Chemotherapy for recurrent cervical cancer

The effects of STA-9090 (Ganetespib) and venetoclax (ABT-199) combination on apoptotic pathways in human cervical cancer cells

Combined chemotherapy is recommended strategy as a first-line treatment method in patients with cervical cancer. Ganetespib (STA-9090) is a second-generation heat shock protein 90 (Hsp90) inhibitor that blocks the ATPase function of Hsp90 and inhibits the proper folding of oncogenic client proteins. Venetoclax (ABT-199) is an orally bioavailable Bcl-2 (B-cell lymphoma 2) inhibitor that stimulates apoptotic signaling pathways in cancer cells. This study evaluated the anticancer effects of STA-9090 combined with Venetoclax in the human cervical cancer cell line (HeLa). The human cervical cancer cells were treated with STA-9090, Venetoclax, and Sta-9090 plus Venetoclax for 48 h, and cell viability was measured using the XTT assay. The alteration of the Hsp90 protein expression level and the chaperone activity of HSP90 were detected by ELISA and luciferase aggregation assay, respectively. For the apoptotic process, qRT-PCR was applied to study Bcl-2-associated X protein (Bax), B-cell lymphoma 2 (Bcl-2), Bcl-2-like protein 1 (Bcl-xL ), Cytochrome c (Cyt-c), Caspase3 (Cas-3), and Caspase7 (Cas-7) expression levels after drug treatments. Also, a colorimetric Cas-3 activity assay was performed to detect the induction of the apoptosis process. Our results demonstrated that 8 nM of STA-9090 combined with 4 µM of Venetoclax synergistically inhibited cervical cancer cell proliferation more than STA-9090 or Venetoclax alone after 48 h of treatment. STA-9090 and Venetoclax combination decreased the protein expression level of Hsp90 and significantly inhibited chaperone activity of Hsp90. This combination stimulated apoptosis in cervical cancer cells by down-regulating of anti-apoptotic markers while inducing pro-apoptotic markers. Also, the STA-9090-Venetoclax combination increased Cas-3 activity in Hela cells. Collectively, these findings pointed out that the STA-9090-Venetoclax combination exhibited more activity than the individual drugs to stimulate toxicity and apoptosis in cervical cancer cells based on HSP90 inhibition.

Circular RNA circ_0004488 Increases Cervical Cancer Paclitaxel Resistance via the miR-136/MEX3C Signaling Pathway

Circular RNAs have been proven to play a pivotal role in cervical cancer development, progression, and treatment resistance. However, it is unclear how these RNAs influence chemoresistance in cervical cancer, particularly cancer stem cell (CSC)-like properties. In this study, we found that circRNA circ_0004488 was highly expressed in CSC-enriched subsets of cervical cancer cell lines. The expression of circ_0004488 was upregulated in cervical cancer cells that were resistant to paclitaxel. When circ_0004488 expression was high, the prognosis was poor. Specifically, we discovered that knocking down circ_0004488 greatly decreased the development of cervical cancer cells in vivo by decreasing cell proliferation, invasion, and sphere formation. By blocking cir_0004488, cervical cancer cells become more sensitive to paclitaxel. In cervical cancer cells, circ_0004488 acted as a microRNA-136 (miR-136) sponge, increasing the expression of MEX3C (a direct target gene of miR-136) using dual-luciferase reporter assays. Moreover, MEX3C downregulation significantly reduced cell proliferation, invasion, sphere formation, and paclitaxel resistance. In conclusion, circ_0004488 was shown to induce CSC-like features and paclitaxel resistance through the miR-136/MEX3C axis. Therefore, circ_0004488 might be a good therapeutic target for treating cervical cancer.

Identification of plasma proteins associated with oesophageal cancer chemotherapeutic treatment outcomes using SWATH-MS

Oesophageal adenocarcinoma (OAC) is an aggressive cancer with a five-year survival of <15%. Current chemotherapeutic strategies only benefit a minority (20-30%) of patients and there are no methods available to differentiate between responders and non-responders. We performed quantitative proteomics using Sequential Window Acquisition of all THeoretical fragment-ion spectra-Mass Spectrometry (SWATH-MS) on albumin/IgG-depleted and non-depleted plasma samples from 23 patients with locally advanced OAC prior to treatment. Individuals were grouped based on tumour regression (TRG) score (TRG1/2/3 vs TRG4/5) after chemotherapy, and differentially abundant proteins were compared. Protein depletion of highly abundant proteins led to the identification of around twice as many proteins. SWATH-MS revealed significant quantitative differences in the abundance of several proteins between the two groups. These included complement c1q subunit proteins, C1QA, C1QB and C1QC, which were of higher abundance in the low TRG group. Of those that were found to be of higher abundance in the high TRG group, glutathione S-transferase pi (GSTP1) exhibited the lowest p-value and highest classification accuracy and Cohen's kappa value. Concentrations of these proteins were further examined using ELISA-based assays. This study provides quantitative information relating to differences in the plasma proteome that underpin response to chemotherapeutic treatment in oesophageal cancers. SIGNIFICANCE: Oesophageal cancers, including oesophageal adenocarcinoma (OAC) and oesophageal gastric junction cancer (OGJ), are one of the leading causes of cancer mortality worldwide. Curative therapy consists of surgery, either alone or in combination with adjuvant or neoadjuvant chemotherapy or radiation, or combination chemoradiotherapy regimens. There are currently no clinico-pathological means of predicting which patients will benefit from chemotherapeutic treatments. There is therefore an urgent need to improve oesophageal cancer disease management and treatment strategies. This work compared proteomic differences in OAC patients who responded well to chemotherapy as compared to those who did not, using quantitative proteomics prior to treatment commencement. SWATH-MS analysis of plasma (with and without albumin/IgG-depletion) from OAC patients prior to chemotherapy was performed. This approach was adopted to determine whether depletion offered a significant improvement in peptide coverage. Resultant datasets demonstrated that depletion increased peptide coverage significantly. Additionally, there was good quantitative agreement between commonly observed peptides. Data analysis was performed by adopting both univariate as well as multivariate analysis strategies. Differentially abundant proteins were identified between treatment response groups based on tumour regression grade. Such proteins included complement C1q sub-components and GSTP1. This study provides a platform for further work, utilising larger sample sets across different treatment regimens for oesophageal cancer, that will aid the development of 'treatment response prediction assays' for stratification of OAC patients prior to chemotherapy.

Therapeutic Effects of Natural Products on Cervical Cancer: Based on Inflammatory Pathways

Inflammation is a protective response of the body to an irritant. When an inflammatory response occurs, immune cells are recruited to the injury, eliminating the irritation. The excessive inflammatory response can cause harm to the organism. Inflammation has been found to contribute to cervical cancer if there is a problem with the regulation of inflammatory response. Cervical cancer is one of the most common malignant tumors globally, and the incidence tends to be younger. The harm of cervical cancer cannot be ignored. The standard treatments for cervical cancer include surgery, radiotherapy and chemotherapy. However, the prognosis for this treatment is poor, so it is urgent to find a safer and more effective treatment. Natural products are considered excellent candidates for the treatment of cervical cancer. In this review, we first describe the mechanisms by which inflammation induces cervical cancer. Subsequently, we highlight natural products that can treat cervical cancer through inflammatory pathways. We also introduce natural products for the treatment of cervical cancer in clinical trials. Finally, methods to improve the anticancer properties of natural products were added, and the development status of natural products was discussed.

Degradation of DRAK1 by CUL3/SPOP E3 Ubiquitin ligase promotes tumor growth of paclitaxel-resistant cervical cancer cells

Despite favorable responses to initial chemotherapy, drug resistance is a major cause limiting chemotherapeutic efficacy in many advanced cancers. However, mechanisms that drive drug-specific resistance in chemotherapy for patients with advanced cancers are still unclear. Here, we report a unique role of death-associated protein kinase-related apoptosis-inducing kinase 1 (DRAK1) associated with paclitaxel resistance in cervical cancer cells. Interestingly, DRAK1 protein level was markedly decreased in paclitaxel-resistant cervical cancer cells without affecting its mRNA expression, which resulted in an increase in tumor necrosis factor receptor-associated factor 6 (TRAF6) expression, as well as an activation of TRAF6-mediated nuclear factor-kappa B (NF-κB) signaling cascade, thereby promoting tumor progression. DRAK1 depletion markedly increased the chemotherapeutic IC₅₀ values of paclitaxel in cervical cancer cells. Ectopic expression of DRAK1 inhibited growth of paclitaxel-resistant cervical cancer cells in vitro and in vivo. Furthermore, DRAK1 was markedly underexpressed in chemoresistant cervical cancer patient tissues compared with chemosensitive samples. We found that DRAK1 protein was destabilized through K48-linked polyubiquitination promoted by the Cullin scaffold protein 3 (CUL3) / speckle-type POZ (poxvirus and zinc finger protein) protein (SPOP) E3 ubiquitin ligase in paclitaxel-resistant cells. Collectively, these findings suggest that DRAK1 may serve as a potential predictive biomarker for overcoming paclitaxel resistance in cervical cancer.

Sorafenib Nanomicelles Effectively Shrink Tumors by Vaginal Administration for Preoperative Chemotherapy of Cervical Cancer

To investigate the potential of sorafenib (SF) in preoperative chemotherapy for cervical cancer to reduce tumor volume, sorafenib micelles (SF micelles) with good stability and high drug loading were designed. SF micelles were prepared by film hydration followed by the ultrasonic method. The results showed that the SF micelles were spherical with an average particle size of 67.18 ± 0.66 nm (PDI 0.17 ± 0.01), a considerable drug loading of 15.9 ± 0.46% (w/w%) and satisfactory stability in buffers containing plasma or not for at least 2 days. In vitro release showed that SF was gradually released from SF micelles and almost completely released on the third day. The results of in vitro cellular intake, cytotoxicity and proliferation of cervical cancer cell TC-1 showed that SF micelles were superior to sorafenib (Free SF). For intravaginal administration, SF micelles were dispersed in HPMC (SF micelles/HPMC), showed good viscosity sustained-release profiles in vitro and exhibited extended residence in intravaginal in vivo. Compared with SF micelles dispersed in N.S. (SF micelles/N.S.), SF micelles/HPMC significantly reduced tumor size with a tumor weight inhibition rate of 73%. The results suggested that SF micelles had good potential for preoperative tumor shrinkage and improving the quality life of patients.

Inhibition of the notch signaling pathway overcomes resistance of cervical cancer cells to paclitaxel through retardation of the epithelial-mesenchymal transition process

Use of paclitaxel as monotherapy or in combination with other therapeutic agents is a widely employed front-line chemotherapeutic strategy for cervical cancer. However, previous reports have shown that approximately 70% of the patients with cervical cancer develop resistance to paclitaxel. Epithelial-mesenchymal transition (EMT) contributes to the occurrence of chemoresistance in several types of cancer, including cervical cancer. Identification of the critical signaling pathway that regulates the EMT process may provide a novel strategy for avoiding or delaying the emergence of paclitaxel resistance during the treatment of cervical cancer. Herein, we established a paclitaxel-resistant cervical cancer cell line (HeLa-229PTR cells) by culturing parental HeLa-229 cells with increasing concentrations of paclitaxel. We observed elevated expression of Notch1 in HeLa-229PTR cells compared with their parental HeLa-229 cells, indicating its potential involvement in the EMT phenotype of the paclitaxel-resistant cells. Furthermore, silencing of the NOTCH1 gene, as well as treatment with a γ-secretase inhibitor (DAPT) partially reversed the EMT phenotype and significantly enhanced the sensitivity of HeLa-229PTR cells to paclitaxel. Moreover, we found that DAPT could significantly inhibit invasiveness, reduce colony formation activity, and promote apoptosis of HeLa-229PTR cells. Taken together, these results indicated that HeLa-229PTR cells develop the EMT phenotype partly through activation of Notch1 signaling. Thus, inhibition of Notch1 signaling can be a strategy for the reversal of the EMT phenotype and may increase the sensitivity of cervical cancer cells to treatment with paclitaxel.

MicroRNA-135a-induced formation of CD133+ subpopulation with cancer stem cell properties in cervical cancer

Cancer stem cells (CSCs) play significant roles in tumor initiation. MicroRNA-135a (miR-135a) induced the formation of a CD133+ subpopulation from a human papillomavirus-immortalized cervical epithelial cell line. Compared with the CD133- cells, the CD133+ cells expressed higher levels of miR-135a and OCT4, exhibited significantly higher tumorsphere forming capacity and the time required for tumorsphere formation was shortened in the second generation. Serum induction suppressed the expression of CD133, OCT4 and miR-135a, but increased expression of involucrin in the miR-135a-induced CD133+ cells. The miR-135a-induced CD133+ cells were tumorigenic in a limiting dilution approach in vivo. The cells expressed significantly higher level of active β-catenin and OCT4 than the CD133- counterpart. Wnt3a enhanced the expression of OCT4 and CD133 in cervical cancer cells but failed to enhance CD133 transcription in normal cervical cells. Wnt3a stimulation also increased tumorsphere size and self-renewal of miR-135a-induced CD133+ subpopulation. Wnt/β-catenin inhibition suppressed tumorsphere formation while Wnt3a partially nullified the inhibitory effect. Taken together, miR-135a induced the formation of a subpopulation of cells with CSC properties both in vitro and in vivo and the Wnt/β-catenin signaling pathway is essential to maintain its tumorigenicity.

PPI Modulators of E6 as Potential Targeted Therapeutics for Cervical Cancer: Progress and Challenges in Targeting E6

Advanced cervical cancer is primarily managed using cytotoxic therapies, despite evidence of limited efficacy and known toxicity. There is a current lack of alternative therapeutics to treat the disease more effectively. As such, there have been more research endeavors to develop targeted therapies directed at oncogenic host cellular targets over the past 4 decades, but thus far, only marginal gains in survival have been realized. The E6 oncoprotein, a protein of human papillomavirus origin that functionally inactivates various cellular antitumor proteins through protein–protein interactions (PPIs), represents an alternative target and intriguing opportunity to identify novel and potentially effective therapies to treat cervical cancer. Published research has reported a number of peptide and small-molecule modulators targeting the PPIs of E6 in various cell-based models. However, the reported compounds have rarely been well characterized in animal or human subjects. This indicates that while notable progress has been made in targeting E6, more extensive research is needed to accelerate the optimization of leads. In this review, we summarize the current knowledge and understanding of specific E6 PPI inhibition, the progress and challenges being faced, and potential approaches that can be utilized to identify novel and potent PPI inhibitors for cervical cancer treatment.

Inhibition of kinase IKKβ suppresses cellular abnormalities induced by the human papillomavirus oncoprotein HPV 18E6

Human papillomavirus (HPV) is the leading cause of cervical cancer and has been implicated in several other cancer types including vaginal, vulvar, penile, and oropharyngeal cancers. Despite the recent availability of a vaccine, there are still over 310,000 deaths each year worldwide. Current treatments for HPV-mediated cancers show limited efficacy, and would benefit from improved understanding of disease mechanisms. Recently, we developed a Drosophila ‘HPV 18 E6’ model that displayed loss of cellular morphology and polarity, junctional disorganization, and degradation of the major E6 target Magi; we further provided evidence that mechanisms underlying HPV E6-induced cellular abnormalities are conserved between humans and flies. Here, we report a functional genetic screen of the Drosophila kinome that identified IKK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\beta$$\end{document}β—a regulator of NF-κB—as an enhancer of E6-induced cellular defects. We demonstrate that inhibition of IKK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\beta$$\end{document}β reduces Magi degradation and that this effect correlates with hyperphosphorylation of E6. Further, the reduction in IKK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\beta$$\end{document}β suppressed the cellular transformation caused by the cooperative action of HPVE6 and the oncogenic Ras. Finally, we demonstrate that the interaction between IKK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\beta$$\end{document}β and E6 is conserved in human cells: inhibition of IKK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\beta$$\end{document}β blocked the growth of cervical cancer cells, suggesting that IKK\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\beta$$\end{document}β may serve as a novel therapeutic target for HPV-mediated cancers.

Inhibiting Importin 4-mediated nuclear import of CEBPD enhances chemosensitivity by repression of PRKDC-driven DNA damage repair in cervical cancer

Cervical cancer (CC) remains highest in the mortality of female reproductive system cancers, while cisplatin (CDDP) resistance is the one of main reasons for the lethality. Preceding evidence has supported that karyopherins are associated with chemoresistance. In this study, we simultaneously compared CDDP-incomplete responders with CDDP-complete responders of CC patients and CDDP‐insensitive CC cell lines with CDDP‐sensitive group. We finally identified that DNA-PKcs (PRKDC) was related to CDDP sensitivity after overlapping in CC sample tissues and CC cell lines. Further functional assay revealed that targeting PRKDC by shRNA and NU7026 (specific PRKDC inhibitor) could enhance CDDP sensitivity in vitro and in vivo, which was mediated by impairing DNA damage repair pathway in CC. Mechanistically, we found that PRKDC was transcriptionally upregulated by CCAAT/enhancer-binding protein delta (CEBPD), while intriguingly, CDDP treatment strengthened the transcriptional activity of CEBPD to PRKDC. We further disclosed that Importin 4 (IPO4) augmented the nuclear translocation of CEBPD through nuclear localization signals (NLS) to activate PRKDC-mediated DNA damage repair in response to CDDP. Moreover, we demonstrated that IPO4 and CEBPD knockdown improved CDDP-induced cytotoxicity in vitro and in vivo. Together, we shed the novel insight into the role of IPO4 in chemosensitivity and provide a clinical translational potential to enhance CC chemosensitivity since the IPO4-CEBPD-PRKDC axis is actionable via NU7026 (PRKDC inhibitor) or targeting IPO4 in combination with CDDP.

An Oral Small Molecule VEGFR2 Inhibitor, Apatinib, in Patients with Recurrent or Refractory Cervical Cancer: A Real World Study

To evaluate the efficacy and safety of apatinib, an oral antiangiogenic drug, in patients with recurrent or refractory cervical cancer as salvage treatment, we retrospectively analyzed the medical records of recurrent or refractory cervical cancer patients admitted to the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Hunan Cancer Hospital, from October 1, 2016, to December 31, 2017. Patients who progressed within 6 months after the last treatment were given apatinib orally at a dose of 250 mg daily until disease progression or unacceptable toxicity. Twenty-nine patients were enrolled in our retrospective study. Up to February 1, 2019, the median follow-up time was 18 months. The median progression-free survival was 128 days (95% confidence interval (CI): 20–540 days), and the median overall survival was 9 months (95% CI: 4–23 months). The longest period of apatinib administration was 540 days. No complete response was observed, 5 (17.2%) patients achieved partial response, and 11 (37.9%) achieved stable disease. The objective response rate and disease control rate were 17.2% and 55.1%, respectively. The most common adverse events were hypertension (G1, 65.5%, 19/29), mucositis (G1, 55.2%, 16/29), hand-foot syndrome (G1-2, 44.8%, 13/29), and proteinuria (G1-2, 20.7%, 6/29). Grade 3 proteinuria occurred in only one patient (3.4%, 1/29). Apatinib single-agent use might be an effective and tolerable choice as salvage therapy for patients with recurrent or refractory cervical cancer.

Expression of the Long Noncoding RNA DINO in Human Papillomavirus-Positive Cervical Cancer Cells Reactivates the Dormant TP53 Tumor Suppressor through ATM/CHK2 Signaling

Functional restoration of the TP53 tumor suppressor holds great promise for anticancer therapy. Current strategies are focused on modulating TP53 regulatory proteins. Long noncoding RNAs (lncRNAs) have emerged as important regulators of TP53 as well as modulators of downstream tumor-suppressive transcriptional responses. Unlike many other cancer types, human papillomavirus (HPV)-positive cancer cells retain wild-type TP53 that is rendered dysfunctional by the viral E6 protein. We show that acute expression of the damage-induced long noncoding RNA, DINO, a known TP53 transcriptional target and functional modulator, causes TP53 reactivation in HPV-positive cervical cancer cells. This causes increased vulnerability to standard chemotherapeutics as well as biguanide compounds that cause metabolic stress. Hence, strategies that target DINO may be useful for restoring TP53 tumor suppressor activity in HPV-positive cancers and other tumor types that retain wild-type TP53.

Tumor cells overcome the cytostatic and cytotoxic restraints of TP53 tumor suppressor signaling through a variety of mechanisms. High-risk human papillomavirus (HPV)-positive tumor cells retain wild-type TP53 because the HPV E6/UBE3A ubiquitin ligase complex targets TP53 for proteasomal degradation. While restoration of TP53 in tumor cells holds great promise for cancer therapy, attempts to functionally restore the dormant TP53 tumor suppressor in HPV-positive cancer cells by inhibiting the HPV E6/UBE3A ubiquitin ligase complex have not yet been successful. The damage-induced long noncoding RNA, DINO (DINOL), is a TP53 transcriptional target that has been reported to bind to and stabilize TP53, thereby amplifying TP53 signaling. We show that HPV-positive cervical carcinoma cells contain low levels of DINO because of HPV E6/UBE3A-mediated TP53 degradation. Acute DINO expression overrides HPV16 E6/UBE3A-mediated TP53 degradation, causing TP53 stabilization and increased expression of TP53 transcriptional target genes. This causes a marked sensitization to chemotherapy agents and renders cells vulnerable to metabolic stress. Acute DINO expression in HPV-positive cervical cancer cells induces hallmarks of DNA damage response signaling, and TP53 activation involves ATM/CHK2 signaling. DINO upregulation in response to DNA damage is independent of ATM/CHK2 and can occur in cancer cells that express mutant TP53.

Potential Role of DEC1 in Cervical Cancer Cells Involving Overexpression and Apoptosis

Basic helix-loop-helix (BHLH) transcription factors differentiated embryonic chondrocyte gene 1 (DEC1) and gene 2 (DEC2) regulate circadian rhythms, apoptosis, epithelial mesenchymal transition (EMT), invasions and metastases in various kinds of cancer. The stem cell markers SOX2 and c-MYC are involved in the regulation of apoptosis and poor prognosis. In cervical cancer, however, their roles are not well elucidated yet. To determine the function of these genes in human cervical cancer, we examined the expression of DEC1, DEC2, SOX2 and c-MYC in human cervical cancer tissues. In immunohistochemistry, they were strongly expressed in cancer cells compared with in non-cancerous cells. Notably, the strong rate of DEC1 and SOX2 expressions were over 80% among 20 cases. We further examined the roles of DEC1 and DEC2 in apoptosis. Human cervical cancer HeLa and SiHa cells were treated with cisplatin-HeLa cells were sensitive to apoptosis, but SiHa cells were resistant. DEC1 expression decreased in the cisplatin-treated HeLa cells, but had little effect on SiHa cells. Combination treatment of DEC1 overexpression and cisplatin inhibited apoptosis and affected SOX2 and c-MYC expressions in HeLa cells. Meanwhile, DEC2 overexpression had little effect on apoptosis and on SOX2 and c-MYC expressions. We conclude that DEC1 has anti-apoptotic effects and regulates SOX2 and c-MYC expressions on apoptosis.

Pulmonary recurrence after radical hysterectomy for uterine cervical carcinoma

Pulmonary spread from carcinoma of the uterine cervix, though uncommon, has been reported in 2.2-9.1% of all cervical cancers. The aim of this study was to evaluate the surgical, clinical, pathological factors and clinical outcomes of cervical cancer patients with pulmonary recurrence (PR).This study included 17 cervical cancer patients with PR after radical hysterectomy. The entire cohort consisted of 413 patients whose surgeries (type III radical hysterectomy + pelvic ± para-aortic lymphadenectomy) had been performed in our Gynaecologic Oncology Clinic between 1993 and 2018. Tumour size, lymph node metastasis and receiving adjuvant therapy were found to be effective for PR on univariate analyses in the main cohort (p = .042, p < .001 and p = .001, respectively). Therefore, performing adjuvant therapy to reduce the PR must be assessed properly with the information of lymph node status and tumour size obtained from the final pathology reports.Impact StatementWhat is already known on this subject? Pulmonary spread from carcinoma of the uterine cervix has been reported in 2.2-9.1% of all cervical cancers. Data related to clinico-pathological features of patients with pulmonary recurrence (PR) is limited. Diagnosis of a PR is considered to worsen the prognosis.What do the results of this study add? Tumour size, lymph node metastasis and receiving adjuvant therapy were found to be effective for PR on univariate analyses.What are the implications of these findings for clinical practice and/or further research? Performing adjuvant therapy to reduce the PR must be assessed properly with the information of lymph node status and tumour size obtained from the final pathology reports in patients with uterine cervical carcinoma.

Genes Involved in the Transcriptional Regulation of Pluripotency Are Expressed in Malignant Tumors of the Uterine Cervix and Can Induce Tumorigenic Capacity in a Nontumorigenic Cell Line

Transcription factors OCT4, SOX2, KLF4, C-MYC, and NANOG (OSKM-N) regulate pluripotency and stemness, and their ectopic expression reprograms human and murine fibroblasts that constitute the key of regenerative medicine. To determine their contribution to cell transformation, we analyzed the gene expression profiles of these transcription factors in cervical cancer samples and found that they are preferentially expressed in the tumor component. Also, cancer stem cell-enriched cultures grown as sphere cultures showed overexpression of OSKM-N genes. Importantly, we observed that lentiviral-mediated transduction of these factors confers, to a nontumorigenic immortalized human cell line, properties of cancer stem cells as the ability to form tumors in a mouse model. When we performed a meta-analysis using microarray data from cervical cancer biopsies and normal tissues, we found that the expression of OSKM-N and some target genes allowed separating tumor and normal tissues between samples, which enhanced the importance of OSKM-N in the tumorigenesis. Finally, we analyzed and compared both transcript and protein expression profiles of these factors within a cohort of patients with cervical cancer. To our knowledge, this is the first time that the expression of OSKM-N is described to induce one of the main characteristics of the cancer stem cell, the tumorigenicity. And, more importantly, its exogenous expression in a nontumorigenic cell line is sufficient to induce a tumorigenic phenotype; furthermore, the differential expression of this transcription factor distinguishes tumor tissue and normal tissue in cervical samples.

Anti-Cancer Activity of a 5-Aminopyrazole Derivative Lead Compound (BC-7) and Potential Synergistic Cytotoxicity with Cisplatin against Human Cervical Cancer Cells

The use of some very well-known chemotherapeutic agents, such as cisplatin, is limited by toxicity in normal tissues and the development of drug resistance. In order to address drug resistance and the side-effects of anti-cancer agents, recent research has focused on finding novel combinations of anti-cancer agents with non-overlapping mechanisms of action. The cytotoxic effect of the synthetic 5-aminopyrazole derivative N-[[3-(4-bromophenyl)-1H-pyrazol-5-yl]-carbamothioyl]-4-chloro-benzamide (BC-7) was evaluated by the bis-Benzamide H 33342 trihydrochloride/propidium iodide (Hoechst 33342/PI) dual staining method against HeLa, MeWo, HepG2, Vero, and MRHF cell lines. Quantitative fluorescence image analysis was used for the elucidation of mechanism of action and synergism with cisplatin in HeLa cells. BC-7 displayed selective cytotoxicity towards HeLa cells (IC₅₀ 65.58 ± 8.40 μM) and induced apoptosis in a mitochondrial- and caspase dependent manner. This was most likely preceded by cell cycle arrest in the early M phase and the onset of mitotic catastrophe. BC-7 increased the cytotoxic effect of cisplatin in a synergistic manner with combination index (CI) values less than 0.9 accompanied by highly favourable dose reduction indices. Therefore, the results obtained support the implication that BC-7 has potential anti-cancer properties and that combinations of BC-7 with cisplatin should be further investigated for potential clinical applications.

LncRNA GAS5 regulates the proliferation, migration, invasion and apoptosis of brain glioma cells through targeting GSTM3 expression. The effect of LncRNA GAS5 on glioma cells

INTRODUCTION

To investigate the effects of lncRNA GAS5 on the proliferation, migration, invasion and apoptosis of brain glioma cells.

METHODS

The expression levels of lncRNA GAS5 and GSTM3 in normal glial cells (HEB) and glioma cells (U251 and U87) were detected by RT-qPCR and western blot, respectively. Glioma cells were transfected with ctrl vector, pcDNA-GAS5, siRNA ctrl (siNC) or GSTM3 siRNA and the effects of lncRNA GAS5 and GSTM3 on the proliferation, migration, invasion and apoptosis of glioma cells were detected by CCK-8 assay, transwell assay and Caspase 3/7 activity assay, respectively.

RESULTS

The expression of lncRNA GAS5 was significantly decreased in glioma cell lines U251 and U87 compared with normal glial cells HEB (p < 0.01). In addition, overexpression of lncRNA GAS5 inhibited the proliferation, migration and invasion of U251 and U87 cells, and promoted cell apoptosis as demonstrated by the increased activity of Caspase 3/7. Furthermore, GSTM3 was predicted as a target gene of lncRNA GAS5 by bioinformatics analysis and its expression was increased in glioma cells compared with the normal cells as indicated by western blotting and RT-qPCR experimental results. Silencing of GSTM3 with GSTM3 siRNA decreased the proliferation, migration and invasion but increased the apoptosis of glioma cell lines U251 and U87, which was similar to that the effect lncRNA GAS5 over-expression.

CONCLUSION

lncRNA GAS5 can effectively inhibit the proliferation, migration and invasion of glioma cells and promote cell apoptosis through targeting GSTM3 expression.

Clinical outcomes after isolated pelvic failure in cervical cancer patients treated with definitive radiation

PURPOSE

To describe clinical outcomes in patients with isolated pelvic failures after definitive radiation treatment for cervical cancer.

METHODS AND MATERIALS

Cervical cancer patients with isolated pelvic failure after definitive radiation with brachytherapy boost were identified in a tertiary academic center database from 1997 to 2016. All patients received an FDG-PET scan prior to their initial treatment and at the time of their first recurrence. Isolated failures in the cervix or pelvic nodes were biopsy-proven. Distant failure and overall survival (OS) were censored outcomes.

RESULTS

Isolated pelvic failure was detected in 67(11%) out of 607 consecutive patients treated with external beam pelvic radiation and brachytherapy boost. The median time to isolated pelvic recurrence was 9 months (range 3-198). Median follow-up time for patients alive after isolated pelvic recurrence was 40 months (range 0.6-183). Of these 67 patients, 28(42%) received salvage surgery, 17(25%) received chemotherapy alone, and 22(33%) received neither surgery nor chemotherapy. The median time to distant failure after isolated pelvic failure was 20 months (95% CI 3-37), with no significant difference between patients treated surgically vs. non-surgically. FDG-avid pelvic and para-aortic nodes at initial presentation were associated with worse distant control after isolated pelvic failure (HR = 3.4, 95% CI 1.0-12). Median OS for patients treated with surgery, chemotherapy alone, and neither surgery nor chemotherapy was 29 months (95% CI 16-41), 12 months (95% CI 3-21), and 3 months (95% CI 1-5), respectively.

CONCLUSIONS

Patients who have pelvic and para-aortic nodal disease at initial presentation are at higher risk of failing distantly after isolated pelvic failure, which should be considered when counseling patients on aggressive surgical salvage. Surgical salvage was associated with prolonged survival after isolated pelvic failure.

Cancer Stem Cells from Tumor Cell Lines Activate the DNA Damage Response Pathway after Ionizing Radiation More Efficiently Than Noncancer Stem Cells

Recently, a subpopulation of tumor cells, called cancer stem cells (CSC), has been characterized, and these have emerged as a major topic in cancer research. CSC are proposed to repair DNA damage more efficiently than the rest of tumor cells, resisting chemotherapy or radiotherapy and causing clinical recurrence and metastasis. We aimed to determine the molecular basis of radioresistance and first compared the response to ionizing radiation (IR) between cancer stem cell-enriched cultures grown as spheres and conventional tumor cell line cultures grown as monolayer, from HeLa and MCF-7 cancer cell lines. To verify that our sphere cultures were enriched in CSC, we evaluated the double staining of CD49f and ALDH activity for HeLa cells by flow cytometry. We then evaluated whether differences could exist in sensor elements in the DNA damage response pathway among these cultures. We found that CSC cultures showed less sensitivity to radiation than conventional tumor cell line cultures. We observed a higher baseline expression of activated response sensor proteins of DNA damage, such as ATM, H2A.X, and PARP1, in untreated CSC cultures. These findings provide the first evidence, to our knowledge, that DNA damage response sensor proteins are present and preferentially activated in CSC, as opposed to the bulk of cells in monolayer cultures. Likewise, they provide the basis for biological differences in response to IR between CSC and other tumor cell populations. Understanding the DNA damage response pathway may provide therapeutic targets to sensitize CSC to cytotoxic therapies to improve current cancer treatments.

HOXD-AS1 Exerts Oncogenic Functions and Promotes Chemoresistance in Cisplatin-Resistant Cervical Cancer Cells

Long noncoding RNAs (lncRNAs) are important regulators in various human diseases. The lncRNA HOXD-AS1 is a tumor promoter in ovarian cancer, glioma, and lung cancer, but the specific effects of HOXD-AS1 on cervical cancer (CC) chemoresistance remain unclear. Here, the level of HOXD-AS1 in nonmalignant and CC tissues as well as in CC cells and cisplatin-resistant CC cells was determined. qRT-PCR indicated that HOXD-AS1 was overexpressed in CC tissues and cisplatin-resistant CC cells. Loss-of-function assays showed that downregulation of HOXD-AS1 expression suppressed chemoresistance of cisplatin-resistant CC cells. HOXD-AS1 targeted miR-130a-3p, and in gain-of-function assays miR-130a-3p could reverse cisplatin resistance of CC cells. miR-130a-3p in turn targeted zinc finger E-box homeobox 1 (ZEB1). These results collectively show that HOXD-AS1 can act as a competing endogenous RNA to upregulate ZEB1 expression via miR-130a-3p. The effects of the HOXD-AS1-miR-130a-3p-ZEB1 axis on cisplatin resistance of cisplatin-resistant CC cells were supported by rescue assay results. In summary, HOXD-AS1 enhanced chemoresistance of cisplatin-resistant CC cells by modulating miR-130a-3p/ZEB1 axis expression.

GSTM3 and GSTP1: novel players driving tumor progression in cervical cancer

The molecular processes and proteomic markers leading to tumor progression (TP) in cervical cancer (CC) are either unknown or only partially understood. TP affects metabolic and regulatory mechanisms that can be identified as proteomic changes. To identify which proteins are differentially expressed and to understand the mechanisms of cancer progression, we analyzed the dynamics of the tumor proteome in CC cell lines. This analysis revealed two proteins that are up-regulated during TP, GSTM3 and GSTP1. These proteins are involved in cell maintenance, cell survival and the cellular stress response via the NF-κB and MAP kinase pathways during TP. Furthermore, GSTM3 and GSTP1 knockdown showed that evasion of apoptosis was affected, and tumor proliferation was significantly reduced. Our data indicate the critical role of GST proteins in the regulation and progression of cervical cancer cells. Hence, we suggest GSTM3 and GSTP1 as novel biomarkers and potential therapeutic targets for treating cervical cancer.

SIGNIFICANCE

CC is particularly hazardous in the advanced stages, and there are few therapeutic strategies specifically targeting these stages. We performed analyses on CC tumor proteome dynamics and identified GSTM3 and GSTP1 as novel potential therapeutic targets. Knockdown of these proteins showed that they are involved in cell survival, cell proliferation and cellular evasion of apoptosis.

NHERF1 Enhances Cisplatin Sensitivity in Human Cervical Cancer Cells

Cervical cancer is one of the most common female malignancies, and cisplatin-based chemotherapy is routinely utilized in locally advanced cervical cancer patients. However, resistance has been the major limitation. In this study, we found that Na⁺/H⁺ Exchanger Regulatory Factor 1 (NHERF1) was downregulated in cisplatin-resistant cells. Analysis based on a cervical cancer dataset from The Cancer Genome Atlas (TCGA) showed association of NHERF1 expression with disease-free survival of patients received cisplatin treatment. NHERF1 overexpression inhibited proliferation and enhanced apoptosis in cisplatin-resistant HeLa cells, whereas NHERF1 knockdown had inverse effects. While parental HeLa cells were more resistant to cisplatin after NHERF1 knockdown, NHERF1 overexpression in CaSki cells promoted cisplatin sensitivity. Overexpression and knockdown studies also showed that NHERF1 significantly inhibited AKT and extracellular signal–regulated kinase (ERK) signaling pathways in cisplatin-resistant cells. Taken together, our results provide the first evidence that NHERF1 can sensitize cisplatin-refractory cervical cancer cells. This study may help to increase understanding of the molecular mechanisms underlying cisplatin resistance in tumors.

Development and evaluation of topotecan loaded solid lipid nanoparticles: A study in cervical cancer cell lines

The study aims at statistical development of solid lipid nanoparticles (SLNs) loaded with topotecan hydrochloride for avoiding the drawbacks of conventional drug therapies used in cervical cancer. Twenty SLN batches were prepared using organic solvent evaporation method to provide response surface curves. Thereafter, optimized SLNs were obtained using numeric method based on desirability functions providing maximum drug loading and appropriate particle size. Physical characterization of optimized TPH loaded SLNs was performed in terms of particle size, zeta potential, transmission and scanning electron microscopic evaluation. Cytotoxicity studies were performed against cervical cancer cell lines, including cervical squamous cell carcinoma cell line (HeLa) and human squamous cell carcinoma cell line (SiHa). Also, Swiss mouse embryo fibroblast cells (3T3-L1) and African green monkey kidney epithelial (Vero) cells were used to evaluate biocompatibility in normal cells. As pronounced from the results, optimized SLNs may provide an attractive alternative to conventional cervical cancer drug products.

STAT3 activity regulates sensitivity to tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis in cervical cancer cells

In cervical cancer, p53-induced apoptosis is abrogated by human papilloma virus (HPV)-derived oncoprotein E6. Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) provides tumor-specific apoptosis in various cancers, including cervical cancer, the sensitivity differs depending on the cell lines. Signal transducer and activator of transcription 3 (STAT3) is a hub molecule that shifts the cellular fate to apoptosis or survival in response to cellular stresses. However, the contribution of STAT3 activity to TRAIL-induced apoptosis in cervical cancer remains unknown. We examined the TRAIL sensitivity in cervical cancer cells, using TRAIL-resistant (SiHa) and -sensitive (CaSki) cervical cancer cell lines and focused on STAT3 function involving the apoptotic pathway. STAT3 was inactivated by TRAIL stimulation in the CaSki cell line, but not in the SiHa cell line. We then inhibited STAT3 expression in the SiHa cell line using siRNA against STAT3 and suppressed STAT3 activity using a STAT3 inhibitor; both these treatments sensitized TRAIL-induced apoptosis in the SiHa cell line. Furthermore, the SiHa cells were exposed to tunicamycin (TM), an endoplasmic reticulum (ER) stress inducer that inactivates STAT3, with or without TRAIL. Accompanied by STAT3 inactivation, TM pretreatment significantly enhanced TRAIL-induced apoptosis. We therefore concluded that TRAIL-induced apoptosis was regulated by STAT3 in response to TRAIL stimulation. Our results also suggest that STAT3 inhibition increases the sensitivity of malignancies, particularly HPV-related cancer, to TRAIL-based therapy.

Sphingosine kinase 1 is a reliable prognostic factor and a novel therapeutic target for uterine cervical cancer

Sphingosine kinase 1 (SPHK1), an oncogenic kinase, has previously been found to be upregulated in various types of human malignancy and to play a crucial role in tumor development and progression. Although SPHK1 has gained increasing prominence as an important enzyme in cancer biology, its potential as a predictive biomarker and a therapeutic target in cervical cancer remains unknown. SPHK1 expression was examined in 287 formalin-fixed, paraffin-embedded cervical cancer tissues using immunohistochemistry, and its clinical implications and prognostic significance were analyzed. Cervical cancer cell lines including HeLa and SiHa were treated with the SPHK inhibitors SKI-II or FTY720, and effects on cell survival, apoptosis, angiogenesis, and invasion were examined. Moreover, the effects of FTY720 on tumor growth were evaluated using a patient-derived xenograft (PDX) model of cervical cancer. Immunohistochemical analysis revealed that expression of SPHK1 was significantly increased in cervical cancer compared with normal tissues. SPHK1 expression was significantly associated with tumor size, invasion depth, FIGO stage, lymph node metastasis, and lymphovascular invasion. Patients with high SPHK1 expression had lower overall survival and recurrence-free survival rates than those with low expression. Treatment with SPHK inhibitors significantly reduced viability and increased apoptosis in cervical cancer cells. Furthermore, FTY720 significantly decreased in vivo tumor weight in the PDX model of cervical cancer. We provide the first convincing evidence that SPHK1 is involved in tumor development and progression of cervical cancer. Our data suggest that SPHK1 might be a potential prognostic marker and therapeutic target for the treatment of cervical cancer.

Cervical Cancer Stem Cells Selectively Overexpress HPV Oncoprotein E6 that Controls Stemness and Self-Renewal through Upregulation of HES1

PURPOSE

Perturbation of keratinocyte differentiation by E6/E7 oncoproteins of high-risk human papillomaviruses that drive oncogenic transformation of cells in squamocolumnar junction of the uterine cervix may confer "stem-cell like" characteristics. However, the crosstalk between E6/E7 and stem cell signaling during cervical carcinogenesis is not well understood. We therefore examined the role of viral oncoproteins in stem cell signaling and maintenance of stemness in cervical cancer.

EXPERIMENTAL DESIGN

Isolation and enrichment of cervical cancer stem-like cells (CaCxSLCs) was done from cervical primary tumors and cancer cell lines by novel sequential gating using a set of functional and phenotypic markers (ABCG2, CD49f, CD71, CD133) in defined conditioned media for assessing sphere formation and expression of self-renewal and stemness markers by FACS, confocal microscopy, and qRT-PCR. Differential expression level and DNA-binding activity of Notch1 and its downstream targets in CaCxSLCs as well as silencing of HPVE6/Hes1 by siRNA was evaluated by gel retardation assay, FACS, immunoblotting, and qRT-PCR followed by in silico and in vivo xenograft analysis.

RESULTS

CaCxSLCs showed spheroid-forming ability, expressed self-renewal and stemness markers Oct4, Sox2, Nanog, Lrig1, and CD133, and selectively overexpressed E6 and HES1 transcripts in both cervical primary tumors and cancer cell lines. The enriched CaCxSLCs were highly tumorigenic and did recapitulate primary tumor histology in nude mice. siRNA silencing of HPVE6 or Hes1 abolished sphere formation, downregulated AP-1-STAT3 signaling, and induced redifferentiation.

CONCLUSIONS

Our findings suggest the possible mechanism by which HPVE6 potentially regulate and maintain stem-like cancer cells through Hes1. Clin Cancer Res; 22(16); 4170-84. ©2016 AACR.

CIP2A is associated with multidrug resistance in cervical adenocarcinoma by a P-glycoprotein pathway

Cancerous inhibitor of protein phosphatase 2A (CIP2A) is a recently identified oncoprotein. Here, we investigated its role in the formation of multidrug resistance (MDR) of cervical adenocarcinoma in vitro and in vivo. MTT assay showed that knockdown of CIP2A expression increased the drug sensitivity of HeLa and Dox-resistant HeLa cells (HeLa-Dox) to doxorubicin, cisplatin, and paclitaxel significantly, while overexpression of CIP2A decreased the sensitivity of HeLa cells to chemo-drugs dramatically. When treated with different chemotherapeutics, CIP2A and P-glycoprotein (P-gp) protein levels were increased in HeLa cells simultaneously. In accordance with it, knockdown or overexpression of CIP2A expression inhibited or increased the P-gp expression in the transcription level separately. The effects of CIP2A on P-gp expression was achieved partly through its regulation on the transcription factor E2F1. Moreover, the interference of CIP2A could decrease the P-gp protein activity elucidated by Rhodamine 123 (Rh123) efflux assay in HeLa and HeLa/Dox cells. In the in vivo level, confocal microscopy data demonstrated the strong co-localization of CIP2A and P-gp protein in HeLa cells, and CIP2A protein expression was significantly associated with that of P-gp in cervical adenocarcinoma tissues. Thus, CIP2A is involved in regulating multidrug resistance of cervical adenocarcinoma upon chemotherapy by enhancing P-gp expression through E2F1. CIP2A may be an attractive target in anticancer strategies to improve the effect of chemotherapy in cervical adenocarcinoma.

Inhibition of Phosphatidylcholine-Specific Phospholipase C Interferes with Proliferation and Survival of Tumor Initiating Cells in Squamous Cell Carcinoma

Purpose

The role of phosphatidylcholine-specific phospholipase C (PC-PLC), the enzyme involved in cell differentiation and proliferation, has not yet been explored in tumor initiating cells (TICs). We investigated PC-PLC expression and effects of PC-PLC inhibition in two adherent (AD) squamous carcinoma cell lines (A431 and CaSki), with different proliferative and stemness potential, and in TIC-enriched floating spheres (SPH) originated from them.

Results

Compared with immortalized non-tumoral keratinocytes (HaCaT) A431-AD cells showed 2.5-fold higher PC-PLC activity, nuclear localization of a 66-kDa PC-PLC isoform, but a similar distribution of the enzyme on plasma membrane and in cytoplasmic compartments. Compared with A431-AD, A431-SPH cells showed about 2.8-fold lower PC-PLC protein and activity levels, but similar nuclear content. Exposure of adherent cells to the PC-PLC inhibitor D609 (48h) induced a 50% reduction of cell proliferation at doses comprised between 33 and 50 μg/ml, without inducing any relevant cytotoxic effect (cell viability 95±5%). In A431-SPH and CaSki-SPH D609 induced both cytostatic and cytotoxic effects at about 20 to 30-fold lower doses (IC50 ranging between 1.2 and 1.6 μg/ml). Furthermore, D609 treatment of A431-AD and CaSki-AD cells affected the sphere-forming efficiency, which dropped in both cells, and induced down-modulation of stem-related markers mRNA levels (Oct4, Nestin, Nanog and ALDH1 in A431; Nestin and ALDH1 in CaSki cells).

Conclusions

These data suggest that the inhibition of PC-PLC activity may represent a new therapeutic approach to selectively target the most aggressive and tumor promoting sub-population of floating spheres originated from squamous cancer cells possessing different proliferative and stemness potential.

Effects of doxorubicin mediated by gold nanoparticles and resveratrol in two human cervical tumor cell lines

Green synthesis of gold nanoparticles capped with resveratrol (GNPs) and their physical and chemical characterization by UV-vis spectra, FTIR, DLS, XRD, TEM and AFM are reported. The GNPs are highly stable, with average diameter of about 20 nm. Then, supramolecular nanoassemblies of GNPs and doxorubicin (Dox), Dox-GNPs complexes, were prepared and morphologically characterized. The stability of these Dox nanocomplexes is high in phosphate buffer saline as estimated by UV-vis spectra, TEM and AFM analysis. Effects of resveratrol (Resv), Resv-Dox mixtures, GNPs and Dox-GNPs complexes on HeLa and CaSki cells, after 24h drug incubation, were assessed using MTT cell viability assay. Results showed strong anticancer activity for Resv-Dox mixtures and Dox-GNPs complexes in the two human cervical carcinoma cell lines. Clearly, both Resv and GNPs can mediate the anticancer activity of Dox at its very low concentration of 0.1 μg/mL, reaching the cytotoxicity of Dox alone, at its concentration up to 20 times higher. Cytotoxic effects of Resv-Dox mixtures and Dox-GNPs complexes have been found for the first time in HeLa and CaSki cells. Furthermore, the apoptosis induction in HeLa and CaSki cells was evidenced for Resv-Dox mixtures and Dox-GNPs complexes by flow cytometry using Annexin V-FITC/propidium iodide cellular staining. For CaSki cells, the apoptosis was also demonstrated, mainly for the treatment with Dox-GNPs complexes, by MTT formazan cellular staining visualized in phase contrast microscopy. Our results provide strong evidence that novel drug delivery vehicles developed on Dox-GNPs nanocomplexes and Resv could have wide applications in cancer diagnosis and treatment.

The enhanced inhibitory effect of different antitumor agents in self-microemulsifying drug delivery systems on human cervical cancer HeLa cells

The aim of this study was to develop topical self-microemulsifying drug delivery systems (SMEDDS) containing antitumor agents (bleomycin, cisplatin and ifosfamide) and to investigate their inhibitory potential in SMEDDS on human cervical cancer HeLa cells. The physicochemical properties of cytostatic drug loaded SMEDDS were characterized. The cytotoxicity of main components of SMEDDS was also investigated. Their IC₅₀ values were determined. HeLa cells were treated by different concentrations of cisplatin, bleomycin and ifosfamide alone and in various SMEDDS. The inhibitory effect on cell growth was analyzed by MTT cell viability assay. Inflammation is a driving force that accelerates cancer development. The inhibitory effect of these antitumor agents has also been tested on HeLa cells in the presence of inflammatory mediators (IL-1-β, TNF-α) as an in vitro model of inflamed human cervix. Significant differences in the cytotoxicity of cytostatic drugs alone and in SMEDDS have been found in a concentration-dependent manner. The self-micro emulsifying system may potentiate the effectiveness of bleomycin, cisplatin and ifosfamide topically. The effect of SMEDDS containing antitumor agents was decreased significantly in the presence of inflammatory mediators. According to our experiments, the optimal SMEDDS formulation is 1:1:2:6:2 ratios of Isopropyl myristate, Capryol 90, Kolliphor RH 40, Cremophor RH40, Transcutol HP and Labrasol. It can be concluded that SMEDDS may increase the inhibitory effect of bleomycin, ifosfamide and cisplatin on human cervical cancer HeLa cells. Inflammation on HeLa cells hinders the effectiveness of SMEDDS containing antitumor agents. Our results might ensure useful data for development of optimal antitumor formulations.

Enhanced anti-tumor efficacy of aspirin combined with triptolide in cervical cancer cells

BACKGROUND

The non-steroidal anti-inflammatory drug (NSAID) aspirin (acetylsalicylic acid) is an inhibitor of cyclooxygenase enzymes. Recent studies have shown that aspirin could be used as an anti-tumor drug. Triptolide, the major compound extracted from the Chinese herb Tripteryglum wilfordii Hook.f, has now been shown that it can inhibit tumor growth. The aim of this study was to analyze the anti-tumor efficiency of aspirin and triptolide in cervical cancer cells.

METHODS

Viability of cervical cancer cell lines was assessed by the MTT method at various concentrations of aspirin and triptolide. Siha and HeLa cell apoptotic analysis was performed by flow cytometry. Real time-PCR and Western Blotting were used to analyze the expression of Bcl-2/Bax, Cyclin D1 and p16.

RESULTS

Viability in the combination group was significantly decreased as compared with either drug used alone. Expression change of Bcl-2/Bax, CyclinD1 and p16 appeared to play an important role in the synergistic killing effect on cervical cancer cell apoptosis.

CONCLUSION

Aspirin and triptolide combination treatment may have synergistic anti-tumor effects on cervical cancer cells.

Autophagy promotes paclitaxel resistance of cervical cancer cells: involvement of Warburg effect activated hypoxia-induced factor 1-α-mediated signaling

Paclitaxel is one of the most effective chemotherapy drugs for advanced cervical cancer. However, acquired resistance of paclitaxel represents a major barrier to successful anticancer treatment. In this study, paclitaxel-resistant HeLa sublines (HeLa-R cell lines) were established by continuous exposure and increased autophagy level was observed in HeLa-R cells. 3-Methyladenine or ATG7 siRNA, autophagy inhibitors, could restore sensitivity of HeLa-R cells to paclitaxel compared with parental HeLa cells. To determine the underlying molecular mechanism, differentially expressed proteins between HeLa and HeLa-R cells were identified by two-dimensional gel electrophoresis coupled with electrospray ionization quadrupole time-of-flight MS/MS. We found glycolysis-associated proteins were upregulated in HeLa-R cell lines. Inhibition of glycolysis by 2-deoxy-D-glucose or koningic acid could decrease autophagy and enhance sensitivity of HeLa-R cells to paclitaxel. Moreover, glycolysis could activate HIF1-α. Downregulation of HIF1-α by specific siRNA could decrease autophagy and resensitize HeLa-R cells to paclitaxel. Taken together, a possible Warburg effect activated HIF1-α-mediated signaling-induced autophagic pathway is proposed, which may provide new insight into paclitaxel chemoresistance.

[Stereotactic radiotherapy for pelvic tumors]

Extracranial stereotactic radiotherapy is booming. The development and spread of dedicated accelerators coupled with efficient methods of repositioning can now allow treatments of mobile lesions with moderate size, with high doses per fraction. Intuitively, except for the prostate, pelvic tumours, often requiring irradiation of regional lymph node drainage, lend little to this type of treatment. However, in some difficult circumstances, such as boost or re-radiation, stereotactic irradiation condition is promising and clinical experiences have already been reported.

Enrichment and characterization of cancer stem‑like cells from a cervical cancer cell line

Cancer stem cells (CSCs) are proposed to be responsible for tumor recurrence, metastasis and the high mortality rate of cancer patients. Isolation and identification of CSCs is crucial for basic and preclinical studies. However, as there are currently no universal markers for the isolation and identification of CSCs in any type of cancer, the method for isolating CSCs from primary cancer tissues or cell lines is costly and ineffective. In order to establish a reliable model of cervical cancer stem cells for basic and preclinical studies, the present study was designed to enrich cervical cancer CSCs using a nonadhesive culture system and to characterize their partial stemness phenotypes. Human cervical cancer cells (HeLa) were cultured using a nonadhesive culture system to generate tumor spheres. Their stemness characteristics were investigated through colony formation, tumor sphere formation, self-renewal, toluidine blue staining, chemoresistance, invasion assays, reverse transcription-polymerase chain reaction, immunofluorescence staining of putative stem cell markers, including octamer-binding transcription factor 4, SRY-box 2 and aldehyde dehydrogenase 1 family, member A1, and adipogenic differentiation induction. Typical tumor spheres were formed within 5–7 days under this nonadhesive culture system. Compared with the adherent parental HeLa cells, the colony formation capacity, self-renewal potential, light cell population, cell invasion, chemoresistance and expression of putative stem cell markers of the tumor sphere cells increased significantly, and a subpopulation of tumor sphere cells were induced into adipogenic differentiation. Using the nonadhesive culture system, a reliable model of cervical cancer stem cells was established, which is inexpensive, effective and simple compared with the ultra-low attachment serum free culture method. The stemness characteristics of the tumor sphere HeLa cells mirrored the CSC phenotypes. This CSC model may be useful for basic and preclinical studies of cervical cancer and other types of cancer.

Sustained complete response after maintenance therapy with topotecan and erlotinib for recurrent cervical cancer with distant metastases

Introduction

Recurrent cervical cancer is associated with a poor prognosis. Most treatment responses are partial and of short duration. The development of new therapies is vital to improve treatment for recurrent disease. Epidermal growth factor receptor (EGFR) inhibitors may have a role in this setting.

Case Description

A 53-year-old woman with stage IB2 squamous cell carcinoma of the cervix was initially treated with chemoradiation. Six months after completing treatment, she developed a recurrence in the common iliac and para-aortic lymph nodes above the previous radiation field and was treated with additional radiation therapy. Two years later, she developed recurrent disease in the left supraclavicular lymph nodes and was treated with chemoradiation followed by 3 cycles of adjuvant cisplatin and topotecan. She had a complete response and was placed on maintenance therapy with topotecan and erlotinib, which was well tolerated and produced minimal side effects. After 20 months of maintenance therapy, it was discontinued given the long interval without evidence of disease. The patient is currently without evidence of disease 5 years after completing the topotecan-erlotinib treatment.

Conclusion

We noted a sustained response in a patient with recurrent metastatic cervical cancer treated with radiotherapy, cisplatin, and topotecan followed by maintenance therapy with topotecan and erlotinib. Further evaluation of the role of EGFR inhibitors in this setting should be considered given their favorable toxicity profile and biological relevance.

Analysis of 30 patients with persistent or recurrent squamous cell carcinoma of the cervix within one year after concurrent chemoradiotherapy

OBJECTIVE

To investigate the recurrence sites, risk factors, and prognosis of patients with persistent or recurrent squamous cell carcinoma (SCC) of the cervix within one year after undergoing concurrent chemoradiotherapy (CCRT).

METHODS

Clinical data of 30 patients with persistent or recurrent SCC of the cervix within one year after CCRT between July 2006 and July 2011 were analyzed retrospectively. These data were compared with those of 35 SCC cases with no signs of recurrence after complete remission. These 35 patients were treated during the same period (between 2006 and 2011) and selected randomly.

RESULTS

Among these 30 patients, 25 exhibited distant metastases of which 14 were observed within 6 months after CCRT. Univariate analysis showed higher incidence of pelvic or para-aortic lymphadenectasis and SCC-ag >10 ng/mL in the group with persistent or recurrent disease before treatment (P<0.01). Multivariate analysis by logistic regression revealed that the pre-therapeutic pelvic or para-aortic lymph node enlargement and SCC-ag >10 ng/mL were the independent risk factors. Palliative chemotherapy was the main treatment option for patients with persistent or recurrent disease. The 2-year survival rate was 21.7%, and the median survival time was 17 months.

CONCLUSION

Patients with persistent or recurrent SCC of the cervix after CCRT exhibited a high rate of distant metastasis with poor prognosis. The pre-therapeutic pelvic or para-aortic lymph node enlargement and SCC-ag >10 ng/mL were identified as the independent risk factors for persistent or recurrent SCC within 1 year after CCRT.

ATL

Objective

The superiority of positron emission tomography (PET) with 2-deoxy-2-[18F]fluoro-D-glucose (FDG) over computed tomography and magnetic resonance imaging in detecting recurrent cervical cancer and determining the extent of the disease has been demonstrated in several clinical trials. However, there is a lack of data concerning the clinical impact of the extra findings. We report here a prospective clinical study aimed at investigating the clinical impact of FDG-PET findings on the treatment plans in recurrent cervical cancer.

Materials and Methods

Thirty-six patients with suspected recurrent cervical cancer underwent FDG-PET. Relapses were confirmed in 26 cases, and one case of primary lung cancer was found. The clinical impact of the FDG-PET results was assessed using a systematic scoring system with a 4-grade scale. Median follow-up time after FDG-PET was 33.1 months (range, 5–83 months) for all patients and 22.4 months (range, 5–83 months) for patients with positive PET results.

Results

More sites of metastases were detected with FDG-PET in 56% of the patients compared to the findings by conventional imaging. The results of FDG-PET led to a change in treatment modality for 33% of the patients; and for 22%, a change in dose or deliverance of treatment was recorded. Treatment intention was changed in 30%, in all but one patient, from curative to palliative. In 48% of the patients, the initially planned treatment was reduced regarding dose or extent, or was withheld.

Conclusion

In recurrent cervical cancer, FDG-PET provides clinically valuable information with a high impact on treatment decisions.

Impact of Chemoradiation on Prognosis in Stage IVB Cervical Cancer with Distant Lymphatic Metastasis

PURPOSE

The purpose of this study was to determine whether chemoradiation (CCR) is efficient for improving prognosis, compared with systemic chemotherapy (SC), in patients with stage IVB cervical cancer who have distant lymphatic metastasis.

MATERIALS AND METHODS

Among 2,322 patients with cervical cancer between January 2000 and March 2010, 43 patients (1.9%) had stage IVB disease. After exclusion of 19 patients due to insufficient data and hematogenous metastasis, 24 patients (1%) who received CCR (n=10) or SC (n=14) were enrolled. We compared tumor response, progression-free survival (PFS) and overall survival (OS), and disease recurrence between CCR and SC.

RESULTS

Complete response rates were 60% and 0% after CCR and SC (p<0.01). Grade 3 or 4 leukopenia was more common in patients treated with CCR (24.4% vs. 9.1%, p=0.03), whereas grade 3 or 4 neuropenia was more frequent in those treated with SC (28.4% vs. 11.1%, p=0.03). Development of grade 3 proctitis occurred as a late radiotherapy (RT)-related toxicity in only one patient (10%) treated with CCR. In addition, squamous cell carcinoma and CCR were favorable prognostic factors for improvement of PFS (adjusted hazard ratios [HRs], 0.17 and 0.12; 95% confidence intervals [CIs], 0.04 to 0.80 and 0.03 to 0.61), and only CCR was significant for improvement of OS (adjusted HR, 0.15; 95% CI, 0.02 to 0.90). However, no differences in the rate and pattern of disease recurrence were observed between CCR and SC.

CONCLUSION

CCR may be more effective than SC for improving survival, and can be regarded as a feasible method with some caution regarding late RT-related toxicity for treatment of stage IVB cervical cancer with distant lymphatic metastasis.

Glucose-regulated protein 94 modulates the therapeutic efficacy to taxane in cervical cancer cells

Cervical cancer is an important health issue for women worldwide, and the endoplasmic reticulum stress pathway is important for determining the chemotherapeutic response to cancer. However, the role of glucose-regulated protein 94 (GRP94) in taxane therapy for cervical cancer remains unclear. In this study, we generated GRP94 knockdown (GRP94-KD) Hela cells using short hairpin RNAs and found that GRP94-KD cells were resistant to taxane treatment in an MTT assay. Scrambled control cells demonstrated higher levels of apoptosis when treated with taxanes in comparison to GRP94-KD cells, as determined by cell cycle profiling, 4',6-diamidino-2-phenylindole staining, and terminal deoxynucleotidyl transferase-mediated nick end labeling staining. Caspase 3 and caspase 7 activity was also higher in scrambled control cells treated with taxane in comparison to GRP94-KD cells. Moreover, we found that depletion of GRP94 altered the levels of the apoptosis-related proteins Bcl2 and Bad, leading to sensitivity to taxane. Exposure to taxane also induced the expression of Bad in scrambled cells but not in GRP94-KD cells. In addition, the expression of Bcl2 was increased dramatically in GRP94-KD cells, whereas only a small increase was observed in scrambled cells. Therefore, we conclude that silencing GRP94 may increase resistance to taxane treatment in cervical cancer cells by altering the activation of the apoptosis pathway. In addition, GRP94 may represent a key biomarker for determining the therapeutic efficacy of taxane treatment in cervical cancer patients.

A tale of two approaches: complementary mechanisms of cytotoxic and targeted therapy resistance may inform next-generation cancer treatments

Chemotherapy and molecularly targeted approaches represent two very different modes of cancer treatment and each is associated with unique benefits and limitations. Both types of therapy share the overarching limitation of the emergence of drug resistance, which prevents these drugs from eliciting lasting clinical benefit. This review will provide an overview of the various mechanisms of resistance to each of these classes of drugs and examples of drug combinations that have been tested clinically. This analysis supports the contention that understanding modes of resistance to both chemotherapy and molecularly targeted therapies may be very useful in selecting those drugs of each class that will have complementing mechanisms of sensitivity and thereby represent reasonable combination therapies.

Morusin inhibits human cervical cancer stem cell growth and migration through attenuation of NF-κB activity and apoptosis induction

Cancer stem cells (CSCs) are believed to be responsible for tumor metastasis, recurrence, and high mortality of cancer patients due to their high tumorigenicity resistance to chemo-radiotherapy. Morusin possesses anti-cancer activity through attenuation of NF-κB activity, which is up-regulated in cancer stem cells. The purpose of this study is to confirm the growth and migration inhibition effect of morusin on human cervical CSCs, and to clarify its partial mechanism of activity. Human cervical CSCs were enriched using non-adhesive culture system. Their stemness characteristics were identified with tumor sphere formation, self-renewal, toluidine blue staining, migration assays, RT-PCR analysis, and immunofluorescence staining of putative stem cell markers, Oct4, SOX2, and ALDH1; the epithelial-to-mesenchymal (EMT) transition markers and relevant transcription factors were evaluated with Western blotting. The growth and migration inhibition effects of morusin on human cervical CSCs were tested by cell proliferation, tumor sphere formation, and transwell assay; apoptotic death of human cervical CSCs in response to morusin was measured with DAPI staining, apoptotic DNA fragmentation; NF-κBp65, Bcl-2, Bax, and caspase-3 protein expressions were detected through Western blotting. Under this non-adhesive culture system, typical tumor spheres appeared within 5-7 days, the tumor sphere formation, self-renewal, and cell migration, expressions of putative stem cell markers, EMT markers, and relevant transcription factors of the tumor sphere cells were increased significantly. After morusin treatment, the proliferation, tumor sphere formation, and migration of human cervical CSCs were decreased significantly, DAPI-stained apoptotic cells increased, apoptotic DNA fragmentations formed evidently; the expression levels of NF-κBp65 and Bcl-2 decreased significantly, Bax, and caspase-3 increased significantly in a dose-dependent manner. Using the non-adhesive culture system, human cervical CSCs were enriched and expanded. Morusin has the potential to target and kill CSCs, and can inhibit human cervical growth and migration through NF-κB attenuation mediated apoptosis induction.

Regulation of paclitaxel-induced programmed cell death by autophagic induction: A model for cervical cancer

Objective

Autophagy plays a vital role in homeostasis by combining organelles and cellular proteins with lysosome under starvation conditions. In addition, autophagy provides tumor cells with a source of energy. Continued autophagy will induce cells death. Here we aim to see if autophagic induction has an effect on conventional chemotherapeutic agents.

Methods

Rapamycin, or mammalian target of rapamycin and paclitaxel, apoptosis-inducing agents were used autophagy in HeLa cervical cancer cells.

Results

Growth inhibition of cells was not observed after the application of 0, 10, 20 nM of paclitaxel with or without rapamycin. Using a 5 nM concentration of paclitaxel, rapamycin administration inhibited cell growth significantly compared to no treatment. This implies the synergic antitumor effect of paclitaxel and rapamycin. Paclitaxel itself did not show any autophagic effect on cells but did show cell apoptosis by flow cytometry. Light chain 3, a microtubule-associated protein, which reflect autophagy, was increased with 5 nM of paclitaxel after pretreatment with 10 nM of rapamycin.

Conclusion

These findings suggest that the autophagic inducer, rapamycin, can potentiate autophagic cell death when added as an apoptosis-inducing chemotherapeutic agent. In conclusion, the control of autophagy may be a future target for chemotherapy.