Assessment for the timing of comprehensive genomic profiling tests in patients with advanced solid cancers

Comprehensive genomic profiling (CGP) tests have been covered by public insurance in Japan for patients with advanced solid tumors who have completed or are completing standard treatments or do not have them. Therefore, genotype-matched drug candidates are often unapproved or off-label, and improving clinical trial access is critical, involving the appropriate timing of CGP tests. To address this issue, we analyzed the previous treatment data for 441 patients from an observational study on CGP tests discussed by the expert panel at Hokkaido University Hospital between August 2019 and May 2021. The median number of previous treatment lines was two; three or more lines accounted for 49%. Information on genotype-matched therapies was provided to 277 (63%). Genotype-matched clinical trials were ineligible because of an excess number of previous treatment lines or use of specific agents were found in 66 (15%) patients, with the highest proportion in breast and prostate cancers. Many patients met the exclusion criteria of one to two or more treatment lines across cancer types. In addition, previous use of specific agents was a frequent exclusion criterion for breast, prostate, colorectal, and ovarian cancers. The patients with tumor types with a low median number (two or fewer) of previous treatment lines, including most rare cancers, primary unknown cancers, and pancreatic cancers, had significantly fewer ineligible clinical trials. The earlier timing of CGP tests may improve access to genotype-matched clinical trials, with their proportion varying by cancer type. Each relevant society needs to advocate the desirable timing of CGP testing nationwide.

Distribution of human papilloma virus genotypes and treatment outcomes in definitive radiotherapy for cervical cancer

Most oncogenic human papilloma virus (HPV) genotypes stratify into two species, α-7 HPV and α-9 HPV. There are several studies that evaluate the relationship between HPV species and treatment outcomes and reports that HPV species is prognostic. The HPV genotyping was conducted using biopsy specimens which had been stored in these studies. We conducted the study using the HPV test performed by cytology specimens which is less invasive and more useful in clinical settings. This study enrolled 46 patients who received HPV genotyping before the definitive radiotherapy. The results of the HPV genotyping were classified into HPVα-7, HPVα-9 and negatives. Of the 46 patients, 10 were positive for HPVα-7, 21 positive for HPVα-9 and 15 were negative. The median follow-up period was 38 months (range 4-142). The HPVα-7, HPVα-9 and negative groups showed the 3-year overall survival (OS; 59.3%, 80.4% and 72.2% [P = 0.25]); local control (LC; 67.5%, 81% and 80% [P = 0.78]); pelvic control (PC) (50%, 81% and 72.7% [P = 0.032]); pelvic lymph node (PLN) control (78.7%, 95% and 92.3% [P = 0.012]); distant metastasis free (DMF) survival (50%, 75.4% and 42.8% [P = 0.098]); and progression free survival (PFS) rate of patients (30%, 66.7% and 38.9% [P = 0.085]), respectively. Patients with HPVα-7 showed statistically significant poorer PC than the HPVα-9 group, in multivariate analysis. This result is consistent with previous studies for HPV positive patients. The HPV negativity rate was higher in this study than in other studies and further work on this may be needed for clinical use.

Combination therapy with bevacizumab and a CCR2 inhibitor for human ovarian cancer: An in vivo validation study

BACKGROUND

Anti-angiogenic therapy with bevacizumab (BEV), an anti-VEGF antibody, plays a critical role in the treatment of ovarian cancer. However, despite an encouraging initial response, most tumors become resistant to BEV over time, and a new strategy that enables sustainable treatment using BEV is therefore needed.

METHODS

To overcome the resistance to BEV in patients with ovarian cancer, we performed a validation study of combination therapy with BEV (10 mg/kg) and the CCR2 inhibitor BMS CCR2 22 (20 mg/kg) (BEV/CCR2i) using 3 consecutive patient-derived xenografts (PDXs) of immunodeficient mice.

RESULTS

BEV/CCR2i demonstrated a significant effect of growth suppression in the BEV-resistant serous PDX and BEV-sensitive serous PDX compared with BEV (30.4% after the second cycle and 15.5% after the first cycle, respectively), and treatment cessation did not attenuate this effect. Tissue clearing and immunohistochemistry with an anti-α-SMA antibody suggested that BEV/CCR2i suppressed angiogenesis from the host mice more than BEV. In addition, human CD31 immunohistochemistry revealed that BEV/CCR2i decreased microvessels originating from the patients to a significantly greater degree than BEV. Regarding the BEV-resistant clear cell PDX, the effect of BEV/CCR2i was unclear during the first five cycles, but the following two cycles of increased-dose BEV/CCR2i (CCR2i 40 mg/kg) significantly suppressed tumor growth compared with BEV (28.3%) by inhibiting the CCR2B-MAPK pathway.

CONCLUSIONS

BEV/CCR2i showed a sustained anticancer immunity-independent effect in human ovarian cancer that was more significant in serous carcinoma than in clear cell carcinoma.

Germline PRDM1 Variant rs2185379 in Long-Term Recurrence-Free Survivors of Advanced Ovarian Cancer

PURPOSE

To identify the germline genetic characteristics of long-term recurrence-free survivors that can be applied to establishing a new strategy for curing advanced cancer, we investigated the whole-genome single nucleotide variants of ovarian cancer patients.

PATIENTS AND METHODS

DNA specimens were obtained from rare long-term recurrence-free survivors with FIGO stage III-IV ovarian cancer with no recurrence for 8-23 years after primary treatments for a whole-genome analysis of approximately 660,000 single nucleotide variants. We then established a mouse model with a notable gene alteration by CRISPR/Cas9 to confirm the biological role.

RESULTS

The long-term recurrence-free survivors more frequently had germline heterozygous variant rs2185379 of the PRDM1 gene exon than patients with early recurrence (6.8-fold, P=0.013) and the general population. In the mouse model, primary intraperitoneal disseminated tumors of allograft ID8 were significantly smaller in the germline heterozygous rs2185379 group than in the wild-type group (57.4% decrease, P=0.008). Immunohistochemistry showed that the area of distribution of infiltrating T lymphocytes with positive CD8 staining was significantly increased in the germline heterozygous rs2185379 group in comparison to the wild-type group.

CONCLUSION

Germline heterozygous rs2185379 in PRDM1 is correlated with an excellent prognosis and can be used to establish a new strategy for treating advanced ovarian cancer.

Patterns and predictors of site-specific recurrence in cervical cancer after radical hysterectomy

AIM

This study examines patterns and predictors of site-specific recurrence to explore the causes of local recurrence of cervical cancer.

METHODS

Radical hysterectomy was performed in 121 patients (stage IB-IIB). Nerve-sparing was performed whenever possible. The first recurrence in local, regional, and distant areas was examined. We investigated the possibility of nerve involvement in local recurrence, focusing on paravaginal tissues containing the pelvic plexus. We provide Supporting Information on local recurrence in the paravaginal area.

RESULTS

Local recurrence was an independent event from regional or distant recurrence. Local recurrence was seen only in high-risk patients, while regional and distant recurrences were not or less related to the risk category. The independent risk factors by logistic regression for local, regional, and distant recurrence were parametrial invasion, vaginal invasion, and lymph node metastasis, respectively. Local recurrence showed a comparable or more significant negative impact on survival than distant recurrence. Among seven patients with local recurrences, five had a recurrence in the paravagina. The rate of paravaginal recurrence was one in 76 early-stage and four in 45 locally advanced diseases. Four sites of paravaginal recurrence occurred on the nerve-sparing side and two on the non-nerve-sparing side. Supporting Information demonstrated histological evidence of perineural spread into the pelvic plexus and perineural invasion of the primary tumor.

CONCLUSIONS

A high percentage of local recurrences are in paravaginal tissue containing the pelvic plexus. The causal association of nerve-sparing surgery and perineural invasion with local recurrence needs to be investigated in large prospective studies.

The difficulty to diagnose cervical cancer developing in the perinatal period with the first-trimester cytology: A retrospective study

AIM

Cytological cervical cancer screening for pregnant women is routinely performed and still plays an essential role in Japan because of the considerably low rate of human pappillomavirus (HPV) vaccination. Though almost all pregnant women undergo cytological screening at their first trimester, we experienced invasive cervical cancers (ICC) diagnosed during pregnancy or postpartum period. We investigated the characteristics of perinatally diagnosed ICCs to clarify the difficulty in diagnosis during the pregnancy.

METHODS

We retrospectively reviewed the clinical data on ICC diagnosed during pregnancy or within 1 year after delivery from 2010 to 2018 at Hokkaido University Hospital.

RESULTS

We identified 18 ICC patients, and the median follow-up period was 46.5 months. Among eight patients with negative for intraepithelial lesion or malignancy (NILM), the mean duration to reach ICC diagnosis was 10.7 months, seven had stage IB1 or worse, and one was dead. On the other hand, among 10 women with abnormal cytology, the mean duration for diagnosis was 1.4 months, and 6 had stage IB1 or worse, and 1was dead. In terms of the timing of the final diagnosis, 8 were during pregnancy and 10 in the postpartum periods. Among eight pregnant patients, three resulted in a preterm delivery (33, 34, and 35 gestational weeks), and four terminated their pregnancies. One decided to continue the pregnancy until the term period. We performed conization in one patient and hysterectomy in seven.

CONCLUSION

A part of cytological examinations of pregnant women may result in presumed false-negative or underestimation, which keeps them away from the additional examination to find ICC.

Adding aprepitant to palonosetron does not decrease carboplatin-induced nausea and vomiting in patients with gynecologic cancer

BACKGROUND

Recently, aprepitant has been recommended in carboplatin-based regimens, but there are limited reports on the efficacy of administering aprepitant, palonosetron, and dexamethasone (DEX) in carboplatin-containing regimens. Moreover, because aprepitant is an expensive drug, confirming its effectiveness is very important from the medical cost perspective. In this study, we examined the efficacy of prophylactically administered aprepitant, palonosetron and DEX, in paclitaxel and carboplatin (TC) combination chemotherapy.

METHODS

Patients with gynecologic cancer who were treated with paclitaxel (175 mg/m2) and carboplatin (area under the curve, AUC = 5-6) combination chemotherapy were retrospectively evaluated. The complete response (CR) rate, severity of nausea, and incidence of anorexia in the first course were compared between patients who did not receive aprepitant (control group) and those who received (aprepitant group).

RESULTS

The 106 patients were divided into two groups, consisting of 52 and 54 the control and aprepitant groups, respectively, and the patient background showed no significant difference between both groups. The CR rate of the overall phase between the control and aprepitant groups was 73.1 vs. 74.1%, that in the acute phase was 98.1 vs. 100%, and in the delayed phase was 75.0 vs. 74.1%, respectively, without any significant difference. The severity of nausea and incidence of anorexia were also not significantly different between both groups.

CONCLUSIONS

The results of the study suggest that adding aprepitant to palonosetron and DEX does not prevent carboplatin-induced nausea and vomiting in gynecologic cancer patients. Therefore, adding aprepitant to palonosetron does not decrease carboplatin-induced nausea and vomiting in patients with gynecologic cancer.

Clinical significance of comprehensive genomic profiling tests covered by public insurance in patients with advanced solid cancers in Hokkaido, Japan

BACKGROUND

Comprehensive cancer genomic profiling has been used recently for patients with advanced solid cancers. Two cancer genomic profiling tests for patients with no standard treatment are covered by Japanese public health insurance since June 2019.

METHODS

We prospectively analyzed data of 189 patients with solid cancers who underwent either of the two-cancer genomic profiling tests at Hokkaido University Hospital and its liaison hospitals and whose results were discussed in molecular tumor board at Hokkaido University Hospital between August 2019 and July 2020.

RESULTS

All 189 patients had appropriate results. Actionable gene alterations were identified in 93 patients (49%). Frequent mutations included PIK3CA (12%) mutation, BRCA1/2 alteration (7%), ERBB2 amplification (6%) and tumor mutation burden-High (4%). The median turnaround time from sample shipping to acquisition by the expert panel was 26 days. Although 115 patients (61%) were provided with information for genotype-matched therapies, only 21 (11%) received them. Notably, four of eight patients below the age of 20 years were provided information for genotype-matched therapies, and three received them. Their response rates and disease control rates were 29% and 67%, respectively. Most patients who did not undergo the genotype-matched therapies were provided information for only investigational drugs in phases I and II at distant clinical trial sites in central Japan. Twenty-six patients were informed of suspected germline findings, while 11 patients (42%) received genetic counseling.

CONCLUSIONS

The publicly reimbursed cancer genomic profilings may lead to the modest but favorable therapeutic efficacy of genotype-matched therapy for solid cancer patients with no standard therapy. However, poor access to genotype-matched therapy needs to be resolved.

The disease sites of female genital cancers of BRCA1/2-associated hereditary breast and ovarian cancer: a retrospective study

Disease sites of female genital tract cancers of BRCA1/2-associated hereditary breast and ovarian cancer (HBOC) are less understood than non-hereditary cancers. We aimed to elucidate the disease site distribution of genital cancers in women with the germline BRCA1 and BRCA2 pathogenic variants (BRCA1+ and BRCA2+) of HBOC. For the primary disease site, the proportion of fallopian tube and peritoneal cancer was significantly higher in BRCA2+ (40.5%) compared with BRCA1+ (15.4%) and BRCA− (no pathogenic variant, 12.8%). For the metastatic site, the proportion of peritoneal dissemination was significantly higher in BRCA1+ (71.9%) than BRCA− (55.1%) and not different from BRCA2+ (71.4%). With one of the most extensive patients, this study supported the previous reports showing that the pathogenic variants of BRCA1/2 were involved in the female genitalia’s disease sites.

Risk factors for lymph node metastasis of ovarian, fallopian tube and primary peritoneal cancer in hereditary breast and ovarian cancer syndrome

BACKGROUND

To establish an individualized surgical strategy for lymphadenectomy in ovarian cancer patients with the germline BRCA1 and BRCA2 pathogenic variants (BRCA1+ and BRCA2+), we investigated the clinicopathological characteristics that are involved in the increased risk of lymph node metastasis.

METHODS

We retrospectively reviewed the data of Japanese women registered in the database of the Japanese Hereditary Breast and Ovarian Cancer Consortium, who underwent BRCA1 and BRCA2 genetic testing.

RESULTS

We evaluated the predictors of lymph node metastasis in all patients with the information of age at the diagnosis, disease site, histological subtype, 2014 FIGO stage, personal breast cancer history and family history; 233, 153 and 32 patients in the BRCA- (no pathogenic variant), BRCA1+ and BRCA2+ groups, respectively. The prevalence of lymph node metastasis was not markedly different between BRCA- (20.0%), BRCA1+ (18.4%) and BRCA2+ (26.2%). Multivariate analysis revealed an absence of a family history of ovarian cancer as an independent predictor for an increased risk of lymph node metastasis in BRCA1+, and the prevalence of lymph node metastasis was 11.7 and 42.0% in the groups with and without a family history of ovarian cancer, respectively. This subgroup without a family history of ovarian cancer did not show any correlation with a particular variant of BRCA1, including two common variants of c.188 T > A and c.2800C > T.

CONCLUSIONS

This study suggested that certain genetic factors related to the penetrance of hereditary breast and ovarian cancer syndrome altered the frequency of lymph node metastasis in BRCA1+ ovarian cancer, and family history may be useful to personalize the indication of lymphadenectomy.

Four versus six chemotherapy cycles in endometrial carcinoma with a high risk of recurrence: a retrospective study

OBJECTIVE

This study compared the survival outcomes and the incidence of chemotherapy-related adverse events in endometrial cancer patients who received four and six cycles of adjuvant chemotherapy to examine the optimal number of adjuvant chemotherapy cycles.

METHODS

A total of 112 patients with endometrial cancer with a high risk of recurrence were retrospectively enrolled; 46 patients received four cycles and 66 received six cycles of adjuvant chemotherapy. Between-group differences of overall survival, disease-free survival, hematological and non-hematological toxicities were analyzed. Baseline patient's background differences were assessed with inverse probability of treatment weighting using propensity score.

RESULTS

Overall and disease-free survivals between the two groups were not significantly different. Paclitaxel + carboplatin, every 3-4 weeks was the most frequently used chemotherapy regimen in both groups. Patients in the six-cycle chemotherapy group developed neutropenia G4 or febrile neutropenia more frequently than those in the four-cycle group; odds ratio (95% confidence interval) is 4.07 (1.51-10.96). Peripheral sensory neuropathy was the most frequently observed non-hematological toxicity; the incidence of peripheral sensory neuropathy was not significantly different between four- and six-cycle chemotherapy group, P = 0.832. The result was same in the subgroup analysis in patients who received TC regimen, P = 0.455.

CONCLUSION

This study implies a possible benefit of fewer cycles of adjuvant chemotherapy in endometrial cancer patients with a high risk of recurrence because of the lower incidence of hematological toxicities without impairing survival outcomes.

Tailored radical hysterectomy for locally advanced cervical cancer

OBJECTIVE

The survival and prognostic factors for locally advanced cervical cancer treated with nerve-sparing Okabayashi-Kobayashi radical hysterectomy have not been elucidated. We aimed to evaluate the oncological outcomes of those patients after radical hysterectomy with adjuvant chemotherapy.

METHODS

This retrospective cohort study was conducted from January 2002 to December 2011. Treatment was conducted at a single tertiary center in northern Japan. We used the Okabayashi-Kobayashi radical hysterectomy with lymphadenectomy. We applied unilateral nerve preservation for stage IIA/IIB cancer if there was a one-sided extension of the disease outside the cervix. Indication for adjuvant therapy was based on Sedlis criteria. High-risk was defined as evidence of lymph node metastasis, pathological parametrial invasion, and a positive/close surgical margin. The choice of adjuvant therapy was chemotherapy which consisted of paclitaxel and cisplatin.

RESULTS

The study included 76 early-stage IB1 (≤4 cm) and IIA1 cervical cancer and 45 locally advanced stage IB2 (>4 cm), IIA2, and IIB disease treated consecutively. The median follow-up was 106 (range: 6-203) months. There were 18 (15%) patients with recurrence, with five of 76 in the early-stage (7%) and 13 of 45 in the locally advanced disease (29%) (P<0.001). For locally advanced cervical cancer, pT classification (P<0.001), lymph node metastasis (P=0.007), and histology (P=0.05) were associated with locoregional recurrence. The five-year locoregional recurrence rate in the locally advanced disease was 20% and 5% in the early-stage disease (P=0.01). The five-year disease-free survival in the locally advanced cervical cancer was 71% and 93% in the early-stage disease (P<0.001). The overall survival in locally advanced disease depended on the adeno-type histology and lymph node metastasis.

CONCLUSION

The tailored use of nerve-sparing Okabayashi-Kobayashi radical hysterectomy with adjuvant chemotherapy based on tumor histology and lymph node metastasis may be a possible option as a treatment of locally advanced cervical cancer in selected patients.

Low expression of gamma-glutamyl transpeptidase 1 is an independent poor prognostic factor in ovarian clear cell carcinoma, in relation to up-regulation of immune suppressive genes and EMT-related genes

6042

Background: Ovarian clear cell carcinoma (OCCC) is a distinct entity from other epithelial ovarian cancers such as the most prevalent high-grade serous cancer (HGSC), and often exhibit less sensitivity to platinum-based chemotherapy. Several studies using cell lines have reported that glutathione (GSH) metabolism plays an important role in chemo-resistance of OCCC. Here, we aimed to correlate the prognosis of OCCC and the expression of gamma-glutamyltransferase 1 (GGT1), one of the key enzymes in GSH metabolism. Methods: We prepared a FFPE-tissue microarray, and analyzed 56 OCCC patients with the follow-up periods over 3 years. Expression level of GGT1 was evaluated by immunohistochemistry (IHC) using H-score (0-300), and was correlated with clinical outcomes. The prognostic significance was assessed by multivariate analysis using Cox regression model. To investigate the possible related pathways, we performed transcriptome analysis using Ion AmpliSeq Transcriptome Human Gene Expression Kit (Thermo Fisher Scientific) from the frozen tissue specimens collected from 33 ovarian cancer patients including 15 OCCC patients and 18 HGSC patients. Results: The OCCC patients were divided into two populations in the histogram of H-score in IHC staining, and the cut-off value was 90; 44 cases showed GGT1-high, and remaining 12 cases were GGT1-low. Follow-up periods, FIGO stage, and optimal surgery rate were not significantly different between two groups. However, platinum-resistant recurrent rate was significantly higher (42% vs. 14%, p=0.027), and overall survival (OS) was significantly shorter (5-year OS; 42% vs. 72%, p=0.0226) in GGT1-low OCCC. Multivariate analysis revealed that low expression of GGT1 was one of the independent poor prognostic factors as well as platinum-drug resistance. In enrichment analysis, the genes related to GSH metabolism, such as SLC3A1, GGT1, CSE, and GPX3 were up-regulated and positively correlated with HNF1B expression in OCCC. The expression level of GGT1 was inversely correlated with that of immune suppressive genes (TGF-b, IFNG, IL10, FOXP3, PD-L1, CTLA4) and epithelial-mesenchymal transition (EMT)-related genes (CDH2, VIM, TWIST1, ZEB1, ZEB2) in OCCC samples. Conclusions: Low expression of GGT1 is an independent poor prognostic factor probably in part due to suppression of tumor immunity and induction of EMT in OCCC.

Oncological Outcomes After Okabayashi-Kobayashi Radical Hysterectomy for Early and Locally Advanced Cervical Cancer

Importance

The role of surgery in early-stage cervical cancer has been established, but it is controversial in locally advanced cervical cancer.

Objective

To determine whether a radical hysterectomy method with extended removal of paracervical tissue for locally advanced cervical cancer is associated with satisfactory oncological outcomes.

Design, Setting, and Participants

This retrospective cohort study was conducted from January 1, 2002, to December 31, 2011, and participants were patients with cervical cancer at a single tertiary center in Northern Japan. The median follow-up period was 106 months, and none of the patients were lost to follow-up at less than 60 months. Data analyses were performed from July 1, 2017, to December 31, 2018.

Exposures

Patients underwent radical hysterectomy using the Okabayashi-Kobayashi method. Bilateral nerve preservation was used for stage IB1/IB2 disease and unilateral nerve preservation for stage IIA/IIB if disease extension outside the uterine cervix was 1-sided. Chemotherapy was used as the choice of adjuvant treatment for patients with an intermediate or high risk of recurrence, while some patients chose or were assigned to radiotherapy.

Main Outcomes and Measures

Primary outcomes were the 5-year local control rate and 5-year overall survival rate along with risk factor analysis.

Results

Of 121 consecutive patients, 76 (62.8%) had early-stage cervical cancer in 2008 International Federation of Gynecology and Obstetrics stages IB1 and IIA1 and 45 (37.2%) had locally advanced cervical cancer in stages IB2, IIA2, and IIB. The median (range) age was 42 (26-68) years. Adjuvant radiotherapy was used in 2 patients (3%) with early-stage cervical cancer and 3 (7%) of those with locally advanced cervical cancer. The 5-year local control rates for early-stage cervical cancer and locally advanced cervical cancer were 99% and 87%, respectively. The 5-year overall survival rates for early-stage cervical cancer and locally advanced cervical cancer were 95% and 82%, respectively. Cox regression analysis showed that lymph node metastasis and histology of adeno(squamous)carcinoma were independent risk factors for the overall survival of patients with cervical cancer treated with radical hysterectomy.

Conclusions and Relevance

The nerve-sparing Okabayashi-Kobayashi radical hysterectomy for locally advanced cervical cancer may provide survival not inferior to radical hysterectomy or radiotherapy in published literature. The applicability of radical hysterectomy with adjuvant chemotherapy for locally advanced cervical cancer needs to be validated by prospective comparative trials.

L1CAM Predicts Adverse Outcomes in Patients with Endometrial Cancer Undergoing Full Lymphadenectomy and Adjuvant Chemotherapy

BACKGROUND

L1 cell adhesion molecule (L1CAM) has been established as an important predictor of poor survival of early-stage endometrial cancer patients. We investigated whether L1CAM remains a significant predictor of poor survival of patients with advanced-stage endometrial cancer undergoing extensive surgical staging and adjuvant chemotherapy.

METHODS

We prepared tissue microarray (TMA) from surgical tissue specimens of 161 endometrial cancer patients who underwent full lymphadenectomy combined with adjuvant chemotherapy for patients at risk for recurrence, and evaluated expression of L1CAM using immunohistochemistry. The correlation between L1CAM positivity and clinicopathological factors and the prognostic significance of L1CAM expression was investigated.

RESULTS

Among 161 cases who had a follow-up duration of over 3 years, 48 cases (29.8%) showed positive staining for L1CAM. L1CAM positivity was significantly correlated with non-endometrioid histology (p < 0.0001), vascular invasion (p = 0.0157), and positive cytology (p = 0.005), and was a significant predictor of poor survival among advanced-stage patients, but not early-stage patients in our cohort. L1CAM-positive patients showed a higher recurrence rate and frequency of distant failure than L1CAM-negative patients. Multivariate analysis revealed that para-aortic lymph node metastasis (PANM) and L1CAM positivity were independent predictors of poor survival. Overall survival can be stratified into three groups by the combination of PANM and L1CAM positivity.

CONCLUSION

L1CAM is an independent predictor of poor survival in endometrial cancer patients undergoing full lymphadenectomy and adjuvant chemotherapy, thus indicating that L1CAM can be clinically used as a biomarker to identify those patients at increased risk of recurrence.

High-risk Human Papillomavirus Testing in Young Japanese Women with Atypical Squamous Cells of Undetermined Significance

Introduction:

The mortality due to uterine cervical cancer has been gradually increasing in women under 40 years of age (U40) in Japan. We investigated the effect of high-risk human papillomavirus (HR-HPV) on U40 subjects without any overt cytological abnormalities.

Materials and Methods:

We retrospectively examined the clinical data, including the findings of a cobas 4800 HPV test that was approved in Japan in 2013 to triage women with atypical squamous cells of undetermined significance (ASC-US) and a histological examination in 589 Japanese women.

Results:

The overall prevalence rate of HR-HPV was 34.5%. Biopsy-confirmed cervical intraepithelial neoplasia (CIN) 2, or worse (CIN2+) was identified in 45.1% (23/51) of HR-HPV-positive women with ASC-US, who underwent colposcopy immediately. The mean period from the HPV test to the diagnosis of CIN2+ was 3.7 months. CIN2+ was more common (69.6%) in U40 patients. The rates of single or multiple infections of HPV-16, HPV-18, and 12 other HR-HPV (31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68) in CIN2+ U40 patients were 31.3%, 0%, and 81.3%, respectively. The relative risk for CIN 2+ among U40 women with HPV-16 was not significantly different from that of the patients with infection of any of the 12 other HR-HPVs.

Conclusion:

The results of this study suggest that the 12 other HR-HPVs have a potential to generate high-grade cervical lesions among young women, and the examination rate of colposcopy should be increased.

Abstract 4020: Correlation between the expression of glutathione metabolism-related genes and prognosis in ovarian clear cell carcinoma

Background: Ovarian clear cell carcinoma (OCCC) is more prevalent in Japan than western countries, exhibits chemoresistant phenotype and poor survival. Although the expression of the genes related to glutathione (GSH) metabolism had been reported as one of the possible chemoresistant mechanisms, correlation between the expressions of these genes and prognosis in OCCC patients remains unclear. In this study, we aim to investigate 1) enrichment pathway analysis in OCCC in comparison with high-grade serous carcinoma (HGSC), and 2) correlation between the expression of gamma-glutamyl transpeptidase 1 (GGT1), one of the enzymes in GSH metabolism and prognosis.

Methods: We consecutively collected surgically resected tissue specimens from 33 ovarian cancer patients; 15 patients with OCCC and 18 patients with HGSC. The tissue specimens were collected in the vials containing RNA later® within 10 min. after resection of tumors. Total RNAs were extracted from the tumor tissues, and comprehensive gene expression analysis was performed using Ion AmpliSeq™ Transcriptome Human Gene Expression Kit (Thermo Fisher Scientific). For prognostic analysis, we used a tissue microarray (TMA) from 56 consecutive patients pathologically diagnosed with OCCC in our hospital, and assessed by immunohistochemistry (IHC) using H-score ranging from 0 to 300. Overall survival (OS) was estimated by Kaplan-Meier method, and analyzed by Cox-regression hazard model in multivariate analysis.

Results: Gene expression profiles revealed that TCF1/2 target genes were up-regulated in OCCC samples in comparison with HGSC. In addition, genes related with amino-acid transporters, such as SLC3A1, a cystine transporter, and genes related to GSH metabolism, including GGT1, CSE, and GPX3 were also up-regulated. In the OCCC patients with high expression level of GSH-related genes, FOXP3 was down-regulated but the T-cell inflamed genes were not varied compared to the OCCC patients with low expression level. The expression level of GGT1 in gene expression analysis was strongly correlated with H-score of GGT1 in IHC (r = 0.7850, p = 0.0023). In prognostic analysis, there were no significant differences during follow up period (57.5 months vs. 53 months), FIGO stage (I: 50% vs 64%), optimal surgery (92% vs. 98%), or recurrent rate (42% vs. 30%) between GGT1 positive (n = 44) and negative (n = 12) OCCC in IHC. However, platinum-drug resistant recurrent rate was significantly higher in GGT1 negative OCCC than GGT1 positive OCCC (42% vs 14%, p = 0.027). OS in GGT1 negative OCCC was significantly worse than that of GGT1 positive OCCC (5-year OS was 42% vs 72%, p = 0.0226), and negative expression of GGT1 was one of the independent poor prognostic factors in OCCC.

Conclusion: Negative expression of GGT1 in OCCC might be a poor prognostic maker via recruitment of regulatory T cells in tumor microenvironments.

Citation Format: Hiroshi Asano, Ryosuke Matsuoka, Kanako C. Hatanaka, Yutaka Hatanaka, Tatsuya Kato, Yosuke Konno, Takashi Mitamura, Hirotoshi Akita, Yoshihiro Matsuno, Hidemichi Watari. Correlation between the expression of glutathione metabolism-related genes and prognosis in ovarian clear cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4020.

Molecular-targeted therapies and precision medicine for endometrial cancer

The overall survival rate of patients with early-stage endometrial cancer is relatively high; however, there are few treatment options for patients with advanced or recurrent endometrial cancer, and the prognosis of such patients remains poor. Recent progress in molecular-targeted therapies demonstrated that they have the potential to improve the long-term survival of cancer patients with appropriate biomarkers. However, the median progression-free survival of patients who received single-agent molecular-targeted therapy was <5 months, and the development of molecular-targeted therapies for endometrial cancer patients is urgently needed. This review highlights the previous efforts, including antiangiogenesis therapy, PI3K/AKT/mTOR pathway inhibitor treatment and epidermal growth factor receptor inhibitor treatment and reports on ongoing phase 2 clinical trials, including immune checkpoint inhibitor and PARP inhibitor. We also summarized the genetic background of endometrial cancer according to The Cancer Genome Atlas data and considered the theoretical background for future efforts to prolong the survival of patients with refractory endometrial cancer and for other interesting challenges.

Case Study of Clinical Behavior Analysis for a 20-Year-Old Client With Emetophobia

This case study illustrates a clinical behavior analytic intervention for a female client with emetophobia, the fear of vomiting. Clinical behavior analysis is a recently developing branch of empirically supported psychotherapy, derived from behavior analysis. This case study presents modified case formulations and changed intervention strategies according to the results of repeated measuring. The intervention was six sessions and three gradual follow-up sessions; the effect of the intervention was monitored by a single-case design. The intervention strategies were changed from symptom-focused interventions, which are based on exposure, to value-focused gradual follow-up sessions. The client’s phobia and depression were alleviated through the intervention and gradual follow-up phases. Moreover, her value-based activities increased through the gradual follow-up phase. The Reliable Change Indexes (RCIs) were calculated to evaluate changes between the intervention and follow-up phases. There were large and clinically significant decreases on measures. The results highlight the utility of repeated measuring and importance of a value-focused approach.

PRKRA/PACT Expression Promotes Chemoresistance of Mucinous Ovarian Cancer

For mucinous ovarian cancer (MOC), standard platinum-based therapy is largely ineffective. We sought to identify possible mechanisms of oxaliplatin resistance of MOC and develop strategies to overcome this resistance. A kinome-based siRNA library screen was carried out using human MOC cells to identify novel targets to enhance the efficacy of chemotherapy. In vitro and in vivo validations of antitumor effects were performed using mouse MOC models. Specifically, the role of PRKRA/PACT in oxaliplatin resistance was interrogated. We focused on PRKRA, a known activator of PKR kinase, and its encoded protein PACT because it was one of the five most significantly downregulated genes in the siRNA screen. In orthotopic mouse models of MOC, we observed a significant antitumor effect of PRKRA siRNA plus oxaliplatin. In addition, expression of miR-515-3p was regulated by PACT-Dicer interaction, and miR-515-3p increased the sensitivity of MOC to oxaliplatin. Mechanistically, miR-515-3p regulated chemosensitivity, in part, by targeting AXL. The PRKRA/PACT axis represents an important therapeutic target in MOC to enhance sensitivity to oxaliplatin.

miR-363 confers taxane resistance in ovarian cancer by targeting the Hippo pathway member, LATS2

Ovarian cancer is the most aggressive female reproductive tract tumours. Taxane (paclitaxel; TX) is widely used for ovarian cancer treatment. However, ovarian cancers often acquire chemoresistance. MicroRNAs (miR) have been reported to mediate many tumours'chemoresistance. We investigated the role of miR-363 in the chemoresistance of the ovarian cancer cell line, KF, and its TX-resistant derivative (KF-TX) cells. QRT-PCR indicated that miR-363 was upregulated in KF-TX cells, and introduction of miR-363 into sensitive ovarian cancer cells confers TX-resistance and significantly inhibited the expression of the Hippo member, LATS2, as indicated by viability, clonogenic assay and expression analysis. Furthermore, we validated the role of LATS2 in TX-response by sh-based silencing, which also confers TX-resistance to the ovarian cancer cells. On the other hand, specific inhibitor against miR-363 restored the response to TX in the resistant cells. In addition, miR-363 was found to bind to the 3'-UTR of LATS2 mRNA, confirming that miR-363 directly targets LATS2 as indicated by dual luciferase assay. RT-PCR-based evaluation of miR-363 in a panel of human ovarian tumours revealed its upregulation in most of the tumour tissues identified as resistant while it was downregulated in most of the tissues identified as sensitive ones. Moreover, higher levels of miR-363 in human ovarian cancer specimens were significantly correlated with TX chemoresistance. Taken together, our study reveals the involvement of miR-363 in chemoresistance by targeting LATS2 in ovarian cancers, raising the possibility that combination therapy with a miR-363 inhibitor and TX may increase TX efficacy and reduce the chance of TX-resistance.

Abstract 1612: Molecular analysis of clinically actionable gene alterations in clear cell carcinoma of the ovary using next-generation sequencing and immunohistochemical CNV analysis

Background: Ovarian clear cell carcinoma (OCCC) is more prevalent in Japan than western countries, exhibits chemoresistant phenotype and poor survival. Although several mutations in OCCC have been reported, sensitive and rapid detection about actionable gene alterations in formalin-fixed-paraffin embedded (FFPE) tissue is required for clinical usage. In this study, we aimed to investigate major eight actionable mutations using next-generaion sequencing (NGS), and CNV-associated overexpression and phosphorylation related to their pathway using immunohistochemistry (IHC) in OCCC.

Methods: Sixty-nine consecutive patients diagnosed of OCCC in our hospital were included. SNV analyses of FFPE tissues from the primary lesions were investigated using the newly-developed GeneReader NGS platform and the Actionable Insight Tumour Panel (Qiagen) with high availability to old FFPE sample, and IHC was performed using tissue microarray (TMA).

Results: Median (range) follow-up period was 46 (0-270) months. In FIGO2014 system, 43 patients (62%) were in stage I, 3 (4%) in stage II, 19 (28%) in stage III, and 4 (6%) in stage IV. Genomic DNAs could be extracted and be analyzed in NGS from 61 FFPE specimens (88%), of which median storage period was 116 (22-269) months. Somatic gene mutations were detected in seven genes of 40/61 patients; PIK3CA, 33 (54%); KRAS, 12 (20%); ERBB3, 4 (6.6%); EGFR, 4 (6.6%); BRAF, 3 (4.9%); RAF1, 1 (1.6%); ERBB2, 1 (1.6%). In comparison with Cosmic database and previous reports, PIK3CA, KRAS and BRAF mutation were detected more frequently in our cohort, that may be associated with higher performance of our deep sequencing, or with racial features of Japanese OCCC population. PIK3CA mutation was not correlated with prognosis in overall survival (OS), progression-free survival (PFS) and OS after recurrence. However, in the patients with KRAS mutation, median OS after recurrence was 5.5 months, which was significantly worse than that without the mutation (31 months, p value = 0.0274), although OS and PFS were not significantly different. KRAS mutation was positively correlated with MET, HER2 and HER3 overexpression and AKT phosphorylation in IHC.

Conclusion: We could more frequently detect several actionable gene mutations even in old FFPE specimens, which may warrant the use of deep sequencing analysis about actionable gene mutations.

Citation Format: Hiroshi Asano, Yutaka Hatanaka, Kanako C. Hatanaka, Asami Okumura, Toraji Amano, Takashi Mitamura, Tatsuya Kato, Yosuke Konno, Daisuke Endo, Kei Ihira, Ayako Nozaki, Yoshihiro Matsuno, Hidemichi Watari, Noriaki Sakuragi. Molecular analysis of clinically actionable gene alterations in clear cell carcinoma of the ovary using next-generation sequencing and immunohistochemical CNV analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1612.

Induction of anti-VEGF therapy resistance by upregulated expression of microseminoprotein (MSMP)

Anti-vascular endothelial growth factor (VEGF) therapy has demonstrated efficacy in treating human metastatic cancers, but therapeutic resistance is a practical limitation and most tumors eventually become unresponsive. To identify microenvironmental factors underlying the resistance of cancer to antiangiogenesis therapy, we conducted genomic analyses of intraperitoneal ovarian tumors in which adaptive resistance to anti-VEGF therapy (B20 antibody) developed. We found that expression of the microseminoprotein, prostate-associated (MSMP) gene was substantially upregulated in resistant compared with control tumors. MSMP secretion from cancer cells was induced by hypoxia, triggering MAPK signaling in endothelial cells to promote tube formation in vitro. Recruitment of the transcriptional repressor CCCTC-binding factor (CTCF) to the MSMP enhancer region was decreased by histone acetylation under hypoxic conditions in cancer cells. MSMP siRNA, delivered in vivo using the DOPC nanoliposomes, restored tumor sensitivity to anti-VEGF therapy. In ovarian cancer patients treated with bevacizumab, serum MSMP concentration increased significantly only in non-responders. These findings imply that MSMP inhibition combined with the use of antiangiogenesis drugs may be a new strategy to overcome resistance to antiangiogenesis therapy.

Role of CTGF in Sensitivity to Hyperthermia in Ovarian and Uterine Cancers

Even though hyperthermia is a promising treatment for cancer, the relationship between specific temperatures and clinical benefits and predictors of sensitivity of cancer to hyperthermia is poorly understood. Ovarian and uterine tumors have diverse hyperthermia sensitivities. Integrative analyses of the specific gene signatures and the differences in response to hyperthermia between hyperthermia-sensitive and -resistant cancer cells identified CTGF as a key regulator of sensitivity. CTGF silencing sensitized resistant cells to hyperthermia. CTGF small interfering RNA (siRNA) treatment also sensitized resistant cancers to localized hyperthermia induced by copper sulfide nanoparticles and near-infrared laser in orthotopic ovarian cancer models. CTGF silencing aggravated energy stress induced by hyperthermia and enhanced apoptosis of hyperthermia-resistant cancers.

The Anti-tumor Effect of Cabozantinib on Ovarian Clear Cell Carcinoma In Vitro and In Vivo

BACKGROUND

Several reports have shown that the overexpression of the MET proto-oncogene, receptor tyrosine kinase (MET), was more frequently observed in clear cell carcinoma (CCC) than in non-CCC. We evaluated the antitumor activity of cabozantinib, that targets MET.

MATERIALS AND METHODS

A gene expression analysis of tumors from human ovarian cancers was carried out by transcriptome sequencing. An in vitro 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide assay (MTT assay) and in vivo experiments were performed to determine the activity of cabozantinib.

RESULTS

The MET levels were higher in tumors with CCC than high-grade serous carcinoma (2.2-fold). Cabozantinib inhibited cell viability and phosphorylation of AKT and MAPK under the treatment of hepatocyte growth factor in RMG-I CCC cells. The tumors removed from mice given cabozantinib of 10 mg/kg weighed 70% less than control on day 15, and the immunohistochemical reactivity of phosphorylated MET was reduced compared with control mice.

CONCLUSION

Cabozantinib contributes to tumor reduction, and phosphorylated MET represents an attractive target of CCC.

Abstract LB-323: Comparative miRNA microarray profiling indicates miR-363 promotes chemoresistance in ovarian cancer cells by targeting the Hippo member, LATS2

Ovarian cancer is the most aggressive female reproductive tract tumours. Taxane (TX) is widely used for ovarian cancer treatment. However, ovarian cancer often acquire chemoresistance. MicroRNAs (miR) have been reported to regulate many tumours’ chemoresistance. Here, we investigated the comparative microRNA expression profile between the ovarian cancer cells and their taxane-resistant counterpart, KF-TX to get novel markers for taxane resistance in ovarian cancer. The array data revealed that miR-486, miR143,miR145 and miR363 are the most upregulated miRNAs in association with TX resistance. However, miR-155, miR-100, miR-31 and miR-629 are the most significantly downregulated miRNAs after resistance development. We then focused on the role of miR-363 in chemoresistance of the ovarian cancer. qRT-PCR indicated that miR-363 was upregulated in KF-TX cells, confirming the array data, and introduction of miR-363 into sensitive ovarian cancer cells confers TX-resistance and significantly inhibited the expression of the Hippo member, LATS2, as indicated by viability, clonogenic assays and expression analysis. Furthermore, we validated the role of LATS2 in the TX-response by sh-based silencing, which also confers TX-resistance in the responsive ovarian cancer cells. On the other hand, specific inhibitor against miR-363 restored the response to TX. In addition, miR-363 was found to bind to the 3′-UTR of LATS2 mRNA, confirming that miR-363 directly targets LATS2 as indicated by dual luciferase assay. RT-PCR-based evaluation of miR-363 in a panel of human ovarian tumours revealed its upregulation in most of the tumour tissues identified as resistant while downregulation of the same gene in most of the tissues identified as sensitive ones. Moreover, higher levels of miR-363 in human ovarian cancer specimens were significantly correlated with TX chemoresistance and poor prognosis. Taken together, our study reveals the involvement of miR-363 in chemoresistance by targeting LATS2 in ovarian cancers, raising the possibility that combination therapy with a miR-363 inhibitor and TX may increase TX efficacy and reduce the chance of TX-resistance.

Note: This abstract was not presented at the meeting.

Citation Format: Noriaki Sakuragi, Mohamed Kamel Farah, Zeinab Mohamed, Safwat Okasha, Hidemichi Watari, Takashi Mitamura, sherif El Khamisy, Yusuke Ohba. Comparative miRNA microarray profiling indicates miR-363 promotes chemoresistance in ovarian cancer cells by targeting the Hippo member, LATS2 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-323. doi:10.1158/1538-7445.AM2017-LB-323

Abstract 4144: Role of CTGF in hyperthermia resistance in ovarian and uterine cancers

Objective. Even though hyperthermia is a promising treatment for cancer, multiple obstacles remain to be cleared. Among these, the tumor temperatures that must be reached for obtaining clinical efficacy are undefined. The purpose of our study was to identify the molecular predictors of response to hyperthermia in ovarian and uterine cancers.

Methods. The temperature transition in tumors during hyperthermic intraperitoneal chemotherapy (HIPEC) in ovarian cancer patients was examined. To evaluate sensitivity to hyperthermia, 10 ovarian and uterine cancer cells were treated with hyperthermia and determined median lethal temperature 50 (LT50). An integrative analysis was performed to identify molecules associated with hyperthermia resistance by comparison with gene and protein expression between hyperthermia-resistant (HTR) and -sensitive (HTS) cells. The effect of identified gene silencing on sensitization to hyperthermia and tumor growth in orthotopic models of ovarian cancers by using liposomal siRNA and local hyperthermia by NIR and CuS nanoparticles.

Results. The temperature during HIPEC in human tumors was &lt; 40°C even though the perfusion temperature at the entrance was maintained at 42.5°C. Based on LT50, we identified 5 cell lines as HTR (SKOV3, HeyA8, KLE, PEO4, and ES2; LT50 47.5 ± 0.3°C) and 5 as HTS (A2780, A2780CP20, Hec-1A, SKKUT-2, and ISHIKAWA; LT50 45.5 ± 0.2°C). Gene expression studies identified 15 genes that were highly upregulated in HTR compared with HTS cells. Proteomic analyses showed that glucose metabolism-related proteins were down-regulated in SKOV3 cells after hyperthermia. Pathway analysis indicated that FN1, SGK1, and CTGF among the 15 genes were potentially connected with glucose metabolism-related proteins. CTGF siRNA sensitized HTR cells to hyperthermia. The combination of CTGF silencing and local hyperthermia significantly inhibited tumor growth and metastasis in HeyA8 and SKOV3 orthotopic models.

Conclusion. Collectively, we identified CTGF as a key target for enhancing response to hyperthermia in ovarian and uterine cancers.

Citation Format: Hiroto Hatakeyama, Sherry Y. Wu, Yasmin A. Lyons, Sunila Pradeep, Wanqin Wang, Qian Huang, Karem A. Court, Tao Liu, Song Nie, Cristian Rodriguez-Aguayo, Fangrong Shen, Yan Huang, Takeshi Hisamatsu, Takashi Mitamura, Piotr L. Dorniak, Lingegowda S. Mangala, Marco Petrillo, Madeline Torres-Lugo, Karin D. Rodland, Anna Fagotti, Gabriel Lopez-Berestein, Chun Li, Anil K. Sood. Role of CTGF in hyperthermia resistance in ovarian and uterine cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4144. doi:10.1158/1538-7445.AM2017-4144

Abstract 473: PRKRA/PACT expression promotes chemoresistance in mucinous ovarian cancer

Purpose: To investigate the mechanisms of chemotherapy resistance and developing strategies to enhance therapeutic responses in mucinous ovarian cancer (MOC).

Experimental design: We carried out a kinome-based siRNA screen using human MOC to identify novel targets to enhance the efficacy of chemotherapy in MOC cell lines. In vitro and in vivo validation studies were carried out using MOC models. We specifically interrogated the role of PRKRA in MOC based on our screen results.

Results: Among the 939 genes in the screen, we focused on PRKRA/PACT because it was one of the top 5 target genes that exhibited the greatest extent of synthetic lethality in the target gene-siRNA plus oxaliplatin group relative to the target gene-siRNA group. The combination of oxaliplatin plus siPRKRA treatment resulted in significantly reduced cell viability compared with oxaliplatin plus control siRNA in RMUG-L-ip1 or RMUG-S-ip1 MOC cells (p&lt;0.001), while knockdown of PRKRA did not result in a significant change in cell viability compared with the control. We also observed a 2.1-fold increase in cell apoptosis in vitro after treatment with oxaliplatin plus siPRKRA in both MOC cells (p&lt;0.05). Using orthotopic mouse models of MOC, we observed an 88% reduction (p&lt;0.01) in tumor weight and 75% reduction in the number of tumor nodules (p&lt;0.01) in the siPRKRA plus oxaliplatin group compared with the control siRNA plus oxaliplatin group. PRKRA expression in human MOC was significantly higher relative to high-grade serous ovarian tumors as evaluated by immunohistochemistry. Furthermore, we found that the interaction between PACT and Dicer can regulate maturation of microRNA. In particular, mature-miR-515-3p was found to be inhibited by the interaction between PACT and Dicer. Expression of miR-515-3p promotes chemosensitivity in MOC by targeting the mRNA of the anti-apoptotic gene AXL.

Conclusion: The PRKRA/PACT axis represents an important therapeutic opportunity in MOC for enhancing oxaliplatin efficacy.

Citation Format: Takeshi Hisamatsu, Michael McGuire, Sherry Y. Wu, Rajesha Rupaimoole, Sunila Pradeep, Kyunghee Noh, Justyna Filant, Jean M. Hansen, Yasmin Lyons, Kshipra M. Gharpure, Archana S. Nagaraja, Lingegowda S. Mangala, Takashi Mitamura, Cristian Rodriguez-Aguayo, Geoffrey A. Bartholomeusz, Cristina Ivan, Ju-Seong Lee, Koji Matsuo, Michael Frumovitz, Kwong K. Wong, Gabriel Lopez-Berestein, Anil K. Sood. PRKRA/PACT expression promotes chemoresistance in mucinous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 473. doi:10.1158/1538-7445.AM2017-473

Control of Pseudomonas mastitis on a large dairy farm by using slightly acidic electrolyzed water

The disinfection effect of slightly acidic electrolyzed water (SAEW) use in a farm where Pseudomonas mastitis has spread was evaluated. Despite the application of antibiotic therapy and complete cessation of milking infected quarters, numerous new and recurrent Pseudomonas aeruginosa clinical mastitis infections (5.8-7.1% of clinical mastitis cases) occurred on the farm from 2003 to 2005. Procedural changes and equipment modifications did not improve environmental contamination or the incidence of Pseudomonas mastitis. To more thoroughly decontaminate the milking parlor, an SAEW system was installed in 2006. All milking equipment and the parlor environment were sterilized with SAEW (pH 5-6.5, available chlorine 12 parts per million) before and during milking time. After adopting the SAEW system, the incidence of clinical and subclinical Pseudomonas mastitis cases decreased significantly (P < 0.0001) and disappeared. These findings suggest that SAEW effectively reduced the incidence of mastitis in a herd contaminated by Pseudomonas species. This is the first report to demonstrate the effectiveness of disinfection by SAEW against mastitis pathogens in the environment.

Role of Increased n-acetylaspartate Levels in Cancer

BACKGROUND

The clinical and biological effects of metabolic alterations in cancer are not fully understood.

METHODS

In high-grade serous ovarian cancer (HGSOC) samples (n = 101), over 170 metabolites were profiled and compared with normal ovarian tissues (n = 15). To determine NAT8L gene expression across different cancer types, we analyzed the RNA expression of cancer types using RNASeqV2 data available from the open access The Cancer Genome Atlas (TCGA) website (http://www.cbioportal.org/public-portal/). Using NAT8L siRNA, molecular techniques and histological analysis, we determined cancer cell viability, proliferation, apoptosis, and tumor growth in in vitro and in vivo (n = 6-10 mice/group) settings. Data were analyzed with the Student's t test and Kaplan-Meier analysis. Statistical tests were two-sided.

RESULTS

Patients with high levels of tumoral NAA and its biosynthetic enzyme, aspartate N-acetyltransferase (NAT8L), had worse overall survival than patients with low levels of NAA and NAT8L. The overall survival duration of patients with higher-than-median NAA levels (3.6 years) was lower than that of patients with lower-than-median NAA levels (5.1 years, P = .03). High NAT8L gene expression in other cancers (melanoma, renal cell, breast, colon, and uterine cancers) was associated with worse overall survival. NAT8L silencing reduced cancer cell viability (HEYA8: control siRNA 90.61% ± 2.53, NAT8L siRNA 39.43% ± 3.00, P < .001; A2780: control siRNA 90.59% ± 2.53, NAT8L siRNA 7.44% ± 1.71, P < .001) and proliferation (HEYA8: control siRNA 74.83% ± 0.92, NAT8L siRNA 55.70% ± 1.54, P < .001; A2780: control siRNA 50.17% ± 4.13, NAT8L siRNA 26.52% ± 3.70, P < .001), which was rescued by addition of NAA. In orthotopic mouse models (ovarian cancer and melanoma), NAT8L silencing reduced tumor growth statistically significantly (A2780: control siRNA 0.52 g ± 0.15, NAT8L siRNA 0.08 g ± 0.17, P < .001; HEYA8: control siRNA 0.79 g ± 0.42, NAT8L siRNA 0.24 g ± 0.18, P = .008, A375-SM: control siRNA 0.55 g ± 0.22, NAT8L siRNA 0.21 g ± 0.17 g, P = .001). NAT8L silencing downregulated the anti-apoptotic pathway, which was mediated through FOXM1.

CONCLUSION

These findings indicate that the NAA pathway has a prominent role in promoting tumor growth and represents a valuable target for anticancer therapy.Altered energy metabolism is a hallmark of cancer (1). Proliferating cancer cells have much greater metabolic requirements than nonproliferating differentiated cells (2,3). Moreover, altered cancer metabolism elevates unique metabolic intermediates, which can promote cancer survival and progression (4,5). Furthermore, emerging evidence suggests that proliferating cancer cells exploit alternative metabolic pathways to meet their high demand for energy and to accumulate biomass (6-8).

Prediction of anti-angiogenesis escape

Many clinical trials have demonstrated the benefit of anti-angiogenesis therapy in the treatment of gynecologic cancer. However, these benefits have often been in terms of progression-free rather than overall survival and in some cases, the magnitude of benefit demonstrated in the pivotal phase 3 trials has been disappointing when compared with the percentage of patients who responded in earlier phase 2 trials. Two potential explanations for this are the current inability to stratify patients according to chance of benefit and the development of resistance mechanisms within the tumor. In this article, we review the prediction of response and the proposed resistance and escape mechanisms involved in anti-angiogenesis therapy, including the up-regulation of alternative proangiogenic pathways, vascular co-option, and resistance to hypoxia. These insights may offer a personalized strategy for anti-angiogenesis therapy and help us to consider the best selection of other therapies that should be combined with anti-angiogenesis therapy to improve the outcome of patients with gynecologic cancer.

MicroRNA-101 targets EZH2, MCL-1 and FOS to suppress proliferation, invasion and stem cell-like phenotype of aggressive endometrial cancer cells

MicroRNA-101 has been implicated as a tumor suppressor miRNA in human tumors. However, its potential functional impact and the underlying mechanisms in endometrial cancer progression have not been determined. Here, we report that in aggressive endometrial cancer cells, re-expression of microRNA-101 leads to inhibition of cell proliferation and induction of apoptosis and senescence. Ectopic overexpression of microRNA-101 attenuates the epithelial-mesenchymal transition-associated cancer cell migration and invasion, abrogates the sphere-forming capacity and enhances chemosensitivity to paclitaxel. Algorithm and microarray-based strategies identifies potential microRNA-101 targets. Among these, we validated EZH2, MCL-1 and FOS as direct targets of miR-101 and silencing of these genes mimics the tumor suppressive effects observed on promoting microRNA-101 function. Importantly, further results suggest an inverse correlation between low miR-101 and high EZH2, MCL-1 and FOS expression in EC specimens. We conclude that, as a crucial tumor suppressor, microRNA-101 suppresses cell proliferation, invasiveness and self-renewal in aggressive endometrial cancer cells via modulating multiple critical oncogenes. The microRNA-101-EZH2/MCL-1/FOS axis is a potential therapeutic target for endometrial cancer.

Acceptance and Commitment Therapy for "Taro," a Japanese Client with Chronic Depression: A Replicated Treatment-Evaluation

This single case study examined the effectiveness of Acceptance and Commitment Therapy (ACT) for "Taro," a chronically depressed Japanese man in his thirties. After his baseline functioning was recorded, 9 one-hour weekly sessions, 3 biweekly one-hour booster sessions (bibliotherapy using ACT self-help reading materials), and then 4 monthly follow-up sessions, were conducted. The study examines the outcome of each of the treatment components, which were introduced in a step-by-step manner. In addition, the effects of interventions directed at each core process were also tested. As a result, the effectiveness of ACT was demonstrated with a chronically depressed Japanese client. The effectiveness of interventions was remarkably high during weekly therapy until the booster sessions; in the follow-up stage previous gains were first maintained, but then showed some regression as the client's job situation deteriorated. Future directions include the identification of factors that maintain an increase in the effectiveness of ACT interventions. 

P18/Stathmin1 is regulated by miR-31 in ovarian cancer in response to taxane

MicroRNAs (miRNAs) have been reported to regulate the development of chemoresistance in many tumors. Stathmin 1 (STMN1) is a microtubule-depolymerizing molecule, involved in chemo-response; however, the mechanism of its regulation is unknown. Herein, the immunohistochemical study indicated significant upregulation of the STMN1 in the ovarian cancer tissues defined as resistant tumors compared with those defined as responsive tumors. STMN1 level elevated in the chemoresistant ovarian cancer cells, KF-TX, compared with the parental, KF, ones. Targeting STMN1 by siRNA restored taxane-sensitivity of KF-TX cells. Screening miRNA profiles from KF/KF-TX cellular set followed by bioinformatics-based prediction, revealed that miR-31 could be a possible regulator of STMN1. Down-modulation of miR-31 was verified by quantitative RT-PCR in the cellular set used. Overexpression of miR-31 in KF-TX cells (KF-TX-miR-31) significantly restored chemo-response and reduced STMN1 expression as well. STMN1 reduction-associated cellular characteristics such as enhanced microtubule polymerization and stability, as indicated by acetylated tubulin quantification, confocal visualization, and G2 phase delay, were observed in KF-TX-miR-31 cells, indicating the functional reduction of STMN1. miR-31 suppressed the luciferase activity in reporter construct containing the STMN1 3'-untranslated region (3'-UTR), confirming that miR-31 directly targets STMN1. miR-31 has therapeutic potency when introduced into ovarian cancer, in combination with taxane.

Lymphadenectomy can be omitted for low-risk endometrial cancer based on preoperative assessments

OBJECTIVE

According to the International Federation of Gynecology and Obstetrics staging, some surgeons perform lymphadenectomy in all patients with early stage endometrial cancer to enable the accurate staging. However, there are some risks to lymphadenectomy such as lower limb lymphedema. The aim of this study was to investigate whether preoperative assessment is useful to select the patients in whom lymphadenectomy can be safely omitted.

METHODS

We evaluated the risk of lymph node metastasis (LNM) using LNM score (histological grade, tumor volume measured in magnetic resonance imaging [MRI], and serum CA-125), myometrial invasion and extrautrerine spread assessed by MRI. Fifty-six patients of which LNM score was 0 and myometrial invasion was less than 50% were consecutively enrolled in the study in which a lymphadenectomy was initially intended not to perform. We analyzed several histological findings and investigated the recurrence rate and overall survival.

RESULTS

Fifty-one patients underwent surgery without lymphadenectomy. Five (8.9%) who had obvious myometrial invasion intraoperatively underwent systematic lymphadenectomy. One (1.8%) with endometrial cancer which was considered to arise from adenomyosis had para-aortic LNM. Negative predictive value of deep myometrial invasion was 96.4% (54/56). During the mean follow-up period of 55 months, one patient with deep myometrial invasion who refused an adjuvant therapy had tumor recurrence. The overall survival rate was 100% during the study period.

CONCLUSION

This preoperative assessment is useful to select the early stage endometrial cancer patients without risk of LNM and to safely omit lymphadenectomy.

Multivariate prognostic analysis of adenocarcinoma of the uterine cervix treated with radical hysterectomy and systematic lymphadenectomy

Objective

The aim of this study was to investigate the prognostic factors and treatment outcome of patients with adenocarcinoma of the uterine cervix who underwent radical hysterectomy with systematic lymphadenectomy.

Methods

A total of 130 patients with stage IB to IIB cervical adenocarcinoma treated with hysterectomy and systematic lymphadenectomy from 1982 to 2005 were retrospectively analyzed. Clinicopathological data including age, stage, tumor size, the number of positive node sites, lymphovascular space invasion, parametrial invasion, deep stromal invasion (>2/3 thickness), corpus invasion, vaginal infiltration, and ovarian metastasis, adjuvant therapy, and survival were collected and Cox regression analysis was used to determine independent prognostic factors.

Results

An estimated five-year survival rate of stage IB1 was 96.6%, 75.0% in stage IB2, 100% in stage IIA, and 52.8% in stage IIB. Prognosis of patients with one positive-node site is similar to that of those with negative-node. Prognosis of patients with multiple positive-node sites was significantly poorer than that of negative and one positive-node site. Multivariate analysis revealed that lymph node metastasis, lymphovascular space invasion, and parametrial invasion were independent prognostic factors for cervical adenocarcinoma. Survival of patients with cervical adenocarcinoma was stratified into three groups by the combination of three independent prognostic factors.

Conclusion

Lymph node metastasis, lymphovascular space invasion, and parametrial invasion were shown to be independent prognostic factors for cervical adenocarcinoma treated with hysterectomy and systematic lymphadenectomy.

Downregulation of miRNA-31 induces taxane resistance in ovarian cancer cells through increase of receptor tyrosine kinase MET

Ovarian cancer is one of the most aggressive female reproductive tract tumors. Paclitaxel (PTX) is widely used for the treatment of ovarian cancer. However, ovarian cancers often acquire chemotherapeutic resistance to this agent. We investigated the mechanism of chemoresistance by analysis of microRNAs using the ovarian cancer cell line KFr13 and its PTX-resistant derivative (KFr13Tx). We found that miR-31 was downregulated in KFr13Tx cells, and that re-introduction of miR31 re-sensitized them to PTX both in vitro and in vivo. miR-31 was found to bind to the 3′-UTR of mRNA of MET, and the decrease in MET correlated to higher sensitivity to PTX. Furthermore, co-treatment of KFr13Tx cells with MET inhibitors sensitized the tumor cells to PTX both in vitro and in vivo. In addition, lower levels of miR31 and higher expression of MET in human ovarian cancer specimens were significantly correlated with PTX chemoresistance and poor prognosis. This study demonstrated miR31-dependent regulation of MET for chemoresistance of ovarian cancer, raising the possibility that combination therapy with a MET inhibitor and PTX will increase PTX efficacy.

New revised FIGO 2008 staging system for endometrial cancer produces better discrimination in survival compared with the 1988 staging system

BACKGROUND AND OBJECTIVES

The aim of this study was to analyze the stage migration and survival of endometrial cancer by the revised FIGO 2008 staging system compared with the 1988 staging system.

METHODS

A total of 355 patients with endometrial cancer, who underwent complete surgical staging, were enrolled. We compared the surgical stages and survival by FIGO 1988 staging system with those by FIGO 2008 staging system.

RESULTS

2008 FIGO staging system resulted in an increase of stage I patients and decrease of stage II and IIIa patients. The 5-year overall survival (OS) rates for patients with 2008 FIGO stage IA and IB disease were 98.2% and 91.9%, respectively (P = 0.004). Five-year OS rate of new stage II (82.6%) was significantly worse than that of new stage IA (98.2%, P = 0.003). Patients with positive washing cytology alone revealed a 5-year OS rate similar to that of patients with new stage IIIA disease (96.2% vs. 90.9%, respectively; P = 0.53). The 5-year OS rate for patients with stage IIIC1 disease was improved compared with that for patients with stage IIIC2 disease (85.7% vs. 63.0%, respectively; P = 0.08).

CONCLUSION

New revised FIGO 2008 staging system for endometrial cancer produced better discrimination in OS outcomes compared with the 1988 system.

Clusterin is a potential molecular predictor for ovarian cancer patient's survival: targeting clusterin improves response to paclitaxel

Background

Clusterin is a cytoprotective chaperone protein involved in numerous physiological processes, carcinogenesis, tumor growth and tissue remodelling. The purpose of this study was to investigate whether clusterin (CLU), an antiapoptotic molecule, could be a potential predictor molecule for ovarian cancer and whether or not targeting this molecule can improve survival of ovarian cancer patients.

Methods

Clusterin expression was compared between ten primary and their recurrent tumors from same patients immunohistochemically. We analyzed prognostic significance of CLU expression in another 47 ovarian cancer tissue samples by immunohistochemistry. We used small interference RNA to knock down CLU in the chemo-resistant ovarian cancer cell lines. KF-TX and SKOV-3-TX, paclitaxel-resistant ovarian cancer cells, were established from parental KF and SKOV-3 chemo-sensitive cell lines, respectively. Either siRNA or second generation antisense oligodeoxynucleotide against CLU (OGX-011), which is currently evaluated in clinical phase II trials in other cancer s, was used to modulate sensitivity to paclitaxel (TX) in ovarian cancer cells in vitro. Cellular viability assay, FACS analysis and annexin V staining were used to evaluate the comparative effect of CLU knocking down in ovarian cancer cells.

Results

Immunohistochemical analysis of CLU expression in primary ovarian cancer tissue specimens and their recurrent counterparts from same patients demonstrated higher expression of CLU in the recurrent resistant tumors compared with their primary tumors. High expression of CLU by immunohistochemistry among 47 surgical tissue specimens of early-stage (stage I/II) ovarian cancer, who underwent complete cytoreduction as a primary surgery, significantly related to poor survival, while none of other clinicopathological factors analyzed were related to survival in this patient cohort. Secretory CLU (s-CLU; 60 KDa) expression was upregulated in TX-resistant ovarian cancer cells compared to parental cells. Transfection of siRNA or OGX-011 clearly reduced CLU expression. Cell viability assay, FACS analysis and annexin V staining demonstrated that targeting CLU expression by siRNA or OGX-011 sensitized ovarian cancer cells to TX.

Conclusion

We conclude that CLU could be a potential molecular target to predict survival while targeting this s-CLU may improve survival of patients with ovarian cancer.

Clinical efficacy of paclitaxel/cisplatin as an adjuvant chemotherapy for patients with cervical cancer who underwent radical hysterectomy and systematic lymphadenectomy

BACKGROUND AND OBJECTIVES

The aim of this study was to compare the clinical efficacy of paclitaxel/cisplatin (TP) as an adjuvant chemotherapy to adjuvant radiotherapy (RT) after radical hysterectomy and systematic lymphadenectomy for patients with cervical cancer.

METHODS

A total of 125 patients with early-stage cervical cancer, who underwent radical hysterectomy, and received adjuvant therapy due to recurrent risk factors were retrospectively analyzed. Forty-nine patients were treated with RT, and 32 received paclitaxel/cisplatin (TP) for three to six cycles at 4-week interval. Survival and postoperative complications were compared between two modalities.

RESULTS

There was no significant difference of 3-year disease-free survival between two groups (P = 0.23), while significantly better 3-year overall survival in TP group than RT group (P = 0.02). Seven of 32 patients (21.9%) treated with adjuvant TP, 16 of 49 patients (32.7%) treated with RT showed disease recurrence. Median of survival time after recurrence in RT group and TP group was 8.5 months, 12.0 months, respectively. Postoperative bowel obstruction was significantly more frequent in the RT group compared to the TP group (P = 0.01).

CONCLUSIONS

Postoperative chemotherapy using TP might be more beneficial for survival than adjuvant RT and can reduce postoperative complications for cervical cancer patients treated with radical hysterectomy.

Multivariate survival analysis of the patients with recurrent endometrial cancer

Objective

Few studies on the prognosticators of the patients with recurrent endometrial cancer after relapse have been reported in the literature. The aim of this study was to determine the prognosticators after relapse in patients with recurrent endometrial cancer who underwent primary complete cytoreductive surgery and adjuvant chemotherapy.

Methods

Thirty-five patients with recurrent endometrial cancer were included in this retrospective analysis. The prognostic significance of several clinicopathological factors including histologic type, risk for recurrence, time to relapse after primary surgery, number of relapse sites, site of relapse, treatment modality, and complete resection of recurrent tumors were evaluated. Survival analyses were performed by Kaplan-Meier curves and the log-rank test. Independent prognostic factors were determined by multivariate Cox regression analysis.

Results

Among the clinicopathological factors analyzed, histologic type (p=0.04), time to relapse after primary surgery (p=0.03), and the number of relapse sites (p=0.03) were significantly related to survival after relapse. Multivariate analysis revealed that time to relapse after primary surgery (hazard ratio, 6.8; p=0.004) and the number of relapse sites (hazard ratio, 11.1; p=0.002) were independent prognostic factors for survival after relapse. Survival after relapse could be stratified into three groups by the combination of two independent prognostic factors.

Conclusion

We conclude that time to relapse after primary surgery, and the number of relapse sites were independent prognostic factors for survival after relapse in patients with recurrent endometrial cancer.

Inhibitory potency of tacrolimus ointment on skin tumor induction in a mouse model of an initiation-promotion skin tumor

Tacrolimus is a macrolide immunosuppressive agent, and tacrolimus ointment has been used as therapy for atopic dermatitis worldwide. Given that the immunosuppressive action of tacrolimus raises at least the theoretical potential for an increased risk of skin cancer, accurate assessment of the risk of developing skin cancer by tacrolimus ointment is necessary. The objective of the present study is to investigate the skin tumorigenic potential of commercially available tacrolimus ointment. We conducted a skin carcinogenicity study using an initiation-promotion (I/P) mouse model. Our study consisted of six groups (26 mice/group): sham control, absorptive ointment (AO), macrogol ointment (MO), tacrolimus ointment (TO) vehicle control, TO 0.03%, and TO 0.1%. Following a single administration of 7,12-dimethylbenz[α] anthracene (DMBA) to the dorsal skin of mice as an initiator, 12-O-tetra-decanoylphorbol-13-acetate (TPA) as a promoter and the test drugs were topically administered for 18 weeks. The incidence of skin hyperplasia in the TO 0.03% and TO 0.1% groups was reduced compared with both control groups (P < 0.05). Further, the incidence of skin neoplasia in the TO 0.03% (P < 0.05) and TO 0.1% groups (P < 0.01) was reduced in a dose-dependent manner compared with the sham control group. Tumor promotion effects on skin carcinogenesis were observed in the AO group, whereas inhibitory effects were observed in the MO group. TO 0.03% and TO 0.1% dose-dependently inhibit tumor induction in an I/P mouse model of skin tumors.

Survival and prognosticators of node-positive cervical cancer patients treated with radical hysterectomy and systematic lymphadenectomy

OBJECTIVE

Lymph node metastasis (LNM) is known to be the most important prognostic factor in cervical cancer. We analyzed the number of positive lymph nodes and other clinicopathological factors as prognostic factors for survival in node-positive patients with cervical cancer.

METHODS

Node-positive cervical cancer patients (n = 108) who underwent radical hysterectomy and systematic lymphadenectomy in Hokkaido University Hospital from 1982 to 2002 were enrolled. Clinicopathological data including age, stage, histologic subtype, and the number of LNM sites were collected. The main outcome was the overall survival (OS) rate for Stage Ib-IIb patients treated with surgery and postoperative radiotherapy.

RESULTS

The 5-year OS rate of patients with 1 positive node was 93.3%, that for 2 nodes was 77.3%, for 3 nodes it was 33.3%, and for 4 or more it was 13.8%. The OS rate of patients with 1 or 2 LNM sites was significantly better than that for patients with more than 2 LNM sites. The OS rate of patients with adenocarcinoma (Ad) (28.6%) was significantly lower than that for patients with other histologic subtypes (squamous cell carcinoma; 66.7%, adenosquamous carcinoma; 75.0%, p = 0.0003). Multivariate analysis revealed that >2 LNM sites and Ad were independent prognostic factors for survival. The 5-year OS rate of patients with 1 or 2 LNM sites was 86.8%, a more favorable prognosis than the OS rates in other reports.

CONCLUSION

More than two LNM sites and adenocarcinoma were independent prognostic factors for node-positive patients with cervical cancer.

ON THE NYMPH AND PROSOPON OF THE TSUTSUGAMUSHI, LEPTOTROMBIDIUM AKAMUSHI, N. SP. (TROMBIDIUM AKAMUSHI BRUMPT), CARRIER OF THE TSUTSUGAMUSHI DISEASE

Nomenclature. As mentioned above, the prosopon and the nymph of the tsutsugamushi have many characteristics which distinguish it from the other trombidia. These are the pale color and small size of the body, delicacy of the skin, the conspicuous constriction between the cephalothoracic region and the abdomen, rudimentary eyes and tracheal openings, absence of tracheal capillaries, etc. The fact that the thumb or the appendage of the palpus does not start from the side of the fourth joint of the latter but from its end, is another charac teristic which does not occur in other trombidia. From the biological point of view two facts should be mentioned; i.e., the adult female does not deposit eggs in heaps, and in contrast to those of other species, the larvaæ hatch out all through the year and feed on mammals. From these characteristics running through all the stages of development, we believe that we are justified in claiming a new genus for the tsutsugamushi. We therefore propose to change the scientific name given to this mite by Brumpt in 1910, Trombidium akamushi, and to introduce instead, according to the suggestion of Drs. Goto and Watase, the name Leptotrombidium akamushi. Determinaton of Leptotrombidium akamushi, N. Sp. Prosopon and Nymph. 1. Pale color. 2. Delicacy of the skin. 3. Distinct constriction between the cephalothoracic region and the abdomen. 4. Rudimentary, sessile eyes. 5. Indistinctnes of tracheal openings. 6. Absence of tracheal capillaries. 7. Crista abruptly widened at the end. 8. One palpal claw. Larva. 1. One scutum. 2. Round pinacles. 3. Legs, six joints, not counting the coxa. 4. Haris on the coza: one each on Joints 1, 2, and 3. 5. Hairs on the scutum, including two tactile hairs, seven; one is in the median line. Specific Determination of Leptotrombidium akamushi, N. Sp. (Trombidium akamushi Brumpt, 1910). Prosopon. 1. Small size 2. Three pairs of sucking discs on the external genitalia. 3. Hairs of the body feathered, club-shaped at the end, and the colorless. 4. The appendage of the palpus tapes distinctly towards the end. Nymph. 1. The size of the body is smaller thant that of the prosopon. 2. Two pairs of sucking discs on the external genitalia. There are no other distinct differences in the external morphology between the proposon and the nymph. Larva. 1. The color of the body is orange-red, but becomes paler after sucking on mammals. 2. The hairs of the body average 110 to 120 in number. 3. One pair of double eyes. 4. The sucking tube is visible when feeding on mammals (Hayashi). 5. The salivary gland is relatively large (Kawamura and Komagata). 6. The number and arrangemetn of the hairs on the legs and mouth parts correspond to the description given by Hirst. 7. The larvæ are found all through the year. 8. The larva is the carrier of tsutsugamushi disease in man.