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Abstract Background Although cervical cancer is often characterized as preventable, its incidence continues to increase in low‐ and middle‐income countries, underscoring the need to develop novel therapeutics for this disease.This study assessed the distribution of fusion genes across cancer types and used an RNA‐based classification to divide cervical cancer patients with a poor prognosis into subgroups. Material and Methods RNA sequencing of 116 patients with cervical cancer was conducted. Fusion genes were extracted using StarFusion program. To identify a high‐risk group for recurrence, 65 patients who received postoperative adjuvant therapy were subjected to non‐negative matrix factorization to identify differentially expressed genes between recurrent and nonrecurrent groups. Results We identified three cases with FGFR3‐TACC3 and one with GOPC‐ROS1 fusion genes as potential targets. A search of publicly available data from cBioPortal (21,789 cases) and the Center for Cancer Genomics and Advanced Therapeutics (32,608 cases) showed that the FGFR3 fusion is present in 1.5% and 0.6% of patients with cervical cancer, respectively. The frequency of the FGFR3 fusion gene was higher in cervical cancer than in other cancers, regardless of ethnicity. Non‐negative matrix factorization identified that the patients were classified into four Basis groups. Pathway enrichment analysis identified more extracellular matrix kinetics dysregulation in Basis 3 and more immune system dysregulation in Basis 4 than in the good prognosis group. CIBERSORT analysis showed that the fraction of M1 macrophages was lower in the poor prognosis group than in the good prognosis group. Conclusions The distribution of FGFR fusion genes in patients with cervical cancer was determined by RNA‐based analysis and used to classify patients into clinically relevant subgroups.

We first used MucoUp®, a hyaluronic acid used in endoscopic resection, as a spacer in brachytherapy. In five cervical cancer patients, MucoUp® insertion increased a 90% dose of the high-risk CTV to over 80 Gy while decreasing the dose of organs at risk. No related adverse events were observed.

Abstract Background This study aimed to clarify predictors of depressive symptoms and anxiety symptoms after cancer diagnosis among Japanese cancer survivors (CSs). Methods As part of a Japanese cancer survivorship research project commissioned by the Ministry of Health, Labour and Welfare (MHLW) of Japan, we conducted a web-based nationwide survey of CSs in 2018. We analyzed the risk factors for depressive and anxiety symptoms, as measured by the Hospital Anxiety and Depression Scale Japanese version (HADS). Results Of 1,234 Japanese CSs, mean score of HADS-depression and HADS-anxiety were 4.08 and 4.78, respectively. At the time of the study, the number of CSs with symptoms of depression and anxiety were 111 (9.0%) and 269 (21.8%), respectively. After multivariable analysis, CSs ≥ 60 years old (reference: ≤ 39 years old, odds ratios (OR): 0.39, 95%CI: 0.17–0.90) and those ≥ 10 years from cancer diagnosis (reference: 0–4 years, OR: 0.55, 95%CI: 0.32–0.96) had lower odds for depressive symptoms. And CSs ≥ 60 years old (reference: ≤ 39 years old, OR: 0.27, 95%CI: 0.15–0.49) and those ≥ 10 years from cancer diagnosis (reference: 0–4 years, OR: 0.62, 95%CI: 0.42–0.90) also had lower odds for anxiety symptoms. CSs who received chemotherapy (OR: 1.56, 95%CI: 1.10–2.20) had higher odds for anxiety symptoms. Conclusions Based on manifestation of symptoms, CSs who were younger, closer to the time of cancer diagnosis, had advanced-staged cancer, or received chemotherapy may be at higher risk for depressive or anxiety symptoms. Those CSs who have higher risk for depression and anxiety symptoms, should be followed-up more carefully for better cancer survivorship, by medical professionals, companies, and society.

Abstract Gene expression is controlled at the transcriptional and post-transcriptional levels. The TACC2 gene was known to be associated with tumors but the control of its expression is unclear. We have reported that activity of the intronic promoter p10 of TACC2 in primary lesion of endometrial cancer is indicative of lymph node metastasis among a low-risk patient group. Here, we analyze the intronic promoter derived isoforms in JHUEM-1 endometrial cancer cells, and primary tissues of endometrial cancers and normal endometrium. Full-length cDNA amplicons are produced by long-range PCR and subjected to nanopore sequencing followed by computational error correction. We identify 16 stable, 4 variable, and 9 rare exons including 3 novel exons validated independently. All variable and rare exons reside N-terminally of the TACC domain and contribute to isoform variety. We found 240 isoforms as high-confidence, supported by more than 20 reads. The large number of isoforms produced from one minor promoter indicates the post-transcriptional complexity coupled with transcription at the TACC2 locus in cancer and normal cells.

Abstract Purpose We sought dosimetric predictors of a decreasing estimated glomerular filtration rate (eGFR) in gynecological oncology patients receiving extended-field radiation therapy (EFRT). Materials and methods Between July 2012 and April 2020, 98 consecutive cervical or endometrial cancer patients underwent EFRT or whole-pelvis radiation therapy (WPRT) with concurrent cisplatin chemotherapy in our institution. To explore the effect of concurrent cisplatin chemotherapy on renal function, the renal function of the WPRT patients was examined. Of the 98 patients, 34 cervical or endometrial cancer patients underwent EFRT including extended-field intensity-modulated radiation therapy (EF-IMRT) and 64 cervical cancer patients underwent WPRT with cisplatin. Of the 34 EFRT patients, 32 underwent concurrent cisplatin chemotherapy. Excluding patients exhibiting recurrences within 6 months, 31 EFRT patients were analyzed in terms of the dose-volume kidney histograms (the percentages of kidney volumes receiving 12, 16, 20, and 24 Gy) and the post- to pre-treatment eGFR ratios. We calculated Pearson correlation coefficients between the renal dose volume and the percentage eGFR reductions of the 31 EFRT patients, and those treated via EF-IMRT. Renal dose constraint significance was evaluated using the Mann–Whitney U test. Results The eGFR value after WPRT with cisplatin remained largely unchanged for 12 months, unlike that after EFRT. In EFRT patients, a strong correlation was evident between the KV20Gy dose and the post- to pre-treatment eGFR ratio (correlation coefficients − 0.80 for all patients and − 0.74 for EF-IMRT patients). In EF-IMRT patients, the kidney volume receiving 20 Gy tended to correlate negatively with the eGFR reduction. The Mann–Whitney U test showed that patients with KV20Gy values 10% (P = 0.002). Conclusions Imposition of a severe kidney dose constraint during EF-IMRT may reduce nephrotic toxicity. Future prospective investigations of kidney-sparing EF-IMRT are required.

Abstract Background In Japan, 55.5% of breast cancer survivors (BCSs) are of working age, so various perspectives regarding return to work (RTW) after cancer diagnosis need to be considered. Therefore, this study aimed to clarify the risk factors for resignation and taking sick leave (SL) among BCSs in continued employment at the time of diagnosis. Methods A web-based retrospective cross-sectional survey was conducted on BCSs using data from a 2018 Japanese national research project (Endo-Han) commissioned by the Ministry of Health, Labour and Welfare of Japan. The subjects were women aged 18–69 years who had been diagnosed with breast cancer for the first time at least 1 year previously. The risk factors for resignation and taking SL after breast cancer diagnosis, including age at diagnosis, education level, cancer stage, surgery, chemotherapy, radiotherapy, employment status, and occupational type, were then analyzed using a logistic regression model. Results In total, 40 (14.9%) of 269 BCSs quit their jobs at least 1 year after being diagnosed with breast cancer. The results of the multivariable analysis indicated that lower education level (odds ratio [OR]: 3.802; 95% confidence interval [CI]: 1.233–11.729), taking SL (OR: 2.514; 95%CI: 1.202–5.261), and younger age at diagnosis (OR: 0.470; 95%CI: 0.221–0.998) were predictors of resignation. Of 229 patients who continued working, SL was taken by 72 (31.4%). In addition, undergoing surgery was found to be a predictor of taking SL (OR: 8.311; 95%CI: 1.007–68.621). Conclusions In total, 40 (14.9%) of 269 BCSs quit their jobs at least 1 year after being diagnosed with breast cancer. The results of this study indicated that younger age, lower education level, and taking SL were predictors of resignation after breast cancer diagnosis.

Uterine adenomyosis often co-occurs with endometriosis or leiomyoma, but little is known about its molecular underpinnings. Here, the authors show that KRAS mutations are frequent in this disease, which might reduce sensitivity to progestin treatment via epigenetic silencing of the progesterone receptor.

PurposeThis is a report of our initial experience using computed tomography (CT)-guided interstitial high dose rate (HDR) brachytherapy to treat bulky pelvic nodal metastases as a part of definitive radiotherapy.Material and methodsBetween February 2015 and April 2019, 14 cervical/endometrial cancer patients presenting with bulky pelvic node(s) underwent nodal interstitial brachytherapy boost in our institution. In total, 17 nodes were treated. The median maximum diameters of the positive nodes at the time of diagnosis and at the first nodal implant were 25 mm (range: 10–65 mm) and 16 mm (range: 9–51 mm), respectively. Dosimetry data of the lymph nodal target volume and small bowel were collected and compared using the paired-sample t-test. Treatment-related toxicities were classified using the Common Terminology Criteria for Adverse Events version 4.0.ResultsThe median follow-up time for all patients was 26 months. Local recurrence in pelvic nodes occurred in one patient (7%) after 16 months. One patient experienced grade 3 bladder bleeding, and one patient experienced grade 2 pubic bone fracture. No patient had grade 2 or greater gastrointestinal toxicity. In the dosimetric analysis, the mean nodal brachytherapy D90% in terms of the total equivalent dose of 2 Gy (EQD2) was 65.6 Gyαβ10. The mean small bowel dose (SBD)0.1cc and SBD1cc in terms of the total EQD2 were 60.4 and 56.5 Gyαβ3, respectively. Nodal D90% was significantly higher in terms of the total EQD2 than the SBD0.1cc (p = 0.003) and SBD1cc (p < 0.001). The Kaplan-Meier 2-year pelvic control estimate was 90%.ConclusionsCT-guided interstitial HDR pelvic nodal brachytherapy appears to be well tolerated with excellent local control in cervical or endometrial cancer patients with bulky pelvic nodes. This approach may offer a useful therapeutic option for unresected bulky pelvic nodes.

Abdominal myomectomy for a huge myomas, especially uterine cervical myoma, is difficult because of risks, such as intraoperative bleeding or injury to adjacent organs. Therefore, understanding of the positional relationships among a huge myoma, especially cervical or intraligamental myoma, and the vascular plexuses in the right and left cardinal ligaments is important for prevention of massive bleeding during myomectomy. While sufficiently performing preoperative assessment with pelvic examination, ultrasonography, magnetic resonance imaging (MRI), etc., surgeons should always keep in mind how they can reduce the blood loss volume, while safely and surely performing resections. For a cervical myoma of the uterus and giant uterine leiomyoma that leave no intrapelvic space and prevent palpation and identification of the uterine arteries and the internal iliac arteries, surgery can be performed safely by preoperatively placing balloon catheters in the internal iliac arteries. Hemostaic strategies for myomectomy and tips of subsequent pregnancy following myomectomy are also described.

Objective: The aim of this study was to evaluate the outcomes of neoadjuvant chemotherapy (NAC) with bevacizumab (Bev) at our institute. Materials and methods: Eleven patients with stage IIIC or IV peritoneal/ovarian cancer who underwent interval debulking surgery (IDS) after NAC with Bev between December 2014 and December 2016 were enrolled retrospectively (TCB group). As a control group, we enrolled 13 patients evaluated between December 2012 and December 2014 who underwent IDS and received NAC without Bev (TC group). Both the TCB and TC groups received combination chemotherapy consisting of paclitaxel (175 mg/m2) or docetaxel (70 mg/m2) and carboplatin (area under the curve 6 mg/mL/min) administered intravenously every 3 weeks (cycles 3–6). Results: All patients in both groups underwent IDS. There were 7 (63.6%) and 8 (61.5%) cases with stage IIIC disease and 4 (36.3%) and 5 (30.7%) with stage IV disease in the TCB and TC groups, respectively. The complete resection rate was 81.8% in the TCB group and 69.2% in the TC group. The rate of achieving either complete or optimal resection was 100% in the TCB group and 69.2% in the TC group (p = 0.043). Hematoxicity (grade 3 or higher) was observed in 9 patients (81.8%) in the TCB group and 12 (92.3%) patients in the TC group. One patient (9%) in the TCB group experienced abdominal incisional hernia due to a fascial defect. Conclusion: IDS after NAC with Bev is safe, with a similar efficacy as that after NAC without Bev. Keywords: Ovarian cancer, Neoadjuvant chemotherapy, Interval debulking surgery, Bevacizumab

Abstract Background The mortality rate of ovarian cancer is the highest among all gynecological malignancies in Japan. Ovarian tumors are classified as benign, borderline malignant, or malignant. Anticipating the histological subtype with imaging only is often difficult because of several histological subtypes of epithelial ovarian tumors (such as serous, mucinous, endometrioid, clear cell, and Brenner tumors). In addition, the majority of mucinous tumors in the ovary are metastatic. Furthermore, mucinous tumors belong to one of the two different subclasses (i.e., intestinal and seromucinous types). Ovarian seromucinous cystic tumors of borderline malignancy are infrequent and only rarely coexist with other malignant tumors. Case presentation We have reported a 53-year-old Japanese woman with anaplastic carcinoma in an ovarian seromucinous cystic tumor of borderline malignancy. Her MRI and CT analysis revealed an ovarian tumor with a mural nodule, ascites, and peritoneal dissemination. Enhanced MRI revealed that the mural nodule was enhanced. Enhanced CT analysis revealed that the lymph nodes were not swollen. Intriguingly, the mural nodule crossed the cyst wall into the cavity and onto the surface. Her laboratory data revealed high serum CA 125 level. Cumulatively, these results suggested ovarian malignancy. The patient underwent hysterectomy with bilateral salpingo-oophorectomy, omentectomy, and resection of the disseminated lesions. Lymph node biopsy was omitted because of the suggestion of enhanced CT image findings and palpation during surgery. Her postoperative specimen examination determined FIGO at least stage IIIB, and accordingly, adjuvant chemotherapy was prescribed. After 3 years of the operation, the patient is presently alive without clinical tumor recurrences. Conclusion Imaging studies with pathognomonic findings contributed to ovarian cancer diagnosis in this case. To the best of our knowledge, this is the first study in English literature to report detailed classification of mucinous borderline malignancy, seromucinous cystic, and anaplastic carcinoma in an ovarian seromucinous cystic tumor of borderline malignancy.

Isolated incisional recurrence in a patient with early-stage endometrioid carcinoma is extremely rare. The mechanism of this recurrence also remains unclear. We describe a case of an isolated incisional recurrence of endometrioid carcinoma from the uterine corpus 4 years after the primary surgery. We review the previous literature and discuss the possible mechanism of isolated incisional recurrence. A 56-year-old woman diagnosed with the International Federation of Gynecology and Obstetrics Stage IA and Grade 2 endometrioid carcinoma in the uterine corpus showed an isolated cystic mass in the abdominal wall 4 years after the primary surgery. She underwent resection of the abdominal tumor, and the pathological findings showed endometrioid carcinoma, which was the same as the primary tumor. She received chemotherapy and remained disease free 8 months after chemotherapy. Long-term follow-up is required to detect recurrence, even in patients with early-stage uterine corpus carcinoma.

Objective: Surgery for uterine cervical fibroids is difficult because of restricted surgical access and risks such as intraoperative bleeding or injury to other organs. The internal iliac artery balloon occlusion catheter (IIABOC) provides effective hemostasis for placenta previa and atonic hemorrhage, and is increasingly used in surgery for uterine fibroids for controlling intraoperative hemorrhage. We investigated the efficacy and safety of the IIABOC for controlling intraoperative bleeding in total abdominal hysterectomies (TAH) and abdominal myomectomies (AM) for large cervical fibroids. Material and methods: From 2007 to 2014, the IIABOC was used in 22 cases (12 for TAH and 10 for AM) in which cervical fibroids fully occupied the pelvic cavity. Intraoperative blood loss, operating time, sample weight, use of blood transfusion, and injury to other organs were assessed. Result: Mean blood loss, operative time, and sample weight in the IIABOC cases were 510 mL, 178 min, and 2550 g for TAH; and 727.5 mL, 157.5 min, and 1850 g for AM. Blood loss divided by sample weight in IIABOC cases was significantly lower than that in non-IIABOC cases during the same time period, for both TAH and AM. Allogeneic blood transfusion was not necessary, and complications of injury to other organs did not occur in any of the 22 cases. Conclusions: For large cervical fibroids with limited operating space, surgery was performed under bleeding control by occlusion of the internal iliac artery with an IIABOC. This technique enables control of hemorrhage and safe operative management in gynecological surgery.

Objective: To analyze the efficacy of positron emission tomography/computed tomography (PET/CT) for the diagnosis of uterine sarcoma. Materials and methods: Thirty-four patients evaluated between January 2010 and March 2015 were retrospectively enrolled. All patients in whom uterine sarcoma was suspected based on contrast-enhanced magnetic resonance imaging (MRI) findings (heterogeneous, high signal intensity on T2-weighted images and/or high intensity on T1-weighted images) underwent PET/CT for further assessment. Patients were divided into 2 groups based on postoperative pathological findings: uterine sarcoma (n = 15) and leiomyoma (n = 19). The maximum standardized uptake value (SUVmax) of all lesions was measured using PET/CT; we calculated the optimal cutoff value for diagnosing sarcoma. Results: The median SUVmax for uterine sarcoma and leiomyoma was 12 and 4.1, respectively; these values were significantly different. An SUVmax of greater than 7.5 was able to exclude leiomyoma with 80.8% sensitivity and 100% specificity (area under the curve, 95.3%). A cutoff SUVmax of 7.5 yields 100% specificity, and a cutoff SUVmax of 4.4 yields a 100% negative predictive value (NPV). The combination of PET/CT and lactate dehydrogenase (LDH) levels had a sensitivity of 86.6%, specificity of 100%, positive predictive value of 100%, and an NPV of 90.4%. No relation between histopathology or International Federation of Gynecology and Obstetrics (FIGO) stage and 18-fluoro-2-deoxy-d-glucose uptake value on PET/CT was seen. The surgical outcome trended toward a correlation with the SUVmax, although this was not statistically significant. Conclusions: In patients with MRI findings consistent with either uterine sarcoma or leiomyoma, PET/CT can decrease the false-positive rate by setting an optimal cutoff SUVmax of 7.5. Using this cutoff can avoid unnecessary surgery.

Perivascular epithelioid cell tumors (PEComas) are mesenchymal neoplasms with immunoreactivity for both melanocytic and smooth muscle markers. PEComas occur at multiple sites, and malignant PEComas can undergo metastasis, recurrence and aggressive clinical courses. Although the lung is a common metastatic site of PEComas, they usually appear as multiple nodules but rarely become cystic or cavitary. Here, we describe a female patient whose lungs manifested multiple cystic, cavity-like and nodular metastases 3 years after the resection of uterine tumors tentatively diagnosed as epithelioid smooth muscle tumors with uncertain malignant potential. This patient's subsequent pneumothorax necessitated video-assisted thoracoscopic surgery, and examination of her resected lung specimens eventually led to correcting the diagnosis, i.e., to a PEComa harboring tuberous sclerosis complex 1 (TSC1) loss-of-heterozygosity that originated in the uterus and then metastasized to the lungs. The administration of a gonadotropin-releasing hormone analogue later stabilized her clinical course. To the best of our knowledge, the present case is the first in the literature that associates PEComas with a TSC1 abnormality. Additionally, the pulmonary manifestations, including imaging appearance and pneumothorax, somewhat resembled those of lymphangioleiomyomatosis, a representative disease belonging to the PEComa family. Although PEComas are rare, clinicians, radiologists and pathologists should become aware of this disease entity, especially in the combined clinical setting of multiple cystic, cavity-like, nodular lesions on computed tomography of the chest and a past history of the tumor in the female reproductive system.

Objective: To review and evaluate drug-induced vasculitis, which is an extremely rare complication of chemotherapy. Case report: A 47-year-old woman with ovarian cancer developed aortitis during bevacizumab combination chemotherapy. Contract-enhanced CT showed concentric thickening of the descending aorta. Antibiotics were administered, but a repeat CE-CT scan showed no resolution of the aortitis. To treat the aortitis, she was started on oral prednisolone. A subsequent CE-CT scan showed no signs of aortitis. She was thus re-started on a modified chemotherapy regimen. Conclusion: Aortitis should be considered in patients receiving bevacizumab combination therapy who develop persistent fever and upper-abdominal pain. Contrast-enhanced CT is useful for detecting drug-induced aortitis. Keywords: Aortitis, Ovarian cancer, Bevacizumab, G-CSF

Study objective: The purpose of this study was to elucidate the surgical and oncological outcomes after laparoscopic surgery for endometrial cancer at our hospital. Materials and methods: Surgical outcomes, complications rates, 2-year survival rates, and recurrence rates were evaluated in 44 patients who underwent total laparoscopic hysterectomy (TLH) and 57 patients who underwent total abdominal hysterectomy (TAH) for endometrial cancer at our hospital between August 2010 and November 2013. Results: There was no significant difference between the two groups with respect to age or body mass index. More than 80% of patients in both groups had stage I cancer. In the TLH group, the histological types were endometrioid adenocarcinoma in 42 of 44 patients, carcinosarcoma in one patient, and serous adenocarcinoma in one patient. Operative times were significantly longer in the TLH group, but patients in this group had less intraoperative blood loss, shorter hospital stays, and reduced levels of postoperative pain, compared to patients in the TAH group. There were four cases of postoperative infection and one case of vessel injury in the TLH group. No patient in this group required blood transfusion or conversion to open surgery. There were recurrences in two (4.7%) patients in the TLH group (i.e., carcinosarcoma and serous adenocarcinoma) and in five (8.6%) patients in the TAH group. Conclusion: Laparoscopic surgery is safe and feasible for patients with early-stage endometrial cancer. However, patients with carcinosarcoma and other histologic types of endometrioid adenocarcinoma require special attention because of the high risk of recurrence and poor prognosis.

Coplanar extended-field intensity-modulated radiation therapy (EF-IMRT) targeting the whole-pelvic and para-aortic lymph nodes in patients with advanced cervical cancer results in impaired creatinine clearance. An improvement in renal function cannot be expected unless low-dose (approximately 10 Gy) kidney exposure is reduced. The dosimetric method should be considered during EF-IMRT planning to further reduce low-dose exposure to the kidneys. To assess the usefulness of non-coplanar EF-IMRT with kidney-avoiding beams to spare the kidneys during cervical carcinoma treatment in dosimetric analysis between non-coplanar and coplanar EF-IMRT, we compared the doses of the target organ and organs at risk, including the kidney, in 10 consecutive patients. To estimate the influence of EFRT on renal dysfunction, creatinine clearance values after treatment were also examined in 18 consecutive patients. Of these 18 patients, 10 patients who were included in the dosimetric analysis underwent extended field radiation therapy (EFRT) with concurrent chemotherapy, and eight patients underwent whole-pelvis radiation therapy with concurrent chemotherapy to treat cervical carcinoma between April 2012 and March 2015 at our institution. In the dosimetric analysis, non-coplanar EF-IMRT was effective at reducing low-dose (approximately 10 Gy) exposure to the kidneys, thus maintaining target coverage and sparing other organs at risk, such as the small bowel, rectum, and bladder, compared with coplanar EF-IMRT. Renal function in all 10 patients who underwent EFRT, including coplanar EF-IMRT (with kidney irradiation), was low after treatment, and differed significantly from that of the eight patients who underwent WPRT (no kidney irradiation) 6 months after the first day of treatment (P = 0.005). In conclusion, non-coplanar EF-IMRT should be considered in patients with advanced cervical cancer, particularly in patients with a long life expectancy or with pre-existing renal dysfunction.

The concept of targeting G1 cyclin-dependent kinases (CDKs) in breast cancer treatments is supported by the fact that the genetic ablation of Cdk4 had minimal impacts on normal cell proliferation in majority of cell types, resulting in near-normal mouse development, whereas such loss of Cdk4 completely abrogated ErbB-2/neu-induced mammary tumorigenesis in mice. In most human breast cancer tissues, another G1-regulatory CDK, CDK2, is also hyperactivated by various mechanisms and is believed to be an important therapeutic target. In this report, we provide genetic evidence that CDK2 is essential for proliferation and oncogenesis of murine mammary epithelial cells. We observed that 87% of Cdk2-null mice were protected from ErbB-2-induced mammary tumorigenesis. Mouse embryonic fibroblasts isolated from Cdk2-null mouse showed resistance to various oncogene-induced transformation. Previously, we have reported that hemizygous loss of Cdc25A, the major activator of CDK2, can also protect mice from ErbB-2-induced mammary tumorigenesis [Cancer Res (2007) 67(14): 6605–11]. Thus, we propose that CDC25A-CDK2 pathway is critical for the oncogenic action of ErbB-2 in mammary epithelial cells, in a manner similar to Cyclin D1/CDK4 pathway.