Laboratory of DNA Polymorphisms and Immunology, Department of Pathological Sciences, Biological Sciences Center, Londrina State University, Londrina, PR 86057-970, Brazil.
Department of General Biology, Biological Sciences Center, Londrina State University, Londrina, PR 86057-970, Brazil.
Int J Environ Res Public Health. 2020 Dec 18;17(24):9496. doi: 10.3390/ijerph17249496.
Breast cancer (BC) is a complex disease in which susceptibility and clinical course depend on multiple factors. Evidence suggests that a mouse mammary tumor virus (MMTV)-homolog may be present in human BCs; however, little is known about its clinical implications. MMTV-like nucleotide-sequence was searched in tumor and tumor-adjacent tissues from 217 Brazilian BC patients through nested-PCR and confirmed through PCR-sequencing. Blood samples were also tested for patients with MMTV-like gene-positive tumors. Correlations with clinicopathological parameters were evaluated. MMTV-like sequence was detected in tumor and tumor-adjacent tissue samples from 41/217 and 30/196 patients, respectively. In blood, MMTV-like was detected in 17/32 patients. In Luminal-B tumors, MMTV-like in tumor tissue was negatively correlated with tumor size and disease stage, whereas in HER2 tumors it anti-correlated with lymph node metastasis (LNM) and disease stage. Considering blood, MMTV-like gene positivity negatively correlated with age in general BC, while in Luminal-A tumors it positively correlated with Ki67 but negatively correlated with age and LNM. The associations with decreased LNM frequency were independent of other prognostic factors. MMTV-like positivity is associated with better prognostic parameters in BC subtypes, which might be explainable by its anti-metastatic potential and by putative activation of immune milieu.
乳腺癌（BC）是一种复杂的疾病，其易感性和临床病程取决于多种因素。有证据表明，人类乳腺癌中可能存在一种鼠乳腺肿瘤病毒（MMTV）同源物；然而，其临床意义知之甚少。通过巢式 PCR 法在 217 例巴西乳腺癌患者的肿瘤和肿瘤旁组织中搜索 MMTV 样核苷酸序列，并通过 PCR 测序进行确认。还对有 MMTV 样基因阳性肿瘤的患者的血液样本进行了检测。评估了与临床病理参数的相关性。在 217 例患者的肿瘤和肿瘤旁组织样本中分别检测到 41/217 和 30/196 例 MMTV 样序列。在血液中，在 17/32 例患者中检测到 MMTV 样序列。在 Luminal-B 型肿瘤中，肿瘤组织中的 MMTV 样与肿瘤大小和疾病分期呈负相关，而在 HER2 型肿瘤中，它与淋巴结转移（LNM）和疾病分期呈负相关。考虑到血液，MMTV 样基因阳性与一般 BC 的年龄呈负相关，而在 Luminal-A 型肿瘤中，它与 Ki67 呈正相关，与年龄和 LNM 呈负相关。与 LNM 频率降低相关的因素独立于其他预后因素。MMTV 样阳性与乳腺癌亚型的预后参数较好相关，这可能与其抗转移潜能和潜在的免疫环境激活有关。
