A new phenyl alkyl ester and a new combretin triterpene derivative from Combretum fragrans F. Hoffm (Combretaceae) and antiproliferative activity

This work concerns the isolation and structure elucidation of compounds obtained from the extract of leaves and stem bark of Combretum fragrans F. Hoffm. Both extracts and some isolated compounds were tested for antiproliferative activity on glioblastoma (U87MG and C6 cells) and prostate (PC-3 cells) cancer cell lines using XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxyanilide inner salt) assay. The dichloromethane/methanol (1:1) extract of the leaves led to the isolation of two new compounds such as fragransinate (1) and combretin C (2), alongside five known compounds such as combretin A (3), belamcanidin (4), cirsilineol (5), velutin (6), and a mixture of β-sitosterol-3-O-β-d-glucopyranoside (10a) and stigmasterol-3-O-β-d-glucopyranoside (10b), whereas the methanol extract of the stem bark led to the isolation of three known compounds betulinic acid (7), bellericagenin B (8), and a mixture of β-sitosterol (9a) and stigmasterol (9b). The structure of compounds was elucidated by nuclear magnetic resonance and mass spectrometry data. The methanol extract of the stem bark showed a powerful antiproliferative activity on all tested cells, as well as the extract of leaves which also showed important cytotoxicity effect. Compound (3) showed good antiproliferative activity particularly on U87MG and PC-3 cells, whereas compound (5) exhibits moderated activity. Compounds (2) and (8) were not active on all tested cells.

Influence of HIV infection on the distribution of high-risk HPV types among women with cervical precancerous lesions in Yaounde, Cameroon

OBJECTIVES

To characterize high-risk HPV types associated with cervical precancerous lesions in women living in Yaounde, Cameroon, and to determine their distribution with HIV status.

METHODS

Women with abnormal pap smears recorded from February 2015 to May 2019 at Saint Martin de Porres' Health Centre, Yaounde, Cameroon, were recruited in this study after obtaining informed consent. Pap smears were collected and re-examined. Human immunodeficiency virus (HIV) serology was determined. HPV16, 18, 33, and 45 were assessed using standard PCR.

RESULTS

All included participants (370) were HPV-positive and had either low grade squamous intraepithelial lesions (67.03%) or high grade squamous intraepithelial lesions (31.35%). They were subdivided into HIV-positive (N =102) and HIV-negative (N =268). In the HIV-negative subgroup, we observed 66.04% HPV16-positve, 41.79% HPV18-positve, 21.27% HPV33-positve and 8.21% HPV45-positve. In the HIV-positive subgroup, we observed 22.55% HPV16-positve, 5.88% HPV18-positve, 75.49% HPV33-positve, and 49.02% HPV45-positve. Married HIV-positive participants (47.14 ± 1.19) were older than both their single counterparts (34.94±1.22, P = 0.0008) and HIV-negative participants (41.43 ± 0.79, P = 0.0001). Single HIV-positive women reported higher numbers of miscarriages (P = 0.0023), and had later first sexual intercourse than HIV-negative (P = 0.0079) women.

CONCLUSION

Our study suggested differential expressions in high-risk HPV types with HIV status and cervical precancerous lesions and warrants more extensive studies.

Cervical Cancer Awareness and Detection of Precancerous Lesions at Two District Health Centres in the West Region of Cameroon

Background: Due to the late diagnosis, resulting partly from the absence of national screening programs, Cervical cancer is a public health concern for women in Sub-Saharan Africa, where 34 over 100,000 are diagnosed with cervical cancer and 23 over 100,000 die yearly. We evaluated the knowledge and practices of the female population towards the prevention of cervical cancer in the city of Bafoussam, West Cameroon, considering that poor awareness about the disease and its prevention drives its progression in Africa.Methods: 228 women were recruited during a cross-sectional study with simple random selection of participants in two District Health Centres in Bafoussam from February to August 2017. They were administered a questionnaire aimed at asserting their knowledge about cervical cancer, risk factors and prevention. Subsequently, cervicovaginal smears were screened and gynaecological signs were assessed. Data analysis was done using Epi info version 7.2.2.6. with Chi 2 test application.Statistical significance was set at p < 0.05.Results: The most represented age group was [25-35] (50.88%). Only 89 participants (39.04%) had heard about cervical cancer, 63 (27.63%) had heard about risk factors with only 13 (5.70%) able to name at least one risk factor. Moreover, 72 participants (31.58%) had heard about cervical screening test, 48 (21.05%) were aware about the existence of means of prevention, and only 6 (2.63%) had heard about human papillomavirus (HPV) relationship to cervical cancer or HPV vaccine. An incidence of 07.63% was obtained. The most common reason reported for not attending cervical cancer screening was ignorance (68.92%). Conclusions: Our data suggest that there is a real need for raising the awareness about cervical cancer and its prevention in the western region of Cameroon.

Newtonoate as an active principle of Newtonia griffoniana for anxiolytic activity in Swiss mice

BACKGROUND

Newtonia griffoniana (Mimosaceae) is a Central African rain forest tree, whose bark extracts are used in Cameroonian folk medicine for the treatment of anxiety and sleep disorders.

METHODS

We evaluated the anxiolytic effects of N. griffoniana stem bark methanol extract and its major isolated constituent 2,3,4-trihydroxybutylpentatriacontanoate (newtonoate) on the elevated plus maze.

RESULTS

Significant increases in the percentage of entries into open arms were induced by both N. griffoniana extract (100 and 150 mg/kg BW; p<0.01) and newtonoate (doses of 3 and 15 mg/kg BW; p<0.05). Conversely, decreases in the percentage of entries into closed arms were observed at the same doses. In addition, N. griffoniana methanol extract (100 mg/kg) and the isolated newtonoate (30 mg/kg) induced significant (p<0.01 and p<0.05, respectively) increases in the time spent in the open arms, while inducing a decrease in the time spent in the closed arms. Newtonoate treatment also decreased head dipping number at doses of 3 and 15 mg/kg, while N. griffoniana methanol extract induced the same effect at 200 mg/kg.

CONCLUSIONS

These results suggest that N. griffoniana bark extract has anxiolytic properties, which justify its use in folk medicine. Such effects are at least partly mediated by newtonoate.

Role of epigenetic in cancer biology, in hematologic malignancies and in anticancer therapy

Major epigenetic changes are associated with carcinogenesis, including aberrant DNA methylations and post-translational modifications of histone. Indeed evidence accumulated in recent years indicates that inactivating DNA hypermethylation preferentially targets the subset of polycomb group (PcG) genes that are regulators of developmental processes. Conversely, activating DNA hypomethylation targets oncogenic signaling pathway genes, but outcomes of both events lead in the overexpression of oncogenic signaling pathways that contribute to the stem-like state of cancer cells. On the basis of recent evidence from population-basedclinical and experimental studies, we hypothesize that factors associated with risk for developing a hematologic malignancy (HM), such as metabolic syndrome and chronic inflammation, may trigger epigenetic mechanisms to increase the transcriptional expression of oncogenes and activate oncogenic signaling pathways. Signaling pathways associated with such risk factors include but are not limited to pro-inflammatory nuclear factor κB (NF-κB) and mitogenic, growth, and survival Janus kinase (JAK) intracellular non-receptor tyrosine kinase-triggered pathways. The latter includes signaling pathways such as transducer and activator of transcription (STAT), Ras GTPases/mitogen-activated protein kinases (MAPKs)/extracellular signal-related kinases (ERKs), phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR), and β-catenin pathways. Recent findings on epigenetic mechanisms at work in the biology of cancer and in HMs and their importance in the etiology and pathogenesis of these diseases are herein summarized and discussed. Furthermore, the role of epigenetic processes in the determination of biological identity, the consequences for interindividual variability in disease clinical profile, and the potential of epigenetic drugs in HMs are also considered.

Breast cancer awareness and screening practice amongst health personnel and general population of the littoral region of Cameroon

INTRODUCTION

Late diagnosis has been observed as the hallmark of breast cancer in Cameroonian women where over 70% of patients report with either stage III or IV of the disease, with high mortality and dire socioeconomic consequences. The present study was undertaken to assess the awareness of breast cancer, warning signs and screening methods among Health professionals and general population of Douala.

METHODS

Participants included in this study were health practitioners and women randomly selected and enrolled in six health facilities in the city of Douala, Littoral Region, Cameroon. A self-administered questionnaire was designed for each group and aimed at assessing their knowledge about breast cancer, warning signs and screening practices. Then, 616 women underwent breast palpation, followed by fine needle aspiration (FNA) when a nodule was found.

RESULTS

Out of a total of 737 participants (121 health personnel and 616 women) interviewed, a majority (96.3%) were aware of the disease with the main source of information being the hospital (76.0%), media (47.1%) and vocational training schools (45.4%) for health personnel; medias (39.9%), health professionals (26.1%) and their entourage (21.9%) for the population. Health workforce presented suitable awareness of the risk factors for breast cancer and its clinical signs even though 37.1% of them had misconceptions and myth-based ideas on the origin of the disease. Both the population and health personnel were aware of the possibility of early screening for breast cancer and cited breast self-examination, clinical breast examination and mammography as screening techniques. Nonetheless, screening practice amongst all women is very poor and mainly due to ignorance, high cost of mammography, together with a lack of mastery of the BSE technique and the fear of actually discovering signs of the disease.

CONCLUSION

Our findings show lack of awareness and low practice of breast cancer screening amongst women in Douala and highlight the need to raise awareness and provide the right information to the public for early detection of breast cancer.

Anticancer Activity of Combretum fragrans F. Hoffm on Glioblastoma and Prostate Cancer Cell Lines

BACKGROUND

Cancer incidence has been growing in an alarming rate worldwide and new therapeutics are needed, particularly for intractable and chemoresistant cases. We evaluated the cytotoxic effects of Combretum fragrans F. Hoffm (Combretaceae) on glioblastoma (U87MG and C6) and prostate (PC-3) cancer cell lines.

METHODS

The cytotoxic effect of the methanolic extract of the stem bark of Combretum fragrans was assessed using XTT (2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide) test. Expressions of Akt and ERK1/2 were determined using Western blot technique, while Caspase-3/7 kits were used to evaluate caspase-3/7 activity.

RESULTS

C. fragrans extract inhibited the proliferation of U87 (IC50 = 20.13 µg/mL), C6 (IC50 = 12.17 µg/mL), and PC-3 (IC50 = 11.50 µg/mL) cells. Treatment with the extract resulted in lower levels (p < 0.001) of phospho-ERK1/2 and phospho-Akt in U87 cells, and instead, higher levels of phospho-ERK1/2 (p < 0.001) in C6 and PC-3 cells. An increase in caspase-3/7 activity was observed, mainly after 24 hours of treatment, indicating the activation of apoptotic processes.

CONCLUSION

Altogether, these results suggest that C. fragrans have potent anticancer properties. This plant should be further investigated for developing new anticancer drugs.

Assessment of breast cancer awareness and detection of asymptomatic cases in Ngaoundere, Adamawa region of Cameroon

INTRODUCTION

In Cameroon and most African countries, breast cancer (BC) is mainly diagnosed at an advanced stage, leading to worse prognosis and disease consequences. This is partly due to the delayed presentation of patients, which constitutes a significant barrier to the effective management of the disease. The aim of this descriptive, cross-sectional study is to identify the level of awareness of breast cancer and screening practice among women and health professionals in the city of Ngaoundere, Cameroon.

METHODS

Women and medical personnel were randomly recruited in two health institutions in the Adamawa region, Cameroon: the Ngaoundere Regional Hospital and the Ngaoundere Protestant Hospital. Two different questionnaires were prepared. The first was to collect sociodemographic data and assess participants' awareness of BC and related symptoms. The second was to collect information from the recommended screening methods for early detection of cases, including the frequency of screening practice among women and the daily practice of medical personnel.

RESULTS

Out of the women surveyed, 88.05 % have heard of breast cancer, but the majority were unaware of its clinical signs (47.1 %) and the means of treatment (22 %). In the studied population, 66.4 % were aware of the screening, but the practice was very low, as only 1.1 % of women had ever undergone screening by mammography and only 6 % often practiced breast self-examination (BSE). The levels of screening knowledge and practice were significantly associated with the level of education and employment status (P = 0.0001). In the group of 94 health personnel surveyed, 68.1 % had no knowledge of breast cancer screening methods, and only 30 % performed breast cancer screening in their daily practice. The practice of BSE during the study allowed a detection of 2 % of screened women with some suspicious clinical signs.

CONCLUSION

This study revealed a lack of knowledge about BC and its screening methods and practice among women and health personnel in Ngaoundere. This lack of knowledge constitutes a significant barrier to early diagnosis of BC. There is a need to raise awareness and provide education and information about BC screening.