The glycosyltransferase ST6Gal-I is enriched in cancer stem-like cells in colorectal carcinoma and contributes to their chemo-resistance

Purpose

Presence of cancer stem cells (CSCs) contributes to tumor outgrowth, chemo-resistance and relapse in some cancers including colorectal carcinoma (CRC). The current characterization methods of CSCs in CRC only allows enrichment of CSCs but not their purification. Recent reports showed that ST6 beta-galactoside alpha-2,6-sialyltransferase 1 (ST6Gal-I) plays an essential role in protecting tumor cells against harsh environment like oxidative stress and nutrient deprivation. Therefore, whether ST6Gal-I may be highly expressed in CSCs or whether it may enhance resistance of tumor cells to chemotherapy deserves exploration.

Method

ST6Gal-I levels were determined in CRC specimens, compared to paired normal colorectal tissue, and examined in CD133+ vs CD133? CRC cells, and CD44+ vs CD44? CRC cells. ST6Gal-I levels and their association with patient survival were examined. In vivo, 2 CRC cell lines Caco-2 and SW48 were transduced with two lentiviruses, one lentivirus carrying a green fluorescent protein reporter and a luciferase reporter under a cytomegalovirus promoter to allow tracing tumor cells by both fluorescence and luciferase activity, and one lentivirus carrying a nuclear red fluorescent protein under the control of ST6Gal-I promoter to allow separation of ST6Gal-I+ vs ST6Gal-I? CRC cells. Tumor sphere formation, resistance to fluorouracil-induced apoptosis, and frequency of tumor formation after serial adoptive transplantation were done on ST6Gal-I+ vs ST6Gal-I? CRC cells.

Result

ST6Gal-I levels were significantly upregulated in clinically obtained CRC specimens, compared to paired normal colorectal tissue. Poorer patient survival was detected in ST6Gal-I-high CRC, compared to ST6Gal-I-low subjects. Higher levels of ST6Gal-I were detected in CD133+ CRC cells than CD133? CRC cells, and in CD44+ CRC cells than in CD44? CRC cells. Compared to ST6Gal-I? CRC cells, ST6Gal-I+ CRC cells generated significantly more tumor spheres in culture, were more resistant to fluorouracil-induced apoptosis likely through upregulating cell autophagy, and generated tumor more frequently after serial adoptive transplantation.

Conclusion

ST6Gal-I may be highly expressed in the cancer stem-like cells in CRC and enhances cancer cell resistance to chemotherapy.

     

Knockdown of OCT4 may sensitize NSCLC cells to cisplatin

Purpose

Cisplatin is commonly used in non-small-cell lung cancer (NSCLC) chemotherapy; however, chemoresistance to cisplatin remains a great clinical challenge. Octamer-binding protein 4 (OCT4) has been reported to be overexpressed in NSCLC. In this study, we aimed to investigate the potential role of OCT4 in NSCLC with chemoresistance to cisplatin.

Methods

Expressions of OCT4 was detected in NSCLC tissues and cell lines. We utilized siRNA to knock down OCT4 expression in human NSCLC cells and analyzed their phenotypic changes.

Results

We found that the difference of OCT4 expression between NSCLC and the adjacent non-tumourous tissues was statistically significant. Knockdown of OCT4 in NSCLC cells could decrease cell proliferation, and potentiate apoptosis induced by cisplatin, suggesting OCT4 may contribute to cisplatin resistance in NSCLC.

Conclusion

Our findings indicate that targeting OCT4 could improve cisplatin effect in NSCLC, confirming their role in modulating cisplatin sensitivity.

     

Glycogene expression profiles based on microarray data from cervical carcinoma HeLa cells with partially silenced E6 and E7 HPV oncogenes

Background

Aberrant glycosylation is a characteristic of tumour cells. The expression of certain glycan structures has been associated with poor prognosis. In cervical carcinoma, changes in the expression levels of some glycogenes have been associated with lymph invasion. Human papillomavirus (HPV) infection is one of the most important factors underlying the development of cervical cancer. The HPV oncoproteins E6 and E7 have been implicated in cervical carcinogenesis and can modify the host gene expression profile. The roles of these oncoproteins in glycosylation changes have not been previously reported.

Methods

To determine the effect of the E6 and E7 oncoproteins on glycogene expression we partially silenced the E6 and E7 oncogenes in HeLa cells, we performed a microarray expression assay to identify altered glycogenes and quantified the mRNA levels of glycogenes by RT-qPCR. A protein-protein interaction network was constructed to identify potentially altered glycosylation pathways.

Results

The microarray analysis showed 9 glycogenes that were upregulated and 7 glycogenes that were downregulated in HeLa shE6/E7 cells. Some of these genes participate in glycosylation related to Notch proteins and O-glycans antigens.

Conclusions

Our results support that E6 and E7 oncoproteins could modify glycogene expression the products of which participate in the synthesis of structures implicated in proliferation, adhesion and apoptosis.

     

Synergistic anticancer effect of panobinostat and topoisomerase inhibitors through ROS generation and intrinsic apoptotic pathway induction in cervical cancer cells

Purpose

Various combinations of drugs may be effective in the treatment of different types of cancer. Previously, we have shown that combinations of the histone deacetylase inhibitor panobinostat and the topoisomerase inhibitors topotecan or etoposide act synergistically, but the underlying mode of action has remained unknown. Here, we aimed at uncovering the mechanisms underlying this synergism.

Methods

The effects of (combinations of) panobinostat and topotecan or etoposide on cervical cancer-derived HeLa and SiHa cells were assessed using morphological evaluations, scratch wound healing assays, cell cycle analyses, AO/EB staining assays, Annexin V/PI staining assays, reactive oxygen species (ROS) and mitochondrial membrane potential measurements and Western blotting.

Results

We found that combinations of panobinostat and the topoisomerase inhibitors topotecan or etoposide synergistically enhanced the induction of apoptosis in both HeLa and SiHa cells. This enhanced apoptosis induction was found to be mediated through increased ROS production and induction of the mitochondrial apoptotic pathway. We also found that the combination treatment resulted in inhibition of the PI3K/AKT and NF-κB pro-survival pathways and in activation of the ERK pathway, which is associated with intrinsic apoptosis.

Conclusions

From our data we conclude that combinations of panobinostat and the topoisomerase inhibitors topotecan or etoposide provoke strong cell death responses in cervical cancer-derived cells via induction of the intrinsic apoptotic pathway. Since this drug combination may potentially be effective in the treatment of cervical cancer, further preclinical investigations are warranted.

     

Fluidic shear stress increases the anti-cancer effects of ROS-generating drugs in circulating tumor cells

Purpose

Many anti-cancer drugs are used in chemotherapy; however, little is known about their efficacy against circulating tumor cells (CTCs). In this study, we investigated whether the pulsatile fluidic shear stress (SS) in human arteries can affect the efficacy of anti-cancer drugs.

Methods

Cancer cells were circulated in our microfluidic circulatory system, and their responses to drug and SS treatments were determined using various assays. Breast and cervical cancer cells that stably expressed apoptotic sensor proteins were used to determine apoptosis in real-time by fluorescence resonance energy transfer (FRET)-based imaging microscopy. The occurrence of cell death in non-sensor cells were revealed by annexin V and propidium iodide staining. Cell viability was determined by MTT assay. Intracellular reactive oxygen species (ROS) levels were determined by staining cells with two ROS-detecting dyes: 2′,7′-dichlorofluorescin diacetate and dihydroethidium.

Results

Fluidic SS significantly increased the potency of the ROS-generating drugs doxorubicin (DOX) and cisplatin but had little effect on the non-ROS-generating drugs Taxol and etoposide. Co-treatment with SS and ROS-generating drugs dramatically elevated ROS levels in CTCs, while the addition of antioxidants abolished the pro-apoptotic effects of DOX and cisplatin. More importantly, the synergistic killing effects of SS and DOX or cisplatin were confirmed in circulated lung, breast, and cervical cancer cells, some of which have a strong metastatic ability.

Conclusions

These findings suggest that ROS-generating drugs are more potent than non-ROS-generating drugs for destroying CTCs under pulsatile fluidic conditions present in the bloodstream. This new information is highly valuable for developing novel therapies to eradicate CTCs in the circulation and prevent metastasis.

     

A risk prediction model to allow personalized screening for cervical cancer

Importance

Cervical cancer screening guidelines are in evolution. Current guidelines do not differentiate recommendations based on individual patient risk.

Objective

To derive and validate a tool for predicting individualized probability of cervical intraepithelial neoplasia grade 2 or higher (CIN2+) at a single time point, based on demographic factors and medical history.

Design

The study design consisted of an observational cohort with hierarchical generalized linear regression modeling.

Setting

The study was conducted in a setting of 33 primary care practices from 2004 to 2010.

Participants

The participants of the study were women aged ≥?30 years.

Main outcome and measures

CIN2+ was the main outcome on biopsy, and the following predictors were included: age, race, marital status, insurance type, smoking history, median income based on zip code, prior human papilloma virus (HPV) results.

Results

The final dataset included 99,319 women. Of these, 745 (0.75%) had CIN2+. The multivariable model had a C-statistic of 0.81. All factors but race were independently associated with CIN2+. The model categorized women as having below-average CIN2+ risk (0.15% predicted vs. 0.12% observed risk), average CIN2+ risk (0.42% predicted vs. 0.36% observed), and above-average CIN2+ risk (1.76% predicted vs. 1.85% observed). Before screening, women at below-average risk had a risk of CIN2+ well below that of women with ASCUS and HPV negative (0.12 vs. 0.20%).

Conclusions and relevance

A multivariable model using data from the electronic health record was able to stratify women across a 50-fold gradient of risk for CIN2+. After further validation, use of a similar model could enable more targeted cervical cancer screening.

     

Cancers et environnement : explorer les comportements de recherche et les sources d’information des personnes atteintes et non atteintes d’un cancer

Aim

To explore information-seeking behaviors on links between cancers and environment.

Method

Focus groups and individual semi-structured interviews realized, respectively, with individuals without and with personal cancer experience.

Results

The majority of respondents reported informationscanning behaviors. Only half cancer patients searched for information regarding the links between cancers and environment.

Conclusion

Little information is sought on links between cancers and environment.

     

SIRT6 drives epithelial-to-mesenchymal transition and metastasis in non-small cell lung cancer via snail-dependent transrepression of KLF4

Background

Epithelial-to-mesenchymal transition (EMT) contributes to the invasion and metastasis of epithelial tumors. Sirtuin 6 (SIRT6), an NAD-dependent deacetylase, is known to promote metastasis of non-small cell lung cancer (NSCLC).

Methods

In this work, we determined the role of SIRT6 in the EMT of NSCLC cells and identified the key EMT-related genes involved in the oncogenic activity of SIRT6.

Results

We report that depletion of SIRT6 inhibits transforming growth factor-β1 (TGF-β1)-induced EMT in A549 and H1299 NSCLC cells, which is rescued by ectopic expression of SIRT6. Knockdown of SIRT6 leads to a reduction in Snail protein without affecting the mRNA level. Immunoprecipitation experiments demonstrate a physical association between SIRT6 and Snail. SIRT6 deacetylates Snail and prevents its proteasomal degradation. Silencing of Snail blunts SIRT6-induced NSCLC cell migration and invasion, while overexpression of Snail restores the invasion and EMT in SIRT6-depleted NSCLC cells. SIRT6 depletion leads to an upregulation of kruppel-like factor 4 (KLF4) and reduced Snail binding to the promoter of Klf4 in NSCLC cells. Knockdown of KLF4 rescues the invasive capacity in SIRT6-depleted NSCLC cells. Conversely, co-expression of KLF4 impairs SIRT6-induced aggressive behavior. In vivo data further demonstrate that SIRT6-induced NSCLC metastasis is antagonized by overexpression of KLF4.

Conclusions

These findings provide mechanistic insights into the pro-metastatic activity of SIRT6 and highlight the role of the SIRT6/Snail/KLF4 axis in regulating EMT and invasion of NSCLC cells.

     

Operative Therapie des Zervixkarzinoms

Background

The surgical treatment of cervical cancer is dependent on the stage and should follow complex but accurately defined algorithms and also consider the general condition of the patient, tumor type, tumor biology (and additional risk factors) as well as personal and family planning of patients.

Material and methods

Selective literature and guideline search in PubMed.

Results

At present only surgical staging can provide exact information regarding potential tumor spread throughout the abdominal cavity, detection or exclusion of lymph node involvement and involvement of neighboring organs. Patients with early cervical cancer should if possible always undergo minimally invasive surgical procedures because in experienced hands the surgical and oncological outcomes of minimally invasive surgery are at least equal to those of laparotomy and with a clearly lower perioperative and postoperative morbidity. The sentinel lymphadenectomy concept provides the possibility of an adequate staging by omission of radical lymphadenectomy and leads to a significant reduction of associated complications.

Conclusion

The complex surgical interventions for cervical cancer should not be carried out sporadically but only in specialized centers, which are equipped with a complete, interdisciplinary infrastructure.

     

Decline in Cancer Screening in Vulnerable Populations? Results of the EDIFICE Surveys

Background

We studied cancer screening over time and social vulnerability via surveys of representative populations.

Methods

Individuals aged 50–75 years with no personal history of cancer were questioned about lifetime participation in screening tests, compliance (adherence to recommended intervals [colorectal, breast and cervical cancer]) and opportunistic screening (prostate and lung cancer).

Results

The proportion of vulnerable/non-vulnerable individuals remained stable between 2011 and 2016. In 2011, social vulnerability had no impact on screening participation, nor on compliance. In 2014, however, vulnerability was correlated with less frequent uptake of colorectal screening (despite an organised programme) and prostate cancer screening (opportunistic), and also with reduced compliance with recommended intervals (breast and cervical cancer screening). In 2016, the trends observed in 2014 were substantiated and even extended to breast, colorectal and cervical cancer screening uptakes. Social vulnerability has an increasingly negative impact on cancer screening attendance. The phenomenon was identified in 2014 and had expanded by 2016.

Conclusion

Although organised programmes have been shown to ensure equitable access to cancer screening, this remains a precarious achievement requiring regular monitoring. Further studies should focus on attitudes of vulnerable populations and on ways to improve cancer awareness campaigns.

     

Körperliche Beschwerden und psychosoziale Folgen nach einer Zervixkarzinomerkrankung

Background

In Germany cervical cancer is the third most frequent female genital tumour. Due to early diagnosis and the improved medical treatment more than two thirds of patients survive. Thus, quality of life of cervical cancer survivors is important. The aim of this article is to describe the physical and psychosocial sequelaes of cervical cancer as well as supportive care needs.

Methods

A narrative overview is given based on current research.

Results

Physical long-term effects are vaginal dryness/shortening, bladder and bowel dysfunction and heat flashes. In some studies anxiety, depression and fatigue were reported to be higher in cervical cancer patients compared with controls. An essential problem was found in or is located in the area of femininity, sexuality and intimacy. Women with cervical cancer report a decreased sexual desire and painful sexual intercourse. The type of treatment has an influence on quality of life. Nerve-sparing operation techniques are associated with fewer symptoms. Furthermore, women with radiotherapy had a poorer quality of life than women without radiotherapy. Notably supportive care needs were documented for sexuality and the need of information about cervical cancer.

Conclusion

Adequately information in pre-, postoperative and in aftercare substantially facilitate or enable women with cervical cancer to deal with the physical and psychosocial consequences of the cancer itself and cancer treatment. Thus a good continued physician–patient communication, including taboo topics like sexuality, can even contribute to the wellbeing of the women.

     

Humane Papillomaviren und Zervixkarzinom

Background

Cervical cancer is the fourth most commonly occurring malignancy in women worldwide. Extrapolations by the Robert Koch Institute on the basis of cancer registry data in Germany showed that approximately 4600 women were diagnosed with cervical cancer in 2012.

Results

The cause of cervical cancer is a long-lasting infection with certain types of human papillomavirus (HPV) and without these viruses almost no cases of cervical cancer occur. A differentiation is made between types of virus that cause mainly warts (so-called low-risk types) and those that can trigger cancer (high-risk types). The first group includes HPV 6 and 11 and the second group includes types HPV 16 and 18, which are responsible for approximately 70?% of all cervical cancer cases. Since 2006 two vaccines have been available against the two types with the highest risk (HPV 16 and 18) and since 2015 there is a vaccine on the market that protects against five additional high-risk types (HPV 31, 33, 45, 52 and 58). This new nonavalent vaccine can prevent roughly 90?% of cervical cancers.

Conclusion

Regular participation in cervical cancer screening programs is still recommended.

     

Psychological impact of positive cervical cancer screening results among Japanese women

Background

While cervical cancer screening is useful for detecting and then treating the disease at an early stage, most women with screen-positive results are free from cervical cancer but nevertheless subject to the unnecessary worry entailed in receiving such results. The purpose of this study was to examine whether receiving a screen-positive result was actually related to psychological distress among Japanese women who underwent cervical cancer screening.

Methods

We conducted a questionnaire survey at health facilities in a semiurban city of Ibaraki prefecture, involving 1744 women who underwent cervical cancer screening and 72 who received screen-positive results and then underwent further testing. We used the K6 scale to assess their psychological distress (K6 score ≥5) and performed multiple logistic regression analyses to estimate the relative effect of receiving screen-positive results on psychological distress.

Results

Psychological distress was more prevalent among women with screen-positive results (OR 2.22; 95 % CI 1.32–3.74), while it was also related to history of mental health consultation (OR 2.26; 95 % CI 1.69–3.01) and marital status (OR 1.32; 95 % CI 1.02–1.70).

Conclusions

Receiving a positive cervical cancer screening result was associated with psychological distress. To alleviate this psychological impact, the current form of communicating the screening results should be reconsidered.

     

UBAP2L silencing inhibits cell proliferation and G2/M phase transition in breast cancer

Background

Ubiquitin-associated protein 2-like (UBAP2L) contains a ubiquitin-associated domain near its N-terminus, which has been demonstrated to be overexpressed in multiple tumors, including hepatocellular carcinoma and colorectal carcinoma but its role has not been well studied in breast cancer. Thus, this study was designed to evaluate whether UBAP2L can serve as a potential molecular target for breast cancer therapy.

Methods

The expression of UBAP2L was determined in breast cancer tissues and cell lines by Western blotting and Oncomine database mining. Then the expression of UBAP2L was silenced using RNA interference and the effects of UBAP2L knockdown on breast cancer cell proliferation and cell cycle progression by MTT and colony formation assay, and Flow cytometry, respectively.

Results

We found the expression of UBAP2L was significantly up-regulated in breast cancer tissues and cell lines. Knockdown of UBAP2L suppressed cell proliferation, impaired colony formation ability and induced cell cycle arrest at G2/M phase. At molecular levels, knockdown of UBAP2L increased p21 expression, but decreased the expression of CDK1 and Cyclin B1 in breast cancer cells.

Conclusion

Our findings suggest that UBAP2L plays an important role in breast cancer cell proliferation and might serve as a potential target for breast cancer treatment.

     

Trends of two HPV-associated cancers in Massachusetts: cervical and oropharyngeal cancer

Purpose

To understand trends in the incidence and mortality of two human papillomavirus (HPV)-associated cancers, cervical and oropharyngeal cancer, in Massachusetts.

Methods

From 2004 to 2014, the Massachusetts Cancer Registry recorded 3,996 incident cases of oropharyngeal cancer and 2,193 incident cases of cervical cancer. Mortality data were obtained from the Massachusetts Registry of Vital Records and Statistics from 2008 to 2014. Rates were age-standardized to the 2000 U.S. population and trends were assessed using joinpoint regression.

Results

While the incidence rate of cervical cancer (5.46 per 100,000) decreased by 2.41% annually (p?=?0.004), the incidence rate of oropharyngeal cancer among males (7.85 per 100,000) increased by 2.82% annually (p?=?0.0002). Mortality rates for both cancers decreased from 2008 to 2014 but were not statistically significant (cervical ??3.73% annually, p?=?0.29; oropharyngeal ??1.94% annually, p?=?0.44).

Conclusion

The rising incidence rate of oropharyngeal cancer in men and the decreasing, but relatively high, incidence rate of cervical cancer in women highlight the need for further screening and prevention by HPV vaccination in Massachusetts.

     

Bevacizumab for recurrent,persistent or advanced cervical cancer: reproducibility of GOG 240 study results in “real world” patients

Purpose

Bevacizumab is the only therapeutic target approved for patients with persistent, recurrent or advanced cervical cancer from a phase III study that combined with chemotherapy; it proves a significant increase in overall survival. To retrospectively assess the efficacy and safety of bevacizumab as the first-line treatment in patients from usual clinical practice with recurrent/persistent or advanced cervical cancer.

Patients and methods

Treatment consisted of cisplatin 50 mg/m² or carboplatin AUC 5 plus paclitaxel 175 mg/m² for 6–8 cycles and bevacizumab 15 mg/kg every 3 weeks up to progression or unacceptable toxicity. The endpoints were progression-free survival (PFS), overall survival (OS), response rates (RR) and toxicity.

Results

Twenty-seven patients were included from January 2014 to June 2017, with a median follow-up 10, 1 months. Eleven percent had recurrent/persistent disease and 89% had metastatic disease at diagnosis. The prior exposition to platinum was 70%. The median PFS and OS were 9, 6 and 21, 5 months, respectively. There was an increase of fistula formation (22%). All of them had pelvic and peritoneal disease at the beginning of treatment and previous treatment with chemoradiotherapy; non-incidence differences were found according to the type of platinum agent used. There were two treatment-related deaths, one from intestinal perforation and another from severe sepsis.

Conclusion

Finally, although our study does have certain limitations, we believe that it can provide useful information and encouraging evidence that the routine use of bevacizumab as part of first-line treatment of patients with advanced cervical cancer may be associated with outcomes comparable with those obtained in GOG240 study.

     

Early Cervical Cancer: Current Dilemmas of Staging and Surgery

Purpose of Review

Advances in cervical cancer screening and treatment have resulted in high cure rates in developed countries for early-stage disease. Current research focuses on minimizing morbidity and maximizing quality of life.

Recent Findings

Imaging has been disappointing in identifying small volume metastases. Sentinel lymph node biopsy represents a significant advantage with high sensitivity, low false negative rates, reduced morbidity, and equivalent survival in recent studies compared to pelvic lymphadenectomy. Non-radical surgical options are currently being investigated for early cervical cancer in a number of large prospective studies in patients at low risk for metastases.

Summary

Evidence suggests that sentinel lymph node biopsy and non-radical surgery are safe approaches for the staging and management of early cervical cancer in appropriately selected patients with the potential to significantly reduce treatment-related morbidity.