Geometrical Comparison and Quantitative Evaluation of 18F-FDG PET/CT- and DW-MRI-Based Target Delineation Before and During Radiotherapy for Esophageal Squamous Carcinoma

Background and PurposeThis study aimed to evaluate the geometrical differences in and metabolic parameters of 18F-fluorodeoxyglucose positron emission tomography–computed tomography (18F-FDG PET-CT) and diffusion-weighted magnetic resonance imaging (DW-MRI) performed before and during radiotherapy (RT) for patients with esophageal cancer based on the three-dimensional CT (3DCT) medium and explore whether the high signal area derived from DW-MRI can be used as a tool for an individualized definition of the volume in need of dose escalation for esophageal squamous cancer.Materials and MethodsThirty-two patients with esophageal squamous cancer sequentially underwent repeated 3DCT, 18F-FDG PET-CT, and enhanced MRI before the initiation of RT and after the 15th fraction. All images were fused with 3DCT images through deformable registration. The gross tumor volume (GTV) was delineated based on PET Edge on the first and second PET-CT images and defined as GTVPETpre and GTVPETdur, respectively. GTVDWIpre and GTVDWIdur were delineated on the first and second DWI and corresponding T2-weighted MRI (T2W-MRI)-fused images. The maximum, mean, and peak standardized uptake values (SUVs; SUVmax, SUVmean, and SUVpeak, respectively); metabolic tumor volume (MTV); and total lesion glycolysis(TLG) and its relative changes were calculated automatically on PET. Similarly, the minimum and mean apparent diffusion coefficient (ADC; ADCmin and ADCmean) and its relative changes were measured manually using ADC maps.ResultsThe volume of GTVCT exhibited a significant positive correlation with that of GTVPET and GTVDWI (both p < 0.001). Significant differences were observed in both ADCs and 18F-FDG PET metabolic parameters before and during RT (both p < 0.001). No significant correlation was observed between SUVs and ADCs before and during RT (p = 0.072–0.944) and between ∆ADCs and ∆SUVs (p = 0.238–0.854). The conformity index and degree of inclusion of GTVPETpre to GTVDWIpre were significantly higher than those of GTVPETdur to GTVDWIdur (both p < 0.001). The maximum diameter shrinkage rate (∆LDDWI) (24%) and the tumor volume shrinkage rate (VRRDWI) (60%) based on DW-MRI during RT were significantly greater than the corresponding PET-based ∆LDPET (14%) and VRRPET (41%) rates (p = 0.017 and 0.000, respectively).ConclusionBased on the medium of CT images, there are significant differences in spatial position, biometabolic characteristics, and the tumor shrinkage rate for GTVs derived from 18F-FDG PET-CT and DW-MRI before and during RT for esophageal squamous cancer. Further studies are needed to determine if DW-MRI will be used as tool for an individualized definition of the volume in need of dose escalation.

A predominant enhancer co-amplified with the SOX2 oncogene is necessary and sufficient for its expression in squamous cancer

Amplification and overexpression of the SOX2 oncogene represent a hallmark of squamous cancers originating from diverse tissue types. Here, we find that squamous cancers selectively amplify a 3’ noncoding region together with SOX2, which harbors squamous cancer-specific chromatin accessible regions. We identify a single enhancer e1 that predominantly drives SOX2 expression. Repression of e1 in SOX2-high cells causes collapse of the surrounding enhancers, remarkable reduction in SOX2 expression, and a global transcriptional change reminiscent of SOX2 knockout. The e1 enhancer is driven by a combination of transcription factors including SOX2 itself and the AP-1 complex, which facilitates recruitment of the co-activator BRD4. CRISPR-mediated activation of e1 in SOX2-low cells is sufficient to rebuild the e1-SOX2 loop and activate SOX2 expression. Our study shows that squamous cancers selectively amplify a predominant enhancer to drive SOX2 overexpression, uncovering functional links among enhancer activation, chromatin looping, and lineage-specific copy number amplifications of oncogenes.

Pronounced Enhancement in Radiosensitization of Esophagus Cancer Cultivated in Docosahexaenoic Acid Via The PPAR-γ Activation

Background: Docosahexaenoic acid (DHA) has been reported to slow the tumor growth and improve prognosis, and been used to co-operate with many other chemotherapy medicines. Up to now, survey focuses on the interaction between DHA and radiation is relatively modest. Our study sought to evaluate the changes of radiosensitivity caused by DHA on esophageal cancer cells. Besides, potential mechanism and molecular are needed to be explored.Results：DHA enhanced proliferation inhibition of irradiation on esophageal cancer cells. DNA damage, especially double-strand break, induced by irradiation, was sharply increased by DHA addition. DHA accelerated G2/M phase blocking, cell apoptosis and lipid peroxidation after radiotherapy. The similar outcomings were observed in mouse xenograft tumor experiment that the malignancy substantially dismissed after the combined treatment of DHA and irradiation. Moreover, PPAR -γ was verified to increase post-treatment. Suppression of PPAR -γ would attenuate the radio sensitization triggered by DHA incompletely.Conclusion：DHA could improve radio sensitivity in esophageal squamous cancer cells in vivo and in vitro by activating PPAR -γ. Due to its explicitly usage and convenient, DHA and other PPAR -γ agonists would serve as an adjuvant therapy before radiotherapy if the clinical trials indicated positive from now on.

Human Telomerase Reverse Transcriptase as a Therapeutic Target of Dihydroartemisinin for Esophageal Squamous Cancer

Objective: To elucidate the oncogenic role of human telomerase reverse transcriptase (hTERT) in esophageal squamous cancer and unravel the therapeutic role and molecular mechanism of dihydroartemisinin (DHA) by targeting hTERT.Methods: The expression of hTERT in esophageal squamous cancer and the patients prognosis were analyzed by bioinformatic analysis from TCGA database, and further validated with esophageal squamous cancer tissues in our cohort. The Cell Counting Kit-8 (CCK8) and colony formation assay were used to evaluate the proliferation of esophageal squamous cancer cell lines (Eca109, KYSE150, and TE1) after hTERT overexpression or treated with indicated concentrations of DHA. Transwell migration assay and scratch assay were employed to determine the migration abilities of cancer cells. Fluorescence microscopy and flow cytometry were conducted to measure the intracellular reactive oxygen species (ROS) levels in cancer cells after treated with DHA. Moreover, RT-PCR and Western blot were performed to test the alteration of associated genes on mRNA and protein level in DHA treated esophageal squamous cancer cell lines, respectively. Furthermore, tumor-bearing nude mice were employed to evaluate the anticancer effect of DHA in vivo.Results: We found that hTERT was significantly upregulated in esophageal squamous cancer both from TCGA database and our cohort also. Overexpression of hTERT evidently promoted the proliferation and migration of esophageal squamous cancer cells in vitro. Moreover, DHA could significantly inhibit the proliferation and migration of esophageal cancer cell lines Eca109, KYSE150, and TE1 in vitro, and significantly down-regulate the expression of hTERT on both mRNA and protein level in a time- and dose-dependent manner as well. Further studies showed that DHA could induce intracellular ROS production in esophageal cancer cells and down-regulate SP1 expression, a transcription factor that bound to the promoter region of hTERT gene. Moreover, overexpression of SP1 evidently promoted the proliferation and migration of Eca109 and TE1 cells. Intriguingly, rescue experiments showed that inhibiting ROS by NAC alleviated the downregulation of SP1 and hTERT in cells treated with DHA. Furthermore, overexpression of SP1 or hTERT could attenuate the inhibition effect of DHA on the proliferation and migration of Eca109 cells. In tumor-bearing nude mice model, DHA significantly inhibited the growth of esophageal squamous cancer xenografts, and downregulated the expression of SP1 and hTERT protein, while no side effects were observed from heart, kidney, liver, and lung tissues by HE stain.Conclusion: hTERT plays an oncogenic role in esophageal squamous cancer and might be a therapeutic target of DHA through regulating ROS/SP1 pathway.

USP28: Oncogene or Tumor Suppressor? A Unifying Paradigm for Squamous Cell Carcinoma

Squamous cell carcinomas are therapeutically challenging tumor entities. Low response rates to radiotherapy and chemotherapy are commonly observed in squamous patients and, accordingly, the mortality rate is relatively high compared to other tumor entities. Recently, targeting USP28 has been emerged as a potential alternative to improve the therapeutic response and clinical outcomes of squamous patients. USP28 is a catalytically active deubiquitinase that governs a plethora of biological processes, including cellular proliferation, DNA damage repair, apoptosis and oncogenesis. In squamous cell carcinoma, USP28 is strongly expressed and stabilizes the essential squamous transcription factor ΔNp63, together with important oncogenic factors, such as NOTCH1, c-MYC and c-JUN. It is presumed that USP28 is an oncoprotein; however, recent data suggest that the deubiquitinase also has an antineoplastic effect regulating important tumor suppressor proteins, such as p53 and CHK2. In this review, we discuss: 1) The emerging role of USP28 in cancer. 2) The complexity and mutational landscape of squamous tumors. 3) The genetic alterations and cellular pathways that determine the function of USP28 in squamous cancer. 4) The development and current state of novel USP28 inhibitors.

Poland Syndrome Associated with Lung Cancer: A Case Report and Literature Review

Background: Poland syndrome is a rare congenital disease consisting a spectrum of defects occupied by unilateral chest wall hypoplasia and ipsilateral hand abnormalities. It is also closely associated with some malignant diseases and some benign diseases, such as breast cancer, lymphoma, recurrent spontaneous pneumothorax, perforating dermatosis, hemangioma, gastric cancer and lung cancer. The low incidence of Poland syndrome has hindered investigators’ attempts to develop randomized prospective trials, so the disease is poorly understood. Now We find out a case of Poland’s syndrome associated with adenocarcinoma of right lung, in which before this article there was only article depicting a case of lung squamous cancer with poland syndrome, this is an interesting topic. To the best of our knowledge, this is the second case of poland syndrome closely related to lung cancer.Case presentation: A 61-year-old man came to the hospital accompanied by intermittent dry cough and hemoptysis that lasted for 2 months. Chest CT revealed showed a large lobulated mass about 5.5cm × 4.0 cm × 3.0 cm in the right lower lung field and the normal right pectoralis major muscle and pectoralis minor were both absent. we diagnosed the patient with stage IIIa lung adenocarcinoma. After two cycles of preoperative platinum-doublet chemotherapy, we have performed a regular right lower lobectomy and lymph node dissection. Until now, after 2.5 years of follow up, he did not relapse.Conclusions: In addition to some other reported types of malignancies, there is increasing evidence that an association between these two clinical entities. Although we do not understand the underlying mechanisms, we assume there exists some common gene pathways that regulate these two clinical entities. Because these patients who got Poland syndrome are susceptibility to different kinds of malignancies, longitudinal epidemiological studies may be needed.