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Xiaqing Xu, Meimei Si, Honggang Lou, Youyou Yan, Yunxi Liu, Hong Zhu, Xiaoe Lou, Jian Ma, Difeng Zhu, Honghai Wu, Bo Yanz, Haoshu Wu, Ling Ding, and Qiaojun He

Free access

Wei-Chun Chang, Hsiao-Ching Wang, Wei-Chung Cheng, Juan-Cheng Yang, Wei-Min Chung, Yen-Pin Ho, Lumin Chen, Yao-Ching Hung, and Wen-Lung Ma

Platinum-based therapy remains the cornerstone for cancer therapy; however, its efficacy varies. The role of lipoprotein receptor-mediated lipid entry for cancer development has been reported. Yet, the roles and mechanism of the low-density lipoprotein receptor (LDLR) in chemo-sensitivities are unknown. In the current report, we used epithelial ovarian cancer (EOC), composed of various cellularities, to study this issue. Using public cDNA microarray database and single cohort study, LDLR expressions were positively associated with epithelial ovarian carcinomas (EOCs) platinum-based chemotherapy patients’ disease prognosis. In vitro and in vivo add-in/silencing LDLR was introduced to determine cisplatin sensitivity and cancer growth. Results revealed that knocked-down LDLR could sensitize while overexpressed LDLR could insensitize EOC cells to the cytotoxic effects of cisplatin. Moreover, the trans-omics approaches depicted an LDLR→LPC (Lyso-phosphatidylcholine)→FAM83B (phospholipase-related)→FGFRs (cisplatin sensitivity and phospholipase-related) regulatory axis. Finally, the manipulation of LDLR expression in EOC cells was found to determine the efficacy of cisplatin therapy in terms of tumor suppression. In conclusion, the LDLR→LPC→FAM83B→FGFRs axis is an example of tumor macroenvironmental regulation of therapy outcomes. Relatedly, LDLR expression could serve as a biomarker of chemotherapy sensitivity in EOCs. Significance: this study describes the role of LDLR in the development of insensitivity to platinum-based chemotherapy in epithelial ovarian cancer. The lipidome (e.g., LPC) and transcriptome (e.g., FAM38B) interactions revealed using trans-omics approaches an LDLR→LPC→FAM83B→FGFRs regulatory axis in cancer cells, in an animal model, and in patients.

Open access

Jonathan Wesley Nyce

We have recently described in this journal our detection of an anthropoid primate-specific, adrenal androgen-dependent, p53-mediated, ‘kill switch’ tumor suppression mechanism that reached its fullest expression only in humans, as a result of human-specific exposure to polycyclic aromatic hydrocarbons caused by the harnessing of fire – but which has components reaching all the way back to the origin of the primate lineage. We proposed that species-specific mechanisms of tumor suppression are a generalized requirement for vertebrate species to increase in body size or lifespan beyond those of species basal to their lineage or to exploit environmental niches which increase exposure to carcinogenic substances. Using empirical dynamic modeling, we have also reported our detection of a relationship between body size, lifespan, and species-specific mechanism of tumor suppression (and here add carcinogen exposure), such that a change in any one of these variables requires an equilibrating change in one or more of the others in order to maintain lifetime cancer risk at a value of about 4%, as observed in virtually all larger, longer-lived species under natural conditions. Here we show how this relationship, which we refer to as the lex naturalis of vertebrate speciation, elucidates the evolutionary steps underlying an adrenal androgen-dependent, human-specific ‘kill switch’ tumor suppression mechanism; and further, how it prescribes a solution to ‘normalize’ lifetime cancer risk in our species from its current aberrant 40% to the 4% that characterized primitive humans. We further argue that this prescription writ by the lex naturalis represents the only tenable strategy for meaningful suppression of the accelerating impact of cancer upon our species.

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Laura Valerio, Valeria Bottici, Antonio Matrone, Paolo Piaggi, David Viola, Virginia Cappagli, Laura Agate, Eleonora Molinaro, Raffaele Ciampi, Alessia Tacito, Teresa Ramone, Cristina Romei, and Rossella Elisei

Vandetanib is an important treatment option for advanced metastatic medullary thyroid cancer. The aims of this study were to evaluate the predictors of both a longer response to vandetanib and the outcome. Medical records of 79 medullary thyroid cancer patients treated with vandetanib at our center were analysed. Twenty-five patients were treated for <12 months, 54 were treated for ≥12 months and 24 of these latter were treated for ≥48 months (short-, long- and very long-term). The median progression free survival of the long and very long-term treated patients was significantly longer than in the ZETA trial. When comparing the groups of short - and long-term treated patients the only significant difference was that these latter were less frequently previously treated with a tyrosine kinase inhibitor. However, the long-term treated patients had a younger age, both at diagnosis and enrolment, which was statistically significant in the very long-term treated patients. In the long-term treated group, younger age, enrolment for symptoms and development of adverse events were significantly correlated with a better outcome. The enrolment for symptoms remained the only statistically significant predictor of a good outcome in the very long-term treated patients. In conclusion, early treatment with vandetanib, when patients are younger, with a good ECOG performance status and symptomatic disease, not necessarily progressing for RECIST, seem to be the best predictors of a longer and durable response. Further studies are needed to confirm these results.

Free access

Mason A Lee, Kensey N Bergdorf, Courtney J Phifer, Caroline Y Jones, Sonia Y Byon, Leah M Sawyer, Joshua A Bauer, and Vivian L Weiss

Thyroid cancer has the fastest growing incidence of any cancer in the United States, as measured by the number of new cases per year. Despite advances in tissue culture techniques, a robust model for thyroid cancer spheroid culture is yet to be developed. Using eight established thyroid cancer cell lines, we created an efficient and cost-effective 3D culture system that can enhance our understanding of in vivo treatment response. We found that all eight cell lines readily form spheroids in culture with unique morphology, size, and cytoskeletal organization. In addition, we developed a high-throughput workflow that allows for drug screening of spheroids. Using this approach, we found that spheroids from K1 and TPC1 cells demonstrate significant differences in their sensitivities to dabrafenib treatment that closely model expected patient drug response. In addition, K1 spheroids have increased sensitivity to dabrafenib when compared to monolayer K1 cultures. Utilizing traditional 2D cultures of these cell lines, we evaluated the mechanisms of this drug response, showing dramatic and acute changes in their actin cytoskeleton as well as inhibition of migratory behavior in response to dabrafenib treatment. Our study is the first to describe the development of a robust spheroid system from established cultured thyroid cancer cell lines and adaptation to a high-throughput format. We show that combining 3D culture with traditional 2D methods provides a complementary and powerful approach to uncover drug sensitivity and mechanisms of inhibition in thyroid cancer.

Free access

Nidal Muhanna, Harley H L Chan, Jason L Townson, Cheng S Jin, Lili Ding, Michael S Valic, Catriona M Douglas, Christina M MacLaughlin, Juan Chen, Gang Zheng, and Jonathan C Irish

The incidence of differentiated thyroid cancer has increased significantly during the last several decades. Surgical resection is the primary treatment for thyroid cancer and is highly effective, resulting in 5-year survival rates greater than 98%. However, surgical resection can result in short- and long-term treatment-related morbidities. Additionally, as this malignancy often affects women less than 40 years of age, there is interest in more conservative treatment approaches and, an unmet need for therapeutic options that minimize the risk of surgery-related morbidities while simultaneously providing an effective cancer treatment. Photodynamic therapy (PDT) has the potential to reduce treatment-related side effects by decreasing invasiveness and limiting toxicity. Owing to multiple advantageous properties of the porphyrin-HDL nanoparticle (PLP) as a PDT agent, including preferential accumulation in tumor, biodegradability and unprecedented photosensitizer packing, we evaluate PLP-mediated PDT as a minimally invasive, tumor-specific treatment for thyroid cancer. On both a biologically relevant human papillary thyroid cancer (K1) mouse model and an anatomically relevant rabbit squamous carcinoma (VX2)-implanted rabbit thyroid model, the intrinsic fluorescence of PLP enabled tracking of tumor preferential accumulation and guided PDT. This resulted in significant and specific apoptosis in tumor tissue, but not surrounding normal tissues including trachea and recurrent laryngeal nerve (RLN). A long-term survival study further demonstrated that PLP-PDT enabled complete ablation of tumor tissue while sparing both the normal thyroid tissue and RLN from damage, thus providing a safe, minimally invasive, and effective alternative to thyroidectomy for thyroid cancer therapies.

Free access

Fei Han, Wen-bin Liu, Jian-jun Li, Ming-qian Zhang, Jun-tang Yang, Xi Zhang, Xiang-lin Hao, Li Yin, Cheng-yi Mao, Xiao Jiang, Jia Cao, and Jin-yi Liu

Free access

Wei Zhang, Hang Zhang, and Xudong Zhao

Papillary thyroid carcinoma (PTC) is one of the most prevalent tumors in endocrine system. CircRNAs (circular RNAs) are widely known as critical regulators in tumorigenesis of papillary thyroid carcinoma (PTC). The present study focused on the functional investigation and potential molecular mechanism toward circ_0005273 in PTC progression. Gene Expression Omnibus datasets (GSE93522) and qRT-PCR (quantitative real-time PCR) analyses showed that circ_0005273 were upregulated in PTC tissues and cell lines. Moreover, circ_0005273 was located in the cytoplasm of PTC cells and suggested poor prognosis in PTC patients. In vivo and in vitro functional assays indicated that knockdown of circ_0005273 inhibited PTC tumor growth and progression, respectively. Mechanistically, miR-1183 was identified as functional target of circ_0005273, and circ_0005273 could directly bind to miR-1138 and relieve inhibition of SRY (sex-determining region Y)-box 2 (SOX2). Data from Cell Counting Kit-8, colony formation assays and transwell assays revealed that the oncogenic role of circ_0005273 on PTC progression dependent on miR-1183-mediated SOX2 expression. In conclusion, circ_0005273 functioned as a tumor promoter of PTC via circ_0005273/miR-1183/SOX2 axis, suggesting a novel biomarker and therapeutic target for PTC.

Free access

Anna Angelousi, Krystallenia I Alexandraki, George Kyriakopoulos, Marina Tsoli, Dimitrios Thomas, Gregory Kaltsas, and Ashley Grossman

Endocrine organs are metastatic targets for several primary cancers, either through direct extension from nearby tumour cells or dissemination via the venous, arterial and lymphatic routes. Although any endocrine tissue can be affected, most clinically relevant metastases involve the pituitary and adrenal glands with the commonest manifestations being diabetes insipidus and adrenal insufficiency respectively. The most common primary tumours metastasing to the adrenals include melanomas, breast and lung carcinomas, which may lead to adrenal insufficiency in the presence of bilateral adrenal involvement. Breast and lung cancers are the most common primaries metastasing to the pituitary, leading to pituitary dysfunction in approximately 30% of cases. The thyroid gland can be affected by renal, colorectal, lung and breast carcinomas, and melanomas, but has rarely been associated with thyroid dysfunction. Pancreatic metastasis can lead to exo-/endocrine insufficiency with renal carcinoma being the most common primary. Most parathyroid metastases originate from breast and lung carcinomas and melanoma. Breast and colorectal cancers are the most frequent ovarian metastases; prostate cancer commonly affects the testes. In the presence of endocrine deficiencies, glucocorticoid replacement for adrenal and pituitary involvement can be life saving. As most metastases to endocrine organs develop in the context of disseminated disease, surgical resection or other local therapies should only be considered to ameliorate symptoms and reduce tumour volume. Although few consensus statements can be made regarding the management of metastases to endocrine tissues because of the heterogeneity of the variable therapies, it is important that clinicians are aware of their presence in diagnosis.