Prévention du cancer du col utérin : enjeux et perspectives de la vaccination antipapillomavirus

Therapeutic cancer vaccines: From biological mechanisms and engineering to ongoing clinical trials

Therapeutic vaccines are currently at the forefront of medical innovation. Various endeavors have been made to develop more consolidated approaches to producing nucleic acid-based vaccines, both DNA and mRNA vaccines. These innovations have continued to propel therapeutic platforms forward, especially for mRNA vaccines, after the successes that drove emergency FDA approval of two mRNA vaccines against SARS-CoV-2. These vaccines use modified mRNAs and lipid nanoparticles to improve stability, antigen translation, and delivery by evading innate immune activation. Simple alterations of mRNA structure- such as non-replicating, modified, or self-amplifying mRNAs- can provide flexibility for future vaccine development. For protein vaccines, the use of long synthetic peptides of tumor antigens instead of short peptides has further enhanced antigen delivery success and peptide stability. Efforts to identify and target neoantigens instead of antigens shared between tumor cells and normal cells have also improved protein-based vaccines. Other approaches use inactivated patient-derived tumor cells to elicit immune responses, or purified tumor antigens are given to patient-derived dendritic cells that are activated in vitro prior to reinjection. This review will discuss recent developments in therapeutic cancer vaccines such as, mode of action and engineering new types of anticancer vaccines, in order to summarize the latest preclinical and clinical data for further discussion of ongoing clinical endeavors in the field.

Awareness and knowledge regarding of cervical cancer, Pap smear screening and human papillomavirus infection in Gabonese women

BACKGROUND

Cervical cancer is the commonest cancer and the leading cause of cancer mortality in women in Gabon. The age-standardized incidence of cervical cancer is 19.9 per 100 000 women and the mortality rate is 8.4 per 100 000. Various international studies have identified the lack of awareness and knowledge about cervical cancer as barriers to use preventive methods. This article assesses the awareness and knowledge about cervical cancer, Pap smear testing and its use and HPV among women living in Libreville, Gabon.

METHODS

This study was conducted in October 2014 in Libreville. A total of 452 women aged 16 years and above were recruited from different town locations. Logistic regression analysis was used to identify the effect of demographic characteristics on the level of knowledge about cervical cancer, Pap smear testing and HPV. Odds ratio and 95% confidence intervals were used to identify the strength of association. Associations were considered statistically significant at p < 0.05.

RESULTS

Of all the women interviewed, 91.6% (414/452) had heard about cervical cancer and only 27.9% (126/452) had heard of Pap smear test. Of these 126 women, only 65.1% (82/126) had done cervical cancer screening and 68.3% (56/82) on the suggestion of a doctor. The most common reason for not undergoing Pap smear testing was neglect (50%, 22/44) followed by lack of financial resources (13.6%, 6/44), fear of discovering a serious disease (13.6%, 6/44) and deeming it unimportant (13.6%, 6/44). Only 8% (40/452) of the participants had heard about HPV and their knowledge of HPV was fair. There is a very poor level of knowledge about cervical cancer among Gabonese women.

CONCLUSION

This study demonstrates a very low level of knowledge about cervical cancer, Pap smear testing and HPV in a sample of Gabonese women. There is a critical need for Gabonese women to be informed about cervical cancer and the Pap smear test to improve the use of this preventive method. The implication of health staff and Gabonese media should be included as a centerpiece in the effort to inform the population in order to reduce the burden of cervical cancer in Gabon and save women lives.

Electrospun nanofibrous mats containing quaternized chitosan and polylactide with in vitro antitumor activity against HeLa cells

Nanofibrous materials containing the antitumor drug doxorubicin hydrochloride (DOX) were easily prepared using a one-step method by electrospinning of DOX/poly(L-lactide-co-D,L-lactide) (coPLA) and DOX/quaternized chitosan (QCh)/coPLA solutions. The pristine and DOX-containing mats were characterized by ATR-FTIR and X-ray photoelectron spectroscopy (XPS). The release rate of DOX from the prepared fibers increased with the increase in DOX content. The DOX release process was diffusion-controlled. MTT cell viability studies revealed that incorporation of DOX and QCh in the nanofibrous mats led to a significant reduction in the HeLa cells viability. It was found, that the antitumor efficacy of the DOX-containing mats at 6 h was higher than that of the free DOX. SEM, TEM, and fluorescence microscopic observations confirmed that the antitumor effect of QCh-based and DOX-containing fibrous mats was mainly due to induction of apoptosis in the HeLa cells.

In vitro ultramorphological assessment of apoptosis induced by zerumbone on (HeLa)

Zerumbone (ZER), a potential anticancer compound, isolated from the fresh rhizomes of Zingiber zerumbet. In this investigation, the cytotoxic properties of ZER were evaluated, on cancer cells of human cervix (HeLa), breast and ovary, and normal cells of Chinese Hamster ovary, using MTT assay. Apoptogenic effects of ZER on HeLa were studied using fluorescence microscopy (AO/PI double staining), scanning and transmission electron microscopy (SEM and TEM), and colorimetric assay of the apoptosis promoter enzyme, caspase-3. The results of MTT assay showed that ZER has less effect on normal cells compared to cancer cells. The lowest IC(50) of ZER was observed on HeLa cells. Cytological observations showed nuclear and chromatin condensation, cell shrinkage, multinucleation, abnormalities of mitochondrial cristae, membrane blebbing, holes, cytoplasmic extrusions and formation of apoptotic bodies as confirmed collectively by double staining of AO/PI, SEM and TEM. Statistical analysis (two-tailed t-test) of differential counting of 200 cells under fluorescence microscope revealed significant difference in apoptotic cells populations between treated and untreated HeLa cells. In addition, ZER has increased the cellular level of caspase-3 on the treated HeLa cells. It could be concluded that ZER was able to produce distinctive morphological features of cell death that corresponds to apoptosis.

In vitro ultramorphological assessment of apoptosis induced by zerumbone on (HeLa)

Zerumbone (ZER), a potential anticancer compound, isolated from the fresh rhizomes of Zingiber zerumbet. In this investigation, the cytotoxic properties of ZER were evaluated, on cancer cells of human cervix (HeLa), breast and ovary, and normal cells of Chinese Hamster ovary, using MTT assay. Apoptogenic effects of ZER on HeLa were studied using fluorescence microscopy (AO/PI double staining), scanning and transmission electron microscopy (SEM and TEM), and colorimetric assay of the apoptosis promoter enzyme, caspase-3. The results of MTT assay showed that ZER has less effect on normal cells compared to cancer cells. The lowest IC₅₀ of ZER was observed on HeLa cells. Cytological observations showed nuclear and chromatin condensation, cell shrinkage, multinucleation, abnormalities of mitochondrial cristae, membrane blebbing, holes, cytoplasmic extrusions and formation of apoptotic bodies as confirmed collectively by double staining of AO/PI, SEM and TEM. Statistical analysis (two-tailed t-test) of differential counting of 200 cells under fluorescence microscope revealed significant difference in apoptotic cells populations between treated and untreated HeLa cells. In addition, ZER has increased the cellular level of caspase-3 on the treated HeLa cells. It could be concluded that ZER was able to produce distinctive morphological features of cell death that corresponds to apoptosis.

La contraception des adolescentes en France en 2007

The two main objectives of adolescence contraception are the eviction of involuntary pregnancies and the prevention of sexually transmitted infections. In France, in spite of our rich contraceptive arsenal and a widely spread information, the rate of voluntary termination of pregnancy keeps growing among the teenagers population--and this, probably because the gap between theoretical effectiveness and practice of contraception is particularly wide among the young people. Every contraceptive means can be used by teenagers; the best option being, it seems, the "double DUTCH", which consists of concomitant use of condoms and hormonal contraception. Most often, the consultation for contraception is the first gynaecological consultation. That is the reason why it is usually stressful for teenagers who dread undergoing a gynaecological examination. If this examination is not necessary for most of young patients, it is essential to create a trustful relationship and to make explicit the several contraceptive methods. During this consultation it is interesting to look for common teenage troubles like addiction to smoking and eating disorders. For any prescription of hormonal contraception, it is important to explain the benefits and the possible side effects, to stress the observance and to tell the teenager about the recommendations in case of forgetting. Concerning condom - the only efficient way of preventing sexually transmitted infections--, it is useful to talk about it in concrete and straightforward terms, to show its handling and to inform about risks of tearing. With this state of mind, an emergency contraception can be prescribed straightaway in order to make its use easier. Also, without any moralizing speech, the need for maturity must be emphasized as well as taking care of one's body with the aim of avoiding a premature pregnancy or any sexually transmitted infection. This consultation must be coupled with a close follow-up, availability and mutual confidence which are the main elements vouching for a good observance and consequently an efficient contraception.