Prognostic value and predictive threshold of tumor volume for patients with locally advanced nasopharyngeal carcinoma receiving intensity-modulated radiotherapy

Background: Gross target volume of primary tumor(GTV?P) is very important for the prognosis prediction of patients with nasopharyngeal carcinoma(NPC), but it is unknown whether the same is true for locally advanced NPC patients treated with intensity?modulated radiotherapy(IMRT). This study aimed to clarify the prognostic value of tumor volume for patient with locally advanced NPC receiving IMRT and to ind a suitable cut?of value of GTV?P for prognosis prediction.Methods: Clinical data of 358 patients with locally advanced NPC who received IMRT were reviewed. Receiver oper?ating characteristic(ROC) curves were used to identify the cut?of values of GTV?P for the prediction of diferent end?points [overall survival(OS), local relapse?free survival(LRFS), distant metastasis?free survival(DMFS), and disease?free survival(DFS)] and to test the prognostic value of GTV?P when compared with that of the American Joint Committee on Cancer T staging system.Results: The 358 patients with locally advanced NPC were divided into two groups by the cut?of value of GTV?P as determined using ROC curves: 219(61.2%) patients with GTV?P ≤46.4 mL and 139(38.8%) with GTV?P >46.4 mL. The 3?year OS, LRFS, DMFS, and DFS rates were all higher in patients with GTV?P ≤46.4 mL than in those with GTV?P > 46.4 mL(all P < 0.05). Multivariate analysis indicated that GTV?P >46.4 mL was an independent unfavorable prognostic factor for patient survival. The ROC curve veriied that the predictive ability of GTV?P was superior to that of T category(P < 0.001). The cut?of values of GTV?P for the prediction of OS, LRFS, DMFS, and DFS were 46.4, 57.9, 75.4 and 46.4 mL, respectively.Conclusion: In patients with locally advanced NPC, GTV?P >46.4 mL is an independent unfavorable prognostic indi?cator for survival after IMRT, with a prognostic value superior to that of T category.

Photodynamic therapy for middle-advanced stage upper gastrointestinal carcinomas: A systematic review and meta-analysis

AIM To determine the therapeutic effect of photodynamic therapy(PDT) for middle-advanced stage upper gastrointestinal carcinomas. METHODS We searched PubM ed, EMBASE, the Cochrane Library, China National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang Database from inception to April 2018 for randomized controlled studies. These studies compared PDT with other palliative therapies(radiotherapy, chemotherapy, or Nd:YAG laser) and compared PDT, radiotherapy, or chemotherapy alone with PDT combined with chemotherapy/radiotherapy. In our meta-analysis, both fixed and random effects models were used to estimate the risk ratio(RR) for dichotomous outcomes(the response rate and one-year survival rate).RESULTS Ten random controlled clinical studies with 953 patients were included in the analysis. The effective rate for PDT was better than that of radiotherapy or Nd:YAG laser for the treatment of middle-advanced upper gastrointestinal carcinomas [RR = 1.36; 95% confidence interval(CI): 1.13-1.65; P = 0.001]. In addition, PDT combined with chemotherapy had significantly better efficacy and a higher one-year survival rate than PDT or chemotherapy alone(significant remission rate, RR = 1.62; 95%CI: 1.34-1.97; P < 0.00001; one-year survival rate, RR = 1.81; 95%CI: 1.13-2.89; P = 0.01).CONCLUSION PDT is a useful method for the treatment of middleadvanced stage upper gastrointestinal carcinomas. PDT combined with chemotherapy or radiotherapy can enhance its efficacy and prolong survival time.

Novel perspective in pancreatic cancer therapy:Targeting ferroptosis pathway

Pancreatic cancer is a highly lethal malignancy with low resection and survival rates and is not sensitive to radiotherapy and chemotherapy.Ferroptosis is a novel form of nonapoptotic regulated cell death characterized by the accumulation of lipid peroxides and reactive oxygen species involved in iron metabolism.Ferroptosis has a significant role in the occurrence and development of various tumors.Previous studies have shown that regulating ferroptosis-induced cell death inhibited tumor growth in pancreatic cancer and was synergistic with other antitumor drugs to improve treatment sensitivity.Herein,we discuss the mechanism,inducers,and developments of ferroptosis in pancreatic cancer to provide new strategies for the treatment of the malignancy.

Photodynamic therapy regulates fate of cancer stem cells through reactive oxygen species

Photodynamic therapy(PDT)is an effective and promising cancer treatment.PDT directly generates reactive oxygen species(ROS)through photochemical reactions.This oxygen-dependent exogenous ROS has anti-cancer stem cell(CSC)effect.In addition,PDT may also increase ROS production by altering metabolism,endoplasmic reticulum stress,or potential of mitochondrial membrane.It is known that the half-life of ROS in PDT is short,with high reactivity and limited diffusion distance.Therefore,the main targeting position of PDT is often the subcellular localization of photosensitizers,which is helpful for us to explain how PDT affects CSC characteristics,including differentiation,selfrenewal,apoptosis,autophagy,and immunogenicity.Broadly speaking,excess ROS will damage the redox system and cause oxidative damage to molecules such as DNA,change mitochondrial permeability,activate unfolded protein response,autophagy,and CSC resting state.Therefore,understanding the molecular mechanism by which ROS affect CSCs is beneficial to improve the efficiency of PDT and prevent tumor recurrence and metastasis.In this article,we review the effects of two types of photochemical reactions on PDT,the metabolic processes,and the biological effects of ROS in different subcellular locations on CSCs.

Shielding of the geomagnetic field reduces hydrogen peroxide production in human neuroblastoma cell and inhibits the activity of CuZn superoxide dismutase

Accumulative evidence has shown the adverse effects of a geomagnetic field shielded condition, so called a hypomagnetic field （HMF）, on the metabolic processes and oxidative stress in animals and cells. However, the underlying mechanism remains unclear. In this study, we evaluate the role of HMF on the regulation of cellular reactive oxygen species （ROS） in human neuroblastoma SH-SY5Y cells. We found that HMF exposure led to ROS decrease, and that restoring the decrease by additional H2O2 rescued the HMF-enhanced cell proliferation. The measurements on ROS related indexes, including total anti-oxidant capacity, H2O2 and superoxide anion levels, and superoxide dismutase （SOD） activity and expres- sion, indicated that the HMF reduced H2O2 production and inhibited the activity of CuZn-SOD. Moreover, the HMF accelerated the denaturation of CuZn-SOD as well as enhanced aggregation of CuZn-SOD protein, in vitro. Our findings indicate that CuZn-SOD is able to response to the HMF stress and suggest it a mediator of the HMF effect.

Experimental verification of group non-membership in optical circuits

The class quantum Merlin–Arthur(QMA),as the quantum analog of nondeterministic polynomial time,contains the decision problems whose YES instance can be verified efficiently with a quantum computer.The problem of deciding the group non-membership(GNM)of a group element is conjectured to be a member of QMA.Previous works on the verification of GNM,which still lacks experimental demonstration,required a quantum circuit with O(n~5)group oracle calls.Here,we provide an efficient way to verify GNM problems,in which each quantum circuit only contains O(1)group of oracle calls,and the number of qubits in each circuit is reduced by half.Based on this protocol,we then experimentally demonstrate the new verification process with a four-element group in an all-optical circuit.The new protocol is validated experimentally by observing a significant completeness-soundness gap between the probabilities of accepting elements in and outside the subgroup.This work efficiently simplifies the verification of GNM and is helpful in constructing more quantum protocols based on the near-term quantum devices.