylation signature was determined by the lasso Cox­PH model that consisted of ZNF10, TMPRSS12, ERGIC2, and RNF215. The risk score based on the four­gene signature was able to divide the training or validation set into two risk groups with significantly different overall survival. Thus, the present study revealed a radiotherapy­related four­gene methylation signature to predict survival outcomes of patients with HNSCC, providing candidate therapeutic targets for novel therapy against HNSCC. However, substantial validation experiments are required.

Response of Fingernail Growth to Out-of-Field Low-Dose X ray in Cancer Patients Receiving Radiotherapy.

The entire body of a patient with cancer is exposed to low-dose levels of radiation (mGy) during radiation therapy. The safety and biological impact of such exposure to low-dose radiation on the human body are largely unknown. The fingernail is a highly proliferative tissue, and its growth can be monitored during radiation treatment to analyze early effects of low-dose radiation. The fingernails of 30 patients who received external beam radiotherapy (EBRT) were used in this study to investigate the change in nail growth during fractionated radiotherapy. Lead shields were applied to some fingers to create dose variance within individual patients. The absorbed dose was measured, and the relationship between the dose and change in nail growth rate was analyzed. Other factors, including serum albumin, hemoglobin level, body weight index, age, gender and chemotherapy, were also subjected to multivariate analysis. Fingernails from patients received an average of 0.96 mGy per treatment fraction. We observed a surprising decline in fingernail growth rate during radiotherapy, which was more prominent in the nonshielded fingernails with a relatively high-absorbed dose. Such growth delay could be observed as early as one week postirradiation and lasted the entire treatment course. Using fingernail growth as a novel marker for radioresponse, the current study showed that exposure to very low-dose ionizing radiation has previously unrecognized early effects on human tissue.

[Expression and Significance of bag-1, bcl-2 in Non-small Cell Lung Cancer and the Correlation with Multi-drug Resistance.].

BACKGROUND: bag-1, bcl-2 and bax are all apoptosis-related proteins. They play a role in the diagnosis, progress, metastasis and prognosis of tumor. The aim of the study was to investigate the expression of bag-1, bcl-2 and bax in non-small cell lung cancer, and to study the relationship between their expression levels and the clinical pathological characteristics, furthermore, to evaluate their correlation with multi-drug resistance. METHODS: The expressions of bag-1, bcl-2 and bax in 140 non-small cell lung cancer tissues (40 of 140 were processed neoadjuvant chemotherapy) and 15 lung benign lesion tissues were examined with SP immuno-histochemical stain. RESULTS: The positive expression rates of bag-1 and bcl-2 protein in non-small cell lung cancer were significantly higher than those in pulmonary benign lesion tissues (P<0.05), but the positive expression rate of bax in non-small cell lung cancer was significantly lower than that in pulmonary benign lesion tissues (P<0.05). The expressions of bag-1, bcl-2 and bax protein were not related to the age and sex of patients, histological classification, P-TNM stage and lymph node involvement of the cancer (P>0.05), but bag-1 was related to the differentiation degree of the tumor. The lower the differentiation was, the higher the levels of expression of bag-1 were. bcl-2 protein expression was highly positive correlated with the bag-1 protein expression in non-small cell lung cancer (r =0.371, P<0.01), and bcl-2 protein was highly negative correlated with bax protein expression (r=-0.225, P<0.01). The positive expression rates of bag-1 and bcl-2 showed increasing trends from the patients without neoadjuvant therapy to those with neoadjuvant therapy, but the difference had no statistic significance (P>0.05). CONCLUSIONS: The high expression of bag-1, bcl-2 protein and the low expression of bax protein exist in nonsmall cell lung cancer. The expression level of bag-1 protein is closely related to the differentiation degree of non-small cell lung cancer. A highly positive correlation exists between bag-1 and bcl-2 expression, and a highly negative correlation is observed between bcl-2 and bax expression. The study doesn't provide the evidence that there is a close correlation between the expression levels of bag-1, bcl-2, bax and the multi-drug resistance in non-small cell lung cancer.

[The mechanism of metastasis suppressor gene nm23-H1 involving in the Ras signaling of lung cancer.].

BACKGROUND: It has been confirmed that nm23-H1 gene is one of the tumor metastasis suppressor genes. Up to now, the exact mechanism of nm23-H1 gebe is uncertain. The aim of this study the mechanism of metastasis suppressor gene nm23-H1 involving in the Ras signaling of lung cancer. METHODS: The wild and mutant type of pEGFP-nm23-H1 plasmids [WT (wild type), H118F, S120G, P96S, S44A] were transfected into the L9981 lung cancer cell lines through liposome method, and the complex of KSR and nm23-H1 was detected through co-immunoprecipitation and Western blot assay. RESULTS: The human KSR could be detected in the nm23-H1 immunoprecipitations in all the trasfected L9981 lung cancer cell lines. But no significant difference of KSR expression was found in the wild and mutant nm23-H1 trasfected cell lines (F =0.190, P =0.938). CONCLUSIONS: There was a close interaction between nm23-H1 and KSR, which was independent of the nm23-H1 mutation. Nm23-H1 involving in the Ras signaling of lung cancer may be through the KSR gene.

[Construction of eukaryotic expression vectors of carboxyl terminus and amino terminus of kinase suppressor of Ras (KSR) and their expression in 293T cell line].

BACKGROUND: The present experimental data have showed that the function of kinase suppressor of Ras (KSR) is mainly as a scaffold protein that coordinates the assembly of a multiprotein complex containing MAPK and its upstream regulators. But whether KSR has kinase activity is still the point of argument until now. The aim of this study is to construct eukaryotic expression vectors of carboxyl terminus and amino terminus of KSR and to detect their expression in 293T cell line. METHODS: N-KSR and C-KSR were amplified by PCR. The eukaryotic expression vectors of pCMV-Tag2b-N-KSR and pCMV-Tag2b-C-KSR were constructed by gene recombination technique and the recombinant plasmids were verified by restriction enzyme analysis and sequencing. Then positive clones were transfected into 293T cell line. Expression of target proteins was analyzed by Western blot. RESULTS: The sequences and open read frames of the two vectors were both completely concordant with experiment design. The target proteins could be observed in transfected 293T cells by Western blot. CONCLUSIONS: Eukaryotic expression vectors of pCMV-Tag2b-N-KSR and pCMV-Tag2b-C-KSR are successfully constructed, and they can be expressed in 293T cells. It provides an experimental base for further research work.