Takeo Minaguchi

Human papillomavirus infections among Japanese women: age-related prevalence and type-specific risk for cervical cancer

To obtain baseline data for human papillomavirus (HPV) screening and vaccination in Japan, we analyzed HPV DNA data from 2282 Japanese women (1517 normal cytology, 318 cervical intraepithelial neoplasia [CIN] grade 1, 307 CIN2–3, and 140 invasive cervical cancer [ICC]) that visited the University of Tsukuba Hospital or Ibaraki Seinan Medical Center Hospital for screening or treatment of cervical diseases between 1999 and 2007. An L1‐based PCR method was used for individual HPV genotyping. The most common HPV types in ICC were, in order of decreasing prevalence, HPV16 (40.5%), HPV18 (24.4%), HPV52 (8.4%), HPV58 (3.1%), and HPV33 (3.1%). Based on the comparison of HPV type distributions between normal cytology and CIN2–3 and ICC, estimated risk of disease progression varied considerably by genotype: HPV16, HPV18, HPV31, HPV33, HPV35, HPV52, and HPV58 (prevalence ratio, 1.92; 95% confidence interval 1.58–2.34); other oncogenic types (0.31, 95% confidence interval 0.19–0.50); and non‐oncogenic types (0.09, 95% confidence interval 0.03–0.43). HPV16 and/or HPV18, including coinfections with other types, contributed to 67.1% of ICC and 36.2% of CIN2–3 among Japanese women. More importantly, the overall prevalence of HPV16 and/or HPV18 varied greatly according to the womens age: highest in women aged 20–29 years (ICC, 90.0%; CIN2–3, 53.9%), decreasing with age thereafter, and lowest in women aged 60 years or older (ICC, 56.3%; CIN2–3, 25.0%). In conclusion, type‐specific HPV testing may help identify Japanese women at high risk of progression to CIN2–3 and cancer. In Japan, current HPV vaccines are estimated to provide approximately 70% protection against ICC and may be more useful in reducing the incidence of cervical cancer and precancer in young women of reproductive age. (Cancer Sci 2009; 100: 1312–1316)

A Single Nucleotide Polymorphism in the Matrix Metalloproteinase-1 Promoter in Endometrial Carcinomas

Recent studies demonstrated that a single guanine insertion polymorphism in a matrix metalloprotease‐1 promoter created an Ets binding site and affected the elevation of the transcriptional level of matrix metalloproteinase‐1 (MMP‐1). Furthermore, in tumor cell lines derived from melanoma and breast cancer, the incidence of the 2G/2G genotype was significantly higher than that in the normal population. To evaluate the contribution of this polymorphism in endometrial carcinomas, we genotyped 100 endometrial carcinomas and then analyzed immunoexpression of MMP‐1 in these carcinomas. We found that endometrial carcinoma patients showed a significantly higher rate of 1G/2G or 2G/2G genotype than control individuals, and that tumors containing the 2G allele(a) expressed MMP‐1 protein more frequently than those with 1G/1G genotype. Therefore, the single nucleotide polymorphism at the MMP‐1 promoter affected the expression level of the MMP‐1 protein, which may result in the association with more aggressive character in endometrial carcinoma. Our result suggests that the presence of 2G polymorphism at the MMP‐1 promoter may be one of the risk factors for the development and/or progression of endometrial carcinoma.

Isolation, mapping, and functional analysis of a novel human cDNA (BNIP3L) encoding a protein homologous to human NIP3

We have isolated a novel cDNA that encodes a product showing significant sequence homology (56% identity) to human NIP3, a protein thought to interact with adenovirus E1B19kD and human BCL2 proteins. This cDNA contains an open reading frame of 657 nucleotides encoding a 219 amino acid polypeptide. The gene, designated BNIP3L, was expressed in all 16 normal human tissues examined; we mapped it to chromosome band 8p21 by fluorescence in situ hybridization. Introduction of the BNIP3L gene into six different cancer‐cell lines caused significant growth suppression in each of them, while no such effect occurred when the antisense cDNA or the vector DNA was transfected, indicating that BNIP3L may function as a tumor suppressor. Genes Chromosomes Cancer 21:230–235, 1998.

Silent venous thromboembolism before treatment in endometrial cancer and the risk factors

Venous thromboembolism (VTE) often occurs after surgery and can even occur before surgery in patients with gynaecological malignancies. We investigated the incidence of VTE before treatment of endometrial cancer and associated risk factors. Plasma D-dimer (DD) levels before initial treatment were examined in 171 consecutive patients with endometrial cancer. Venous ultrasound imaging (VUI) of the lower extremities was performed in patients with DD ⩾1.5 μg ml−1, as the negative predictive value of DD for VTE is extremely high. For patients with deep vein thrombosis (DVT), pulmonary scintigraphy was performed to ascertain the presence of pulmonary thromboembolism (PTE). Risk factors for VTE were analysed using univariate and multivariate analyses for 171 patients. Of these, 37 patients (21.6%) showed DD ⩾1.5 μg ml−1, 17 (9.9%) displayed DVT by VUI and 8 (4.7%) showed PTE on pulmonary scintigraphy. All patients with VTE were asymptomatic. Univariate analysis for various risk factors revealed older age, non-endometrioid histology and several variables of advanced disease as significantly associated with VTE before treatment. Obesity, smoking and diabetes mellitus were not risk factors. Multivariate analysis confirmed extrauterine spread and non-endometrioid histology as independently and significantly associated with risk of VTE. These data suggest that silent or subclinical VTE occurs before treatment in at least around 10% of patients with endometrial cancer. Risk factors for VTE before treatment might not be identical to those after starting treatment.

Distinct lymphatic spread of endometrial carcinoma in comparison with cervical and ovarian carcinomas

The distribution of metastatic pelvic lymph nodes (PLNs) and aortic lymph nodes (ALNs) in 27 node-positive endometrial carcinomas (ECs) was analyzed in comparison with that in 25 node-positive cervical carcinomas (CCs) and 58 node-positive ovarian carcinomas (OCs). All patients underwent systematic pelvic and aortic lymphadenectomy. Lymph nodes were classified into the five subgroups: ALN above the inferior mesenteric artery (IMA; A1), ALN below the IMA (A2), the common iliac and sacral LNs (P1), the internal and external iliac LNs and obturator LNs (P2) and the suprainguinal LNs (P3). EC was similar to CC in that metastases to P2 were more frequent compared to A1 or A2, whereas EC and OC shared a common feature in that A1, A2 and P2 were involved at high rates. ALN metastases were significantly associated with P1 positivity in both EC and CC (P<0.05), but not in OC. However, the incidence of both ALN and PLN metastases in EC (67%) was similar to that in OC (61%), being much higher than that in CC (36%). ALN involvement alone was observed in 7% for EC, 0% for CC and 21% for OC. Based on the distribution of LN metastases, it appears that CC metastasizes primarily to PLN, whereas OC metastasizes almost equally to both PLN and ALN. Interestingly, EC can directly metastasize to both PLN and ALN with PLN metastases being dominant, a distinct lymphatic spread pattern better viewed as being somewhere between CC and OC.

PIK3CA overexpression is a possible prognostic factor for favorable survival in ovarian clear cell carcinoma

Dysregulated signaling on the PI3-kinase/Akt cascade is reportedly associated with early stage and favorable prognosis in some kinds of malignancies including breast cancer, endometrial cancer, and colorectal cancer. PIK3CA, a catalytic subunit of PI3-kinase, is known to be activated in ovarian clear cell carcinoma (CCC), which is categorized as type I ovarian cancer. The aim of this study was to investigate the clinical significance of PIK3CA overexpression in the disease. We performed immunohistochemical analyses of PIK3CA, PTEN, p-Akt, p27 and p53 expressions in primary ovarian clear cell carcinomas from 62 Japanese patients. Genetic analyses of PIK3CA mutation and amplification were further conducted. PIK3CA was overexpressed in 45 tumors (73%), PTEN expression was negative in 3 (5%), and p53 was positive in 8 (13%). Overexpressed PIK3CA was found to be associated with p-Akt overexpression (P = .007). PIK3CA overexpression tended to be observed in more of stage I disease (73% versus 47%, P = .07) and was associated with absence of residual tumor at the initial surgery (96% versus 71%, P = .01). Furthermore, survival analyses revealed that PIK3CA overexpression correlated with improved overall survival (P = .03). Subsequent genetic analyses demonstrated that PIK3CA overexpression correlated with the presence of mutation or amplification of the PIK3CA gene in tumors (P = .009). Our observations suggest that the subgroup of ovarian clear cell carcinomas harboring activated PIK3CA seems to have better prognosis possibly due to more indolent biological property compared to tumors without PIK3CA activation. PIK3CA may serve as a biomarker for good prognosis and a possible therapeutic target in this lethal subtype of ovarian cancer.

Human homolog of Drosophila tumor suppressor Scribble negatively regulates cell-cycle progression from G1 to S phase by localizing at the basolateral membrane in epithelial cells

Drosophila tumor suppressor Scribble has been identified as an apical‐basolateral polarity determinant in epithelia. A human homolog of Drosophila Scribble, human Scribble (hScrib), has been identified as a protein targeted by human papillomavirus E6 for the ubiquitin‐mediated degradation dependent on E6AP, a cellular ubiquitin‐protein ligase. Human Scribble is classified as a LAP protein, having leucine‐rich repeats (LRRs) and PDZ domains. We investigated whether hScrib, which is thought to have a role in polarity determination based on the data of its Drosophila homolog, is involved in cell‐cycle regulation and proliferation control of epithelia. Transfection of hScrib inhibits cell‐cycle progression from G1 to S phase, and it up‐ and down‐regulates expression of adenomatous polyposis coli and cyclins A and D1, respectively. Knockdown of hScrib expression by siRNA leads to cell‐cycle progression from G1 to S phase. We explored functional domain mapping to reveal which domains of hScrib are critical for its cellular proliferation control and localization at the basolateral membrane. We found that LRRs and PDZ domain 1 are indispensable for hScrib to inhibit cell growth by blocking cell‐cycle progression and to keep its proper localization. These data indicate that basolateral membrane localization of hScrib is closely related to its proliferation control. Our findings suggest the possibility that hScrib is involved in signal transduction to negatively regulate cell proliferation by localizing at the basolateral membrane of epithelial cells through LRRs and PDZ domains. (Cancer Sci 2006; 97: 1217–1225)

Interleukin-10 −1082 Gene Polymorphism and Susceptibility to Cervical Cancer Among Japanese Women

Polymorphisms in cytokine genes can influence immune responses to human papillomavirus infection, possibly modifying risks of cervical cancer. Using an amplification refractory mutation system-polymerase chain reaction method, we analyzed a single nucleotide polymorphism (A/G) at position -1082 in interleukin-10 promoter region in 440 Japanese women: 173 women with normal cytology, 163 women with cervical intraepithelial neoplasia and 104 women with invasive cervical cancer. The carrier frequency of interleukin-10 -1082 G alleles associated with higher interleukin-10 production increased with disease severity: 9.8% for normal cytology; 19.6% for cervical intraepithelial neoplasia; 29.8% for invasive cervical cancer (P for trend < 0.001). Among cytologically normal women, human papillomavirus infections were more common in those who were positive for an interleukin-10 -1082 G allele (P = 0.04). In conclusion, our data suggest that interleukin-10 -1082 gene polymorphism may serve as a marker of genetic susceptibility to cervical cancer among Japanese women.

Loss of Hugl-1 expression associates with lymph node metastasis in endometrial cancer

Mutation of neoplastic tumor suppressor genes, scribble, discs large, and lethal giant larvae (lgl), causes disruption of cell polarity and overproliferation of Drosophila epithelial cells and neuroblasts. Reduced expression of human homologue of lgl, Hugl-1, has been reported to be involved in development and progression of human colon cancer and malignant melanoma. To explore the association between Hugl-1 expression and clinical character in endometrial cancer, we examined the expression of Hugl-1 in primary endometrial cancer tissues. The expression of Hugl-1 mRNA in 86 primary endometrial cancer tissues was examined using semiquantitative reverse transcription polymerase chain reaction (RT-PCR). All samples were categorized into two groups: Hugl-1 positive and Hugl-1 negative. Clinical data of each group were analyzed by Fishers exact probability test and survival rates of each group were compared by Kaplan-Meier method and Log-rank test. Loss of Hugl-1 expression had correlation with the higher incidence of lymph node metastasis, but not to the patients age at onset, distant metastasis, clinical stage, lymph or venous vessel invasion, or histopathological grade of differentiation. The Hugl-1-positive group had poorer prognosis compared with the Hugl-1-negative group. These results indicate that loss of Hugl-1 expression in endometrial cancer may contribute to lymph node metastasis and it can be a factor of poor prognosis.

Japan Society of Gynecologic Oncology guidelines 2015 for the treatment of vulvar cancer and vaginal cancer

BackgroundVulvar cancer and vaginal cancer are relatively rare tumors, and there had been no established treatment principles or guidelines to treat these rare tumors in Japan. The first version of the Japan Society of Gynecologic Oncology (JSGO) guidelines for the treatment of vulvar cancer and vaginal cancer was published in 2015 in Japanese.ObjectiveThe JSGO committee decided to publish the English version of the JSGO guidelines worldwide, and hope it will be a useful guide to physicians in a similar situation as in Japan.MethodsThe guideline was created according to the basic principles in creating the guidelines of JSGO.ResultsThe guidelines consist of five chapters and five algorithms. Prior to the first chapter, basic items are described including staging classification and history, classification of histology, and definition of the methods of surgery, radiation, and chemotherapy to give the reader a better understanding of the contents of the guidelines for these rare tumors. The first chapter gives an overview of the guidelines, including the basic policy of the guidelines. The second chapter discusses vulvar cancer, the third chapter discusses vaginal cancer, and the fourth chapter discusses vulvar Paget’s disease and malignant melanoma. Each chapter includes clinical questions, recommendations, backgrounds, objectives, explanations, and references. The fifth chapter provides supplemental data for the drugs that are mentioned in the explanation of clinical questions.ConclusionOverall, the objective of these guidelines is to clearly delineate the standard of care for vulvar and vaginal cancer with the goal of ensuring a high standard of care for all women diagnosed with these rare diseases.