Hiroshi Matsumoto

Femoral head osteonecrosis can be caused by disruption of the systemic immune response via the toll-like receptor 4 signalling pathway

OBJECTIVESnOsteonecrosis of the femoral head is observed in patients treated with steroids. However, the pathogenesis of femoral head osteonecrosis remains unclear. We established a rat model with femoral head osteonecrosis by injecting lipopolysaccharide (LPS) and steroid, and assessed the consequences of this on femoral head histology, the systemic immune response and lipid synthesis.nnnMETHODSnMale Wistar rats were injected intravenously on days 0 and 1 with 2 mg/kg LPS and intramuscularly with 20 mg/kg methylprednisolone on days 3, 4 and 5. The animals were sacrificed 1, 2, 3 or 4 weeks after the last methylprednisolone injection. Histopathological and biochemical analyses were performed every week.nnnRESULTSnOsteonecrosis of the femoral head was observed in the rats. The plasma triglyceride concentrations had decreased significantly by weeks 2 and 3. The total plasma cholesterol concentrations had increased significantly by week 1 but then decreased significantly by week 4. The plasma concentrations of IL-1beta, IL-2, IL-4, IL-6, IL-10, GM-CSF, IFN-gamma and TNF-alpha had increased significantly by week 1. These cytokines can all be induced by toll-like receptor 4 (TLR4) signalling.nnnCONCLUSIONSnLPS and methylprednisolone induced osteonecrosis of the femoral head in rats and this was associated with a disruption of the innate immune system and lipid synthesis. These findings suggest that the TLR4 signalling pathway plays an important role in the pathogenesis of femoral head osteonecrosis.

Ethanol rapidly causes activation of JNK associated with ER stress under inhibition of ADH

Acute ethanol loading causes oxidative stress to activate cell‐death signaling via c‐Jun NH2‐terminal kinase (JNK) in livers. JNK are stimulated under conditions of endoplasmic reticulum (ER) stress which causes programmed cell death. However, no remarked cell death was observed in acute ethanol intoxication. Akt, one of the cell survival protein kinases, may be activated under ethanol loading. The aim of this study was to estimate activation of JNK and ER stress, role of ethanol metabolism on the activation, and association of JNK with Akt under acute ethanol loading using the perfused rat liver system. Activation of JNK or Akt and association of JNK and Akt with JNK interacting protein 1 were estimated by immunoprecipitation and immunoblotting. Expression of 78 kDa glucose‐regulated protein (GRP78) mRNA, a biomarker of ER stress, was detected by quantitative real‐time RT‐PCR. Activations of JNK and Akt were enhanced by co‐treatment with ethanol and a classical inhibitor of alcohol dehydrogenase (ADH). Addition of an antioxidant reduced the activation of JNK. Ethanol loading with ADH inhibition causes down‐regulation of GRP78 mRNA levels. Therefore, these findings suggest first revelation that inhibition of ethanol metabolism complicates oxidative and ER stresses produced by ethanol.

Totally laparoscopic hepatectomy exposing the major vessels

BackgroundEven during laparoscopic hepatectomy, a technique is often required to expose the major vessels, for example, in anatomical hepatectomy. We have standardized and performed such laparoscopic hepatectomy as successfully as open hepatectomy.MethodsWe divide the liver parenchyma without pre-coagulation, exposing the major vessels using CUSA. To control the bleeding, we keep the central venous pressure low and often perform Pringle’s maneuver. Over 49xa0months, we performed totally laparoscopic hepatectomies in 41 patients with the technique of exposing the major vessels. These included major hepatectomy in 7, sectorectomy in 17, segmentectomy in 14, and others in 3.ResultsThe median operative time was 361 (range 176–605) minutes, with median blood loss of 216 (range 0–1600) g. The conversion rate was 4.9xa0%. Postoperative morbidity rate was 9.8xa0% (prolonged ascites in 1, port site infection in 1, peroneal palsy in 2). Mortality was zero. The median length of hospital stay after surgery was 8 (range 5–28) days. No local recurrence was found at the time of writing.ConclusionsBy using our standardized procedure exposing the major vessels, we could raise the quality of laparoscopic hepatectomy toward the level of open hepatectomy significantly.

Recent trends in microRNA research into breast cancer with particular focus on the associations between microRNAs and intrinsic subtypes.

MicroRNAs (miRNAs) are short non-coding RNAs that regulate the function of target genes at the post-transcriptional phase. miRNAs are considered to have roles in the development, progression and metastasis of cancer. Recent studies have indicated that particular miRNA signatures are correlated with tumor aggressiveness, response to drug therapy and patient outcome in breast cancer. On the other hand, in routine clinical practice, the treatment regimens for breast cancer are determined based on the intrinsic subtype of the primary tumor. Previous studies have shown that miRNA expression profiles of each intrinsic subtypes of breast cancer differ. In hormone receptor-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer, miRNA expressions are found to be correlated with endocrine therapy resistance, progesterone receptor expression and heat shock protein activity. Some miRNAs are associated with resistance to HER2-targeted therapy and HER3 expression in HER2-positive breast cancer. In triple-negative breast cancer, miRNA expressions are found to be associated with BRCA mutations, immune system, epithelial–mesenchymal transition, cancer stem cell properties and androgen receptor expression. As it has been clarified that the expression levels and functions of miRNA differ among the various subtypes of breast cancer, and it is necessary to take account of the characteristics of each breast cancer subtype during research into the roles of miRNA in breast cancer. In addition, the discovery of the roles played by miRNAs in breast cancer might provide new opportunities for the development of novel strategies for diagnosing and treating breast cancer.

Phase II study of oral S-1 with irinotecan and bevacizumab (SIRB) as first-line therapy for patients with metastatic colorectal cancer

SummaryFluorouracil (5-FU) plus irinotecan combined with bevacizumab has significant activity in metastatic colorectal cancer (mCRC), but S-1 has become a substitute for continuous infusion of 5-FU and has a very low incidence of hand-foot syndrome. With the S-1 plus irinotecan regimen (SIR), the response rate was 62.5%, and the progression-free survival was 8.0xa0months. We report here on an update of efficacy and safety of the SIR plus bevacizumab (SIRB) regimen as first line treatment for mCRC patients. Fifty-one eligible patients with histologically confirmed advanced or recurrent colorectal cancer received this treatment. S-1 was administered orally on days 1–14 of a 21-day cycle. Patients were assigned on the basis of body surface area (BSA) to receive one of the following oral doses twice daily: 40xa0mg, 50xa0mg, or 60xa0mg. Irinotecan (150xa0mg/m2) plus bevacizumab (7.5xa0mg/kg) were administered by intravenous infusion on day 1. Safety analysis identified a grade 3/4 neutropenia rate of 26%. Other grade 3/4 toxicities were diarrhea (8%), nausea (6%), vomiting (2%), and hypertension (8%). The response rate was 67% and the median progression-free survival time was 373xa0days. The SIRB regimen appears to be highly active and well tolerated as first-line treatment for mCRC.

Sentinel lymph node biopsy without axillary dissection after an intraoperative negative histological investigation in 358 invasive breast cancer cases

BackgroundSentinel lymph node biopsy (SLNB) is an important treatment option for breast cancer patients, as it can accurately predict axillary status. Our previous study using dye with or without radioisotope showed the accuracy and sensitivity of SLNB to be 97% and 94%, respectively. Based on these results, axillary lymph node dissection (ALND) was eliminated starting in January, 1999 in patients with intraoperatively negative SLNB at our institution. The present study shows the results and outcomes of SLNB as a sole procedure for patients with invasive breast cancer.Patients and MethodsThree-hundred-fifty-four patients and 358 cases of invasive breast cancer (4 bilateral breast carcinoma) treated with SLNB alone after an intraoperative negative SLNB were studied prospectively from January 1999 to December 2001.ResultsThe number of the identified SLNs per case ranged from 1 to 8 (mean, 2.5). Of a total of 358 cases, 297 (83%) were treated with hormone therapy and/or chemotherapy, and 281 (78%) were treated with radiotherapy to the conserved breast (50 Gy ± 10 Gy boost), the axilla (50 Gy), or the both sites. After a median follow-up of 21 (range 6–42) months, no patient developed an axillary relapse. Four cases initially recurred in distant organs and one case in the conserved breast.ConclusionsOur results indicate that an intraoperative negative SLNB without further ALND may be a safe procedure when strict SLNB is performed. To better assess the safety, however, may require longer follow-up.

Prior ethanol injection promotes brain edema after traumatic brain injury

Alcohol consumption prior to traumatic brain injury (TBI) promotes morbidity and mortality although the mechanisms involved remain unclear. The morbidity and mortality caused by TBI, especially brain contusion, are known to be closely associated with brain edema. Here we examined the effects of ethanol pretreatment on brain edema, inflammatory responses, and oxidative stress after brain contusion. Male Wistar rats were given 3 g/kg ethanol intraperitoneally and 1 h later were subjected to brain contusion. The ethanol-pretreated group had a significantly decreased survival rate. Magnetic resonance imaging showed ethanol pretreatment significantly augmented the volume of cytotoxic brain edema after contusion. In the ethanol-pretreated rat, the activities of NF-kappaB and AP-1 were reduced 6 h after contusion and COX-2 mRNA expression was increased 24 h after contusion. These findings suggest that ethanol augmented cerebral edema and mortality in rats with brain contusion, possibly through actions on cell survival pathways or COX-2 expression. In addition, antioxidant treatment at 3 h post-injury significantly attenuated some markers of oxidative stress, mortality, and volume of edema at 24 h after ethanol treatment and contusion.

Experimental rat model for alcohol‐induced osteonecrosis of the femoral head

Alcohol‐induced osteonecrosis of the femoral head (ONFH) is observed in alcohol abusers and patients with alcoholic fatty liver disease. It has been reported that Toll‐like receptor 4 (TLR4) signalling plays a crucial role in the pathogenesis of alcoholic fatty liver disease. We previously reported a corticosteroid‐induced ONFH rat model, and suggested that TLR4 signalling contributes to the pathogenesis of ONFH. Thus, it is thought that the pathogenesis of alcohol‐induced ONFH is probably similar to that of corticosteroid‐induced ONFH. The aim of this study was to develop a new animal model for alcohol‐induced ONFH and to evaluate the relationship between the pro‐inflammatory response via TLRs and the development of ONFH in rats. Male Wistar rats were fed a Lieber–DeCarli liquid diet containing 5% ethanol (experimental group) or dextran (control group) for 1–24 weeks. Histopathological and biochemical analyses were performed. Feeding the ethanol‐containing liquid diet resulted in the development of ONFH with hepatic steatosis, hepatic dysfunction and hyperlipidaemia, whereas feeding the dextran‐containing diet did not cause ONFH. However, we could not recognize any relationship between the pro‐inflammatory response via TLR4 and the development of alcohol‐induced ONFH. Thus in this study we have developed a new rat model for alcohol‐induced ONFH based on the feeding of an ethanol liquid diet. ONFH was observed within seven days from the start of feeding with 5% ethanol‐containing liquid diet. Although this was linked to hepatic steatosis, a TLR4 association was not a feature of this model.

Assessment of SMAD4, p53, and Ki-67 alterations as a predictor of liver metastasis in human colorectal cancer

PurposeThe liver is the most common site of metastasis in patients with colorectal cancer (CRC), and this is a determinant of the prognosis. However, no reliable molecular predictors of liver metastasis have yet been identified.MethodsSixty-two surgical specimens of colorectal cancer were studied. The first group included 25 patients who achieved a disease-free survival period of at least 6 years (CRC-M0), and the second group included 37 patients with synchronous (n = 22) or metachronous (n = 15) liver metastasis (CRC-M1). SMAD4, p53, and Ki-67 expression levels were assessed immunohistochemically.ResultsThe loss of SMAD4 expression and elevated Ki-67 expression were found significantly more frequently in CRC-M1 patients than in CRC-M0 patients (P = 0.0047 and P = 0.013, respectively). Statistically significant differences were also observed between the CRC-M0 group and the metachronous metastasis group. No difference was seen in the overexpression of p53 between the groups. A combination analysis of SMAD4 and Ki-67 revealed no cases with maintained levels of SMAD4 and a low Ki-67 expression had or developed liver metastasis.ConclusionThe loss of SMAD4 expression and elevated Ki-67 expression was therefore found to significantly correlate with liver metastasis, regardless of the time of occurrence, thus indicating these factors to be predictive markers for liver metastasis in patients with CRC.

Sentinel lymph node biopsy after neoadjuvant chemotherapy predicts pathological axillary lymph node status in breast cancer patients with clinically positive axillary lymph nodes at presentation

BackgroundIt is still controversial whether axillary lymph node (ALN) dissection (ALND) can be omitted after negative sentinel lymph node (SLN) biopsy (SLNB) in breast cancer (BC) patients with clinically positive ALNs at presentation treated with neoadjuvant chemotherapy (NAC). The study aim was to analyze whether SLNB could be useful in these patients.MethodsIn a retrospective study, eligible patients were women with invasive BC with clinically positive ALNs at presentation, treated with NAC then a total or partial mastectomy, with an intraoperative histological examination of SLNs and non-SLNs suspicious for metastasis followed by ALND. Non-SLNs suspicious for metastasis were defined as hard or large nodes located in the same level of the axilla where clinically positive ALNs had been initially identified. The results of SLNB and clinicopathological characteristics were analyzed for correlation with pathological ALN status.ResultsIn a consecutive series of 105 women with 107 BC cases, 81 (75.7xa0%) had at least 1 SLN, and the remaining 26 (24.3xa0%) had at least 1 non-SLN suspicious for metastasis. The intraoperative (or final) histological examination of these nodes revealed that the false-negative (FN) rate and accuracy were 8.2 (or 6.3)xa0% and 95.1 (or 96.3)xa0%, respectively. Estrogen receptor status at presentation, pathological tumor response, lymphovascular invasion after NAC, and NAC regimen were correlated with pathological ALN status.ConclusionThe histological examination of SLNs and that of non-SLNs suspicious for metastasis are useful for predicting pathological ALN status in BC patients with clinically positive ALNs at presentation who are treated with NAC.