Cervical Precancerous Lesions and Associated Factors Among Women Screened in Two Hospitals in the City of Douala, Cameroon.

INTRODUCTION: Cervical cancer remains the second leading cause of death among women in Cameroon despite the new strategies put in place. This study was conducted in order to determine the prevalence of precancerous cervical lesions and its associated factors in Douala (Cameroon). METHODS:  A cross-sectional study was conducted over a period of nine months in two hospitals of the city of Douala, Cameroon (Laquintinie Hospital and Gyneco-Ostetric and Pediatric Hospital). Cervico-vaginal and endocervical samples were taken from women attending the above-mentioned hospitals in order to identify and characterize precancerous lesions by cytological examination and to genotype for human papillomavirus (HPV) using the Abbott RealTime High-Risk (HR) HPV kit. Data of sociodemographic characteristics, clinical history, and knowledge about cervical cancer were collected using a questionnaire. RESULTS: Of the 196 women included in this study, 17% had precancerous lesions, including 1.53% for atypical glandular cells (AGC), 4.53% for atypical squamous cells (ASC), 4.53% for low-grade squamous intraepithelial lesion (LSIL), 5.61% for high-grade squamous intraepithelial lesion (HSIL), 0.51% for atypical squamous cells of undetermined significance (ASC-US), and 0.51% for atypical squamous cells cannot exclude HSIL (ASC-H). In addition, the prevalence of HPV infection was 18%, of which 2% was for HPV 16, 2% for HPV 18, and 14% for undetermined HPV. A positive association was recorded between the occurrence of precancerous lesions and HPV infection (P=0.01), age, and school level. Moreover, the occurrence of precancerous lesions was positively associated with the participants' level of knowledge (P=0.01). DISCUSSION: Precancerous lesions were predominantly HSIL, and the factor most associated with these lesions was HPV infection. CONCLUSION: This study demonstrates that diagnosis is made at a relatively late stage due to a low level of knowledge about cervical cancer in the population.

Euphol from Tapinanthus sp. Induces Apoptosis and Affects Signaling Proteins in Glioblastoma and Prostate Cancer Cells

BACKGROUND: Plants play an important role in cancer therapy. They are source of natural molecules which can induce apoptosis in cancer cells by affecting molecular mechanisms implicated in cancer progression. The MAP Kinase/ERK1/2 and PI3K/AKT signaling pathways are two classical signaling pathways implicated in cancer progression and constitute therapeutic targets against cancer. This study aimed to evaluate the effect of euphol on MAP Kinase/ERK1/2 and PI3K/AKT signaling pathways in glioblastoma and prostate cancer cells. Euphol is a tetracyclique triterpene alcohol isolated from Tapinanthus sp. which is a hemi parasitic plant belonging to Loranthaceae family. METHODS: Plant powder was extracted by maceration and euphol was isolated and described using respectively column chromatography separation on silica gel and spectroscopic data. Cytotoxic effect of euphol was evaluated using XTT assay and its effect on MAP Kinase/ERK1/2 and PI3K/AKT protein expression was investigated by Western immunoblot analysis. Apotosis was analyzed by evaluating caspase-3/7 activity. RESULTS: Our investigations demonstrated that this compound has an important cytotoxic effect on C6 and U87 MG glioblastoma (GBM) cells and PC-3 prostate cancer cells. Furthermore, euphol-induced apoptosis revealed by elevated caspase 3/7 activity, was correlated with a significant inhibition of MAP kinase/Erk 1/2 and PI3K/Akt signaling pathway in glioblastoma U87 MG cells. The reverse effect was observed in C6 glioblastoma cells, where apoptosis was correlated with a long-lasting activation of Erk 1/2.  In PC-3 cells, euphol had no or limited effect on Erk 1/2 and Akt activity. CONCLUSION: These results indicate that euphol induces cell death in glioblastoma and prostate cancer cells and regulates significantly Erk1/2 and Akt activity in glioblastoma cells.

Insulin-like growth factor-1 signaling in the tumor microenvironment: Carcinogenesis, cancer drug resistance, and therapeutic potential.

The tumor microenvironment fuels tumorigenesis and induces the development of resistance to anticancer drugs. A growing number of reports support that the tumor microenvironment mediates these deleterious effects partly by overexpressing insulin-like growth factor 1 (IGF-1). IGF-1 is known for its role to support cancer progression and metastasis through the promotion of neovascularization in transforming tissues, and the promotion of the proliferation, maintenance and migration of malignant cells. Anti-IGF therapies showed potent anticancer effects and the ability to suppress cancer resistance to various chemotherapy drugs in in vivo and in vitro preclinical studies. However, high toxicity and resistance to these agents are increasingly being reported in clinical trials. We review data supporting the notion that tumor microenvironment mediates tumorigenesis partly through IGF-1 signaling pathway. We also discuss the therapeutic potential of IGF-1 receptor targeting, with special emphasis on the ability of IGF-R silencing to overcome chemotherapy drug resistance, as well as the challenges for clinical use of anti-IGF-1R therapies.

A new flavonoid glycoside from Tapinanthus sp. (Loranthaceae) and evaluation of anticancer activity of extract and some isolated compounds.

The present work describes the isolation and anticancer activity of Tapinanthus sp. which is a hemi parasitic plant harvested on Combretum glutinosum, the host plant. Phytochemical study afforded a new flavonoid glycoside, tapinantoside (1) isolated for the first time from natural source, alongside six known compounds (2-7). Structure of compounds were elucidated by extensive spectroscopic analyses including 1 D and 2 D NMR, mass spectrometry and by comparison with literature data. The anticancer activity of extract and some isolated compounds were evaluated on glioblastoma (U87MG, C6) and prostate (PC-3) cancer cells. The methanol leaves extract showed good anticancer activity against U87 (IC50 = 21.40 µg/mL) and PC-3 cells (IC50 = 10.26 µg/mL). Compound 3 powerfully inhibits the proliferation of C6 (IC50 = 38.84 µM) and PC-3 cells (IC50 = 21.33 µM), while its effect was moderated on U87MG cells. Compound 1 and 7 were not active on all tested cancer cell lines.

Prevalence of precancerous cervical lesions and high-risk human papillomavirus types in Yaounde, Cameroon.

INTRODUCTION: Various Human papillomavirus (HPV) types cause cervical cancer, and represent the primary cause of cancer death in Africa and the second cause of most common cancers in Cameroon. Herein, we determined the prevalence of high-risk HPV types in women and associated cervical cytologic abnormalities in Yaounde, Cameroon. METHODOLOGY: A cross-sectional study targeting HPV-positive women aged 20 and over was conducted between March and June 2020 at the Saint Martin de Porres' Health Centre in Yaounde. HPV tests were performed by PCR for detection of HPVs 16, 18, 33, and 45. The test was performed on 616 women using exfoliated cell specimens; then, we processed on cytological diagnosis with Pap smears on HPV positive specimens. RESULTS: The HPV types tested were detected in 137 participants, of which 38.7% with multiple HPV infections, and the remaining part with single HPV infections of type HPV 16 (28.5%), HPV 18 (17.5%), HPV 33 (10.2%), and HPV 45 (5.1%). Cervical cytologic abnormalities were found in 69.34% of participants including: LSIL (49.63%), HSIL (15.32%), ASC-US (3.66%) and AGC (0.73%). Co-infections with HPV 16 and HPV 18 were significantly associated with HSIL (p = 0.001) lesions, while HPV 45 was more common in participants with normal cytology (p = 0.001). Cervical lesion occurrence was significantly associated with the number of sexual partners (p = 0.02) and history of oral contraceptive pill use (p = 0.001). CONCLUSIONS: Our results suggest that HPV 16 and 18 are predominant in Yaounde, and are associated with more severe precancerous lesions.

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.

Awareness of Breast Cancer Screening among the Medical and General Population of the North Region of Cameroon.

Breast cancer has become a real public health problem in Cameroon, particularly in rural areas due to late diagnosis, resulting partly from the absence of national screening programs. This work is aimed at assessing breast cancer awareness in the North Region of Cameroon. Participants were selected in six health centers surrounding the rural area of Garoua, North Region, Cameroon, and administered a questionnaire aimed at assessing their awareness about breast cancer risk factors and screening. Out of the 475 women (including 37 medical personnel) interviewed, 45.5% attended at least secondary school; 91.3% were aware of the disease with the main sources of information from those around them (64.8%), media (46.5%), and health professionals in health facilities (42.7%). 23.3% had misconceptions and myth-based ideas on the origin of the disease. Ignorance was the main reason preventing the performance of breast self-examination, and the high cost prevents individuals from going for mammography. The highest awareness rate was observed in employed women with higher level of education. Our study highlights the need to raise awareness among the populations in North Region, Cameroon, about the risk factors and clinical signs of breast cancer and the importance of screening practice for early diagnosis 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.

Emerging data supporting stromal cell therapeutic potential in cancer: reprogramming stromal cells of the tumor microenvironment for anti-cancer effects.

After more than a decade of controversy on the role of stromal cells in the tumor microenvironment, the emerging data shed light on pro-tumorigenic and potential anti-cancer factors, as well as on the roots of the discrepancies. We discuss the pro-tumorigenic effects of stromal cells, considering the effects of tumor drivers like hypoxia and tumor stiffness on these cells, as well as stromal cell-mediated adiposity and immunosuppression in the tumor microenvironment, and cancer initiating cells' cellular senescence and adaptive metabolism. We summarize the emerging data supporting stromal cell therapeutic potential in cancer, discuss the possibility to reprogram stromal cells of the tumor microenvironment for anti-cancer effects, and explore some causes of discrepancies on the roles of stromal cells in cancer in the available literature.

Developmental pathways associated with cancer metastasis: Notch, Wnt, and Hedgehog.

Master developmental pathways, such as Notch, Wnt, and Hedgehog, are signaling systems that control proliferation, cell death, motility, migration, and stemness. These systems are not only commonly activated in many solid tumors, where they drive or contribute to cancer initiation, but also in primary and metastatic tumor development. The reactivation of developmental pathways in cancer stroma favors the development of cancer stem cells and allows their maintenance, indicating these signaling pathways as particularly attractive targets for efficient anticancer therapies, especially in advanced primary tumors and metastatic cancers. Metastasis is the worst feature of cancer development. This feature results from a cascade of events emerging from the hijacking of epithelial-mesenchymal transition, angiogenesis, migration, and invasion by transforming cells and is associated with poor survival, drug resistance, and tumor relapse. In the present review, we summarize and discuss experimental data suggesting pivotal roles for developmental pathways in cancer development and metastasis, considering the therapeutic potential. Emerging targeted antimetastatic therapies based on Notch, Wnt, and Hedgehog pathways are also discussed.

Mesenchymal stromal cells' role in tumor microenvironment: involvement of signaling pathways.

Mesenchymal stromal cells (MSCs) are adult multipotent stem cells residing as pericytes in various tissues and organs where they can differentiate into specialized cells to replace dying cells and damaged tissues. These cells are commonly found at injury sites and in tumors that are known to behave like " wounds that do not heal." In this article, we discuss the mechanisms of MSCs in migrating, homing, and repairing injured tissues. We also review a number of reports showing that tumor microenvironment triggers plasticity mechanisms in MSCs to induce malignant neoplastic tissue formation, maintenance, and chemoresistance, as well as tumor growth. The antitumor properties and therapeutic potential of MSCs are also discussed.