Negative Cervical Cancer Research Articles

Surgical treatment of “intermediate risk” lymph node negative cervical cancer patients without adjuvant radiotherapy—A retrospective cohort study and review of the literature

ObjectivesThe role of adjuvant radiotherapy for lymph node-negative stage IB patients with tumor-related negative prognostic factors is not uniformly accepted. It is advocated based on the GOG 92 trial, which was initiated in 1989. The aim of the current study is to report the oncological outcome of “intermediate risk” patients treated by tailored surgery without adjuvant radiotherapy. Data from two institutions that refer these patients for adjuvant radiotherapy served as a control group. MethodsIncluded were patients with stage IB cervical cancer treated with radical hysterectomy and pelvic lymphadenectomy, who had negative pelvic lymph nodes but a combination of negative prognostic factors adopted from the GOG 92 trial. Data were obtained from prospectively collected databases of three institutions. Radical surgery was a single-treatment modality in one of them and in the remaining two institutes it was followed by adjuvant chemoradiation. ResultsIn 127 patients who received only radical surgery, with a median follow-up of 6.1 years, the local recurrence rate was 1.6% (2 cases), and total recurrence was 6.3% (8 cases). Disease-specific survival at 5 years was 95.7% (91.9%; 99.4%) and 91% (83.7%; 98.3%) at 10 years. The only significant factor for disease-specific survival was tumor size ≥4 cm (P = 0.032). The recurrence rate, local control or overall survival did not differ from the control group. Adjuvant radiotherapy was not a significant prognostic factor within the whole cohort. ConclusionsAn excellent oncological outcome, especially local control, can be achieved by both radical surgery or combined treatment in stage IB lymph node-negative cervical cancer patients with negative prognostic factors. The substantially better outcome than in the GOG 92 trial can be attributed to more accurate pre-operative and pathological staging and an improvement in surgical techniques.

Study on the methylation status of SPINT2 gene and its expression in cervical carcinoma.

Cervical cancer is one of the malignant tumors which seriously threaten the women health worldwide. SPINT2 is an endogenous inhibitor of hepatocyte growth factor activator and down regulated or even silenced in many human malignant tumors. This study was performed to explore the promoter methylation status of SPINT2 gene and the effect on its expression in cervical carcinoma. HPV-positive and -negative cervical cancer cell lines, 50 cases of cervical carcinoma tissues, and 20 cases of normal cervical tissues were used for this study. The methylation status of promoter and the first exon of SPINT2 gene were analyzed. The expression of SPINT2 was analyzed by qRT-PCR. HPV E6/E7 infection affects SPINT2 methylation rate in cell lines. SPINT2 methylation rate of HT-3E6/E7 was 8.8%, while the methylation rate of SPINT2 in HT-3 was 0%. In cervical tissues, the methylation rate of SPINT2 in cervical cancers was 54%, while the methylation rate of SPINT2 in normal cervical samples was 25%. As for cervical cancers, the methylation rate of SPINT2 gene was higher in grade 3 than those of grade 2. The expression of SPINT2 gene is regulated by its methylation status, and the methylation status of SPINT2 is altered by HPV infection. The aberrant methylation status of SPINT2 gene may play an important role in the development of cervical cancer.

Integrated analysis of HPV-mediated immune alterations in cervical cancer

ObjectiveHuman papillomavirus (HPV) infection is the primary cause of cervical cancer. HPV-mediated immune alterations are known to play crucial roles in determining viral persistence and host cell transformation. We sought to thoroughly understand HPV-directed immune alterations in cervical cancer by exploring publically available datasets. Methods130 HPV positive and 7 HPV negative cervical cancer cases from The Cancer Genome Atlas were compared for differences in gene expression levels and functional enrichment. Analyses for copy number variation (CNV) and genetic mutation were conducted for differentially expressed immune genes. Kaplan-Meier analysis was performed to assess survival and relapse differences across cases with or without alterations of the identified immune signature genes. ResultsGenes up-regulated in HPV positive cervical cancer were enriched for various gene ontology terms of immune processes (P=1.05E-14~1.00E-05). Integrated analysis of the differentially expressed immune genes identified 9 genes that displayed either CNV, genetic mutation and/or gene expression changes in at least 10% of the cases of HPV positive cervical cancer. Genomic amplification may cause elevated levels of these genes in some HPV positive cases. Finally, patients with alterations in at least one of the nine signature genes overall had earlier relapse compared to those without any alterations. The altered expression of either TFRC or MMP13 may indicate poor survival for a subset of cervical cancer patients (P=1.07E-07). ConclusionsWe identified a novel immune gene signature for HPV positive cervical cancer that is potentially associated with early relapse of cervical cancer.

The role of <em>calgranulin B</em> gene on the biological behavior of squamous cervical cancer in vitro and in vivo

ObjectiveThe objective of the study was to explore the role of calgranulin B gene on the biological behavior of squamous cervical cancer.MethodsDifferential transcription in calgranulin B gene between human papillomavirus (HPV)-positive and negative cervical cancer groups was identified, and the relationship between calgranulin B gene and matrix metalloproteinase (MMP) genes were explored using The Cancer Genome Atlas database. Subsequently, the role of calgranulin B on the cell proliferation, apoptosis, invasion and migration was investigated, through overexpression and/or underexpression of calgranulin B in cervical cancer cells. In addition, the effect of calgranulin B on the growth of the cervical cancer was studied via constructing xenograft model in BALB/c nude mice that either overexpressed or underexpressed calgranulin B.ResultsCalgranulin B gene transcription in cervical cancer was highly correlated with the high-risk HPV-16 and HPV-45. In addition, overexpression of calgranulin B increased cell proliferation, invasion and migration, whereas it did not significantly affect cell apoptosis. This effect was also confirmed by calgranulin B knockdown assay. Additionally, we found that the transcription of calgranulin B gene was negatively correlated with MMP15 and MMP24 genes, but positively associated with MMP25 genes in cervical cancer. Furthermore, calgranulin B significantly promoted the growth of cervical cancer in vivo.ConclusionCalgranulin B promotes cell proliferation, migration and invasion of squamous cervical cancer, possibly via regulation of MMPs. Whether there are synergistic actions between calgranulin B and HPV-16/HPV-45 infection on the squamous cervical carcinogenesis or progression need further study.

Surgical staging identified false HPV-negative cases in a large series of invasive cervical cancers

ObjectiveWe examined a large series of biopsy-proven invasive cervical cancers with surgical staging and HPV re-testing to estimate the relevance of HPV-negative cervical cancers in a Caucasian population. MethodsWe prospectively collected smears from 371 patients with a biopsy-proven diagnosis of cervical cancer for HC2 testing of high-risk HPV (HR-HPV). In HC2-negative cases, smears and paraffin embedded tissue blocks underwent additional HPV genotyping. ResultsHC2 tests showed 31/371 cases (8.8%) had negative findings. Surgical staging showed that 21/31 HC2-negative cases (68%) were not cervical cancer. Overall, 340/350 cases of primary cervical cancer confirmed by surgical staging tested HC2 positive (97.2%). Non-high-risk HPV subtypes were detected in five cases (one HPV-53, one HPV-70, and three HPV-73) and high-risk subtypes in four patients with HC2-negative cervical cancer (two HPV 16 and two HPV-18). The remaining case, a primary undifferentiated carcinoma of the uterine cervix, tested negative for HPV-DNA with all tests. ConclusionsThe main explanation for HPV-negative cervical cancer was a false diagnosis, followed by cancers associated with non-HR-HPV types, and false-negative HR-HPV results. Truly HPV negative seem to be very rare in Caucasian populations. Retrospective analyses without surgical staging may overestimate the proportion of HPV negative cervical cancers.

MiR-9, miR-21, and miR-155 as potential biomarkers for HPV positive and negative cervical cancer

BackgroundCervical cancer is the second leading cause of death among female patients with cancer in the world. High risk human papillomavirus has causal roles in cervical cancer initiation and progression by deregulating several cellular processes. However, HPV infection is not sufficient for cervical carcinoma development. Therefore, other genetic and epigenetic factors may be involved in this complex disease, and the identification of which may lead to better diagnosis and treatment. Our aim was to analyze the expression of microRNAs in cervical cancer cases positive or negative for HPV E6/E7 mRNA, and to assess their diagnostic usefulness and relevance.MethodsThe expression of three different microRNAs (miR-9, miR-21, and miR-155) in 52 formalin-fixed paraffin-embedded (FFPE) primary cervical cancer tissue samples and 50 FFPE normal cervical tissue samples were evaluated.ResultsMiR-9, miR-21, and miR-155 were significantly overexpressed in cervical cancer tissues compared to normal tissues (P < 0.001). MiR-21 and miR-155 expression combined with the HPV E6/E7 mRNA assay in HPV E6/E7 negative cervical cancer showed increased AUC of 0.7267 and 0.7000, respectively (P = 0.01, P = 0.04), demonstrating their potential as diagnostic tools. Moreover, miR-21 and miR-155 were predictors showing a 7 fold and 10.3 fold higher risk for HPV E6/E7 negative patients with cervical cancer (P = 0.024 and P = 0.017, respectively) while miR-155 was a predictor showing a 27.9 fold higher risk for HPV E6/E7 positive patients with cervical cancer (P < 0.0001).ConclusionsThere is a strong demand for additional, alternative molecular biomarkers for diagnosis and management of precancer patients. MiR-21 and miR-155 may be helpful in the prediction of both HPV positive and HPV negative cases of cervical cancer.

Proteomic Analysis of Normal and Cancer Cervical Cell Lines Reveals Deregulation of Cytoskeleton-associated Proteins.

Both HPV-positive and -negative cervical cancers are primarily associated with features of cell cycle and cytoskeletal disruption; however, the actual biological processes affected remain elusive. To this end, we systematically characterized the intracellular proteomic profiles of four distinct and informative cervical cell lines. Cell extracts from a normal cervical (HCK1T) and three cervical cancer cell lines, one HPV-negative (C33A), and two HPV-positive, SiHa (HPV16+) and HeLa (HPV18+), were analyzed by 2-dimensional electrophoresis and differentially expressed proteins were identified by MALDI-TOF mass spectrometry, while differential expression was confirmed by western blot analysis. In total, 113 proteins were found differentially expressed between the normal and the cervical cancer lines. Bioinformatics analysis revealed the actin cytoskeleton signaling pathway to be significantly affected, while up-regulation of cofilin-1, an actin depolymerizing factor, was documented and further validated by western blotting. Furthermore, two-way comparisons among the four cell lines, revealed a set of 18 informative differentially expressed proteins. These novel identified proteins provide the impetus for further functional studies to dissect the mechanisms operating in the two distinct pathways of cervical carcinogenesis.

TAK1 inhibitor 5Z-7-oxozeaenol sensitizes cervical cancer to doxorubicin-induced apoptosis.

Aberrant activation of nuclear factor-κB (NF-κB) allows cancer cells to escape chemotherapy-induced cell death and acts as one of the major mechanisms of acquired chemoresistance in cervical cancer. TAK1, a crucial mediator that upregulates NF-κB activation in response to cellular genotoxic stress, is required for tumor cell viability and survival. Herein, we examined whether TAK1 inhibition is a potential therapeutic strategy for treating cervical cancer. We found that TAK1 inhibitor 5Z-7-oxozeaenol significantly augmented the cytotoxic effects of Dox in a panel of cervical cancer cell lines. Treatment with 5Z-7-oxozeaenol hindered Dox-induced NF-κB activation and promoted Dox-induced apoptosis in cervical cancer cells. Moreover, 5Z-7-oxozeaenol showed similar effects in both positive and negative human papillomavirus-infected cervical cancer cells. Taken together, our results provide evidence that TAK1 inhibition significantly sensitizes cervical cancer cells to chemotherapy-induced cell death and supports the use of TAK1 inhibitor with current chemotherapies in the clinic for patients with refractory cervical cancer.

IκB kinase b Mediating the Downregulation of p53 and p21 by Lipopolysaccharide in Human Papillomavirus 16+ Cervical Cancer Cells.

Background:Cervical cancer is the second most common cancer of woman in the world, and human papillomavirus (HPV) infection plays an important role in the development of most of the cases. IκB kinase β (IKKβ) is a kinase-mediating nuclear factor kappa B (NF-κB) activation by phosphorylating the inhibitor of NF-κB (IκB) and is related by some diseases caused by virus infection. However, there is little known about the correlation between IKKβ and HPV infection in cervical cancer. This study aimed to investigate the expression of IKKβ protein in cervical cancer tissues and effects of inflammation on HPV positive or negative cervical cancer cells through detecting the expression of IKKβ, IκBα, p53, and p21 proteins after treated with lipopolysaccharide (LPS) to mimic bacterial infection. We also examined the effects of LPS on cervical cancer cells after blocking IKKβ with pharmacological inhibitor.Methods:Thirty-six matched specimens of cervical cancer and adjacent normal tissues were collected and analyzed in the study. The expression of IKKβ in the tissue specimens was determined by immunohistochemical staining. In addition, Western blot was used to detect the expression level changes of IKKβ, IκBα, p53, and p21 after LPS stimulated in the HPV16+ (SiHa) and HPV16− (C33A) cervical cancer cell lines. Furthermore, the effects of IKKβ inhibitor SC-514 on LPS-induced expression change of these proteins were investigated.Results:The expression of IKKβ was higher in cervical cancer than adjacent normal tissues, and there was no significant difference between tumor differentiation, size, and invasive depth with IKKβ expression. The LPS, which increased the expression level of IKKβ protein but decreased in the IκBα, p53 and p21 proteins, was illustrated in HPV16+ (SiHa) but not in HPV16− (C33A) cells. Moreover, IKKβ inhibitor SC-514 totally reversed the upregulation of IKKβ and downregulation of p53 and p21 by LPS in SiHa cells.Conclusions:IKKβ may mediate the downregulation of p53 and p21 by LPS in HPV16+ cervical cancer cells.

Doxycycline inhibits proliferation and induces apoptosis of both human papillomavirus positive and negative cervical cancer cell lines.

The clinical management of cervical cancer remains a challenge and the development of new treatment strategies merits attention. However, the discovery and development of novel compounds can be a long and labourious process. Drug repositioning may circumvent this process and facilitate the rapid translation of hypothesis-driven science into the clinics. In this work, we show that a FDA-approved antibiotic, doxycycline, effectively targets human papillomavirus (HPV) positive and negative cervical cancer cells in vitro and in vivo. Doxycycline significantly inhibits proliferation of a panel of cervical cancer cell lines. It also induces apoptosis of cervical cancer cells in a time- and dose-dependent manner. In addition, the apoptosis induced by doxycycline is through caspase-dependent pathway. Mechanism studies demonstrate that doxycycline affects oxygen consumption rate, glycolysis, and reduces ATP levels in cervical cancer cells. In HeLa xenograft mouse model, doxycycline significantly inhibits growth of tumour. Our in vitro and in vivo data clearly demonstrate the inhibitory effects of doxycycline on the growth and survival of cervical cancer cells. Our work provides the evidence that doxycycline can be repurposed for the treatment of cervical cancer and targeting energy metabolism may represent a potential therapeutic strategy for cervical cancer.

Identification of HPV Integration and Genomic Patterns Delineating the Clinical Landscape of Cervical Cancer

Cervical cancer is one of the most common cancers in women worldwide. During their life time the vast majority of women become infected with human papillomavirus (HPV), but interestingly only a small portion develop cervical cancer and in the remainder infection regresses to a normal healthy state. Beyond HPV status, associated molecular characterization of disease has to be established. However, initial work suggests the existence of several different molecular classes, based on the biological features of differentially expressed genes in each subtype. This suggests that additional risk factors play an important role in the outcome of infection. Host genomic factors play an important role in the outcome of such complex or multifactor diseases such as cervical cancer and are also known to regulate the rate of disease progression. The aim of this review was to compile advances in the field of host genomics of HPV positive and negative cervical cancer and their association with clinical response.

The impact of HIV infection on women receiving radiation for cervical cancer

AbstractBackground: The objective of the study was to compare patient characteristics, treatment toxicity and interruptions, and survival in human immunodeficiency virus (HIV)-positive and HIV-negative cervical cancer patients receiving radiation as primary or adjuvant treatment.Method: Demographics, clinical and tumour characteristics, and the outcomes of 51 HIV-positive and 47-HIV negative consecutive cervical cancer patients were assessed and compared, including co-morbidities, performance status, treatment type and toxicities, and survival.Results: HIV-positive women were 13 years younger (p < 0.001), more often had anaemia (p 0.021) and needed pretreatment blood transfusion (p 0.037) more often than HIV-negative women. Performance status, kidney function, International Federation of Gynecology and Obstetrics stage, histology types and treatment intent and planning did not differ between the two groups. Treatment interruptions (p 0.004), transfusion during treatment (p 0.012), treatment toxicities (p ...

Prospective Study of Sentinel Lymph Node Biopsy Without Further Pelvic Lymphadenectomy in Patients With Sentinel Lymph Node–Negative Cervical Cancer

The aim of the present study was to evaluate the incidence of lymphedema and cancer recurrence rate in patients with cervical cancer who undergo sentinel lymph node (SLN) biopsy alone in the absence of SLN metastases. The study included 35 consecutive patients with cervical cancer scheduled for radical hysterectomy at Tohoku University Hospital between May 2006 and July 2009. All patients had International Federation of Gynecology and Obstetrics stages IA1 to IIA1 disease. Patients in whom SLNs were detected unilaterally or not detected and/or whose lymph nodes were diagnosed intraoperatively as positive metastasis underwent systemic pelvic lymphadenectomy. Patients who were found negative for SLN metastasis did not undergo further pelvic lymphadenectomy. The mean number of detected SLNs was 4.1 (range, 1-11). True lymph node metastasis could be detected in 11 (31%) of the 35 cases. Intraoperative frozen section identified correctly in 8 of 11 metastatic patients. Twenty-three patients underwent SLN biopsy alone without systematic pelvic lymphadenectomy. None of the 23 patients diagnosed with negative SLNs have experienced a lymph node recurrence in the pelvic cavity. New symptomatic lower extremity lymphedema was identified in 2 (8.7%) of the 23 patients who underwent SLN biopsy alone and in 5 (42%) of 12 patients who underwent systematic lymphadenectomy. Radical hysterectomy with SLN biopsy alone seems to be a safe and effective strategy for detection of lymph node metastasis and for reducing the number of patients with lower extremity lymphedema, but a more convenient and sensitive procedure for intraoperative diagnosis needs to be established.

The mitochondrial transporter SLC25A43 is frequently deleted and may influence cell proliferation in HER2-positive breast tumors

BackgroundOverexpression of the human epidermal growth factor receptor (HER) 2 is associated with poor prognosis and shortened survival in breast cancer patients. HER2 is a potent activator of several signaling pathways that support cell survival, proliferation and metabolism. In HER2-positive breast cancer there are most likely unexplored proteins that act directly or indirectly downstream of well established pathways and take part in tumor development and treatment response.MethodsIn order to identify novel copy number variations (CNVs) in HER2-positive breast cancer whole-genome single nucleotide polymorphism (SNP) arrays were used. A PCR-based loss of heterozygosis (LOH) assay was conducted to verify presence of deletion in HER2-positive breast cancer cases but also in HER2 negative breast cancers, cervical cancers and lung cancers. Screening for mutations was performed using single-strand conformation polymorphism (SSCP) followed by PCR sequencing. Protein expression was evaluated with immunohistochemistry (IHC).ResultsA common deletion at chromosome Xq24 was found in 80% of the cases. This locus harbors the gene solute carrier (SLC) family 25A member 43 (SLC25A43) encoding for a mitochondrial transport protein. The LOH assay revealed presence of SLC25A43 deletion in HER2-positive (48%), HER2-negative (9%), cervical (42%) and lung (67%) cancers. HER2-positive tumors with negative or low SLC25A43 protein expression had significantly lower S-phase fraction compared to tumors with medium or high expression (P = 0.024).ConclusionsWe have found deletion in the SLC25A43 gene to be a common event in HER2-positive breast cancer as well as in other cancers. In addition, the SLC25A43 protein expression was shown to be related to S-phase fraction in HER2-positive breast cancer. Our results indicate a possible role of SLC25A43 in HER2-positive breast cancer and support the hypothesis of altered mitochondrial function in cancer.

Abstract B78: Evaluation of letrozole for the prevention and inhibition of tumor growth in human cervical cancer xenograft mouse models

Abstract Purpose: To evaluate the efficacy of letrozole, a third generation aromatase inhibitor, for the prevention or delay of cervical cancer recurrence in either human papillomavirus (HPV) positive (HeLa) or HPV negative (C-33a) cervical cancer xenograft mouse models. Method: In this three arm study with two xenograft cervical cancer mouse models, HeLa (HPV 16 positive), and C-33a (HPV negative), the efficacy of letrozole was evaluated in prevention and tumor growth inhibition. Sixty mice were divided into six groups of ten mice each of treatment arm, vehicle control arm and no treatment arm for two cell lines. Mice in the treatment arm received letrozole 10 μg orally once daily every day beginning seven days before the inoculation with respective cancer cells and continued until day 90 of the study. Mice were injected subcutaneously on eighth day of the study with 0.5 million cells of respective cell line. Tumor growth was assessed three times a week. After 90 days of letrozole treatment, a 30 day period without drug was observed to evaluate tumor growth. At the end of the study, tumors were extracted and the expression of estrogen receptor alpha (ERα and estrogen receptor beta (ERβ was evaluated from the extracted protein by immunoblotting and RT-PCR was completed on DNA samples from extracted tumors to evaluate the HPV expression. Results: After 90 days of continuous treatment, letrozole inhibited microscopic cervical tumor growth in the HeLa mouse models demonstrated by 45% reduction in tumor volume in the HeLa letrozole treated mice compared to the no treatment control (p &amp;lt; 0.05). Off treatment, the HeLa letrozole treated mice also had slower rate of tumor progression by 38% compared to untreated group (p&amp;lt; 0.05). In addition, overall survival (OS) was improved by 75% in HeLa letrozole arm with (OS of 40% in the letrozole arm compared to 10% in the no treatment arm). While there was only an 18% reduction (p= 0.63) in tumor volume in the C-33a letrozole treated mice compared to the no treatment control, once treatment was stopped, the mice that had been receiveing letrozole had a slower rate of tumor progression by 37% (p &amp;lt; 0.07). There was no survival benefit observed in the C-33a tumor model. In both studies, no change in ERa, ERb, or HPV expression was observed in the letrozole treatment group compared to no treatment group. Conclusion: Although there was no change in ERα, ERβ, or HPV expression observed in this study, the response data in the HPV 16 positive HeLa tumor model compared to the HPV negative C-33a tumor model suggests HPV expression is associated with the potential activity of letrozole for the prevention of cervical cancer recurrence/progression. Additional studies are needed to elucidate the differences of letrozole activity in presence and absence of HPV expression. Overall, this preliminary data indicates a potential agent for the prevention and treatment of cervical cancer recurrence. Citation Information: Cancer Prev Res 2011;4(10 Suppl):B78.

Membranous Expression of Ectodomain Isoforms of the Epidermal Growth Factor Receptor Predicts Outcome after Chemoradiotherapy of Lymph Node–Negative Cervical Cancer

We compared the prognostic significance of ectodomain isoforms of the epidermal growth factor receptor (EGFR), which lack the tyrosine kinase (TK) domain, with that of the full-length receptor and its autophosphorylation status in cervical cancers treated with conventional chemoradiotherapy. Expression of EGFR isoforms was assessed by immunohistochemistry in a prospectively collected cohort of 178 patients with squamous cell cervical carcinoma, and their detection was confirmed with Western blotting and reverse transcriptase PCR. A proximity ligation immunohistochemistry assay was used to assess EGFR-specific autophosphorylation. Pathways associated with the expression of ectodomain isoforms were studied by gene expression analysis with Illumina beadarrays in 110 patients and validated in an independent cohort of 41 patients. Membranous expression of ectodomain isoforms alone, without the coexpression of the full-length receptor, showed correlations to poor clinical outcome that were highly significant for lymph node-negative patients (locoregional control, P = 0.0002; progression-free survival, P < 0.0001; disease-specific survival, P = 0.005 in the log-rank test) and independent of clinical variables. The ectodomain isoforms were primarily 60-kD products of alternative EGFR transcripts. Their membranous expression correlated with transcriptional regulation of oncogenic pathways including activation of MYC and MAX, which was significantly associated with poor outcome. This aggressive phenotype of ectodomain EGFR expressing tumors was confirmed in the independent cohort. Neither total nor full-length EGFR protein level, or autophosphorylation status, showed prognostic significance. Membranous expression of ectodomain EGFR isoforms, and not TK activation, predicts poor outcome after chemoradiotherapy for patients with lymph node-negative cervical cancer.

TLR9 expression and its role in chemosensitivity to DDP in human cervical cancer cells in vitro

Inflammation and infection play an important role in the pathogenesis of many cancers. Toll-like receptors (TLRs) are a class of pattern recognition receptors that recognize conserved components of microbes and trigger the immune response against invading microorganisms. Toll-like receptor 9 (TLR9) recognizes non-methylated cytosine-phosphateguanosine (CpG) DNA sequences which are the surrogate for viral DNA. TLR9 may react to tumor development and progression during chronic inflammation that involves the tumor microenvironment. In order to study the role of TLR9 in cervical cancer, we analyzed the TLR9 expression in different types of HPV infection cervical cancer cells. Then we detected if CpG sequences influenced the TLR9 expression and the sensitivity to cisplatin (DDP) of these cervical cancer cells in vitro. The expression of TLR9 mRNA and protein in SiHa, Hela and C33A cells was detected by RT-PCR and Western blotting. Real-time PCR was used to examine the TLR9 expression changes induced by CpG. Chemosensitivity of the cervical cancer cells to cisplatin (DDP) was measured by MTT. It was observed that the expression of TLR9 mRNA and protein was increased gradually in SiHa (HPV16+), Hela (HPV18+) and C33A (HPV-) cells. Low doses of CpG increased the TLR9 expression only in C33A (HPV-) cells, but not in SiHa (HPV16+) and Hela (HPV18+) cells. Furthermore, low dose of CpG significantly increased the sensitivity of C33A (HPV-) cells, but not that of SiHa (HPV16+) and Hela (HPV18+) cells. These results indicated that TLR9 may serve as a protective agent in HPV negative cervical cancer cells. It was concluded that TLR9 could improve the sensitivity to DDP in HPV negative cervical cancer cells and might represent a potential therapeutic option in clinical practice.

Twelve-year experience with laparoscopic radical hysterectomy and pelvic lymphadenectomy in cervical cancer

Objectives This study aims to evaluate the morbidity, oncological outcome, and prognostic factors of cervical cancer patients treated with laparoscopic radical hysterectomy and pelvic lymphadenectomy (LRH). Methods Patients with cervical cancer undergoing LRH at the First People's Hospital of Foshan between August 1998 and March 2010 were enrolled in this study. The medical records were reviewed. Results A total of 240 patients were identified. According to FIGO stage, the number of patients with stage Ia2, Ib1, Ib2, IIa, and IIb was 2, 163, 34, 35, and 6, respectively. The conversion rate was 1.25%. Intraoperative and postoperative complications occurred in 7.08% and 9.16% patients, respectively. Other medical problems included 74 cases (30%) of bladder dysfunction. Excluding the lost cases, the median follow-up of 221 cases was 35 months, and 5-year survival rate for Ia2, Ib1, Ib2, IIa was 100%, 82%, 66%, 60%, respectively. Univariate analysis showed factors impacting the survival rate were FIGO stage > Ib1, non-squamous histologic type, deep cervical stromal invasion, and lymph node metastasis ( P = 0.027, 0.023, 0.007, 0.000). The Cox-proportional hazards regression analysis indicated that only lymph node metastasis (OR = 3.827, P = 0.000) was independent of poor prognostic factor. The 5-year survival rates in Ib1 were 88% with negative lymph nodes and 59% with positive lymph nodes ( P = 0.000). Conclusions Our data demonstrate that LRH can be performed in stage Ia2–Ib1 or less advanced node negative cervical cancer patients without compromising survival. The feasibility of LRH for more advanced patients needs further investigations.

Curcumin counteracts the proliferative effect of estradiol and induces apoptosis in cervical cancer cells

Cervical cancer is the most common cancer in Indian females and is associated with infection with high-risk Human papilloma viruses (HPVs) which encode viral oncoprotein E6 and E7. Estradiol has been established as a risk factor for cervical cancer and has been shown to play a synergistic role with viral oncoproteins. Curcumin (Diferuloyl methane), a chemopreventive agent, is a natural compound extracted from Curcuma longa that allows suppression and retardation of carcinogenesis in many types of cancer and is currently being tested in various human clinical trials as it has been found to be well tolerated at higher doses with a relatively well established safety profile. The objective of this study was to test the effect of curcumin on HPV-positive and negative cervical cancer cell lines HeLa, SiHa, CaSki, and C33A pretreated with estradiol. It was found that HPV-positive cells pretreated with estradiol show reduced apoptosis as compared to curcumin by itself. However, curcumin was able to counteract the proliferative response of estradiol, and induce apoptosis. There was no difference in percentage apoptosis as compared to estradiol pretreatment in HPV-negative cell line C33A. Molecular studies showed elevation of Telomerase, viral oncoproteins E6 and E7, PCNA, p16, Cyclin D1 in HPV-positive cell lines on treatment with estradiol but after treatment with curcumin the level of E7, PCNA, and Cyclin D1 was reduced but the level of E6, Telomerase, and p16 was unaltered. Furthermore, estradiol-pretreated HPV-negative cell line C33A showed reduction in level of Telomerase, PCNA, p16, and activation of both p53 and p73 tumor suppressor proteins, thus, demonstrating the importance of E6 in estradiol-mediated protective effect.

Triggering of death receptor apoptotic signaling by human papillomavirus 16 E2 protein in cervical cancer cell lines is mediated by interaction with c-FLIP

Human papillomavirus (HPV) E2 gene disruption is one of the key features of HPV-induced cervical malignant transformation. Though it is thought to prevent progression of carcinogenesis, the pro-apoptotic function of E2 protein remains poorly understood. This study shows that expression of HPV16 E2 induces apoptosis both in HPV-positive and -negative cervical cancer cell lines and leads to hyperactivation of caspase-8 and caspase-3. Activation of these signaling factors is responsible for the observed sensitivity to apoptosis upon treatment with anti-Fas antibody or TNF-α. In addition, immunoprecipitation experiments clearly show an interaction between HPV16 E2 and c-FLIP, a key regulator of apoptotic cell death mediated by death receptor signaling. Moreover, c-FLIP and a caspase-8 inhibitor protect cells from HPV16 E2-mediated apoptosis. Overexpression of c-FLIP rescues cervical cancer cells from apoptosis induced by HPV16 E2 protein expression. The data suggest that HPV16 E2 abrogates the apoptosis-inhibitory function of c-FLIP and renders the cell hypersensitive to the Fas/FasL apoptotic signal even below threshold concentration. This suggests a novel mechanism for deregulation of cervical epithelial cell growth upon HPV-induced transformation, which is of great significance in developing therapeutic strategies for intervention of cervical carcinogenesis.