Inorganic arsenic promotes luminal to basal transition and metastasis of breast cancer.

Inorganic arsenic (iAs/As2 O32- ) is an environmental toxicant found in watersheds around the world including in densely populated areas. iAs is a class I carcinogen known to target the skin, lungs, bladder, and digestive organs, but its role as a primary breast carcinogen remains controversial. Here, we examined a different possibility: that exposure to iAs promotes the transition of well-differentiated epithelial breast cancer cells characterized by estrogen and progesterone receptor expression (ER+/PR+), to more basal phenotypes characterized by active proliferation, and propensity to metastasis in vivo. Our results indicate two clear phenotypic responses to low-level iAs that depend on the duration of the exposure. Short-term pulses of iAs activate ER signaling, consistent with its reported pseudo-estrogen activity, but longer-term, chronic treatments for over 6 months suppresses both ER and PR expression and signaling. In fact, washout of these chronically exposed cells for up to 1 month failed to fully reverse the transcriptional and phenotypic effects of prolonged treatments, indicating durable changes in cellular physiologic identity. RNA-seq studies found that chronic iAs drives the transition toward more basal phenotypes characterized by impaired hormone receptor signaling despite the conservation of estrogen receptor expression. Because treatments for breast cancer patients are largely designed based on the detection of hormone receptor expression, our results suggest greater scrutiny of ER+ cancers in patients exposed to iAs, because these tumors may spawn more aggressive phenotypes than unexposed ER+ tumors, in particular, basal subtypes that tend to develop therapy resistance and metastasis.

Risk factors for cervical HPV infection and genotypes distribution in HIV-infected South Brazilian women.

BACKGROUND: Human Papillomavirus (HPV) infection is particularly burdensome for women infected with human immunodeficiency virus (HIV), which increases their risk of developing cervical lesions and cancer (CC). We conducted a molecular study of the distribution of cervical HPV genotypes and the risk factors for this infection in HIV-infected Brazilian women. FINDINGS: Cervical and endocervical samples for Papanicolaou screening and HPV detection were collected from 178 HIV-infected women using highly active antiretroviral therapy (HAART) of Maringá city/Brazil. Risk factors were assessed using a standardized questionnaire, and the data regarding to HIV infection from medical records. HPV was detected by polymerase chain reaction (PCR), and genotyping using PCR-restriction fragment length polymorphism analysis. HIV infection was well controlled, but women with a current CD4+ T lymphocyte count between 200-350 cells/mm3 (37.6%) had a two-fold greater risk of HPV infection than those with > 350 cells/mm3 (26.4%). HPV was associated with parity ≥3, hormonal contraceptive use and current smoker. HPV infection occurred with high frequency (46.6%) but a low frequency of cervical abnormalities was detected (7.30%), mainly low-grade squamous intraephitelial cervical lesions (LSIL) (84.6%). A high frequency of multiple HPV infections was detected (23.0%), and the most frequent HPV genotype was HPV-72 (6.7%), followed by -16, -31 and -51 (6.14% each). CONCLUSIONS: We showed that HAART use does not protect HIV-infected women from HPV, but appear to exert some protection against cervical lesions development. This study provides other important information about risk factors and cervical HPV in HIV-infected women, which can contribute to planning protocols.

Simultaneous detection of seven sexually transmitted agents in human immunodeficiency virus-infected Brazilian women by multiplex polymerase chain reaction.

We determined the prevalence of seven clinically important pathogens that cause sexually transmitted infections (STIs) (Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, herpes simplex virus 1 [HSV-1], HSV-2, and Treponema pallidum), by using a multiplex polymerase chain reaction (M-PCR) in samples from Brazilian woman infected with human immunodeficiency virus 1 (HIV-1) and uninfected Brazilian women (controls). The M-PCR assay identified all STIs tested for and surprisingly, occurred association between the control and STIs. This association was probably caused by excellent HIV infection control and regular monitoring in these women established by public health strategies in Brazil to combat HIV/acquired immunodeficiency syndrome. Studies using this M-PCR in different populations may help to better elucidate the roles of STIs in several conditions.

Molecular detection of HPV and Chlamydia trachomatis infections in Brazilian women with abnormal cervical cytology.

The question of whether Chlamydia trachomatis (Ct) is a cofactor for human Papillomavirus (HPV) in cervical carcinogenesis is still controversial. We conducted a molecular detection study of both infections in 622 Brazilian women, including 252 women with different grades of abnormal cervical cytology and cervical cancer (CC; cases) and 370 women with normal cytology (controls). Although Ct infection did not seem related to CC carcinogenicity, women with abnormal cytology had a significant high rate of Ct infection. Therefore, it is important to adopt protocols for diagnosis and treatment of this bacterium in conjunction with screening for CC in this population.