An investigation was retrospectively made regarding the lateral lymph node dissection in 96 cases of lower rectal cancer excised at the Tokyo Medical University Hospital between 1989 and 1998. Lateral lymph node dissection was performed in cases of invasion to the proper tunica muscularis recti or deeper and in cases of metastasis to the lymph nodes surrounding the rectum or beyond (that is, metastasis to lymph nodes farther than the rectum periphery). Lateral lymph node metastasis was recognized in 8 of 31 cases (25.8%) making up the dissection group, and in these cases, upward lymph node metastasis was at n1 or above and invasion was a1 or beyond. Local recurrence was found in 12 of 31 cases (38.7%) with lateral lymph node dissection and in 12 of 65 cases (18.6%) with no lateral lymph node dissection (control group). In a comparison with the control group by the Kaplan-Meier method, the disease-free survival rate was significantly lower in the dissection group. In a multivariate analysis by Cox's proportional hazard model, lymph node metastasis (p=0.022) was found to correlate with prognosis, but no significant correlation with lateral lymph node dissection was manifested.

In order to evaluate the influence of Th1-related cytokines on disease progression, the levels of interleukin-12 (IL-12), interferon-gamma (INF-γ) and tumor necrosis factor-alpha (TNF-α), helper T cell (Th) subsets, and natural killer (NK) cells were examined in 337 Japanese patients with histologically confirmed primary adenocarcinomas of the stomach and colorectal and in 172 control subjects.Levels of IL-12, IFN-γ, TNF-α, and Th1 cells were significantly lower in cancer patients than those in the control group. On the other hand, levels of Th2 cells and NK cells were significantly higher in cancer patients than those in the control group. Th1-related cytokines were suppressed even in early-stage patients. Results of the present study suggest that Th1-related immune parameters were suppressed in cancer patients, even in early-stage patients, and that they were useful as immunological markers for detecting groups of patients at high risk for cancer.

Using a hand-held gene gun, we examined the effects of murine interleukin-12 IL-12) gene transfection on metastatic tumors. AH 130 cells at high (1×107) and low (1 ×106) doses were inoculated into the liver of Donryu rats through the portal vein. On the twelfth day following tumor inoculation, the hepatic surface was bombarded with IL-12 cDNA (4μg)-coated gold particles emitted by pressurized helium gas (300 psi). The corresponding amount of β-galactosidase (β-gal) cDNA was injected as a control in the same manner. The high-dose model was highly fatal and used for estimation of the survival rate. The low-dose model was investigated to evaluate alterations in the number of tumors, histological findings, and cytokine expression in the liver and spleen. Nontumor-bearing rats were employed for study of any adverse effects gene gun shots induce on body weight, peripheral blood cell counts, and liver function.The IL-12 gene therapy was effective in terms of the 60-day survival rate (IL-12 50% vs. control 15%, p<0.05). Seven days after DNA transfer the average number of metastatic tumors in the liver increased in the control group, while it diminished in the gene therapy group. Histological examination revealed that most tumor cells in the control group were viable, whereas some of those in the IL-12 group underwent necrotic changes accompanied by massive lymphocytic infiltration. IL-12 and IFN-γ were expressed in the liver and spleen in greater amounts in the IL-12 group than in the control. No remarkable adverse effects were expressed in non-tumor-bearing rats undergoing gene bombazdment either with β-gal or IL-12 genes. Thus, this procedure may be applied clinically as a promising therapeutic option for metastatic tumor of the liver. A hand-held gene gun seems especially useful for transfection during laparotomy due to its ability to accurately and instantaneously inject exogenous genes under direct vision.

Estrogen receptor alpha (ERα) variant proteins lacking the hormone-binding domains translated from their splice variant mRNAs were examined by Western blot analysis of 80 cases of human breast cancer. Wild ERα protein (ERwtP) was expressed in 68 cases (85.0%), and of these cases, 40 (58.8%) co-expressed ERα variant protein corresponding in size to 41kDa (ERd5P). There was a significant correlation between co-expression of ERd5P and the splice variant mRNA lacking exon 5 (ERd5M) examined by reverse transcription-polymerase chain reaction. No protein bands for ERα variant corresponding in size to 52kDa (ERd7P) were observed in spite of the splice variant mRNA lacking exon 7 (ERd7M) being co-expressed with wild-type mRNA. Our results suggest that ERd5P persists and is stable in a large proportion of samples of human breast cancer tissue, whereas ERd7P is not. The functional difference between ERwtP and ERd5P has yet to be established, and its discovery may demonstrate the importance of ERd5P for anti-estrogen resistance in human breast cancer.

We evaluated the pharmacokinetics of anticancer drugs, drug concentration in tissues of the liver and the pancreas, and the hematological changes in aortic stop-flow infusion with hypoxic abdominal perfusion (ASI with HAP) using Beagle dogs under general anesthesia.Concerning the of blood concentrations of both mitomycin C (MMC) and 5-fluorouracil (5-FU), the area under the curve (AUC) with perfusion circuit (PC) in the ASI with HAP group was significantly higher than in the control group. On the contrary, there was no significant difference for AUC in the non-PC as compared with that in the control group. From these results, this method is effective to increase the blood concentration of drugs in target organs. It is suggested that the maximum dose of anticancer drugs in ASI with HAP should not greatly exceed the dose given in systemic administration by rapid intravenous injection.Drug concentrations of both MMC and 5-FU in the ASI with HAP group were significantly higher than those in the control group in the liver and in the pancreas. Concentrations of MMC and 5-FU in hepatic tissue were lower than those in pancreatic tissue, and there was a tendency for the concentration in hepatic tissue to decline more rapidly in comparison of pancreatic tissue. This is ascribed to the fact that the catabolism of both agents occurs mainly in the liver.The measurements of blood gas indicated that a hypoxic condition was maintained only in PC, and PC became lower in pH during perfusion. The results of blood biochemical examinations revealed that the variations in each parameter peaked between 15 and 30 minutes after completion of perfusion and that they all reached a plateau 60 minutes after completion. The increases of hepatic enzymes such as AST, ALT and LDH were ascribed to ischemia due to the aorta stop-flow and to the reperfusion injury of the liver following release of stop-flow. Superoxide dismutase (SOD) exhibited a sharp increase immediately after administration of anticancer drugs, which was ascribed to the influence of MMC administration. However, these biochemical changes in ASI with HAP were believed to be reversible and of short duration.

Using a hand-held gene gun which accelerates DNA-coated microparticles, we examined the effect of interleukin-12 (IL-12) and/or tumor necrosis factor-α (TNF-α) gene transfection a rat solid tumor model. Yoshida sarcoma cells were inoculated subcutaneously into the chests of Donryu rats. Then 4μg of IL-12 and/or TNF-α DNA-coated gold (Au) particles was injected into the tumor by pressurized helium (He) gas at 400psi (1psi=6, 890Pa) on day 5 and 7 after tumor inoculation. The corresponding dose of β-galactosidase was given as a control. Compared with the control, injection of TNF-α, IL-12, and IL-12 plus TNF-α effectively inhibited tumor growth and improved the survival rate. TNF-α alone prolonged the survival of tumor-bearing rats, but the animals still died within 41 days after tumor injection, On the other hand, IL-12 alone and IL-12 plus TNF-α completely cured 20% and 40% of the rats, respectively. IL-12 plus TNF-α gene therapy using the gene gun showed a synergetic effect on the survival of tumor-bearing rats. This procedure might useful for the clinical treatment of solid cancer. In particular, there is a possibility of intraoperative gene transfection because the gene gun can introduce multiple genes very rapidly.

Cancer is often a systemic disease and cancer cells can be disseminated during surgery, so we have to keep in mind the possibility of residual tumor cells even after curative resection. Cancer surgery also induces high levels of various proinflammatory cytokines and their induction is proportional to the extent of surgery. Cytokines stimulate the growth, invasion, and metastasis of cancer cells, either directly or via the induction of adhesion molecules and angiogenesis factors.Therefore, we have to avoid dissemination of cancer cells during surgery and perform less invasive surgery to avoid excessive cytokine release. When cancer is diagnosed as a systemic disease, postoperative adjuvant chemotherapy is needed. Recent advances in molecular biology have made it easy to determine the presence or absence of cancer cells in blood, lymph nodes, and bone marrow. These methods can also be used to avoid unnecessary adjuvant chemotherapy, reducing the risk of side effects.

To determine whether preoperative levels of carcinoembryonic antigen (CEA) and acute-phase reactants (APR), such as immunosuppressive acidic protein (IAP), α 1-antichymotrypsin (ACT), acid-soluble glycoproteins (ASP), and sialic acid, before immunotherapy using protein-bound polysaccharide K (PSK) can predict the clinical outcome in patients with gastric cancer. Seven hundred and twelve patients were enrolled in the study from February 1987 to November 1989 at 16 institutions throughout Japan. All patients were followed over a period of 5 years. Among the 712 patients, 694 (97.5%) eligible patients with biopsy-proven gastric adenocarcinoma underwent gastrectomy and were randomly assigned to receive supportive therapy as follows: gastrectomy alone, gastrectomy plus PSK, gastrectomy plus chemotherapy (CT), and gastrectomy+CT+PSK. The 5-year follow up rate was 94.5%. There was a significant difference in survival between patients receiving gastrectomy with or without PSK who showed abnormal serum levels of CEA (log-rank test, P=0.0175), and both CEA and APR (log-rank test, P=0.0431), and between those receiving PSK and not receiving PSK in those with parameter point 3 (log-rank test, P=0.0404). These results indicate that PSK therapy has a beneficial effect in gastric cancer patients with high levels of CEA and APR.

Small cell lung carcinoma (SCLC) is a common and frequently fatal malignancy for which there is no satisfactory treatment. The amphibian peptide bombesin and its mammalian counterpart, gastrinreleasing peptide, act as autocrine growth factors for SCLC cells. Vasoactive intestinal peptide (VIP) inhibited the growth and multiplication of a SCLC cell line, NCl-H345. VIP-induced suppression of cell proliferation was enhanced by an anti-bombesin monoclonal antibody. Isobutylmethyl xanthine (IBMX) and forskolin, which elevate intracellular cyclic (c) AMP levels, enhanced VIP-stimulated cAMP production. IBMX and forskolin inhibited cell growth and enhanced VIP-induced suppression of cell proliferation. The inhibition by VIP and other cAMP-promoting agents paralleled their ability to stimulate cellular production of cyclic adenosine monophosphate. The anti-mitogenic activity of VIP and its enhancement by anti-bombesin antibody and other cAMP-promoting agents provide a potential new approach to the treatment of SCLC.

The relationship between apoptosis and p53 protein expression in squamous cell carcinoma of the esophagus was investigated immunohistochemically in 47 biopsy specimens from 24 patients. Sixteen of the specimens were well differentiated, 11 were moderately differentiated, and 20 were poorly differentiated. The TUNEL method was used for detecting apoptosis. TUNEL-positive condensed nuclei showing characteristic morphological features were considered to indicate apoptosis. p53 protein expression was studied immunohistochemically. One thousand tumor cells were evaluated in each specimen. The incidence of apoptosis was less than 1% except in one specimen. More than 50% of the tumor cells were p53-positive in 33 specimens, while less than 10% of the tumor cells were positive in 14 specimens. There was no significant difference in the incidence of apoptosis or in the mean percentage of p53-positive cells between the 3 histological subtypes. There was also no significant correlation between the incidence of apoptosis and the extent of p53 protein expression.